Study on Magnesium based Pyrotechnic Composition as a Priming Charge

A new pyrotechnic composition containing Mg/KNO3/phenolic resin has been formulated and studied in detail for its sensitivity, mechanical and thermal properties, moisture and environmental effects and performance in a closed vessel. The data generated reveal that this composition shows superior performance, better mechanical properties and less susceptibility to moisture as compared to gunpowder. In addition, performance of the composition under extreme hot (45 degree centigrade) and cold (-26 degree centigrade) environmental conditions is not affected at all. Differential thermal analyser results indicate that phenolic resin plays a vital role in reducing the ignition temperature of Mg/KNO/sub 3/ system

S110, a novel decitabine dinucleotide, increases fetal hemoglobin levels in baboons (P. anubis)

<p>Abstract</p> <p>Background</p> <p>S110 is a novel dinucleoside analog that could have advantages over existing DNA methyltransferase (DNMT) inhibitors such as decitabine. A potential therapeutic role for S110 is to increase fetal hemoglobin (HbF) levels to treat β-hemoglobinopathies. In these experiments the effect of S110 on HbF levels in baboons and its ability to reduce DNA methylation of the γ-globin gene promoter in vivo were evaluated.</p> <p>Methods</p> <p>The effect of S110 on HbF and γ-globin promoter DNA methylation was examined in cultured human erythroid progenitors and in vivo in the baboon pre-clinical model. S110 pharmacokinetics was also examined in the baboon model.</p> <p>Results</p> <p>S110 increased HbF and reduced DNA methylation of the γ-globin promoter in human erythroid progenitors and in baboons when administered subcutaneously. Pharmacokinetic analysis was consistent with rapid conversion of S110 into the deoxycytosine analog decitabine that binds and depletes DNA.</p> <p>Conclusion</p> <p>S110 is rapidly converted into decitabine, hypomethylates DNA, and induces HbF in cultured human erythroid progenitors and the baboon pre-clinical model.</p

Cardiogenesis with a focus on vasculogenesis and angiogenesis

The initial intraembryonic vasculogenesis occurs in the cardiogenic mesoderm. Here, a cell population of proendocardial cells detaches from the mesoderm that subsequently generates the single endocardial tube by forming vascular plexuses. In the course of embryogenesis, the endocardium retains vasculogenic, angiogenic and haematopoietic potential. The coronary blood vessels that sustain the rapidly expanding myocardium develop in the course of the formation of the cardiac loop by vasculogenesis and angiogenesis from progenitor cells of the proepicardial serosa at the venous pole of the heart as well as from the endocardium and endothelial cells of the sinus venosus. Prospective coronary endothelial cells and progenitor cells of the coronary blood vessel walls (smooth muscle cells, perivascular cells) originate from different cell populations that are in close spatial as well as regulatory connection with each other. Vasculo‐ and angiogenesis of the coronary blood vessels are for a large part regulated by the epicardium and epicardium‐derived cells. Vasculogenic and angiogenic signalling pathways include the vascular endothelial growth factors, the angiopoietins and the fibroblast growth factors and their receptors

A strategy to discover new organizers identifies a putative heart organizer

Organizers are regions of the embryo that can both induce new fates and impart pattern on other regions. So far, surprisingly few organizers have been discovered, considering the number of patterned tissue types generated during development. This may be because their discovery has relied on transplantation and ablation experiments. Here we describe a new approach, using chick embryos, to discover organizers based on a common gene expression signature, and use it to uncover the anterior intestinal portal (AIP) endoderm as a putative heart organizer. We show that the AIP can induce cardiac identity from non-cardiac mesoderm and that it can pattern this by specifying ventricular and suppressing atrial regional identity. We also uncover some of the signals responsible. The method holds promise as a tool to discover other novel organizers acting during development

Biliary atresia

Biliary atresia (BA) is a rare disease characterised by a biliary obstruction of unknown origin that presents in the neonatal period. It is the most frequent surgical cause of cholestatic jaundice in this age group. BA occurs in approximately 1/18,000 live births in Western Europe. In the world, the reported incidence varies from 5/100,000 to 32/100,000 live births, and is highest in Asia and the Pacific region. Females are affected slightly more often than males. The common histopathological picture is one of inflammatory damage to the intra- and extrahepatic bile ducts with sclerosis and narrowing or even obliteration of the biliary tree. Untreated, this condition leads to cirrhosis and death within the first years of life. BA is not known to be a hereditary condition. No primary medical treatment is relevant for the management of BA. Once BA suspected, surgical intervention (Kasai portoenterostomy) should be performed as soon as possible as operations performed early in life is more likely to be successful. Liver transplantation may be needed later if the Kasai operation fails to restore the biliary flow or if cirrhotic complications occur. At present, approximately 90% of BA patients survive and the majority have normal quality of life

Posterior midline cervical fetal cystic hygroma.

Posterior midline cervical cystic hygromas (PMC) are frequently found associated with chromosomal aberrations and usually do not survive. The present report illustrates diagnosis of this condition by sonography in an 18 weeks old fetus and an amniocentesis revealed 45 x0 karyotype and increased concentration of alpha-fetoproteins. Pregnancy was terminated in view of Turner&#x2032;s syndrome. The etiology and natural history of the condition is reviewed

The design and use of plastic balloons for stratospheric research in India

"Plastic balloon flying has been developed at the Tata Institute of Fundamental Research as a research technique which has a number of important applications in India: (a) cosmic ray studies; (b) air sampling in the stratosphere for fall-out measurements; (c) meteorological investigations; (d) astronomical observations; (e) defence research. Comparatively little work has been done till now in these fields at equatorial latitudes, particularly at stratospheric altitudes. Large plastic balloons with volumes of the order of half a million cubic feet, and more, have been constructed by heat welding polyethylene sheeting 0.0015"" thick. With these balloons, successful level flights at altitudes of 110,000 ft. have been achieved; in some cases, individual loads weighing a hundred pounds have been carried up. The most serious problem encountered is the extremely low temperature(about-85DegreeC), of the tropopause at the equatorial latitudes; all known plastics for balloon manufacture become brittle at these low temperatures. To overcome this, dark fabrics have been employed so that the material is heated by solar radiation. The plastic sheeting employed is extruded in India to balloon specifications from chosen polymers. The low temperatures and the turbulent conditions that prevail in the atmosphere at low latitudes present problems in balloon flying which are different from those encountered at high latitudes present in balloon flying which are different from those encountered at high latitudes. The techniques employed, the design of the balloons, and their performance under these conditions are discussed.

Malignant transformation of Syrian hamster embryo (SHE) cells in culture by malachite green: An agent of environniental importance

904-918Malachite green (MG), consisting of green crystals with a metallic lustre, is very soluble in water and is highly cytotoxic to mammalian cells in culture and also acts as a liver tumour promoter. In view of its industrial importance and possible exposure to human beings, MG poses a potential environmental health hazard. Accordingly, we have studied the effect of MG on the formation of free radicals using Electron Spin Resonance (ESR) analysis with 5, 5-dimethyl-1-pyrroline N-oxide (DMPO) as-a spin trapping agent. ESR analysis showed formation of reactive free radicals during exposure of MG to Syrian hamster embryo (SHE) cells. As per mechanism-based toxicology in cancer risk assessment, the chemicals that have the potential to be metabolized to active free radical species could be human cancer hazards. So, we have investigated the effect of MG on the formation of Type II and Type III morphologically transformed foci using SHE cell transformation assay. MG induced dose related transformed foci. Some of these transformed foci were taken out using selective trypsinisation and established immortal cell lines. One of these immortal cell lines was characterized extensively. This immortal cell line showed enhanced DNA synthesis in the form of BrdU incorporation, increased presence of proliferating cell nuclear antigen (PCNA), bcl-2 and p53 proteins by immunohistochemistry. When these immortal cells were injected subcutaneously into nude mice, they developed tumors which were transplantable and histopathologically sarcomas. The present studies indicate that MG could be a potential candidate for two year chemical carcinogenesis rodent bioassays