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Background. Rapid skin warming and prompt correct medical treatment lead to dramatic improvement in patients with peripheral capillary‐related damage, such as injuries, Raynaud disease and frostbite. Aim. To characterize a novel composite, NXCL‐4950, for use in a cosmetic lotion. Methods. The effects of NXCL‐4950 on enhancing skin blood flow, skin temperature warming, and expansion of peripheral blood vessels and scalp microvessels were investigated. Results. Monitoring by laser Doppler perfusion imaging and thermal imaging showed that application of NXCL‐4950 to the hands increased skin blood flow and temperature relative to the control (or placebo) group. For the 20 participants with a high Raynaud Condition Score, application of NXCL‐4950 to the skin resulted in a mean increase of 215.53% in microvessel diameter and mean increase of 164.96% in the speed of blood flow. When NXCL‐4950 was applied to the scalp, the microvessels around the hair roots were clearly visible after 20 min. Conclusion. NXCL‐4950 is a potential candidate for enhancing peripheral skin temperature, and might be useful in the treatment of capillary‐related disorders.  相似文献   
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Epidemiologic studies have linked the consumption of red meat and the consumption of highly browned meats containing high levels of heterocyclic aromatic amines (HCAs) to increased risk of colorectal cancer or polyps. The present study determined the effects of long‐term feeding of beef‐containing diets with low and high levels of HCAs (in the context of a low or high beef tallow diet) on a standard 1,2‐dimethylhydrazine (DMH)‐induced colon tumorigenesis protocol. Very lean beef was cooked by a variety of methods at different temperatures, and the levels of the major HCAs (2‐amino‐3,8‐dimethylimidazo[4,5‐f]quinoxaline, 2‐amino‐3,4,8‐trimethylimidazo[4,5‐f]quinoxaline, and 2‐amino‐l‐methyl‐6‐phenylimidazo[4,5‐f]pyridine) were measured by high‐performance liquid chromatogra‐phy. Diets incorporating beef containing low or high levels of HCAs were fed for 12 weeks, during which DMH was administered to induce colon tumors, followed by various dietary regimens as promotional stimuli. Feeding of a beef diet high in HCAs resulted in more DMH‐induced colon adenocarcinomas, but only in the context of a low‐fat diet. The high‐HCA diets increased stomach tumors in all DMH‐treated rats. An apparent interaction of high HCA with a high fat level reduced the colon tumor incidence and tumor numbers in those diets containing both factors. These results support the epidemiologic data linking well‐cooked meat to increased risk for colon and stomach cancer, but the role of dietary fat level remains puzzling.  相似文献   
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Organochlorine pesticides and brominated flame retardants, such as tetrabromobisphenol A and polybrominated diphenyl ethers, pose an environmental hazard owing to their persistence, low solubility and estrogenic effects, and concerns have been raised regarding their effects on aquatic biota. In the present study, zebrafish embryos and larvae were used as a model to investigate the sublethal and lethal effects of three different organochlorine pesticides, namely methoxychlor, endosulfan and heptachlor, as well as the flame retardant tetrabromobisphenol A, and its precursor compound bisphenol A. Preliminary data for chemical exposure tests were obtained by determining the 96 h median effective concentration EC50 (hatching rate) and 96 h median lethal concentration LC50. Quantitative polymerase chain reaction was used to investigate the gene expression levels of the biomarker vitellogenin (vtg1) after 96 h exposures to 10, 25, 50 and 75% of the 96 h EC50 value for embryos and 96 h LC50 value for larvae. The use of vtg1 mRNA induction in zebrafish embryos and larvae was found to be a sensitive biomarker of exposure to these organic compounds, and was helpful in elucidating their adverse effects and setting water quality guidelines. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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M. genitalium is a reemerging microorganism, responsible for sexually transmissible infections (STIs), with prevalence which varies depending on the country and population group studied. We report here M. genitalium prevalence among the specimens received for STI diagnosis in our routine microbiological laboratory in the university hospital in Marseille, France. We tested 4 624 samples from 3 793 patients using qPCR for M. genitalium, C. trachomatis, N. gonorrheae, T. pallidum. Of these samples, 528 (13.6%) patients were tested positive for at least one pathogen and 126 (3.3%) were positive for M. genitalium. M. genitalium is the second most prevalent micro‐organism detected in women after C. trachomatis (10.4%) and the third most prevalent in men after C. trachomatis (5.1%) and N. gonorrhoeae (4.4%). We observed no significant differences between the prevalence of M. genitalium in vaginal, urethral and urine specimens (p = 0.9). Prevalence of M. genitalium is significantly higher in patients aged between 10–30 years (4.1%) compared to those aged between 30 and 50 years (2.7%) (p = 0.02, RR = 1.54 [1.06–2.24]) and patients over 50 years of age (1.1%) (p = 0.003, RR= 3.98 [1.47–10.8]). M. genitalium is a common agent of STI, therefore we suggest that this micro‐organism should be systematically tested during chronic, recurrent, or antibiotic resistant genital infections and in populations at high‐risk of STIs.  相似文献   
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