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91.
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A group of 11 medicinal plants, including Lavandula pubescens, Trigonella foenugricium, Salsola schweinforthi, Calligonum comosum, Silene succulenta, Silene villosa, Bogonvillea glabra, Cakile maritime, Gomphrene celesoids, Mirabilis jalaba, and Silene nocturna growing in Egypt, were extracted and examined for their immunomodulatory and antioxidant activities. RAW 264.7 cells were recruited to investigate the immunomodulatory effect through multiple parameters analysis. First, the proliferation index of macrophages cells was evaluated revealing that Trigonella foenugricium, Silene succulenta and Silene villosa have a significant cytotoxic effect on RAW cells. Interestingly, we observed enhancement of macrophages phagocytic function of by all extracts except Cakile maritime, Gomphrena celosioides and Silene nocturna. Afterwards, macrophages were challenged by incubation with LPS and the effect of various extracts on inflammatory responses was investigated; the generation of NO from activated macrophage was substantially suppressed by 7 extracts namely, Trigonella foenugricium, Calligonum comosum, Silene succulenta, Bougainvillea glabra, Mirabilis jalaba, Gomphrena celosioides and Silene nocturna. TNF-α was decreased by percentage range from 3.8 to 85.8% and Trigonella foenugricium extract showed the highest inhibition of TNF-α release. All extracts except Trigonella foenugricium, Salsola schweinforthi, Silene succulenta and Mirabilis jalaba significantly inhibited COX-2 production from stimulated macrophage. Moreover, evaluating the potential antioxidant activity of these extracts showed that Trigonella foenugricium, Salsola schweinforthi, Calligonum comosum, Bogonvillea glabra and Mirabilis jalaba exhibited some antioxidant activities. Taken together, our results suggest that some of these extracts may have a considerable antinflammatory and antioxidant effects and may be a potential therapeutic choice in the treatment of inflammatory diseases.  相似文献   
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OBJECTIVE: To evaluate the effect of N-acetyl-cysteine (NAC), a mucolytic drug with insulin sensitizing properties, as an adjuvant therapy in subjects with polycystic ovary syndrome (PCOS) resistant to clomiphene citrate (CC). DESIGN: Placebo-controlled, double-blind randomized trial. SETTING: University-based hospital and private infertility practice. PATIENT(S): One hundred fifty women diagnosed with CC-resistant PCOS, aged 18-39 years undergoing therapy for infertility were included. INTERVENTION(S): The patients were assigned randomly to receive either NAC 1.2 g/d (group I) or placebo (group II) with CC 100 mg/d for 5 days starting at day 3 of the cycle. MAIN OUTCOME MEASURE(S): Ovulation rate and pregnancy rate (PR). RESULT(S): Combination of CC and NAC significantly increased both ovulation rate and PR in women with CC-resistant PCOS (49.3% vs. 1.3% and 21.3% vs. 0%, respectively). No cases of ovarian hyperstimulation syndrome (OHSS) were reported in the NAC group; two cases of miscarriage (12.5%) were reported. CONCLUSION(S): The NAC as an adjuvant to CC was more effective than placebo for CC-resistant patients with PCOS. It is safe and well tolerated.  相似文献   
95.
Levetiracetam (LEV) is an approved drug for the treatment of some epileptic disorders. With few and controversial reports addressing its possible pharmacodynamic interactions, the current study aimed at studying the effect of LEV on isolated rat duodenal strips to enlighten its possible intestinal adverse effects using the isolated smooth muscle strips of rat duodenum. LEV showed a dose‐dependent inhibition in KCl (80 mm )‐induced contractions in normal Tyrode's solution. Moreover, preincubation with LEV (3 mm ) in K+‐rich/Ca2+‐free medium led to a significant decrease in the maximum contractions (Emax) coupled to a right shift of the cumulative CaCl2 concentration curves implying a possible Ca2+ channel blocking potential. In addition, LEV exhibited a typical noncompetitive inhibition in the cumulative carbachol concentration curves evidenced as a decrease in Emax without the alteration of EC50, thus eliminating any possible role of the muscarinic receptors in the relaxant effect. To rule out other possible relaxant mechanisms, tests were conveyed in Tyrode's solution containing either 100 μm l ‐NAME or 10 μm glimepiride to test the possible relaxant roles exhibited by nitric oxide (NO) and KATP channel opening, respectively. None of the tested pathways was involved in LEV‐mediated relaxation. Taken altogether, the results of the current study entail that LEV might exert a relaxant effect on intestinal smooth muscles through blocking L‐type voltage‐operated calcium channels, but not involving either NO release or KATP channel opening.  相似文献   
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Background Although clinical and experimental studies have demonstrated a correlation between obstructive jaundice and the development of sepsis, the mechanism has not been fully elucidated. Purpose The aim of this study was to investigate the influence of biliary obstruction on bacterial translocation as a possible source of infection in cases of obstructive jaundice. Material and Methods Two groups of 12 Wistar rats were examined: rats subjected to common bile duct (CBD) ligation (group A) and rats subjected to a sham operation (group B). After 7 days, blood samples were taken and liver, spleen, and mesenteric lymph nodes (MLNs) from the ileocecal area were removed, divided into small pieces, and cultured. Quantitative culture results were determined by the number of colony-forming units (CFU) per milliliter of homogenate. Bacterial translocation was defined as the presence of a positive culture of MLNs, blood, liver, and/or spleen. Samples for histopathological examination were taken from the mucosa of the ileum and the colon and evaluated for inflammatory and destructive changes. Results There was no evidence of bacterial translocation to MLNs, blood, spleen, or liver detected in any of the 12 sham-operated control rats. In contrast, bacterial translocation was demonstrated in 8 of the 12 CBD-ligated rats (P < 0.01). In all eight cases in which translocation occurred, Escherichia coli were cultured from the MLNs. There were no histological changes in the mucosal samples of the control animals. In the CBD-ligated rats, hyperemia, vacuolization, reduction of goblet cells, decreased mitotic activity, and infiltration by lymphocytes and polymorphonuclear leukocytes (PMNLs) were detected. Cases in which translocation occurred were significantly associated with decreased mitotic activity in the colon (r = −0.5, P < 0.01) and higher infiltration by PMNLs in the ileum (r = −0.62, P < 0.05). Conclusion Obstructive jaundice in a rat model predisposes to bacterial translocation. This suggests a mechanism whereby jaundiced patients are susceptible to septic complication.  相似文献   
98.
Phenylethanoid glycosides (PhGs) are generally water-soluble phenolic compounds that occur in many medicinal plants. Until June 2020, more than 572 PhGs have been isolated and identified. PhGs possess antibacterial, anticancer, antidiabetic, anti-inflammatory, antiobesity, antioxidant, antiviral, and neuroprotective properties. Despite these promising benefits, PhGs have failed to fulfill their therapeutic applications due to their poor bioavailability. The attempts to understand their metabolic pathways to improve their bioavailability are investigated. In this review article, we will first summarize the number of PhGs compounds which is not accurate in the literature. The latest information on the biological activities, structure–activity relationships, mechanisms, and especially the clinical applications of PhGs will be reviewed. The bioavailability of PhGs will be summarized and factors leading to the low bioavailability will be analyzed. Recent advances in methods such as bioenhancers and nanotechnology to improve the bioavailability of PhGs are also summarized. The existing scientific gaps of PhGs in knowledge are also discussed, highlighting research directions in the future.  相似文献   
99.
Hepatocellular carcinoma (HCC) is a major health problem worldwide. Moreover, the liver cancer field is evolving rapidly, with early diagnosis, new therapies, and a better understanding of HCC’s biology and development. Accurate staging is important for determining prognosis and selecting the most appropriate treatment for each patient. Surgical intervention remains the most effective treatment for HCC and is the only potentially curative modality. However, in HCC patients, overall survival is also independently affected by underlying liver disease and cirrhosis, which in turn affect the applicability and efficacy of treatment. Although several staging classification and prognostic scoring systems have been proposed for determining the stage and prognosis of HCC, no consensus exists on the best classification method. The most common staging classification systems include tumor-node-metastasis stage, Okuda staging, Cancer of the Liver Italian Program score, Barcelona Clinic Liver Cancer staging classification, the French, the Chinese University Prognostic Index, Japanese Integrated Scoring, and the Tokyo score. Radiologists should be aware of the different staging classification systems for HCC and familiar with the system relevant to their respective referring clinicians, as it will provide pertinent radiological evaluation for multidisciplinary management.  相似文献   
100.
Qiu L  Lai R  Lin Q  Lau E  Thomazy DM  Calame D  Ford RJ  Kwak LW  Kirken RA  Amin HM 《Blood》2006,108(7):2407-2415
The aberrant fusion protein NPM-ALK plays an important pathogenetic role in ALK+ anaplastic large-cell lymphoma (ALCL). We previously demonstrated that Jak3 potentiates the activity of NPM-ALK. Jak3 activation is restricted to interleukins that recruit the common gamma chain (gammac) receptor, including IL-9. NPM-ALK was previously shown to promote widespread lymphomas in IL-9 transgenic mice by unknown mechanisms. We hypothesized that IL-9 plays an important role in ALK+ ALCL via Jak3 activation. Our studies demonstrate the expression of IL-9Ralpha and IL-9 in 3 ALK+ ALCL-cell lines and 75% and 83% of primary tumors, respectively. IL-9 was detected in serum-free culture medium harvested from ALK+ ALCL-cell lines, supporting autocrine release of IL-9. Treatment of these cells with an anti-IL-9-neutralizing antibody decreased pJak3 and its kinase activity, along with pStat3 and ALK kinase activity. These effects were associated with decreased cell proliferation and colony formation in soft agar and cell-cycle arrest. Evidence suggests that cell-cycle arrest can be attributed to up-regulation of p21 and down-regulation of Pim-1. Our results illustrate that IL-9/Jak3 signaling plays a significant role in the pathogenesis of ALK+ ALCL and that it represents a potential therapeutic target for treating patients with ALK+ ALCL.  相似文献   
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