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981.
High-resolution two-dimensional gel electrophoresis (2-DE) and database analysis was used to establish protein expression patterns for cultured normal human mammary epithelial cells and thirteen breast cancer cell lines. The Human Breast Epithelial Cell database contains the 2-DE protein patterns, including relative protein abundances, for each cell line, plus a composite pattern that contains all the common and specifically expressed proteins from all the cell lines. Significant differences in protein expression, both qualitative and quantitative, were observed not only between normal cells and tumor cells, but also among the tumor cell lines. Eight percent (56/727) of the consistently detected proteins were found in significantly (P< 0.001) variable levels among the cell lines. Eight proteins present in normal cultured breast epithelial cells were not detected in any of the tumor cell lines. We identified a subset of the differentially expressed proteins using a combination of immunostaining, protein sequencing, comigration, and subcellular fractionation. These identified proteins include the intermediate filament components vimentin and cytokeratins. The cell lines can be classified into four distinct groups based on their intermediate filament protein profile. We also identified heat shock proteins; hsp27 and hsp60 varied in abundance and in some cases in the relative phosphorylation levels among the cell lines. Many of the differentially expressed proteins we identified have roles in cellular proliferation and differentiation, including annexin V, elongation initiation factor 5A, Rho GDP dissociation inhibitor, and prohibitin. We identified inosine-5-monophosphate dehydrogenase in each of the cell lines, and found the levels of this enzyme in the tumor cell lines elevated 2- to 20-fold relative to the levels in normal cells. These results expand the human breast epithelial cell protein database (http:// www.anl.gov/CMB/PMG) which is being built to assist researchers with the identification of abnormal patterns of expression and pathways associated with malignancy.  相似文献   
982.
The X-ray structure of tryptophanase (Tnase) reveals the interactions responsible for binding of the pyridoxal 5'-phosphate (PLP) and atomic details of the K+ binding site essential for catalysis. The structure of holo Tnase from Proteus vulgaris (space group P2(1)2(1)2(1) with a = 115.0 A, b = 118.2 A, c = 153.7 A) has been determined at 2.1 A resolution by molecular replacement using tyrosine phenol-lyase (TPL) coordinates. The final model of Tnase, refined to an R-factor of 18.7%, (Rfree = 22.8%) suggests that the PLP-enzyme from observed in the structure is a ketoenamine. PLP is bound in a cleft formed by both the small and large domains of one subunit and the large domain of the adjacent subunit in the so-called "catalytic" dimer. The K+ cations are located on the interface of the subunits in the dimer. The structure of the catalytic dimer and mode of PLP binding in Tnase resemble those found in aspartate amino-transferase, TPL, omega-amino acid pyruvate aminotransferase, dialkylglycine decarboxylase (DGD), cystathionine beta-lyase and ornithine decarboxylase. No structural similarity has been detected between Tnase and the beta 2 dimer of tryptophan synthase which catalyses the same beta-replacement reaction. The single monovalent cation binding site of Tnase is similar to that of TPL, but differs from either of those in DGD.  相似文献   
983.
Two distinct and complementary pathways, one mediated by perforin and the other dependent upon CD95 (Fas), effect cell-mediated cytotoxicity. We examined the relative roles of these pathways in host defenses against the intracellular bacterial pathogen Listeria monocytogenes by using murine listeriosis as a model system. Mice which lacked both perforin and Fas (P0L0) were generated, and their responses to primary and secondary listeriosis were compared to those of wild-type (WT), Fas-deficient (L0), and perforin knockout (P0) mice. Relative to WT mice during primary listeriosis, P0 mice exhibited a reduced capacity to clear the infection from their spleens but not their livers whereas L0 mice had elevated bacterial titers in their livers and a modestly increased titer in their spleens. In contrast, bacterial titers in P0L0 mice were increased approximately 50- to 560-fold in their spleens and 230- to 1, 000-fold in their livers; eventual clearance of listeriae from both organs was significantly delayed. Furthermore, the resistance of P0L0 mice to secondary listeriosis was significantly reduced in their spleens and livers compared to that of WT, P0, or L0 mice. In vitro experiments indicated that immune cytotoxic T lymphocytes (CTL) lysed L. monocytogenes-infected hepatocytes primarily via a Fas-dependent, perforin-independent mechanism. The absence of Fas severely abrogated the lysis of infected hepatocytes by immune CD8(+) CTL. Taken together, these results provide the first evidence for Fas-dependent CTL-mediated lysis of L. monocytogenes-infected hepatocytes and demonstrate complementary roles for Fas and perforin in host defenses against an intracellular bacterial pathogen.  相似文献   
984.
Animal studies show FC-23 to be a promising magnetic resonance imaging indicator of regional cerebral blood flow. In a Phase 1, dose ranging (investigative new drug) study, neuropsychological (NP) tests, subjective ratings, and intensive physiological monitoring were used to determine the maximum tolerated concentration of FC-23 for human application. Five normal healthy male volunteers were exposed to concentrations of FC-23 between 10% and 60% [randomly interleaved with exposures to both room air and 40% nitrous oxide (N2O)] in a within-subjects, double-blind design. Analyses of individual cases and ranked group data showed that individuals tolerated the 30% concentration of FC-23 according to established criteria. Planned comparisons indicated that inhalation of FC-23 produced smaller NP changes and fewer negative symptoms than 40% N2O but poorer NP performance and more negative symptoms than room air. This study indicated that FC-23 is not inert and that humans do not tolerate concentrations suitable for current MRI technology. NP and subjective data assisted in characterizing the sedative effect of FC-23.  相似文献   
985.
Computed tomography assesses the linear coefficient of X-ray radiation decrease in the tissue and hence determines changes in its density thus allowing one to control the destruction of tumor cells and tissues during treatment. The paper proposes a procedure for determining the sizes and density of a tumor along the chosen linear direction crossing the image of a pathological focus. The whole procedure is performed by the special computer programme "Diaglmag". The equations that characterize the dynamics of using the parameters used before, during, and after treatment are presented. Baseline information on the optic image densities on a computer tomogram is obtained with a graphic scanner. The examples presented in the paper show it feasible to solve a difficult task to determine the effect of treatment. This enables a treatment regimen to be corrected in time or modified.  相似文献   
986.
A Mycobacterium sp., strain KR2 which was able to utilise pyrene as sole source of carbon and energy was isolated from a polycyclic aromatic hydrocarbon (PAH) contaminated soil originating from the area of a former gaswork plant. The isolate metabolised up to 60% of the pyrene added (0.5 mg/mL) within 8 days at 20 degrees C. Cis-4,5-pyrene dihydrodiol, 4,5-phenanthrene dicarboxylic acid, 1-hydroxy-2-naphthoic acid, 2-carboxybenzaldehyde, phthalic acid, and protocatechuic acid were identified as degradation products. Based on these findings a degradation pathway for pyrene is suggested which is in good accordance with the data published so far on bacterial pyrene metabolism.  相似文献   
987.
The aim of the present study was to make a clinical and angiographic assessment of early outcomes of the use of heparin-coated new "Jo Stents M". The Study comprised 41 patients who were implanted a heparin-coated new "Jo Stent M". There was an immediate success in 45 (97.6%) of 46 cases, the optimal angiographic and suboptimal (the maximum residual stenosis (13%)) results being achieved in 43 (93.4%) and 2 (4.4%) cases, respectively. The first success of the procedure was 97.8%. Due to acute stent thrombosis, acute occlusion with evolving myocardial infarction occurred in 1 (2.4%) patient. Following the procedure, the mean proportion of the stenotic diameter was (-5.8 +/- 6)%. After the procedure, the minimum stenotic diameter with the mean due diameter of 2.9 +/- 0.5 mm was 3.0 +/- 0.2 mm. The procedure-induced diameter increase was 2.1 +/- 0.5 mm. The total number of lateral branches involved in the stenting area was 11 (100%), 2 (18.2) of them closed after stent implantation. Two branches came into the stenting area in 1 (2.4%) case. At discharge, angina pectoris was absent in 30 (74%) patients. The heparin-coated "Jo Stent M" are effective and safe in treating patients with various clinical and angiographic manifestations of coronary atherosclerotic lesions.  相似文献   
988.
989.
The present cross-sectional study analyzed the extent to which illness perceptions and coping strategies (as measured by the Illness Perception Questionnaire and the Utrecht Coping List, respectively) are associated with levels of daily functioning, as indicated by the Medical Outcomes Study SF-20, and disease-specific measures in 244 adults: 84 with rheumatoid arthritis (RA); 80 with chronic obstructive lung disease (COPD); and 80 with psoriasis. The results of stepwise regression analyses indicated that a strong illness identity, passive coping, belief in a long illness duration, belief in more severe consequences, and an unfavorable score on medical variables were associated with worse outcome on disease-specific measures of functioning and on general role and social functioning. Coping by seeking social support and beliefs in controllability/curability of the disease were significantly related to better functioning. The implications of these findings for future interventions and research are discussed.  相似文献   
990.
OBJECTIVE: Because C5a induces tissue injury by activating polymorphonuclear leukocytes, the hypothesis was that inhibition of C5a activity would reduce cardioplegia-related injury. METHODS: Pigs were placed on cardiopulmonary bypass. The hearts were arrested for 1 hour with hyperkalemic cardioplegia. Pigs were then separated from bypass, and the hearts were reperfused for 2 hours. Anti-porcine C5a monoclonal antibody (1.6 mg/kg, intravenously; n = 6) was administered 20 minutes before the onset of cardiopulmonary bypass. Six pigs received saline solution vehicle. Reactivity of coronary arterioles was studied in vitro with videomicroscopy. Microvessels from uninstrumented pigs served as controls for vascular studies. RESULTS: Endothelium-dependent relaxation to adenosine diphosphate (percent relaxation of precontraction) was reduced after cardioplegic reperfusion (63% +/- 14% vs 77% +/- 10% in control at 10 micromol/L; P =.01). This impairment in endothelium-dependent relaxation was improved with anti-porcine C5a monoclonal antibody (80% +/- 22%; P =.01 vs saline solution), as was the impaired endothelium-dependent relaxation to clonidine (64% +/- 12% control; 26% +/- 17% saline solution; 55% +/- 24% anti-porcine C5a monoclonal antibody at 10 micromol/L; P =.01 saline solution vs control or anti-porcine C5a monoclonal antibody). Myeloperoxidase activity was significantly decreased (0.2 +/- 0.2 units/g protein; P =.04) in the anti-porcine C5a monoclonal antibody group compared with 5.2 +/- 2.7 in the saline solution group. CH50 2 hours after bypass was not statistically different (0.57 +/- 0.41 unit and 0.65 +/- 0.41 unit, respectively) between the anti-porcine C5a monoclonal antibody and saline solution groups. Despite less myocardial polymorphonuclear leukocyte infiltration after C5a inhibition, maximum rate of rise of left ventricular pressure, percent segmental shortening, and blood flow through the left anterior descending coronary artery were similar in the anti-porcine C5a monoclonal antibody and saline solution groups. CONCLUSIONS: Inhibition of C5a limits neutrophil-mediated impairment of endothelium-dependent relaxation after cardiopulmonary bypass and cardioplegic reperfusion, but it has no effect on short-term myocardial functional preservation.  相似文献   
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