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61.
The major glomerular abnormalities in hypertensive nephrosclerosis are described as glomerular obsolescence (GO), glomerulosclerosis (GS), and glomerular collapse (GC). However, glomerular cellular changes caused by hypertensive insults have not been well analyzed. Using an immunoenzyme method, we examined eleven biopsy samples from patients with hypertensive nephrosclerosis for two synthetic and secreting phenotypes, a-smooth muscle actin (alpha-SMA) and collagen type III (Col. III), and two apoptotic phenotypes, pro-apoptotic molecule Bax and anti-apoptotic molecule BcI-2. Together with the glomerular and vascular changes and interstitial fibrosis (IF) area, the results were scored quantitatively and semi-quantitatively and compared to the clinical findings, which included systolic blood pressure (SBP), mean arterial pressure (MAP), serum creatinine levels (sCr) and creatinine clearance (Ccr), using univariate and multivariate analyses. As a result, GS was frequently observed in the mild-to-moderate hypertensive group (140 < or = SBP<180 mmHg), whereas GC was positively correlated with SBP. Furthermore, there was a positive correlation of GS with mesangial alpha-SMA and Col. III, suggesting that GS was the reflection of these synthetic and secreting phenotypic changes in mesangial cells. Endothelial Bax was positively correlated with Ccr (p<0.01); in contrast, podocytic Bax was positively correlated with sCr (p<0.05) and showed a tendency to correlate with MAP (p=0.054). In conclusion, these findings support the view that mesangial synthetic and secreting phenotypic changes may be a reflection of cellular activation caused by mild-to-moderate hypertension and that apoptotic phenotypic expression in podocytes, rather than endothelial cells, may be related to the development of a severe form of hypertensive nephrosclerosis.  相似文献   
62.
The norA gene cloned from chromosomal DNA of a quinolone-and methicillin-resistant Staphylococcus aureus strain conferred resistance to hydrophilic quinolones such as norfloxacin, enoxacin, ofloxacin, and ciprofloxacin, but no or less resistance to hydrophobic ones such as nalidixic acid, oxolinic acid, and sparfloxacin in S. aureus and Escherichia coli. Nucleotide sequence analysis of the cloned DNA fragment revealed that the norA gene could code for a protein consisting of 388 amino acid residues with a molecular weight of 42,265, which was consistent with the experimental value of about 49,000 obtained on DNA-directed translation. The deduced NorA polypeptide has 12 hydrophobic membrane-spanning regions and is partly homologous to tetracycline resistance protein and sugar transport proteins. The uptake of a hydrophilic quinolone, enoxacin, by S. aureus harboring a plasmid carrying the norA gene was about 50% of that by the parent strain lacking the plasmid, but it increased to almost the same level as that by the latter strain with carbonyl cyanide m-chlorophenyl hydrazone. On the other hand, the uptake of a hydrophobic quinolone, sparfloxacin, was hardly affected by the norA gene. These results suggest that the NorA polypeptide may constitute a membrane-associated active efflux pump of hydrophilic quinolones.  相似文献   
63.
Mechanical stimulation is known to be an essential factor in the regulation of cartilage metabolism. We tested the hypothesis that expression of lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) can be modulated by cyclic tensile stretch load in chondrocytes. Cyclic loading of repeated stretch stress at 10 cycles per minute with 10 kPa of stress for 6 h induced expression of LOX-1 to 2.6 times control in cultured bovine articular chondrocytes, equivalent to the addition of 10 microg/mL oxidized low density lipoprotein (ox-LDL) (2.4 times control). Application of the cyclic load to the chondrocytes along with 10 microg/mL ox-LDL resulted in synergistically increased LOX-1 expression to 6.3 times control. Individual application of cyclic loading and 10 microg/mL ox-LDL significantly suppressed chondrocytes viability (84.6% +/- 3.4% and 80.9% +/- 3.2% of control at 24 h, respectively; n = 3; p < 0.05) and proteoglycan synthesis [81.0% +/- 7.1% and 85.7% +/- 5.2% of control at 24 h, respectively; p < 0.05 when compared with 94.6% +/- 4.6% for native-LDL (n = 3)]. Cyclic loading and 10 microg/mL ox-LDL synergistically affected cell viability and proteoglycan synthesis, which were significantly suppressed to 45.6% +/- 4.9% and 48.7% +/- 6.7% of control at 24 h, respectively (n = 3; p < 0.01 when compared with individual application of cyclic loading or 10 microg/mL ox-LDL). In this study, we demonstrated synergistic effects of cyclic tensile stretch load and ox-LDL on cell viability and proteoglycan synthesis in chondrocytes, which may be mediated through enhanced expression of LOX-1 and which has important implications in the progression of cartilage degeneration in osteoarthritis.  相似文献   
64.
We compared the cytotoxic effects of two anthracycline derivatives, epirubicin (EPI) and adriamycin (ADM), against human tumor cells in vitro. Various tumor specimens, obtained at surgery, included 57 liver, 19 lung, 16 gastric, 10 colorectal and 7 breast cancer specimens. These tumor cells were exposed to the same concentration of EPI or ADM for 3 days. The chemosensitivity of each tumor cell type to each drug was then assayed using the in vitro succinate dehydrogenase inhibition (SDI) test. Sensitivity to the treatment was defined as a 50% or greater reduction in the succinate dehydrogenase (SD) activity of the tumor cells, relative to that of the control (untreated) cells. Each cell type, except for gastric cancer cells, was equally sensitive to EPI and ADM. Gastric cancer cells were more sensitive to EPI than to ADM (P less than 0.05). The rate of coincidence, the sum of the co-sensitive and co-resistant rates of all the tumors, was quite high (90.8%). Thus, these findings indicate that EPI and ADM are equally cytotoxic to each tumor cell type, but EPI is more cytotoxic than ADM to gastric cancer cells. Since EPI is reported to be less cardiotoxic than ADM, EPI may replace ADM in cancer chemotherapy.  相似文献   
65.
The excitatory responses of deflationary slowly adapting pulmonary stretch receptor (SAR) activity to lung deflation ranging from approximately -15 to -25 cm of H(2)O for approximately 5 s were examined before and after administration of flecainide, a Na(+) channel blocker, and K(+) channel blockers, such as 4-aminopyridine (4-AP) and tetraethylammonium (TEA). The experiments were performed in anesthetized, artificially ventilated rats after unilateral vagotomy. The deflationary SARs increased their activity during lung deflation and its effect became more pronounced by increasing the degree of negative pressure. During lung deflation the average values for the deflationary SAR adaptation index (AI) were below 40%. Intravenous administration of veratridine (50 microg/kg), an Na(+) channel opener, stimulated deflationary SAR activity: one maintained excitatory activity mainly during deflation and the other receptors showed a tonic discharge during both deflation and inflation. Despite the difference in deflationary SAR firing patterns after veratridine administration, flecainide treatment (6.0 mg/kg) blocked veratridine-induced deflationary SAR stimulation and also caused strong inhibition of the excitatory responses of deflationary SARs to lung deflation. Under these conditions, the average values for deflationary SAR AI were over 90%. The responses of deflationary SARs and deflationary SAR AI to lung deflation were not significantly altered by pretreatment with either 4-AP (0.7 and 2.0 mg/kg) or TEA (2.0 and 6.0 mg/kg). These results suggest that the excitatory effect of lung deflation on deflationary SAR activity is mediated by the activation of flecainide-sensitive Na(+) channels on the nerve terminals of deflationary SARs.  相似文献   
66.
Various tannins and related compounds were compared for their ability to stimulate the iodination (incorporation of radioactive iodine into an acid-insoluble fraction) of human peripheral blood monocytes. The stimulating activity of most of the monomeric and dimeric hydrolyzable tannins was generally higher than that of the trimeric and tetrameric compounds. Compounds that had dehydrohexahydroxydiphenoyl or chebuloyl groups had considerably less activity than those that had other functional groups (hexahydroxydiphenoyl, valoneoyl, dehydrodigalloyl, isodehydrodigalloyl, lactonized valoneoyl, hellinoyl, euphorbinoyl, dehydroeuphorbinoyl or woodfordinoyl group). The methylated derivative, nonacosa-O-methylcoriariin A, was essentially inactive, suggesting the requirement of a phenolic hydroxyl group. Three condensed tannins ((-)-epicatechin 3-O-gallate (ECG)-dimer, ECG-trimer and ECG-tetramer) significantly stimulated both monocyte iodination and their interleukin-1-like factor production. The results suggest the dependence of stimulation of monocyte iodination by tannins and related polyphenols on molecular weight.  相似文献   
67.
The authors investigated the relationship between morphological changes and functional changes of the stomach with ageing, especially in term of change of gastric emptying in 92 healthy subjects. We checked the difference in chronological age and the stomach age in these subjects (in order to assess these subjects). The morphological change was evaluated by extent of atrophic gastritis in endoscopical atrophic border and histological findings of biopsy specimens, and the functional change was evaluated by maximal acid output in gastric secretion. Atrophic gastritis was expanded and maximal acid output was significantly reduced with ageing. From these results we confirmed that there was no difference between the chronological age and the stomach age and the quality of these subjects was very good. Gastric emptying was investigated by the acetaminophen method. In spite of ageing, gastric emptying was almost constant in these healthy subjects.  相似文献   
68.
We describe our technique for performing direct thoracoscopic closure of a congenital partial pericardial defect, which was successfully employed in a 15-year-old boy. This is the first such report of a procedure that is noninvasive and may therefore become the treatment of choice for patients with a small congenital pericardial defect.  相似文献   
69.
Interaction of CN-100, a novel non-steroidal anti-inflammatory drug, with biopolymers were investigated. In collagen induced rat platelet aggregation, the inhibitory effect of CN-100 was almost equipotent as indomethacin (IM) but less potent than that of pranoprofen (PP). The effect of CN-100 on rat platelet aggregation induced by arachidonic acid (AA) was less potent than that of IM and PP. CN-100 inhibited rat platelet functions, serotonin release and malondialdehyde formation, induced by collagen more potently than those induced by AA. In heat-induced rat erythrocyte lysis and Ca2(+)-induced liposome aggregation, the inhibitory effect of CN-100 was less potent than IM but more than those of PP. CN-100 was inhibited with heat denaturation of BSA, and the effect was more potent than IM and PP. The metachromagy based on the binding of an azodye, HABA, to BSA was potentiated weakly by CN-100, but IM had no effect on it. CN-100 and IM increased the fluorescence of the binding of dansyl amide (site I probe) to BSA. These results support that there is considerable interaction between CN-100 and membrane protein, and this effect influences the membrane to increase its stability.  相似文献   
70.
Using 5 conscious mongrel dogs, a study was conducted to investigate the vagotomy on gastroduodenal movements. At the first operation, the electrodes and strangage force transducers were attached to the antrum and duodenum; after making an electromyogram and recording contraction waves simultaneously, a transthoracic truncal vagotomy (TV) was performed and similar recordings were done. In order to evaluate the effect of TV on antral motility as well as antroduodenal coordination, the motility of the antrum and average contraction force per time unit were measured before and after TV. Furthermore induced inhibition and propagated excitation were analyzed referring to lag cross correlations before and after TV. The results were as follows: As compared with pre-vagotomy values, the post-vagotomy measured amount of motility as well as the average contraction force were reduced. Before TV in digestive state both propagated excitation and induced inhibition could be recognized. During phase II in digestive state only propagated excitation could be demonstrated, while in phase III both were absent. After TV in digestive state propagated excitation was noted, but the propagating time was shorter than before TV. Induced inhibition could not be demonstrated any longer. Furthermore, during phases II and III in the interdigestive state both were not noted.  相似文献   
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