Water-clear cell adenoma of the parathyroid gland: a rare entity

Water-clear cell hyperplasia is a rare but well-documented cause of primary hyperparathyroidism. Parathyroid adenomas of water-clear cell type are exceptionally rare, and only five case reports are available at present in the medical literature. We report an additional case of water-clear cell adenoma of the parathyroid gland, and the differential diagnoses are discussed.     

Triglycidylamine crosslinking of porcine aortic valve cusps or bovine pericardium results in improved biocompatibility, biomechanics, and calcification resistance: chemical and biological mechanisms

We investigated a novel polyepoxide crosslinker that was hypothesized to confer both material stabilization and calcification resistance when used to prepare bioprosthetic heart valves. Triglycidylamine (TGA) was synthesized via reacting epichlorhydrin and NH(3). TGA was used to crosslink porcine aortic cusps, bovine pericardium, and type I collagen. Control materials were crosslinked with glutaraldehyde (Glut). TGA-pretreated materials had shrink temperatures comparable to Glut fixation. However, TGA crosslinking conferred significantly greater collagenase resistance than Glut pretreatment, and significantly improved biomechanical compliance. Sheep aortic valve interstitial cells grown on TGA-pretreated collagen did not calcify, whereas sheep aortic valve interstitial cells grown on control substrates calcified extensively. Rat subdermal implants (porcine aortic cusps/bovine pericardium) pretreated with TGA demonstrated significantly less calcification than Glut pretreated implants. Investigations of extracellular matrix proteins associated with calcification, matrix metalloproteinases (MMPs) 2 and 9, tenascin-C, and osteopontin, revealed that MMP-9 and tenascin-C demonstrated reduced expression both in vitro and in vivo with TGA crosslinking compared to controls, whereas osteopontin and MMP-2 expression were not affected. TGA pretreatment of heterograft biomaterials results in improved stability compared to Glut, confers biomechanical properties superior to Glut crosslinking, and demonstrates significant calcification resistance.     

Heterogeneity in synaptic transmission along a Drosophila larval motor axon

At the Drosophila melanogaster larval neuromuscular junction (NMJ), a motor neuron releases glutamate from 30-100 boutons onto the muscle it innervates. How transmission strength is distributed among the boutons of the NMJ is unknown. To address this, we created synapcam, a version of the Ca2+ reporter Cameleon. Synapcam localizes to the postsynaptic terminal and selectively reports Ca2+ influx through glutamate receptors (GluRs) with single-impulse and single-bouton resolution. GluR-based Ca2+ signals were uniform within a given connection (that is, a given bouton/postsynaptic terminal pair) but differed considerably among connections of an NMJ. A steep gradient of transmission strength was observed along axonal branches, from weak proximal connections to strong distal ones. Presynaptic imaging showed a matching axonal gradient, with higher Ca2+ influx and exocytosis at distal boutons. The results suggest that transmission strength is mainly determined presynaptically at the level of individual boutons, possibly by one or more factors existing in a gradient.     

Mortality trends in falciparum malaria--effect of gender difference and pregnancy

Falciparum malaria in pregnancy is a significant health problem in India. Pregnant women constitute an important high risk group for malaria infection which may cause abortions, stillbirths, intra-uterine growth retardation (IUGR) and premature labour. In this hospital based study on 602 admitted patients of falciparum malaria which included 314 males, 243 non-pregnant females and 45 pregnant females, there was significantly increased mortality rate in females (18.4%) in comparison to males (7.64%, p < 0.001). The mortality rate was highly significant in pregnant females (37.77%) in comparison to non-pregnant females (14.81%) and males (7.64%; p < 0.001). Severe anaemia with Hb < 5 gm% was observed more commonly in pregnant patients (20.0%) in comparison to non-pregnant patients (4.11%). Incidence of malaria infection was more in primi gravida and second gravida. Pregnancy related complications in the form of preterm live births, intra-uterine death (IUD), still births and abortions were more in primi parous than multiparous patients. As the pregnancy is associated with increased incidence and adverse outcome of P.falciparum malaria infection, chemoprophylaxis should be made an integral part of antenatal care along with antianaemia therapy to reduce the risk of serious maternal and fetal complications.     

Vascularization and tissue infiltration of a biodegradable polyurethane matrix

Urethanes are frequently used in biomedical applications because of their excellent biocompatibility. However, their use has been limited to bioresistant polyurethanes. The aim of this study was to develop a nontoxic biodegradable polyurethane and to test its potential for tissue compatibility. A matrix was synthesized with pentane diisocyanate (PDI) as a hard segment and sucrose as a hydroxyl group donor to obtain a microtextured spongy urethane matrix. The matrix was biodegradable in an aqueous solution at 37 degrees C in vitro as well as in vivo. The polymer was mechanically stable at body temperatures and exhibited a glass transition temperature (Tg) of 67 degrees C. The porosity of the polymer network was between 10 and 2000 microm, with the majority of pores between 100 and 300 microm in diameter. This porosity was found to be adequate to support the adherence and proliferation of bone-marrow stromal cells (BMSC) and chondrocytes in vitro. The degradation products of the polymer were nontoxic to cells in vitro. Subdermal implants of the PDI-sucrose matrix did not exhibit toxicity in vivo and did not induce an acute inflammatory response in the host. However, some foreign-body giant cells did accumulate around the polymer and in its pores, suggesting its degradation is facilitated by hydrolysis as well as by giant cells. More important, subdermal implants of the polymer allowed marked infiltration of vascular and connective tissue, suggesting the free flow of fluids and nutrients in the implants. Because of the flexibility of the mechanical strength that can be obtained in urethanes and because of the ease with which a porous microtexture can be achieved, this matrix may be useful in many tissue-engineering applications.     

Round worm migration along ventriculoperitoneal shunt tract: a rare complication

Though a ventriculoperitoneal shunt has been associated with myriads of unusual complications, so has been that with roundworms. A case of a three-year-old boy is presented who had an unusual complication of roundworm migration along the shunt tract that presented as shunt tract infection.