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Population and conservation genetics studies have greatly benefited from the development of new techniques and bioinformatic tools associated with next-generation sequencing. Analysis of extensive data sets from whole-genome sequencing of even a few individuals allows the detection of patterns of fine-scale population structure and detailed reconstruction of demographic dynamics through time. In this study, we investigated the population structure, genomic diversity and demographic history of the Komodo dragon (Varanus komodoensis), the world's largest lizard, by sequencing the whole genomes of 24 individuals from the five main Indonesian islands comprising the entire range of the species. Three main genomic groups were observed. The populations of the Island of Komodo and the northern coast of Flores, in particular, were identified as two distinct conservation units. Degrees of genomic divergence among island populations were interpreted as a result of changes in sea level affecting connectivity across islands. Demographic inference suggested that Komodo dragons probably experienced a relatively steep population decline over the last million years, reaching a relatively stable N e during the Saalian glacial cycle (400-150 thousand years ago) followed by a rapid N e decrease. Genomic diversity of Komodo dragons was similar to that found in endangered or already extinct reptile species. Overall, this study provides an example of how whole-genome analysis of a few individuals per population can help define population structure and intraspecific demographic dynamics. This is particularly important when applying population genomics data to conservation of rare or elusive endangered species., (© 2021 The Authors. Molecular Ecology published by John Wiley & Sons Ltd.)

Background: The tissue regeneration process requires high oxygen and energy levels. Cytoglobin (Cygb) is a member of the globin family, which has the ability to bind oxygen, plays a role in dealing with oxidative stress, and carries oxygen into the mitochondria. Energy production for tissue regeneration is associated with mitochondria-especially mitochondrial biogenesis. The peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1alpha protein helps to regulate mitochondrial biogenesis. House geckos (Hemidactylus platyurus) are reptiles that have the ability to regenerate the tissue in their tails. House geckos were selected as the animal models for this study in order to analyze the association of Cygb with oxygen supply and the association of PGC-1α with energy production for tissue regeneration., Results: The growth of house gecko tails showed a slow growth at the wound healing phase, then followed by a fast growth after wound healing phase of the regeneration process. While Cygb mRNA expression reached its peak at the wound healing phase and slowly decreased until the end of the observation. PGC-1α mRNA was expressed and reached its peak earlier than Cygb., Conclusions: The expressions of both the Cygb and PGC-1α genes were relatively high compared to the control group. We therefore suggest that Cygb and PGC-1α play an important role during the tissue regeneration process.

The house gecko ( Hemidactylus platyurus ) has evolved the ability to autotomize its tail when threatened. The lost part is then regrown via epimorphic regeneration in a process that requires high energy and oxygen levels. Oxygen demand is therefore likely to outstrip supply and this can result in relative hypoxia in the tissues of the regenerating tail. The hypoxic state is stabilized by the Hypoxia Inducible Factor-1α (HIF-1α) and HIF-2α proteins. We induced tail autotomy in 30 mal H. platyurus adults using a standard procedure and then collected samples of the regenerated tail tissue on days 1, 3, 5, 8, 10, 13, 17, 21, 25, and 30 post autotomy. For each sample, mRNA expression was analyzed by qPCR, proteins were analyzed using Western Blot tests and immunohistochemistry, and the histological structure was analyzed using Hematoxylin and Eosin staining. On day 1, HIF-1α mRNA expression increased and the tissue was dominated by leucocyte and erythrocyte cells. HIF-1α mRNA expression peaked on day 3, at which time some cells were actively proliferating, migrating, and differentiating. At the same time as HIF-1α expression decreased, HIF-2α mRNA expression increased, as did overall cellular activity. HIF-2α expression increased more gradually but was present over a longer period of time than HIF-1α. We hypothesize that HIF-1α helps to initially stimulate the tissue regeneration process while HIF-2α functionally takes over the role of HIF-1α after HIF-1α succumbs to the oxygen conditions, but we suspect that both HIF-1α and HIF-2α play a role in overcoming the tissue's hypoxic state.

Laparoscopic sleeve gastrectomy (LSG) is gaining popularity as bariatric surgery, a small percentage of subjects regain weight after surgery. This study was designed to evaluate body weight changes over a period of two years after LSG and investigate the role of serotonin in regulating energy balance. This is a prospective cohort study. A total of 92 patients with morbid obesity (64 women and 28 men) underwent LSG. All the participants were subjected to physical examination and detailed medical history. Anthropometric measurements were accomplished pre-operative and post-operatively at a frequency of four times per year for two years follow-up. Laboratory investigations were performed pre-operatively, and one and two years post-operatively. Blood samples were collected in the fasting state; for glucose, lipid profile and hormonal assays. Hormones measured were plasma insulin, leptin, serotonin and ghrelin. Results revealed that 35.7% weight loss occurred after one year. However, there was variability in the individual weight loss curve during the period between the first and second post-operative years. Thus, patients were divided into two groups: group I included 78 patients (84%) who maintained the lost weight, and group II included 14 patients (16.0%) who regained weight within 24 months post-operatively. Correlation with BMI revealed positive correlation with leptin and serotonin, whilst negative correlation with ghrelin in group II patients. Mechanisms of weight loss after LSG are not only attributable to gastric restriction but also to the neurohormonal changes. In addition, serotonin may possibly contribute to the interplay of regulatory systems of energy homeostasis.

Background: Ultrasound has growing applications in airway management during anesthesia. The aim of the present study was to evaluate the feasibility of real-time ultrasound-guided tracheal intubation in patients with cervical spine immobilization relative to fiberscope-guided tracheal intubation., Patients and Methods: This randomized controlled study was carried out on 266 adult patients who have a rigid neck collar in place for cervical spine immobilization and were randomly allocated into two equal groups. All patients were subjected to the same anesthetic protocol. After full neuromuscular blockade, neck collar was removed and tracheal intubation was done in the neutral position. In group A, the trachea was intubated guided by a 5-12-MHz linear ultrasound probe attached to a Sonoscape A5 ultrasound machine. In group B, the trachea was intubated by an endotracheal tube mounted over a fiberscope (Karl Storz, working length 65 cm, distal tip diameter 5.6 mm). Hemodynamic measurements and oxygen saturation were recorded. Tracheal intubation criteria for both groups including duration of the intubation procedure, number of intubation attempts, success rate at each attempt, and the lowest oxygen saturation recorded during tracheal intubation were recorded., Results: Ultrasound and fiberscope achieved comparable time for tracheal intubation (57 ± 12 vs. 55 ± 10 s), respectively. Success rate of tracheal intubation at the first attempt was higher in the fiberscope group than the ultrasound group, with a P value of 0.032. The overall success rate was not significantly different between the two groups., Conclusions: Ultrasound-guided tracheal intubation showed a lower first attempt success rate in patients with cervical spine immobilization compared to fiberscope-guided tracheal intubation but the overall success rates were comparable. Ultrasound can be an alternative technique for guiding tracheal intubation in patients with cervical spine immobilization., Registry Number: PACTR201602001476292.

Background: In Egypt, the prevalence of chronic hepatitis C (CHC) infection is 13.8% of whole population and about 80% of the patients with hepatocellular carcinoma have underling hepatitis C., Aim: This study was designed to assess the diagnostic value of plasma miR-122 and miR-21 in patients with CHC, genotype-4, to detect fibrosis progression versus noninvasive indices and their diagnostic value in detection of early stages of hepatocellular carcinoma (HCC)., Methodology: A prospective study that included 180 patients, divided into 3 groups: healthy controls (group I), CHC patients (group II), and hepatitis C patients with HCC (group III); all cases were subjected to thorough clinical, radiological, and laboratory investigations. Selected biomarkers were evaluated and correlated with degree of liver damage. Results revealed that miR-122 followed by miR-21 had the highest efficiency in prediction of liver cell damage. Also, miR-21 was strongly correlated with vascular endothelial growth factor (VEGF) and alpha fetoprotein ( α -FP) in HCC patients., Conclusions: Plasma miR-122 and miR-21 had strong correlation with degree fibrosis in HCV genotype-4 patients; consequently they can be considered as potential biomarker for early detection of hepatic fibrosis. Moreover, miR-21 can be used as a potential biomarker, for early detection of HCC combined with VEGF and α -FP.