Expression of conserved signalling pathway genes during spontaneous vascular differentiation of R1 embryonic stem cells and in Py-4-1 endothelial cells

Embryonic stem (ES) cells are an invaluable model for identifying subtle phenotypes as well as severe outcomes of perturbing gene function that may otherwise result in lethality. However, though ES cells of different origins are regarded as equally pluripotent, their in vitro differentiation potential varies, suggesting that their response to developmental signals is different. The R1 cell line is widely used for gene manipulation due to its good growth characteristics and highly efficient germline transmission. Hence, we analysed the expression of Notch, Wnt and Sonic Hedgehog (Shh) pathway genes during differentiation of R1 cells into early vascular lineages. Notch-, Wnt- and Shh-mediated signalling is important during embryonic development. Regulation of gene expression through these signalling molecules is a frequently used theme, resulting in context-dependent outcomes during development. Perturbing these pathways can result in severe and possibly lethal developmental phenotypes often due to primary cardiovascular defects. We report that during early spontaneous differentiation of R1 cells, Notch-1 and the Wnt target Brachyury are active whereas the Shh receptor is not detected. This expression pattern is similar to that seen in a mouse endothelial cell line. This temporal study of expression of genes representative of all three pathways in ES cell differentiation will aid in further analysis of cell signalling during vascular development

Preliminary Screening of Antibacterial Compounds from Palar River Basin Flora

Considering the significance of phytochemicals as antimicrobial agents, attempt was made in the present study, to categorize several rare plant species present in and around Palar river basin and to assess their antimicrobial activity. The densities of the green cover of the Palar river basin flora were assessed by the Google Earth software. Totally 28 plants were identified and classified into 17 families according to binomial classification system. Plant extracts were prepared from leaves of all collected plants by using methanol and chloroform. Thus, the crude methanol and chloroform extracts of 28 plant species were subjected to preliminary screening against 6 strains of human bacterial pathogen using the dick diffusion method at 500 µg/disc concentrations. The results indicated that 21 different plant species exhibited activity against one or more of the bacteria while four species, viz., Ammania baccifera, Plectranthus sp., Vitex trifolia and Vitex negundo showed activity against all test organisms. The plants containing bioactive metabolites demonstrated stronger anti-microbial properties stressing the need for further investigations using fractionated extracts and purified chemical components

Panorama of neoplasms of upper GI tract: a 5 year research study

Background: The diseases of the gastrointestinal tract (GIT) are the most common and leading cause of morbidity and mortality than the disorders of any other systems of the body. Gastrointestinal (GI) tract tumors are one of the most common cancers accounting for 11% of all cancers. Among these tumors, upper gastrointestinal tract malignancies are quite aggressive with a dismal prognosis. Malignant tumors are most common than benign. The most common carcinoma of the esophagus is Squamous cell carcinoma (SCC). Incidence of SCC is less than 5 per 100,000 populations in males and 1 per 100,000 populations in females. Gastric cancer was the second most common cancer in the World and 60% of them occurred in developing countries. The most common carcinoma of the Stomach is Adenocarcinoma.Aim & Objectives: To study the spectrum of neoplastic lesions of the upper gastrointestinal tract by the examination of endoscopic biopsies and surgically resected specimens. To determine the degree of severity of the malignancies by assessing the depth of invasion, Lymph nodal & Omental spread.Methods: The present study is both retrospective & prospective study for a period of 5 years from January 2007 to December 2011. The sample size includes all the endoscopic biopsies & surgically resected specimens of gastrointestinal tract received at Department of Pathology, S.V. Medical College, Tirupati. The study also obtained clearance from the ethical committee of the institution. The biopsy specimens thus obtained were fixed in 10% buffered neutral formalin. The sections were stained routinely with H & E. Special stains and IHC done wherever necessary.Results: we have received 120 specimens regarding the upper gastrointestinal system. Among these 120 specimens, 71 specimens were endoscopic biopsies & 49 specimens were surgically resected specimens. Out of 71 Endoscopic biopsies 28 biopsies were malignant among which 2 was esophagus and 26 were stomach. Out of 49 surgically resected specimens 1 was benign and 32 were malignant tumors. Out of 59 neoplasms of stomach there were single cases each of Sub mucosal Lipoma, Malignant lymphoma, GIST & 56 cases of Adenocarcinoma & its variants were noted.Conclusion: Most of the neoplasms are of stomach (97%). All the neoplasms are malignant except one benign lesion sub mucous lipoma of stomach. Most of the neoplasms of stomach were Adenocarcinoma (96.5%). Both tumors of esophagus were squamous cell carcinoma occurred after 50 years of age.

Human BCAS3 Expression in Embryonic Stem Cells and Vascular Precursors Suggests a Role in Human Embryogenesis and Tumor Angiogenesis

Cancer is often associated with multiple and progressive genetic alterations in genes that are important for normal development. BCAS3 (Breast Cancer Amplified Sequence 3) is a gene of unknown function on human chromosome 17q23, a region associated with breakpoints of several neoplasms. The normal expression pattern of BCAS3 has not been studied, though it is implicated in breast cancer progression. Rudhira, a murine WD40 domain protein that is 98% identical to BCAS3 is expressed in embryonic stem (ES) cells, erythropoiesis and angiogenesis. This suggests that BCAS3 expression also may not be restricted to mammary tissue and may have important roles in other normal as well as malignant tissues. We show that BCAS3 is also expressed in human ES cells and during their differentiation into blood vascular precursors. We find that BCAS3 is aberrantly expressed in malignant human brain lesions. In glioblastoma, hemangiopericytoma and brain abscess we note high levels of BCAS3 expression in tumor cells and some blood vessels. BCAS3 may be associated with multiple cancerous and rapidly proliferating cells and hence the expression, function and regulation of this gene merits further investigation. We suggest that BCAS3 is mis-expressed in brain tumors and could serve as a human ES cell and tumor marker

RNA-based therapeutic approaches for FTDP-17

Neurodegenerative diseases are linked to altered splicing mechanisms (Mills et al., 2012). Fronto temporal dementia and parkinsonism linked to chromosome 17 (FTDP-17) is one such disease that stems from the differential splicing caused due to mutations in Microtubule associated protein tau (MAPT) gene (Esther et al., 2002). This PhD thesis focuses on developing RNA-based therapeutic approaches to address FTDP-17. CHAPTER 1 introduces a broad range of topics such as splicing mechanism, neurodegenerative diseases associated with splice defects, therapeutic tools to modulate such splice defects in the context of neurogenetic diseases and possible applications of available tools for FTDP-17. CHAPTER 2 explores an exon skipping strategy to modulate splice defects in the context of FTD-17 using small nuclear RNAs (snRNAs). CHAPTER 3 is based on a short interfering RNA (siRNA) approach to modulate post-transcriptional gene silencing of specific isoform associated to FTDP-17. CHAPTER 4 employs long non coding RNA (lncRNA) to mediate post transcriptional repression of tau protein associated to FTDP-17 and deciphers its auxiliary role in splicing of exon 10 CHAPTER 5 elaborates on the future perspectives of all the above mentioned approaches to find a cure for FTDP-17

Rudhira is a cytoplasmic WD40 protein expressed in mouse embryonic stem cells and during embryonic erythropoiesis

We describe a novel murine gene rudhira that is expressed at high levels in embryonic stem cells and is restricted to blood islands and the erythroid lineage during embryonic development. Rudhira is expressed in angiogenic precursors but is excluded from the differentiated endothelium. Rudhira-expressing cells are seen in close proximity to endothelial cells in angiogenic blood vessels. Rudhira encodes a predicted cytoplasmic WD40 protein that is 98% identical to human BCAS3. The gene encoding BCAS3 maps to a breakpoint of hematological neoplasms on human chromosome 17q23, but its expression and function remain to be determined. We demonstrate that mouse Rudhira is a novel marker for analysis of the erythroid lineage

Synthesis and characterization of polyaniline nano-fibers

207-209Polyaniline (PANI) nanofibers were synthesized by polymerization of aniline in the presence of hydrochloric acid as a catalyst and ammoniumperoxidisulphate as an oxidant by the chemical oxidative polymerization method. The product powder was pelletized with the help of hydraulic machine to study the XRD, SEM and SANS. The XRD pattern indicates semi -crystalline nature of PANI with interplanar distance 4.210Ǻ and 3.774 Ǻ, respectively. The SEM pictures show fiber like nature of particles. SANS experiment is used to find different parameters of these crystalline polymer nano-fiber particles. Dynamic light scattering (DLS) studies are performed to find the sizes of nano structured polyaniline. </span