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1.
A method for the rapid establishment of normal adult mammalian colonic epithelial cell cultures 总被引:6,自引:0,他引:6
Alda Vidrich Rajeswari Ravindranath Kianbanoo Farsi Stephan Targan 《In vitro cellular & developmental biology. Plant》1988,24(3):188-194
Summary Normal colonic epithelial cell cultures of mammalian origin are required to facilitate the study of both normal cellular functions
as well as pathogenesis of certain (human) colonic diseases. To date, little information is available regarding the growth
requirements of colonic epithelial cells in culture of eitehr animal or human origin. Such data would enable the development
of a long-term culture system for these cells. In this study, we present methodology that results in the establishment of
homogeneous cultures of adult rabbit colonic epithelial reproducibly, quickly, and in quantity. The epithelial nature of the
cultures is unambiguously established by intermediate filament typing using antikeratin antibodies. Such culutres can now
be used for a variety of functional studies as well as to investigate the growth requirements of colonic epithelial in culture.
This work was supported by the Blinder Foundation for Crohn’s Disease Research, Harbor UCLA IBD Center (AM 36200) and grant
AM 27806 from the National Institutes of Health, Bethesda, MD. 相似文献
2.
The opportunity for intensity of selection is studied in two backward caste groups with different occupations, namely Yadava (pastoral) and Vadabalija (fishing) of Bheemunipatnam Taluk of Visakhapatnam District, Andhra Pradesh. The amount of selection intensity is found to be higher in Vadabalija (0.8583) than Yadava (0.5827). The contribution of mortality to the total index of selection is greater in Vadabalija (0.6095) than in Yadava (0.3326). When consanguineity is considered, the fertility components of selection intensity (0.1885) are lower in the consanguineous group of Yadava than in the nonconsanguineous group (0.2845), whereas in Vadabalija they are higher in the consanguineous group (0.5261) than in the nonconsanguineous group (0.2223). 相似文献
3.
M. Rajeswari Pushpa Agrawal S. Pavithra Priya G. R. Sandhya G. M. Pavithra 《Biotechnology and Bioprocess Engineering》2013,18(2):321-325
The biosorption of Cd(II) by Moringa oleifera using a batch system and a continuous up flow mode in a fixed bed column was studied. Batch adsorption experiments were performed as a function of pH, biosorbent dose, contact time, volume of the solution, and initial metal concentration. The adsorption isotherms obtained fitted well into the Freundlich and Langmuir isotherms. The dynamic removal of cadmium by powdered seed of the Moringa oleifera was studied in a packed column. The effect of bed height (4 and 8 cm) and flow rate (2 and 5mL/min) on biosorption process was investigated and the experimental breakthrough curves were obtained. Results showed that by increasing the bed height and decreasing the flow rate, the breakthrough and exhaustion times increased. The break-through time was considered as a measure of the column performance. The maximum break-through time of 320 min was achieved at the operating condition of 2 mL/min influent flow rate and bed height of 8 cm. 相似文献
4.
Bhumika Ray Shweta Agarwal Neelam Lohani Moganty R. Rajeswari 《Journal of biomolecular structure & dynamics》2016,34(11):2518-2535
Certain plant-derived alkaloids and flavonoids have shown propitious cytotoxic acitvity against different types of cancer, having deoxyribose nucleic acid (DNA) as their main cellular target. Flavopiridol, a semi-synthetic derivative of rohitukine (a natural compound isolated from Dysoxylum binectariferum plant), has attained much attention owing to its anticancer potential against various haematological malignancies and solid tumours. This work focuses on investigating interaction between flavopiridol and DNA at molecular level in order to decipher its underlying mechanism of action, which is not well understood. To define direct influence of flavopiridol on the structural, conformational and thermodynamic aspects of DNA, various spectroscopic and calorimetric techniques have been used. ATR-FTIR and SERS spectral outcomes indicate a novel insight into groove-directed-intercalation of flavopiridol into DNA via direct binding with nitrogenous bases guanine (C6=O6) and thymine (C2=O2) in DNA groove together with slight external binding to its sugar–phosphate backbone. Circular dichroism spectral analysis of flavopiridol–DNA complexes suggests perturbation in native B-conformation of DNA and its transition into C-form, which may be localized up to a few base pairs of DNA. UV–visible spectroscopic results illustrate dual binding mode of flavopiridol when interacts with DNA having association constant, Ka = 1.18 × 104 M?1. This suggests moderate type of interaction between flavopiridol and DNA. Further, UV melting analysis also supports spectroscopic outcomes. Thermodynamically, flavopiridol–DNA complexation is an enthalpy-driven exothermic process. These conclusions drawn from this study could be helpful in unveiling mechanism of cytoxicity induced by flavopiridol that can be further applied in the development of flavonoid-based new chemotherapeutics with more specificity and better efficacy. 相似文献
5.
Rajeswari SR Jonnalagadda VS Jonnalagadda S 《Indian journal of biochemistry & biophysics》1999,36(3):137-142
The ATP-dependent phosphorylation of riboflavin to FMN by flavokinase is the key step in flavin biosynthesis. Flavokinase has been purified from a fungal source for the first time. The enzyme purified from a cell wall lacking mutant of Neurospora crassa, slime, is a monomer of M(r) 35.5 kDa with maximal activity at alkaline pH and high temperature (55 degrees C). The K(m) for both substrates is the lowest reported for flavokinase from any source so far (120 nM for riboflavin and 210 nM for MgATP2-). The enzyme exhibits preference for Mg2+ over Zn2+ as the essential activator and is also significantly activated by several cations. Activation by orthophosphate may be physiologically relevant for the intracellular regulation of flavokinase. 相似文献
6.
SWAP-70 regulates c-kit-induced mast cell activation, cell-cell adhesion, and migration 总被引:3,自引:0,他引:3
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SWAP-70, an unusual phosphatidylinositol-3-kinase-dependent protein that interacts with the RhoGTPase Rac, is highly expressed in mast cells. Cultured bone marrow mast cells (BMMC) from SWAP-70(-/-) mice are reduced in FcepsilonRI-triggered degranulation. This report describes the hitherto-unknown role of SWAP-70 in c-kit receptor signaling, a key proliferation and differentiation pathway in mast cells. Consistent with the role of Rac in cell motility and regulation of the actin cytoskeleton, mutant cells show abnormal actin rearrangements and are deficient in migration in vitro and in vivo. SWAP-70(-/-) BMMC are impaired in calcium flux, in proper translocation and activity of Akt kinase (required for mast cell activation and survival), and in translocation of Rac1 and Rac2 upon c-kit stimulation. Adhesion to fibronectin is reduced, but homotypic cell association induced through c-kit is strongly increased in SWAP-70(-/-) BMMC. Homotypic association requires extracellular Ca(2+) and depends on the integrin alpha(L)beta(2) (LFA-1). ERK is hyperactivated upon c-kit signaling in adherent and dispersed mutant cells. Together, we suggest that SWAP-70 is an important regulator of specific effector pathways in c-kit signaling, including mast cell activation, migration, and cell adhesion. 相似文献
7.
Zhang W Singam R Hellermann G Kong X Juan HS Lockey RF Wu SJ Porter K Mohapatra SS 《Genetic vaccines and therapy》2004,2(1):8-10
BACKGROUND: The need for safe and effective treatment of dengue virus (DEN), a class A agent that causes dengue hemorrhagic fever/dengue shock syndrome, has been a critical global priority. An effective vaccine for DEN is not yet available. In this study the possibility of attenuating DEN infection using adeno-associated virus (AAV)-encoded short interfering RNAs (siRNA) was examined in Vero cells and human dendritic cells (DCs). METHODS: A cassette encoding siRNA targeted to a 3' untranslated sequence common to all DEN serotypes was designed and tested for its ability to attenuate DEN infection by use of AAV delivery. RESULTS: Vero cells or DCs infected with AAV-siRNA showed a significant, dose-dependent reduction in DEN infection. Treatment of DCs with AAV-siRNA also decreased the DEN-induced apoptosis of DCs and did not induce significant inflammation. CONCLUSION: These results demonstrate that AAV-mediated siRNA delivery is capable of reducing DEN infection in cells and may be useful in decreasing DEN replication in humans. 相似文献
8.
The significance of alpha 5 beta 1 integrin dependent and independent actin cytoskelton organization in cell transformation and survival 总被引:3,自引:0,他引:3
Cell-matrix and cell-cell interactions are important physiological determinants of cell growth, survival and transformation. Cell adhesion to the extra cellular matrix (ECM) via integrins also crucially influences the organization of the cytoskeleton. It triggers a cascade of intracellular biochemical events, which regulate cell viability and growth. We have studied the relationship between cell attachment to the substratum and cytoskeletal organization and cell survival and transformation. Our results demonstrate that in the absence of attachment to the substratum, adhesion-dependent fibroblasts exhibit rapid loss of viability. However, a small percentage of cells survive even after remaining non-adherent for 16h. The adherent and non-adherent cells differ from one another both morphologically and physiologically. The latter show a loss of alpha5beta1 integrin expression on their surface and bind non-specifically to the substratum and ECM, thereby activating certain pathways more efficiently than adherent cells. We have also shown that non-adherent cells grow faster and have worse cytoskeletal organization after attachment to the substratum, and do not form focal adhesions or actin stress fibres. Hence, our data suggests that rat fibroblasts in prolonged suspension exhibit some properties that are comparable to cells undergoing transformation, by adapting integrin-dependent or independent signalling pathways for their survival. 相似文献
9.
Reddy BV Rajeswari N Sarangapani M Roopa Reddy G Madan Ch Pranay Kumar K Srinivasa Rao M 《Bioorganic & medicinal chemistry letters》2011,21(21):6510-6514
Indole and its derivatives undergo smooth conjugate addition onto en-1,4-dione derived from isatin and acetophenone, in the presence of a catalytic amount of molecular iodine in acetonitrile under mild conditions to afford a novel class of 3-(1-(1H-indol-3-yl)-2-oxo-2-phenylethyl)indolin-2-one derivatives in good yields with high degree of 1,4-selectivity. Some of these compounds are found to exhibit modest antibacterial and antifungal properties. 相似文献
10.