Lahar inundated, modified, and preserved 1.88 Ma early hominin (OH24 and OH56) Olduvai DK site

Publication date: March 2018
Source:Journal of Human Evolution, Volume 116
Author(s): I.G. Stanistreet, H. Stollhofen, J.K. Njau, P. Farrugia, M.C. Pante, F.T. Masao, R.M. Albert, M.K. Bamford
Archaeological excavations at the DK site in the eastern Olduvai Basin, Tanzania, age-bracketed between ∼1.88 Ma (Bed I Basalt) and ∼1.85 Ma (Tuff IB), record the oldest lahar inundation, modification, and preservation of a hominin "occupation" site yet identified. Our landscape approach reconstructs environments and processes at high resolution to explain the distribution and final preservation of archaeological materials at the DK site, where an early hominin (likely Homo habilis) assemblage of stone tools and bones, found close to hominin specimens OH24 and OH56, developed on an uneven heterogeneous surface that was rapidly inundated by a lahar and buried to a depth of 0.4–1.2 m (originally ∼1.0–2.4 m pre-compaction). The incoming intermediate to high viscosity mudflow selectively modified the original accumulation of "occupation debris," so that it is no longer confined to the original surface. A dispersive debris "halo" was identified within the lahar deposit: debris is densest immediately above the site, but tails off until not present >150 m laterally. Voorhies indices and metrics derived from limb bones are used to define this dispersive halo spatially and might indicate a possible second assemblage to the east that is now eroded away. Based upon our new data and prior descriptions, two possibilities for the OH24 skull are suggested: it was either entrained by the mudflow from the DK surface and floated due to lower density toward its top, or it was deposited upon the solid top surface after its consolidation. Matrix adhering to material found in association with the parietals indicates that OH56 at least was relocated by the mudflow.



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Notching a New Pathway in Vascular Flow Sensing

Publication date: Available online 2 January 2018
Source:Trends in Cell Biology
Author(s): Anne K. Lagendijk, Alpha S. Yap, Benjamin M. Hogan
Vascular barrier function is controlled at cell–cell junctions in response to blood flow, but how vascular endothelial cells sense and respond to flow remains to be understood. A recent study describes a flow-sensing pathway involving non-canonical Notch and cadherin signaling that sheds new light on mechanisms controlling the endothelial barrier.



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LIVER CARBOHYDRATES METABOLISM: A NEW ISLET-NEOGENESIS ASSOCIATED PROTEIN PEPTIDE (INGAP-PP) TARGET

Publication date: Available online 3 January 2018
Source:Peptides
Author(s): Hernán Gonzalo Villagarcía, Carolina Lisi Román, María Cecilia Castro, Luisa Arbeláez González, María Teresa Ronco, Daniel Eleazar Francés, María Laura Massa, Bárbara Maiztegui, Luis Emilio Flores, Juan José Gagliardino, Flavio Francini
Islet-Neogenesis Associated Protein-Pentadecapeptide (INGAP-PP) increases β-cell mass and enhances glucose and amino acids-induced insulin secretion. Our aim was to demonstrate its effect on liver metabolism. For that purpose, adult male Wistar rats were injected twice-daily (10 days) with saline solution or INGAP-PP (250 μg). Thereafter, serum glucose, triglyceride and insulin levels were measured and homeostasis model assessment (HOMA-IR) and hepatic insulin sensitivity (HIS) were determined. Liver glucokinase and glucose-6-phosphatase (G-6-Pase) expression and activity, phosphoenolpyruvate carboxykinase (PEPCK) expression, phosphofructokinase-2 (PFK-2) protein content, P-Akt/Akt and glycogen synthase kinase-3β (P-GSK3/GSK3) protein ratios and glycogen deposit were also determined. Additionally, glucokinase activity and G-6-Pase and PEPCK gene expression were also determined in isolated hepatocytes from normal rats incubated with INGAP-PP (5 μg/ml).INGAP-PP administration did not modify any of the serum parameters tested but significantly increased activity of liver glucokinase and the protein level of its cytosolic activator, PFK-2. Conversely, INGAP-PP treated rats decreased gene expression and enzyme activity of gluconeogenic enzymes, G-6-Pase and PEPCK. They also showed a higher glycogen deposit and P-GSK3/GSK3 and P-Akt/Akt ratio. In isolated hepatocytes, INGAP-PP increased GK activity and decreased G-6-Pase and PEPCK expression.These results demonstrate a direct effect of INGAP-PP on the liver acting through P-Akt signaling pathway. INGAP-PP enhances liver glucose metabolism and deposit and reduces its production/output, thereby contributing to maintain normal glucose homeostasis. These results reinforce the concept that INGAP-PP might become a useful tool to treat people with impaired islet/liver glucose metabolism as it occurs in T2D.



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Enhanced angiotensin II induced sodium appetite in renovascular hypertensive rats

Publication date: Available online 3 January 2018
Source:Peptides
Author(s): Camila F. Roncari, Rafaela M. Barbosa, Regina C. Vendramini, Laurival A. De Luca, José V. Menani, Eduardo Colombari, Débora S.A. Colombari
Renovascular hypertensive 2-kidney, 1-clip (2K1C) rats have an increased activity of the renin-angiotensin system and an initial transitory increase in daily water and NaCl intake. However, the dipsogenic and natriorexigenic responses to angiotensin II (ANG II) have not been tested yet in 2K1C rats. Therefore, in the present study, we evaluated water and 0.3 M NaCl intake induced by water deprivation (WD)-partial rehydration (PR) or intracerebroventricular (icv) ANG II in 2K1C rats. In addition, the cardiovascular changes to these treatments were also evaluated. Male Holtzman rats received a silver clip around the left renal artery to induce 2K1C renovascular hypertension. In the 5th week, a group of animals received a guide cannula in the lateral ventricle for icv injections. Daily water intake increased from the 3rd week after surgery and remained elevated until the 6th week (last recording week), whereas daily 0.3 M NaCl intake transiently increased from the 2nd to the 5th week after surgery. On the 6th week, in spite of comparable daily 0.3 M NaCl intake between 2K1C and sham rats, WD-PR and icv ANG II induced an increased 0.3 M NaCl intake in 2K1C rats. Water intake induced by WD-PR, not by icv ANG II, also increased in 2K1C rats. The increase in arterial pressure to WD-PR or icv ANG II was similar in sham and 2K1C rats. Therefore, these results suggest that 2K1C rats are more responsive to the natriorexigenic effects of ANG II, whereas other responses to ANG II are not modified.



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First Aid for Skin Tears by Mini Patch Grafting from the Flap Edge

Publication date: Available online 3 January 2018
Source:The Journal of Emergency Medicine
Author(s): Isamu Ikeda, Toshikatsu Igata, Hironobu Ihn
BackgroundTraumatic skin tears often occur in patients with dystrophic skin. Closing them with adhesive skin closures is useful for patients with a healthy flap, but occasionally fails to cover the entire defect. We describe a simple technique to perform mini patch grafting on the remaining raw surface without damaging healthy skin.DiscussionThe skin flap is spread out and fixed with adhesive skin strips to minimize defects first. Small pieces of skin are obtained by trimming the edges of the skin flap with curved tip scissors. They are placed on the defect with free spaces of 3 to 5 mm between each of the grafts. Then the whole wound is covered with a dressing and gauze pads. Healing of the ulcer could be markedly promoted with little enlargement of the skin defect.ConclusionsSmall pieces of skin trimmed out from the edge of skin flap can be used as a mini patch graft that remarkably enhances healing of remaining open surface.



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Recipient Selection for Optimal Utilization of Discarded Grafts in Liver Transplantation

AbstractBackgroundIn France, liver grafts that have been refused by at least 5 teams are considered for rescue allocation, with the choice of the recipient being at the team's discretion. While this system permits the use of otherwise discarded grafts in a context of organ shortage, outcomes and potential benefits need to be assessed.MethodsBetween 2011 and 2015, outcomes of rescue allocation grafts (n=33) were compared to standard allocation grafts (n=321) at a single French center.ResultsLiver grafts in the rescue allocation group were older (63+/-17 vs. 54+/-18y, p=0.007) and had a higher donor risk index (1.86+/-0.45 vs. 1.61+/-0.47, p=0.010). Recipients in this group had a lower MELD score (14+/-5 vs. 22+/-10, p

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The Meaning of Being a Living Kidney, Liver or Stem Cell Donor - A Meta-Ethnography

ABSTRACTBackgroundStudies on living donors from the donors' perspective show that the donation process involves both positive and negative feelings involving vulnerability. Qualitative studies of living kidney, liver, and allogeneic hematopoietic stem cell donors have not previously been merged in the same analysis. Therefore, our aim was to synthesize current knowledge of these donors' experiences in order to deepen understanding of the meaning of being a living donor for the purpose of saving or extending someone's life.MethodsThe meta-ethnography steps presented by Noblit & Hare in 1988 were used.ResultsForty-one qualitative studies from 1968 to 2016 that fulfilled the inclusion criteria were analyzed. The studies comprised experiences of over 670 donors. The time since donation varied from 2 days to 29 years. A majority of the studies, 25 out of 41, were on living kidney donors. The synthesis revealed that the essential meaning of being a donor is doing what one feels one has to do, involving 6 themes; A sense of responsibility, Loneliness and abandonment, Suffering, Pride and gratitude, A sense of togetherness, and A life changing event.ConclusionThe main issue is that one donates irrespective of what one donates. The relationship to the recipient determines the motives for donation. The deeper insight into the donors' experiences provides implications for their psychological care. Background Studies on living donors from the donors' perspective show that the donation process involves both positive and negative feelings involving vulnerability. Qualitative studies of living kidney, liver, and allogeneic hematopoietic stem cell donors have not previously been merged in the same analysis. Therefore, our aim was to synthesize current knowledge of these donors' experiences in order to deepen understanding of the meaning of being a living donor for the purpose of saving or extending someone's life. Methods The meta-ethnography steps presented by Noblit & Hare in 1988 were used. Results Forty-one qualitative studies from 1968 to 2016 that fulfilled the inclusion criteria were analyzed. The studies comprised experiences of over 670 donors. The time since donation varied from 2 days to 29 years. A majority of the studies, 25 out of 41, were on living kidney donors. The synthesis revealed that the essential meaning of being a donor is doing what one feels one has to do, involving 6 themes; A sense of responsibility, Loneliness and abandonment, Suffering, Pride and gratitude, A sense of togetherness, and A life changing event. Conclusion The main issue is that one donates irrespective of what one donates. The relationship to the recipient determines the motives for donation. The deeper insight into the donors' experiences provides implications for their psychological care. Corresponding author: Annika M Kisch, Department of Haematology, Skåne University Hospital, S-221 85 Lund, Sweden, annika.m.kisch@skane.se AUTHORSHIP PAGE - Authorship statement Annika M Kisch, Anna Forsberg, Isabell Fridh, and Annette Lennerling were responsible for the research design. Annika M Kisch, Anna Forsberg, Isabell Fridh, and Annette Lennerling wrote the paper. Matilda Almgren, Martina Lundmark, Charlotte Lovén, Anne Flodén, Madeleine Nilsson, and Veronika Karlsson contributed with comments to the draft manuscript. All authors: Annika M Kisch, Anna Forsberg, Isabell Fridh, Matilda Almgren, Martina Lundmark, Charlotte Lovén, Anne Flodén, Madeleine Nilsson, Veronika Karlsson, and Annette Lennerling participated in conducting the research and data analysis. Annika M Kisch, Anna Forsberg, Isabell Fridh, and Annette Lennerling were primarily responsible for the synthesis. The authors declare no conflicts of interest. Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.

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