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91.
Objective: Data have suggested that higher levels of nutrients are protective against HPV persistence and cervical neoplasia. This study assessed the role of circulating nutrients on clearance of oncogenic HPV infections. Methods: Women were followed prospectively with visits at baseline and approximately 4- and 10-months post-baseline. At each visit, 15 oncogenic HPV types were determined. Plasma levels were assessed at the 4-month visit for retinol, carotenoids (i.e., -, trans--, cis--carotene, -, -cryptoxanthin, lutein, zeaxanthin, trans- and cis-lycopene), tocopherols (i.e., -, -, and -tocopherol), folate and vitamin B12. Using multivariate Cox proportional hazards models, time to clearance analyses of oncogenic HPV infections were conducted for 84 women with at least one oncogenic infection at baseline. Hazard ratios (HR) were estimated for the association of HPV clearance to each nutrient tertile and to determine linear trends. Results: The likelihood of clearing an oncogenic HPV infection was significantly higher with increasing levels of trans-lycopene (p for trend, 0.025) and cis-lycopene (p for trend, 0.010). The adjusted hazard ratios of the highest tertiles of trans- and cis-lycopene were 2.79 (95% CI = 1.17–6.66) and 2.92 (95% CI = 1.28–6.63) compared with the lowest tertiles. Conclusions: Higher concentrations of trans- and cis-lycopene may reduce the time to clearance of an oncogenic HPV infection. 相似文献
92.
Anna R Giuliano Eduardo Lazcano-Ponce Luisa L Villa Roberto Flores Jorge Salmeron Ji-Hyun Lee Mary R Papenfuss Martha Abrahamsen Emily Jolles Carrie M Nielson Maria Luisa Baggio Roberto Silva Manuel Quiterio 《Cancer epidemiology, biomarkers & prevention》2008,17(8):2036-2043
Male sexual behavior influences the rates of cervical dysplasia and invasive cervical cancer, as well as male human papillomavirus (HPV) infection and disease. Unfortunately, little is known regarding male HPV type distribution by age and across countries. In samples combined from the coronal sulcus, glans penis, shaft, and scrotum of 1,160 men from Brazil, Mexico, and the United States, overall HPV prevalence was 65.2%, with 12.0% oncogenic types only, 20.7% nononcogenic types only, 17.8% both oncogenic and nononcogenic, and 14.7% unclassified infections. Multiple HPV types were detected in 25.7% of study participants. HPV prevalence was higher in Brazil (72.3%) than in the United States (61.3%) and Mexico (61.9%). HPV16 (6.5%), HPV51 (5.3%), and HPV59 (5.3%) were the most commonly detected oncogenic infections, and HPV84 (7.7%), HPV62 (7.3%), and HPV6 (6.6%) were the most commonly detected nononcogenic infections. Overall HPV prevalence was not associated with age. However, significant associations with age were observed when specific categories of HPV, nononcogenic, and unclassified HPV infections were considered. Studies of HPV type distribution among a broad age range of men from multiple countries is needed to fill the information gap internationally with respect to our knowledge of HPV infection in men. 相似文献
93.
Health education and multimedia learning: educational psychology and health behavior theory (Part 1)
When health education researchers began to investigate how individuals make decisions related to health and the factors that influence health behaviors, they referred to frameworks shared by educational and learning research. Health education adopted the basic principles of the cognitive revolution, which were instrumental in advancing the field. There is currently a new challenge to confront: the widespread use of new technologies for health education. To better overcome this challenge, educational psychology and instructional technology theory should be considered. Unfortunately, the passion to incorporate new technologies too often overshadows how people learn or, in particular, how people learn through computer technologies. This two-part article explains how educational theory contributed to the early development of health behavior theory, describes the most relevant multimedia learning theories and constructs, and provides recommendations for developing multimedia health education programs and connecting theory and practice. 相似文献
94.
B. Risendal Ph.D. J. DeZapien B.A. B. Fowler M. Papenfuss M.S. A. Giuliano Ph.D. 《Preventive medicine》1999,29(6):510
Background. American Indian women have among the highest incidence and mortality rates of cervix cancer in the United States. The incidence of cancer of the cervix among American Indians is 19.5/100,000 versus 7.8/100,000 in U.S. whites, and comparison by geographic region/tribe indicates that the rate is four to six times higher in some tribes. Papanicolaou cytological testing (Pap smear) permits the detection of cervical lesions before they become cancerous, effectively reducing the incidence of cervical cancer by 75–90%. The American Cancer Society recommends a Pap smear every year beginning at age 18 years or when sexually active, and more frequent screening in high-risk populations.Methods. A random household cross-sectional survey was conducted in Phoenix, Arizona, to assess cervical cancer screening rates among 519 adult urban American Indian women. Logistic regression was used to identify predictors of Pap smear use.Results. Three-quarters (76.1%) of urban women American Indian surveyed received a Pap smear within the past 3 years, but only 49.5% received a Pap smear within the last year. Women over age 50 years were significantly less likely to have received a recent Pap smear in comparison to younger women.Conclusions. The results of this study indicate that limited access to health care and lack of knowledge about the procedure were important barriers to Pap smear use. Improving cervix cancer screening participation rates is an important step in reducing the disease burden in this high-risk population. 相似文献
95.
抗肿瘤药物研究Ⅰ:去甲斑蝥素氨基酸衍生物的合成与抗癌活性 总被引:1,自引:0,他引:1
In order to search for new compounds with higher anti-cancer activities and lower toxicities, 19 amino acid derivatives of norcantharidin, of which 16 are unknown compounds, were designed and synthesized. Preliminary screening results revealed that 2-(syn-exo-7-oxabicyclo [2. 2. 1] heptane-2, 3-dicarboxylic imido)-N-phenyl glutaramic acid exhibited a fairly apparent inhibitory activity against human-hepatoma cells in vitro (inhibitory rate 39.4% at 0.025 μtmol/ml). 相似文献
96.
97.
p53 gene mutations in multiple myeloma are associated with advanced forms of malignancy 总被引:5,自引:3,他引:5
The frequency and type of p53 gene mutations was investigated in a series of 52 cases of multiple myeloma (MM) representative of the different clinical phases and forms of the disease (indolent, 12 cases; chronic, 24 cases; acute/leukemic, 16 cases). DNAs were analyzed for p53 gene mutations in exons 5 to 9 by polymerase chain reaction (PCR), single-strand conformation polymorphism (SSCP), and direct sequencing of PCR-amplified fragments. Point mutations were detected in 7 of 52 patients (13%) (5 at exon 8; 1 at exon 6; 1 at exon 7), and were specifically associated with the more advanced and clinically aggressive acute/leukemic forms of MM (7 of 16 [43%].) Three of the mutated cases had been evaluated at clinical presentation in earlier phases of the disease (indolent or chronic) and were found to be negative for p53 mutation. Moreover, three patients with p53 mutation had not received chemotherapy at the time of investigation. These results support the notion that the development of MM is a multistep process and suggest that alterations in the p53 gene may represent an important late event in MM tumor progression. 相似文献
98.
Nyitray AG Menezes L Lu B Lin HY Smith D Abrahamsen M Papenfuss M Gage C Giuliano AR 《The Journal of infectious diseases》2012,206(2):202-211
BACKGROUND: Few studies have assessed genital human papillomavirus (HPV) concordance and factors associated with concordance among asymptomatic heterosexual couples. METHODS: Genotyping for HPV was conducted with male and female sex partners aged 18-70 years from Tampa, Florida. Eligibility included no history of HPV-associated disease. Type-specific positive concordance (partners with ≥ 1 genotype in common) and negative concordance (neither partner had HPV) were assessed for 88 couples. Factors associated with concordance were assessed with Fisher exact tests and tests for trend. Results: Couples reported engaging in sexual intercourse for a median of 1.7 years (range, 0.1-49 years), and 75% reported being in the same monogamous relationship for the past 6 months. Almost 1 in 4 couples had type-specific positive concordance, and 35% had negative concordance for all types tested, for a total concordance of 59%. Concordance was not associated with monogamy. Type-specific positive concordance was associated with an increasing difference in partners' lifetime number of sex partners and inversely associated with an increasing difference in age. Negative concordance was inversely associated with both the couple's sum of lifetime number of sex partners and the difference in the partners' lifetime number of sex partners. Conclusions: Genital HPV concordance was common. Viral infectiousness and number of sex partners may help explain concordance among heterosexual partners. 相似文献
99.
Anic GM Lee JH Villa LL Lazcano-Ponce E Gage C José C Silva R Baggio ML Quiterio M Salmerón J Papenfuss MR Abrahamsen M Stockwell H Rollison DE Wu Y Giuliano AR 《The Journal of infectious diseases》2012,205(5):789-793
Identifying factors associated with condyloma are necessary for prevention efforts. Risk factors for incident condyloma were examined in a cohort of 2487 men from the United States, Brazil, and Mexico and were followed up every 6 months (median, 17.9 months). Factors strongly associated with condyloma were incident infection with human papillomavirus (HPV) types 6 and 11 (hazard ratio [HR], 12.42 [95% confidence interval {CI}, 3.78-40.77]), age (HR, 0.43 [95% CI, .26-.77]; 45-70 vs 18-30 years), high lifetime number of female partners (HR, 5.69 [95% CI, 1.80-17.97]; ≥21 vs 0 partners), and number of male partners (HR, 4.53 [95% CI, 1.68-12.20]; ≥3 vs 0 partners). The results suggest that HPV types 6 and 11 and recent sexual behavior are strongly associated with incident condyloma. 相似文献
100.
Temperature-dependent effects of EDTA on the membrane glycoprotein IIb- IIIa complex and platelet aggregability 总被引:6,自引:0,他引:6
In agreement with previous studies, we observed that incubation of washed human platelets with EDTA at 37 degrees C for short periods caused an irreversible loss of their aggregation response to adenosine diphosphate and markedly diminished their capacity to bind fibrinogen. AP-2 is a monoclonal antibody that reacts with a determinant specific to the glycoprotein (GP) IIb-IIIa complex. We now report that in a direct binding assay, the number of sites for AP-2 on platelets incubated with EDTA at 37 degrees C fell to approximately 30% of those present on control platelets. This effect of EDTA was not observed at room temperature. Analysis of the treated platelets by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed normal amounts of GP IIb and GP IIIa. However, studies using crossed immunoelectrophoresis with 125I-AP-2, 125I-Tab (anti-GP IIb), or 125I- AP-3 (anti-GP IIIa) in intermediate gels showed that at 37 degrees C, EDTA was inducing an irreversible change in GP IIb-IIIa complexes. A reduction in size and probable dissociation of the GP IIb-IIIa precipitate was accompanied by the appearance of precipitates having the characteristics of those given by free GP IIb and free GP IIIa and the location of a major new cathodal precipitate, which bound Tab and AP-3 but not AP-2. Membrane modifications associated with the loss of antigenic determinants on GP IIb-IIIa may explain EDTA-induced loss of platelet aggregability at 37 degrees C. 相似文献