How do embryonic turtles process yolk? Evidence from the Snapping Turtle, Chelydra serpentina (Chelydridae)

In this study, we used scanning electron microscopy to determine which of these developmental patterns (if either) occurs in a representative chelonian, the North American Snapping Turtle (Chelydra serpentina (Linnaeus, 1758)). Our observations reveal that yolk-filled endodermal cells progressively fill the yolk sac cavity. These cells become organized around anastomosing blood vessels, forming elongated strands that are morphologically well suited for yolk digestion and vascular transport of nutrients. This developmental pattern shares features with that of squamates, but it differs markedly from that of birds. These observations indicate that mechanisms of yolk processing in lizards and snakes have an evolutionary history that pre-dates the squamate clade.
Source: Canadian Journal of Zoology - Category: Zoology Authors: Source Type: research

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CONCLUSIONS: Despite differences in adiposity and total BAT volume, we found that healthy, lean, young women and men do not differ in the relative amount, glucose uptake, and distribution of BAT. Dorsocervical 18 F-fluorodeoxyglucose uptake was more prevalent in women and may be a remnant of interscapular BAT seen in human newborns. Future studies are needed to discern how BAT contributes to whole-body thermal physiology and body weight regulation in women and men. PMID: 31970907 [PubMed - in process]
Source: Obesity - Category: Eating Disorders & Weight Management Authors: Tags: Obesity (Silver Spring) Source Type: research
AbstractPurposeTo compare CT angiography (CTA) and tagged red blood cell (RBC) scan as a function of time from these initial imaging studies to subsequent conventional angiography and catheter-directed embolization in patients with gastrointestinal (GI) bleeding.MethodsAn IRB-approved retrospective study was conducted of 35 consecutive patients diagnosed with GI bleeding that received angiography for planned catheter-directed embolization. Of these patients, 20 were diagnosed with bleeding using a tagged RBC scan, whereas 15 were diagnosed using CTA. The lengths of time between diagnostic study order to study completion, d...
Source: Abdominal Imaging - Category: Radiology Source Type: research
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Source: Scandinavian Journal of Primary Health Care - Category: Primary Care Authors: Source Type: research
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Source: Scandinavian Journal of Primary Health Care - Category: Primary Care Authors: Source Type: research
Objectives: To evaluate radiological fracture reduction and clinical results using the pararectus approach in complex acetabular fractures involving the anterior column. Design: Retrospective database analysis of prospectively collected data. Setting: Level 1 trauma center. Patients/Participants: 61 patients (48 male and 13 female) with a median age of 55 (range 17–91) years were included. According to the chosen surgical approach, they were divided into 2 groups. The P-group included 43 patients, among them 32 male and 11 female patients with a median age of 55 (range 17–90) years. Eighteen patients...
Source: Journal of Orthopaedic Trauma - Category: Orthopaedics Tags: Original Article Source Type: research
Objective: To document angles, from 2 difference starting points, or danger zones that should be avoided to minimize risk of injury or irritation to the saphenous neurovascular bundle (SNVB) during suture button (SB) fixation for distal tibiofibular syndesmosis injuries. Design: Retrospective imaging study. Setting: Academic Level 1 trauma center. Patients: Forty-eight randomly selected patients with healthy ankles and computed tomography scans for nonankle diagnoses. Main Outcome Measures: Computed tomography scans and 3D reconstructed images were used to define the angle between the SNVB and 2 different fib...
Source: Journal of Orthopaedic Trauma - Category: Orthopaedics Tags: Original Article Source Type: research
The risk of extra-colonic cancer in IBD is unclear. While thiopurines and tumour necrosis factor- α antagonists (anti-TNFs) are associated with increased risk of skin cancer and lymphoma in IBD, there is scant data on breast cancer in IBD. We evaluated the prevalence of breast cancer in IBD and investigated the role of biologics, immunomodulators, and clinical characteristics of IBD in patients with IBD and breast cancer.
Source: Gastroenterology - Category: Gastroenterology Authors: Tags: Epidemiology Source Type: research
Publication date: Available online 23 January 2020Source: Nano EnergyAuthor(s): Mingzi Sun, Bolong HuangAbstractPursuing the precise structural identification of functional two-dimensional (2D) layered metal chalcogenides (LMCs) are key factors dominating the origins of the unique electronic and ferroelectric properties. However, the complicated phase change of In2Se3 and their high sensitivity towards the intrinsic defects still require the advanced technology to identify the origins of the inhomogeneous charge distribution induced in-plane and out-of-plane ferroelectricity. Herein, we have presented comprehensive theoret...
Source: Nano Energy - Category: Nanotechnology Source Type: research
Publication date: Available online 23 January 2020Source: Materials Today: ProceedingsAuthor(s): Polina G. Bespalova, Alexandr A. Vorobyev, Tatyana S. Kunkel, Alexandr L. Shakhmin, Maxim V. MishinAbstractThis work dedicated the study of iron oxide deposition by metalorganic chemical vapour deposition (MOCVD) in hot-walls reactor with Fe(CO)5 in Ar-O2 atmosphere under pressure about 70 Pa. Phase and structure studied by x-ray photoelectron spectroscopy (XPS) and reflection high-energy electron diffraction(RHEED). This analysis also gives information for some common factors of MOCVD decomposition of Fe(CO)5. Topology of th...
Source: Materials Today: Proceedings - Category: Materials Science Source Type: research
Publication date: Available online 23 January 2020Source: Materials Today: ProceedingsAuthor(s): Robert Kosturek, Lucjan Śnieżek, Janusz Torzewski, Marcin WachowskiAbstractThe aim of this research was to investigate the microstructure and fatigue properties of AA2519-O joint obtained in the friction stir welding process. The microstructure of the joint has been analyzed with the use of a light electron microscope and compared with the results of microhardness analysis. Fatigue properties were established in low-cycle fatigue tests with constant true strain amplitude equal to ε = 0.25%. The obtained amplitudes...
Source: Materials Today: Proceedings - Category: Materials Science Source Type: research
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