Development and psychometric validation of the HIV Treatment Knowledge Scale.

Accurate treatment knowledge is required for patients to successfully manage complex medical conditions. Existing HIV knowledge scales focus on disease transmission and risk factors. This is the first study to develop and validate a scale to measure HIV treatment knowledge about complex treatment issues such as adherence, side-effects and drug resistance. A total of 346 participants were recruited into this cross-sectional study. Participants included HIV-positive patients (n=130), HIV-hepatitis C co-infected patients (n=22), hepatitis C patients, (n=78), community healthcare providers (n=35) and college students (n=81). Participants completed the proposed HIV Treatment Knowledge Scale and a validated measure of general knowledge about HIV transmission and risk factors. Two-week test-retest data were collected. Results demonstrated that the HIV Treatment Knowledge Scale was significantly correlated with general HIV knowledge across all samples. Among HIV-positive patients, the HIV Treatment Knowledge Scale was positively associated with time since HIV diagnosis. HAART-experienced patients had significantly higher treatment knowledge than HAART-naïve patients. HIV-positive patients scored significantly higher than hepatitis C patients and college students on HIV treatment knowledge. Test-retest reliability (r=0.83) and internal consistency (reliability coefficient=0.90) were both satisfactory. The HIV Treatment Knowledge Scale is a novel, easy-to-administer measure demonstrating high levels of validity and reliability. It has important applications as a clinical teaching tool with patients and healthcare workers and it could be used as an outcome indicator in HIV educational intervention studies.

A randomized controlled psycho-education intervention trial: Improving psychological readiness for successful HIV medication adherence and reducing depression before initiating HAART.

The purpose of this study was to evaluate a novel psycho-educational intervention intended to increase patients' medication preparedness and treatment adherence skills before initiating highly active antiretroviral therapy (HAART). Sixty-three HIV-positive patients not currently on antiretroviral therapy participated in a randomized controlled trial of a standardized, four-session psycho-educational intervention (Supportive Therapy for Adherence to Antiretroviral Treatment; STAART). Session topics included learning techniques to increase medication adherence and learning effective strategies to cope with stress and depression. Patients completed psychological questionnaires assessing psychological readiness to initiate HAART and depressed mood. They completed both measures at study baseline and at four-weeks post-baseline. After controlling for baseline medication readiness scores, intervention patients (n = 30) reported significantly higher mean medication readiness following the STAART intervention (four-weeks post-baseline) (27.3+/-6.9) compared to controls (n = 33; 24.6+/-9.9; p < 0.05). Among depressed patients (n = 27), those receiving the intervention (n = 15) reported significantly lower mean depression scores at four-weeks post-baseline (22.5+/-12.9) compared to controls (n = 12; 27+/-9.9; p < 0.05). The STAART intervention enhanced HIV treatment readiness by better preparing patients prior to initiating HAART. It was also beneficial for reducing depressive symptoms in depressed, HIV-positive patients.

Interleukin-7 receptor expression on CD8(+) T cells is reduced in HIV infection and partially restored with effective antiretroviral therapy.

Interleukin (IL)-7 enhances CD8 T-cell proliferation and cytolytic activity. The expression of its receptor, CD127 (IL-7R alpha), may therefore be important in the immunopathogenesis of HIV disease. CD127 expression on CD8(+) T cells from HIV seronegative controls, untreated HIV-seropositive patients, and HIV-positive patients receiving antiretroviral therapy with sustained viral suppression was analyzed by flow cytometry in a cross-sectional study. Among healthy controls, 65% of CD8 cells expressed CD127 ( n = 7). This dropped to 21.6% among untreated HIV-positive patients ( n = 16), and approached normal levels (47.7%) in HIV-positive individuals on effective therapy ( n = 20). The same pattern was observed for naïve (CD45RA(+) ) and memory (CD45RO(+) ) CD8(+) T cells but changes were more extreme within the memory cell population. Duration of viral suppression was the only parameter evaluated that correlated with extent of CD127 expression in treated patients. Impairment of CTL activity in HIV disease may be caused, in part, by downregulation of IL-7 receptor expression. Improved immune function with effective antiretroviral therapy is associated with recovery of this molecule. The correlation between virologic suppression and apparent CD127 recovery suggests that essential cytokine signaling pathways may be restored with sustained inhibition of viral replication.

A rapid procedure for initial drug evaluation.

The overall aim of this work is to develop computer simulations to aid in the selection of proposed medicines and identify those most likely to succeed. One important feature is a systems approach to simulate both the target area with which the drug is designed to interact as well as the surrounding areas where feedback mechanisms may alter the expected effect. The simulation must be rapid if it is to be used to evaluate large numbers of potential drugs. Thus the procedure simplifies many of the known complex phenomena to provide a general framework and feedback mechanisms. An example of the use of the simulation to study a drug used to treat hypertension is given. A possible use of the technique is shown using the example of the effect of varying the drug dosage on the contraction of the arteriole muscle.

P19 cells differentiate into glutamatergic and glutamate-responsive neurons in vitro.

The neurotransmitter L-glutamate has been associated with a number of developmental events within the central nervous system including synaptogenesis and the refinement of topographically ordered neural maps. As a model for studying such events at the molecular level, we have examined the expression of glutamate and glutamate receptors in neurons that develop from P19 cells in response to retinoids. We report here that many P19-derived neurons do contain glutamate in secretory vesicles and that this glutamate appears to function as a neurotransmitter. The neurotransmitter GABA is also present in these cultures and both glutamate and GABA appeared to co-localize in some neuronal processes. Both neurotransmitters were released from the neurons in response to membrane depolarization. These neurons also express various glutamate receptor subunits including GluR1, GluR4 and NMDAR1 as detected by immunological methods. Using whole-cell patch-clamping, we have recorded spontaneous postsynaptic potentials which increase in both amplitude and frequency with time in culture and which are sensitive to the glutamate antagonist kynurenic acid Thus, P19-derived neurons mature in culture and form electrically active neural networks involving glutamate and glutamate receptors.