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371.
Stepkowski SM Kao J Wang ME Tejpal N Podder H Furian L Dimmock J Jha A Das U Kahan BD Kirken RA 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(7):4236-4246
JAK3 is a cytoplasmic tyrosine kinase with limited tissue expression but is readily found in activated T cells. Patients lacking JAK3 are immune compromised, suggesting that JAK3 represents a therapeutic target for immunosuppression. Herein, we show that a Mannich base, NC1153, blocked IL-2-induced activation of JAK3 and its downstream substrates STAT5a/b more effectively than activation of the closely related prolactin-induced JAK2 or TNF-alpha-driven NF-kappaB. In addition, NC1153 failed to inhibit several other enzymes, including growth factor receptor tyrosine kinases, Src family members, and serine/threonine protein kinases. Although NC1153 inhibited proliferation of normal human T cells challenged with IL-2, IL-4, or IL-7, it did not block T cells void of JAK3. In vivo, a 14-day oral therapy with NC1153 significantly extended survival of MHC/non-MHC mismatched rat kidney allografts, whereas a 90-day therapy induced transplantation tolerance (>200 days). Although NC1153 acted synergistically with cyclosporin A (CsA) to prolong allograft survival, it was not nephrotoxic, myelotoxic, or lipotoxic and did not increase CsA-induced nephrotoxicity. In contrast to CsA, NC1153 was not metabolized by cytochrome P450 3A4. Thus, NC1153 prolongs allograft survival without several toxic effects associated with current immunosuppressive drugs. 相似文献
372.
Requirement for CD28 may not be absolute for collagen-induced arthritis: study with HLA-DQ8 transgenic mice 总被引:1,自引:0,他引:1
Taneja V Taneja N Behrens M Griffiths MM Luthra HS David CS 《Journal of immunology (Baltimore, Md. : 1950)》2005,174(2):1118-1125
CD28 is required to achieve optimal T cell activation to an Ag. To determine the role CD28 costimulation plays in collagen-induced arthritis, we have generated DQ8 transgenic, CD28-deficient mice. DQ8 mice deficient for CD28 had comparable numbers of CD4 and CD8 T cells as DQ8.CD28(+/+) mice. DQ8.CD28(-/-) mice develop collagen-induced arthritis with delayed onset and less severity than DQ8.CD28(+/+) mice. T cells from DQ8.CD28(-/-) mice did not respond to type II collagen efficiently in vitro, although the response to DQ8-restricted peptides was similar to that in the parent mice. There was no functional defect in T cells as observed by proliferation with Con A. Cytokine analysis from in vitro study showed the production of high levels of the inflammatory cytokine, IFN-gamma, in response to type II collagen. We observed an increase in CD4(+)CD28(-)NKG2D(+) cells after immunization, suggesting an important role for cells bearing this receptor in the disease process. CD28(-/-) mice also have an increased number of DX5(+) cells compared with CD28(+/+) mice, which can lead to the production of high levels of IFN-gamma. DQ8.CD28(-/-) mice had an increased number of cells bearing other costimulatory markers. Cells from DQ8.CD28(-/-) mice exhibited a lower proliferation rate and were resistant to activation-induced cell death compared with DQ8.CD28(+/+) mice. This study supports the idea that CD28 plays a crucial role in the regulation of arthritis. However, in the absence of CD28 signaling, other costimulatory molecules can lead to the development of disease, thus indicating that the requirement for CD28 may not be absolute in the development of arthritis. 相似文献
373.
Distinct properties and advantages of a novel peroxisome proliferator-activated protein [gamma] selective modulator 总被引:10,自引:0,他引:10
374.
Tau becomes characteristically altered both functionally and structurally in several neurodegenerative diseases now collectively called tauopathies. Although increasing evidence supports that alterations of tau may directly cause neuronal degeneration and cell death, the mechanisms, which render tau to become a toxic agent are still unclear. In addition, it is obscure, whether neurodegeneration in tauopathies occurs via a common mechanism or specific differences exist. The aim of this review is to provide an overview about the different experimental models that currently exist, how they are used to determine the role of tau during degeneration and what has been learnt from them concerning the mechanistic role of tau in the disease process. The review begins with a discussion about similarities and differences in tau alteration in paradigmatic tauopathies such as frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17) and Alzheimer's disease (AD). The second part concentrates on major experimental models that have been used to address the mechanistic role of tau during degeneration. This will include a discussion of cell-free assays, culture models using cell lines or dissociated neurons, and animal models. How these models aid to understand (i) alterations in the function of tau as a microtubule-associated protein (MAP), (ii) direct cytotoxicity of altered tau protein, and (iii) the potential role of tau aggregation in neurodegenerative processes will be the central theme of this part. The review ends with concluding remarks about a general mechanistic model of the role of tau alteration and neuronal degeneration in tauopathies and future perspectives. 相似文献
375.
Molecular Biology Reports - Genus Ocimum is known to have species possessing important therapeutic essential oil. The major phytoconstituents of essential oil in Ocimum species are... 相似文献
376.
Murphy WJ Davis B David VA Agarwala R Schäffer AA Pearks Wilkerson AJ Neelam B O'Brien SJ Menotti-Raymond M 《Genomics》2007,89(2):189-196
We report the construction of a 1.5-Mb-resolution radiation hybrid map of the domestic cat genome. This new map includes novel microsatellite loci and markers derived from the 2X genome sequence that target previous gaps in the feline-human comparative map. Ninety-six percent of the 1793 cat markers we mapped have identifiable orthologues in the canine and human genome sequences. The updated autosomal and X-chromosome comparative maps identify 152 cat-human and 134 cat-dog homologous synteny blocks. Comparative analysis shows the marked change in chromosomal evolution in the canid lineage relative to the felid lineage since divergence from their carnivoran ancestor. The canid lineage has a 30-fold difference in the number of interchromosomal rearrangements relative to felids, while the felid lineage has primarily undergone intrachromosomal rearrangements. We have also refined the pseudoautosomal region and boundary in the cat and show that it is markedly longer than those of human or mouse. This improved RH comparative map provides a useful tool to facilitate positional cloning studies in the feline model. 相似文献
377.
Cooper B Neelam A Campbell KB Lee J Liu G Garrett WM Scheffler B Tucker ML 《Molecular plant-microbe interactions : MPMI》2007,20(7):857-866
Uromyces appendiculatus is a rust fungus that causes disease on beans. To understand more about the biology of U. appendiculatus, we have used multidimensional protein identification technology to survey proteins in germinating asexual uredospores and have compared this data with proteins discovered in an inactive spore. The relative concentrations of proteins were estimated by counting the numbers of tandem mass spectra assigned to peptides for each detected protein. After germination, there were few changes in amounts of accumulated proteins involved in glycolysis, acetyl Co-A metabolism, citric acid cycle, ATP-coupled proton transport, or gluconeogenesis. Moreover, the total amount of translation elongation factors remained high, supporting a prior model that suggests that germlings acquire protein translation machinery from uredospores. However, germlings contained a higher amount of proteins involved in mitochondrial ADP:ATP translocation, which is indicative of increased energy production. Also, there were more accumulating histone proteins, pointing to the reorganization of the nuclei that occurs after germination prior to appressorium formation. Generally, these changes are indicative of metabolic transition from dormancy to germination and are supported by cytological and developmental models of germling growth. 相似文献
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380.
In the present study, butachlor (5, 10, 20, 40 and 80 ppm) induced toxicity in Nostoc muscorum and their degradation was evaluated.
The dose of butachlor dependent decreased in the cell survival and growth of N. muscorum was noticed. Scanning electron
microscopy revealed the adverse impact on the cell size and shapes. Low concentrations of butachlor (10 and 20 ppm) induced the
over expression of a polypeptides of 31.0 K Da and 42.7 K Da, respectively which could be responsible for developing resistance in
the organism up to certain level. Further, the degradation product of butachlor as a result of metabolic activities of N. muscorum,
identified by GC-MS analysis includes phenols and benzene dicarboxylic acid indicating the utilization of herbicide during active
growth. 相似文献