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91.

Ethnopharmacological relevance

Terminalia chebula has an esteemed origin in Indian mythology; its fruits are used to treat many diseases such as digestive, diabetes, colic pain, chronic cough, sore throat, asthma, etc.

Aim of the study

The water or ethanolic extracts of the fruits were reported to have anti-oxidant, anti-inflammatory, anti-cancer and radio-protector properties. The present study is to isolate and identify the compounds that inhibit COX and 5-LOX, the key enzymes involved in inflammation and carcinogenesis.

Materials and methods

The ethanolic extract of the fruits was fractionated by RP-HPLC and fractions were tested for enzyme inhibition activity against COX and 5-LOX. One of the fractionated compounds showed potent dual inhibition against COX and 5-LOX. It was identified as chebulagic acid by LC–MS, NMR and IR analyses. The chebulagic acid was also tested for anti-proliferative activity.

Results

Chebulagic acid showed potent COX–LOX dual inhibition activity with IC50 values of 15 ± 0.288, 0.92 ± 0.011 and 2.1 ± 0.057 μM for COX-1, COX-2 and 5-LOX respectively. It also showed anti-proliferative activity against HCT-15, COLO-205, MDA-MB-231, DU-145 and K562 cell lines. Further mechanistic studies on COLO-205 cells revealed induction of apoptosis by chebulagic acid.

Conclusions

Chebulagic acid, a COX-2 and 5-LOX dual inhibitor isolated from the fruits of Terminalia chebula, induces apoptosis in COLO-205 cells.  相似文献   
92.
93.
AIM: To evaluate the accuracy of endoscopic ultrasound (EUS) for staging of gastric cancers.
METHODS: Only EUS studies confirmed by surgery were selected. Only studies from which a 2×2 table could be constructed for true positive, false negative, false positive and true negative values were included. Articles were searched in Medline, Pubmed, Ovid journals, Cumulative index for nursing & allied health literature, International pharmaceutical abstracts, old Medline, Medline nonindexed citations, and Cochrane control trial registry. Two reviewers independently searched and extracted data. The differences were resolved by mutual agreement. 2×2 tables were constructed with the data extracted from each study. Meta-analysis for the accuracy of EUS was analyzed by calculating pooled estimates of sensitivity, specificity, likelihood ratios, and diagnostic odds ratio. Pooling was conducted by both the Mantel-Haenszel method (fixed effects model) and DerSimonian Laird method (random effects model). The heterogeneity of studies was tested using Cochran's Q test based upon inverse variance weights.
RESULTS: Initial search identified 1620 reference articles and of these, 376 relevant articles were selected and reviewed. Twenty-two studies (n = 1896) which met the inclusion criteria were included in this analysis. Pooled sensitivity of T1 was 88.1% (95% CI: 84.5-91.1) and T2 was 82.3% (95% CI: 78.2-86.0). For T3, pooled sensitivity was 89.7% (95% CI: 87.1-92.0). T4 had a pooled sensitivity of 99.2% (95% CI: 97.1-99.9). For nodal staging, the pooled sensitivity for N1 was 58.2% (95% CI: 53.5-62.8) and N2 was 64.9% (95% CI: 60.8-68.8). Pooled sensitivity to diagnose distant metastasis was 73.2% (95% CI: 63.2-81.7). The P for chi-squared heterogeneity for all the pooled accuracy estimates was 〉0. 10.
CONCLUSION: EUS results are more accurate with advanced disease than early disease. If EUS diagnoses advanced disease, such as T4 disease, the patient is  相似文献   
94.
Purpose: This study aimed to determine the real-world prognostic significance of lymph node ratio (LNR) and log odds of positive lymph nodes (LOPLN) in patients with non-metastatic small bowel adenocarcinoma. Methods: Patients diagnosed with early-stage small bowel adenocarcinoma between January 2007 and December 2018 from a large Canadian province were identified. We calculated the LNR by dividing positive over total lymph nodes examined and the LOPLN as log ([positive lymph nodes + 0.5]/[negative lymph nodes + 0.5]). The LNR and LOPLN were categorized at cut-offs of 0.4 and −1.1, respectively. Multivariable Cox proportional hazards models were constructed for each nodal stage, LNR and LOPLN, adjusting for measured confounding factors. Harrell’s C-index and Akaike’s Information Criterion (AIC) were used to calculate the prognostic discriminatory abilities of the different models. Results: We identified 141 patients. The median age was 67 years and 54.6% were men. The 5-year overall survival rates for patients with stage I, II and III small bowel adenocarcinoma were 50.0%, 56.6% and 47.5%, respectively. The discriminatory ability was generally comparable for LOPLN, LNR and nodal stage in the prognostication of all patients. However, LOPLN had higher discriminatory ability among patients with at least one lymph node involvement (Harrell’s C-index, 0.75, 0.77 and 0.82, and AIC, 122.91, 119.68 and 110.69 for nodal stage, LNR and LOPLN, respectively). Conclusion: The LOPLN may provide better prognostic information when compared to LNR and nodal stage in specific patients.  相似文献   
95.
ABSTRACT: The purpose of the current study was to determine whether a tropical ginger derived compound 1'-acetoxychavicol acetate (ACA), suppresses skin tumor promotion in K5.Stat3C mice. In a two-week study in which wild-type (WT) and K5.Stat3C mice were co-treated with either vehicle, ACA, galanga extract, or fluocinolone acetonide (FA) and tetradecanoyl phorbol acetate (TPA), only the galanga extract and FA suppressed TPA-induced skin hyperproliferation and wet weight. None of these agents were effective at suppressing pTyr705 Stat3 expression. However, ACA and FA showed promising inhibitory effects against skin tumorigenesis in K5.Stat3C mice. ACA also suppressed phospho-p65 NF-kappaB activation, suggesting a potential mechanism for its action.  相似文献   
96.
97.
Serum prolactin was measured pretherapeutically and sequentially thereafter using immunoradiometric assay method in 37 male patients with advanced tongue cancer and compared with 23 healthy, age-matched controls. Prolactin levels were correlated with age, various clinicopathologic parameters, overall survival, and patients with response and those with progressive disease. Patients with advanced tongue cancer had higher prolactin levels than controls (P < 0.02), but intergroup variation in prolactin was not observed when considering the age, site of the lesion, disease stage, histologic grade, and keratin. Of the patients, 30% had hyperprolactinemia (prolactin >15.0 ng/ml). To assess the prognostic significance of pretherapeutic prolactin level, the patients were divided according to the cutoff level of prolactin (15.0 ng/ml). Hyperprolactinemic patients had more unfavourable prognosis than patients with prolactin <15.0 ng/ml (X2=2.91, df=1, P < 0.0037). In monitoring disease course, patients who responded to treatments had decreased prolactin levels at the end of 18 months as compared to their pretherapeutic levels (P < 0.01). In patients who subsequently developed progressive disease within 18 months, prolactin levels reduced initially at response, whereas with disease progression, prolactin levels increased significantly (P < 0.05). The positive and negative predictive value of prolactin was 100%. Immunohistochemical localization confirmed the ectopic production of prolactin by tongue tumors. In conclusion, our data indicate that hyperprolactinemia may be an independent predictor of short-term prognosis; circulating prolactin may be used as a marker for monitoring disease course in patients with advanced tongue cancer, and prolactin is produced ectopically by tongue tumors. © 1994 Wiley-Liss, inc.  相似文献   
98.
One hundred sixty seven children were operated at the Kalawati Saran Children Hospital for acute peritonitis during last 10 years (1978–88). Bowel perforation was seen in 123 cases. Nineteen cases had underlying Tubercular enteritis. Preoperative diagnosis was usually difficult. The terminal ileum was affected in 12 and the jejunum in 5 cases. Multiple perforations were seen in 3 cases. Postoperative mortality was high (12/19) and usually attributable to their poor preoperative status.  相似文献   
99.
AIMS: The primary aims of these two single-centre, randomized, evaluator-blind, placebo/positive-controlled, parallel-group studies were to evaluate the potential for pharmacodynamic and pharmacokinetic interaction between ezetimibe 0.25, 1, or 10 mg and simvastatin 10 mg (Study 1), and a pharmacodynamic interaction between ezetimibe 10 mg and simvastatin 20 mg (Study 2). Evaluation of the tolerance of the coadministration of ezetimibe and simvastatin was a secondary objective. METHODS: Eighty-two healthy men with low-density lipoprotein cholesterol (LDL-C) >or=130 mg dl-1 received study drug once daily in the morning for 14 days. In Study 1 (n=58), five groups of 11-12 subjects received simvastatin 10 mg alone, or with ezetimibe 0.25, 1, or 10 mg or placebo. In Study 2 (n=24), three groups of eight subjects received simvastatin 20 mg alone, ezetimibe 10 mg alone, or the combination. Blood samples were collected to measure serum lipids in both studies. Steady-state pharmacokinetics of simvastatin and its beta-hydroxy metabolite were evaluated in Study 1 only. RESULTS: In both studies, reported side-effects were generally mild, nonspecific, and similar among treatment groups. In Study 1, there were no indications of pharmacokinetic interactions between simvastatin and ezetimibe. All active treatments caused statistically significant (P<0.01) decreases in LDL-C concentration vs placebo from baseline to day 14. The coadministration of ezetimibe and simvastatin caused a dose-dependent reduction in LDL-C and total cholesterol, with no apparent effect on high-density lipoprotein cholesterol (HDL-C) or triglycerides. The coadministration of ezetimibe 10 mg and simvastatin 10 mg or 20 mg caused a statistically (P<0.01) greater percentage reduction (mean -17%, 95% CI -27.7, -6.2, and -18%, -28.4, -7.4, respectively) in LDL-C than simvastatin alone. CONCLUSIONS: The coadministration of ezetimibe at doses up to 10 mg with simvastatin 10 or 20 mg daily was well tolerated and caused a significant additive reduction in LDL-C compared with simvastatin alone. Additional clinical studies to assess the efficacy and safety of coadministration of ezetimibe and simvastatin are warranted.  相似文献   
100.
Potent enzyme inhibitors have long been recognized as powerful tools for assessing the physiological roles of enzymes and have led to the therapeutic drugs able to modulate their activities in vivo. However, to be valuable tools such inhibitors should be selective so that they do not interfere with other members of the particular enzyme family. Combinatorial chemistry has proven to be a novel approach for the identification of molecules with a desired selectivity profile from the libraries of several million compounds. In recent years it has been extensively used in conjunction with computational methods for the development of potent inhibitors of therapeutically interesting targets. This review describes the various structurally diverse enzyme inhibitors identified by screening combinatorial libraries of peptides and small organic molecules.  相似文献   
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