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Avi Orr-Urtreger Anat Bar-Shira Dani Bercovich Noa Matarasso Uri Rozovsky Serena Rosner Sonya Soloviov Gad Rennert Luna Kadouri Ayala Hubert Hanna Rennert Haim Matzkin 《Cancer epidemiology, biomarkers & prevention》2006,15(3):474-479
Epidemiologic and genetic studies support the considerable effect of heritable factors on prostate tumorigenesis, although to date, no unequivocal susceptibility gene has been identified. The extensive study of RNASEL in prostate cancer patients worldwide has yielded conflicting results. We reevaluated the role of the RNASEL 471delAAAG Ashkenazi founder mutation in 1,642 Ashkenazi patients with prostate, bladder, breast/ovarian, and colon cancers; Ashkenazi controls; and in non-Ashkenazi prostate cancer patients and controls. The entire RNASEL coding sequence was also screened using denaturing high-performance liquid chromatography and multiplex ligation-dependent probe amplification for possible sequence variations or copy number changes in a population of prostate cancer patients. The 471delAAAG mutation was detected in 2.4% of the Ashkenazi prostate cancer patients; in 1.9% of patients with bladder, breast/ovarian, and colon cancers; and in 2.0% of the Ashkenazi controls. Seven additional variants were detected in RNASEL, including a novel potentially pathogenic splice site mutation, IVS5+1delG, although none were associated with increased prostate cancer risk. Multiplex ligation-dependent probe amplification analysis showed two RNASEL gene copies in all 300 prostate cancer patients tested. We estimated that the RNASEL 471delAAAG founder mutation, which was detected in 2% of the Ashkenazi Jews, originated between the 2nd and 5th centuries A.D., compared with the less frequent (1%) BRCA1 185delAG founder mutation, which originated hundreds of years earlier. Taken together, our analysis does not support a role for the RNASEL 471delAAAG Ashkenazi mutation nor for the other alterations detected in RNASEL in prostate cancer risk in Jewish men. 相似文献
34.
Rodriguez TV Gonzales JV Sanchez LM Perez MN Faz EM 《Journal of herbal pharmacotherapy》2005,5(4):31-38
The preliminary chemical characterization of the aqueous extract of Allophylus cominia (L.) Sw leaves was carried out by a phytochemical screening, the determination of the protein concentration by Lowry's method, as well as the composition of fatty acids and carbohydrates by gaseous chromatography (GC). The presence of the free amine groups, free phenolics, tannins, leucoantocianidines, saponines, triterpens, and steroids was detected. The concentration of proteins were 6.22 mg/mL. The composition of fatty acids (%) were: lauric acid (C12): 1.87; miristic acid (C14): 9.13; palmitic acid (C16): 19.87; stearic acid (C18): 8.35; and araquidic acid (C20): 7.83. The identified carbohydrates (mg/mg totals) were: arabinose: 0.06; xilose: 0.025; galactose: 0.241; and glucose: 1.2. Some members of these analyzed groups are reported in literature as potent hypoglycemic agents. For this reason, the presence of these substances in the analyzed extract may be one of the factors that contribute to the pharmacological effect of their administration in experimental diabetic models. 相似文献
35.
BACKGROUND: Policosanol is a cholesterol-lowering drug isolated from sugar cane wax with concomitant antiplatelet effects. Previous studies have shown that policosanol prevents lipofundin-induced atherosclerotic lesions in rabbits and rats, including foam cell formation, as well as the development of foam cells in carrageenan-induced granulomas in rats. Policosanol also inhibits smooth muscle cells proliferation induced on rabbit cuffed artery and on forceps-induced arterial wall damage. Furthermore, policosanol administered long term lowered serum cholesterol and prevented the development of atherosclerotic lesions in Macaca arctoides monkeys. The present study was undertaken to determine whether policosanol could change some characteristic features of atherosclerotic lesions, such as macrophage number and immunohistochemical localization of apoA-1 and apoB in aortas of M. arctoides monkeys. METHODS: Fourteen adult male monkeys weighing 6-10 kg and receiving a low fat, protein-rich diet were randomly distributed in three groups: control group (six monkeys) and two other groups (four monkeys/group) treated with policosanol (2.5 and 25 mg/kg) for 54 weeks. Samples of arteries were examined by light microscopy. Monoclonal antibodies were used to evaluate the presence of macrophage, apoA-1 and apoB. RESULTS: Policosanol reduced the presence of macrophages and the occurrence of apoB, whereas increased apoA-1 localization in aortic atherosclerotic lesions compared with control monkeys. CONCLUSIONS: These results suggest the policosanol potential benefit on plaque composition and stability and could explain the protective effects of policosanol on atherosclerosis development. 相似文献
36.
Avigad S Peleg D Barel D Benyaminy H Ben-Baruch N Taub E Shohat M Goshen Y Cohen IJ Yaniv I Zaizov R 《Journal of pediatric hematology/oncology》2004,26(9):541-545
PURPOSE: The hallmark of Li-Fraumeni syndrome (LFS), a familial cancer syndrome, is constitutional TP53 mutation. The authors addressed the complex question of predictive prenatal genetic testing for cancer risk associated with inheritance of TP53 mutation. METHODS: A classic LFS family including the proband (a 20-month-old boy with rhabdomyosarcoma), his 36-year-old father with osteosarcoma, and his 40-year-old paternal aunt with bilateral breast cancer were identified as carriers of a TP53 germline mutation, a novel 1 base pair deletion in exon 5. A few years later, the mother became pregnant twice, and the parents requested prenatal diagnosis on each occasion. Genetic counseling, psychological evaluation, and support were provided by a multidisciplinary team including a pediatric oncologist, a geneticist, a psychosocial worker, a prenatal care provider, and an ethical representative. After providing overall information on LFS, including the high risk of developing secondary multiple neoplasms in LFS survivors, the committee approved prenatal diagnosis at the request of the family. RESULTS: In the two pregnancies, the two fetuses were found to be carriers of the same mutation. Nine years from diagnosis of the first tumor, the proband, and a month later his father, developed second tumors, multifocal osteosarcoma and leiomyosarcoma, respectively. CONCLUSIONS: Children with primary tumors belonging to LFS should be considered for screening for germline mutations and genetic counseling by a multidisciplinary team. Whether family members are found to be positive or negative as carriers, such measures may provide, by reducing uncertainty, psychological benefit to high-risk families. 相似文献
37.
Gámez R Más R Noa M Menéndez R García H González J Perez Y Goicochea E 《Drugs under experimental and clinical research》2004,30(2):75-88
D-003 is a mixture of high molecular weight aliphatic primary acids purified from sugar cane wax (Saccharum officinarum, L) with cholesterol-lowering and antiplatelet effects. Previous studies, including a 6-month study conducted in rats, have shown no D-003-related toxicity. The present study was undertaken to investigate the effects of D-003 orally administered for 9 months in beagle dogs. The animals were randomly distributed in three groups: a control group receiving the vehicle only and two groups orally administered D-003 (200 and 400 mg/kg). Body weight gain, food consumption and clinical signs were controlled throughout the study. The effects of D-003 on collagen-induced platelet aggregation, bleeding time (BT) and coagulation parameters (prothrombin time and kaolin-activated thromboplastin time) were also investigated. Most blood biochemistry and hematological parameters were assessed at baseline and after 6 and 9 months of treatment, while total cholesterol (TC), triglycerides, platelet aggregation, BT and coagulation parameters were determined at baseline and after 9 months of treatment. At study completion, the animals were sacrificed. D-003 at a dose of 200 and 400 mg/kg significantly reduced TC (p < 0.05), significantly inhibited platelet aggregation and increased BT compared with levels in controls. Data analyses of body weight gain, food consumption, clinical observations, the remaining blood biochemistry and hematology indicators (including coagulation parameters, organ weight ratios and histopathological findings) showed no trends with D-003 doses or significant differences between control animals and treated groups. In conclusion, D-003 administered for 9 months to beagle dogs induced the expected effects with no evidence of drug-related toxicity. 相似文献
38.
Preservation of tubal function following methotrexate treatment for ectopic pregnancy 总被引:5,自引:0,他引:5
Suzuki T Izumi S Awaji H Matsubayashi H Yoshikata K Kika G Murano T Shida M Uchida N Cai L Kondo M Yoshitake T Makino T 《The Tokai journal of experimental and clinical medicine》2004,29(4):183-189
To evaluate methotrexate (MTX) administration as a conservative treatment for ectopic pregnancy, we reviewed the medical records of 248 cases (210 patients) of MTX treatment for tubal pregnancies at our department between December 1985 and December 2003, and compared its pregnancy prognosis with that of laparoscopic salpigotomy (59 patients). With the MTX treatment, 185 patients were successfully treated, and the subsequent pregnancy rate and ectopic pregnancy rate were 48.4 % and 18.4 %, respectively, while those rates were 49.2 % and 18.6 %, respectively, after the salpigotomy. These results suggest that MTX treatment is comparable to the more conservative operation. To clarify the (dys/) function of the ectopic implantation tubes and MTX-treated tube (s), we excluded patients who had a contra-lateral healthy tube, and extracted 40 patients as "the affected tube group", where the pregnancy-related parameters were not adversely affected. The findings suggest that MTX is not necessary to preserve tubal function. 相似文献
39.
Carbajal D Noa M Molina V Arruzazabala ML Más R Mendoza S González J 《Journal of medicinal food》2003,6(1):13-18
D-003 is a mixture of high-molecular-weight aliphatic primary acids purified from sugar cane wax with antiplatelet and cholesterol-lowering effects. Cardiac lesions induced by isoproterenol (ISO) are characterized by myocardial necrosis and exudative infiltration. The objective of this study was to determine whether D-003 shows protective effects against ISO-induced myocardial necrosis in rats. Effects of orally administered single doses of D-003 (25-400 mg/kg) and acetylsalicylic acid (ASA, 30 mg/kg), as well as repeated doses of D-003 (5-200 mg/kg), on characteristic markers of ISO-induced myocardial necrosis in rats were investigated. D-003 administered as single doses dose-dependently decreased necrosis area, percent of infarct area, and the presence of polymorphonuclear cells (PMNs) in myocardial tissue, but only the reductions induced by 200 and 400 mg/kg were significant. Oral acute treatment with ASA also decreased necrosis area and percent of infarct area, but the occurrence of PMNs was unchanged. D-003 administered repeatedly for 10 days also decreased all myocardial necrosis indicators in a dose-dependent manner, with results effective from 25 mg/kg to the highest dose tested, indicating that the repeated dose scheme was more effective to prevent the damage. It is concluded that D-003 shows a protective effect on the myocardial necrosis induced by ISO in rats. 相似文献
40.
R. Gmez M. Noa R. Mas N. Mendoza B. Pardo R. Menndez Y. Prez R.M. Gonzlez A. Gutirrez G. Marrero E. Goicochea H. García D. Curveco 《Food and chemical toxicology》2007,45(12):2352-2358
D-003 is a mixture of high molecular weight sugarcane wax aliphatic primary acids with cholesterol-lowering, anti-platelet and antioxidant effects. This study investigated the long-term oral toxicity and carcinogenicity of D-003 in Sprague Dawley rats of both sexes, randomly distributed into four groups: a control group, treated only with the vehicle, and three treated with D-003 (50, 500 and 1500 mg/kg). All treatments were given orally for 24 months. Mortality (survival analysis), clinical symptoms, weight gain, food consumption, organ weights, time-to-tumour or tumour incidence data were not shown between group differences or trends. With the exception of serum cholesterol levels, lower in D-003-treated groups (500 and 1500 mg/kg) than in the controls, no other difference in blood indicators was found. D-003 did not increase the frequency of neoplastic and non-neoplastic lesions compared with the controls. The occurrence of all malignant and mammary tumours in D-003-treated females was lower than in the controls. The lesions observed were consistent with spontaneous lesions reported in this species. In conclusion, D-003 is not toxic or carcinogenic when given orally to Sprague Dawley rats up to 1500 mg/kg for 2 years, and 1500 mg/kg was a not-observable effect dose. 相似文献