Resolution of infection status of human immunodeficiency virus (HIV)- seroindeterminate donors and high-risk seronegative individuals with polymerase chain reaction and virus culture: absence of persistent silent HIV type 1 infection in a high-prevalence area

To address concerns over the prevalence of silent (antibody-negative) infections among blood donors and high-risk populations, a combination of proviral amplification by polymerase chain reaction (PCR) and viral isolation by co-culture techniques was employed to resolve the human immunodeficiency virus type 1 (HIV-1) infection status of well-characterized groups of suspect blood donors and others identified in the blood bank setting. No silent infections were found in 65 follow-up samples from 26 persistently HIV-1-seroindeterminate blood donors, 16 persistently seronegative heterosexual partners of infected transfusion recipients, and 6 high-risk seronegative homosexual men identified through donor look-back investigations. In contrast, 21 seropositive controls tested positive. These results suggest a low prevalence of persistently silent infections in at-risk populations, even in high HIV prevalence regions. The PCR assay, with a co-detected internal positive control, and appropriate confirmatory algorithms, was found to be a useful direct assay to rule out infection, especially in concert with confirmatory virus isolation.     

Speech perception scores in cochlear implant recipients: An analysis of ceiling effects in the CUNY sentence test (Quiet) in post-lingually deafened cochlear implant recipients

Objectives: To evaluate the clinical utility of the City University of New York sentence test in a cohort of post-lingually deafened cochlear implants recipients over time.

Methods: 117 post-lingually deafened, Australian English-speaking CI recipients aged between 23 and 98 years (M?=?66 years; SD?=?15.09) were recruited. CUNY sentence test scores in quiet were collated and analysed at two cut-offs, 95% and 100%, as ceiling scores.

Results: CUNY sentence scores ranged from 4% to 100% (M?=?86.75; SD?=?20.65), with 38.8% of participants scoring 95% and 16.5% of participants reaching the 100% scores. The percentage of participants reaching the 95% and 100% ceiling scores increased over time (6 and 12 months post-implantation).

The distribution of all post-operative CUNY test scores skewed to the right with 82% of test scores reaching above 90%.

Discussion: This study demonstrates that the CUNY test cannot be used as a valid tool to measure the speech perception skills of post-lingually deafened CI recipients over time. This may be overcome by using adaptive test protocols or linguistically, cognitively or contextually demanding test materials.

Conclusion: The high percentage of CI recipients achieving ceiling scores for the CUNY sentence test in quiet at 3 months post-implantation, questions the validity of using CUNY in CI assessment test battery and limits its application for use in longitudinal studies evaluating CI outcomes. Further studies are required to examine different methods to overcome this problem.     

Microbiological culture analysis of the tongue anaerobic microflora in subjects with and without halitosis

Objective:  Determination of the microflora present on the tongue dorsum of subjects with and without halitosis using conventional microbiological culture methods.
Methods:  Twenty-one halitosis and 20 control patients were recruited using a strict clinical protocol. Samples were collected from the posterior dorsum of the tongue using a sterile brush. Each sample was vortex mixed for 30 s and serial 10-fold dilutions to 10⁻⁷ were carried out. Samples were plated onto fastidious anaerobe agar (FAA) and FAA enriched with vancomycin. These were incubated under anaerobic conditions for 10 days at 37°C. Strict anaerobes were identified by metronidazole sensitivity and bacteria were identified to genus level by a combination of colony morphology, Gram staining and biochemical and enzymatic tests (rapid ID 32 A).
Results:  The predominant species in test and control groups were Veillonella sp. and Prevotella sp. Greater species diversity was found in the halitosis samples compared with controls. The halitosis samples contained an increased incidence of unidentifiable Gram-negative rods, Gram-positive rods and Gram-negative coccobacilli.
Conclusions:  There was no obvious association between halitosis and any specific bacterial genus. The increased species diversity found in halitosis samples suggests that halitosis may be the result of complex interactions between several bacterial species. The role of uncultivable bacteria may also be important in contributing to this process.     

Long-term Physiologically Regulated Expression of the Low-density Lipoprotein Receptor In Vivo Using Genomic DNA Mini-gene Constructs

Familial hypercholesterolemia (FH) is a condition caused by mutations in the low-density lipoprotein receptor (LDLR) gene. Expression of LDLR is highly regulated and excess receptor expression is cytotoxic. To incorporate essential gene regulation into a gene therapy vector for FH, we generated vectors in which the expression of therapeutic human LDLR gene, or luciferase reporter gene, is driven by 10 kb of human LDLR genomic DNA encompassing the promoter region including elements essential for physiologically regulated expression. Using luciferase expression and specific LDL binding and internalization assays, we have shown in vitro that the genomic promoter element confers long-term, physiologically regulated gene expression and complementation of receptor deficiency in culture for 240 cell-generations. This was demonstrated in the presence of sterols or statins, modifiers of LDLR promoter activity. In vivo, we demonstrate efficient liver-specific delivery and expression of luciferase following hydrodynamic tail-vein injection and confirm that expression from the LDLR promoter element is sensitive to statin administration. We also demonstrate long-term LDLR expression from the 10-kb promoter element up to 9 months following delivery. The vector system that we describe provides the efficient delivery, long-term expression, and physiological regulation required for a successful gene therapy intervention for FH.     

A randomized controlled trial testing the effectiveness of a universal school-based depression prevention program 'Op Volle Kracht' in the Netherlands

Background  

The incidence of depressive symptoms increases during adolescence, from 10.0% to 24.5% at age 11 to 15, respectively. Experiencing elevated levels of depressive symptoms increases the risk of a depressive disorder in adulthood. A universal school-based depression prevention program Op Volle Kracht (OVK) was developed, based on the Penn Resiliency Program, aimed at preventing the increase of depressive symptoms during adolescence and enhancing positive development. In this study the effectiveness of OVK will be tested and possible mediators of program effects will be focus of study as well.