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We investigated the association of protein Z (PZ) promoter (rs3024718, rs3024719, and rs3024731) and intron (rs3024735; G79A) SNPs with sickle cell disease (SCD) vaso-occlusive crisis (VOC). Study subjects included 239 SCD patients with VOC and 138 pain-free SCD control patients. PZ genotyping was done by allelic discrimination (real-time PCR) assays. The minor allele frequency of rs3024718 (P=0.03), rs3024719 (P=0.02), rs3024731 (P<0.001), and rs3024735 (P<0.001) were higher in VOC patients than control SCD patients. Significant differences in the distribution of rs3024731 (P=0.028) and rs3024735 (P=0.045) genotypes were seen between VOC and steady-state SCD patients. This association remained significant after adjusting for gender, HbS, and HbF. Four-locus (rs3024718/rs3024719/rs3024731/rs3024735) PZ haplotypes analysis demonstrated increased frequency of GAAA (P=0.024), AGAA (P=0.011), and GGTG (P=0.002), and reduced frequency of AGTG haplotype (P=0.001) in VOC than in steady-state control patients, thereby conferring disease susceptibility and protective nature to these haplotypes, respectively. Of these, only AGTG (P(c)=0.001) and GGTG (P(c)=0.018) remained significant after applying the Bonferroni correction. In conclusion, specific PZ variants and haplotypes are significantly associated with SCD VOC.  相似文献   
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Given its association with Epstein-Barr virus (EBV), there is considerable interest in assessing the impact of prophylactic anti-viral therapy on post-transplant lymphoproliferative disorder (PTLD). A recently completed multi center case-control study assessed the impact of immunosuppressive therapy on PTLD risk among renal transplant patients and collected information on the use of anti-viral therapy. Biopsy-confirmed PTLD cases (n = 100) were matched to 375 controls by center, date of transplant, and age. Data were collected on immunosuppression and rejection therapies, demographics, pre-transplant viral status, number of rejections, and anti-viral use. With adjustment for known risk factors, prophylactic anti-viral use was associated with up to 83% reduction in the risk of PTLD, depending on the anti-viral agent. These results were stronger for the first year post-transplant. For every 30 days of ganciclovir treatment, risk of PTLD during the first year was lower by 38% (Odds Ratio [OR]= 0.62; 95% confidence interval [CI]= 0.38-1.0); acyclovir effects were less striking (OR = 0.83; 95% CI = 0.59-1.16). Anti-viral therapy appears to play a role in reducing the risk of PTLD in renal transplant patients. Ganciclovir may be more potent than acyclovir.  相似文献   
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The purpose of the present investigation was to determine the relationship between oral parafunctions and the development of temporomandibualr disorders (TMD). A group of 1,976 children aged 3-15 years old, were randomly selected and underwent an examination that consisted of palpation and assessment of the temporomandibular joints and associated muscles for tenderness and joint sounds. Maximum vertical opening and deviation during jaw opening were also recorded. The parents were requested to complete a questionnaire contained questions regarding symptoms of TMD and history of oral parafunctions. Results showed significant correlations between cheek biting, nail biting, bruxism, thumb sucking and most of TMD signs and symptoms. The results of the study support the concept that oral parafunctions have a significant role in the aetiology of TMD and should be tackled by the paediatric dentists to minimise their effects on the stomatological system.  相似文献   
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Burning charcoal is normally placed atop the tobacco to smoke the narghile waterpipe. We investigated the importance of charcoal as a toxicant source in the mainstream smoke, with particular attention to two well-known charcoal emissions: carbon monoxide (CO) and polyaromatic hydrocarbons (PAH). CO and PAH yields were compared when a waterpipe was machine smoked using charcoal and using an electrical heating element. The electrical heating element was designed to produce spatial and temporal temperature distributions similar to those measured using charcoal. With a popular type of ma'assel tobacco mixture, and using a smoking regimen consisting of 105 puffs of 530ml volume spaced 17s apart, it was found that approximately 90% of the CO and 75-92% of the 4- and 5-membered ring PAH compounds originated in the charcoal. Greater than 95% of the benzo(a)pyrene in the smoke was attributable to the charcoal. It was also found that the relative proportions of individual PAH species, the "PAH fingerprint", of the mainstream smoke were highly correlated to those extracted from the unburned charcoal (R(2)>0.94). In contrast, there was no correlation between the PAH fingerprint of the electrically heated and charcoal-heated conditions (R(2)<0.02). In addition to inhaling toxicants transferred from the tobacco, such as nicotine, "tar", and nitrosamines, waterpipe smokers thus also inhale large quantities of combustion-generated toxicants. This explains why, despite the generally low temperatures attained in the narghile tobacco, large quantities of CO and PAH have been found in the smoke.  相似文献   
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