The Effect of w−termw-term on Visibility Correlation and Power Spectrum Estimation

Visibility-visibility correlation has been proposed as a technique for the estimation of power spectrum, and used extensively for small field of view observations, where the effect of $w-term$ is usually ignored. We consider power spectrum estimation from the large field of view observations, where the $w-term$ can have a significant effect. Our investigation shows that a nonzero $w$ manifests itself as a modification of the primary aperture function of the instrument. Using a gaussian primary beam, we show that the modified aperture is an oscillating function with a gaussian envelope. We show that the two visibility correlation reproduces the power spectrum beyond a certain baseline given by the width, $U_{w}$ of the modified aperture. Further, for a given interferometer, the maximum $U_{w}$ remains independent of the frequencies of observation. This suggests that, the incorporation of large field of view in radio interferometric observation has a greater effect for larger observing wavelengths.Comment: 9 pages, 4 figures, 2 table

IN-VITRO CYTOTOXICITY ANALYSIS OF TAMOXIFEN CITRATE LOADED CROSS-LINKED GUAR GUM NANOPARTICLES ON JURKAT (HUMAN T-CELL LEUKEMIA) CELL LINE

The present investigation was aimed to study the antiproliferative action of tamoxifen citrate (TMX), a non steroidal antiestrogen, on a human T-cell leukemia cell line, Jurkat, as free drug and TMX loaded guar gum nanoparticles. For this we developed a new formulation containing chemically cross-linked guar gum nanoparticles (GG NPs) loaded with tamoxifen citrate (TMX). Single step (oil in water) emulsion and in-situ polymer cross-linking technique was employed to prepare spherical and smooth surfaced nanoparticles in the size range of 200-300nm. Nanoparticle size and shape was confirmed from observation in transmission electron microscope (TEM) analysis. Cytotoxicity on Jurkat (human T-cell leukemia) cell lines as determined by cell growth inhibition after 48 hrs of incubation indicated that tamoxifen citrate loaded guar gum nanoparticles were as efficient as the free drug when applied to the cancer line. However, the crosslinked guar gum nanoparticles loaded with tamoxifen citrate exhibited sustained release of the drug and delayed apoptosis over a long period of time making it suitable for cancer treatment. Keywords: Nanoparticles, guar gum, tamoxifen citrate, Jurkat (human T-cell leukemia) cell line, cytotoxicity, cell death, WST-1 assay

Galectin-3: A potential target for cancer prevention

Protein-carbohydrate interactions play significant role in modulating cell-cell and cell-extracellular matrix interactions, which, in turn, mediate various biological processes such as growth regulation, immune function, cancer metastasis, and apoptosis. Galectin-3, a member of the β-galactoside-binding protein family, is found multifunctional and is involved in normal growth development as well as cancer progression and metastasis, but the detailed mechanisms of its functions are not well understood. This review discusses its structure, binding properties, transcriptional regulation and roles in homotypic/heterotypic cell adhesion, angiogenesis and apoptosis

Tunicamycin induced endoplasmic reticulum stress promotes apoptosis of prostate cancer cells by activating mTORC1

Studies suggest that tunicamycin may work as a therapeutic drug to cancer cells by inducing stress in the endoplasmic reticulum (ER) through unfolded protein response (UPR) and thereby promoting apoptosis. However, mechanisms of the prolonged activation of the UPR under sustained ER stress in the regulation of cell apoptosis are largely unknown. To delineate the role of candidate genes in the apoptotic process under ER stress and to search for new therapeutic strategies to treat metastatic castration resistant prostate cancer, we performed whole genome expression microarray analysis in tunicamycin treated metastatic androgen-insensitive prostate cancer cells, PC-3. Among several induced genes, the expression of eNOS (NOS3) gene was remarkably high. The increased expression of eNOS activates mTORC1 through RagC. This results into an accumulation of p62 (SQSTM1) which facilitates aggregation of ubiquitinated protein thus compromising clearance of misfolded toxic protein aggregates. Lastly, association of p62 proteins and misfolded proteins promote reactive oxygen species (ROS) mediated mitochondrial apoptosis. Overall, our data demonstrate that tunicamycin induced ER stress promotes prostate cancer cell death by activating mTORC1 through eNOS-RagC pathway

Studies on Reproductive Development and Breeding Habit of the Commercially Important Bamboo <i>Bambusa tulda</i> Roxb

Compared to other grasses, flowering in bamboo is quite divergent, yet complex with respect to time to flower, number of individual culms in a population that have been induced at a time (sporadic vs. gregarious), nature of monocarpy, morphology of inflorescences (solitary spikelet vs. pseudospikelet), biology of pollen and nature of genetic compatibility. Wide diversity exists even across species and genotypes. However, due to the rarity of flowering and inaccessibility, few studies have been done to systematically analyse diverse aspects of the reproductive behaviour of bamboo. In this study, four recurrently occurring, sporadic flowering populations of Bambusa tulda have been closely observed over the last seven years. Detailed inflorescence and floral morphology and development of reproductive organs have been studied. Pollen viability was assessed by staining and in vitro germination. Self and cross pollination experiments were performed in a plantation site to assess the genetic nature of pollen-pistil interaction. The study identifies interesting reproductive features, that are not common in other grasses. A few important observations include the early appearance of a solitary spikelet vs. late appearance of a pseudospikelet in the flowering cycle, low rate of pollen germination, protandry, self-incompatibility and higher rate of seed setting by the pseudospikelet as compared to the solitary spikelet. The findings will not only be useful to understand the reproductive behaviour of this non-woody timber plant, but will also be useful for forest management and sustainable use of bamboo bioresources