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Handheld cellular telephone use and risk of brain cancer
Context. A relative paucity of data exist on the possible health effects of using cellular telephones. Objective. To test the hypothesis that using handheld cellular telephones is related to the risk of primary brain cancer. Design and Setting. Case-control study conducted in 5 US academic medical centers between 1994 and 1998 using a structured questionnaire. Patients. A total of 469 men and women aged 18 to 80 years with primary brain cancer and 422 matched controls without brain cancer. Main Outcome Measure. Risk of brain cancer compared by use of handheld cellular telephones, in hours per month and years of use. Results. The median monthly hours of use were 2.5 for cases and 2.2 for controls. Compared with patients who never used handheld cellular telephones, the multivariate odds ratio (OR) associated with regular past or current use was 0.85 (95% confidence interval [CI], 0.6-1.2). The OR for infrequent users (10.1 h/mo) was 0.7 (95% CI, 0.3-1.4). The mean duration of use was 2.8 years for cases and 2.7 years for controls; no association with brain cancer was observed according to duration of use (P=.54). In cases, cerebral tumors occurred more frequently on the same side of the head where cellular telephones had been used (26 vs 15 cases; P=.06), but in the cases with temporal lobe cancer a greater proportion of tumors occurred in the contralateral than ipsilateral side (9 vs 5 cases; P=.33). The OR was less than 1.0 for all histologic categories of brain cancer except for uncommon neuroepitheliomatous cancers (OR, 2.1; 95% CI, 0.9-4.7). Conclusions. Our data suggest that use of handheld cellular telephones is not associated with risk of brain cancer, but further studies are needed to account for longer induction periods, especially for slow-growing tumors wit
What Parents and Adolescent Boys Want in School Vaccination Programs in the United States
Schools are increasingly a part of vaccine provision, because of laws mandating provision of information by schools about vaccination, school entry requirements, and mass vaccination campaigns. We examined preferences for programmatic aspects of voluntary school mass vaccination programs (i.e., “vaccination days”)
Estimation of interdomain flexibility of N-terminus of factor H using residual dipolar couplings
Characterization of segmental flexibility is needed to understand the biological mechanisms of the very large category of functionally diverse proteins, exemplified by the regulators of complement activation, that consist of numerous compact modules or domains linked by short, potentially flexible, sequences of amino acid residues. The use of NMR-derived residual dipolar couplings (RDCs), in magnetically aligned media, to evaluate interdomain motion is established but only for two-domain proteins. We focused on the three N-terminal domains (called CCPs or SCRs) of the important complement regulator, human factor H (i.e. FH1-3). These domains cooperate to facilitate cleavage of the key complement activation-specific protein fragment, C3b, forming iC3b that no longer participates in the complement cascade. We refined a three-dimensional solution structure of recombinant FH1-3 based on nuclear Overhauser effects and RDCs. We then employed a rudimentary series of RDC datasets, collected in media containing magnetically aligned bicelles (disk-like particles formed from phospholipids) under three different conditions, to estimate interdomain motions. This circumvents a requirement of previous approaches for technically difficult collection of five independent RDC datasets. More than 80% of conformers of this predominantly extended three-domain molecule exhibit flexions of < 40 °. Such segmental flexibility (together with the local dynamics of the hypervariable loop within domain 3), could facilitate recognition of C3b via initial anchoring and eventual reorganization of modules to the conformation captured in the previously solved crystal structure of a C3b:FH1-4 complex
Non-Smoking Male Adolescents' Reactions to Cigarette Warnings
BackgroundThe U.S. Food and Drug Administration (FDA) is working to introduce new graphic warning labels for cigarette packages, the first change in cigarette warnings in more than 25 years. We sought to examine whether warnings discouraged participants from wanting to smoke and altered perceived likelihood of harms among adolescent males and whether these warning effects varied by age.MethodsA national sample of 386 non-smoking American males ages 11–17 participated in an online experiment during fall 2010. We randomly assigned participants to view warnings using a 2×2 between-subjects design. The warnings described a harm of smoking (addiction or lung cancer) using text only or text plus an image used on European cigarette package warnings. Analyses tested whether age moderated the warnings' impact on risk perceptions and smoking motivations.ResultsThe warnings discouraged most adolescents from wanting to smoke, but lung cancer warnings discouraged them more than addiction warnings did (60% vs. 34% were “very much” discouraged, p<.001). Including an image had no effect on discouragement. The warnings affected several beliefs about the harms from smoking, and age moderated these effects. Adolescents said addiction was easier to imagine and more likely to happen to them than lung cancer. They also believed that their true likelihood of experiencing any harm was lower than what an expert would say.ConclusionsOur findings suggest that warnings focusing on lung cancer, rather than addiction, are more likely to discourage wanting to smoke among adolescent males and enhance their ability to imagine the harmful consequences of smoking. Including images on warnings had little effect on non-smoking male adolescents' discouragement or beliefs, though additional research on the effects of pictorial warnings for this at-risk population is needed as the FDA moves forward with developing new graphic labels
Adolescent Males' Awareness of and Willingness to Try Electronic Cigarettes
Electronic cigarettes (e-cigarettes) are a new type of device that delivers vaporized nicotine without the tobacco combustion of regular cigarettes. We sought to understand awareness of and willingness to try e-cigarettes among adolescent males, a group that is at risk for smoking initiation and may use e-cigarettes as a “gateway” to smoking
How Parents Hear about HPV Vaccine: Implications for Uptake
AbstractPurposeTo examine correlates of human papillomavirus (HPV) vaccine awareness and information sources in a state requiring schools to inform parents about HPV vaccine.MethodsTelephone survey of a North Carolina population-based sample of 696 parents of females aged 10–17 years about HPV vaccine awareness and information sources (daughters' schools, healthcare provider, drug company advertisements, news stories) was conducted.ResultsOverall, 91% of parents had heard of HPV vaccine. Parents were more likely to be aware if they had household incomes of $50,000 or higher, were women, had non-Hispanic white daughters, or had daughters vaccinated against meningitis. Information sources included drug company advertisements (64%), healthcare providers (50%), news stories (50%), and schools (9%). Only parents who heard from their children's healthcare providers were more likely to initiate HPV vaccine for their daughters.ConclusionsParents had rarely heard of the vaccine through schools. The only source associated with vaccine initiation was hearing from a healthcare provider
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