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41.
Wang H  Li J  Yu L  Zhao Y  Ding W 《Life sciences》2004,74(13):1645-1658
Nephrotic syndrome has long been treated in China with two herbs, Astragalus mongholicus and Angelica sinensis, which may have antifibrotic effects. METHODS: Rats with chronic puromycin-induced nephrosis were treated with Astragalus and Angelica 3 mL/d (n = 7) or enalapril 10 mg/kg/d (n = 7). Normal control rats (n = 7) received saline rather than puromycin, and an untreated control group (n = 7) received puromycin but no treatment. After 12 weeks, stained sections of the glomerulus and tubulointerstitium were evaluated for injury. Immunohistochemistry staining measured extracellular matrix components, transforming growth factor-beta1 (TGFbeta1), osteopontin, ED-1-positive cells, and alpha-actin. TGFbeta1 mRNA was assessed by in situ hybridization. Renin, ACE activity, angiotensin, and aldosterone were measured by radioimmunoassay or colorimetry. In the untreated rats, chronic renal injury progressed to marked fibrosis at 12 weeks. Astragalus and Angelica significantly reduced deterioration of renal function and histologic damage. Expressions of type III and IV collagen, fibronectin, and laminin also decreased significantly. This anti-fibrotic effect was similar to that of enalapril. The herbs had no effect on the renin-angiotensin system but did reduce the number of ED-1-positive, and alpha-actin positive cells and expression of osteopontin compared to untreated controls. The combination of Astragalus and Angelica retarded the progression of renal fibrosis and deterioration of renal function with comparable effects of enalapril. These effects were not caused by blocking the intrarenal renin-angiotensin system, but associated with suppression of the overexpression of TGFbeta1 and osteopontin, reduction of infiltrating macrophages, and less activation of renal intrinsic cells [corrected].  相似文献   
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C-type lectins are pattern-recognition proteins which are functionally important for pathogen recognition and immune regulation in vertebrates and invertebrates. In this study, a lectin cDNA named as Es-Lectin was cloned and characterized from the Chinese mitten crab, Eriocheir sinensis. The full-length sequence of this Es-Lectin cDNA was 651 bp, including an open reading frame of 483 bp encoding 160 amino acids. The predicted molecular weight of the Es-Lectin was 11.8 kDa. A typical signal peptide of 21 amino acids was deduced at the N-terminus of the predicted protein. This Es-Lectin belongs to a C-type lectin and contains six cysteines, a conserved EPN motif (Glu-Pro-Asn) and an imperfect WND (Trp-Asn-Asp) motif (FND, Phe-Asn-Asp). This Es-Lectin had 55% and 32% identity with other two C-type lectins in E. sinensis, and 29-36% homology with decapods. Although the Es-Lectin was also expressed in gill, hepatopancreas, intestine, muscle and stomach, its expression in haemocytes was the greatest. The expression of Es-Lectins in haemocytes increased at 1.5 h after the Aeromonas hydrophila challenge. After a slight decrease, the Es-Lectin expression in haemocytes significantly increased at 48 h post-challenge. The diverse distribution of Es-Lectin and its enhancement by bacterial challenge indicate that C-type lectins are important in the innate immune response to bacterial infection, and can be activated for innate immune response in crab at the initial stage after pathogen infection.  相似文献   
43.
The single-strand origin (SSO) of the rolling-circle (RC), broad-host-range lactococcal plasmid pWVO1 was functionally characterized. The activity of this SSO in the conversion of single-stranded DNA to double-stranded DNA was tested both in vivo and in vitro. In addition, the effect of this SSO on plasmid maintenance was determined. The functional pWVO1 SSO comprises a 250 by region, containing two inverted repeats (IRs). The activity of each IR was tested, separately and in combination, in a plasmid derivative that was otherwise completely devoid of structures that might function as SSO. One of the IRs (IR 1) showed some homology with other previously described SSOs of the SSOA type, as well as with the conversion signal of the Escherichia coli phage X174. This IR was shown to have a partial, RNA polymerise-independent activity in complementary strand synthesis, both in vivo and in vitro. The second IR, which had no activity of its own, was required for full SSO activity, both in vivo and in vitro. The conversion of single-stranded DNA to the double-stranded form by the complete SSO was only partly sensitive to inhibition by rifampicin, indicating the existence of an RNA polymerase-independent pathway for this event. The results suggest that the pWVO1 SSO can be activated by two different routes: an RNA polymerise-dependent one (requiring the entire SSO), and an RNA polymerase-independent one (requiring only IR I).  相似文献   
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In this study, we characterized the intratumoral expression of IL-17 and CD8(+) TILs in gastric adenocarcinoma patients after resection and determined the correlation between the survival probability of gastric adenocarcinoma patients and the expression of IL-17 in tumor. Expression of IL-17 and CD8 was assessed by immunohistochemistry, and the prognostic effects of intratumoral IL-17 expression and CD8(+) TILs were evaluated by Cox regression and Kaplan-Meier analysis. Immunohistochemical detection revealed the presence of IL-17 and CD8(+) cells in gastric adenocarcinoma tissue samples (90.6%, 174 out of 192 patients and 96.9%, 186 out of 192 patients, respectively). We have also found that intratumoral IL-17 expression was significantly correlated with age (p=0.004) and that the number of CD8(+)TILs was significantly correlated with UICC staging (p=0.012) and the depth of tumor invasion (p=0.022). The five-year overall survival probability among patients intratumorally expressing higher levels of IL-17 was significantly better than those expressing lower levels of IL-17 (p=0.036). Multivariate Cox proportional hazard analyses revealed that intratumoral IL-17 expression (HR: 0.521; 95% CI: 0.329-0.823; p=0.005) was an independent factor affecting the five-year overall survival probability. We conclude that low levels of intratumoral IL-17 expression may indicate poor prognosis in gastric adenocarcinoma patients.  相似文献   
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赵章武  曹梅讯 《昆虫学报》1998,41(1):108-112
激素对亚洲玉米螟幼虫滞育的影响*赵章武**曹梅讯(中国科学院上海昆虫研究所上海200025)亚洲玉米螟Ostriniafurnacalis是我国乃至亚洲地区的重要农业害虫之一。它具有兼性滞育的特点,年发生1~7代,以末龄老熟滞育幼虫越冬。来年春天终止...  相似文献   
50.
A PEG-based, folate mediated, active tumor targeting drug delivery system using DOX-hyd-PEG-FA nanoparticles (NPs) were prepared. DOX-hyd-PEG-FA NPs showed a significantly faster DOX release in pH 5.0 medium than in pH 7.4 medium. Compared with DOX-hyd-PEG NPs, DOX-hyd-PEG-FA NPs increased the intracellular accumulation of DOX and showed a DOX translocation from lysosomes to nucleus. The cytotoxicity of DOX-hyd-PEG-FA NPs on KB cells was much higher than that of free DOX, DOX-ami-PEG-FA NPs and DOX-hyd-PEG NPs. The cytotoxicity of DOX-hyd-PEG-FA NPs on KB cells was attenuated in the presence of exogenous folic acid. The IC50 of DOX-hyd-PEG-FA NPs and DOX-hyd-PEG NPs on A549 cells showed no significant difference. After DOX-hyd-PEG-FA NPs were intravenously administered, the amount of DOX distributed in tumor tissue was significantly increased, while the amount of DOX distributed in heart was greatly decreased as compared with free DOX. Compared with free DOX, NPs yielded improved survival rate, prolonged life span, delayed tumor growth and reduced the cardiotoxicity in tumor bearing mice model. These results indicated that the acid sensitivity, passive and active tumor targeting abilities were likely to act synergistically to enhance the drug delivery efficiency of DOX-hyd-PEG-FA NPs. Therefore, DOX-hyd-PEG-FA NPs are a promising drug delivery system for targeted cancer therapy.  相似文献   
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