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501.
Abstract

Background and purpose: Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by inflammation and joint destruction. Excessive proliferation of fibroblast-like synoviocytes (FLS) and over-expression of angiogenic factors play a crucial role in pannus formation and joint destruction in RA. Clarification of the role of cholinergic agonists in modulation of inflammation and immune system reactions is progressively ongoing. In this study, the anti-angiogenic effect of two cholinergic agonists, nicotine and ARR17779, on human FLS, and monocytic cell lines (U937) was evaluated.

Experimental approach: The cells were cultured in DMEM supplemented with 10% FBS and treated with different doses of nicotine and ARR17779 in the presence of TNF-α, LPS, and IFN-γ. After 48?h, cell number was counted in different groups. After RNA extraction, cDNA was synthesized and the expression of VEGF and MMPs has been evaluated by real-time PCR using specific primers and probes. VEGF was assayed in U937 cell line supernatant using ELISA method.

Key results: Both nicotine and ARR17779 inhibited FLS and U937 cell proliferation. Cholinergic agonists reduced the expression of MMPs and VEGF. VEGF level in supernatant of U937 cells treated with cholinergic agonists was also reduced.

Conclusion and implications: Our results suggest that cholinergic agonists can modulate pathological conditions related to pannus formation in in-vitro conditions. Based on these results, cholinergic agonists can be considered as novel therapeutic options in RA. Further animal studies are needed before introducing these agents into clinical uses.  相似文献   
502.
The aim of the present study was to evaluate the degree of sperm DNA fragmentation in couples with idiopathic recurrent spontaneous abortion (RSA) and in those with no history of infertility or abortion. In this cohort study, 30 couples with RSA and 30 fertile couples as control group completed the demographic data questionnaires, and their semen samples were analysed according to World Health Organization (WHO) standards (September 2009–March 2010) for evaluation of sperm DNA fragmentation, using sperm chromatin dispersion (SCD) technique. The percentage of morphologically normal sperm was significantly lower in RSA patients compared with control group (51.50 ± 11.60 versus 58.00 ± 9.05, P = 0.019), but not in other parameters. Additionally, the level of abnormal DNA fragmentation in the RSA group was significantly higher than in the control group (43.3% versus 16.7%, P = 0.024). Our results indicated a negative correlation between the number of sperm with progressive motility and DNA fragmentation (r = ?0.613; P < 0.001). The sperm from men with a history of RSA had a higher incidence of DNA fragmentation and poor motility than those of the control group, indicating a possible relationship between idiopathic RSA and DNA fragmentation.  相似文献   
503.
OBJECTIVE: Human adenovirus Ad-36 causes adiposity in animal models and enhances differentiation and lipid accumulation in human and 3T3-L1 preadipocytes, which may, in part, explain the adipogenic effect of Ad-36. We determined the consequences of Ad-36 infection on leptin and glucose metabolism in fat cells. DESIGN: 3T3-L1 preadipocytes were used to determine the effect of infection by human adenoviruses Ad-36, Ad-2, Ad-9 and Ad-37 on leptin secretion and lipid accumulation. Rat primary adipocytes were used to determine the effect of Ad-36 infection on leptin secretion and glucose uptake in vitro. Furthermore, the effect of Ad-36 on expressions of leptin and selected genes of de novo lipogenesis pathway of visceral adipose tissue were compared ex vivo, between Ad-36 infected and uninfected control rats. RESULTS: Ad-36 suppressed the expression of leptin mRNA in 3T3-L1 cells by approximately 58 and 52% on days 3 and 5 post-infection, respectively. Leptin release normalized to cellular lipid content was 51% lower (P<0.002) in the Ad-36 infected 3T3-L1 cells. Lipid accumulation was significantly greater and leptin secretion was lower for the 3T3-L1 cells infected with other human adenoviruses Ad-9, Ad-36, or Ad-37. Whereas, human adenovirus Ad-2 did not influence cellular lipid accumulation or the leptin release. In rat primary adipocytes, Ad-36 reduced leptin release by about 40% in presence of 0.48 (P<0.01) or 1.6 nM insulin (P<0.05) and increased glucose uptake by 93% (P<0.001) or 18% (P<0.05) in presence of 0 or 0.48 nM insulin, respectively. Next, the adipose tissue of Ad-36 infected rats showed two to fivefold lower leptin mRNA expression, and 1.6- to 21-fold greater expressions for acetyl Co-A carboxylase-1 and 1.2- to 6.3-fold greater expressions for fatty acid synthase, key genes of de novo lipogenesis, compared to the uninfected weight and adiposity matched controls. CONCLUSION: The in vitro and ex vivo studies show that Ad-36 modulates adipocyte differentiation, leptin production and glucose metabolism. Whether such a modulation contributes to enhanced adipogenesis and consequent adiposity in Ad-36 infected animals or humans needs to be determined.  相似文献   
504.

Background

Hypoalbuminemia has been identified as a predictor of morbidity and mortality in critically ill patients. There is very little data on the significance and the prognostic value of hypoalbuminemia in patients with aneurysmal subarachnoid hemorrhage (aSAH). This study analyzed the impact of hypoalbuminemia on patient presentation, complications, and outcomes.

Methods

Records of patients admitted with aSAH were examined. Data on baseline characteristics, prevalence of delayed cerebral ischemia, and discharge outcomes were collected. Multivariable logistic regression analysis was performed to assess for associations.

Results

One-hundred and forty-two patients comprised the study cohort (mean age 54.6 ± 13.4), among which 45 (31.5 %) presented with hypoalbuminemia. No difference in baseline characteristics was noted between patients with hypoalbuminemia and those with normal serum albumin. The overall hospital mortality rate was significantly higher in patients with hypoalbuminemia, compared to those with normal albumin (28.9 % vs. 11.3 %; p = 0.04). Hypoalbuminemia was neither associated with delayed cerebral ischemia nor disability at discharge, but independently associated with in-hospital death (odds ratio: 4.26, 95 % confidence interval: 1.09–16.68; p = 0.04).

Conclusion

In patients with aSAH, early hypoalbuminemia is an independent predictor of hospital mortality but not disability at discharge.
  相似文献   
505.

Objective

Oral tongue squamous cell carcinoma (OTSCC) frequently harbors non-functional p53 and depends on G2/M checkpoint mediated by WEE1. WEE1 suppression has been identified as a promising anti-tumor strategy. This study investigated the capacity of WEE1 kinase inhibitor (MK-1775) and its underlying mechanisms in enhancing radiation responses of OTSCC cells in vitro.

Materials and methods

WEE1 kinase expression and its downstream target (CDK1) were investigated in OTSCC versus normal oral tissue. A synergistic combination of MK-1775 with radiation on OTSCC cell lines with different p53 statuses was assessed by viability assay. The radio-sensitizing effects of MK-1775 on apoptosis, cell cycle, DNA damage, and mitotic entry were also determined.

Results

Irradiation enhanced CDK1 expression in all tested cell lines, though the effect was far more pronounced in p53 mutated cell lines. MK-1775 exhibited inhibitory effects against the survival of all cell lines and enhanced their response to the radiation. These effects were strongly elicited by induction of apoptosis and lethal mitosis, but less likely by abrogation of radiation-induced G2 arrest.

Conclusion

These results demonstrate the efficacy of MK-1775 in enhancing the radiation effect on OTSCC in vitro associated with a significant apoptotic death rate, identifying WEE1 inhibitor as a potent radiosensitizer in OTSCC irrespective of p53 mutational status.  相似文献   
506.
507.
Datura spp. is a potentially poisonous plant that is widely spread and is simply accessible, which can yield poisoning with a central and peripheral anticholinergic effect. We reported cases of family poisoning caused by the herbal tea with refreshing effects that were identified as Datura spp.  相似文献   
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