HIV-Related Stigma and Psychological Adjustment Among Perinatally HIV-Infected Youth in Cape Town,South Africa

AIDS and Behavior - The effect of chronic HIV-infection on psychological adjustment, including the impact of HIV-related stigma in perinatally HIV-infected (PHIV+) youth across Africa is largely...     

Dimensions of osteoarthritis self-management

Our aims were to determine whether a taxonomy of self-management strategies for osteoarthritis could be identified, and whether the resultant dimensions of such a taxonomy demonstrate predictable relationships with health status indices. Participants (n = 117) from community-based self-help groups and a general rheumatology outpatient clinic completed a self-management inventory consisting of 11 items, answered for both the past 7 days and a day on which symptoms were worse than usual. Duration of symptoms, level of pain, perceived functional ability and self-rated health were recorded as indicators of health status. Three essentially identical factors were obtained for both past 7 days and worse day items. Resultant scales were labeled passive, complementary and active, respectively. Correlations with health status measures provided modest evidence for the construct validity of these self-management scales. Compared with a simple aggregate score based on the total number of strategies used, the scales provided a clearer understanding of the relationship between self-management and health. The study provided a useful extension to existing research, addressing a number of shortcomings identified by previous researchers. The identified self-management dimensions offered a greater insight into the self-management choices of patients. Suggestions for further improvements to the measurement of self-management are outlined.Abbreviations OA Osteoarthritis     

Predominant or complete recipient T-cell chimerism following alemtuzumab-based allogeneic transplantation is reversed by donor lymphocytes and not associated with graft failure

The clinical significance of mixed chimerism following allogeneic haematopoietic stem cell transplantation (HSCT) remains controversial. Its relevance and incidence are probably influenced by the conditioning regimen and incorporation of T‐cell depletion. The presence of recipient chimerism levels >40–50% following T‐cell replete reduced intensity transplantation correlates with a high risk of graft rejection, regardless of donor‐lymphocyte infusions, but it is unclear whether this finding translates to T‐cell depleted transplants. We conducted a retrospective single‐institution analysis of patients receiving alemtuzumab‐based HSCT. 27/152 (18%) evaluable cases had predominantly recipient T‐cell chimerism at 3 months or beyond. By contrast, coincident chimerism in the granulocyte lineage was predominantly of donor origin (median 100%) in all but one patient. Donor lymphocyte infusion effectively converted predominantly recipient T‐cell chimerism to ful donor chimerism in all evaluable cases including three cases with no detectable donor T cells. The only graft failure occurred in the patient with predominantly recipient myeloid chimerism in whom rejection occurred rapidly before donor lymphocytes could be administered. We conclude that predominant or complete recipient T‐cell chimerism following alemtuzumab‐based regimens does not have the same clinical implications as that following T‐cell replete transplants and can be effectively converted with donor lymphocytes without the need for lympho‐depleting agents or re‐conditioning.     

The effects of verbalisation on cognitive performance in schizophrenia: A pilot study using tasks from the Delis Kaplan Executive Function System

Cognitive impairment is common in schizophrenia, and has adverse effects on functional outcome. Cognitive remediation strategies in which people with schizophrenia speak aloud (verbalise) during task performance have demonstrated some success in improving performance on the Wisconsin Card Sorting Test. This study extends previous research by assessing whether verbalisation also improves performance on tasks selected from the Delis-Kaplan Executive Function System (D-KEFS).

Twenty two subjects with schizophrenia participated in the study. We used a within subjects design to compare performance on the D-KEFS Tower Test and Trail Making Test when participants (a) produced concurrent verbalisation, or (b) remained silent.

Results demonstrated selective benefits of verbalisation on a neuropsychological task requiring multiple executive functions (number-letter switching task), while performance on tasks requiring simpler single-component cognitive functions (visual scanning and motor speed tasks) was adversely affected.

The effects of verbalisation on the cognitive task performance of patients with schizophrenia differ depending on the nature of the task. Benefits are seen in tests of executive skills but performance worsens in single component cognitive tasks. When developing cognitive remediation strategies for people with schizophrenia, consideration should be given to the nature and cognitive demands of each task before recommending verbalisation strategies.     

Etomidate reduces initiation of backpropagating dendritic action potentials: implications for sensory processing and synaptic plasticity during anesthesia

Anesthetics may induce specific changes that alter the balance of activity within neural networks. Here we describe the effects of the GABA(A) receptor potentiating anesthetic etomidate on sensory processing, studied in a cerebellum-like structure, the electrosensory lateral line lobe (ELL) of mormyrid fish, in vitro. Previous studies have shown that the ELL integrates sensory input and removes predictable features by comparing reafferent sensory signals with a descending electromotor command-driven corollary signal that arrives in part through parallel fiber synapses with the apical dendrites of GABAergic interneurons. These synapses show spike timing-dependent depression when presynaptic activation is associated with postsynaptic backpropagating dendritic action potentials. Under etomidate, almost all neurons become tonically hyperpolarized. The threshold for action potential initiation increased for both synaptic activation and direct intracellular depolarization. Synaptically evoked inhibitory postsynaptic potentials (IPSPs) were also strongly potentiated and prolonged. Current source density analysis showed that backpropagation of action potentials through the apical dendritic arborization in the molecular layer was reduced but could be restored by increasing stimulus strength. These effects of etomidate were blocked by bicuculline or picrotoxin. It is concluded that etomidate affects both tonic and phasic inhibitory conductances at GABA(A) receptors and that increased shunting inhibition at the level of the proximal dendrites also contributes to increasing the threshold for action potential backpropagation. When stimulus strength is sufficient to evoke backpropagation, repetitive association of synaptic excitation with postsynaptic action potential initiation still results in synaptic depression, showing that etomidate does not interfere with the molecular mechanism underlying plastic modulation.