Direct oral questions to blood donors: the impact on screening for human immunodeficiency virus

BACKGROUND: In December 1990, the Food and Drug Administration recommended that all United States blood centers implement a policy of asking prospective donors direct oral questions (DOQs) about human immunodeficiency virus (HIV) risk behaviors to increase the safety of the blood supply. STUDY DESIGN AND METHODS: To evaluate the impact of the DOQ policy, HIV-related deferral and HIV seroprevalence data were analyzed at four American Red Cross blood centers for the year before the policy change and the year after. An epidemiologic analysis with stratification was conducted, including the calculation of odds ratios (OR) and 95-percent CIs. RESULTS: Two of the four blood centers showed an overall significant increase in HIV-related deferral after implementation of the DOQ policy: OR = 4.04, (95% CI = 3.41, 4.76); OR = 2.93, (95% CI = 2.67, 3.21). The increase in HIV-related deferral was higher for women. HIV seroprevalence decreased at all four centers, including the two that did not see an increase in HIV-related deferrals. Seroprevalence declined by 14 percent in the two centers with increases in HIV-related deferral, which was neither significant nor attributable to DOQs. CONCLUSION: Given that HIV antibody screening cannot detect HIV-seronegative (but infectious) "window-period" donations, the deferral of at-risk donors may offer some additional protection to the blood supply. However, evidence was not found of an increase in safety of the blood supply as measured by HIV seroprevalence.     

苯巴比妥诱导下大鼠肝微粒体药酶活性与膜流动性变化的相关性

本文用ANS和DPH为荧光探剂,研究苯巴比妥(PB)诱导下大鼠肝微粒体膜脂区流动性与膜药酶活性变化的相关性。结果表明,经PB诱导后在增加肝微粒体蛋白质含量,P-450含量及NADPH-细胞色素C还原酶等酶活性的同时,肝微粒体膜流动性明显增大,且膜深层流动性的增大与膜氨基比林N-脱甲基酶、细胞色素C还原酶活性增加有明显的直线正相关。膜胆固醇/碑脂比值明显降低。此结果提示,肝微粒体膜流动性的适当增大与PB增加单胺氧化酶系统活性之间可能存在着某种联系。     

Epstein-Barr virus: Biology and disease

Epstein—Barr virus is a human herpes virus which, whilst found as a widespread asymptomatic infection, is also associated with certain tumours of lymphoid and epithelial origin including Burkitt's lymphoma (BL), immunoblastic lymphoma (IBL), Hodgkin's Disease (HD) and nasopharyngeal carcinoma (NPC). A unique characteristic of EBV is its ability to infect and transform primary resting B lymphocytes in vitro into permanently growing lymphoblastoid cell lines (LCLs); this effect is associated with constitutive expression of a limited set of viral genes. Interestingly, the pattern of EBV gene expression observed in LCLs in vitro is also a feature of IBLs, a tumour associated with immunosuppression. The other EBV associated tumours display a more restricted pattern of EBV latent protein expression. B cell lines can be activated in vitro into the virus replicative cycle, where a large number of viral genes associated with EBV DNA replication and virus assembly are synthesised. Whilst EBV can be detected in throat washings from seropositive individuals, the only in vivo situation where full virus replication can be reliably observed is hairy leukoplakia (HL), a benign lesion of lingual epithelium frequently found in AIDS patients. Thus, the relative contribution of lymphoid cells and epithelial cells to latent EBV infection/persistence vs replication in vivo remains controversial. Recent studies suggest that HL represents a focus of EBV replication in the absence of a truly latent infection and this supports the contention that EBV persistence resides in the lymphoid compartment. These aspects together with the role of EBV in oral diseases and the effect of certain EBV genes on the control of epithelial cell growth and differentiation will be discussed.     

Design of the Dutch Obesity Intervention in Teenagers (NRG-DOiT): systematic development, implementation and evaluation of a school-based intervention aimed at the prevention of excessive weight gain in adolescents

Background

Immigrants to the U.S. are required to undergo overseas screening for tuberculosis (TB), but the value of evaluation and treatment following entry to the U.S. is not well understood. We determined the cost-effectiveness of domestic follow-up of immigrants identified as tuberculosis suspects through overseas screening.

Methods

Using a stochastic simulation for tuberculosis reactivation, transmission, and follow-up for a hypothetical cohort of 1000 individuals, we calculated the incremental cost-effectiveness of follow-up and evaluation interventions. We utilized published literature, California Reports of Verified Cases of Tuberculosis (RVCTs), demographic estimates from the California Department of Finance, Medicare reimbursement, and Medi-Cal reimbursement rates. Our target population was legal immigrants to the United States, our time horizon is twenty years, and our perspective was that of all domestic health-care payers. We examined the intervention to offer latent tuberculosis therapy to infected individuals, to increase the yield of domestic evaluation, and to increase the starting and completion rates of LTBI therapy with INH (isoniazid). Our outcome measures were the number of cases averted, the number of deaths averted, the incremental dollar cost (year 2004), and the number of quality-adjusted life-years saved.

Results

Domestic follow-up of B-notification patients, including LTBI treatment for latently infected individuals, is highly cost-effective, and at times, cost-saving. B-notification follow-up in California would reduce the number of new tuberculosis cases by about 6–26 per year (out of a total of approximately 3000). Sensitivity analysis revealed that domestic follow-up remains cost-effective when the hepatitis rates due to INH therapy are over fifteen times our best estimates, when at least 0.4 percent of patients have active disease and when hospitalization of cases detected through domestic follow-up is no less likely than hospitalization of passively detected cases.

Conclusion

While the current immigration screening program is unlikely to result in a large change in case rates, domestic follow-up of B-notification patients, including LTBI treatment, is highly cost-effective. If as many as three percent of screened individuals have active TB, and early detection reduces the rate of hospitalization, net savings may be expected.     

Laparoscopic cholecystectomy

In recent months, the technique of Laparoscopic Laser Cholecystectomy (LLC) was introduced at our institution. A small series is presented here involving 14 patients, seven of whom underwent LLC and seven in which a "mini-lap" cholecystectomy was performed. Symptomatic cholelithiasis was the indication for surgery in all cases, and operative cholangiograms were employed in 12 patients. Comparisons are made regarding length of hospitalization, recovery time and operative time. An improved recovery period is indeed demonstrated with LLC allowing return to normal activities and employment much sooner than with an open cholecystectomy. We suggest that, though some prudence and caution is advised, this appears to be a safe and feasible adjunct in the treatment of cholelithiasis.     

Canine hepacivirus is not associated with chronic liver disease in dogs

Canine hepacivirus (CHV) has recently been identified in liver and respiratory tract samples from dogs, and comparative phylogenetic analysis has confirmed it to be the closest genetic relative of hepatitis C virus (HCV) described to date. CHV offers great potential as a model system for HCV, but only if the underlying processes of infection and pathogenesis are similar for both viruses. However, it is not yet clear if CHV is hepatotrophic. Canine chronic hepatitis (CH) is a common and usually idiopathic disease that shares similar histological features to that of HCV infection of humans. To date, no study has attempted to determine whether CHV is involved in the aetiology of liver disease in dogs. We employed two nested PCR assays, using primers targeting regions of the helicase domain of CHV NS3, to identify viral nucleic acids in liver samples from 100 dogs with CH of unknown cause in the UK. We also used a sensitive luciferase immunoprecipitation system (LIPS) assay to screen serum samples from these dogs for the presence of anti‐CHV antibodies. Surprisingly, there was no evidence of exposure to, or a carrier state of, CHV in this large cohort, suggesting that the virus is not associated with CH in UK dogs. Future work, including transmission studies, is required to understand the pathogenesis of CHV in canids before it can be proposed as a surrogate model for HCV‐induced liver disease in man.     

Complications affecting preterm neonates from 1991 to 2006: what have we gained?

Aim: In this study, we determined whether outcome of preterm neonates has improved over a period of 16 years. Study design: Inborn neonates with a gestational age of 25.0–29.9 weeks were included. Patients with severe congenital malformations were excluded. Mortality and morbidity (chronic lung disease; CLD, intraventricular haemorrhage: IVH grade III or IV, cystic periventricular leukomalacia: cPVL, perforated necrotizing enterocolitis: NEC, severe retinopathy of prematurity needing surgery: ROP and cerebral palsy: CP) were compared in three periods (period 1: 1991–1996 n = 434; period 2: 1997–2001 n = 356; period 3: 2002–2006 n = 422). Results: Infant mortality decreased from 15.2% to 10.9%. CLD did not differ significantly between periods (14.1–14.8%). Perforated NEC decreased from 2.8% to 1.6%. IVH grade III and IV both remained at 5.7% in period 3, whereas cPVL decreased significantly from 4.5% to 1.6%. Cerebral palsy decreased from 5.8% to 3.5% in period 3. Two neonates in each period were in need of surgery for ROP. Conclusion: Inborn preterm patients showed an improved survival and a significant reduction in cPVL and CP. Perforated NEC showed a trend to decrease. CLD and IVH grade III and IV remain a matter of concern.