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151.
Induction of apoptosis in human lung cancer cells by curcumin 总被引:25,自引:0,他引:25
Radhakrishna Pillai G Srivastava AS Hassanein TI Chauhan DP Carrier E 《Cancer letters》2004,208(2):163-170
Curcumin, a phenolic compound from the rhizome of the plant Curcuma longa has anti-inflammatory, antioxidant and anti-cancer activities. Although the precise mode of action of this compound is not yet elucidated, studies have shown that chemo-preventive action of curcumin might be due to its ability to induce apoptosis and to arrest cell cycle. This study investigated the cellular and molecular changes induced by curcumin leading to the induction of apoptosis in human lung cancer cell lines-A549 and H1299. A549 is p53 proficient and H1299 is p53 null mutant. The lung cancer cells were treated with curcumin (0-160 microM) for 12-72 h. Curcumin inhibited the growth of both the cell lines in a concentration dependent manner. Growth inhibition of H1299 cell lines was both time and concentration dependent. Curcumin induced apoptosis in both the lung cancer cell lines. A decrease in expression of p53, bcl-2, and bcl-X(L) was observed after 12 h exposure of 40 microM curcumin. Bak and Caspase genes remained unchanged up to 60 microM curcumin but showed decrease in expression levels at 80-160 microM. The data also suggest a p53 independent induction of apoptosis in lung cancer cells. 相似文献
152.
Abdelkefi A Ben Othman T Kammoun L Chelli M Romdhane NB Kriaa A Ladeb S Torjman L Lakhal A Achour W Ben Hassen A Hsaïri M Ladeb F Ben Abdeladhim A 《Thrombosis and haemostasis》2004,92(3):654-661
We have conducted a prospective randomized controlled trial to evaluate the role of low-dose unfractionated heparin prophylaxis in preventing central venous line-related thrombosis in patients with haemato-oncological disease. Patients were randomly assigned to receive either prophylactic intravenous unfractionated heparin (continuous infusion of 100 IU/kg/daily) or 50 ml/daily of normal saline solution as a continuous infusion. CVLs were externalized, non tunneled, double lumen catheters. All CVLs were placed percutaneously by the same physician in the subclavian vein. Upper limb veins were systematically examined by ultrasonography just before, or <24 hours after, catheter removal, and in case of clinical signs of thrombosis. One hundred and twenty-eight CVLs were inserted. Catheter-related thrombosis occurred in 1.5% of the catheters inserted in patients of the heparin group, and in 12.6% in the control group (p = 0.03). No other risk factors were found for the development of catheter-related thrombosis. Two and three patients experienced severe bleeding in the heparin group, and in the control group, respectively (p = 0.18). There were no other side-effects clearly ascribable to the use of unfractionated heparin. This is the first prospective, randomized study, which shows that low-dose of unfractionated heparin is safe and effective to prevent catheter-related thrombosis in patients with haemato-oncological disease. 相似文献
153.
Sabry SM Barary MH Abdel-Hay MH Belal TS 《Journal of pharmaceutical and biomedical analysis》2004,34(3):509-516
The stripping voltammetric behaviour of buspirone hydrochloride (BUS) and piribedil (PIR), as models of pyrimidine-containing compounds, was studied using a hanging mercury drop electrode (HMDE). A sensitive adsorptive stripping voltammetric method for determination of such drugs is described. The voltammetric peaks were obtained at -1.23 and -1.22 V for BUS and PIR. respectively, which correspond to the reduction of the azomethine group of pyrimidine ring in Britton-Robinson buffer (pH 7). Factors such as pH of supporting electrolyte, accumulation potential and time and instrumental parameters were optimized. Calibration plots and regression data validation, accuracy, precision, limits of detection, limits of quantification, and other aspects of analytical merit are presented. The applicability of the method was evaluated through determination of BUS and PIR in tablet dosage forms. A preliminary study of the analysis of plasma samples, spiked with the investigated drug, after a simple extraction procedure is described. 相似文献
154.
155.
Amira Gamal Abdel-Rahman Mohamed Farouk Allam Maha M. El Gaafary Mohamed Tarek Mansour Mustafa Abdel-Aziz Mustafa 《Clinical & translational oncology》2004,6(3):159-164
Introduction
Polycyclic aromatic hydrocarbons (PAH) are environmental contaminants that have been of interest in cancer research for a considerable length of time. DNA adduct formation is considered a marker and indicator for exposure to PAH. The aim of this study was to determine PAH-DNA adduct levels in peripheral blood lymphocytes and urine obtained from workers exposed to PAH, and to evaluate tobacco use, GSTM1 and GSTT1 as possible contributory risk factors.Material and methods
Our study included a random sample of 66 workers exposed to PAH and 49 non-exposed workers.Results
PAH-DNA adduct levels of exposed workers were lower than that of the non-exposed group (p<0.05). However, current smoking, GSTM1-negatives, and current smoking with GSTM1-negatives were more frequent in the non-exposed group. In addition, non-exposed workers reported exposure to PAH in their current jobs, as compared with the exposed group (p<0.001). Linear regression analysis identified the levels of benzo-[b]-fluoranthene in the working area as the only significant DNA adduct-forming risk factor (p=0.025).Conclusion
Further research, with an appropriately large sample size, is highly recommended in measuring PAH-DNA adduct levels and evaluating their relationship with the different types of PAH. 相似文献156.
Pregnancy outcome in spontaneous twins versus twins who were conceived through in vitro fertilization 总被引:4,自引:0,他引:4
Nassar AH Usta IM Rechdan JB Harb TS Adra AM Abu-Musa AA 《American journal of obstetrics and gynecology》2003,189(2):513-518
OBJECTIVE: The purpose of this study was to compare maternal and neonatal complications in spontaneous versus in vitro fertilization twins. STUDY DESIGN: Twin gestations that were delivered from 1995 to 2000 were reviewed. Cases consisted of 56 in vitro fertilization twins, each of which was matched to two control mothers by age and parity. They were compared regarding various maternal and neonatal complications. RESULTS: In vitro fertilization twins were more likely to have preterm labor compared with control twins, with no difference in the incidences of pregnancy-induced hypertension, gestational diabetes mellitus, placenta previa, or preterm premature rupture of membranes between the two groups. The cesarean delivery rate was significantly higher in cases of twins who were conceived by in vitro fertilization (76.8% vs 58.0%, P=.026), despite a similar rate of elective cesarean delivery and the incidence of nonvertex twin A in both groups. The preterm delivery rate was significantly higher (67.9% vs 41.1%, P=.002) and the gestational age was significantly lower (35+/-3 weeks vs 36+/-3 weeks, P=.043) in cases compared with control subjects. Both twins were, on the average, 230 g lighter in the in vitro fertilization group compared with the control group. However, intrauterine growth restriction was more frequent in the control group (36.6% vs 25%, P=.044). There was a significantly higher incidence of admission to the neonatal intensive care unit, respiratory distress syndrome, a need for mechanical ventilation, and pneumothorax in cases compared with control subjects. CONCLUSION: When compared with spontaneous twins, in vitro fertilization twins are more likely to be delivered by cesarean delivery and to have a higher incidence of preterm birth and prematurity-related respiratory complications with a longer nursery stay. 相似文献
157.
We describe a case of adenomatous polyp of the colon that harbored small foci of signet ring cell carcinoma. The patient was a 64-year-old woman with end-stage renal disease and sepsis who underwent colonoscopy to evaluate the possibility of pseudomembranous colitis. A polyp was found incidentally in the right colon and a biopsy was performed. Histologic examination of the polyp revealed typical features of tubular adenoma without evidence of high-grade dysplasia. However, 2 small foci of signet ring cell carcinoma were identified that infiltrated the lamina propria. In contrast to adenomatous epithelium, the signet ring cells were immunohistochemically positive for cytokeratin 7 and negative for cytokeratin 20, suggesting a metastasis rather than a primary tumor. Multiple random biopsies from the right and left colon, as well as the ileum, exhibited no histologic evidence of malignancy. Subsequently, signet ring cell carcinoma with similar morphology and identical immunophenotype was detected in biopsies from the endometrium, an unusual location for primary signet ring cell carcinoma. Preliminary workup excluded the breast as a possible primary site, but further investigation was not possible because of the patient's death with no autopsy granted. To the best of our knowledge, this is the first reported case of metastatic signet ring cell carcinoma to an adenomatous polyp of the colon. This case illustrates the necessity of submitting all polyps entirely and the importance of examining them carefully. 相似文献
158.
Laparoscopic staging compared with imaging techniques in the staging of advanced cervical cancer 总被引:1,自引:0,他引:1
Hertel H Köhler C Elhawary T Michels W Possover M Schneider A 《Gynecologic oncology》2002,87(1):46-51
OBJECTIVE: We evaluated the evidence of laparoscopy for decision regarding treatment options in advanced cervical cancer patients. METHODS: One hundred nine consecutive patients with cervical cancer FIGO stage Ib2 and higher underwent laparoscopic staging of the extent of disease. Laparoscopic and histopathologic evaluation of tumor involvement of the paraaortic and pelvic lymph nodes, wall of the bladder, and rectal pillar was compared with preoperative findings of MRI and/or CT. RESULTS: Paraaortic lymphadenectomy was performed in 101 (92.7%) patients and 21 (19.3%) patients had positive paraaortic lymph nodes. Pelvic lymphadenectomy was performed in 75 (68.8%) patients and 20 (26.7%) patients had positive pelvic lymph nodes. In 11 patients (11.5%) infiltration of the bladder and in 6 patients (6.25%) infiltration of the rectal pillar or cul-de-sac was found. Intraoperative complications associated with laparoscopic staging occurred in 3.7% of patients. The negative predictive value for the evaluation of paraaortic or pelvic lymph nodes, the bladder wall, rectal pillar, and cul-de-sac ranged from 73% (CT for pelvic lymph nodes) to 96% (MRI for bladder wall). Lack of information about the extent of disease was adjusted on the basis of laparoscopic findings in 24 (22%) patients and improved treatment plans. CONCLUSION: Laparoscopic staging of patients with advanced cervical cancer is accurate, associated with low morbidity, and helps to adjust treatment according to extent of disease. 相似文献
159.
160.
Tobacco use by university students,Lebanon, 2001 总被引:2,自引:0,他引:2
Tamim H Terro A Kassem H Ghazi A Khamis TA Hay MM Musharrafieh U 《Addiction (Abingdon, England)》2003,98(7):933-939
Aims The objective was to determine the prevalence of smoking [cigarettes and/or narghile (i.e. water‐pipe)] among university students and to examine multiple correlates. Design Cross‐sectional. Setting Beirut, Lebanon. Participants A proportionate random sample of 1964 students from public and private universities in Beirut, Lebanon. Measurements Participants completed a self‐administered anonymous questionnaire that included demographic and scholastic items and health behavioral aspects, including smoking, alcohol, physical activity, weight control measures and seat belt use. Findings The overall prevalence of smoking was 40% (21.1%, 7.6% and 11.3% of the students were smoking only narghile, only cigarettes and both cigarettes and narghile, respectively). Regression analyses showed that males, those of non‐Lebanese origin, pursuing undergraduate degrees, performing risky weight control measures and drinking excessive amounts of alcohol had increased odds of smoking cigarettes. Also, age, high level of paternal education and field of study were significant predictors. Narghile smoking was significantly higher among males who drank excessive alcohol. Conclusions The authors advocate a collaborative effort to alleviate the consequences of smoking among university students. 相似文献