Splenomesenteric vein: formally recognising a clinically relevant section of the portal venous drainage system

Background and aims: The objective of this study was to identify and examine a common vein in the portal system that is not consistently named, and when named, to assess whether fundamental concepts were applied in the process of naming. Essentially, the portal venous system drains 3 regions of the gastrointestinal system into 3 major veins (superior mesenteric — SMV, splenic — SV, and inferior mesenteric — IMV) ultimately forming the portal vein (PV). TheSMV is formed from midgut veins generally representing the right side of the abdomen. The IMV is formed from hindgut veins generally representing the left side of the lower abdomen and pelvis, classically draining into the SV. The SV is formed from the foregut veins and generally accepts the IMV. The SV then joins the superior mesenteric vein to become the PV.Materials and methods: Sixty cadavers were dissected to observe the frequency of this morphology. Current anatomy and atlas texts were reviewed to identify the morphology and nomenclature.Results: Observations from this study identified a vein being formed from the convergence of the SV and IMV the author named “splenomesenteric vein”, which joins the superior mesenteric to form the PV.Conclusions: These findings suggest re-evaluating the morphology and nomenclature of this structure because of the pathology and clinical relevance of this area

Distal semimembranosus muscle-tendon-unit review: morphology, accurate terminology, and clinical relevance

Background: Our knowledge of the stability of the posteromedial knee is evolving. The distal semimembranosus is an important posteromedial stabilizer of the knee. Current anatomical texts and atlases do not accurately detail the distal insertion. Journal literature commonly mentions multiple distal insertions, one of which contributes to the oblique popliteal ligament. The purpose of this study was to review the literature, current morphology, terminology and clinical relevance of the distal semimembranosus muscle-tendon-unit (SMTU), and suggest alternative nomenclature. Methods: Literature search was conducted on anatomical and clinical texts, atlases, journals and websites to analyze the distal morphology of the semimembranosus muscle. Deep dissections were performed on 31 embalmed cadavers, 56 knees in total (27Rt and 29L), identifying the distal semimembranosus tendon morphology. Results: Literature search revealed significantly inconsistent morphology of the distal semimembranosus muscle-tendon-unit. Cadaver dissection revealed a consistent trifurcation with three dominant expansions. Cadaver dissection also revealed an oblique popliteal tendon/expansion, indigenous to SMTU, not a ligament. Conclusion: This study provides evidence of a consistent morphology and suggests a more precise nomenclature of the distal SMTU, which includes renaming the oblique popliteal ligament as the oblique popliteal tendon/expansion

Anatomical factors causing oedema of the lower limb during pregnancy

Background: The objective of this study was to investigate the morphology of the common iliac artery and vein (CIA&V) comparing right and left sides in females versus males. Pregnant women favour lying on one side at rest and during sleep. The reason for this may be due to the morphology and orientation between the CIA&V. Virtually all women during their pregnancy suffer from lower limb swelling. This study provides an anatomical explanation forthe propensity to lie consistently on one side, for lower limb swelling, and offers prevention measures.Materials and methods: A literature search was conducted on anatomical texts, atlases, journals, and websites regarding the morphology and orientation of the right and left CIA&V, lower limb oedema, and sleeping positions during pregnancy. Measurements from 15 dissected cadavers were conductedon the right and left CIA&V.Results: The literature search revealed very limited studies on the morphology and orientation of the right and left CIA&V with no studies relating this orientation to lower limb oedema or sleeping positions during pregnancy. Cadaver dissection revealed a relatively direct anterior to posterior orientation left CIA&Vand an oblique lateral to medial right CIA&V.Conclusions: This study suggests an explanation of why women lie on their left side when resting and sleeping during the third trimester due to the clinically relevant anatomy between the CIA&V

Harvesting of autogenous grafts for gingival recession coverage

The ultimate aim of periodontal plastic surgery is to create optimal pink esthetics through the reconstruction of gingival recessions. Application of autogenous soft tissue grafts is considered as a gold standard treatment modality with predictable esthetic outcomes for gingival recession coverage. Harvesting a free soft tissue graft from an esthetically irrelevant region of the oral mucosa using various techniques can prevent donor site complications around the adjacent teeth

Spatiotemporal parameters during turning gait maneuvers of different amplitudes in young and elderly healthy adults: A descriptive and comparative study.

Turning during walking adds complexity to gait and has been little investigated until now. Research question What are the differences in spatiotemporal parameters between young and elderly healthy adults performing quarter-turns (90°), half-turns (180°) and full-turns (360°)? The spatiotemporal parameters of 10 young and 10 elderly adults were recorded in a laboratory while turning at 90°, 180° and 360°. Two-way mixed ANOVA were performed to determine the effect of age and turning amplitude. Elderly were slower and needed more steps and time to perform turns of larger amplitude than young adults. Cadence did not differ across age or across turning amplitude. Generally, in the elderly, the spatial parameters were smaller and the temporal parameters enhancing stability (i.e., double-support phase and stance/cycle ratio) were larger, especially for turns of larger amplitudes. In elderly adults, the variability of some spatial parameters was decreased, whereas the variability of some temporal parameters was increased. Stride width of the external leg showed the most substantial difference between groups. Most parameters differed between turning at 90° and turning at larger amplitudes (180°, 360°). Significance This study extends the characterization of turning biomechanics with respect to ageing. It also suggested paying particular attention to the turning amplitude. Finally, the age-related differences may pave the way for new selective rehabilitation protocols in the elderly

Diabetes induced by gain-of-function mutations in the Kir6.1 subunit of the KATP channel

Gain-of-function (GOF) mutations in the pore-forming (Kir6.2) and regulatory (SUR1) subunits of K(ATP) channels have been identified as the most common cause of human neonatal diabetes mellitus. The critical effect of these mutations is confirmed in mice expressing Kir6.2-GOF mutations in pancreatic β cells. A second K(ATP) channel pore-forming subunit, Kir6.1, was originally cloned from the pancreas. Although the prominence of this subunit in the vascular system is well documented, a potential role in pancreatic β cells has not been considered. Here, we show that mice expressing Kir6.1-GOF mutations (Kir6.1[G343D] or Kir6.1[G343D,Q53R]) in pancreatic β cells (under rat-insulin-promoter [Rip] control) develop glucose intolerance and diabetes caused by reduced insulin secretion. We also generated transgenic mice in which a bacterial artificial chromosome (BAC) containing Kir6.1[G343D] is incorporated such that the transgene is only expressed in tissues where Kir6.1 is normally present. Strikingly, BAC-Kir6.1[G343D] mice also show impaired glucose tolerance, as well as reduced glucose- and sulfonylurea-dependent insulin secretion. However, the response to K(+) depolarization is intact in Kir6.1-GOF mice compared with control islets. The presence of native Kir6.1 transcripts was demonstrated in both human and wild-type mouse islets using quantitative real-time PCR. Together, these results implicate the incorporation of native Kir6.1 subunits into pancreatic K(ATP) channels and a contributory role for these subunits in the control of insulin secretion

Integrin-linked kinase is required for radial sorting of axons and Schwann cell remyelination in the peripheral nervous system

During development, Schwann cells (SCs) interpret different extracellular cues to regulate their migration, proliferation, and the remarkable morphological changes associated with the sorting, ensheathment, and myelination of axons. Although interactions between extracellular matrix proteins and integrins are critical to some of these processes, the downstream signaling pathways they control are still poorly understood. Integrin-linked kinase (ILK) is a focal adhesion protein that associates with multiple binding partners to link integrins to the actin cytoskeleton and is thought to participate in integrin and growth factor–mediated signaling. Using SC-specific gene ablation, we report essential functions for ILK in radial sorting of axon bundles and in remyelination in the peripheral nervous system. Our in vivo and in vitro experiments show that ILK negatively regulates Rho/Rho kinase signaling to promote SC process extension and to initiate radial sorting. ILK also facilitates axon remyelination, likely by promoting the activation of downstream molecules such as AKT/protein kinase B

The use of visual methods to explore how children construct and assign meaning to the ''self'' within two urban communities in the Western Cape, South Africa

This study aimed to explore how children construct and assign meaning to the ''self'' within two urban communities of Cape Town in South Africa. Using a child participation methodological framework data were collected using Photovoice and community maps with 54 participants between the ages of 9 and 12. Feelings of safety, social connectedness, and children's spaces were found to be central to the ways in which the participants constructed and assigned meaning to the ''self.'' The study provides implications for intervention programmes aimed at improving children's well-being to be inclusive of activities aimed at improving children's self-concept, including the construction of safe spaces for children to play, learn, and form meaningful relationships

Essential and distinct roles for cdc42 and rac1 in the regulation of Schwann cell biology during peripheral nervous system development

During peripheral nervous system (PNS) myelination, Schwann cells must interpret extracellular cues to sense their environment and regulate their intrinsic developmental program accordingly. The pathways and mechanisms involved in this process are only partially understood. We use tissue-specific conditional gene targeting to show that members of the Rho GTPases, cdc42 and rac1, have different and essential roles in axon sorting by Schwann cells. Our results indicate that although cdc42 is required for normal Schwann cell proliferation, rac1 regulates Schwann cell process extension and stabilization, allowing efficient radial sorting of axon bundles

Inhibition of 12/15-Lipoxygenase Protects Against β-Cell Oxidative Stress and Glycemic Deterioration in Mouse Models of Type 1 Diabetes

Islet β-cell dysfunction and aggressive macrophage activity are early features in the pathogenesis of type 1 diabetes (T1D). 12/15-Lipoxygenase (12/15-LOX) is induced in β-cells and macrophages during T1D and produces proinflammatory lipids and lipid peroxides that exacerbate β-cell dysfunction and macrophage activity. Inhibition of 12/15-LOX provides a potential therapeutic approach to prevent glycemic deterioration in T1D. Two inhibitors recently identified by our groups through screening efforts, ML127 and ML351, have been shown to selectively target 12/15-LOX with high potency. Only ML351 exhibited no apparent toxicity across a range of concentrations in mouse islets, and molecular modeling has suggested reduced promiscuity of ML351 compared with ML127. In mouse islets, incubation with ML351 improved glucose-stimulated insulin secretion in the presence of proinflammatory cytokines and triggered gene expression pathways responsive to oxidative stress and cell death. Consistent with a role for 12/15-LOX in promoting oxidative stress, its chemical inhibition reduced production of reactive oxygen species in both mouse and human islets in vitro. In a streptozotocin-induced model of T1D in mice, ML351 prevented the development of diabetes, with coincident enhancement of nuclear Nrf2 in islet cells, reduced β-cell oxidative stress, and preservation of β-cell mass. In the nonobese diabetic mouse model of T1D, administration of ML351 during the prediabetic phase prevented dysglycemia, reduced β-cell oxidative stress, and increased the proportion of anti-inflammatory macrophages in insulitis. The data provide the first evidence to date that small molecules that target 12/15-LOX can prevent progression of β-cell dysfunction and glycemic deterioration in models of T1D