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51.
Arif JM; Gairola CG; Glauert HP; Kelloff GJ; Lubet RA; Gupta RC 《Carcinogenesis》1998,19(8):1515-1517
The present study investigated the effects of dietary oltipraz on cigarette
smoke-related lipophilic DNA adduct formation. Female Sprague- Dawley rats
were exposed daily to sidestream cigarette smoke in a whole- body exposure
chamber 6 h/day for 4 consecutive weeks. One group of rats was maintained
on control diet while another group received the same diet supplemented
with either a low (167 p.p.m.) or high (500 p.p.m.) dose of oltipraz,
starting 1 week prior to initiation of smoke exposure until the end of the
experiment. Analysis of lipophilic DNA adducts by the nuclease P1-mediated
32P-post-labeling showed up to five smoke-related adducts. Adduct no. 5
predominated in both the lung and the heart while adduct nos 3 and 2
predominated in the trachea and bladder, respectively. Quantitative
analysis revealed that the total adduct level was the highest in lungs
(270+/-68 adducts/10(10) nucleotides), followed by trachea (196+/-48
adducts/10(10) nucleotides), heart (141+/-22 adducts/10(10) nucleotides)
and bladder (85+/-16 adducts/10(10) nucleotides). High dose oltipraz
treatment reduced the adduct levels in lungs and bladder by >60%, while
the reduction in lungs in the low-dose group was approximately 35%. In
trachea, the effect of low and high dietary oltipraz on smoke DNA adduction
was equivocal, while smoke-related DNA adducts in the heart were minimally
inhibited by high-dose oltipraz. In a repeat experiment that employed a
3-fold lower dose of cigarette smoke, oltipraz (500 p.p.m.) was found to
inhibit the formation of DNA adducts in rat lungs and trachea by 80 and
65%, respectively. These data clearly demonstrate a high efficacy of
oltipraz in inhibiting the formation of cigarette smoke-induced DNA adducts
in the target tissues.
相似文献
52.
Janet Li Paul Roche Jenean Spencer Ivan Bastian Amanda Christensen Mark Hurwitz Anastasios Konstantinos Vicki Krause Moira McKinnon Avner Misrachi Graham Tallis Justin Waring 《Communicable diseases intelligence》2004,28(4):464-473
The National Notifiable Disease Surveillance System (NNDSS) received 982 tuberculosis (TB) notifications in 2003, of which 947 were new cases, 33 were relapses and two were cases with unknown history. The incidence of TB in Australia has remained at a stable rate since 1985 and was 4.9 cases per 100,000 population in 2003. The high-incidence groups remain people born overseas and Indigenous Australians at 19.9 and 8.7 cases per 100,000 population, respectively. By contrast the incidence in non-Indigenous Australians was 0.9 per 100,000. Comparison of the 2003 TB notification data against the performance indicators set by National Tuberculosis Advisory Committee highlights that enhanced TB control measures should be considered among these high-risk groups. 相似文献
53.
Sarah A McKinnon Kathleen M O'rourke Sharon E Thompson Jessica H Berumen 《The Journal of adolescent health》2004,34(1):88-93
PURPOSE: To determine the rates of alcohol consumption and alcohol-related risk behaviors among a sample of high school students living on the U.S.-Mexico border, as well as to investigate factors associated with alcohol use among this population. METHODS: A self-administered anonymous questionnaire was administered to students in grades 9-12 during Fall and Spring semesters of 2001 (n = 1366; 639 males and 722 females) in 16 high schools in a community along the U.S.-Mexico border. The questionnaire addressed demographic factors, alcohol consumption, and alcohol-related behaviors. Surveys were completed by Chi-square tests for homogeneity of the odds ratio and logistic regression models were used to identify factors significantly associated with the outcome variables. RESULTS: Rates of binge drinking (45%), drinking and driving (19%), and riding with a driver who had been drinking (46%) were higher for our study population when compared with state and national rates. Students who consumed alcohol were more likely to report alcohol-related problems and lower academic grades. Drinking while in Mexico was significantly associated with binge drinking (OR = 6.44), drinking and driving (OR = 5.39), and riding with a driver who has been drinking (OR = 3.12). CONCLUSIONS: The high rates of alcohol risk behaviors among students living on the U.S.-Mexico border underscore the need to develop and implement culturally appropriate prevention programs that address alcohol consumption in Mexico, particularly in terms of students driving back home. 相似文献
54.
55.
RA D. Wüstenberg 《Der Gyn?kologe》2006,39(10):824-828
Some of the girls who live in Germany and have Muslim parents are threatened by female genital mutilation. This report describes the kinds and medical consequences of female genital mutilation as well as the criminal judgement. Female genital mutilation is considered as dangerous bodily harm, not as grievous bodily harm. Consent does not justify the infringement of rights. The argument that Islam justifies the infringement of rights is irrelevant by law. The human right of bodily intactness has priority over the right of religious freedom. Finally the legal regulations about dealing with personal data are presented. A legal compulsory registration still does not exist. 相似文献
56.
The HIV pandemic has disproportionately impacted sub-Saharan Africa and Southern Africa in particular. The concurrent presence of overlapping epidemic drivers likely underpins how and why the HIV epidemic is so explosive in this region, with implications for understanding approaches to reduce transmission. In this review, we discuss the relative contribution and interaction between epidemic drivers in the Southern African context, including factors both distally and proximally associated with the likelihood and degree of exposure to HIV and factors that increase the probability of transmission when exposure occurs. In particular, we focus on young women as a key population in need of HIV prevention and highlight factors that increase their risk on several levels. 相似文献
57.
Donald S. Strassberg Ryan K. McKinnon Michael A. Sustaíta Jordan Rullo 《Archives of sexual behavior》2013,42(1):15-21
Recently, a phenomenon known as sexting, defined here as the transfer of sexually explicit photos via cell phone, has received substantial attention in the U.S. national media. To determine the current and potential future impact of sexting, more information about the behavior and the attitudes and beliefs surrounding it must be gathered, particularly as it relates to sexting by minors. The present study was designed to provide preliminary information about this phenomenon. Participants were 606 high school students (representing 98 % of the available student body) recruited from a single private high school in the southwestern U.S. Nearly 20 % of all participants reported they had ever sent a sexually explicit image of themselves via cell phone while almost twice as many reported that they had ever received a sexually explicit picture via cell phone and, of these, over 25 % indicated that they had forwarded such a picture to others. Of those reporting having sent a sexually explicit cell phone picture, over a third did so despite believing that there could be serious legal and other consequences attached to the behavior. Given the potential legal and psychological risks associated with sexting, it is important for adolescents, parents, school administrators, and even legislators and law enforcement to understand this behavior. 相似文献
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60.
Maria Fatima Falangola Xingju Nie Ralph Ward Emilie T. McKinnon Siddhartha Dhiman Paul J. Nietert Joseph A. Helpern Jens H. Jensen 《NMR in biomedicine》2020,33(9)
The 3×Tg‐AD mouse is one of the most studied animal models of Alzheimer's disease (AD), and develops both amyloid beta deposits and neurofibrillary tangles in a temporal and spatial pattern that is similar to human AD pathology. Additionally, abnormal myelination patterns with changes in oligodendrocyte and myelin marker expression are reported to be an early pathological feature in this model. Only few diffusion MRI (dMRI) studies have investigated white matter abnormalities in 3×Tg‐AD mice, with inconsistent results. Thus, the goal of this study was to investigate the sensitivity of dMRI to capture brain microstructural alterations in 2‐month‐old 3×Tg‐AD mice. In the fimbria, the fractional anisotropy (FA), kurtosis fractional anisotropy (KFA), and radial kurtosis (K┴) were found to be significantly lower in 3×Tg‐AD mice than in controls, while the mean diffusivity (MD) and radial diffusivity (D┴) were found to be elevated. In the fornix, K┴ was lower for 3×Tg‐AD mice; in the dorsal hippocampus MD and D┴ were elevated, as were FA, MD, and D┴ in the ventral hippocampus. These results indicate, for the first time, dMRI changes associated with myelin abnormalities in young 3×Tg‐AD mice, before they develop AD pathology. Morphological quantification of myelin basic protein immunoreactivity in the fimbria was significantly lower in the 3×Tg‐AD mice compared with the age‐matched controls. Our results demonstrate that dMRI is able to detect widespread, significant early brain morphological abnormalities in 2‐month‐old 3×Tg‐AD mice. 相似文献