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71.
Wan R  Mo Y  Chien S  Li Y  Li Y  Tollerud DJ  Zhang Q 《Nanotoxicology》2011,5(4):568-582
Nickel is an important economic commodity, but it can cause skin sensitization and may cause lung diseases such as lung fibrosis, pneumonitis, bronchial asthma and lung cancer. With development of nanotechnology, nano-sized nickel (Nano-Ni) and nano-sized titanium dioxide (Nano-TiO?) particles have been developed and produced for many years with new formulations and surface properties to meet novel demands. Our previous studies have shown that Nano-Ni instilled into rat lungs caused a greater inflammatory response as compared with standard-sized nickel (5 μm) at equivalent mass concentrations. Nano-Ni caused a persistent high level of inflammation in lungs even at low doses. Recently, several studies have shown that nanoparticles can translocate from the lungs to the circulatory system. To evaluate the potential systemic effects of metal nanoparticles, we compared the effects of Nano-Ni and Nano-TiO? on matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9) gene expression and activity. Our results showed that exposure of human monocyte U937 to Nano-Ni caused dose- and time- dependent increase in MMP-2 and MMP-9 mRNA expression and pro-MMP-2 and pro-MMP-9 activity, but Nano-TiO? did not. Nano-Ni also caused dose- and time- related increase in tissue inhibitor of metalloproteinases 1 (TIMP-1), but Nano-TiO? did not. To determine the potential mechanisms involved, we measured the expression of hypoxia inducible factor 1α (HIF-1α) in U937 cells exposed to Nano-Ni and Nano-TiO?. Our results showed that exposure to Nano-Ni caused HIF-1α accumulation in the nucleus. Furthermore, pre-treatment of U937 cells with heat shock protein 90 (Hsp90) inhibitor, 17-(Allylamino)-17-demethoxygeldanamycin (17-AAG), prior to exposure to Nano-Ni significantly abolished Nano-Ni-induced MMP-2 and MMP-9 mRNA upregulation and increased pro-MMP-2 and pro-MMP-9 activity. Our results suggest that HIF-1α accumulation may be involved in the increased MMP-2 and MMP-9 production in U937 cells exposed to Nano-Ni.  相似文献   
72.
The aim of this study was to develop a placebo model for bipolar disorder to help optimize clinical trial designs for studies targeting manic episodes in bipolar disorder. A bipolar disease database was built based on individual longitudinal data collected from over 3,000 patients in 11 clinical trials for 5 approved bipolar drugs. An empirical placebo effect model with an exponential decay process plus a linear progression process was developed to quantify the time course of the Young Mania Rating Scale total score based on only placebo data from the database. In order to describe the dropout pattern during the trials, a parametric survival model was developed and the Weibull distribution was identified to be the best distribution to describe the data. Based on the likelihood ratio test, it was found that patients with higher baseline score, slower disease improvement and more rapid disease progression tended to dropout earlier, and the trial features such as trial starting year and trial site were also significant covariates for dropout. A combination of the placebo effect model and the dropout model was applied to simulate new clinical trials through Monte-Carlo simulation. Both the placebo effect model and dropout model described the observed data reasonably well based on various diagnostic plots. The joint placebo response and dropout models can serve as a tool to simulate the most likely level of placebo response with the expected dropout pattern to help design a new clinical trial.  相似文献   
73.
74.
Infection by the hepatitis B virus (HBV) is one of the main etiologies of hepatocellular carcinoma (HCC). During chronic infection, HBV DNA can integrate into the human genome, and this has been postulated as a possible mechanism of HBV‐induced HCC. In this study we used 2199 HBV integration sites from Dr.VIS v2.0 and mapped them to the human genome (hg19) to obtain viral integration sites (VIS) related to protein‐coding and non‐protein‐coding genes. In total, we found 1,377 and 767 VIS within close proximity to protein coding genes and noncoding genes, respectively. Genes affected more than two times included 23.1% of protein‐coding genes and 24.7% of long noncoding RNAs (lncRNA). Only 4.8% of VIS were shared between HCC and non‐tumor tissues. HBV integrations were more common in chromosomes 5, 8, 10, and 19 in HCC tissue and chromosomes 1 and 2 in non‐tumorous tissue. The number of integration sites on each chromosome correlated with the number of fragile sites in non‐tumorous tissue but not in HCC tissue. Functional enrichment analysis of the protein‐coding genes containing or in close proximity to HBV integration sites in HCC tissue showed an enrichment of cancer related gene ontology terms. Additionally, the most frequently associated lncRNA genes were related to telomere maintenance, protein modification processes, and chromosome localization. Thus, HBV may have preferred integration sites in the human genome that serve a critical role in HCC development. These results show that HCC treatment may benefit from the development of next generation anti‐viral therapies.  相似文献   
75.
Phytochemical study on a methanol-soluble extract of the leaves of persimmon (Diospyros kaki) resulted in the isolation of two new ursane-type triterpenoids, 3alpha,19alpha-dihydroxyurs-12,20(30)-dien-24,28-dioic acid (1) and 3alpha,19alpha-dihydroxyurs-12-en-24,28-dioic acid (2), together with 12 known ursane- and oleanane-type triterpenoids (3-14). Triterpenoids with a 3beta-hydroxy group were found to inhibit protein tyrosine phosphatase 1B (PTP1B) activity, with IC50 values ranging from 3.1+/-0.2 to 18.8+/-1.3 microM, whereas those with a 3alpha-hydroxy moiety were not active.  相似文献   
76.
Immunomodulatory and anti-SARS activities of Houttuynia cordata   总被引:1,自引:0,他引:1  
BACKGROUND: Severe acute respiratory syndrome (SARS) is a life-threatening form of pneumonia caused by SARS coronavirus (SARS-CoV). From late 2002 to mid 2003, it infected more than 8000 people worldwide, of which a majority of cases were found in China. Owing to the absence of definitive therapeutic Western medicines, Houttuynia cordata Thunb. (Saururaceae)(HC) was shortlisted by Chinese scientists to tackle SARS problem as it is conventionally used to treat pneumonia. AIM OF THE STUDY: The present study aimed to explore the SARS-preventing mechanisms of HC in the immunological and anti-viral aspects. RESULTS: Results showed that HC water extract could stimulate the proliferation of mouse splenic lymphocytes significantly and dose-dependently. By flow cytometry, it was revealed that HC increased the proportion of CD4(+) and CD8(+) T cells. Moreover, it caused a significant increase in the secretion of IL-2 and IL-10 by mouse splenic lymphocytes. In the anti-viral aspect, HC exhibited significant inhibitory effects on SARS-CoV 3C-like protease (3CL(pro)) and RNA-dependent RNA polymerase (RdRp). On the other hand, oral acute toxicity test demonstrated that HC was non-toxic to laboratory animals following oral administration at 16 g/kg. CONCLUSION: The results of this study provided scientific data to support the efficient and safe use of HC to combat SARS.  相似文献   
77.
OBJECTIVE: Estrogen and estrogen receptors are known to play important roles in the pathophysiology of pelvic organ prolapse (POP). We investigated whether estrogen receptor beta (ERbeta) gene polymorphisms were associated with POP by conducting a case-control association study in 69 women with POP and 141 women without POP. STUDY DESIGN: Genotypes of the ERbeta gene polymorphisms (rs2987983, rs1271572, rs944459, rs1256049, and rs1255998) were determined by polymerase chain reaction, followed by restriction fragment length polymorphism analysis. Haplotyping analysis was used to determine the relationship among five polymorphisms in the ERbeta gene and POP. RESULTS: There was no significant difference between women with and those without POP in the distribution of any of the genotypes evaluated. In haplotype frequency estimation analysis, haplotype CGCGC was more prevalent in women with POP (16.7%) than in women without POP (8.9%) (p=0.011). Using multivariable logistic regression, age, parity and haplotype CGCGC were significantly associated with POP. CONCLUSION: Although the sample size of women with POP studied is small, the present study shows that ERbeta gene haplotype may be associated with POP.  相似文献   
78.
AIM: To compare the success, clinical outcomes, and maternal and neonatal complications between the Kiwi Omnicup and the Malmstrom metal cup in vacuum assisted delivery. METHODS: This was a prospective randomized comparative trial. Women who required vacuum assisted vaginal delivery were randomized into the Kiwi Omnicup (KO) group and the Malmstrom metal cup (MM) group. The vacuum assisted deliveries were conducted according to hospital protocol. Details of the procedure and delivery outcomes including success and complications were analyzed. RESULTS: One hundred and sixty-four women were recruited - 85 were assigned to vacuum assisted delivery using the KO and 79 the MM. One hundred percent delivery success was achieved with no significant differences between the two instruments in terms of maternal morbidity (P = 0.66). Six women in the MM group sustained post delivery complications in comparison to five in the KO group. Three babies were diagnosed with birth asphyxia in each group. More babies in the MM group were admitted to the Neonatal Intensive Care Unit (NICU) (10 babies versus 5 babies) and suffered complications (14 versus 12 babies), compared to the KO group, although the difference was not statistically significant. There were no intrapartum or neonatal deaths and of those admitted to the NICU, all were discharged within a week without any serious consequences. CONCLUSION: Kiwi Omnicup is an effective alternative to the currently available Malmstrom metal cup for vacuum assisted delivery with no increase in maternal or neonatal morbidity or mortality.  相似文献   
79.
Improvementofheat-tolerancebytrainingI.Evaluationofeffectsoflong-distancerunningandmarchtrainingonheat-toleranceQiuRenzhi(邱仞之...  相似文献   
80.
目的:探讨双入路小切口坏死组织清除术联合持续灌注引流治疗感染性坏死性胰腺炎(INP)的临床疗效。方法:采用回顾性描述性研究方法。收集2016年4月至2019年7月陆军军医大学大坪医院收治的20例INP病人的临床资料;男11例,女9例;年龄为(42 ±9)岁。20例病人均行双入路小切口坏死组织清除术,联合术后...  相似文献   
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