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101.
102.
Weniger B Um BH Valentin A Estrada A Lobstein A Anton R Maillé M Sauvain M 《Journal of natural products》2001,64(9):1221-1223
A new prenylated acridone alkaloid, 1,3,5-trihydroxy-2,8-bis(3-methylbut-2-enyl)-10-methyl-9-acridone (1), was isolated from the stembark of Swinglea glutinosa, along with three known acridone alkaloids, 5-hydroxynoracronycine (2), 1,3,5-trihydroxy-4-methoxy-2-(3-methylbut-2-enyl)-10-methyl-9-acridone (3), and 1,3,5-trihydroxy-4-methoxy-10-methylacridone (4). The isolated alkaloids were assessed in vitro against chloroquine-sensitive and -resistant Plasmodium falciparum strains and for cytotoxicity using HeLa cells. 相似文献
103.
Asian-American variants of human papillomavirus 16 and risk for cervical cancer: a case-control study 总被引:9,自引:0,他引:9
Berumen J Ordoñez RM Lazcano E Salmeron J Galvan SC Estrada RA Yunes E Garcia-Carranca A Gonzalez-Lira G Madrigal-de la Campa A 《Journal of the National Cancer Institute》2001,93(17):1325-1330
BACKGROUND: Human papillomavirus 16 (HPV16) has a number of variants, each with a different geographic distribution and some that are associated more often with invasive neoplasias. We investigated whether the high incidence of cervical cancer in Mexico (50 cases per 100 000 women) may be associated with a high prevalence of oncogenic HPV16 variants. METHODS: Cervical samples were collected from 181 case patients with cervical cancer and from 181 age-matched control subjects, all from Mexico City. HPV16 was detected with an E6/E7 gene-specific polymerase chain reaction, and variant HPV classes and subclasses were identified by sequencing regions of the E6 and L1/MY genes. Clinical data and data on tumor characteristics were also collected. All statistical tests were two-sided. RESULTS: HPV16 was detected in cervical scrapes from 50.8% (92 of 181) of case patients and from 11% (20 of 181) of control subjects. All HPV16-positive samples, except one, contained European (E) or Asian-American (AA) variants. AA and E variants were found statistically significantly more often in case patients (AA = 23.2% [42 of 181]; E = 27.1% [49 of 181]) than in control subjects (AA = 1.1% [two of 181]; E = 10% [18 of 181]) (P<.001 for case versus control subjects for either E or AA variants, chi2 test). However, the frequency of AA variants was 21 times higher in cancer patients than in control subjects, whereas that ratio for E variants was only 2.7 (P =.006, chi2 test). The odds ratio (OR) for cervical cancer associated with AA variants (OR = 27.0; 95% confidence interval [CI] = 6.4 to 113.7) was higher than that associated with E variants (OR = 3.4; 95% CI = 1.9 to 6.0). AA-positive case patients (46.2 +/- 12.5 years [mean +/- standard deviation]) were 7.7 years younger than E-positive case patients (53.9 +/- 12.2 years) (P =.004, Student's t test). AA variants were associated with squamous cell carcinomas and adenocarcinomas, but E variants were associated with only squamous cell carcinomas (P =.014, Fisher's exact test). CONCLUSIONS: The high frequency of HPV16 AA variants, which appear to be more oncogenic than E variants, might contribute to the high incidence of cervical cancer in Mexico. 相似文献
104.
Role of genitourinary inflammation in infertility: synergistic effect of lipopolysaccharide and interferon-gamma on human spermatozoa 总被引:1,自引:0,他引:1
Sikka SC Champion HC Bivalacqua TJ Estrada LS Wang R Rajasekaran M Aggarwal BB Hellstrom WJ 《International journal of andrology》2001,24(3):136-141
Pro-inflammatory cytokines are elevated in the semen of patients with genitourinary inflammation (GUI). Whether this increase in cytokines in GUI patients plays any critical role in male factor infertility is not clear. The present study investigated the in vitro effects of two important pro-inflammatory cytokines, lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma), on sperm motility, viability, membrane integrity and motion parameters. Washed spermatozoa from healthy donors were incubated with LPS (0.1 mg/mL) or IFN-gamma (0.1 mg/mL) alone or in combination. Sperm motility, viability, membrane integrity and computer-assisted motion were evaluated at various time intervals (0, 30, 60 and 180 min) after treatment. Sperm membrane integrity was analysed using the hypo-osmotic swelling test (HOST). LPS and IFN-gamma individually did not alter sperm viability or motility, but their combination showed a significant time-dependent decrease (p < 0.05) in sperm motility, viability and membrane integrity. Sperm motion parameters (straight-line velocity, curvilinear velocity, mean linearity, or amplitude of lateral head displacement) were not affected by LPS or IFN-gamma at the concentrations used in this study. These data suggest that the combination of LPS and IFN-gamma is detrimental to human spermatozoa and may contribute to male factor infertility in patients with chronic GUI. 相似文献
105.
Homocysteine (Hcy) levels have been shown to be a predeterminant of thrombotic diseases. We measured the Hcy levels of 50 blacks and 50 whites equally divided by gender to determine if there is a significant racial difference in either fasting or random Hcy levels. Dietary, medication, smoking, alcohol, past medical, educational, and occupational histories were obtained, and the body mass index calculated. Total serum fasting and random Hcy levels, B12, folate, BUN, creatinine, and lipid profiles were drawn from each participant. Analysis of the results showed that white males have the highest fasting Hcy levels, 10.5 microM/l, whereas random Hcy levels were not significantly different. Correlation between fasting and random Hcy levels was poor (R = 0.61). B12 levels in black subjects were significantly higher, 490.8 pg/ml, compared to whites, 382.8 pg/ml, P = 0.001, but contributed little to total Hcy levels (R(2) = 0.08). Folic acid levels, all within normal range, were not significantly different between the two racial groups and also did not appear to greatly affect Hcy levels (R(2) = 0.06). Our study demonstrates that, despite the genetic diversity of these two racial groups in the U.S., white males in this age group have higher fasting Hcy levels than black males, and white males, but not black males, have higher fasting homocysteine levels than females. This discrepancy in Hcy levels may reflect methylene-tetrahydrofolate reductase (MTHFR) enzyme polymorphisms, known to be higher in whites, rather than socioeconomic influences. 相似文献
106.
Prednisolone plus albuterol versus albuterol alone in mild to moderate bronchiolitis 总被引:4,自引:0,他引:4
To evaluate combination therapy of mild to moderate bronchiolitis with bronchiodilators and corticosteroids, we treated 51 young children with first-time wheezing and symptoms of respiratory tract infection with albuterol plus either prednisolone or placebo for 5 days. Disease severity was scored on days 0, 2, 3, and 6. On day 2, prednisolone resulted in significantly lower scores (2.7 +/- 1.4 vs. 4.0 +/- 1.5 in all patients evaluated, p < 0.05) than placebo, whereas there was no detectable difference on day 6, suggesting that addition of prednisolone to albuterol transiently accelerates recovery from bronchiolitis. The clinical significance of this effect needs to be evaluated in further studies. 相似文献
107.
Health Literacy and Numeracy 总被引:2,自引:0,他引:2
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110.
Dominique Scherer Eduardo Nagore Justo Lorenzo Bermejo Adina Figl Rafael Botella‐Estrada Ranjit Kumar Thirumaran Sabrina Angelini Kari Hemminki Dirk Schadendorf Rajiv Kumar 《International journal of cancer. Journal international du cancer》2009,125(8):1868-1875
Variation within the melanocortin receptor 1 (MC1R) gene, that influences phenotypic traits and susceptibility to melanoma, is abundant across the populations. We assessed and compared the risk of melanoma in 2 European populations, German and Spanish, by genotyping MC1R variants through direct DNA sequencing from 1,185 melanoma cases and 1,582 controls. The presence of any variant in both populations was associated with a significantly increased risk of melanoma (odds ratio OR = 1.67, 95% confidence interval CI 1.40–1.99). The population attributable fractions (PAF) associated with the MC1R variants in both populations was over 25%. However, the results showed a statistically significant (p < 0.0001) higher frequency of MC1R variants in the German (70%) than in the Spanish population (60%). The red‐hair colour (RHC) variants, though associated with increased risk in both populations, were more common in the German than in the Spanish population (p < 0.0001). Interestingly, non‐RHC variants increased the disease risk in the Spanish (OR = 1.60, 95% CI 1.20–2.14) but not in the German population (OR = 1.07, 95% CI 0.80–1.44). Although RHC variants explained a major proportion of the observed PAF in the German population, in the Spanish population the major contributor to the PAF was the non‐RHC V60L variant. We also observed reduced historic linkage disequilibrium between the variants V92M and T314T in the gene in German melanoma cases. In conclusion, our data underscored the unambiguous importance of the MC1R variants towards the population burden of melanoma. However, the variants that are associated with the disease differ between the investigated populations. © 2009 UICC 相似文献