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1.
We read with interest the commentary by Skeldon and Dijk about our article “Weekly, seasonal and chronotype-dependent variation of dim light melatonin onset.” The discussion points raised by Skeldon and Dijk are currently among the most hotly debated in human circadian science. What external factors determine human phase of entrainment? How great is the contribution of natural versus artificial light and sun time versus social time? Our intra-individual data add to the still limited evidence from field studies in this matter. In their commentary, Skeldon and Dijk formulate two either-or hypotheses, postulating that humans entrain either solely to the natural light-dark cycle (sun time referenced by midday) (H1) or solely to the light selected by local clock time and social constraints (H2). Neither hypothesis accounts for the effect of season on human light exposure. We interpreted our findings along more complex lines, speculating that the 1-h earlier melatonin rise in summer found in our sample is likely the combined result of daylight saving time (DST)-induced behavioral advances and a stronger natural zeitgeber in summer (light exposure determined by social and seasonal factors, Horiginal). Here, we show how the criticism by Skeldon and Dijk is based on two sentences quoted out of context (misrepresenting our hypothesis as H1) and that their hypothesis H2 leaves out important seasonal components in light exposure. 相似文献
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Deepti Bettampadi Luisa L. Villa Eduardo L. Ponce Jorge Salmeron Bradley A. Sirak Martha Abrahamsen Julie A. Rathwell Richard R. Reich Anna R. Giuliano 《International journal of cancer. Journal international du cancer》2020,146(11):3026-3033
Incidence of human papillomavirus (HPV) attributable oropharyngeal cancers (OPCs) has been increasing globally, especially among men in high-income countries. There is a lack of studies comparing oral HPV prevalence by age and country among healthy men. The purpose of our study was to assess oral HPV prevalence by country and age. Participants of the HPV Infection in Men Study (HIM), a cohort of 3,098 healthy men from São Paulo, Brazil, Cuernavaca, Mexico and Tampa, USA, were studied. Oral HPV prevalence and type distribution were assessed using the SPF10 PCR-DEIA-LiPA25 system. The prevalence of any HPV in Brazil, Mexico and the US was 8.7% (95% CI: 7.1%, 10.4%), 10.0% (95% CI: 8.3%, 12.1%) and 7.6% (95% CI: 5.9%, 9.5%), respectively, while the prevalence of high-risk HPV was 5.3% (95% CI: 4.1%, 6.7%), 7.3% (95% CI: 5.7%, 9.0%) and 5.4% (95% CI: 4.0%, 7.0%), respectively. No significant differences in prevalence of grouped HPV types were observed by country despite significant differences in sexual behaviors. However, the age-specific prevalence of oral HPV differed by country. Brazilian (6.0% [95% CI: 3.4%, 9.7%]) and Mexican (9.2% [95% CI: 5.6%, 14.0%]) participants had peak high-risk HPV prevalence among men aged 41–50 years whereas the US participants had peak prevalence at ages 31–40 years (11.0% [95% CI: 6.4%, 17.3%]). In conclusion, oral HPV prevalence was low with no difference in overall prevalence observed by country. Factors associated with the differences in oral HPV age-patterning by country and sexual orientation require further study. 相似文献
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Esther M. John Amanda I. Phipps Lisa M. Hines Jocelyn Koo Sue A. Ingles Kathy B. Baumgartner Martha L. Slattery Anna H. Wu 《International journal of cancer. Journal international du cancer》2020,147(7):1808-1822
We pooled multiethnic data from four population-based studies and examined associations of menstrual and reproductive characteristics with breast cancer (BC) risk by tumor hormone receptor (HR) status [defined by estrogen receptor (ER) and progesterone receptor (PR)]. We estimated odds ratios and 95% confidence intervals using multivariable logistic regression, stratified by age (<50, ≥50 years) and ethnicity, for 5,186 HR+ (ER+ or PR+) cases, 1,365 HR− (ER− and PR−) cases and 7,480 controls. For HR+ BC, later menarche and earlier menopause were associated with lower risk in non-Hispanic whites (NHWs) and Hispanics, and higher parity and longer breast-feeding were associated with lower risk in Hispanics and Asian Americans, and suggestively in NHWs. Positive associations with later first full-term pregnancy (FTP), longer interval between menarche and first FTP and shorter time since last FTP were limited to younger Hispanics and Asian Americans. Except for nulliparity, reproductive characteristics were not associated with risk in African Americans. For HR− BC, lower risk was associated with later menarche, except in African Americans and older Asian Americans and with longer breast-feeding in Hispanics and Asian Americans only. In younger African Americans, HR− BC risk associated with higher parity (≥3 vs. 1 FTP) was increased fourfold in women who never breast-fed, but not in those with a breast-feeding history, suggesting that breast-feeding may mitigate the adverse effect of higher parity in younger African American women. Further work needs to evaluate why menstrual and reproductive risk factors vary in importance according to age and ethnicity. 相似文献
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Anahi González-Acevedo Juan A. García-Salas Jaime Gosálvez José Luis Fernández Martha I. Dávila- Rodríguez Ricardo M. Cerda-Flores 《Toxicology mechanisms and methods》2016,26(1):61-66
The concentrations of recognized or suspected genotoxic and carcinogenic agents found in the air of large cities and, in particular, developing countries, have raised concerns about the potential for chronic health effects in the populations exposed to them. The biomonitoring of environmental genotoxicity requires the selection of representative organisms as “sentinels,” as well as the development of suitable and sensitive assays, such as those aimed at assessing DNA damage. The aim of this study was to evaluate DNA damage levels in erythrocytes from Columba livia living in the metropolitan area of Monterrey, Mexico, compared with control animals via comet assay, and to confirm the results via Micronuclei test (MN) and DNA breakage detection–fluorescence in situ hybridization (DBD–FISH). Our results showed a significant increase in DNA migration in animals from the area assayed compared with that observed in control animals sampled in non-contaminated areas. These results were confirmed by MN test and DBD–FISH. In conclusion, these observations confirm that the examination of erythrocytes from Columba livia via alkaline comet assay provides a sensitive and reliable end point for the detection of environmental genotoxicants. 相似文献
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Jenny G. Turcott Eva Juárez-Hernández Martha De la Torre-Vallejo Karla Sánchez-Lara Julissa Luvian-Morales 《Nutrition and cancer》2016,68(2):241-249
We evaluated the effects of cisplatin and paclitaxel on taste acuity and their associations with nutritional and health-related quality of life (HRQL) in patients with advanced non-small-cell lung cancer (NSCLC). Forty chemotherapy (CT)-naïve patients were assessed at baseline and after two cycles of paclitaxel and cisplatin. The taste evaluation was performed using a rinsing technique to identify detection and recognition thresholds (DT and RT) of bitter, sweet, and umami tastes. At baseline, 37.5% of the patients reported dysgeusia. After CT, the patients showed lower medians DT (p = 0.017) and RT (p = 0.028) for umami taste. These decreases were associated with clinical neuropathy, worse HRQL, and a tendency toward increased appetite loss. Additionally, CT did not significantly reduce the median DT for sweet (p = 0.09), which is associated with lower intake of protein (p = 0.015), animal protein (p = 0.010), fat (p = 0.004), and iron (p = 0.047). CT decreased the median DT for bitter (p = 0.035); however, this decrease was not associated with nutritional parameters or with HRQL. Sensitivity to taste increased with paclitaxel and cisplatin CT, making foods more unpleasant, and it was associated with neuropathy, worse HRQL, and reduced nutrient intake in advanced NSCLC patients. The protocol was registered at clinicaltrials.gov (NCT01540045). 相似文献
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