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381.
Rajashree Sampath Puvanakrishnan Rengarajulu 《Molecular and cellular biochemistry》1999,197(1-2):203-208
This study was designed to investigate the alterations in the levels of various proteases such as anglotensin converting enzyme (ACE), kallikrein, aminopeptidases, urokinase and plasmin in serum-heart and kidney and to find out whether the changes in the levels of these enzymes could explain the pathogenests of hypertension induced by Dexamethasone (Dex). Dex was administered to Male Wistar rats (180-200 g body weight) at a dosage of 2.5 mg/kg/week subcutaneously on alternate days for 2 weeks. One more week was included in this investigation to oversee the recovery process. Mean Arterial Pressure (MAP) showed significant elevation during administration and after withdrawal of Dex. The levels of enzymes such as angtotens'm converting enzyme, carboxypeptidase-N and leucine ammopeptidase were found to be elevated in serum as well as in tissues. The level of kallikrein was observed to decrease in serum and tissues and that of thrombin, plasmin and uroldnase exhibited variations. Thus, treatment with Dex altered the levels of these proteases which might have a role in the pathogenesis of hypertension and in altered blood coagulation. 相似文献
382.
Suparna Rudra Somnath Dasmandal Chiranjit Patra Biman Kumar Patel Suvendu Paul 《Journal of biomolecular structure & dynamics》2013,31(14):3773-3790
The interaction between a synthesized dye with proteins, bovine, and human serum albumin (BSA, HSA, respectively) under physiological conditions has been characterized in detail, by means of steady-state and time-resolved fluorescence, UV–vis absorption, and circular dichroism (CD) techniques. An extensive time-resolved fluorescence spectroscopic characterization of the quenching process has been undertaken in conjugation with temperature-dependent fluorescence quenching studies to divulge the actual quenching mechanism. From the thermodynamic observations, it is clear that the binding process is a spontaneous molecular interaction, in which van der Waals and hydrogen bonding interactions play the major roles. The UV–vis absorption and CD results confirm that the dye can induce conformational and micro-environmental changes of both the proteins. In addition, the dye binding provokes the functionality of the native proteins in terms of esterase-like activity. The average binding distance (r) between proteins and dye has been calculated using FRET. Cytotoxicity and antiviral effects of the dye have been found using Vero cell and HSV-1F virus by performing MTT assay. The AutoDock-based docking simulation reveals the probable binding location of dye within the sub-domain IIA of HSA and IB of BSA. 相似文献
383.
We propose a constrained maximum partial likelihood estimator for dimension reduction in integrative (e.g., pan-cancer) survival analysis with high-dimensional predictors. We assume that for each population in the study, the hazard function follows a distinct Cox proportional hazards model. To borrow information across populations, we assume that each of the hazard functions depend only on a small number of linear combinations of the predictors (i.e., “factors”). We estimate these linear combinations using an algorithm based on “distance-to-set” penalties. This allows us to impose both low-rankness and sparsity on the regression coefficient matrix estimator. We derive asymptotic results that reveal that our estimator is more efficient than fitting a separate proportional hazards model for each population. Numerical experiments suggest that our method outperforms competitors under various data generating models. We use our method to perform a pan-cancer survival analysis relating protein expression to survival across 18 distinct cancer types. Our approach identifies six linear combinations, depending on only 20 proteins, which explain survival across the cancer types. Finally, to validate our fitted model, we show that our estimated factors can lead to better prediction than competitors on four external datasets. 相似文献
384.
385.
DNA barcoding to map the microbial communities: current advances and future directions 总被引:1,自引:0,他引:1
Chiranjib Chakraborty C. George Priya Doss Bidhan C. Patra Sanghamitra Bandyopadhyay 《Applied microbiology and biotechnology》2014,98(8):3425-3436
During the last two decades, the DNA barcode development towards microbial community has increased dramatically. DNA barcode development is related to error-free and quick species identification which aid in understanding the microbial biodiversity, as well as the diseases related to microbial species. Here, we seek to evaluate the so-called barcoding initiatives for the microbial communities and the emerging trends in this field. In this paper, we describe the development of DNA marker-based DNA barcoding system, comparison between routine species identification and DNA barcode, and microbial biodiversity and DNA barcode for microbial communities. Two major topics, such as the molecular diversity of viruses and barcode for viruses have been discussed at the same time. We demonstrate the current status and the maker of DNA barcode for bacteria, algae, fungi, and protozoa. Furthermore, we argue about the promises, limitations, and present and future challenges of microbial barcode development. 相似文献
386.
Induction of sister chromatid exchanges by heavy metal salts in root meristem cells ofAllium cepa L.
Four heavy metal salts, nickel sulphate, mercuric chloride, cadmium sulphate and zinc sulphate, were tested for induction
of sister chromatid exchange (SCE) in root meristem cells ofAllium cepa. A simple modified Feulgen staining procedure was employed for SCE-analysis. Maleic hydrazide and paraquat were included
for comparison. An evaluation of genotoxicity of the above test chemicals made on the basis of SCE-assay was found positive
for all the test chemicals with exception of zinc sulphate which gave a weak positive result. 相似文献
387.
388.
Mangrove forests are salt tolerant plants confined to the coastal areas and occupy only 5% of the total forest areas of the
world. These are the most hostile environment with fluctuating tidal and saline regime and a limited plant species can survive
under such condition. Nevertheless, these plants are most valuable resources and provide economic and ecological benefits
to the coastal people. Several mangrove species have been used in traditional medicine or have few applications as insecticide
and pesticide. Mangroves are biochemically unique, producing wide array of natural products with unique bioactivity. They
possess active metabolites with some novel chemical structures which belong to diverse chemical classes such as alkaloids,
phenol, steroids, terpenoids, tannins, etc. The present review examines recent investigations on the biological activities
of extracts and phytochemicals identified from mangroves and their associates as antimicrobial, antiviral, antioxidant, anticancer
and many other properties like antiproliferative, insecticidal, antimalarial, antifeedant, central nervous system depressant
and anti-plasmodial etc. The present article also emphasizes and creates an awareness of potential mangroves and their associates
as a source of novel medicines, agrochemicals and source of many biologically active compounds. 相似文献
389.
390.
RongsenKumzuk Deep Sankar Chini Manojit Bhattacharya Avijit Kar Shampa Patra Bidhan Chandra Patra 《Zeitschrift fur angewandte Ichthyologie》2020,36(2):249-250
The LWRs (length–weight relationships) of four freshwater fish species from medium categorized Doyang reservoir at Wokha District, Nagaland were studied, namely as Garra naganensis Hora, 1921; Devario naganensis Chaudhuri, 1912; Chagunius nicholsi Myers, 1924 and Schistura manipurensis Chaudhuri, 1912. Fish sample were collected in every 15 days interval by cast-nets (1.0 × 1.0 cm mesh size covering the 4.5 m2 areas), gill-nets (0.4–5.0 cm mesh size), scoop-nets (mesh size with 0.3 × 0.3 cm to 0.6 × 0.6 cm) and also from the local fishermen in between July 2017 to January 2019. The regression value of slope (b) is fallen into 2.860–3.115 range with significant correlation values (r2 ≥ .960). 相似文献