龙岩市1995～2000年涂阳肺结核病人随访研究

目的：分析福建省龙岩市结核病控制五年效果。为结核病控制可持续发展提供技术政策依据。方法：收集并分析1995年-2000年福建省龙岩市肺结核月报表和年报表及有关资料，采用队列分析方法对登记治疗管理的初，复治涂阳肺结核病人进行分析。结果：1995年-2000年涂阳肺结核病人发现率从4.9/10万上升到22.7/10万；初治涂阳治愈率从63.4%上升到95.8%；复治涂阳病人治愈率从50%上升到85.6%。结论：涂阳肺结核病人的高发现率和高治愈率是因为1999年开始实施结核病归口管理和DOTS策略，应以持续发燕尾服。     

实施现代结核病控制策略对传染性肺结核患者发现与治疗效果的影响

目的：分析实施DOTS策略对传染性肺结核病例发现与治疗效果的影响。方法：通过对1995—2000年分批实施的卫生部加强与促进结核病控制项目、WHO西太区结核病控制项目及福建省结核病控制项目资料进行分析。结果涂阳病例新登记率由1995年的6．3／10万提高到2000年的19．0／10万，涂片阳性占活动性病例比例由21．5％提高到37．4％，新发涂阳病例治愈率由80．7％提高到89．2％，病例丢失率由7．3％下降到2．7％，治疗失败率由6．9％下降到1．4％。流动人口传染性肺结核病例治愈率仅59．7％。结论：实施DOTS策略，重视流动人口结核病治疗管理，提高涂阳病例发现率、治愈率，减少病例丢失和治疗失败，有效控制结核病。     

Estimating HIV incidence in voluntary counseling and testing clients in Uganda (1992-2003)

OBJECTIVES: To estimate HIV incidence from first-time testers among voluntary counseling and testing (VCT) clients in Uganda. METHODS: Data on 203,000 VCT clients tested from 1992 through 2003 were adjusted for temporal changes in the testing population. Differential mortality rates by HIV status were used to derive expected prevalence at future times from baseline prevalence within 5-year birth cohorts. Incidence was computed as the proportion of HIV-uninfected persons who seroconverted divided by the proportion negative at baseline. RESULTS: Annual HIV incidence per 100 uninfected persons increased from 0.9 (95% confidence interval [CI]: 0.8 to 1.1) in 1993 to 2.3 (95% CI: 2.2 to 2.5) in 2003 (chi test for trend, P < 0.001). Prevalence decreased from 23% to 13% in 1999 to 2000 and increased to 15% in 2003. Women had a higher incidence. Peak incidence shifted to older age groups over time. CONCLUSIONS: Estimating incidence from routine data presents a practical way of tracking HIV incidence and is a useful tool in targeting and evaluating the impact of prevention programs. Our analysis reveals a new phase of the HIV epidemic in Uganda: decreasing prevalence and increasing incidence, especially among middle-aged persons. These findings support the need for intensified prevention interventions among middle-aged persons in Uganda.     

Exposure to Community Violence and Sexual Behaviors Among African American Youth: Testing Multiple Pathways

African American youth bear a disproportionate burden of sexually transmitted infections. A growing number of studies document that youth exposure to community violence and sexual behaviors are highly correlated. Despite such growing evidence, only a few studies have empirically tested conceptually driven pathways that may account for such relationships. This study seeks to address that gap by exploring multiple pathways linking exposure to community violence and youth sexual behaviors. Using an existing sample of 563 African American youth attending high school, we examined whether possible links between exposure to community violence and sexual activity, sexual risk behaviors were mediated by aggression, low student-teacher connectedness, and negative peer norms. Major findings indicated indirect relationships between exposures to community violence and both sexual activity and risky sex, mediated by aggression and negative peer norms with no significant differences based on gender or socioeconomic status. Overall findings also indicated a significant indirect effect of aggression to risky sex via negative peer norms and from community violence to risky peer norms via aggression. By illuminating ways that community violence, aggression, peer norms, and sexual behaviors are dynamically interrelated, these findings have significant implications for future research and intervention initiatives aimed at addressing the different pathways.     

Unresolved questions regarding human hereditary deafness

Human hearing loss is a common neurosensory disorder about which many basic research and clinically relevant questions are unresolved. This review on hereditary deafness focuses on three examples considered at first glance to be uncomplicated, however, upon inspection, are enigmatic and ripe for future research efforts. The three examples of clinical and genetic complexities are drawn from studies of (i) Pendred syndrome/DFNB4 (PDS, OMIM 274600), (ii) Perrault syndrome (deafness and infertility) due to mutations of CLPP (PRTLS3, OMIM 614129), and (iii) the unexplained extensive clinical variability associated with TBC1D24 mutations. At present, it is unknown how different mutations of TBC1D24 cause non‐syndromic deafness (DFNB86, OMIM 614617), epilepsy (OMIM 605021), epilepsy with deafness, or DOORS syndrome (OMIM 220500) that is characterized by d eafness, o nychodystrophy (alteration of toenail or fingernail morphology), o steodystrophy (defective development of bone), mental r etardation, and s eizures. A comprehensive understanding of the multifaceted roles of each gene associated with human deafness is expected to provide future opportunities for restoration as well as preservation of normal hearing.     

A proposal for applying molecular markers as an aid to identifying potential cases of imported tuberculosis in immigrants

In recent years, the percentage of tuberculosis (TB) cases in immigrants in Spain has increased markedly. In this context, discrimination between cases with potentially imported TB and cases likely to have acquired it by recent transmission after arrival is a basic issue. In this study, we evaluated molecular markers to obtain information on the geographic origin of Mycobacterium tuberculosis (MTB) strains and to determine whether they could help to identify imported TB cases. We analyzed the pks15/1 gene, spoligotype, and MIRU locus 24 in 168 MTB isolates from immigrants of 32 nationalities and from a selection of autochthonous cases. In non-Asian immigrants we could not detect major differences with the autochthonous cases. For the Asian cases, we found some specific features for these markers. pks15/1 was intact in 69% of the Asian patients, but this gene had a 7-bp deletion in all non-Asian and Spanish (non-Beijing) cases. The spoligotype-defined lineages EAI and CAS, and the allele with two repetitions in MIRU locus 24 was found exclusively among Asian immigrants. The analysis of certain bacterial molecular markers could help to discriminate between potentially imported TB cases and those more probably acquired in the host country.     

Identification of 2,3-dihydroxybenzoic acid as a Brucella abortus siderophore.

Brucella abortus grown in low-iron medium or in the presence of iron chelators [ethylenediamine-di(o-hydroxyphenylacetic acid) and 2,2-dipyridyl] showed reduced cell yields and released a material positive in chemical and biological assays for catechols. This material was purified from culture fluids of B. abortus 2308 by chromatography on agarose-iminodiacetic acid-Fe3+ and identified as 2,3-dihydroxybenzoic acid (2,3-DHBA) by thin-layer chromatography, paper electrophoresis, and UV-visible nuclear magnetic resonance and mass spectroscopy. No other major catechols were observed at different stages of growth, and 2,3-DHBA was also produced upon iron limitation by representative strains of B. abortus biotypes 1, 5, 6, and 9. Both synthetic 2,3-DHBA and the natural catechol relieved the growth inhibition of B. abortus 2308 by ethylenediamine-di(o-hydroxyphenylacetic acid), and 2,3-DHBA promoted 55Fe uptake by B. abortus 2308 by an energy-dependent mechanism. Two other monocatechols tested, 2,3-dihydroxybenzoyl-Ser and 2,3-dihydroxybenzoyl-Gly, also promoted 55Fe uptake. More complex catechol siderophores (agrobactin and enterobactin), hydroxamate siderophores (aerobactin, ferrichrome, and deferriferrioxamine mesylate [Desferal]), and an EDTA-related siderophore (rhizobactin) failed to mediate 55Fe uptake. B. abortus cells grown in low-iron medium or in medium with iron had similar rates of iron uptake when supplied with 55Fe-2,3-DHBA, and the release of 2,3-DHBA under iron starvation was not associated with the expression of new outer membrane proteins. These results suggest an uptake system in which only the synthesis of the siderophore is regulated by the iron available for growth.     

Hyperlipidemia, hypercoagulability, and accelerated thrombosis: studies in congenitally hyperlipidemic rats and in rats and monkeys with induced hyperlipidemia

Inbred Carworth Farms Nelson (CFN) congenitally hyperlipidemic rats had significantly shorter coagulation and prothrombin times and higher levels of coagulation factors, II, V, VII, VIII, and X than did controls. Conversely, congenitally hypolipidemic rats of the same strain had significantly longer coagulation and prothrombin times and lower levels of factors II, V, VII, X and XII and of blood platelets than did controls. A loop-shaped polyethylene cannula was inserted into the aorta to assess the potential for thrombosis. The hyperlipidemic group obstructed this significantly faster and the hypolipidemic group slower than did the controls. Normal CFN rats made hypertensive by unilateral renal artery clip developed hypertension together with significantly elevated serum cholesterol and factor VII and X levels. Rhesus monkeys with diet-induced hyperlipidemia showed shorter prothrombin times and higher factor X levels than did controls on normal diet. By selective breeding, two groups of squirrel monkeys were obtained. Both groups had similar serum cholesterol levels on a normal diet but one group (hyperresponders) showed higher serum cholesterol levels on a cholesterol-containing diet than did the other (hyporesponder) group. Both groups showed significantly elevated levels of factors II, V, VII, IX and X on a cholesterol-containing diet. There was good correlation between the levels of many coagulation factors and serum cholesterol in both rats and monkeys. If thrombosis is important in the genesis of atherosclerosis, these findings could indicate that elevation of plasma lipids may play a role, via the coagulation pathway, in the production of human vascular disease.