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31.
目的探究阿利吉仑对高血压肾病小鼠的保护作用及其对磷脂酰肌醇激/蛋白激酶B(PI3K/Akt)信号通路和半胱氨酸天冬氨酸蛋白酶-3(Caspase-3)表达的影响。方法用微渗泵灌注血管紧张素Ⅱ制备高血压小鼠肾病模型。按照体重将小鼠随机分为6组:假手术组、模型组和低、中、高3个剂量实验组(灌胃阿利吉仑12. 5,25. 0,50. 0 mg·kg-1)与对照组(卡托普利30 mg·kg-1),每组15只;造模后给药,每日1次,连续灌胃2周。以实时定量PCR法测定肾组织中胰岛素受体底物2(Irs2)、磷脂酰肌醇激酶-3(PI3K)、蛋白激酶B(Akt) mRNA表达;以免疫印迹法测定Irs2、PI3K、Akt与Caspase-3蛋白表达情况。结果给药4周,假手术组、模型组、对照组和高剂量实验组的PI3K mRNA表达分别为1. 14±0. 21,0. 34±0. 08,1. 07±0. 23和0. 96±0. 22;这4组的Akt mRNA表达分别为1. 23±0. 27,0. 45±0. 13,1. 05±0. 16和0. 91±0. 15,模型组与假手术组比较或高剂量实验组与模型组比较,差异均有统计学意义(均P <0. 05)。这4组的小鼠肾组织Caspase-3蛋白表达水平分别为0. 29±0. 06,1. 06±0. 13,0. 31±0. 06和0. 37±0. 08,模型组与假手术组比较或高剂量实验组与模型组比较,差异均有统计学意义(均P <0. 05)。结论阿利吉仑对高血压小鼠肾具有一定的保护作用,其机制可能与激活PI3K/Akt信号通路、抑制Caspase-3表达有关。  相似文献   
32.
Over the past few years, myositis-specific autoantibodies played an increasing role in the inflammatory idiopathic myositis definition. They became the critical immunological marker for immune-mediated necrotizing myopathy diagnosis (IMNM) since the paradigm switch from histological to serological criteria.This review is focused on the key role of the anti-signal recognition particle (anti-SRP) and the anti-3-Hydroxy-3-MethylGlutaryl-Coenzyme A Reductase (anti-HMGCR) antibodies in immune-mediated necrotizing myopathy.Anti-SRP and anti-HMGCR antibodies are robust diagnostic tools in case of both the classical subacute form and the slowly progressive form of IMNM that may mimic muscular dystrophy. Anti-SRP and anti-HMGCR patients share clinical, biological and histological features with some antibody-associated specificity. Anti-SRP patients harbour more severe muscle weakness and atrophy with severe muscle damage on magnetic resonance imaging study. Approximately 10–20% of anti-SRP patients develop extramuscular symptoms, especially lung interstitial disease. Conversely, anti-HMGCR patients are often associated with statin exposure. In both cases, patients have a poor outcome with frequent relapse and the use of combined immunotherapy. Of note, various data suggest a direct pathogenic role of these antibodies reinforcing the interest in targeted therapeutic strategy.  相似文献   
33.
The consequences of once-weekly rifapentine plus isoniazid for 3 months (3HP) against latent tuberculosis infections in hemodialysis patients have not been studied before. This is the first study to evaluate the safety and tolerability of 3HP in this population and revealed a completion rate of 65.4%. The therapy was not associated with hepatotoxicity, but with high rates of adverse events (69.2%).  相似文献   
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Interferon-γ inducible protein 10 (IP-10), is a potent chemoattractant that promotes migration of monocytes and activated T-cells to inflammation foci. IP-10 is elevated in serum of patients with chronic hepatitis C virus (HCV) and tuberculosis (TB) infections, although it remains to be determined the contribution of IP-10 in restricting Mycobacterium tuberculosis (Mtb) replication. Here, we investigated the impact of IP-10 on mycobacteria replication using the ex vivo model of human whole-blood (WB) assay. In particular, we compared the levels of IP-10 upon infection with different Mtb clinical strains and species of non-tuberculous mycobacteria (NTM) and evaluated how IP-10 may contain bacterial replication. Interestingly, we observed that the inhibition of the host enzyme dipeptidyl peptidase IV (DPP-IV), which inactivates IP-10 through cleavage of two amino acids at the chemokine N-terminus, restricted mycobacterial persistence in WB, supporting the critical role of full length IP-10 in mediating an anti-Mtb response. Addition of recombinant IP-10 expressed in eukaryotic cells enhanced the anti-mycobacterial activity in WB, although no differences were observed when IP-10 containing different proportions of cleaved and non-cleaved forms of the chemokine were added. Moreover, recombinant IP-10 did not exert a direct anti-mycobacterial effect. Our results underscore the clinical relevance of IP-10 in mycobacteria pathogenesis and support the potential outcomes that may derive by targeting the IP-10/CXCR3 pathway as host directed therapies for the treatment of Mtb or NTM infections.  相似文献   
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Chloride channel 3 (CIC-3) has been suggested to be implicated in the carcinogenesis though; it still remains ill understood in hepatocarcinoma, especially in terms of clinicopathological meaning of its expression. Given this, herein, to understand the clinicopathological significance of CIC-3 expression in hepatocarcinoma, Immunohistochemistry was performed to examine the level of CIC-3, followed by statistical analysis of the correlation between expression versus clinicopathological variables, including gender, age, TNM classifications, tumor size, lymph node metastasis and overall prognosis. It was shown that positive staining of CIC-3 can be present in both hepatocarcinoma and its paired normal controls; and that CIC-3 was significantly over-expressed in hepatcarcioma on the whole relative to paired normal controls. Moreover, up-regulation of CIC-3 markedly correlated with tumor size and overall prognosis, suggesting that CIC-3 expression could predict both tumor size and overall prognosis in hepatocarcinoma.  相似文献   
38.
ObjectiveThe study objective was to identify biobehavioral variables associated with greater intake of nicotine and a tobacco carcinogen among Black light smokers who smoke 1 to 10 cigarettes per day (CPD).MethodsWe analyzed baseline data collected from 426 Black light smokers enrolled in Kick It at Swope III (KIS III), a smoking cessation trial for Black smokers. We examined differences in concentrations of tobacco biomarkers, including urinary total nicotine equivalents (TNE) and total 4-(methylnitrosamino)-1-(3)pyridyl-1-butanonol (NNAL; a human carcinogen), across gender, age, plasma nicotine metabolite ratio (NMR), CPD, and measures of tobacco dependence, including time to first cigarette (TFC), using ANOVA.ResultsTobacco biomarker levels were significantly higher among those who smoked more CPD (6–10 vs 1–5 CPD) and those with greater reported physical dependence on tobacco. Concurrently, those who smoked 1–5 CPD smoked each cigarette more intensely than those who smoked 6–10 CPD. While we found no gender differences overall, among those who smoked 1–5 CPD, women had higher NNAL levels compared to men. The rate of nicotine metabolism, measured by the nicotine metabolite ratio, was not significantly related to TNE or NNAL levels.ConclusionAmong Black Light smokers, higher cigarette consumption and greater physical dependence—but not rate of nicotine metabolism, menthol use, or socioeconomic status—were associated with greater toxicant exposure and thus a likely increased risk of tobacco-related diseases. The lack of data on light smokers, and specifically on Blacks, make this observation important given the disproportionate burden of lung cancer in this population.  相似文献   
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In contrast to rats, mouse models are nowadays generally used for the investigation of immune responses and immune-mediated diseases, there are many different strains and mouse-specific tools available, and it is easy to generate transgenic and constitutive or inducible knockout mice for any gene. Many immune markers and mechanisms have been detected in mice and have been introduced as gold standard in immunology, however, some turned out to be not unconditionally transferable to the human immune system.Rats have been used more frequently in former days but are mostly outstripped by mice due to the fact that fewer strains are available, they need more space than mice, are more expensive to maintain and breed, and it is extremely difficult to generate transgenic or ko-rats. Consequently, the choice of rat-specific diagnostic tools like antibodies is quite poor and most researchers have switched to mouse models for the investigation of immune mechanisms, while rats are still widely used for toxicology by the pharmaceutical industry. However, it should be taken into consideration that there are some immunological similarities between rats and humans that are not presented in mice. Some of them like MHC class II and Foxp3 expression by activated effector T cells we have detected during our research on the immune response of rat models of experimental autoimmune uveitis.  相似文献   
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