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

Αρχειοθήκη ιστολογίου

! # Ola via Alexandros G.Sfakianakis on Inoreader

Η λίστα ιστολογίων μου

Δευτέρα 9 Απριλίου 2018

Gain-of-function SNPs in NLRP3 and IL1B genes confer protection against obesity and T2D: undiscovered role of inflammasome genetics in metabolic homeostasis?



https://ift.tt/2GNbllp

IGF-1-based screening reveals a low prevalence of acromegaly in patients with obstructive sleep apnea

Abstract

Purpose

Recent epidemiologic studies suggest a high prevalence of acromegaly. The prevalence of obstructive sleep apnea syndrome (OSAS) in acromegaly patients ranges from 47 to 70%. A recent study identified 2 patients with acromegaly among 567 OSAS patients. However, it remains unclear whether screening for acromegaly among OSAS patients is necessary. The aim was to screen for acromegaly among OSAS patients by measuring IGF-1 levels and performing confirmatory tests if necessary.

Methods

We performed a prospective cross-sectional diagnostic study on the prevalence of acromegaly in patients with OSAS. A total of 507 patients with a confirmed diagnosis of OSAS (357 male, 150 female) were screened.

Results

Seven male and three female patients (1.97% of total) were positively screened for elevated IGF-1 levels. Nine out of ten patients suppressed growth hormone levels during OGTT excluding acromegaly, whereas one individual was identified to have acromegaly according to established criteria (1/507, prevalence 0.2%). Analysis of the data showed no correlation between elevated IGF-1 values and the severity of OSAS or BMI.

Conclusions

Our data demonstrate a low prevalence of acromegaly in patients with OSAS. Until data from population-based studies is available we suggest restricting screening for acromegaly in OSAS to those patients who have additional clinical features of acromegaly.



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The associations of metabolic syndrome with incident hypertension, type 2 diabetes mellitus and chronic kidney disease: a cohort study

Abstract

Purpose

Metabolic syndrome (MetS) has been extensively studied for its long-term health effects, typically through conventional Cox proportional hazards regression modeling of the overall association of MetS with a single outcome. Such an approach neglects the inherent links between MetS-related disease outcomes and fails to provide sufficient insights into the impact of each component of MetS over time.

Methods

We therefore conducted a retrospective cohort study of 63,680 individuals who received health check-ups at the MJ Health Screening Center in Taiwan from 1997–2005 to study the subsequent risks of hypertension, type 2 diabetes mellitus (T2DM) and chronic kidney disease (CKD) simultaneously for MetS and its components. Multivariate-adjusted hazard ratios (HRs) were calculated using Cox models for multiple failure outcomes.

Results

At baseline, MetS was identified in 7835 participants. Over a median follow-up of 3 years, 8252, 1634, and 6714 participants developed hypertension, T2DM and CKD, respectively. The HR for MetS was 2.41 (95% CI 2.29–2.53) for hypertension, 5.17 (95% CI 4.68–5.71) for T2DM and 1.22 (95% CI 1.15–1.31) for CKD. Three MetS components showed the strongest association with each of the outcomes: elevated blood pressure with hypertension (HR = 3.62, 95% CI 3.46–3.79), raised fasting plasma glucose with T2DM (HR = 8.89, 95% CI 7.86–10.06) and elevated triglycerides with CKD (HR = 1.14, 95% CI 1.08–1.21).

Conclusions

MetS may help identify individuals with metabolic profiles that confer incremental risks for multiple diseases. Additionally, several components of the syndrome should be considered by clinicians, as they show stronger associations with specific diseases than MetS.



https://ift.tt/2GP7jsz

Pancreatic neuroendocrine tumors in MEN1 disease: a mono-centric longitudinal and prognostic study

Abstract

Purpose

Multiple endocrine neoplasia type 1 (MEN1) is an inherited endocrine neoplastic syndrome associated with a greater risk of endocrine tumor development like pancreatic neuroendocrine tumors (p-NET), with different clinical characteristics from sporadic ones. This paper aims to compare clinical, hystological and morphological aspects of p-NET in patients affected from MEN1 (MEN1+) and not-affected ones (MEN1−).

Methods

We performed a retrospective observational study. Data was collected between December 2010 and December 2015, including patients with a histological diagnosis of p-NET and radiological imaging. We compared clinical, histological, radiological, and prognostic aspects of MEN+ p-NET with MEN−1 p-NET.

Results

Of the 45 patients enrolled, 13 MEN1+ and 21 MEN1− cases were analyzed. Frequency of not secreting p-NETs and insulin secreting p-NETs, histopathological grades and Ki67 expression were superimposable between MEN1+ and MEN1− patients. MEN1+ pNETs are more often multicentric compared to MEN1− pNETs. Frequency of liver and nodes metastatic spread was higher in MEN1− p-NET compared to MEN1+ p-NET. Analyzing p-NET according to the disease outcome, we found that recovered and stable p-NETs in MEN1+ patients, compared to MEN1− cases, are diagnosed at lower age (p = 0.04/p = 0.002) and that are more frequently multifocal lesions (p = 0.009/p = 0.002).

Conclusions

In our study pNETs in MEN1+ and pNETs in MEN1− don't significantly differ for prognosis but only for clinical features. p-NET stage disease and prognosis can be positively influenced by early diagnosis and screening in index patients' first-degree relatives



https://ift.tt/2qlMb2a

Morphologic and molecular pathway of cushing syndrome cardiomyopathy



https://ift.tt/2GJkdIy

Complete evaluation of pituitary tumours in a single tertiary care institution

Abstract

Introduction

We retrospectively evaluated all patients with pituitary tumours treated in our department from 1/1/1997 to 01/11/2014.

Patients and methods

Two hundred and fifteen patients (124 females, 91 males, mean age 50.9 years) were treated because of pituitary tumours. All patients underwent basal hormonal analysis and when required dynamic testing in order to check for hormonal activity. Pituitary masses were divided into groups concerning their hormonal status and were further classified according to gender, age at diagnosis, tumour size, and the development of postoperative pituitary insufficiency when neurosurgical intervention was conducted.

Results

One hundred and twenty-one patients had hormonally inactive tumours (non-functional adenomas; 56.3%), 57 prolactinomas (26.5%), 17 growth hormone secreting adenomas (7.9%), 16 Cushing's disease (7.4%), and 4 craniopharyngiomas (1.9%). Tumours with maximum size <1 cm (microadenomas) were detected in 62 patients (28.8%) and ≥1 cm (macroadenomas) in 153 (71.2%) of all cases (rate 1:2.5). Ninty eight patients (45.6%) had surgery (87 transsphenoidal and 11 transcranial), of this group 34 with hormonally active tumours (37.8% of the 90 patients of this subcohort). Indications for surgery were an increased risk or manifestation of chiasma syndrome and clinical symptoms due to hormonal hypersecretion. Complete [32 cases (32.6%)] or partial [33 cases (33.7%)] postoperative insufficiency in minimum one pituitary axis was present in 65/98 (66.3%) of the operated patients.

Conclusions

Pituitary adenoma prevalence is rising due to widely available imaging procedures. The majority of the tumours in our cohort were macroadenomas and hormonally inactive. Tumour extirpation via the transsphenoidal or transcranial route resulted in functional pituitary impairment of variable extent in 2/3 of the patients.



https://ift.tt/2qlMaLE

Low-dose Synachten test with measurement of salivary cortisol in adult patients with β-thalassemia major

Abstract

Purpose

Beta-thalassemia major is a severe, congenital hematological disorder and, if untreated, leads to early mortality. Progress in therapeutical strategies improved clinical outcomes and life expectancy; however, increased survival led to the development of new disorders, including endocrinopathies. Little is known on the possible impairment of adrenocortical function, a potentially life-threatening condition, in long-term thalassaemic survivors. We therefore decided to assess adrenal reserve and the value of salivary cortisol during ACTH stimulation in the diagnosis of adrenocortical insufficiency in adult patients with β-thalassemia major.

Methods

Cross-sectional study including 72 adults with β-thalassemia major. Patients were tested with 1 µg ACTH for serum and salivary cortisol.

Results

Subnormal serum cortisol responses to ACTH stimulation (i.e., <500 nmol/l) were registered in 15 out of 72 patients. Salivary cortisol increased in parallel with serum cortisol and a clear-cut positive correlation was detected at each timepoint. Moreover, peak salivary cortisol values after ACTH stimulation were significantly lower in patients with impaired adrenal reserve (513.6 ± 52.33 vs. 914.1 ± 44.04 nmol/l p < 0.0001).

Conclusions

Our results attest to the need for testing for adrenal insufficiency among adult thalassaemic patients, as up to 20% presented impaired adrenal reserve. Salivary and serum cortisol levels during stimulation with ACTH were closely correlated and the use of salivary cortisol sampling during ACTH testing may represent a surrogate to serum cortisol in these patients.



https://ift.tt/2GMKiGC

Why Aren't There More Female Pain Medicine Physicians?

Despite a growing awareness about the importance of gender equity and the rising number of women in medicine, women remain persistently underrepresented in pain medicine and anesthesiology. Pain medicine ranks among the bottom quartile of medical specialties in terms of female applicants, female trainees, and proportion of female practitioners. Female pain medicine physicians are also notably disadvantaged compared with their male colleagues in most objective metrics of gender equity, which include financial compensation, career advancement, public recognition, and leadership positions. Increased gender diversity among pain medicine physicians is vital to fostering excellence in pain research, education, and clinical care, as well as creating a high-quality work environment. Pain medicine stands at a crossroads as a specialty, and must examine reasons for its current gender gap and consider a call to action to address this important issue. Accepted for publication December 24, 2017. Address correspondence to: Tina L. Doshi, MD, Division of Pain Medicine, Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, 550 N Broadway, Suite 309C, Baltimore, MD 21205 (e-mail: tina.doshi@jhmi.edu). The authors have no sources of funding to declare for this article. The authors declare no conflict of interest. Copyright © 2018 by American Society of Regional Anesthesia and Pain Medicine.

https://ift.tt/2GPCbJC

Quantitative analysis of surface recession on carbon-based ablators using a high-resolution non-contact profilometer

Publication date: 5 July 2018
Source:Materials & Design, Volume 149
Author(s): Soyoung Lim, Jae Hee Cheon, Myeong Jin Son, Eui Sup Shin
This paper proposes a systematic procedure for the quantitative analysis of the surface changes caused by ablation of carbon-based ablators using a high-resolution non-contact profilometer. The ablation tests were performed under high enthalpy flow conditions using a 0.4MW arc-heated wind tunnel. The high-resolution profilometer was used to measure the surface data of carbon-based ablators. The key parameters for the analysis of the surface changes, such as surface recession and roughness, were calculated by the proposed procedure. In addition, a finite element model of the sample after the ablation test was constructed from the measured surface data. The proposed procedure can be effectively used to perform various analyses of the ablated surface using the measured data and numerical analysis method.

Graphical abstract

image


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Transurethral vaporesection of prostate: diode laser or thulium laser?

Abstract

This study compared the safety and effectiveness of the diode laser and thulium laser during prostate transurethral vaporesection for treating benign prostate hyperplasia (BPH). We retrospectively analyzed 205 patients with BPH who underwent a diode laser or thulium laser technique for prostate transurethral vaporesection from June 2016 to June 2017 and who were followed up for 3 months. Baseline characteristics of the patients, perioperative data, postoperative outcomes, and complications were compared. We also assessed the International Prostate Symptom Score (IPSS), quality of life (QoL), maximum flow rate (Qmax), average flow rate (AFR), and postvoid residual volume (PVR) at 1 and 3 months postoperatively to evaluate the functional improvement of each group. There were no significant differences between the diode laser and thulium laser groups related to age, prostate volume, operative time, postoperative hospital stays, hospitalization costs, or perioperative data. The catheterization time was 3.5 ± 0.8 days for the diode laser group and 4.7 ± 1.8 days for the thulium laser group (p < 0.05). Each group had dramatic improvements in IPSS, QoL, Qmax, AFR, and PVR compared with the preoperative values (p < 0.05), although there were no significant differences between the two groups. Use of both diode laser and thulium laser contributes to safe, effective transurethral vaporesection in patients with symptomatic BPH. Diode laser, however, is better than thulium laser for prostate transurethral vaporesection because of its shorter catheterization time. The choice of surgical approach is more important than the choice of laser types during clinical decision making for transurethral laser prostatectomy.



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Obesity as a Disease, Not a Behavior.

Author: Gordon-Larsen, Penny PhD; Heymsfield, Steven B. MD
Page: 1543-1545


https://ift.tt/2HoKjhk

Will His Bundle Pacing Make Cardiac Resynchronization Therapy Obsolete?.

Author: Curtis, Anne B. MD
Page: 1546-1548


https://ift.tt/2uZxjvT

Risk Factors of Sudden Cardiac Death in the Young: Multiple-Year Community-Wide Assessment.

Author: Jayaraman, Reshmy MD; Reinier, Kyndaron MPH, PhD; Nair, Sandeep MD; Aro, Aapo L. MD, PhD; Uy-Evanado, Audrey MD; Rusinaru, Carmen MD, PhD; Stecker, Eric C. MD, MPH; Gunson, Karen MD; Jui, Jonathan MD, MPH; Chugh, Sumeet S. MD
Page: 1561-1570


https://ift.tt/2v3vFcG

Benefit of Adding Ezetimibe to Statin Therapy on Cardiovascular Outcomes and Safety in Patients With Versus Without Diabetes Mellitus: Results From IMPROVE-IT (Improved Reduction of Outcomes: Vytorin Efficacy International Trial).

Author: Giugliano, Robert P. MD, SM; Cannon, Christopher P. MD; Blazing, Michael A. MD; Nicolau, Jose C. MD; Corbalan, Ramon MD; Spinar, Jindrich MD; Park, Jeong-Gun PhD; White, Jennifer A. MS; Bohula, Erin A. MD, DPhil; Braunwald, Eugene MD; On behalf of the IMPROVE-IT (Improved Reduction of Outcomes: Vytorin Efficacy International Trial) Investigators
Page: 1571-1582


https://ift.tt/2HnOcDb

Surgical Enlargement of the Aortic Root Does Not Increase the Operative Risk of Aortic Valve Replacement.

Author: Rocha, Rodolfo V. MD; Manlhiot, Cedric PhD; Feindel, Christopher M. MD, MSc; Yau, Terrence M. MD, MSc; Mueller, Brigitte PhD; David, Tirone E. MD; Ouzounian, Maral MD, PhD
Page: 1585-1594


https://ift.tt/2Hn0bRn

Novel Desmin Mutation p.Glu401Asp Impairs Filament Formation, Disrupts Cell Membrane Integrity, and Causes Severe Arrhythmogenic Left Ventricular Cardiomyopathy/Dysplasia.

Author: Bermudez-Jimenez, Francisco Jose MD *,,,; Carriel, Victor MSc, MBiol, PhD *,,; Brodehl, Andreas MSc, PhD; Alaminos, Miguel MD, PhD; Campos, Antonio MD, PhD; Schirmer, Ilona MSc; Milting, Hendrik MSc, PhD; Abril, Beatriz Alvarez MD; Alvarez, Miguel MD, PhD; Lopez-Fernandez, Silvia MD; Garcia-Giustiniani, Diego MD; Monserrat, Lorenzo MD, PhD; Tercedor, Luis MD; Jimenez-Jaimez, Juan MD, PhD
Page: 1595-1610


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Arrhythmogenic Cardiomyopathy: Mechanotransduction Going Wrong.

Author: Mestroni, Luisa MD; Sbaizero, Orfeo PhD
Page: 1611-1613


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Leptin-Aldosterone-Neprilysin Axis: Identification of Its Distinctive Role in the Pathogenesis of the Three Phenotypes of Heart Failure in People With Obesity.

Author: Packer, Milton MD
Page: 1614-1631


https://ift.tt/2v3mr04

From the Literature.

Author: Hampton, Tracy PhD
Page: 1632-1633


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Wide QRS Complex After Catheter Ablation.

Author: Jennings, John MD; Jackman, Warren MD; Kay, G. Neal MD
Page: 1634-1637


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Sudden Cardiovascular Arrest During Sexual Intercourse.

Author: Sharifzadehgan, Ardalan MD, MPH; Marijon, Eloi MD, PhD; Bougouin, Wulfran MD, PhD; Karam, Nicole MD, PhD; Narayanan, Kumar MD, MPH; Waldmann, Victor MD, MPH; Lamhaut, Lionel MD, PhD; Jost, Daniel MD; Dumas, Florence MD, PhD; Cariou, Alain MD, PhD; Jouven, Xavier MD, PhD; On behalf of the Paris-SDEC Investigators
Page: 1638-1640


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Letter by Katritsis Regarding Article, "Preprints and Cardiovascular Science: Prescient or Premature?".

Author: Katritsis, Demosthenes G. MD, PhD
Page: 1641-1642


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Response by Nallamothu and Hill to Letter Regarding Article, "Preprints and Cardiovascular Science: Prescient or Premature?".

Author: Nallamothu, Brahmajee K. MD, MPH; Hill, Joseph A. MD
Page: 1643-1644


https://ift.tt/2HnNV37

Letter by Chertoff et al Regarding Article, "The Effects of Public Access Defibrillation on Survival After Out-of-Hospital Cardiac Arrest: A Systematic Review of Observational Studies".

Author: Chertoff, Jason MD, MPH; Mojadidi, Mohammad Khalid MD; Urbine, Daniel MD
Page: 1645


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Letter by El-Battrawy et al Regarding Article, "The Effects of Public Access Defibrillation on Survival After Out-of-Hospital Cardiac Arrest: A Systematic Review of Observational Studies".

Author: El-Battrawy, Ibrahim MD; Borggrefe, Martin MD; Akin, Ibrahim MD
Page: 1646-1647


https://ift.tt/2HntanZ

Letter by Karam et al Regarding Article, "The Effects of Public Access Defibrillation on Survival After Out-of-Hospital Cardiac Arrest: A Systematic Review of Observational Studies".

Author: Karam, Nicole MD, PhD; Jouven, Xavier MD, PhD; Marijon, Eloi MD, PhD
Page: 1648-1649


https://ift.tt/2uXgt0J

Response by Baekgaard et al to Letters Regarding Article, "The Effects of Public Access Defibrillation on Survival After Out-of-Hospital Cardiac Arrest: A Systematic Review of Observational Studies".

Author: Baekgaard, Josefine S. MD; Viereck, Soren MD, PhD; Moller, Thea Palsgaard MD, PhD; Ersboll, Annette Kjaer MSc, PhD; Lippert, Freddy MD; Folke, Fredrik MD, PhD
Page: 1650-1651


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Letter by Jin-shan and Xue-bin Regarding Article, "Acute Coronary Syndrome: What Is the Affected Artery? Where Is the Occlusion Located? And How Important Is the Myocardial Mass Involved?".

Author: Jin-shan, He MD; Xue-bin, Li MD
Page: 1652


https://ift.tt/2uWENQe

Monoclonal Antibody Against HA Protein of the European Avian-Like H1N1 Swine Influenza Virus

Monoclonal Antibodies in Immunodiagnosis and Immunotherapy, Ahead of Print.


https://ift.tt/2GKMBdj

A label-free cellulose SERS biosensor chip with improvement of nanoparticle-enhanced LSPR effects for early diagnosis of subarachnoid hemorrhage-induced complications

Publication date: 15 July 2018
Source:Biosensors and Bioelectronics, Volume 111
Author(s): Wansun Kim, Sung Ho Lee, Yong Jin Ahn, Seung Ho Lee, Jiwook Ryu, Seok Keun Choi, Samjin Choi
It is very difficult to predict some complications after subarachnoid hemorrhage (SAH), despite rapid advances in medical science. Herein, we introduce a label-free cellulose surface-enhanced Raman spectroscopy (SERS) biosensor chip with pH-functionalized, gold nanoparticle (AuNP)-enhanced localized surface plasmon resonance (LSPR) effects for identification of SAH-induced cerebral vasospasm and hydrocephalus caused by cerebrospinal fluid (CSF). The SERS biosensor chip was implemented by the synthesis reaction of the AuNPs, which were charged positively through pH level adjustment, onto a negatively-charged cellulose substrate with ξ = –30.7 mV. The zeta potential, nanostructural properties, nanocrystallinity, and computational calculation-based electric field distributions of the cellulose-originated AuNPs were optimized to maximize LSPR phenomena and then characterized. Additionally, the performance of the SERS biosensor was compared under two representative excitation laser sources in the visible region (532 nm) and near-infrared region (785 nm). The Raman activities of our SERS biosensor chip were evaluated by trace small molecules (crystal violet, 2 µL), and the biosensor achieved an enhancement factor of 3.29 × 109 for the analytic concept with an excellent reproducibility of 8.5% relative standard deviation and a detection limit of 0.74 pM. Furthermore, the experimental results revealed that the five proposed SERS-based biomarkers could provide important information for identifying and predicting SAH-induced cerebral vasospasm and hydrocephalus complications (91.1% reliability and 19.3% reproducibility). Therefore, this facile and effective principle of our SERS biosensor chip may inspire the basis and strategies for the development of sensing platforms to predict critical complications in various neurosurgical diagnoses.

Graphical abstract

image


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An Unexpected Donor Site Complication after Aesthetic Rhinoplasty: Arteriovenous Fistula of the Superficial Temporal Artery

10-1055-s-0038-1636934_170142let-1.jpg

Facial plast Surg 2018; 34: 235-236
DOI: 10.1055/s-0038-1636934



Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Article in Thieme eJournals:
Table of contents  |  Full text



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Halos and Asymmetric Triangles: Designing the Eyelids with Volume Using Fillers and/or Fat

Facial plast Surg 2018; 34: 173-177
DOI: 10.1055/s-0038-1636902

Periorbital aging is mainly a product of volume loss, which can be addressed with fillers and/or fat grafting. This stands in contrast to the lower face where a lifting procedure can be the principal method to improve moderate-to-significant aging. New models to explain these concepts of periorbital rejuvenation to both the surgeon and the prospective patient are outlined herein, namely, three facial halos (around the eyes, around the perimeter of the face, and around the mouth) and asymmetric triangles around the eyes. Specific techniques for fillers and fat grafting are also covered separately in detail in this article.
[...]

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Article in Thieme eJournals:
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The Aesthetics of the Upper Face and Brow: Male and Female Differences

Facial plast Surg 2018; 34: 114-118
DOI: 10.1055/s-0038-1636935

A hallmark of the modern era of facial plastic surgery is the increasing demand for upper facial rejuvenation by both genders and the growing variety of such options, including both surgical and non-surgical modalities. Thus, now more than ever, differentiating these aesthetic ideals between the two genders and understanding their nuances has become a necessity for the facial cosmetics community. In this article, a detailed comparison of the the pertinent anatomical and topographical differences is presented, followed by a review of the historical evolution of these aesthetic trends.
[...]

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Article in Thieme eJournals:
Table of contents  |  Abstract  |  Full text



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Aesthetics and Rejuvenation of the Temple

10-1055-s-0038-1636921_180003oa-1.jpg

Facial plast Surg 2018; 34: 159-163
DOI: 10.1055/s-0038-1636921

The temples are an often overlooked, but important element of facial rejuvenation. The anatomy of the temple should be understood prior to any intervention in this location. Multimodal treatment to re-establish youthful convexity, proper hairline position, and correct actinic damage is recommended for optimal results. Important anatomy, aesthetic goals, and methods of rejuvenation are reviewed in detail.
[...]

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Article in Thieme eJournals:
Table of contents  |  Abstract  |  Full text



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Upper Blepharoplasty: Management of the Upper Eyelid and Brow Complex via Transblepharoplasty Approach

Facial plast Surg 2018; 34: 183-193
DOI: 10.1055/s-0038-1636918

Upper blepharoplasty is one of the more common facial plastic procedures. The upper lid and brow complex are managed together. Whether upper blepharoplasty is performed for medical or cosmetic reasons, the aim is to improve appearance while retaining natural shape and maintaining (or improving) function. For optimal results, it is important to understand relevant eyelid anatomy and the concept of maintaining youthful volume and position of the eyelid brow orbit complex. Management of patient expectations, meticulous planning, and a degree of surgical finesse all contribute to the desired outcome. The article will focus on the assessment, techniques, and complications of upper blepharoplasty, which involve management of the skin, orbicularis oculi, preaponeurotic fat, levator aponeurosis and muscle as related to concomitant ptosis, and lateral brow complex via transblepharoplasty (internal) brow lift and fixation.
[...]

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Article in Thieme eJournals:
Table of contents  |  Abstract  |  Full text



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The Open Browlift

Facial plast Surg 2018; 34: 128-138
DOI: 10.1055/s-0038-1637003

The eyes and periorbital areas are critical components for the harmonious treatment of the aging face. The authors prefer the open browlift for rejuvenation of the forehead area. The open browlift is the most versatile, effective, and long-lasting method for the treatment of the forehead. The analysis of the forehead area, alternative treatments, variations in incisions, and key components of the surgical procedure are to be reviewed.
[...]

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Article in Thieme eJournals:
Table of contents  |  Abstract  |  Full text



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Hairline Restoration: Difference in Men and Woman—Length and Shape

Facial plast Surg 2018; 34: 155-158
DOI: 10.1055/s-0038-1636905

Hair restoration has become increasingly popular in recent years with both men and women. New technologies such as follicular unit extraction and grafting have made it possible for patients to get a natural looking result with minimal downtime. Men usually experience hairline recession as a result of androgenic alopecia, while women most commonly experience thinning of the crown and vertex, with the preservation of the hairline. However, there is a growing population of women who wish to advance their hairline forward because of congenital high hairline, traction alopecia, or previous facial cosmetic surgery. There are several key differences between the female and male hairline. Understanding such differences and following certain guidelines will help the facial plastic surgeon to obtain beautiful and natural appearing results.
[...]

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Article in Thieme eJournals:
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Endoscopic Browplasty

Facial plast Surg 2018; 34: 139-144
DOI: 10.1055/s-0038-1637728

The endoscopic brow lift has become an established procedure that can safely and reliably rejuvenate the upper third of the face. The authors discuss relevant anatomy and considerations for patient selection to optimize surgical outcomes. A detailed review of surgical technique is presented, and the potential complications and means to reduce them are discussed.
[...]

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Article in Thieme eJournals:
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Fat Grafting Volume Restoration to the Brow and Temporal Regions

Facial plast Surg 2018; 34: 164-172
DOI: 10.1055/s-0038-1636922

Primary manifestations of facial aging are the reduction in subcutaneous tissue volume, especially the atrophy of fat as well as bone volume depletion which directly contribute to loss of support and laxity of the skin. Depressions and hollows develop with a visible disruption of the cosmetic facial aesthetic units resulting in harsh shadows. This is especially evident in the eyebrow and temporal regions which accentuate the appearance of brow ptosis and a hollow, almost cadaveric look to the temple. Restoration of volume to these areas has been shown to rejuvenate the upper face creating a softer, fuller, and more youthful appearance. Fat grafting by itself or in combination with upper facial surgical procedures plays a major role in the restoration of youthful facial qualities in this region.
[...]

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Article in Thieme eJournals:
Table of contents  |  Abstract  |  Full text



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Scalp Advancement and the Pretrichial Brow Lift

Facial plast Surg 2018; 34: 145-149
DOI: 10.1055/s-0038-1636920

This article will review considerations for scalp advancement, or forehead shortening, when done in combination with a brow lift. The author's technique for anterior hairline reshaping is presented with particular focus on simultaneous reduction of temporal recession.
[...]

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Article in Thieme eJournals:
Table of contents  |  Abstract  |  Full text



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Effect of Orbicularis Muscle Resection during Blepharoplasty on the Position of the Eyebrow

Facial plast Surg 2018; 34: 178-182
DOI: 10.1055/s-0038-1636904

Dermatochalasis is a skin excess in the upper eyelid which may be associated with either an aesthetic and functional defect, blocking the peripheral vision. Upper blepharoplasty is the gold standard procedure for correction of dermatochalasis and to restore youthful contours to the periorbita. It is one of the most commonly performed procedures in aesthetic plastic surgery; however, there is still a lack of consensus about this procedure. The excess skin is sometimes removed alone or in conjunction with a strip of orbicularis oculi muscle. The rationale for both muscle and skin resection or skin alone preserving the muscle is uncertain. Some authors have studied the aging influence in brow position, and a few studies pointed out the influence of the upper blepharoplasty on brow height. The true effects, regarding the position of the eyebrow, of both techniques, with or without resection of the preseptal orbicularis oculi muscle, are unclear. The authors present a review of the literature to find the rationale for resecting or preserving the orbicularis oculi muscle in upper eyelid blepharoplasty and its relation to eyebrow position.
[...]

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

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The Trichophytic and Lateral Temporal Lifts: Application to the Focal Elevation of the Aging Lateral Eyebrow

Facial plast Surg 2018; 34: 150-154
DOI: 10.1055/s-0038-1636928

Rejuvenation of the upper face is a key component of overall facial rejuvenation. The upper face is probably the most important purveyor of our sense of well-being and our primary transmittal of nonverbal social interaction. There are many aspects to the aging changes in the area. Central to these concerns is the level and shape of the eyebrow. Ptosis of the lateral brow begins at a relatively young age and tends to worsen over time. This article describes an adaptation of modifiable techniques to address focal issues of the lateral eyebrow.
[...]

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Article in Thieme eJournals:
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The Aesthetics of the Upper Face: Forehead, Brow, and Upper Eyelid

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Facial plast Surg 2018; 34: 107-108
DOI: 10.1055/s-0038-1636923



Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Article in Thieme eJournals:
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Manipulation of the Periorbital Musculature

Facial plast Surg 2018; 34: 194-200
DOI: 10.1055/s-0038-1636919

The resting and expressive states of the periorbital region contribute to perceived age, emotion, gender, race, and countenance. A thorough understanding of the periorbital musculature is essential for comprehensive facial rejuvenation. Surgical and nonsurgical manipulation of these muscles can lead to alterations in brow elevation, resting brow position, and dynamic periorbital rhytids. Both surgical and nonsurgical techniques can produce desired effects, and they are often used concomitantly to obtain optimal results.
[...]

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Article in Thieme eJournals:
Table of contents  |  Abstract  |  Full text



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Editorial Board

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Publication date: June 2018
Source:Biomaterials, Volume 168





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More Rules, Still Exceptions: Understanding Immunomodulatory Antibody Activity In Vivo

Publication date: 9 April 2018
Source:Cancer Cell, Volume 33, Issue 4
Author(s): Andrea Ipsen-Escobedo, Falk Nimmerjahn
Understanding how agonistic and checkpoint control antibodies mediate their activity in vivo is essential for further development of these promising anti-cancer therapies. In this issue of Cancer Cell, studies by Vargas et al. and Yu et al. provide insights into the mode of action of CTLA-4- and CD40-specific antibodies.

Teaser

Understanding how agonistic and checkpoint control antibodies mediate their activity in vivo is essential for further development of these promising anti-cancer therapies. In this issue of Cancer Cell, studies by Vargas et al. and Yu et al. provide insights into the mode of action of CTLA-4- and CD40-specific antibodies.


https://ift.tt/2Hbd96W

T Cell Dysfunction in Cancer

Publication date: 9 April 2018
Source:Cancer Cell, Volume 33, Issue 4
Author(s): Daniela S. Thommen, Ton N. Schumacher
Therapeutic reinvigoration of tumor-specific T cells has greatly improved clinical outcome in cancer. Nevertheless, many patients still do not achieve durable benefit. Recent evidence from studies in murine and human cancer suggest that intratumoral T cells display a broad spectrum of (dys-)functional states, shaped by the multifaceted suppressive signals that occur within the tumor microenvironment. Here we discuss the current understanding of T cell dysfunction in cancer, the value of novel technologies to dissect such dysfunction at the single cell level, and how our emerging understanding of T cell dysfunction may be utilized to develop personalized strategies to restore antitumor immunity.

Teaser

Therapeutic reinvigoration of tumor-specific T cells has greatly improved clinical outcome in cancer. Nevertheless, many patients still do not achieve durable benefit. Recent evidence from studies in murine and human cancer suggest that intratumoral T cells display a broad spectrum of (dys-)functional states, shaped by the multifaceted suppressive signals that occur within the tumor microenvironment. Here we discuss the current understanding of T cell dysfunction in cancer, the value of novel technologies to dissect such dysfunction at the single cell level, and how our emerging understanding of T cell dysfunction may be utilized to develop personalized strategies to restore antitumor immunity.


https://ift.tt/2GOaQ6z

The Immune Revolution: A Case for Priming, Not Checkpoint

Publication date: 9 April 2018
Source:Cancer Cell, Volume 33, Issue 4
Author(s): Robert H. Vonderheide
Most tumors are unresponsive to immune checkpoint blockade, especially if deep immunosuppression in the tumor develops prior to and prevents T cell immunosurveillance. Failed or frustrated T cell priming often needs repair before successful sensitization to PD-1/PD-L1 blockade. CD40 activation plays a critical role in generating T cell immunity, by activating dendritic cells, and converting cold tumors to hot. In preclinical studies, agonistic CD40 antibodies demonstrate T cell-dependent anti-tumor activity, especially in combination with chemotherapy, checkpoint inhibitory antibodies, and other immune modulators. With the advent of multiple CD40 agonists with acceptable single-agent toxicity, clinical evaluation of CD40 combinations has accelerated.

Teaser

Most tumors are unresponsive to immune checkpoint blockade, especially if deep immunosuppression in the tumor develops prior to and prevents T cell immunosurveillance. Failed or frustrated T cell priming often needs repair before successful sensitization to PD-1/PD-L1 blockade. CD40 activation plays a critical role in generating T cell immunity, by activating dendritic cells, and converting cold tumors to hot. In preclinical studies, agonistic CD40 antibodies demonstrate T cell-dependent anti-tumor activity, especially in combination with chemotherapy, checkpoint inhibitory antibodies, and other immune modulators. With the advent of multiple CD40 agonists with acceptable single-agent toxicity, clinical evaluation of CD40 combinations has accelerated.


https://ift.tt/2HcnlMG

The Influence of the Gut Microbiome on Cancer, Immunity, and Cancer Immunotherapy

Publication date: 9 April 2018
Source:Cancer Cell, Volume 33, Issue 4
Author(s): Vancheswaran Gopalakrishnan, Beth A. Helmink, Christine N. Spencer, Alexandre Reuben, Jennifer A. Wargo
The microbiome is receiving significant attention given its influence on a host of human diseases including cancer. Its role in response to cancer treatment is becoming increasingly apparent, with evidence suggesting that modulating the gut microbiome may affect responses to numerous forms of cancer therapy. A working knowledge of the microbiome is vital as we move forward in this age of precision medicine, and an understanding of the microbiome's influence on immune responses and cancer is key. It is also important to understand factors influencing the gut microbiome and strategies to manipulate the microbiome to augment therapeutic responses.

Teaser

The microbiome is receiving significant attention given its influence on a host of human diseases including cancer. Its role in response to cancer treatment is becoming increasingly apparent, with evidence suggesting that modulating the gut microbiome may affect responses to numerous forms of cancer therapy. A working knowledge of the microbiome is vital as we move forward in this age of precision medicine, and an understanding of the microbiome's influence on immune responses and cancer is key. It is also important to understand factors influencing the gut microbiome and strategies to manipulate the microbiome to augment therapeutic responses.


https://ift.tt/2GOaL2L

Emerging Concepts for Immune Checkpoint Blockade-Based Combination Therapies

Publication date: 9 April 2018
Source:Cancer Cell, Volume 33, Issue 4
Author(s): Roberta Zappasodi, Taha Merghoub, Jedd D. Wolchok
Checkpoint blockade has formally demonstrated that reactivating anti-tumor immune responses can regress tumors. However, this only occurs in a fraction of patients. Incorporating these therapies in more powerful combinations is thus a logical next step. Here, we review functional roles of immune checkpoints and molecular determinants of checkpoint-blockade clinical activity. Limited-size T cell-infiltrated tumors, differing substantially from "self," generally respond to checkpoint blockade. Therefore, we propose that reducing tumor burden and increasing tumor immunogenicity are key factors to improve immunotherapy. Lastly, we outline criteria to select proper immunotherapy combination partners and highlight the importance of activity biomarkers for timely treatment optimization.

Teaser

Checkpoint blockade has formally demonstrated that reactivating anti-tumor immune responses can regress tumors. However, this only occurs in a fraction of patients. Incorporating these therapies in more powerful combinations is thus a logical next step. Here, we review functional roles of immune checkpoints and molecular determinants of checkpoint-blockade clinical activity. Limited-size T cell-infiltrated tumors, differing substantially from "self," generally respond to checkpoint blockade. Therefore, we propose that reducing tumor burden and increasing tumor immunogenicity are key factors to improve immunotherapy. Lastly, we outline criteria to select proper immunotherapy combination partners and highlight the importance of activity biomarkers for timely treatment optimization.


https://ift.tt/2HcngZo

Mechanistic Insights into Transmissible Cancers of Mammals

Publication date: 9 April 2018
Source:Cancer Cell, Volume 33, Issue 4
Author(s): Susan Bullman, Tao Zou, Matthew Meyerson
Transmissible cancers are clonal lineages that spread through populations via contagious cancer cells. In this issue of Cancer Cell, two articles by Stammnitz et al. and Frampton et al. present novel insights into the potential mechanisms underlying the propagation of naturally occurring transmissible cancers in mammals.

Teaser

Transmissible cancers are clonal lineages that spread through populations via contagious cancer cells. In this issue of Cancer Cell, two articles by Stammnitz et al. and Frampton et al. present novel insights into the potential mechanisms underlying the propagation of naturally occurring transmissible cancers in mammals.


https://ift.tt/2IGDPK9

Oncolytic Viruses as Antigen-Agnostic Cancer Vaccines

Publication date: 9 April 2018
Source:Cancer Cell, Volume 33, Issue 4
Author(s): Stephen J. Russell, Glen N. Barber
Selective destruction of neoplastic tissues by oncolytic viruses (OVs) leads to antigen-agnostic boosting of neoantigen-specific cytotoxic T lymphocyte (CTL) responses, making OVs ideal companions for checkpoint blockade therapy. Here we discuss the mechanisms whereby OVs modulate both adjuvanticity and antigenicity of tumor cells. Suppression of antitumor immunity after OV therapy has not been observed, possibly because viral antigen expression diminishes as the antiviral response matures, thereby progressively honing the CTL response to tumor neoantigens. By combining direct in situ tumor destruction with the ability to boost antitumor immunity, OVs also have the potential to be powerful standalone cancer therapies.



https://ift.tt/2HcncJ8

The Origins and Vulnerabilities of Two Transmissible Cancers in Tasmanian Devils

Publication date: 9 April 2018
Source:Cancer Cell, Volume 33, Issue 4
Author(s): Maximilian R. Stammnitz, Tim H.H. Coorens, Kevin C. Gori, Dane Hayes, Beiyuan Fu, Jinhong Wang, Daniel E. Martin-Herranz, Ludmil B. Alexandrov, Adrian Baez-Ortega, Syd Barthorpe, Alexandra Beck, Francesca Giordano, Graeme W. Knowles, Young Mi Kwon, George Hall, Stacey Price, Ruth J. Pye, Jose M.C. Tubio, Hannah V.T. Siddle, Sukhwinder Singh Sohal, Gregory M. Woods, Ultan McDermott, Fengtang Yang, Mathew J. Garnett, Zemin Ning, Elizabeth P. Murchison
Transmissible cancers are clonal lineages that spread through populations via contagious cancer cells. Although rare in nature, two facial tumor clones affect Tasmanian devils. Here we perform comparative genetic and functional characterization of these lineages. The two cancers have similar patterns of mutation and show no evidence of exposure to exogenous mutagens or viruses. Genes encoding PDGF receptors have copy number gains and are present on extrachromosomal double minutes. Drug screening indicates causative roles for receptor tyrosine kinases and sensitivity to inhibitors of DNA repair. Y chromosome loss from a male clone infecting a female host suggests immunoediting. These results imply that Tasmanian devils may have inherent susceptibility to transmissible cancers and present a suite of therapeutic compounds for use in conservation.

Graphical abstract

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Teaser

Stammnitz et al. show that the two transmissible cancer clones that affect Tasmanian devils are very similar in their tissues-of-origin, mutational patterns and driver gene candidates. Importantly, these cancers are both highly sensitive to inhibitors of some receptor tyrosine kinases as well as to inhibitors of DNA repair.


https://ift.tt/2GLicaJ

Molecular Signatures of Regression of the Canine Transmissible Venereal Tumor

Publication date: 9 April 2018
Source:Cancer Cell, Volume 33, Issue 4
Author(s): Dan Frampton, Hagen Schwenzer, Gabriele Marino, Lee M. Butcher, Gabriele Pollara, Janos Kriston-Vizi, Cristina Venturini, Rachel Austin, Karina Ferreira de Castro, Robin Ketteler, Benjamin Chain, Richard A. Goldstein, Robin A. Weiss, Stephan Beck, Ariberto Fassati
The canine transmissible venereal tumor (CTVT) is a clonally transmissible cancer that regresses spontaneously or after treatment with vincristine, but we know little about the regression mechanisms. We performed global transcriptional, methylation, and functional pathway analyses on serial biopsies of vincristine-treated CTVTs and found that regression occurs in sequential steps; activation of the innate immune system and host epithelial tissue remodeling followed by immune infiltration of the tumor, arrest in the cell cycle, and repair of tissue damage. We identified CCL5 as a possible driver of CTVT regression. Changes in gene expression are associated with methylation changes at specific intragenic sites. Our results underscore the critical role of host innate immunity in triggering cancer regression.

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Teaser

By analyzing serial biopsies of vincristine-treated canine transmissible venereal tumors, Frampton et al. show that tumor regression occurs in sequential steps involving the activation of the innate immune system and immune infiltration of the tumor, and they identify CCL5 as a possible driver of regression.


https://ift.tt/2Hcn64e

Dysregulated IL-18 Is a Key Driver of Immunosuppression and a Possible Therapeutic Target in the Multiple Myeloma Microenvironment

Publication date: 9 April 2018
Source:Cancer Cell, Volume 33, Issue 4
Author(s): Kyohei Nakamura, Sahar Kassem, Alice Cleynen, Marie-Lorraine Chrétien, Camille Guillerey, Eva Maria Putz, Tobias Bald, Irmgard Förster, Slavica Vuckovic, Geoffrey R. Hill, Seth L. Masters, Marta Chesi, P. Leif Bergsagel, Hervé Avet-Loiseau, Ludovic Martinet, Mark J. Smyth
Tumor-promoting inflammation and avoiding immune destruction are hallmarks of cancer. Here, we demonstrate that the pro-inflammatory cytokine interleukin (IL)-18 is critically involved in these hallmarks in multiple myeloma (MM). Mice deficient for IL-18 were remarkably protected from VkMYC MM progression in a CD8+ T cell-dependent manner. The MM-niche-derived IL-18 drove generation of myeloid-derived suppressor cells (MDSCs), leading to accelerated disease progression. A global transcriptome analysis of the immune microenvironment in 73 MM patients strongly supported the negative impact of IL-18-driven MDSCs on T cell responses. Strikingly, high levels of bone marrow plasma IL-18 were associated with poor overall survival in MM patients. Furthermore, our preclinical studies suggested that IL-18 could be a potential therapeutic target in MM.

Graphical abstract

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Teaser

Nakamura et al. show that IL-18 produced by the multiple myeloma (MM) niche promotes MM progression in a CD8+ T cell-dependent manner in a mouse model and that IL-18 could be a potential therapeutic target in MM. High levels of bone marrow plasma IL-18 are associated with poor overall survival in MM patients.


https://ift.tt/2IGDFT3

Adipocyte p62/SQSTM1 Suppresses Tumorigenesis through Opposite Regulations of Metabolism in Adipose Tissue and Tumor

Publication date: 9 April 2018
Source:Cancer Cell, Volume 33, Issue 4
Author(s): Jianfeng Huang, Angeles Duran, Miguel Reina-Campos, Tania Valencia, Elias A. Castilla, Timo D. Müller, Matthias H. Tschöp, Jorge Moscat, Maria T. Diaz-Meco
Obesity is a leading risk factor for cancer. However, understanding the crosstalk between adipocytes and tumor cells in vivo, independently of dietary contributions, is a major gap in the field. Here we used a prostate cancer (PCa) mouse model in which the signaling adaptor p62/Sqstm1 is selectively inactivated in adipocytes. p62 loss in adipocytes results in increased osteopontin secretion, which mediates tumor fatty acid oxidation and invasion, leading to aggressive metastatic PCa in vivo. Furthermore, p62 deficiency triggers in adipocytes a general shutdown of energy-utilizing pathways through mTORC1 inhibition, which supports nutrient availability for cancer cells. This reveals a central role of adipocyte's p62 in the symbiotic adipose tissue-tumor collaboration that enables cancer metabolic fitness.

Graphical abstract

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Teaser

Huang et al. show in a prostate cancer mouse model that p62 loss in adipocytes leads to aggressive disease by increasing osteopontin secretion, which mediates tumor fatty acid oxidation and invasion. P62 deficiency also represses energy-consuming pathways in adipocytes, increasing nutrient availability for tumors.


https://ift.tt/2Hcn0JU

Targeting the Senescence-Overriding Cooperative Activity of Structurally Unrelated H3K9 Demethylases in Melanoma

Publication date: 9 April 2018
Source:Cancer Cell, Volume 33, Issue 4
Author(s): Yong Yu, Kolja Schleich, Bin Yue, Sujuan Ji, Philipp Lohneis, Kristel Kemper, Mark R. Silvis, Nouar Qutob, Ellen van Rooijen, Melanie Werner-Klein, Lianjie Li, Dhriti Dhawan, Svenja Meierjohann, Maurice Reimann, Abdel Elkahloun, Steffi Treitschke, Bernd Dörken, Christian Speck, Frédérick A. Mallette, Leonard I. Zon, Sheri L. Holmen, Daniel S. Peeper, Yardena Samuels, Clemens A. Schmitt, Soyoung Lee




https://ift.tt/2IHQZGJ

Dual Targeting of Oncogenic Activation and Inflammatory Signaling Increases Therapeutic Efficacy in Myeloproliferative Neoplasms

Publication date: 9 April 2018
Source:Cancer Cell, Volume 33, Issue 4
Author(s): Maria Kleppe, Richard Koche, Lihua Zou, Peter van Galen, Corinne E. Hill, Lauren Dong, Sofie De Groote, Efthymia Papalexi, Amritha V. Hanasoge Somasundara, Keith Cordner, Matthew Keller, Noushin Farnoud, Juan Medina, Erin McGovern, Jaime Reyes, Justin Roberts, Matthew Witkin, Franck Rapaport, Julie Teruya-Feldstein, Jun Qi, Raajit Rampal, Bradley E. Bernstein, James E. Bradner, Ross L. Levine




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Modelling Motor Neuron Disease in Fruit Flies: Lessons from Spinal Muscular Atrophy

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Publication date: Available online 9 April 2018
Source:Journal of Neuroscience Methods
Author(s): Beppe Aquilina, Ruben J. Cauchi
Motor neuron disease (MND) is characterised by muscle weakness and paralysis downstream of motor neuron degeneration. Genetic factors play a major role in disease pathogenesis and progression. This is best underscored by spinal muscular atrophy (SMA), the most common MND affecting children. Although SMA is caused by homozygous mutations in the survival motor neuron 1 (SMN1) gene, partial compensation by the paralogous SMN2 gene and/or genetic modifiers influence age of onset and disease severity. SMA is also the first MND that is treatable thanks to the recent development of a molecular-based therapy. This key milestone was possible following an intense research campaign in which animal models had a starring role. In this review, we specifically focus on the fruit fly Drosophila melanogaster and highlight its sterling contributions aimed at furthering our understanding of SMA pathogenesis. Methods of gene disruption utilised to generate SMA fly models are discussed and ways through which neuromuscular defects have been characterised are elaborated on. A phenotypic overlap with patients and mammalian models, allowed the use of SMA fly models to identify genetic modifiers, hence spurring investigators to discover pathways that are perturbed in disease. Targeting these can potentially lead to complimentary therapies for SMA. The same output is expected from the use of SMA fly models to identify therapeutic compounds that have an ameliorative effect. We believe that lessons gained from SMA will allow researchers to eagerly exploit Drosophila to confirm novel genes linked to MND, reveal disease mechanisms and ultimately identify therapeutics.



https://ift.tt/2EBoLuU

Metastasis of Circulating Tumor Cells: Speed Matters

Publication date: 9 April 2018
Source:Developmental Cell, Volume 45, Issue 1
Author(s): Vanessa Morais Freitas, Georg Hilfenhaus, M. Luisa Iruela-Arispe
The mechanisms involved in tumor cell extravasation during metastasis remain incompletely understood. In this issue of Developmental Cell, Follain and colleagues (2018) demonstrate that blood flow velocity is an important regulator of circulating tumor cell exit from the bloodstream.

Teaser

The mechanisms involved in tumor cell extravasation during metastasis remain incompletely understood. In this issue of Developmental Cell, Follain and colleagues (2018) demonstrate that blood flow velocity is an important regulator of circulating tumor cell exit from the bloodstream.


https://ift.tt/2GJPMCd

Mitosis-Resistant Adhesions Provide Molecular Memory to Dividing Cells

Publication date: 9 April 2018
Source:Developmental Cell, Volume 45, Issue 1
Author(s): Guillaume Jacquemet, Johanna Ivaska
During mitosis, animal cells disassemble focal adhesions and round up while remaining attached to the substrata via actin cables and unknown adhesive structures. In this issue of Developmental Cell, Dix et al. (2018) describe integrin-positive adhesions, devoid of classical focal adhesion components, that persist throughout mitosis to contribute to re-spreading.

Teaser

During mitosis, animal cells disassemble focal adhesions and round up while remaining attached to the substrata via actin cables and unknown adhesive structures. In this issue of Developmental Cell, Dix et al. (2018) describe integrin-positive adhesions, devoid of classical focal adhesion components, that persist throughout mitosis to contribute to re-spreading.


https://ift.tt/2qkNQVt

A Tale of Two Cycles

Publication date: 9 April 2018
Source:Developmental Cell, Volume 45, Issue 1
Author(s): Kai Wang, John C. Larkin
Two of the fundamental rhythms of eukaryotic life are the circadian clock and the cell division cycle. In this issue of Developmental Cell, Fung-Uceda and colleagues (2018) have elucidated a molecular mechanism linking the circadian clock to the cell cycle in the plant Arabidopsis thaliana.

Teaser

Two of the fundamental rhythms of eukaryotic life are the circadian clock and the cell division cycle. In this issue of Developmental Cell, Fung-Uceda and colleagues (2018) have elucidated a molecular mechanism linking the circadian clock to the cell cycle in the plant Arabidopsis thaliana.


https://ift.tt/2GNraZm

Neurovascular Communication during CNS Development

Publication date: 9 April 2018
Source:Developmental Cell, Volume 45, Issue 1
Author(s): Isidora Paredes, Patricia Himmels, Carmen Ruiz de Almodóvar
A precise communication between the nervous and the vascular systems is crucial for proper formation and function of the central nervous system (CNS). Interestingly, this communication does not only occur by neural cells regulating the growth and properties of the vasculature, but new studies show that blood vessels actively control different neurodevelopmental processes. Here, we review the current knowledge on how neurons in particular influence growing blood vessels during CNS development and on how vessels participate in shaping the neural compartment. We also review the identified molecular mechanisms of this bidirectional communication.

Teaser

Paredes et al. review the bidirectional communication mechanisms between blood vessels and neurons. The authors focus particularly on the developmental aspect of this crosstalk in several areas of the brain and spinal cord.


https://ift.tt/2qkNKx5

Hemodynamic Forces Tune the Arrest, Adhesion, and Extravasation of Circulating Tumor Cells

Publication date: 9 April 2018
Source:Developmental Cell, Volume 45, Issue 1
Author(s): Gautier Follain, Naël Osmani, Ana Sofia Azevedo, Guillaume Allio, Luc Mercier, Matthia A. Karreman, Gergely Solecki, Marìa Jesùs Garcia Leòn, Olivier Lefebvre, Nina Fekonja, Claudia Hille, Vincent Chabannes, Guillaume Dollé, Thibaut Metivet, François Der Hovsepian, Christophe Prudhomme, Angélique Pichot, Nicodème Paul, Raphaël Carapito, Siamak Bahram, Bernhard Ruthensteiner, André Kemmling, Susanne Siemonsen, Tanja Schneider, Jens Fiehler, Markus Glatzel, Frank Winkler, Yannick Schwab, Klaus Pantel, Sébastien Harlepp, Jacky G. Goetz
Metastatic seeding is driven by cell-intrinsic and environmental cues, yet the contribution of biomechanics is poorly known. We aim to elucidate the impact of blood flow on the arrest and the extravasation of circulating tumor cells (CTCs) in vivo. Using the zebrafish embryo, we show that arrest of CTCs occurs in vessels with favorable flow profiles where flow forces control the adhesion efficacy of CTCs to the endothelium. We biophysically identified the threshold values of flow and adhesion forces allowing successful arrest of CTCs. In addition, flow forces fine-tune tumor cell extravasation by impairing the remodeling properties of the endothelium. Importantly, we also observe endothelial remodeling at arrest sites of CTCs in mouse brain capillaries. Finally, we observed that human supratentorial brain metastases preferably develop in areas with low perfusion. These results demonstrate that hemodynamic profiles at metastatic sites regulate key steps of extravasation preceding metastatic outgrowth.

Graphical abstract

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Teaser

Follain et al. demonstrate that blood flow forces tune both the arrest and extravasation of circulating tumor cells in vivo. Permissive flow forces allow stable intravascular arrest of circulating tumor cells. Flow forces drive endothelial remodeling around arrested tumor cells, favoring extravasation preceding metastatic outgrowth.


https://ift.tt/2GMA0GL

HCMV Assembly Is Totally Tubular

Publication date: 9 April 2018
Source:Developmental Cell, Volume 45, Issue 1
Author(s): Shelby M. Lyon, Robert F. Kalejta
Microtubules are normally organized at centrosomes, but other sites can also serve as microtubule organizing centers (MTOCs). In this issue of Developmental Cell, Procter et al. (2018) show that the human cytomegalovirus virion assembly compartment acts as a dynamic Golgi-derived MTOC where EB3 nucleates microtubules and regulates infectious virion production.

Teaser

Microtubules are normally organized at centrosomes, but other sites can also serve as microtubule organizing centers (MTOCs). In this issue of Developmental Cell, Procter et al. (2018) show that the human cytomegalovirus virion assembly compartment acts as a dynamic Golgi-derived MTOC where EB3 nucleates microtubules and regulates infectious virion production.


https://ift.tt/2qlCb99

Coordination of Receptor Tyrosine Kinase Signaling and Interfacial Tension Dynamics Drives Radial Intercalation and Tube Elongation

Publication date: 9 April 2018
Source:Developmental Cell, Volume 45, Issue 1
Author(s): Neil M. Neumann, Matthew C. Perrone, Jim H. Veldhuis, Robert J. Huebner, Huiwang Zhan, Peter N. Devreotes, G. Wayne Brodland, Andrew J. Ewald
We sought to understand how cells collectively elongate epithelial tubes. We first used 3D culture and biosensor imaging to demonstrate that epithelial cells enrich Ras activity, phosphatidylinositol (3,4,5)-trisphosphate (PIP3), and F-actin to their leading edges during migration within tissues. PIP3 enrichment coincided with, and could enrich despite inhibition of, F-actin dynamics, revealing a conserved migratory logic compared with single cells. We discovered that migratory cells can intercalate into the basal tissue surface and contribute to tube elongation. We then connected molecular activities to subcellular mechanics using force inference analysis. Migration and transient intercalation required specific and similar anterior-posterior ratios of interfacial tension. Permanent intercalations were distinguished by their capture at the boundary through time-varying tension dynamics. Finally, we integrated our experimental and computational data to generate a finite element model of tube elongation. Our model revealed that intercalation, interfacial tension dynamics, and high basal stress are together sufficient for mammary morphogenesis.

Graphical abstract

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Teaser

Neumann et al. demonstrate that the spatial asymmetries and molecular logic of migration are conserved between epithelial cells within mammalian tissues and single cells on flat substrates. Force inference techniques and finite element modeling further define a set of mechanical properties and cell behaviors, including radial intercalation, that elongate tubes.


https://ift.tt/2GOGAN2

The HCMV Assembly Compartment Is a Dynamic Golgi-Derived MTOC that Controls Nuclear Rotation and Virus Spread

Publication date: 9 April 2018
Source:Developmental Cell, Volume 45, Issue 1
Author(s): Dean J. Procter, Avik Banerjee, Masatoshi Nukui, Kevin Kruse, Vadim Gaponenko, Eain A. Murphy, Yulia Komarova, Derek Walsh
Human cytomegalovirus (HCMV), a leading cause of congenital birth defects, forms an unusual cytoplasmic virion maturation site termed the "assembly compartment" (AC). Here, we show that the AC also acts as a microtubule-organizing center (MTOC) wherein centrosome activity is suppressed and Golgi-based microtubule (MT) nucleation is enhanced. This involved viral manipulation of discrete functions of MT plus-end-binding (EB) proteins. In particular, EB3, but not EB1 or EB2, was recruited to the AC and was required to nucleate MTs that were rapidly acetylated. EB3-regulated acetylated MTs were necessary for nuclear rotation prior to cell migration, maintenance of AC structure, and optimal virus replication. Independently, a myristoylated peptide that blocked EB3-mediated enrichment of MT regulatory proteins at Golgi regions of the AC also suppressed acetylated MT formation, nuclear rotation, and infection. Thus, HCMV offers new insights into the regulation and functions of Golgi-derived MTs and the therapeutic potential of targeting EB3.

Teaser

Live-cell imaging reveals the dynamic nature of the human cytomegalovirus (HCMV) assembly compartment (AC), which acts as a Golgi-derived microtubule-organizing center. Specific recruitment of microtubule plus-end binding EB3 facilitates acetylated MT formation at the AC and nuclear rotation prior to cell migration. EB3 targeting with myristoylated peptides suppresses infection.


https://ift.tt/2qjUQCk

The RAB11A-Positive Compartment Is a Primary Platform for Autophagosome Assembly Mediated by WIPI2 Recognition of PI3P-RAB11A

Publication date: 9 April 2018
Source:Developmental Cell, Volume 45, Issue 1
Author(s): Claudia Puri, Mariella Vicinanza, Avraham Ashkenazi, Matthew J. Gratian, Qifeng Zhang, Carla F. Bento, Maurizio Renna, Fiona M. Menzies, David C. Rubinsztein
Autophagy is a critical pathway that degrades intracytoplasmic contents by engulfing them in double-membraned autophagosomes that are conjugated with LC3 family members. These membranes are specified by phosphatidylinositol 3-phosphate (PI3P), which recruits WIPI2, which, in turn, recruits ATG16L1 to specify the sites of LC3-conjugation. Conventionally, phosphatidylinositides act in concert with other proteins in targeting effectors to specific membranes. Here we describe that WIPI2 localizes to autophagic precursor membranes by binding RAB11A, a protein that specifies recycling endosomes, and that PI3P is formed on RAB11A-positive membranes upon starvation. Loss of RAB11A impairs the recruitment and assembly of the autophagic machinery. RAB11A-positive membranes are a primary direct platform for canonical autophagosome formation that enables autophagy of the transferrin receptor and damaged mitochondria. While this compartment may receive membrane inputs from other sources to enable autophagosome biogenesis, RAB11A-positive membranes appear to be a compartment from which autophagosomes evolve.

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Puri et al. report that key events preceding completion of autophagosome formation occur on a RAB11A- and transferrin receptor-positive membrane compartment, likely the recycling endosome. RAB11A recruits WIPI2 for ATG16L-mediated LC3 conjugation, suggesting that this RAB11A compartment, beyond contributing membrane to autophagosomes, is a primary platform on which autophagosomes form.


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The Role of Mitotic Cell-Substrate Adhesion Re-modeling in Animal Cell Division

Publication date: 9 April 2018
Source:Developmental Cell, Volume 45, Issue 1
Author(s): Christina L. Dix, Helen K. Matthews, Marina Uroz, Susannah McLaren, Lucie Wolf, Nicholas Heatley, Zaw Win, Pedro Almada, Ricardo Henriques, Michael Boutros, Xavier Trepat, Buzz Baum
Animal cells undergo a dramatic series of shape changes as they divide, which depend on re-modeling of cell-substrate adhesions. Here, we show that while focal adhesion complexes are disassembled during mitotic rounding, integrins remain in place. These integrin-rich contacts connect mitotic cells to the underlying substrate throughout mitosis, guide polarized cell migration following mitotic exit, and are functionally important, since adherent cells undergo division failure when removed from the substrate. Further, the ability of cells to re-spread along pre-existing adhesive contacts is essential for division in cells compromised in their ability to construct a RhoGEF-dependent (Ect2) actomyosin ring. As a result, following Ect2 depletion, cells fail to divide on small adhesive islands but successfully divide on larger patterns, as the connection between daughter cells narrows and severs as they migrate away from one another. In this way, regulated re-modeling of cell-substrate adhesions during mitotic rounding aids division in animal cells.

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Dix et al. show that the integrin-positive adhesive contacts that remain following mitotic rounding are essential for division in non-transformed adherent cells in culture. Further, these adhesion sites guide polarized daughter cell migration—a process that is sufficient to drive abscission in the absence of a visible contractile actomyosin ring.


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Bayesian convolutional neural network based MRI brain extraction on nonhuman primates

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Publication date: 15 July 2018
Source:NeuroImage, Volume 175
Author(s): Gengyan Zhao, Fang Liu, Jonathan A. Oler, Mary E. Meyerand, Ned H. Kalin, Rasmus M. Birn
Brain extraction or skull stripping of magnetic resonance images (MRI) is an essential step in neuroimaging studies, the accuracy of which can severely affect subsequent image processing procedures. Current automatic brain extraction methods demonstrate good results on human brains, but are often far from satisfactory on nonhuman primates, which are a necessary part of neuroscience research. To overcome the challenges of brain extraction in nonhuman primates, we propose a fully-automated brain extraction pipeline combining deep Bayesian convolutional neural network (CNN) and fully connected three-dimensional (3D) conditional random field (CRF). The deep Bayesian CNN, Bayesian SegNet, is used as the core segmentation engine. As a probabilistic network, it is not only able to perform accurate high-resolution pixel-wise brain segmentation, but also capable of measuring the model uncertainty by Monte Carlo sampling with dropout in the testing stage. Then, fully connected 3D CRF is used to refine the probability result from Bayesian SegNet in the whole 3D context of the brain volume. The proposed method was evaluated with a manually brain-extracted dataset comprising T1w images of 100 nonhuman primates. Our method outperforms six popular publicly available brain extraction packages and three well-established deep learning based methods with a mean Dice coefficient of 0.985 and a mean average symmetric surface distance of 0.220 mm. A better performance against all the compared methods was verified by statistical tests (all p-values < 10−4, two-sided, Bonferroni corrected). The maximum uncertainty of the model on nonhuman primate brain extraction has a mean value of 0.116 across all the 100 subjects. The behavior of the uncertainty was also studied, which shows the uncertainty increases as the training set size decreases, the number of inconsistent labels in the training set increases, or the inconsistency between the training set and the testing set increases.



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Conflict monitoring mechanism at the single-neuron level in the human ventral anterior cingulate cortex

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Publication date: 15 July 2018
Source:NeuroImage, Volume 175
Author(s): Irit Shapira-Lichter, Ido Strauss, Noga Oren, Tomer Gazit, Francesco Sammartino, Peter Giacobbe, Sidney Kennedy, William D. Hutchison, Itzhak Fried, Talma Hendler, Andres M. Lozano
Life requires monitoring and adjusting behavior in the face of conflicts. The conflict monitoring theory implicates the anterior cingulate cortex (ACC) in these processes; its ventral aspect (vACC) specializes in emotional conflict. To elucidate the underpinning neural mechanism, we recorded vACC extracellular activity from 12 patients with mood disorders or epilepsy who performed the face-emotional Stroop task. Behaviorally, both conflict detection and adaptation to conflict were evident. The firing rate of neurons in the vACC represented current conflict, i.e., current-congruency. The late onset of the effect is compatible with a role in monitoring. Additionally, early responses of some neurons represented the immediate history of conflicts, i.e., previous-trial-congruency. Finally, in some neurons the response to the current-trial was modulated by previous-trial-congruency, laying the ground for adjusting-to-conflicts. Our results uncover a single neuron level mechanism in the vACC that encodes and integrates past and present emotional conflicts, allowing humans to accommodate their responses accordingly.



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Intra-hemispheric integration underlies perception of tilt illusion

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Publication date: 15 July 2018
Source:NeuroImage, Volume 175
Author(s): Chen Song, Geraint Rees
The integration of inputs across the entire visual field into a single conscious experience is fundamental to human visual perception. This integrated nature of visual experience is illustrated by contextual illusions such as the tilt illusion, in which the perceived orientation of a central grating appears tilted away from its physical orientation, due to the modulation by a surrounding grating with a different orientation. Here we investigated the relative contribution of local, intra-hemispheric and global, inter-hemispheric integration mechanisms to perception of the tilt illusion. We used Dynamic Causal Modelling of fMRI signals to estimate effective connectivity in human early visual cortices (V1, V2, V3) during bilateral presentation of a tilt illusion stimulus. Our analysis revealed that neural responses associated with the tilt illusion were modulated by intra- rather than inter-hemispheric connectivity. Crucially, across participants, intra-hemispheric connectivity in V1 correlated with the magnitude of the tilt illusion, while no such correlation was observed for V1 inter-hemispheric connectivity, or V2, V3 connectivity. Moreover, when the illusion stimulus was presented unilaterally rather than bilaterally, the illusion magnitude did not change. Together our findings suggest that perception of the tilt illusion reflects an intra-hemispheric integration mechanism. This is in contrast to the existing literature, which suggests inter-hemispheric modulation of neural activity as early as V1. This discrepancy with our findings may reflect the diversity and complexity of integration mechanisms involved in visual processing and visual perception.



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Lateral prefrontal cortex lesion impairs regulation of internally and externally directed attention

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Publication date: 15 July 2018
Source:NeuroImage, Volume 175
Author(s): Julia W.Y. Kam, Anne-Kristin Solbakk, Tor Endestad, Torstein R. Meling, Robert T. Knight
Our capacity to flexibly shift between internally and externally directed attention is crucial for successful performance of activities in our daily lives. Neuroimaging studies have implicated the lateral prefrontal cortex (LPFC) in both internally directed processes, including autobiographical memory retrieval and future planning, and externally directed processes, including cognitive control and selective attention. However, the causal involvement of the LPFC in regulating internally directed attention states is unknown. The current study recorded scalp EEG from patients with LPFC lesions and healthy controls as they performed an attention task that instructed them to direct their attention either to the external environment or their internal milieu. We compared frontocentral midline theta and posterior alpha between externally and internally directed attention states. While healthy controls showed increased theta power during externally directed attention and increased alpha power during internally directed attention, LPFC patients revealed no differences between the two attention states in either electrophysiological measure in the analyzed time windows. These findings provide evidence that damage to the LPFC leads to dysregulation of both types of attention, establishing the important role of LPFC in supporting sustained periods of internally and externally directed attention.



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Statistical power comparisons at 3T and 7T with a GO / NOGO task

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Publication date: 15 July 2018
Source:NeuroImage, Volume 175
Author(s): Salvatore Torrisi, Gang Chen, Daniel Glen, Peter A. Bandettini, Chris I. Baker, Richard Reynolds, Jeffrey Yen-Ting Liu, Joseph Leshin, Nicholas Balderston, Christian Grillon, Monique Ernst
The field of cognitive neuroscience is weighing evidence about whether to move from standard field strength to ultra-high field (UHF). The present study contributes to the evidence by comparing a cognitive neuroscience paradigm at 3 Tesla (3T) and 7 Tesla (7T). The goal was to test and demonstrate the practical effects of field strength on a standard GO/NOGO task using accessible preprocessing and analysis tools. Two independent matched healthy samples (N = 31 each) were analyzed at 3T and 7T. Results show gains at 7T in statistical strength, the detection of smaller effects and group-level power. With an increased availability of UHF scanners, these gains may be exploited by cognitive neuroscientists and other neuroimaging researchers to develop more efficient or comprehensive experimental designs and, given the same sample size, achieve greater statistical power at 7T.



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Distinct phase-amplitude couplings distinguish cognitive processes in human attention

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Publication date: 15 July 2018
Source:NeuroImage, Volume 175
Author(s): Ravi V. Chacko, Byungchan Kim, Suh Woo Jung, Amy L. Daitch, Jarod L. Roland, Nicholas V. Metcalf, Maurizio Corbetta, Gordon L. Shulman, Eric C. Leuthardt
Spatial attention is the cognitive function that coordinates the selection of visual stimuli with appropriate behavioral responses. Recent studies have reported that phase-amplitude coupling (PAC) of low and high frequencies covaries with spatial attention, but differ on the direction of covariation and the frequency ranges involved. We hypothesized that distinct phase-amplitude frequency pairs have differentiable contributions during tasks that manipulate spatial attention. We investigated this hypothesis with electrocorticography (ECoG) recordings from participants who engaged in a cued spatial attention task. To understand the contribution of PAC to spatial attention we classified cortical sites by their relationship to spatial variables or behavioral performance. Local neural activity in spatial sites was sensitive to spatial variables in the task, while local neural activity in behavioral sites correlated with reaction time. We found two PAC frequency clusters that covaried with different aspects of the task. During a period of cued attention, delta-phase/high-gamma (DH) PAC was sensitive to cue direction in spatial sites. In contrast, theta-alpha-phase/beta-low-gamma-amplitude (TABL) PAC robustly correlated with future reaction times in behavioral sites. Finally, we investigated the origins of TABL PAC and found it corresponded to behaviorally relevant, sharp waveforms, which were also coupled to a low frequency rhythm. We conclude that TABL and DH PAC correspond to distinct mechanisms during spatial attention tasks and that sharp waveforms are elements of a coupled dynamical process.



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Can anomalous diffusion models in magnetic resonance imaging be used to characterise white matter tissue microstructure?

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Publication date: 15 July 2018
Source:NeuroImage, Volume 175
Author(s): Qiang Yu, David Reutens, Viktor Vegh
PurposeDuring the time window of diffusion weighted magnetic resonance imaging experiments (DW-MRI), water diffusion in tissue appears to be anomalous as a transient effect, with a mean squared displacement that is not a linear function of time. A number of statistical models have been proposed to describe water diffusion in tissue, and parameters describing anomalous as well as Gaussian diffusion have previously been related to measures of tissue microstructure such as mean axon radius. We analysed the relationship between white matter tissue characteristics and parameters of existing statistical diffusion models.MethodsA white matter tissue model (ActiveAx) was used to generate multiple b-value diffusion-weighted magnetic resonance imaging signals. The following models were evaluated to fit the diffusion signal: 1) Gaussian models - 1a) mono-exponential decay and 1b) bi-exponential decay; 2) Anomalous diffusion models - 2a) stretched exponential, 2b) continuous time random walk and 2c) space fractional Bloch-Torrey equation. We identified the best candidate model based on the relationship between the diffusion-derived parameters and mean axon radius and axial diffusivity, and applied it to the in vivo DW-MRI data acquired at 7.0 T from five healthy participants to estimate the same selected tissue characteristics. Differences between simulation parameters and fitted parameters were used to assess accuracy and in vivo findings were compared to previously reported observations.ResultsThe space fractional Bloch-Torrey model was found to be the best candidate in characterising white matter on the base of the ActiveAx simulated DW-MRI data. Moreover, parameters of the space fractional Bloch-Torrey model were sensitive to mean axon radius and axial diffusivity and exhibited low noise sensitivity based on simulations. We also found spatial variations in the model parameter β to reflect changes in mean axon radius across the mid-sagittal plane of the corpus callosum.ConclusionSimulations have been used to define how the parameters of the most common statistical magnetic resonance imaging diffusion models relate to axon radius and diffusivity. The space fractional Bloch-Torrey equation was identified as the best model for the characterisation of axon radius and diffusivity. This model allows changes in mean axon radius and diffusivity to be inferred from spatially resolved maps of model parameters.



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Distinctive heritability patterns of subcortical-prefrontal cortex resting state connectivity in childhood: A twin study

Publication date: 15 July 2018
Source:NeuroImage, Volume 175
Author(s): Michelle Achterberg, Marian J. Bakermans-Kranenburg, Marinus H. van Ijzendoorn, Mara van der Meulen, Nim Tottenham, Eveline A. Crone
Connectivity between limbic/subcortical and prefrontal-cortical brain regions develops considerably across childhood, but less is known about the heritability of these networks at this age. We tested the heritability of limbic/subcortical-cortical and limbic/subcortical-subcortical functional brain connectivity in 7- to 9-year-old twins (N = 220), focusing on two key limbic/subcortical structures: the ventral striatum and the amygdala, given their combined influence on changing incentivised behavior during childhood and adolescence. Whole brain analyses with ventral striatum (VS) and amygdala as seeds in genetically independent groups showed replicable functional connectivity patterns. The behavioral genetic analyses revealed that in general VS and amygdala connectivity showed distinct influences of genetics and environment. VS-prefrontal cortex connections were best described by genetic and unique environmental factors (the latter including measurement error), whereas amygdala-prefrontal cortex connectivity was mainly explained by environmental influences. Similarities were also found: connectivity between both the VS and amygdala and ventral anterior cingulate cortex (vACC) showed influences of shared environment, while connectivity with the orbitofrontal cortex (OFC) showed heritability. These findings may inform future interventions that target behavioral control and emotion regulation, by taking into account genetic dispositions as well as shared and unique environmental factors such as child rearing.



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Statistical learning of multisensory regularities is enhanced in musicians: An MEG study

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Publication date: 15 July 2018
Source:NeuroImage, Volume 175
Author(s): Evangelos Paraskevopoulos, Nikolas Chalas, Panagiotis Kartsidis, Andreas Wollbrink, Panagiotis Bamidis
The present study used magnetoencephalography (MEG) to identify the neural correlates of audiovisual statistical learning, while disentangling the differential contributions of uni- and multi-modal statistical mismatch responses in humans. The applied paradigm was based on a combination of a statistical learning paradigm and a multisensory oddball one, combining an audiovisual, an auditory and a visual stimulation stream, along with the corresponding deviances. Plasticity effects due to musical expertise were investigated by comparing the behavioral and MEG responses of musicians to non-musicians. The behavioral results indicated that the learning was successful for both musicians and non-musicians. The unimodal MEG responses are consistent with previous studies, revealing the contribution of Heschl's gyrus for the identification of auditory statistical mismatches and the contribution of medial temporal and visual association areas for the visual modality. The cortical network underlying audiovisual statistical learning was found to be partly common and partly distinct from the corresponding unimodal networks, comprising right temporal and left inferior frontal sources. Musicians showed enhanced activation in superior temporal and superior frontal gyrus. Connectivity and information processing flow amongst the sources comprising the cortical network of audiovisual statistical learning, as estimated by transfer entropy, was reorganized in musicians, indicating enhanced top-down processing. This neuroplastic effect showed a cross-modal stability between the auditory and audiovisual modalities.



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Nrf2 signaling and autophagy are complementary in protecting breast cancer cells during glucose deprivation

Publication date: Available online 9 April 2018
Source:Free Radical Biology and Medicine
Author(s): Alyssa Walker, Anju Singh, Ellen Tully, Juhyung Woo, Anne Le, Tu Nguyen, Shyam Biswal, Dipali Sharma, Edward Gabrielson
Autophagy can serve as a mechanism for survival of cells during nutrient deprivation by recycling cellular macromolecules and organelles transiently to provide essential metabolic substrates. However, autophagy itself causes metabolic stress to cells, and other cellular protective mechanisms likely cooperate with autophagy to promote cell survival during nutrient deprivation. In this study, we explored protective mechanisms in breast cancer cells in the setting of glucose deprivation. While breast cancer cells (MCF7 and T47D) survive in glucose-free medium for three days or more, autophagy is induced in this setting. Blocking autophagy pharmacologically with chloroquine or by knock-out of an essential autophagy gene, such as Beclin 1 or ATG7, markedly reduces the ability of cells to survive during glucose deprivation. Autophagy previously was shown to degrade p62, a protein that sequesters KEAP1, and KEAP1 in turn sequesters Nrf2, a master regulator of the antioxidant response. Hence, we investigated how the Nrf2 signaling pathway might be affected by glucose deprivation and autophagy. We found that while glucose deprivation does cause decreased cellular levels of p62, Nrf2 protein levels and activity unexpectedly increase in this setting. Moreover, this increase in Nrf2 activity provides important protection to breast cancer cells during glucose deprivation, since siRNA knockdown of Nrf2 markedly impairs survival during glucose deprivation. Antioxidants, N-acetyl cysteine and glutathione also protect these cells during glucose deprivation, leading us to conclude that Nrf2 signaling via its antioxidant activity has a critical and previously undescribed role of protecting cells during glucose deprivation-induced autophagy.

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Honokiol alleviates the degeneration of intervertebral disc via suppressing the activation of TXNIP-NLRP3 inflammasome signal pathway

Publication date: Available online 9 April 2018
Source:Free Radical Biology and Medicine
Author(s): Pan Tang, Jia-Ming Gu, Zi-Ang Xie, Yu Gu, Zhi-Wei Jie, Kang-Mao Huang, Ji-Ying Wang, Shun-Wu Fan, Xue-Sheng Jiang, Zhi-Jun Hu
Intervertebral disc degeneration (IVDD) is a multifactorial disease and responsible for many spine related disorders, causes disability in the workforce and heavy social costs all over the world. Honokiol, a low molecular weight natural product, could penetrate into and distribute in IVDs to achieve therapeutic effect in a rat tail model. Therefore, the present study was undertaken to examine the antiinflammatory, antioxidation and chondroprotective effect of honokiol using nucleus pulposus cells and investigate its mechanisms to provide a new basis for future clinical treatment of IVDD. In the current study, we demonstrated that honokiol inhibits the H2O2-induced apoptosis (caspase-9, caspase-3, and bax), levels of oxidative stress mediators (ROS, MDA), expression of inflammatory mediators (Interleukin-6, COX-2, and iNOS), major matrix degrading proteases (MMP-3, MMP-13, ADAMTS5, and ADAMTS4) associated with nucleus pulposus degradation. Furthermore, we found nucleus pulposus protective ability of honokiol by up-regulating extra cellular matrix anabolic factors like type II collagen (Col II) and SOX9 in nucleus pulposus. We also found that honokiol suppressed the phosphorylation of NF-kB and JNK, and activation of TXNIP-NLRP3 inflammasome in H2O2-stimulated nucleus pulposus cells, thereby inhibiting the activation of downstream inflammatory mediators such as Interleukin-1β. Furthermore, honokiol showed a cartilage protective effect in the progression of IVDD in a rat model induced by puncture. Thus, our results demonstrate that honokiol inhibited the H2O2 induced apoptosis, oxidative stress, and inflammatory responses through the depression of TXNIP/NLRP3/caspase-1/ Interleukin −1β signaling axis and the activation of NF-kB and JNK. Honokiol possess nucleus pulposus protective properties and may be of value in suppressing the pathogenesis of IVDD.

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Spatio-temporal monitoring of lipid peroxyl radicals in live cell studies combining fluorogenic antioxidants and fluorescence microscopy methods

Publication date: Available online 9 April 2018
Source:Free Radical Biology and Medicine
Author(s): Lana E. Greene, Richard Lincoln, Gonzalo Cosa
Lipid peroxidation of polyunsaturated fatty acids in cells may occur via their catalytic autoxidation through peroxyl radicals under oxidative stress conditions. Lipid peroxidation is related to a number of pathologies, and may be invoked in new forms of regulated cell death, yet it may also have beneficial roles in cell signaling cascades. Antioxidants are a natural line of defense against lipid peroxidation, and may accordingly impact the biological outcome associated with the redox chemistry of lipid peroxidation. Critical to unraveling the physiological and pathological role of lipid peroxidation is the development of novel probes with the partition, chemical sensitivity and more importantly, molecular specificity, enabling the spatial and temporal imaging of peroxyl radicals in the lipid membranes of live cells, reporting on the redox status of the cell membrane. This review describes our recent progress to visualize lipid peroxidation in model membrane systems and in live cell studies. Our work portrays the mechanistic insight leading to the development of a highly sensitive probe to monitor lipid peroxyl radicals (LOO). It also describes technical aspects including reagents and fluorescence microscopy methodologies to consider in order to achieve the much sought after monitoring of rates of lipid peroxyl radical production in live cell studies, be it under oxidative stress but also under cell homeostasis. This review seeks to bring attention to the study of lipid redox reactions and to lay the groundwork for the adoption of fluorogenic antioxidant probes and related fluorescence microscopy methods toward gaining rich spatiotemporal information on lipid peroxidation in live cells.

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High-speed 3D imaging of cellular activity in the brain using axially-extended beams and light sheets

Publication date: June 2018
Source:Current Opinion in Neurobiology, Volume 50
Author(s): Elizabeth MC Hillman, Venkatakaushik Voleti, Kripa Patel, Wenze Li, Hang Yu, Citlali Perez-Campos, Sam E Benezra, Randy M Bruno, Pubudu T Galwaduge
As optical reporters and modulators of cellular activity have become increasingly sophisticated, the amount that can be learned about the brain via high-speed cellular imaging has increased dramatically. However, despite fervent innovation, point-scanning microscopy is facing a fundamental limit in achievable 3D imaging speeds and fields of view. A range of alternative approaches are emerging, some of which are moving away from point-scanning to use axially-extended beams or sheets of light, for example swept confocally aligned planar excitation (SCAPE) microscopy. These methods are proving effective for high-speed volumetric imaging of the nervous system of small organisms such as Drosophila (fruit fly) and D. Rerio (Zebrafish), and are showing promise for imaging activity in the living mammalian brain using both single and two-photon excitation. This article describes these approaches and presents a simple model that demonstrates key advantages of axially-extended illumination over point-scanning strategies for high-speed volumetric imaging, including longer integration times per voxel, improved photon efficiency and reduced photodamage.

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Wound outcomes in negative pressure dressings (wound) study – a randomised trial in lower limb skin cancer

The incidence of skin cancer in New Zealand is one of the highest in the world.1 Surgical excision is the mainstay of treatment for these lesions. While excision and primary closure is desirable, wounds in the lower limb are often too large or complex to obtain direct apposition and split thickness skin grafting is used to achieve wound closure without tissue tension.2,3 Grafting in the lower limb carries a high risk of failure. Over the years, various methods have been employed to reduce the risk of graft failure.

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Decay of the Stress-Induced Ligand MICA Is Controlled by the Expression of an Alternative 3' Untranslated Region [INNATE IMMUNITY AND INFLAMMATION]

Recognition of the human stress-induced ligand MHC class I polypeptide-related sequence A (MICA) by the receptor NKG2D expressed on NK cells leads to NK cell–mediated killing of the target cells. Hence, the expression of MICA must be tightly regulated, and its cell surface expression needs to be quickly downregulated to avoid inappropriate activation of immune cells. In this article, we describe a transcript variant of human MICA that has not yet been studied, which contains a 3' untranslated region of 119 nt instead of 174. We identify its polyadenylation signal and demonstrate that, upon stresses, such as heat shock, butyrate treatment, and some oxidative and DNA-damaging treatments, the balance between the two MICA variants changes in favor of the less stable, longer variant. Mechanistically, we showed that this change is linked to microRNA activity and that poly-ADP ribose polymerase 1 is involved in the induction of the longer variant following stress. Thus, to our knowledge, we identify the first regulatory mechanism of a stress ligand's decay and also provide one of the first physiological examples for the biological function of a longer 3' untranslated region of a particular gene.



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