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91.
We describe a boy with chronic abdominal pain, nausea and vomiting, and weight loss. The imaging was compatible with Takayasu's arteritis. Chronic mesenteric ischemia was the etiology of the patient's symptoms.  相似文献   
92.
Glioma is the oneof the most prevalent primarybrain tumors. There is a variety of oxidative stresses, inflammatory pathways, apoptosis signaling, and Na+/H + exchangers (NHEs) involved in the pathophysiology of glioma. Previous studies have indicated a relationship between NHEs and some molecular pathways in glioma. NHEs, including NHE1, NHE5, and NHE9 affect apoptosis, tumor-associated macrophage inflammatory pathways, matrix metalloproteinases, cancer-cell growth, invasion, and migration of glioma. Also, inhibition of NHEs contributes to increased survival in animal models of glioma. Limited studies, however, have assessed the relationship between NHEs and molecular pathways in glioma. This review summarizes current knowledge and evidence regarding the relationship between NHEs and glioma, and the mechanisms involved.  相似文献   
93.
Parkinson's disease (PD) is one of the most prevalent neurodegenerative diseases which occur in aged people worldwide. Given that a sequence of cellular and molecular mechanisms, including oxidative stresses, apoptosis, inflammatory pathways, microglia, astrocyte activation, and aquaporin 4 (AQP4) are associated with initiation and the progression of PD. AQP4 may affect various pathways (i.e., α-synuclein, inflammatory pathways, and microglia and astrocyte activation). Few reports have evaluated the relationship between AQP4 and PD-related cellular and molecular pathways. Here, for the first time, we highlighted the relationship between AQP4 and molecular mechanisms involved in PD pathogenesis.  相似文献   
94.
95.
Curcumin, a natural polyphenolic and yellow pigment obtained from the spice turmeric, has strong antioxidative, anti-inflammatory, and antibacterial properties. Due to these properties, curcumin has been used as a remedy for the prevention and treatment of skin aging and disorders such as psoriasis, infection, acne, skin inflammation, and skin cancer. Curcumin has protective effects against skin damage caused by chronic ultraviolet B radiation. One of the challenges in maximizing the therapeutic potential of curcumin is its low bioavailability, limited aqueous solubility, and chemical instability. In this regard, the present review is focused on recent studies concerning the use of curcumin for the treatment of skin diseases, as well as offering new and efficient strategies to optimize its pharmacokinetic profile and increase its bioavailability.  相似文献   
96.
Pancreatic cancer has a high mortality rate due to the absence of early symptoms and subsequent late diagnosis; additionally, pancreatic cancer has a high resistance to radio- and chemotherapy. Multiple inflammatory pathways are involved in the pathophysiology of pancreatic cancer. Melatonin an indoleamine produced in the pineal gland mediated and receptor-independent action is the pancreas and other where has both receptors. Melatonin is a potent antioxidant and tissue protector against inflammation and oxidative stress. In vivo and in vitro studies have shown that melatonin supplementation is an appropriate therapeutic approach for pancreatic cancer. Melatonin may be an effective apoptosis inducer in cancer cells through regulation of a large number of molecular pathways including oxidative stress, heat shock proteins, and vascular endothelial growth factor. Limited clinical studies, however, have evaluated the role of melatonin in pancreatic cancer. This review summarizes what is known regarding the effects of melatonin on pancreatic cancer and the mechanisms involved.  相似文献   
97.
Purified oleuropein from olive leaf extract has been shown to have antioxidant effects in our recent studies. Thus, the aim of this study was to assess the antioxidant abilities of oleuropein in comparison with ranitidine in ethanol-induced gastric damages via evaluation of ulcer index inhibition, antioxidant enzyme activities, and lipid peroxidation level. Fifty-six adult male Sprague?CDawley rats were divided into seven equal groups as follows: control group, ethanol group (absolute ethanol 1?ml/rat), oleuropein group (12?mg/kg), and oleuropein (6, 12, and 18?mg/kg) plus ethanol groups, as well as ranitidine (50?mg/kg) plus ethanol group. Pretreatment with oleuropein (12 and 18?mg/kg) significantly increased the ulcer index inhibition (percent), in comparison with oleuropein (6?mg/kg). Glutathione peroxidase (GPx) activity was significantly lower in the ethanol group when compared with the other groups whereas, treatment of rats with oleuropein (12?mg/kg) significantly increased glutathione content in gastric tissue when compared with the other groups, and lipid peroxidation was significantly reduced in the oleuropein- (12 and 18?mg/kg) and ranitidine-treated animals. Superoxide dismutase (SOD) and catalase (CAT) activities were both much higher in oleuropein-treated rats than the ethanol group, and although there was a moderate increase in SOD and CAT activities in ranitidine-treated rats, the differences were not significant. These findings suggest that oleuropein has beneficial antioxidant properties against ethanol-induced gastric damages in the rat. Therefore, it seems that a combination regimen including both antioxidant and antisecretory drugs may be beneficial in prevention of ethanol-mediated gastric mucosal damages.  相似文献   
98.

Background

Meta-analyses conducted via the Cochrane Collaboration adhere to strict methodological and reporting standards aiming to minimize bias, maximize transparency/reproducibility, and improve the accuracy of summarized data. Whether this results in differences in the results reported by meta-analyses on the same topic conducted outside the Cochrane Collaboration is an open question.

Methods

We conducted a matched-pair analysis with individual meta-analyses as the unit of analysis, comparing Cochrane and non-Cochrane reviews. Using meta-analyses from the cardiovascular literature, we identified pairs that matched on intervention and outcome. The pairs were contrasted in terms of how frequently results disagreed between the Cochrane and non-Cochrane reviews, whether effect sizes and statistical precision differed systematically, and how these differences related to the frequency of secondary citations of those reviews.

Results

Our search yielded 40 matched pairs of reviews. The two sets were similar in terms of which was first to publication, how many studies were included, and average sample sizes. The paired reviews included a total of 344 individual clinical trials: 111 (32.3%) studies were included only in a Cochrane review, 104 (30.2%) only in a non-Cochrane review, and 129 (37.5%) in both. Stated another way, 62.5% of studies were only included in one or the other meta-analytic literature. Overall, 37.5% of pairs had discrepant results. The most common involved shifts in the width of 95% confidence intervals that would yield a different statistical interpretation of the significance of results (7 pairs). Additionally, 20% differed in the direction of the summary effect size (5 pairs) or reported greater than a 2-fold difference in its magnitude (3 pairs). Non-Cochrane reviews reported significantly higher effect sizes (P< 0.001) and lower precision (P<0.001) than matched Cochrane reviews. Reviews reporting an effect size at least 2-fold greater than their matched pair were cited more frequently.

Conclusion

Though results between topic-matched Cochrane and non-Cochrane reviews were quite similar, discrepant results were frequent, and the overlap of included studies was surprisingly low. Non-Cochrane reviews report larger effect sizes with lower precision than Cochrane reviews, indicating systematic differences, likely reflective of methodology, between the two types of reviews that could generate different interpretations of the interventions under question.  相似文献   
99.
Aberrant DNA methylation is a feature of human cancer affecting gene expression and tumor phenotype. Here, we quantified promoter methylation of candidate genes and global methylation in 44 small intestinal-neuroendocrine tumors (SI-NETs) from 33 patients by pyrosequencing. Findings were compared with gene expression, patient outcome and known tumor copy number alterations. Promoter methylation was observed for WIF1, RASSF1A, CTNNB1, CXCL14, NKX2–3, P16, LAMA1, and CDH1. By contrast APC, CDH3, HIC1, P14, SMAD2, and SMAD4 only had low levels of methylation. WIF1 methylation was significantly increased (P = 0.001) and WIF1 expression was reduced in SI-NETs vs. normal references (P = 0.003). WIF1, NKX2–3, and CXCL14 expression was reduced in metastases vs. primary tumors (P < 0.02). Low expression of RASSF1A and P16 were associated with poor overall survival (P = 0.045 and P = 0.011, respectively). Global methylation determined by pyrosequencing of LINE1 repeats was reduced in tumors vs. normal references, and was associated with loss in chromosome 18. The tumors fell into three clusters with enrichment of WIF1 methylation and LINE1 hypomethylation in Cluster I and RASSF1A and CTNNB1 methylation and loss in 16q in Cluster II. In Cluster III, these alterations were low-abundant and NKX2-3 methylation was low. Similar analyses in the SI-NET cell lines HC45 and CNDT2 showed methylation for CDH1 and WIF1 and/or P16, CXCL14, NKX2-3, LAMA1, and CTNNB1. Treatment with the demethylating agent 5-azacytidine reduced DNA methylation and increased expression of these genes in vitro. In conclusion, promoter methylation of tumor suppressor genes is associated with suppressed gene expression and DNA copy number alterations in SI-NETs, and may be restored in vitro.  相似文献   
100.
Many of CNS diseases can lead to a great quantity of release of glutamate and the extreme glutamate induces neuronal cell damage and death. Here, we wanted to investigate the effects of Cymbopogon citratus essential oil and Ferula assa-foetida extracts treatment on glutamate-induced cell damage in a primary culture of rat cerebellar granule neurons. Cerebellums were collected from 7-d rat brains and cerebellar granule neurons were obtained after 8-d culture. CGN cells were treated with C. citratus essential oil and F. assa-foetida extracts at concentration of 100 μg/ml before, after, and during exposure to 30 μM glutamate. The cellular viability was evaluated by 3-(4, 5-dimethytthiazol-2-yl)-2, 5-diphenyltetrazoliumbromide (MTT) staining. The flow cytometry assay was used to examine cell cycle and apoptosis. MTT assay showed a glutamate-induced reduction in cellular viability while treatment with C. citratus essential oil and F. assa-foetida extracts before, during, and after exposure to glutamate was increased. Flow cytometric analysis indicated that F. assa-foetida extracts treatment significantly (p?<?0.001) attenuated glutamate-induced apoptotic/necrotic cell death and the necrotic rate was decreased by C. citratus essential oil treatment compared to glutamate group, significantly (p?<?0.001). The results show that C. citratus essential oil and F. assa-foetida extracts display neuroprotective effects in glutamate-induced neurotoxicity. These extracts exert antiapoptotic activity in cerebellar granule neurons due to cell cycle arrest in G0G1 phase, which explain the beneficial effects of C. citratus essential oil and F. assa-foetida extracts as therapies for neurologic disorders.  相似文献   
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