Σφακιανάκης Αλέξανδρος
ΩτοΡινοΛαρυγγολόγος
Αναπαύσεως 5 Άγιος Νικόλαος
Κρήτη 72100
00302841026182
00306932607174
alsfakia@gmail.com

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Τετάρτη 25 Απριλίου 2018

A Clinical Study of Effect of Hyperpyrexia on Otoacoustic Emissions in Children

Abstract

Various degrees of sensory neural hearing loss can be seen in the progression of some hereditary periodic fever syndromes. Otoacoustic emission testing can help to establish the inner ear involvement at an early period of a periodic fever with a risk of hearing loss (Abdul Kadir et al. in J Int Adv Otol 9(2.79):08–11, 2014). Sensorineural hearing loss is the common most complication of bacterial meningitis in childhood (Richardson in Pediatrics 102(6):1364–1368, 1998). When present from birth, or acquired in the pre-school years, hearing loss of any degree, even mild hearing loss, interferes with speech and language development. In addition to obvious communication deficits, the consequences of hearing loss in children and adults include psychosocial problems, such as frustration, irritability, anxiety, the tendency to withdraw from social interactions, and even depression (Dhar and Hall in Otoacoustic emissions: principles, procedures, and protocols, Plural Publishing, San Diego, 2011). OAE are acoustic signals emitted from cochlea to the middle ear and into the external ear where they are recorded. Evoked OAE are undetectable when deafness is above 30–35 dB Sound pressure level (Biswas in Clinical audio-vestibulometry for otologists and neurologists, Bhalani Publishing House, Mumbai, 1995). OAEs permit early detection of inner ear abnormalities associated with a wide variety of diseases and disorders, including Alport syndrome etc. With early detection, the serious consequences of hearing loss can sometimes be prevented. With proper identification and diagnosis of hearing impairment, timely and effective management for the same can be taken. Data for this study was collected from children (5–14 years) attending the Department of Otorhinolaryngology and Paediatrics Out-patient departments in P.E.S.I.M.S.R, Kuppam. Among the study population 43 (57.3%) were male and 32 (42.7%) were females showing the slight male preponderance. study was done on children with temperature > 1000 F, children with temperature were screened with OAE, and OAE was recorded in same children once fever has subsided and results were compared. This is a new study where we compared same group of children with fever and once fever has subsided. In most other studies, study group was compared to the healthy control group. In our study, children with fever having abnormal FDP values at f1were 9, they reverted back to base line once fever has subsided. This shows that there is no much damage to inner ear at lower frequencies. Almost 47 abnormal FDP values at f2 reverted back to normal. At higher frequencies (f3 and f4), there is no much change in abnormal FDPs with fever and after fever has subsided, this shows that there is more damage to inner ear at higher frequencies. This study demonstrated that hyperpyrexia causes hearing loss in children with fever probably due to cochlear involvement. We conclude that OAE can be used as a screening tool in detecting hearing loss among children because the technique is simple, reproducible, not expensive, not time consuming also effectively narrows down the children with high chances of hearing loss thereby effectively improves the chances of early diagnosis and hence children can be rehabilitated early, making a marked change in their future.



https://ift.tt/2I1X01J

Novel compound heterozygous variants in the XPC gene identified in a Chinese xeroderma pigmentosum group C patient with ovarian teratoma

The Journal of Dermatology, EarlyView.


https://ift.tt/2Kgmysv

Sweet's syndrome with laryngoparalysis due to laryngitis

The Journal of Dermatology, EarlyView.


https://ift.tt/2Jrq5D7

Interleukin‐33 is expressed in the lesional epidermis in herpes virus infection but not in verruca vulgaris

The Journal of Dermatology, EarlyView.


https://ift.tt/2KgVlX1

Mild dystrophic epidermolysis bullosa associated with homozygous gene mutation c.6216+5G>T in type VII collagen ultrastructurally suggestive of the decreased number of anchoring fibrils

The Journal of Dermatology, EarlyView.


https://ift.tt/2Jrq3et

A Video-Based Coaching Intervention to Improve Surgical Skill in Fourth-Year Medical Students

Publication date: Available online 24 April 2018
Source:Journal of Surgical Education
Author(s): Mitchell B. Alameddine, Michael J. Englesbe, Seth A. Waits
ObjectiveFor senior medical students pursuing careers in surgery, specific technical feedback is critical for developing foundational skills in preparation for residency. This pilot study seeks to assess the feasibility of a video-based coaching intervention to improve the suturing skills of fourth-year medical students.DesignFourth-year medical students pursuing careers in surgery were randomized to intervention vs. control groups and completed 2 video recorded suture tasks. Students in the intervention group received a structured coaching session between consecutive suturing tasks, whereas students in the control group did not. Each coaching session consisted of a video review of the students' first suture task with a faculty member that provided directed feedback regarding technique. Following each suturing task, students were asked to self-assess their performance and provide feedback regarding the utility of the coaching session. All videos were deidentified and graded by independent faculty members for evaluation of suture technique.SettingThe University of Michigan Medical School in Ann Arbor, Michigan.ParticipantsAll fourth-year medical students pursuing careers in surgical specialties were contacted via e-mail for voluntary participation. In all, 16 students completed both baseline and follow up suture tasks.ResultsAll students who completed the coaching session would definitely recommend the session for other students. A total of 94% of the students strongly agreed that the exercise was a beneficial experience, and 75% strongly agreed that it improved their technical skills. Based on faculty grading, students in the intervention group demonstrated greater average improvements in bimanual dexterity compared to students in the control group; whereas students in the control group demonstrated greater average improvements in domains of efficiency and tissue handling compared to the intervention group. Based on student self-assessments, those in the intervention group had greater subjective improvements in all scored domains of bimanual dexterity, efficiency, tissue handling, and consistency compared to the control group. Subjective, free-response comments centered on themes of becoming more aware of hand movements when viewing their suturing from a new perspective, and the usefulness of the coaching advice.ConclusionsThis pilot study demonstrates the feasibility of a video-based coaching intervention for senior medical students. Students who participated in the coaching arm of the intervention noticed improvements in all domains of technical skill and noted that the experience was overwhelmingly positive. In summary, video-based review shows promise as an educational tool in medical education as a means to provide specific technical feedback.



https://ift.tt/2JuFZg9

Is There an Influence of Surgeon’s Experience on the Clinical Course in Patients With a Proximal Femoral Fracture?

Publication date: Available online 24 April 2018
Source:Journal of Surgical Education
Author(s): Claudio Canal, Alexander Kaserer, Bernhard Ciritsis, Hans-Peter Simmen, Valentin Neuhaus, Hans-Christoph Pape
ObjectivesTeaching of surgical procedures is of paramount importance. However, it can affect patients outcome. The aim of this study was to evaluate if teaching of hip fracture surgery is an independent predictor for negative in-hospital outcome.Design and SettingRetrospectively, we analyzed all hip fracture patients between 2008 and 2013 recorded in a national quality measurement database (AQC). Inclusion criteria were proximal femoral fracture (ICD-10 diagnostic codes S72.00-S72.11), surgical care of those fracture and a documented teaching status of the intervention. Variables were sought in bivariate and multivariate analyses. Teaching status was entered in multiple regression analysis models for in-hospital death, complications and length of stay while controlling for confounders.ParticipantsIn the 6-year study period, a total of 4397 patients at a mean age of 80 years met the inclusion criteria. Totally, 48% (n = 2107) of the procedures were conducted as teaching interventions. The rest of our examined cases (n = 2290) were conducted as nonteaching procedures.ResultsThere was no association between teaching and mortality, but complications (odds ratio = 1.3; 95% CI: 1.04–1.5; p = 0.018) and prolonged hospitalization (standardized beta = 0.045, p = 0.002) were more likely to occur in the teaching group while controlling for confounders.ConclusionsThere appears to be no effect of the educational status on the in-hospital death in patients with a proximal femoral fracture. However, teaching was an independent predictor of complications and longer length of stay. Although the differences were significant, the clinical outcome was comparable in both groups, thus justifying the benefits of resident teaching.



https://ift.tt/2Ki9wem

Understanding Surgical Resident and Fellow Perspectives on Their Operative Performance Feedback Needs: A Qualitative Study

Publication date: Available online 22 April 2018
Source:Journal of Surgical Education
Author(s): Ricardo J. Bello, Samuel Sarmiento, Meredith L. Meyer, Gedge D. Rosson, Damon S. Cooney, Scott D. Lifchez, Carisa M. Cooney
ObjectiveOperative performance feedback is essential for surgical training. We aimed to understand surgical trainees′ views on their operative performance feedback needs and to characterize feedback to elucidate factors affecting its value from the resident perspective.DesignUsing a qualitative research approach, 2 research fellows conducted semistructured, one-on-one interviews with surgical trainees. We analyzed recurring themes generated during interviews related to feedback characteristics, as well as the extent to which performance rating tools can help meet trainees′ operative feedback needs.SettingDepartments or divisions of general or plastic surgery at 9 US academic institutions.ParticipantsSurgical residents and clinical fellows in general or plastic surgery.ResultsWe conducted 30 interviews with 9 junior residents, 14 senior residents, and 7 clinical fellows. Eighteen (60%) participants were in plastic and 12 (40%) were in general surgery. Twenty-four participants (80%) reported feedback as very or extremely important during surgical training. All trainees stated that verbal, face-to-face feedback is the most valuable, especially if occurring during (92%) or immediately after (65%) cases. Of those trainees using performance rating tools (74%), most (57%) expressed positive views about them but wanted the tools to complement and not replace verbal feedback in surgical education. Trainees value feedback more if received within 1 week or the case.ConclusionsVerbal, face-to-face feedback is very or extremely important to surgical trainees. Residents and fellows prefer to receive feedback during or immediately after a case and continue to value feedback if received within 1 week of the event. Performance rating tools can be useful for providing formative feedback and documentation but should not replace verbal, face-to-face feedback. Considering trainee views on feedback may help reduce perceived gaps in feedback demand-versus-supply in surgical training, which may be essential to overcoming current challenges in surgical education.



https://ift.tt/2FiuEx3

Validation of a Low-Cost Do-It-Yourself Model for Neonatal Thoracoscopic Congenital Diaphragmatic Hernia Repair

Publication date: Available online 20 April 2018
Source:Journal of Surgical Education
Author(s): Pedro Reino-Pires, Manuel Lopez
ObjectiveWe aimed to develop and validate a low cost, do-it-yourself model for neonatal thoracoscopic congenital diaphragmatic hernia (CDH).DesignVolunteers with varying skills in neonatal minimally invasive surgery tested and evaluated the model simulating a neonatal thoracoscopic CDH repair. The model was built from ordinary materials purchased in a dime store: a small food container, a neoprene band simulating a diaphragm, an inflated balloon simulating a spleen, a tissue chord simulating intestine, and a body wash sponge simulating a collapsed lung. The evaluation comprised 3 sets of 5-point grading scale concerning appearance, necessary maneuvers, and ability to generate skills. Bowel reduction and suture efficacy was verified for each test.SettingMinimally invasive surgery simulation room at Pediatric Surgery Department of Hospital Universitario de Vall d'Hebron, Barcelona, Spain.ParticipantsVolunteer residents and specialists of pediatric surgery.ResultsBowel reduction was possible in every test, with 1 spleen rupture, 1 bowel entrapment, and 2 inappropriate sutures due to tension. Most volunteers considered the general endoscopic vision (63.2%), external and internal dimensions (both 89.5%) to be highly similar; bowel reduction (68.4%) and diaphragm's manipulation and suture (57.9%) to be highly or very highly similar. Regarding its ability to generate skills, most considered it to be very or extremely useful concerning: camera handling (52.6%), working in small spaces and suture (both 100%), and tissue handling (63.2%). The least liked features were the colors and the diaphragm's tension. The size, portability, and the reproducibility were the most liked features.ConclusionsWe consider this low cost and easily reproducible model to be realistic enough for CDH repair training, having the potential to be adapted for other simulations.



https://ift.tt/2KhYK7A

Mentorship in Orthopedics: A National Survey of Orthopedic Surgery Residents

Publication date: Available online 25 April 2018
Source:Journal of Surgical Education
Author(s): Lasun O. Oladeji, Brent A. Ponce, John R. Worley, James A. Keeney
ObjectiveMentorship is an important component of graduate medical education. It has been associated with numerous benefits including personal development, increased career satisfaction, and reduced stress and burnout. The purpose of this study was to assess orthopedic resident attitudes regarding mentorship and to determine if there were sociodemographic differences.DesignA total of 243 orthopedic surgery residents completed this 25-item mixed response questionnaire.ResultsNearly two-thirds of residents conveyed that their training program either had a formal or informal mentorship program, and 95.8% of residents indicated that they believed mentorship played an important role with respect to their development as an orthopedic resident. Minorities were more likely to have a mentor that was obtained while they were in medical school, less likely to have multiple mentors, and more likely to be dissatisfied with the quality of mentorship in residency. Females were more likely to pursue a mentor on their own. Overall, 31% of orthopedic residents were classified as experiencing burnout. There was no difference in the prevalence of mentorship in respondents experiencing burnout, but they were more likely to be unsatisfied with the quality of mentorship in residency. Finally, only two-thirds of residency programs have mentorship programs despite the fact that the vast majority of orthopedic residents believe that the mentorship plays an important role in their development as surgeons.ResultsGiven these findings, future work should focus on identifying and addressing race and sex-based mentorship disparities while simultaneously working to improve access to mentorship for all residents.



https://ift.tt/2Fibesg

Feasibility and Benefit of Incorporating a Multimedia Cadaver Laboratory Training Program into a Didactics Curriculum for Junior and Senior Surgical Residents

Publication date: Available online 18 April 2018
Source:Journal of Surgical Education
Author(s): Erika Simmerman, Andrew Simmerman, Randi Lassiter, Ray King, Ben Ham, Bao-Ling Adam, Colville Ferdinand, Steven Holsten
ObjectiveAs operative experience in general surgery decreases and work hour limitations increase there is less exposure of surgical residents to advanced vascular and trauma exposures. Many institutions have demonstrated benefits of cadaver laboratory courses. We have incorporated a multimedia cadaver laboratory course into our general surgery residency didactics curriculum with the objective to demonstrate a benefit of the program as well as the feasibility of incorporation.Study DesignThis is a prospective study at a tertiary care institution including general surgery residents within our residency program. A curriculum was designed, requiring residents to complete multimedia learning modules before both a trauma cadaver laboratory and vascular exposure cadaver laboratory. Outcome measures included self-efficacy/confidence (precourse and postcourse 5-point Likert surveys), knowledge (net performance on precourse and postcourse multiple choice examinations), and resident perception of the curriculum (postcourse 5-point Likert survey). Data were analyzed using ANOVA paired t-tests.ResultsFor the vascular cadaver laboratory, resident knowledge improved overall from an average of 41.2% to 50.0% of questions correct (p = 0.032) and self-efficacy/confidence improved by 0.59 from 1.52 to 2.11 out of 5 (p = 0.009). Median confidence is 1.37 out of 5 and 2.32 out of 5, before and after course, respectively. Wilcoxon nonparametric test reveals a p = 0.011. Resident's perception of the usefulness of the laboratory evaluation was 3.85 out 5. There were 85.71% agreed that the laboratory is useful and 14.29% were disagree. The Z-score is −0.1579 (means 0.1579 standard deviations a score of 3.85 below the benchmark). The percentile rank is 56.27%. The coefficient of variation is 24.68%.For the trauma cadaver laboratory, resident knowledge improved overall from an average of 55.89% to 66.17% of questions correct (p = 0.001) and self-efficacy/confidence improved by 0.75 from 1.68 out of 5 to 2.43 out of 5 (p = 0.011). Median confidence level is 1.41 out of 5 before the training course and 2.64 out of 5 after the training course. Wilcoxon signed rank test gives a p value of 0.008. Resident's perception of the usefulness of the laboratory evaluation was 3.94 out 5. There were 72.22% agreed that the laboratory is useful and 27.78% were neutral. The Z-score is −0.098 (means 0.098 standard deviations a score of 3.94 below the benchmark). The percentile rank is 53.90%. The coefficient of variation is 15.48%.ConclusionsIncorporating a multimedia cadaver laboratory into a residency education didactics curriculum was both feasible and beneficial for resident education. We demonstrate an improvement in knowledge and self efficacy/confidence following both cadaver laboratory courses.



https://ift.tt/2Ki9xPs

The Effects of Feedback Fatigue and Sex Disparities in Medical Student Feedback Assessed Using a Minute Feedback System

Publication date: Available online 17 April 2018
Source:Journal of Surgical Education
Author(s): Meredith Barrett, Patrick Georgoff, Niki Matusko, Lisa Leininger, Rishindra M. Reddy, Gurjit Sandhu, David T. Hughes
ObjectiveFeedback is critical to the development of medical students. To enhance feedback, we created a web application, the Minute Feedback System (MFS). This app allows students to request precise, timely, written feedback from residents and staff without the burden of vague, end-of-rotation surveys. In this study, we investigate variations in response rates and feedback fatigue based on sex and rank (resident/fellow vs. faculty).DesignData were collected from May 2015-October 2016. The MFS stores student requests for feedback along with faculty responses allowing for analysis of feedback response rate as well as sex and rank identification. Variation in response rate was analyzed using Chi-square and log-rank testing. Feedback fatigue was assessed using Cox regression modeling.SettingUniversity Affiliated, Tertiary Care Center.ParticipantsMedical Students, Residents and Faculty.ResultsAbout 98.6% of students (138 women, 140 men) used the MFS on their surgery clerkship. They requested feedback from 159 trainees (residents or fellows) and 114 surgical faculty. Feedback was requested more from faculty (26.3 requests per individual) compared to trainees (16.4 requests per individual).The overall evaluator response rate was 60%. Male students were 13% less likely to receive feedback than female students. There was a higher prevalence of feedback fatigue among female faculty (11% less likely to respond) and residents (23% less likely to respond). Regression analysis showed that the overall hazard of nonresponse over time was 1.05, indicative of overall feedback fatigue among all respondents.ConclusionsThe MFS is a novel tool for feedback used by nearly all M3 students during their surgery clerkship at our institution. Evaluation of response rates demonstrated feedback fatigue, especially among women faculty and residents. Feedback fatigue was more likely to affect male students, although the reason for this is unclear. Further analysis is necessary to understand this sex-associated response disparity and its effect on student feedback in the learning environment.



https://ift.tt/2JqY7re

Mixed-Method Evaluation of a Cadaver Dissection Course for General Surgery Interns: An Innovative Approach for Filling the Gap Between Gross Anatomy and the Operating Room

Publication date: Available online 16 April 2018
Source:Journal of Surgical Education
Author(s): Yen-Yi Juo, Christina Hanna, Quach Chi, Grace Chang, Warwick J. Peacock, Areti Tillou, Catherine E. Lewis
ObjectiveTo evaluate an innovative whole cadaver dissection curriculum designed to focus on teaching procedure-relevant anatomy and surgical skills to surgery interns.DesignA mixed methods explanatory sequential design incorporating both quantitative and qualitative evaluations was used to evaluate the cadaver dissection course. Quantitative data were prospectively collected and retrospectively reviewed in order to compare anatomy knowledge and operative skills before and after the course. In the qualitative phase, open-ended telephone interviews were conducted in order to explore the major strengths and weaknesses of the course and gain a more in-depth understanding of resident perceptions and attitudes toward the course.SettingAll UCLA categorical surgery interns who have undergone the cadaver dissection curriculum between the years 2010 to 2016 were recruited for evaluation and interview.ParticipantsFrom 2010 to 2016, 6 to 7 categorical surgery interns were enrolled in the cadaver dissection course each year.ResultsAnatomy practical examination scores increased following implementation of the course from 50.5% to 83.5% (p < 0.01). Faculty ratings of operative skills improved as well (average Likert scale rating for technical skills improved from 4.1 ± 0.4 to 4.4 ± 0.3, p = 0.06). Almost all interviewees (96%) reported that the course improved their knowledge of anatomy, and 78% of respondents believed the course was conducive to improving technical skills.ConclusionsWe believe that cadaver dissection courses offer a superior educational model for teaching clinically relevant anatomy as well as surgical skills. We found improvements in anatomy knowledge and technical skills, and trainees expressed strongly favorable views of the program.



https://ift.tt/2KgTbqn

The Economics of Private Practice versus Academia in Surgery

Publication date: Available online 16 April 2018
Source:Journal of Surgical Education
Author(s): Maria Baimas-George, Brian Fleischer, James R. Korndorffer, Douglas Slakey, Christopher DuCoin
ObjectiveResidents often make career decisions regarding future practice without adequate knowledge to the realities of professional life. Currently there is a paucity of data regarding economic differences between practice models. This study seeks to illuminate the financial differences of surgical subspecialties between academic and private practice.DesignData were collected from the Association of American Medical College (AAMC) and the Medical Group Management Association's (MGMA) 2015 reports of average annual salaries. Salaries were analyzed for general surgery and 7 subspecialties. Fixed time of practice was set at 30 years. Assumptions included 5 years as assistant professor, 10 years as associate professor, and 15 years as full professor. Formula used: (average yearly salary) × [years of practice (30 yrs − fellowship/research yrs)] + ($50,000 × yrs of fellowship/research) = total adjusted lifetime revenue.ResultsAs a full professor, academic surgeons in all subspecialties make significantly less than their private practice counterparts. The largest discrepancy is in vascular and cardiothoracic surgery, with full professors earning 16% and 14% less than private practitioners. Plastic surgery and general surgery are the only 2 disciplines that have similar lifetime revenues to private practitioners, earning 2% and 6% less than their counterparts′ lifetime revenue.ConclusionsAcademic surgeons in all surgical subspecialties examined earn less lifetime revenue compared to those in private practice. This difference in earnings decreases but remains substantial as an academic surgeon advances. With limited exposure to the diversity of professional arenas, residents must be aware of this discrepancy.



https://ift.tt/2FlaFOE

Resident-Specific Morbidity Reduced Following ACS NSQIP Data-Driven Quality Program

Publication date: Available online 16 April 2018
Source:Journal of Surgical Education
Author(s): Florence E. Turrentine, John B. Hanks, Megan C. Tracci, R. Scott Jones, Bruce D. Schirmer, Philip W. Smith
BackgroundThe Accreditation Council for Graduate Medical Education Milestone Project for general surgery provided a more robust method for developing and tracking residents' competence. This framework enhanced systematic and progressive development of residents' competencies in surgical quality improvement.Study DesignA 22-month interactive, educational program based on resident-specific surgical outcomes data culminated in a quality improvement project for postgraduate year 4 surgery residents. Self- assessment, quality knowledge test, and resident-specific American College of Surgeons National Surgical Quality Improvement Program Quality In-Training Initiative morbidity were compared before and after the intervention.ResultsQuality in-training initiative morbidity decreased from 25% (82/325) to 18% (93/517), p = 0.015 despite residents performing more complex cases. All participants achieved level 4 competency (4/4) within the general surgery milestones improvement of care, practice-based learning and improvement competency. Institutional American College of Surgeons National Surgical Quality Improvement Program general surgery morbidity improved from the ninth to the sixth decile. Quality assessment and improvement self-assessment postintervention scores (M = 23.80, SD = 4.97) were not significantly higher than preintervention scores (M = 19.20, SD = 5.26), p = 0.061. Quality Improvement Knowledge Application Tool postintervention test scores (M = 17.4, SD = 4.88), were not significantly higher than pretest scores (M = 13.2, SD = 1.92), p = 0.12.ConclusionSharing validated resident-specific clinical data with participants was associated with improved surgical outcomes. Participating fourth year surgical residents achieved the highest score, a level 4, in the practice based learning and improvement competency of the improvement of care practice domain and observed significantly reduced surgical morbidity for cases in which they participated.



https://ift.tt/2Ke4PC8

Treatment choice, satisfaction and quality of life in patients with Graves’ disease

Clinical Endocrinology, EarlyView.


https://ift.tt/2r0StW1

Effects of the two types of anorexia nervosa (binge eating/purging and restrictive) on bone metabolism in female patients

Clinical Endocrinology, EarlyView.


https://ift.tt/2Hvxvoz

Frontal sinus schwannoma

Publication date: Available online 25 April 2018
Source:European Annals of Otorhinolaryngology, Head and Neck Diseases
Author(s): J. Petersen, L. Gilain, A. Coutu, N. Saroul
IntroductionNasal sinus schwannomas are rare tumors, particularly in the frontal sinus.Case reportThe authors report the case of a woman with left frontal sinus schwannoma discovered in a context of frontal sinusitis with orbital and ocular complications. The surgical procedure consisted of endonasal tumor resection and external drainage.DiscussionThe pathogenesis of frontal sinus schwannomas remains unclear. These tumors can present with a wide range of clinical and radiological signs, making them difficult to diagnosis. Surgical resection of these tumors is also complex.



https://ift.tt/2HtFE0E

A review of the mechanisms of action of dimethylfumarate in the treatment of psoriasis

Experimental Dermatology, EarlyView.


https://ift.tt/2FhqKEY

A Clinical Study of Effect of Hyperpyrexia on Otoacoustic Emissions in Children

Abstract

Various degrees of sensory neural hearing loss can be seen in the progression of some hereditary periodic fever syndromes. Otoacoustic emission testing can help to establish the inner ear involvement at an early period of a periodic fever with a risk of hearing loss (Abdul Kadir et al. in J Int Adv Otol 9(2.79):08–11, 2014). Sensorineural hearing loss is the common most complication of bacterial meningitis in childhood (Richardson in Pediatrics 102(6):1364–1368, 1998). When present from birth, or acquired in the pre-school years, hearing loss of any degree, even mild hearing loss, interferes with speech and language development. In addition to obvious communication deficits, the consequences of hearing loss in children and adults include psychosocial problems, such as frustration, irritability, anxiety, the tendency to withdraw from social interactions, and even depression (Dhar and Hall in Otoacoustic emissions: principles, procedures, and protocols, Plural Publishing, San Diego, 2011). OAE are acoustic signals emitted from cochlea to the middle ear and into the external ear where they are recorded. Evoked OAE are undetectable when deafness is above 30–35 dB Sound pressure level (Biswas in Clinical audio-vestibulometry for otologists and neurologists, Bhalani Publishing House, Mumbai, 1995). OAEs permit early detection of inner ear abnormalities associated with a wide variety of diseases and disorders, including Alport syndrome etc. With early detection, the serious consequences of hearing loss can sometimes be prevented. With proper identification and diagnosis of hearing impairment, timely and effective management for the same can be taken. Data for this study was collected from children (5–14 years) attending the Department of Otorhinolaryngology and Paediatrics Out-patient departments in P.E.S.I.M.S.R, Kuppam. Among the study population 43 (57.3%) were male and 32 (42.7%) were females showing the slight male preponderance. study was done on children with temperature > 1000 F, children with temperature were screened with OAE, and OAE was recorded in same children once fever has subsided and results were compared. This is a new study where we compared same group of children with fever and once fever has subsided. In most other studies, study group was compared to the healthy control group. In our study, children with fever having abnormal FDP values at f1were 9, they reverted back to base line once fever has subsided. This shows that there is no much damage to inner ear at lower frequencies. Almost 47 abnormal FDP values at f2 reverted back to normal. At higher frequencies (f3 and f4), there is no much change in abnormal FDPs with fever and after fever has subsided, this shows that there is more damage to inner ear at higher frequencies. This study demonstrated that hyperpyrexia causes hearing loss in children with fever probably due to cochlear involvement. We conclude that OAE can be used as a screening tool in detecting hearing loss among children because the technique is simple, reproducible, not expensive, not time consuming also effectively narrows down the children with high chances of hearing loss thereby effectively improves the chances of early diagnosis and hence children can be rehabilitated early, making a marked change in their future.



https://ift.tt/2I1X01J

Unexpected Response Profiles Seen in Hepatitis C Virus-Infected Patients Treated with Sofosbuvir Plus Ribavirin: Five Case Reports

Viral Immunology, Ahead of Print.


https://ift.tt/2Hxsyvr

Target-enriched sequencing of chromosome 17q21.31 in sporadic tauopathies reveals no candidate variants

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Publication date: June 2018
Source:Neurobiology of Aging, Volume 66
Author(s): Cristina Razquin, Sara Ortega-Cubero, Estefania Rojo-Bustamante, Monica Diez-Fairen, Elena Lorenzo, Elena Alonso, Mario Ezquerra, Owen A. Ross, Maria Carcel, Oswaldo Lorenzo-Betancor, Alexandra I. Soto, Jeremy D. Burgess, Nilüfer Ertekin-Taner, Dennis W. Dickson, Maria A. Pastor, Eduard Tolosa, Pau Pastor
The main genetic risk factors for progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD) are located at chromosome 17q21.31. The identification of risk H1 subhaplotypes suggests that disease-specific variants can be identified by resequencing the 17q21.31 region (1.4 Mb) in carriers of risk H1 subhaplotypes. We hypothesized that PSP/CBD H1 subhaplotype carriers could have undergone a mutational event absent among unaffected carriers leading to the disease risk. We performed this strategy in definite PSP subjects, definite CBD subjects, and healthy controls and tried to replicate the findings in a larger PSP/CBD case-control series. In the resequencing process, 40 candidate variants were identified, but an association between PSP and rs76970862 was replicated only using an unadjusted model. Gene expression association analysis of this variant suggested no potential functional effect. Although our results failed to identify disease-associated variants, it is still possible that the risk of PSP/CBD at chromosome 17 is driven by rare variants, even in PSP/CBD H1 cases or variants located outside the capture regions.



https://ift.tt/2HsNUhD

Cerebrospinal fluid β-amyloid42 and neurofilament light relate to white matter hyperintensities

Publication date: August 2018
Source:Neurobiology of Aging, Volume 68
Author(s): Katie E. Osborn, Dandan Liu, Lauren R. Samuels, Elizabeth E. Moore, Francis E. Cambronero, Lealani Mae Y. Acosta, Susan P. Bell, Michelle A. Babicz, Elizabeth A. Gordon, Kimberly R. Pechman, L. Taylor Davis, Katherine A. Gifford, Timothy J. Hohman, Kaj Blennow, Henrik Zetterberg, Angela L. Jefferson
White matter hyperintensities (WMHs) are associated with poorer brain health, but their pathophysiological substrates remain elusive. To better understand the mechanistic underpinnings of WMHs among older adults, this study examined in vivo cerebrospinal fluid biomarkers of β-amyloid42 deposition (Aβ42), hyperphosphorylated tau pathology, neurodegeneration (total tau), and axonal injury (neurofilament light [NFL]) in relation to log-transformed WMHs volume. Participants free of clinical stroke and dementia were drawn from the Vanderbilt Memory & Aging Project (n = 148, 72 ± 6 years). Linear regression models adjusted for age, sex, race/ethnicity, education, intracranial volume, modified Framingham Stroke Risk Profile (excluding points assigned for age), cognitive diagnosis, and APOE-ε4 carrier status. Aβ42 (β = −0.001, p = 0.007) and NFL (β = 0.0003, p = 0.01) concentrations related to WMHs but neither hyperphosphorylated tau nor total tau associations with WMHs reached statistical significance (p-values > 0.21). In a combined model, NFL accounted for 3.2% of unique variance in WMHs and Aβ42 accounted for an additional 4.3% beyond NFL, providing novel evidence of the co-occurrence of at least 2 distinct pathways for WMHs among older adults, including amyloid deposition and axonal injury.



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Cover 2: Editorial Advisory Board

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Publication date: June 2018
Source:Neurobiology of Aging, Volume 66





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The association of mid-to late-life systemic inflammation with white matter structure in older adults: The Atherosclerosis Risk in Communities Study

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Publication date: August 2018
Source:Neurobiology of Aging, Volume 68
Author(s): Keenan A. Walker, B. Gwen Windham, Melinda C. Power, Ron C. Hoogeveen, Aaron R. Folsom, Christie M. Ballantyne, David S. Knopman, Elizabeth Selvin, Clifford R. Jack, Rebecca F. Gottesman
We examined whether the pattern of middle- to late-life systemic inflammation was associated with white matter (WM) structural abnormalities in older adults. A total of 1532 participants (age = 76.5; standard deviations = 5.4) underwent 3T brain magnetic resonance imaging to quantify white matter hyperintensity volume and whole-brain WM microstructural integrity (fractional anisotropy, mean diffusivity). High-sensitivity C-reactive protein (CRP), a marker of systemic inflammation, was measured at 3 visits (21 and 14 years before, and concurrent with, neuroimaging). Participants were categorized into 1 of 6 groups based on their 21-year pattern of low (<3 mg/L) versus elevated (≥3 mg/L) CRP. Compared to the group with low CRP at all 3 visits, the group that transitioned from low to elevated CRP during midlife demonstrated greatest white matter hyperintensity volume and poorest WM microstructural integrity, after adjusting for demographic variables and cardiovascular risk factors. Participants with high CRP at all visits also demonstrated greater WM structural abnormalities, but only after accounting for differential attrition. These results suggest that increasing and persistent inflammation in the decades spanning middle-to late-life may promote WM disease in older adults.



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Preferential consolidation of emotionally salient information during a nap is preserved in middle age

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Publication date: August 2018
Source:Neurobiology of Aging, Volume 68
Author(s): Sara E. Alger, Elizabeth A. Kensinger, Jessica D. Payne
Sleep preferentially preserves aspects of memory that are most salient and valuable to remember at the expense of memory for less relevant details. Daytime naps and nocturnal sleep enhance this emotional memory trade-off effect, with memory for emotional components correlated with slow-wave sleep during the day and rapid eye movement sleep overnight. However, these studies have primarily sampled from young adult populations. Sleep and memory are altered by middle age, and the aim of the present study was to examine how age affects sleep-based mechanisms of emotional memory prioritization, using a daytime nap protocol to compare young to middle-aged adults. In both age groups, a nap soon after encoding scenes that contained a negative or neutral object on a neutral background led to superior retention of emotional object memory at the expense of memory for the related backgrounds. Sleep spindle activity during slow-wave sleep was related to memory for this emotionally salient information across the age range.



https://ift.tt/2HtuTvu

Shades of white: diffusion properties of T1- and FLAIR-defined white matter signal abnormalities differ in stages from cognitively normal to dementia

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Publication date: August 2018
Source:Neurobiology of Aging, Volume 68
Author(s): Joost M. Riphagen, Ed HBM. Gronenschild, David H. Salat, Whitney M. Freeze, Dimo Ivanov, Lies Clerx, Frans R.J. Verhey, Pauline Aalten, Heidi I.L. Jacobs
The underlying pathology of white matter signal abnormalities (WMSAs) is heterogeneous and may vary dependent on the magnetic resonance imaging contrast used to define them. We investigated differences in white matter diffusivity as an indicator for white matter integrity underlying WMSA based on T1-weighted and fluid-attenuated inversion recovery (FLAIR) imaging contrast. In addition, we investigated which white matter region of interest (ROI) could predict clinical diagnosis best using diffusion metrics. One hundred three older individuals with varying cognitive impairment levels were included and underwent neuroimaging. Diffusion metrics were extracted from WMSA areas based on T1 and FLAIR contrast and from their overlapping areas, the border surrounding the WMSA and the normal-appearing white matter (NAWM). Regional diffusivity differences were calculated with linear mixed effects models. Multinomial logistic regression determined which ROI diffusion values classified individuals best into clinically defined diagnostic groups. T1-based WMSA showed lower white matter integrity compared to FLAIR WMSA-defined regions. Diffusion values of NAWM predicted diagnostic group best compared to other ROI's. To conclude, T1- or FLAIR-defined WMSA provides distinct information on the underlying white matter integrity associated with cognitive decline. Importantly, not the "diseased" but the NAWM is a potentially sensitive indicator for cognitive brain health status.



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The effect of rare variants in TREM2 and PLD3 on longitudinal cognitive function in the Wisconsin Registry for Alzheimer's Prevention

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Publication date: June 2018
Source:Neurobiology of Aging, Volume 66
Author(s): Corinne D. Engelman, Burcu F. Darst, Murat Bilgel, Eva Vasiljevic, Rebecca L. Koscik, Bruno M. Jedynak, Sterling C. Johnson
Recent studies have found an association between functional variants in TREM2 and PLD3 and Alzheimer's disease (AD), but their effect on cognitive function is unknown. We examined the effect of these variants on cognitive function in 1449 participants from the Wisconsin Registry for Alzheimer's Prevention, a longitudinal study of initially asymptomatic adults, aged 36–73 years at baseline, enriched for a parental history of AD. A comprehensive cognitive test battery was performed at up to 5 visits. A factor analysis resulted in 6 cognitive factors that were standardized into z scores (∼N [0, 1]); the mean of these z scores was also calculated. In linear mixed models adjusted for age, gender, practice effects, and self-reported race/ethnicity, PLD3 V232M carriers had significantly lower mean z scores (p = 0.02) and lower z scores for story recall (p = 0.04), visual learning and memory (p = 0.049), and speed and flexibility (p = 0.02) than noncarriers. TREM2 R47H carriers had marginally lower z scores for speed and flexibility (p = 0.06). In conclusion, a functional variant in PLD3 was associated with significantly lower cognitive function in individuals carrying the variant than in noncarriers.



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Individual Differences in Working Memory Capacity and Filtering.

Author: Robison, Matthew K.; Miller, Ashley L.; Unsworth, Nash
DOI: 10.1037/xhp0000513
Publication Date: POST AUTHOR CORRECTIONS, 23 April 2018


https://ift.tt/2HRyId7

Redundancy Gain in the Simon Task: Does Increasing Relevant Activation Reduce the Effect of Irrelevant Activation?.

Author: Mittelstadt, Victor; Miller, Jeff
DOI: 10.1037/xhp0000523
Publication Date: POST AUTHOR CORRECTIONS, 23 April 2018


https://ift.tt/2FhetQV

Long-Term and Short-Term Action-Effect Links and Their Impact on Effect Monitoring.

Author: Wirth, Robert; Steinhauser, Robert; Janczyk, Markus; Steinhauser, Marco; Kunde, Wilfried
DOI: 10.1037/xhp0000524
Publication Date: POST AUTHOR CORRECTIONS, 23 April 2018


https://ift.tt/2I1REn9

Is There Lexical Competition in the Recognition of L2 Words for Different-Script Bilinguals? An Examination Using Masked Priming With Japanese-English Bilinguals.

Author: Nakayama, Mariko; Lupker, Stephen J.
DOI: 10.1037/xhp0000525
Publication Date: POST AUTHOR CORRECTIONS, 23 April 2018


https://ift.tt/2FhHQm6

A facile synthesis and assembly of ultrasmall Pt nanoparticles on reduced graphene oxide‑carbon black hybrid for enhanced performance in PEMFC

Publication date: 5 August 2018
Source:Materials & Design, Volume 151
Author(s): Melike Sevim Yılmaz, Begüm Yarar Kaplan, Önder Metin, Selmiye Alkan Gürsel
A new and straightforward approach for the synthesis of ultrasmall and monodisperse Pt nanoparticles (NPs) and their controlled assembly on graphene based supports including reduced graphene oxide (rGO), commercial carbon black (VC) and rGO-VC hybrid were reported. These supported NPs were utilized as the electrocatalysts for polymer electrolyte membrane fuel cells (PEMFC). Surfactant-assisted reduction of platinum(II) acetylacetonate in hot organic solution yielded 1.2 nm Pt NPs. These ultrasmall Pt NPs were decorated on rGO, VC and the rGO-VC hybrid by using a simple liquid-phase self-assembly method. In the previous studies on Pt/rGO-VC hybrids, on one hand, Pt NPs were synthesized in situ on support, on the other hand, VC was added to synthesized Pt/rGO, and their fuel cell performance have been rarely shown. In our study, rGO and VC were directly mixed and prepared Pt NPs were assembled on rGO-VC hybrid support. Pt/rGO-VC hybrid electrocatalyst possessed substantially better electrocatalytic activity owing to better utilization of Pt compared to Pt/rGO and Pt/VC. Membrane electrode assemblies based on resultant catalysts were characterized in-situ in PEMFC. A superior PEMFC performance of 857 mW cm−2 (maximum power density) was achieved with the hybrid catalyst as compared to Pt NPs supported on rGO or VC.

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Bipolar resistive switching and memristive properties of hydrothermally synthesized TiO2 nanorod array: Effect of growth temperature

Publication date: 5 August 2018
Source:Materials & Design, Volume 151
Author(s): A.C. Khot, N.D. Desai, K.V. Khot, M.M. Salunkhe, M.A. Chougule, T.M. Bhave, R.K. Kamat, K.P. Musselman, T.D. Dongale
In the present work, the hydrothermal approach is employed to develop 1D-TiO2 nanorod array memristive devices and the effect of hydrothermal growth temperature on TiO2 memristive devices is studied. X-ray diffraction (XRD) analysis suggested that the rutile phase is dominant in the developed TiO2 nanorod array. Field emission scanning electron microscopy (FESEM) images show well adherent and pinhole free one dimensional (1D) TiO2 nanorods. The presence of titanium and oxygen in all the samples was confirmed by energy dispersive X-ray spectroscopy (EDS). Furthermore, growth of the 1D TiO2 nanorods depends on the growth temperature and uniform growth is observed at the higher growth temperatures. The well-known memristive hysteresis loop is observed in the TiO2 nanorod thin films. Furthermore, resistive switching voltages, the shape of I-V loops and (non)rectifying behavior changed as the growth temperature varied from 140 °C to 170 °C. The biological synapse properties such as paired-pulse facilitation and short-term depression are observed in some devices. The detailed electrical characterizations suggested that the developed devices show doubled valued charge-magnetic flux characteristic and charge transportation is due to the Ohmic and space charge limited current.

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Uranyl fluorescence lifetime in nanoporous silica gel: The influence of pore size, pH, and water

Publication date: 5 August 2018
Source:Materials & Design, Volume 151
Author(s): Brandon M. Dodd, Gary C. Tepper
The fluorescence lifetime of uranyl adsorbed within nanoporous silica gel was measured as a function of pore size at two different pH values and both wet and dry. It was determined that for uranyl adsorbed within pores larger than 4 nm, the lifetime is relatively independent of pore size, whereas below 4 nm, the lifetime increases with decreasing pore size. A blue shift in the emission spectra was observed at the smallest pore size (2.2 nm) and is believed to be caused by quantum confinement. The lifetime was found to be longer at a neutral pH than in an acidic pH, and this is caused by the formation of a uranyl hydroxyl complex at higher pH values. The presence of water within the pores is found to increase the fluorescence lifetime at all pore sizes and pH values studied in this paper; this is caused by the formation of a uranyl silicate bond in the absence of water. An understanding of the parameters that influence the fluorescence lifetime of uranyl within silica gel is important for the development of more sensitive detection methods.

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In-situ growth of highly monodisperse ITO nanoparticles regulated by mesoporous silica glasses

Publication date: 5 August 2018
Source:Materials & Design, Volume 151
Author(s): Ping Chen, Zhangru Chen, Shaodong Hou, Xiang Shen, Yingbo Chu, Yu Yang, Luyun Yang, Jinyan Li, Nengli Dai
In this work, we firstly introduce a facile method to synthesize bulk silica glass contained indium tin oxide nanoparticles (ITO NPs). Water solution with InCl3 and SnCl4 was mixed and dipped into the mesoporous silica glass (MSG) followed by an in-situ growth of ITO NPs under 1000 °C heat treatment. X-ray diffraction (XRD) and transmission electron microscopy (TEM) show that the ITO NPs are highly monodisperse and crystalline in the silica glass with size around 20–30 nm. The size and distribution of ITO NPs can be regulated by the mesopores of mesoporous silica glass (MSG) effectively. The absorption and photoluminescence (PL) spectra exhibit an optical band gap and a PL emission of the ITO NPs doped silica glass at 3.12 eV and 560 nm, respectively. Results indicate that this kind of composite material has potential applications for optical nonlinearity, plasmonic formation, and sensing in the future.

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Editorial Board

Publication date: 5 July 2018
Source:Materials & Design, Volume 149





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Optimal microstructural design for high thermal stability of pure FCC metals based on studying effect of twin boundaries character and network of grain boundaries

Publication date: 5 August 2018
Source:Materials & Design, Volume 151
Author(s): Hossein Alimadadi, Alice Bastos Fanta, Ryutaro Akiyoshi, Takeshi Kasama, Anthony D. Rollett, Marcel A.J. Somers, Karen Pantleon

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https://ift.tt/2HOE494

Vapor-defect-solid growth mechanism for NanoNets utilizing natural defect networks in polycrystals

Publication date: 15 July 2018
Source:Materials & Design, Volume 150
Author(s): Zumin Wang, Eric J. Mittemeijer
Nanowires are major building components for nanotechnology. The growth and the assembly of nanowires are often complicated and expensive, which has impeded practical applications of such nanotechnology. This work discloses a Vapor-Defect-Solid (VDS) mechanism for growth of nanowall networks (NanoNets), by exploring a spontaneous interaction of vapor and defect networks in polycrystalline materials. A kinetic model analysis of the precondition and the characteristics of the VDS growth process is presented. The VDS growth mechanism allows straightforward, fast growth of two-dimensional NanoNets at near room temperature from vapor sources with a very high production yield, and thus holds potential as a general route for large-area production of NanoNets at a reduced cost. The VDS growth mechanism further allows exploration of fundamental knowledge of grain-boundary networks in nanocrystalline materials, and opens new avenues for grain-boundary engineering.

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Simple method for estimating cutaneous neurofibromas in patients with neurofibromatosis 1

The Journal of Dermatology, Volume 45, Issue 5, Page 626-627, May 2018.


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Erythema induratum of Bazin: Epidemiological, clinical and laboratorial profile of 54 patients

The Journal of Dermatology, Volume 45, Issue 5, Page 628-629, May 2018.


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Heterogeneous nanostructure array for electrochemical energy conversion and storage

Publication date: Available online 25 April 2018
Source:Nano Today
Author(s): Min Zhou, Yang Xu, Yong Lei
Rapid development of modern society raises more and more requirements for highly efficient energy conversion and storage. Electrochemical devices stand out as a most viable option for eventual substitute for fossil fuels, but suffer from problems like durability, operability, etc. Heterogeneous nanostructure arrays with distinguished superiorities have thus attracted intensive attention and yielded favorable electrochemical performance. In pursuit of deep understandings of their working modes, this review will focus on the interconnection among different constituents within each individual unit to correlate microscopic electrochemical processes with macroscopic performance. Here, the motivation of employing heterogeneous nanostructure arrays is first summarized. Then, the design principles, including three working modes, 'Function-Function', 'Function-Assistance', 'Single-unit device', are analyzed comprehensively to illuminate the interconnection among different constituents in electrochemical energy conversion and storage processes. Solar water splitting (energy conversion), alkali-ion battery and supercapacitors (energy storage) are termed collectively as typical electrochemical energy technologies to illustrate the superiorities of heterogeneous nanostructure arrays. Finally, perspectives of related fields will be concluded to broaden the future of heterogeneous nanostructure arrays.

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Inventory of methane emissions from livestock in China from 1980 to 2013

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Publication date: July 2018
Source:Atmospheric Environment, Volume 184
Author(s): Jiashuo Yu, Shushi Peng, Jinfeng Chang, Philippe Ciais, Patrice Dumas, Xin Lin, Shilong Piao
Livestock is the largest anthropogenic methane (CH4) source at the global scale. Previous inventories of this source for China were based on the accounting of livestock populations and constant emission factors (EFs) per head. Here, we re-evaluate how livestock CH4 emissions have changed from China over the last three decades, considering increasing population, body weight and milk production per head which cause EF to change with time, and decreasing average life span (ALS) of livestock. Our results show that annual CH4 emissions by livestock have increased from 4.5 to 11.8 Tg CH4 yr−1 over the period 1980–2013. The increasing trend in emissions (0.25 Tg CH4 yr−2) over this period is ∼12% larger than that if using constant EFs and ALS. The increasing livestock population, production per head and decreasing ALS contributed +91%, +28% and −19% to the increase in CH4 emissions from livestock, respectively. This implies that the temporal changes in EF and ALS of livestock cannot be overlooked in inventories, especially in countries like China where livestock production systems are experiencing rapid transformations.



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Homologous series of n-alkanes (C19-C35), fatty acids (C12-C32) and n-alcohols (C8-C30) in atmospheric aerosols from central Alaska: Molecular distributions, seasonality and source indices

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Publication date: July 2018
Source:Atmospheric Environment, Volume 184
Author(s): Suresh K.R. Boreddy, Md. Mozammel Haque, Kimitaka Kawamura, Pingqing Fu, Yongwon Kim
To better understand the molecular distributions, seasonality and source indices of organic aerosols in central Alaska, we measured homologous series of n-alkanes (C19-C35), fatty acids (C12-C32) and n-alcohols (C8-C30) in total suspended aerosols collected during June 2008 to 2009 using a gas chromatography/mass spectrometry (GC-MS). The whole sampling period was divided as warm (early May to late September; summer) and cold (late September to early May; winter) periods. Molecular distribution was characterized in both periods by the predominance of C25 for n-alkanes and C24:0 for fatty acids. However, we noticed a difference in molecular distribution of n-alcohols between warm and cold periods, which was characterized by the predominance of C22 in warm season while C26 in cold period. Except for fatty acids, n-alkanes and n-alcohols showed higher concentrations in warm period than in cold period. We found significantly higher ratios of C18:1/C18:0 in warm period than those in cold period, suggesting the fresh biogenic and aged anthropogenic aerosols in warm and cold periods, respectively. This inference was consistent with significantly higher ratios of WSOC/OC, a proxy for photochemical aging, in cold period. Based on the carbon preference index (CPI), average chain length (ACL), low-to-high molecular weight (LMW/HMW) ratios, wax n-alkanes (%WNA) and estimated fossil fuel concentrations, we demonstrate that higher plant waxes, biomass burning from wildfires are two important sources in warm period while combustion derived anthropogenic emissions are major sources in cold period in central Alaska. This finding was further supported by higher ratios of nss-K+/elemental carbon (EC) and methanesulfonate (MSA)/EC ratios in warm period.



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A cool-temperate young larch plantation as a net methane source - A 4-year continuous hyperbolic relaxed eddy accumulation and chamber measurements

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Publication date: July 2018
Source:Atmospheric Environment, Volume 184
Author(s): Masahito Ueyama, Kota Yoshikawa, Kentaro Takagi
Upland forests are thought to be methane (CH4) sinks due to oxidation by methanotrophs in aerobic soils. However, CH4 budget for upland forests are not well quantified at the ecosystem scale, when possible CH4 sources, such as small wet areas, exists in the ecosystem. Here, we quantified CH4 fluxes in a cool-temperate larch plantation based on four-year continuous measurements using the hyperbolic relaxed eddy accumulation (HREA) method and dynamic closed chambers with a laser-based analyzer. After filling data gaps for half-hourly data using machine-learning-based regressions, we found that the forest acted as a net CH4 source at the canopy scale: 30 ± 11 mg CH4 m−2 yr−1 in 2014, 56 ± 8 mg CH4 m−2 yr−1 in 2015, 154 ± 5 mg CH4 m−2 yr−1 in 2016, and 132 ± 6 mg CH4 m−2 yr−1 in 2017. Hotspot emissions from the edge of the pond could strongly contribute to the canopy-scale emissions. The magnitude of the hotspot emissions was 10–100 times greater than the order of the canopy-scale and chamber-based CH4 fluxes at the dry soils. The high temperatures with wet conditions stimulated the hotspot emissions, and thus induced canopy-scale CH4 emissions in the summer. Understanding and modeling the dynamics of hotspot emissions are important for quantifying CH4 budgets of upland forests. Micrometeorological measurements at various forests are required for revisiting CH4 budget of upland forests.



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Real world vehicle fleet emission factors: Seasonal and diurnal variations in traffic related air pollutants

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Publication date: July 2018
Source:Atmospheric Environment, Volume 184
Author(s): Jonathan M. Wang, Cheol-Heon Jeong, Naomi Zimmerman, Robert M. Healy, Greg J. Evans
Temporal variations of vehicle emissions are affected by various compounding factors in the real world. The focus of this study is to determine the effects of ambient conditions and post-tailpipe changes on traffic emissions measured in the near-road region. Emission factors allowed for the isolation of the traffic signal and accounted for effects of local meteorology and dilution. Five month-long measurement campaigns were conducted at an urban near-road site that exhibited a broad range of ambient conditions with temperatures ranging between −18 and +30 °C. Particle number emission factors were 2.0× higher in the winter relative to the summer, which was attributed to changes in particles post-tailpipe. Conversely, toluene emissions were 2.5× higher in the summer relative to the winter, attributed to changes in fuel composition. Diurnal trends of emission factors showed substantial increases in emissions during the morning rush hour for black carbon (1.9×), particle number (2.4×), and particle-bound polycyclic aromatic hydrocarbons (3.0×), affected by fleet make-up. In contrast, particle number emission factors were highest midday with mean values 3.7× higher than at night. This midday increase was attributed to particle formation or growth from local traffic emissions and showed different wind direction dependence than regional events.



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Small-scale variations in ozone concentration in low mountains

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Publication date: July 2018
Source:Atmospheric Environment, Volume 184
Author(s): Isao Kanda, Shinji Wakamatsu
In a relatively low mountain area adjacent to Matsuyama city in Japan, ozone concentration variations were studied at spatial scales of O(10)∼O(103) m. Walking mobile measurements were complemented by vertical profiling, wind measurements, and passive sampling. The broad-scale distribution at O(102)∼O(103) m was found to depend on time of day, atmospheric stability, and geography in ways consistent with previous studies. Well-defined areas of low ozone concentrations O(10) m in width were found at several locations. No distinctive features of these locations were immediately discernible, but detailed examination of the temporal variations coupled with the wind field suggested that the distribution of the low-ozone areas was determined by subtle differences in the terrain topography.



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Composite Faces are not (Necessarily) Processed Coactively: A Test Using Systems Factorial Technology and Logical-Rule Models.

Author: Cheng, Xue Jun; McCarthy, Callum J.; Wang, Tony S. L.; Palmeri, Thomas J.; Little, Daniel R.
DOI: 10.1037/xlm0000479
Publication Date: POST AUTHOR CORRECTIONS, 23 April 2018


https://ift.tt/2r12sdg

Associations or Repetitions? Testing the Basis of the Perruchet Effect in Voluntary Response Speed.

Author: Lee Cheong Lem, V. Annabelle; Moul, Caroline; Harris, Justin A.; Livesey, Evan J.
DOI: 10.1037/xlm0000556
Publication Date: POST AUTHOR CORRECTIONS, 23 April 2018


https://ift.tt/2HvDc9V

Allograph Priming Is Based on Abstract Letter Identities: Evidence From Japanese Kana.

Author: Kinoshita, Sachiko; Schubert, Teresa; Verdonschot, Rinus G.
DOI: 10.1037/xlm0000563
Publication Date: POST AUTHOR CORRECTIONS, 23 April 2018


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A Further Examination of Word Frequency and Age-of-Acquisition Effects in English Lexical Decision Task Performance: The Role of Frequency Trajectory.

Author: Juhasz, Barbara J.; Yap, Melvin J.; Raoul, Akila; Kaye, Micaela
DOI: 10.1037/xlm0000564
Publication Date: POST AUTHOR CORRECTIONS, 23 April 2018


https://ift.tt/2r5KmqD

The Motor Locus of No-Go Backward Crosstalk.

Author: Durst, Moritz; Janczyk, Markus
DOI: 10.1037/xlm0000565
Publication Date: POST AUTHOR CORRECTIONS, 23 April 2018


https://ift.tt/2HsTmAO

The Resilience of Verbal Sequence Learning: Evidence From the Hebb Repetition Effect.

Author: St-Louis, Marie-Eve; Hughes, Robert W.; Saint-Aubin, Jean; Tremblay, Sebastien
DOI: 10.1037/xlm0000566
Publication Date: POST AUTHOR CORRECTIONS, 23 April 2018


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Traffic-emitted metal status and uptake by Carex meyeriana Kunth and Thelypteris palustris var . pubescens Fernald growing in roadside turfy swamp in the Changbai Mountain area, China

Abstract

Six traffic-emitted metals (Cr, Zn, Cu, Cd, Pb, and Ni) were determined in soil and plants for below- and aboveground parts along different distances from highway to evaluate their behavior and uptake by Carex meyeriana Kunth and Thelypteris palustris var. pubescens Fernald growing in turfy swamps. The results indicated that the different plant tissues showed significantly different levels of metal content. Nonlinear regression analysis indicated that metal contents leveled off at constant values before they decreased as the distance from the roadside increased. The high R2 values of the regression model indicated good fit of the exponential function applied to depict the distribution pattern of the metal elements. It was deduced that Cr, Cu, and Cd in Thelypteris palustris var. pubescens Fernald were mainly derived from the soil; Carex meyeriana Kunth and Thelypteris palustris var. pubescens Fernald absorbed Pb mainly through the stomata from atmospheric depositions; Cr, Cu, and Cd in Carex meyeriana Kunth and Zn in Thelypteris palustris var. pubescens Fernald were mainly affected by soil and atmospheric depositions. After excluding the effects of traffic, only the bioaccumulation factor of Cd (1.34) in Carex meyeriana Kunth and the translocation factor of Zn (1.13) in Thelypteris palustris var. pubescens Fernald were greater than 1, suggesting that Carex meyeriana Kunth could be a good candidate for assimilating Cd from soils and Thelypteris palustris var. pubescens Fernald could be suitable for the phytoextraction of Zn.



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[The role of adventitia in hypoxic vascular remodeling].

Related Articles

[The role of adventitia in hypoxic vascular remodeling].

Sheng Li Xue Bao. 2018 Apr 25;70(2):211-216

Authors: Yu FY, Yang SC, Ji ES

Abstract
As an important site for the production, storage and release of key regulators for vascular function, the vascular adventitia is thought to be a damage sensing tissue in the vascular wall under certain conditions. The adventitial cells are usually the first ones to respond to vascular stress or injury, and consequently affect the structure and function of blood vessel wall. Growing lines of evidence have shown that the vascular adventitia exhibits the earliest and most prominent changes in vascular remodeling due to hypoxia and related pulmonary hypertension and atherosclerosis. In particular, fibroblasts play an important role in the adaptation and regulation to local microenvironmental changes. This review focuses on the role of vascular adventitia in hypoxia-induced vascular remodeling and the underlying molecular mechanisms.

PMID: 29691586 [PubMed - in process]



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[Neurobiological mechanisms of autistic savant and acquired savant].

Related Articles

[Neurobiological mechanisms of autistic savant and acquired savant].

Sheng Li Xue Bao. 2018 Apr 25;70(2):201-210

Authors: Zhang Y, Han VZ

Abstract
The autism spectrum is a pervasive developmental disorder characterized by profound social and verbal communication deficits, stereotypical motor behaviors, restricted interests, and cognitive abnormalities. It affects approximately 1% of children in most of the reported nations and regions. One of the most fascinating and mysterious features of autism, however, is the remarkable talent frequently found in people affected by it, namely autistic savant. A parallel and equally mysterious phenomenon is that some otherwise normal and ordinary individuals develop similarly remarkable talent after brain injuries, a disorder known as acquired savant. After decades of intensive investigation, significant progress has been made in these fields. Current studies indicate that autistic savant and acquired savant are neuropathologically related, and these disorders share many neurobiological mechanisms. This review summarizes current knowledge of autism and both two savant types, and how it may aid our understanding of higher brain functionalities.

PMID: 29691585 [PubMed - in process]



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High level of Mn in brain is a risk for Alzheimer disease.

Related Articles

High level of Mn in brain is a risk for Alzheimer disease.

Sheng Li Xue Bao. 2018 Apr 25;70(2):193-200

Authors: Yu Q, Zhou YZ

Abstract
Alzheimer disease (AD) is a neurodegenerative disease. Manganese (Mn) is an essential trace element in the human body. It can enter the brain through the blood-brain barrier and blood-cerebrospinal fluid barrier. Excessive accumulation of Mn in the brain may disturb the homeostasis of the central nervous system (CNS) microenvironment and cause severe neuronal damage. The most recent data suggest that excessive Mn is associated with impaired learning and memory in animal models, and may lead to irreversible and progressive mild cognitive impairment and AD. However, the mechanism for the involvement of Mn in AD pathogenesis remains controversial. This paper reviews the effects of Mn on CNS, mitochondrial function, p53 expression, and amyloid precursor protein/β-amyloid metabolism, and analyzes the relationship between these effects and AD pathogenesis.

PMID: 29691584 [PubMed - in process]



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[ACE2 agonist DIZE alleviates lung injury induced by limb ischemia-reperfusion in mice].

Related Articles

[ACE2 agonist DIZE alleviates lung injury induced by limb ischemia-reperfusion in mice].

Sheng Li Xue Bao. 2018 Apr 25;70(2):175-183

Authors: Li SM, Wang XY, Liu F, Yang XH

Abstract
This study was aimed to explore the effect of angiotensin converting enzyme 2 (ACE2) agonist diminazene aceturate (DIZE) on acute lung injury (ALI) induced by limb ischemia-reperfusion (LIR) in mice. Male 8-week-old wild-type and hACE2 transgenic ICR mice were randomly divided into 6 groups (6 in each group), including wild-type control (W), wild-type model (WL), wild-type model with DIZE administration (WLD), transgenic control (T), transgenic model (TL), and transgenic model with DIZE administration (TLD) groups. LIR model was established by 4 h reperfusion following 2 h ischemia of bilateral hindlimbs with rubber bands in mice. The WLD and TLD groups were pretreated with DIZE (15 mg/kg, i.p.) for 4 weeks before LIR. At the end of LIR, the mice were sacrificed and lung tissues were sampled. Indexes for evaluating lung injury include organ coefficient and wet/dry weight ratio (W/D), cell count and protein concentration of bronchoalveolar lavage fluid (BALF), as well as morphological change and pathological score were detected. Angiotensin II (Ang II) and Ang (1-7) levels in lung tissue were determined by using ELISA commercial kits. And the protein expressions of angiotensin II type 1 receptor (AT1) and Mas receptor protein in lung tissue were detected by Western blot. The results were as follows: (1) There was obvious lung injury in both the WL and TL groups. The lung injury in the TL group was lighter than that in the WL group. DIZE could attenuate the lung injury in both the two groups. (2) The WL group showed increased Ang II and decreased Ang (1-7) levels, whereas the TL group did not exhibit any changes of these two proteins. DIZE decreased the level of Ang II in both the WL and TL groups, and increased the level of Ang (1-7) in the WL group. (3) In the WL and TL groups, AT1 and Mas receptor protein expressions were up-regulated. DIZE reversed the change of AT1 protein expression, whereas further increased Mas receptor expression in both the two groups. These results suggest that DIZE may improve the renin-angiotensin system homeostasis by regulating ACE2-Ang (1-7)-Mas axis in local lung tissue and play a protective role in LIR-induced ALI in mice.

PMID: 29691582 [PubMed - in process]



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[Upregulation of miR-498 suppresses Th17 cell differentiation by targeting STAT3 in rheumatoid arthritis patients].

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[Upregulation of miR-498 suppresses Th17 cell differentiation by targeting STAT3 in rheumatoid arthritis patients].

Sheng Li Xue Bao. 2018 Apr 25;70(2):167-174

Authors: Xiang HY, Pan F, Yan JZ, Hong LQ, Zhang LH, Liu YH, Feng X, Cai CS

Abstract
To investigate the effect and mechanism of miR-498 on Th17 cell differentiation of peripheral blood mononuclear cells (PMBCs) in rheumatoid arthritis (RA) patients, peripheral blood samples were collected from RA patients and healthy controls, respectively. The proportion of CD4+IL-17+ T cells (Th17 cells) or CD4+FOXP3+ T cells (Tregs) in T cells and the Th17/Treg ratio were identified by the flow cytometer. The STAT3 and miR-498 expression were measured by Western blot and real-time PCR, respectively. ELISA was used to detect IL-17 concentrations. Luciferase assay was performed to confirm that miR-498 directly targeted the 3' untranslated region (3'UTR) of STAT3 in CD4+ T cells. The effect of miR-498 on Th17 cell differentiation was explored by transfection of miR-498 mimic and/or pcDNA-STAT3 into CD4+ T cells. In PMBCs of RA patients, the Th17/CD4+ T cell ratio was significantly increased, while the Tregs/CD4+ T cell ratio was obviously decreased, leading to a higher Th17/Treg ratio. The results showed a reduced miR-498 expression and an increased STAT3 protein expression in PMBCs, and an increased IL-17 concentration in serum of RA patients. In cells transfected with wild-type-STAT3-LU, miR-498 mimic significantly reduced the luciferase activity, STAT3 gene and protein expression, and miR-498 inhibitor had an opposite function. While the miR-498 mimic/inhibitor had no effect on the luciferase activity and STAT3 expression in cells transfected with mutant-STAT3-LU. CD4+ T cells transfected with miR-498 mimic had a lower Th17/CD4+ T cell ratio and IL-17 concentration, however, transfection of pcDNA-STAT3 reversed the effect of miR-498 mimic on Th17/CD4+ T cell ratio and IL-17 concentration. These results suggest that overexpression of miR-498 suppresses Th17 cell differentiation by targeting STAT3 in RA patients.

PMID: 29691581 [PubMed - in process]



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[Angiotensin II promotes the expression of TXNIP through angiotensin II type 1 receptor in islet β cells].

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[Angiotensin II promotes the expression of TXNIP through angiotensin II type 1 receptor in islet β cells].

Sheng Li Xue Bao. 2018 Apr 25;70(2):149-157

Authors: Feng YJ, Wang J, Cao ZJ, Li D, Huo HY, Zhang XM, Jiao XY

Abstract
This study investigated the effect of angiotensin II (Ang II) on apoptosis and thioredoxin-interacting protein (TXNIP) expression in INS-1 islet cells and the underlying mechanism. INS-1 cells cultured in vitro were treated with different concentration of Ang II for different time, and the viability was measured using cell counting kit-8 (CCK-8). After treatment with 1 × 10-6 mol/L Ang II for 24 h, flow cytometry and Western blot were used to measure the cell apoptosis, and Western blot was used to analyze the protein expression of TXNIP, carbohydrate response element-binding protein (ChREBP) and angiotensin II type 1 receptor (AT1R). Real-time PCR was used to detect TXNIP and ChREBP mRNA expression. IF/ICC was used to observe the TXNIP, ChREBP and AT1R expression. The results showed that Ang II reduced cell viability and induced the expression of TXNIP in a dose- and time-dependent manner (P < 0.05, n = 6) compared with the control group. Ang II induced apoptosis and up-regulated the expression of ChREBP and AT1R (P < 0.05, n = 6). AT1R inhibitor, telmisartan (TM), blocked Ang II-induced TXNIP and ChREBP overexpression (P < 0.05, n = 6) and inhibited Ang II-induced apoptosis. Taken together, Ang II increased ChREBP activation through AT1R, which subsequently increased TXNIP expression and promoted cell apoptosis. These findings suggest a therapeutic potential of targeting TXNIP in preventing Ang II-induced INS-1 cell apoptosis in diabetes.

PMID: 29691579 [PubMed - in process]



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[Effects of thyroid hormone on macrophage dysfunction induced by oxidized low-density lipoprotein].

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[Effects of thyroid hormone on macrophage dysfunction induced by oxidized low-density lipoprotein].

Sheng Li Xue Bao. 2018 Apr 25;70(2):141-148

Authors: Ning Y, Zhang M, DU YH, Zhang HN, Li LY, Qin YW, Wen WW, Zhao QM

Abstract
It has been recognized that patients with hypothyroidism have higher risks of atherosclerosis and coronary heart disease, however, the mechanisms are largely unknown. Considering that macrophage dysfunction plays an important role in the formation and development of atherosclerosis plaques, this study aimed to investigate the direct effects of thyroid hormone on macrophage functions and to provide new insight for the mechanism of hypothyroid atherosclerosis. RAW264.7 cells (mouse leukaemic monocyte macrophage cell line) were incubated with oxidized low-density lipoprotein (oxLDL) to establish macrophage foam cells model in vitro, and the protective effects of different concentration of thyroxine (T4) on the macrophage foam cells function were explored. The proliferation, migration and cell aging of macrophages were detected by MTT method, scratch test and β-galactosidase staining respectively. The ELISA method was used to detect the secretion of tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), and interleukin-1β (IL-1β). Western blot analysis was applied to measure the phosphorylation of focal adhesion kinase (FAK), which was required for the process of proliferation and migration of macrophages. The results showed that oxLDL significantly inhibited the macrophage proliferation and migration, induced cell senescence, and promoted the secretion of TNF-α, MCP-1, and IL-1β; while T4 reversed those effects of oxLDL on macrophage in a concentration-dependent manner. Moreover, oxLDL increased the phosphorylation of FAK in macrophage, while T4 concentration-dependently reversed the effect. These results suggest that T4 modulates macrophage proliferation, migration, senescence, and secretion of inflammation factors in a concentration-dependent way.

PMID: 29691578 [PubMed - in process]



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[Ascending input from dorsal nuclei of lateral lemniscus mediates the plasticity of inferior colliculus neurons in mice].

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[Ascending input from dorsal nuclei of lateral lemniscus mediates the plasticity of inferior colliculus neurons in mice].

Sheng Li Xue Bao. 2018 Apr 25;70(2):132-140

Authors: Yang DD, Zheng WW, Zhao SS, Luo F, Wang X

Abstract
The auditory system has the ability to adjust its structure and function as the environment changes, which is called auditory plasticity. In the auditory system, inferior colliculus (IC) is an important relay station, which accepts the ascending inputs from dorsal nuclei of lateral lemniscus (DNLL). The present study was aimed to investigate the role of the DNLL in the formation of the plasticity of IC neurons. Here, we used extracellular single unit recording and electrical stimulation to investigate the plasticity of IC neurons in Kunming mice. The results showed that after the cessation of 30-minute electrical stimulation on contralateral DNLL, 95% of the inhibited IC neurons and 86% of the facilitated IC neurons showed plastic changes. Moreover, 1 h after the contralateral DNLL stimulation was stopped, the plastic changes in 74% of the inhibited IC neurons vanished, but still were maintained in 26% of the inhibited IC neurons. These results suggest that the contralateral DNLL ascending input can induce plastic changes of IC neurons, and this kind of effect can be maintained for a certain period of time, which is beneficial to enhance the sound intensity sensitivity of IC neurons.

PMID: 29691577 [PubMed - in process]



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[Subtypes of muscarinic acetylcholine receptors involved in the persistent activity of layer V pyramidal neurons in the primary auditory cortex of young mice].

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[Subtypes of muscarinic acetylcholine receptors involved in the persistent activity of layer V pyramidal neurons in the primary auditory cortex of young mice].

Sheng Li Xue Bao. 2018 Apr 25;70(2):123-131

Authors: Jia HJ, Wang X, Fu X, DU XF, Zheng WW, Luo F

Abstract
Cholinergic receptor activation and intracellular current injection lead to the persistent activity (PA), which may be involved in inducing neural plasticity. Our previous study showed that PA is closely related to the activation of muscarinic acetylcholine receptors (mAChRs) in pyramidal neurons of mouse primary auditory cortex (AI). However, the subtypes of mAChRs involved in PA remain unclear. Thus, using whole-cell patch-clamp recording and pharmacological methods, we investigated the role of different mAChR subtypes in inducing PA in AI layer V pyramidal neurons of young mice. The results showed that activation of mAChRs with intracellular depolarizing current induced PA in layer V pyramidal neurons. Blockade of M1, M2 or M3 subtypes prevented the PA, whereas M4 receptor antagonists did not affect the production of PA. The results suggest that the PA may be induced through a mechanism involving M1, M2 and M3 muscarinic receptors, but not M4 subtype.

PMID: 29691576 [PubMed - in process]



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[Protective effects of endogenous carbon monoxide against myocardial ischemia-reperfusion injury in rats].

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[Protective effects of endogenous carbon monoxide against myocardial ischemia-reperfusion injury in rats].

Sheng Li Xue Bao. 2018 Apr 25;70(2):115-122

Authors: Zhou Z, Ma S, Liu J, Ji QR, Cao CZ, Li XN, Tang F, Zhang W

Abstract
The present study is aimed to explore the effects of endogenous carbon monoxide on the ischemia-reperfusion in rats. Wistar rats were intraperitoneally injected with protoporphyrin cobalt chloride (CoPP, an endogenous carbon monoxide agonist, 5 mg/kg), zinc protoporphyrin (ZnPP, an endogenous carbon monoxide inhibitor, 5 mg/kg) or saline. Twenty-four hours after injection, the myocardial ischemia-reperfusion model was made by Langendorff isolated cardiac perfusion system, and cardiac function parameters were collected. Myocardial cGMP content was measured by ELISA, and the endogenous carbon monoxide in plasma and myocardial enzymes in perfusate at 10 min after reperfusion were measured by colorimetry. The results showed that before ischemia the cardiac functions of CoPP, ZnPP and control groups were stable, and there were no significant differences. After reperfusion, cardiac functions had significant differences among the three groups (P < 0.05). Compared with pre-ischemia, the cardiac function decreased and obvious cardiac arrest was shown in control and ZnPP groups, while the cardiac function in CoPP group did not change significantly, maintaining a relatively stable level. At the same time, three groups' carbon monoxide level, myocardial enzymology and the cardiac function recovery time after reperfusion also had significant differences (P < 0.05). Compared with those in control group, recovery after reperfusion was faster, activities of creatine kinase and lactic dehydrogenase were significantly decreased, plasma CO and myocardial cGMP contents were significantly increased in CoPP group, while these changes were completely opposite in ZnPP group. It is concluded that endogenous carbon monoxide can maintain cardiac function, shorten the time of cardiac function recovery, and play a protective role in cardiac ischemia-reperfusion.

PMID: 29691575 [PubMed - in process]



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[Electrophysiological characteristics of hippocampal postnatal early development mediated by AMPA receptors in rats].

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[Electrophysiological characteristics of hippocampal postnatal early development mediated by AMPA receptors in rats].

Sheng Li Xue Bao. 2018 Apr 25;70(2):106-114

Authors: Chen XY, Zhang AF, Zhao W, Gao YD, Duan HM, Hao P, Yang ZY, Li XG

Abstract
The present study was aimed to investigate the electrophysiological characteristics of hippocampal postnatal early development mediated by α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors in rats. Forty-eight Wistar rats were divided into postnatal 0.5-, 1-, 2- and 3-month groups (n = 12). Spontaneous excitatory postsynaptic currents (sEPSCs) and field excitatory postsynaptic potentials (fEPSPs) mediated by AMPA receptors were recorded to evaluate the changes in the intrinsic membrane properties of hippocampal CA1 pyramidal neurons by using patch-clamp and MED64 planar microelectrode array technique respectively. The results showed that, during the period of postnatal 0.5-3 months, some of the intrinsic membrane properties of hippocampal CA1 pyramidal neurons, such as the membrane capacitance (Cm) and the resting membrane potential (RMP), showed no significant changes, while the membrane input resistance (Rin) and the time constant (τ) of the cells were decreased significantly. The amplitude, frequency and kinetics (both rise and decay times) of sEPSCs were significantly increased during the period of postnatal 0.5-1 month, but they were all decreased during the period of postnatal 1-3 months. In addition, the range of evoked fEPSPs in hippocamal CA1 region was significantly expanded, but the fEPSP amplitudes were decreased significantly during the period of postnatal 0.5-3 months. Furthermore, the evoked fEPSPs could be significantly inhibited by extracellular application of the AMPA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). These results suggest that AMPA receptor may act as a major type of excitatory receptor to regulate synaptic transmission and connections during the early stage of hippocampal postnatal development, which promotes the development and functional maturation of hippocampus in rats.

PMID: 29691574 [PubMed - in process]



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Apelin in the hypothalamic paraventricular nucleus improves cardiac function in surgical trauma rats.

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Apelin in the hypothalamic paraventricular nucleus improves cardiac function in surgical trauma rats.

Sheng Li Xue Bao. 2018 Apr 25;70(2):99-105

Authors: Zhang HH, Wang YJ, Zheng C, Wang MY, Zhu DN

Abstract
Apelin is a novel endogenous active peptide. The aim of this study is to investigate whether apelin in the paraventricular nucleus (PVN) can improve the cardiac function in rats subjected to thoracic surgery trauma, and whether it is involved in the protective effect of electro-acupuncture (EA). Sprague-Dawley rats were randomly divided into non-stressed group (control), thoracic surgical trauma stressed group (trauma) and bilateral Neiguan EA applied on thoracic surgical trauma stressed group (trauma + EA-PC 6). The mRNA expressions of apelin receptor (APJR) and apelin in the PVN were detected by real time-PCR. The exogenous apelin-13 (6 mmol/L, 0.1 μL) was microinjected into the rat PVN in the thoracic trauma group, and the effects of apelin-13 on the blood pressure (BP), heart rate (HR) and the discharge of rostral ventrolateral medulla (RVLM) neurons were observed through the simultaneous recording technology by polygraph. The results showed that the APJR mRNA expression was significantly decreased in the rats of trauma group as compared with that in the control group (P < 0.05), and a decline trend of apelin mRNA expression was also observed. EA application at bilateral Neiguan acupoints partially recovered the decline of APJR and apelin mRNA expression by the treatment of thoracic trauma. Both mean arterial pressure and HR in the thoracic surgical trauma group were significantly increased by the microinjection of exogenous apelin-13 into the PVN (P < 0.05), and the single-unit discharge rate of RVLM neurons also had an increasing trend. These results suggest that apelin in the PVN can improve the cardiac function of thoracic surgical trauma rats, and may be involved in the protective effects of EA.

PMID: 29691573 [PubMed - in process]



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A sustainable model for cochlear implantation in the developing world: perspectives from the Indian subcontinent

Purpose of review The overall prevalence of deafness in India is 0.2%, but the prevalence in the southern state of Tamil Nadu is much higher (around 0.6%) because of consanguinity. Especially in India, establishing cochlear implantation as a treatment modality for hearing loss has been a daunting task, but in the last decade, the cochlear implantation program has emerged as an unqualified success in many states, with over 20 000 cochlear implantations done till date. Several states are sponsoring free implants to children under the age of 6 years and below poverty line. Recent findings Nearly 3000 cochlear implantations have been performed in Tamil Nadu under the Chief Minister's Comprehensive Health Insurance Scheme, with the goal to have a 'deafness free Tamil Nadu' by 2025. This scheme covers nearly 40 million people in rural areas. Valuable lessons have been learnt from this social experiment. One of the cornerstones of this scheme is the method to deliver habilitation via satellite centers in rural areas at the doorstep of the patient. The outcomes in peripheral centers were found to be statistically similar to those in the main center and correlated well with duration of habilitation. Summary Opening up satellite centers for habilitation across the state of Tamil Nadu has greatly helped to improve the attendance and outcomes. The Indian model has been hugely successful and has helped start similar cochlear implantation programs in neighboring countries such as Nepal, Sri Lanka and Bangladesh. Correspondence to Prof. Mohan Kameswaran, Department of Neurotology and Auditory Implants, Madras ENT Research Foundation, No. 1, First Cross Street, Off. Second Main Road, Raja Annamalai Puram, Chennai 600028, Tamil Nadu, India. Tel: +91 44 24311411x412x413x414x415; fax: +91 4424311416; e-mail: merfmk30@yahoo.com Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.

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What's what in auditory cortices?

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Publication date: 1 August 2018
Source:NeuroImage, Volume 176
Author(s): Chrysa Retsa, Pawel J. Matusz, Jan W.H. Schnupp, Micah M. Murray
Distinct anatomical and functional pathways are postulated for analysing a sound's object-related ('what') and space-related ('where') information. It remains unresolved to which extent distinct or overlapping neural resources subserve specific object-related dimensions (i.e. who is speaking and what is being said can both be derived from the same acoustic input). To address this issue, we recorded high-density auditory evoked potentials (AEPs) while participants selectively attended and discriminated sounds according to their pitch, speaker identity, uttered syllable ('what' dimensions) or their location ('where'). Sound acoustics were held constant across blocks; the only manipulation involved the sound dimension that participants had to attend to. The task-relevant dimension was varied across blocks. AEPs from healthy participants were analysed within an electrical neuroimaging framework to differentiate modulations in response strength from modulations in response topography; the latter of which forcibly follow from changes in the configuration of underlying sources. There were no behavioural differences in discrimination of sounds across the 4 feature dimensions. As early as 90ms post-stimulus onset, AEP topographies differed across 'what' conditions, supporting a functional sub-segregation within the auditory 'what' pathway. This study characterises the spatio-temporal dynamics of segregated, yet parallel, processing of multiple sound object-related feature dimensions when selective attention is directed to them.



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Warnings and caveats in brain controllability

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Publication date: 1 August 2018
Source:NeuroImage, Volume 176
Author(s): Chengyi Tu, Rodrigo P. Rocha, Maurizio Corbetta, Sandro Zampieri, Marco Zorzi, S. Suweis
A recent article by Gu et al. (Nat. Commun. 6, 2015) proposed to characterize brain networks, quantified using anatomical diffusion imaging, in terms of their "controllability", drawing on concepts and methods of control theory. They reported that brain activity is controllable from a single node, and that the topology of brain networks provides an explanation for the types of control roles that different regions play in the brain. In this work, we first briefly review the framework of control theory applied to complex networks. We then show contrasting results on brain controllability through the analysis of five different datasets and numerical simulations. We find that brain networks are not controllable (in a statistical significant way) by one single region. Additionally, we show that random null models, with no biological resemblance to brain network architecture, produce the same type of relationship observed by Gu et al. between the average/modal controllability and weighted degree. Finally, we find that resting state networks defined with fMRI cannot be attributed specific control roles. In summary, our study highlights some warning and caveats in the brain controllability framework.



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Network specialization during adolescence: Hippocampal effective connectivity in boys and girls

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Publication date: 15 July 2018
Source:NeuroImage, Volume 175
Author(s): Jeffrey D. Riley, E. Elinor Chen, Jessica Winsell, Elysia Poggi Davis, Laura M. Glynn, Tallie Z. Baram, Curt A. Sandman, Steven L. Small, Ana Solodkin
Adolescence is a complex period of concurrent mental and physical development that facilitates adult functioning at multiple levels. Despite the growing number of neuroimaging studies of cognitive development in adolescence focusing on regional activation patterns, there remains a paucity of information about the functional interactions across these participating regions that are critical for cognitive functioning, including memory. The current study used structural equation modeling (SEM) to determine how interactions among brain regions critical for memory change over the course of adolescence. We obtained functional MRI in 77 individuals aged 8–16 years old, divided into younger (ages 8–10) and older (ages > 11) cohorts, using an incidental encoding memory task to activate hippocampus formation and associated brain networks, as well as behavioral data on memory function. SEM was performed on the imaging data for four groups (younger girls, younger boys, older girls, and older boys) that were subsequently compared using a stacked model approach. Significant differences were seen between the models for these groups. Younger boys had a predominantly posterior distribution of connections originating in primary visual regions and terminating on multi-modal processing regions. In older boys, there was a relatively greater anterior connection distribution, with increased effective connectivity within association and multi-modal processing regions. Connection patterns in younger girls were similar to those of older boys, with a generally anterior-posterior distributed network among sensory, multi-modal, and limbic regions. In contrast, connections in older girls were widely distributed but relatively weaker. Memory performance increased with age, without a significant difference between the sexes. These findings suggest a progressive reorganization among brain regions, with a commensurate increase in efficiency of cognitive functioning, from younger to older individuals in both girls and boys, providing insight into the age- and gender-specific processes at play during this critical transition period.



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The left inferior frontal gyrus: A neural crossroads between abstract and concrete knowledge

Publication date: 15 July 2018
Source:NeuroImage, Volume 175
Author(s): Pasquale Anthony Della Rosa, Eleonora Catricalà, Matteo Canini, Gabriella Vigliocco, Stefano F. Cappa
Evidence from both neuropsychology and neuroimaging suggests that different types of information are necessary for representing and processing concrete and abstract word meanings. Both abstract and concrete concepts, however, conjointly rely on perceptual, verbal and contextual knowledge, with abstract concepts characterized by low values of imageability (IMG) (low sensory-motor grounding) and low context availability (CA) (more difficult to contextualize). Imaging studies supporting differences between abstract and concrete concepts show a greater recruitment of the left inferior frontal gyrus (LIFG) for abstract concepts, which has been attributed either to the representation of abstract-specific semantic knowledge or to the request for more executive control than in the case of concrete concepts. We conducted an fMRI study on 27 participants, using a lexical decision task involving both abstract and concrete words, whose IMG and CA values were explicitly modelled in separate parametric analyses. The LIFG was significantly more activated for abstract than for concrete words, and a conjunction analysis showed a common activation for words with low IMG or low CA only in the LIFG, in the same area reported for abstract words. A regional template map of brain activations was then traced for words with low IMG or low CA, and BOLD regional time-series were extracted and correlated with the specific LIFG neural activity elicited for abstract words. The regions associated to low IMG, which were functionally correlated with LIFG, were mainly in the left hemisphere, while those associated with low CA were in the right hemisphere. Finally, in order to reveal which LIFG-related network increased its connectivity with decreases of IMG or CA, we conducted generalized psychophysiological interaction analyses. The connectivity strength values extracted from each region connected with the LIFG were correlated with specific LIFG neural activity for abstract words, and a regression analysis was conducted to highlight which areas recruited by low IMG or low CA predicted the greater activation of the IFG for abstract concepts. Only the left middle temporal gyrus/angular gyrus, known to be involved in semantic processing, was a significant predictor of LIFG activity differentiating abstract from concrete words.The results show that the abstract conceptual processing requires the interplay of multiple brain regions, necessary for both the intrinsic and extrinsic properties of abstract knowledge. The LIFG can be thus identified as the neural crossroads between different types of information equally necessary for representing processing and differentiating abstract concepts from concrete ones.



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