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91.
Previous studies showed an association between latent adenoviral infection with expression of the adenoviral E1A gene and chronic obstructive pulmonary disease (COPD). The present study focuses on how the adenoviral E1A gene could alter expression of growth factors by human bronchial epithelial (HBE) cells. The data show that connective tissue growth factor (CTGF) and transforming growth factor (TGF)-beta 1 mRNA and protein expression were upregulated in E1A-positive HBE cells. Upregulation of CTGF in this in vitro model was independent of TGF-beta secreted into the growth medium. Comparison of E1A-positive with E1A-negative HBE cells showed that both expressed cytokeratin but only E1A-positive cells expressed the mesenchymal markers vimentin and alpha-smooth muscle actin. We conclude that latent infection of epithelial cells by adenovirus E1A could contribute to airway remodeling in COPD by the viral E1A gene, inducing TGF-beta 1 and CTGF expression and shifting cells to a more mesenchymal phenotype.  相似文献   
92.
Weanling female Wistar rats were supplemented with fish oil (1 g/kg body weight) for one generation. The male offspring received the same supplementation until to adult age. Rats supplemented with coconut fat were used as reference. Some rats were inoculated subcutaneously with a suspension (2 x 10(7) cells/mL) of Walker 256 tumor. At day 3, when the tumor was palpable, rats were treated with naproxen (N) (0.1 mg/mL), clenbuterol (Cb) (0.15 mg/kg body weight), and insulin (I) (10 U/kg body weight). At day 14 after tumor inoculation, the animals were killed. Tumor was removed and weighed. Blood, liver, and skeletal muscles were also collected for measurements of metabolites and insulin. In both tumor-bearing untreated rats and tumor-bearing rats supplemented with coconut fat, tumor growth, triacylglycerol, and blood lactate levels were higher, and glycogen content of the liver, blood glucose, cholesterol and HDL-cholesterol levels were lower as compared with the non-tumor-bearing and fish oil supplemented groups. Fish oil supplementation of tumor-bearing rats led to a partial recovery of the glycogen content in the liver and a full reversion of blood glucose, lactate, cholesterol, and HDL-cholesterol levels. The treatment with N plus Cb plus I attenuated cancer cachexia and decreased tumor growth in both coconut fat and fish oil supplemented rats. In conclusion, chronic fish oil supplementation decreased tumor growth and partially recovered cachexia. This beneficial effect of fish oil supplementation was potentiated by treatment with naproxen plus clenbuterol plus insulin.  相似文献   
93.
Administration of 50 g of bisphenol A (BPA) for the first 5 days after birth resulted in a decrease in the percentage of moving sperm, and an increase in the incidence of malformed sperm, in the epididymides of mice at 10 weeks of age, although no marked changes were found in the testicular histology between BPA-treated and vehicle-treated control mice. The deteriorating effects of 50 g of BPA were ameliorated by the concurrent administration of 100 IU of retinol acetate (RA). Neonatal treatment with 0.5 g of BPA for 5 days resulted in an increase in the incidence of malformed sperm, whereas the BPA effect became more severe in mice nursed by mothers fed a vitamin A-deficient (VAD) diet only a few days before and after parturition. On the other hand, neonatal treatment with 20 g of estrogen for the first 5 days after birth resulted in an increase in the number of estrogen receptor (ER)-positive cells in the epithelium of the vas deferens, whereas only a few epithelial cells showed weak ER-positive signals in the vehicle-treated control mice at 18 days after birth. This increase, however, was suppressed by the concurrent administration of RA. Although five daily treatments with 50 g BPA led to no significant increase in the number of ER-positive cells, it may have been due to the weak estrogenic activity of BPA, as discussed. These findings clearly showed that in mice, neonatal exposure to a relatively large dose of BPA causes damage to the motility and morphology of sperm, but the BPA effect is, to some extent, inhibited by a supplement of VA, and enhanced under a VAD condition.This work was supported by Grants-in-Aid for Encouragement of Young Scientists, Scientific Research (C) and Scientific Research on Priority Areas (A) from the Ministry of Education, Science, Sports, and Culture, Japan  相似文献   
94.
The effects of dietary phytochemicals on P-glycoprotein function were investigated using human multidrug-resistant carcinoma KB-C2 cells and the fluorescent P-glycoprotein substrates daunorubicin and rhodamine 123. The effects of natural chemopreventive compounds, capsaicin found in chilli peppers, curcumin in turmeric, [6]-gingerol in ginger, resveratrol in grapes, sulforaphane in broccoli, 6-methylsulfinyl hexyl isothiocyanate (6-HITC) in Japanese horseradish wasabi, indole-3-carbinol (I3C) in cabbage, and diallyl sulfide and diallyl trisulfide in garlic, were examined. The accumulation of daunorubicin in KB-C2 cells increased in the presence of capsaicin, curcumin, [6]-gingerol, and resveratrol in a concentration-dependent manner. The accumulation of rhodamine 123 in KB-C2 cells was also increased, and the efflux of rhodamine 123 from KB-C2 cells was decreased by these phytochemicals. Sulforaphane, 6-HITC, I3C, and diallyl sulfide and diallyl trisulfide had no effect. These results suggest that dietary phytochemicals, such as capsaicin, curcumin, [6]-gingerol, and resveratrol, have inhibitory effects on P-glycoprotein and potencies to cause drug-food interactions.  相似文献   
95.
A modified version of sorbitol MacConkey medium containing cefixime and tellurite (CT-SMAC medium) was produced by adding salicin and 4-methylumbelliferyl-beta-D-galactopyranoside to CT-SMAC medium; this medium was designated CT-SSMAC medium and was used to isolate Escherichia coli O157:H7 from radish sprouts. Of 101 non-E. coli bacteria isolated from radish sprouts that produced colorless colonies similar to colonies of E. coli O157:H7 grown on CT-SMAC medium, 92 (91%) formed colonies that were red to pink or were beta-galactosidase negative and colorless on CT-SSMAC medium. On the other hand, colonies of E. coli O157:H7 strains were colorless and beta-galactosidase positive on CT-SSMAC medium. Our results suggest that CT-SSMAC medium is more selective than CT-SMAC medium for isolating E. coli O157:H7.  相似文献   
96.
Angiotensin II (Ang II) evokes a variety of hypertrophic responses such as activation of protein kinases, reprogramming of gene expressions and an increase in protein synthesis in cardiac myocytes. In this study, we examined the role of Rho family small GTP binding proteins (G proteins) in Ang II-induced cardiac hypertrophy. Ang II strongly activated extracellular signal-regulated protein kinases (ERKs) in cardiac myocytes of neonatal rats. Although Ang II-induced activation of ERKs was completely suppressed by an Ang II type 1 receptor antagonist, CV-11974, this activation was not inhibited by the pretreatment with C3 exoenzyme, which abrogates Rho functions. Overexpression of Rho GDP dissociation inhibitor (Rho-GDI), dominant negative mutants of Rac1 (D.N.Rac1), or D.N.Cdc42 had no effects on Ang II-induced activation of transfected ERK2. The promoter activity of skeletal a-actin and c-fos genes was increased by Ang II, and the increase was partly inhibited by overexpression of Rho-GDI and the pretreatment with C3 exoenzyme. Ang II increased phenylalanine incorporation into cardiac myocytes by approximately 1.4 fold as compared with control, and this increase was also significantly suppressed by the pretreatment with C3 exoenzyme. These results suggest that the Rho family small G proteins play important roles in Ang II-induced hypertrophic responses in cardiac myocytes.  相似文献   
97.
Eosinophil peroxidase (EPX) is one of a family of mammalian peroxidases that includes myeloperoxidase (MPO), lactoperoxidase (LPO), and thyroid peroxidase (TPO). Here we show that the human EPX gene maps to chromosome 17q23.1, which localizes 34 kb from the LPO and MPO genes. Our results demonstrate that the EPX, LPO, and MPO genes form a cluster on human chromosome 17.  相似文献   
98.
Myosin II molecules assemble and form filaments through their C-terminal rod region, and the dynamic filament assembly-disassembly process of nonmuscle myosin II molecules is important for cellular activities. To estimate the critical region for filament formation of vertebrate nonmuscle myosin II, we assessed the solubility of a series of truncated recombinant rod fragments of nonmuscle myosin IIB at various concentrations of NaCl. A C-terminal 248-residue rod fragment (Asp 1729-Glu 1976) was shown by its solubility behavior to retain native assembly features, and two regions within it were found to be necessary for assembly: 35 amino acid residues from Asp 1729 to Thr 1763 and 39 amino acid residues from Ala 1875 to Ala 1913, the latter containing a sequence similar to the assembly competence domain (ACD) of skeletal muscle myosin. Fragments lacking either of the two regions were soluble at any NaCl concentration. We referred to these two regions as nonmuscle myosin ACD1 (nACD1) and nACD2, respectively. In addition, we constructed an alpha-helical coiled-coil model of the rod fragment, and found that a remarkable negative charge cluster (termed N1) and a positive charge cluster (termed P2) were present within nACD1 and nACD2, respectively, besides another positive charge cluster (termed P1) in the amino-terminal vicinity of nACD2. From these results, we propose two major electrostatic interactions that are essential for filament formation of nonmuscle myosin II: the antiparallel interaction between P2 and N1 which is essential for the nucleation step and the parallel interaction between P1 and N1 which is important for the elongation step.  相似文献   
99.
In order to develop orally active CCR5 antagonists, 1-propyl- or 1-isobutyl-1-benzazepine derivatives containing a sulfoxide moiety have been designed, synthesized, and evaluated for their biological activities. Sulfoxide compounds containing a 2-pyridyl group were first investigated, which led to discovering that the presence of a methylene group between the sulfoxide moiety and 2-pyridyl group was necessary for increased inhibitory activity in a binding assay. After further chemical modification, it was found that replacement of the pyridyl group with an imidazolyl or 1,2,4-triazolyl group enhanced activity in the binding assay and that S-sulfoxide compounds were more active than R-isomers. Particularly, compounds (S)-4r, (S)-4s, and (S)-4w exhibited highly potent CCR5 antagonistic activities (IC50=1.9, 1.7, 1.6 nM, respectively) and inhibitory effects (IC50=1.0, 2.8, 7.7 nM, respectively) in the HIV-1 envelope mediated membrane fusion assay, together with good pharmacokinetic properties in rats. In addition, we established the synthesis of (S)-4r and (S)-4w by asymmetric oxidation with titanium-(S)-(-)-1,1'-bi-2-naphthol complex.  相似文献   
100.
Previously, using the Keratin5-Cre transgenic mouse model we reported that female Lgr4-conditional KO mice (Lgr4K5 KO) showed subfertility with defective stromal decidualization due to abnormal development of the uterine gland. However, the impact of the LGR4 defect on luminal epithelial cells was not investigated in the previous report. Here, we focused on the receptive state of the luminal epithelium in Lgr4K5 KO mice that received ovarian hormone treatment. In Lgr4K5 KO mice, progesterone failed to inhibit the luminal epithelial cell proliferation. Immunohistochemical and qRT-PCR analyses revealed down-regulated progesterone signaling in the uterus of Lgr4K5 KO mice. These results demonstrated that LGR4 is essential for the acquisition of endometrial receptivity through ovarian hormone signaling.  相似文献   
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