Repeated unilateral epidural blockade

Unilateral epidural analgesia occurring in a parturient three times in successive pregnancies is reported. Possible causes are reviewed, and clinical and radiological evidence in support of the most likely explanation are presented.     

N-acetyl-L-aspartate and other amino acid metabolites in Alzheimer's disease brain: a preliminary proton nuclear magnetic resonance study.

We used proton nuclear magnetic resonance spectroscopy in this preliminary study of perchloric acid extracts of 12 Alzheimer's disease (AD) and five control brain samples to measure the relative levels of taurine, aspartate, glutamine, glutamate, gamma-aminobutyric acid (GABA), and the putative neuronal marker, N-acetyl-L-aspartate (NAA). We found no significant changes in taurine, aspartate, or glutamine. NAA was lower in AD compared with control, and this decrease correlated with the number of senile plaques and neurofibrillary tangles in adjacent tissue sections. GABA levels also were lower in AD brain. Glutamate levels were greater in AD than control and showed a close, inverse correlation with NAA levels. These findings suggest that the decrease in NAA reflects neuronal loss and that remaining neurons could be exposed to a relative excess of glutamate and a relative lack of GABA. If present in the neurotransmitter pool, this imbalance could result in neurotoxic cell damage. This hypothesis is further supported by in vitro and in vivo phosphorus 31 nuclear magnetic resonance findings.     

PDGF AA as mediator in nicotine-dependent carcinogenesis

Effect of nicotine on PDGF AA and PDGF BB interaction with cervicalcancer SiHa cells was tested. [¹²⁵I]PDGF AA was internalizedby cells and accumulated in the cytoplasm and nucleus (chromatin).In the absence of nicotine, maximal accumulation of [¹²⁵I]PDGFAA inside the cells occurred after 1 day of incubation, whichwas followed by a progressive degradation of the growth factorduring the next 2, 3 and 5 days of cell exposure. In the presenceof 0.001 or 0.01% nicotine, accumulation of [¹²⁵I]PDGF AA wasslightly higher than in the absence of nicotine, and maximalaccumulation occurred after 2 days of incubation. In the presenceof 0.1% nicotine, maximal accumulation occurred after 5 daysof incubation and was 20 and 14 times higher in the cytoplasmand chromatin, respectively. Nicotine-postponed degradationand increased nuclear accumulation of PDGF AA resulted in activationof RNA synthesis and cell proliferation. PDGF BB, which wasnot internalized by cells did not respond to nicotine treatment.The proposed mechanism of nicotine-PDGF AA co-carcinogenesismay involve inhibition of growth factor degradation at the lysosomallevel and an increased chromatin accumulation of the non-degradedPDGF.     

Screening assays for immunologic infertility: a comparison study.

Because the immunobead antisperm antibody test (IBT) is difficult to learn and results are heavily operator-dependent, we compared findings on IBT with those of SpermMAR and SpermCheck in 58 patients to determine whether the latter two tests could demonstrate improved screening ability. Assays performed on both sperm and serum (i.e., direct and indirect) yielded 100% positive predictive values when IBT was used as the standard. Both SpermCheck and SpermMAR are easier to perform, and, as the former has a slightly greater sensitivity, we recommend SpermCheck for the detection of immunologic infertility.     

The effects of communication skills training on patients' participation during medical interviews

Recent models of physician-patient communication emphasize information exchange in promoting partnership. Although considerable attention has been given to physicians' information exchange, little research has examined patients' communication contributions. The purpose of this research was to test the effectiveness of a training booklet designed to enhance patients' communication skills in information exchange. A nested design was used, such that 25 physicians each saw six patients, two patients in each of three communication skills interventions (i.e. trained, informed, control). The dependent variables included several discourse categories designed to assess patients' information seeking, provision, and verifying. Results indicate that trained patients engaged in more effective and efficient information seeking, provided physicians with more detailed information about their medical condition, and used more summarizing utterances to verify information they received from physicians. Additionally, dyads consisting of trained patients demonstrated a more patient-controlled style of communication than did dyads consisting of informed or untrained patients.     

Localisation of aluminium by histochemical and electron probe x-ray microanalytical techniques in bone tissue of cases of renal osteodystrophy.

Histochemical studies and electron probe x-ray microanalysis for aluminium have been performed on 16 samples of undecalcified bone from cases of renal osteodystrophy associated with a syndrome suggestive of dialysis encephalopathy (five cases), age and sex matched controls for these and a group of patients with chronic renal failure (six cases) who have never been on haemodialysis. Aluminium was detected only in the patients with a dialysis encephalopathy-like syndrome. This group had significant histological bone disease the features of which were broadly consistent with the so-called atypical renal osteomalacia which is thought to be due to a metal toxin. Aluminium was demonstrated at the interface between osteoid and mineralised tissue--that is, at the site of the calcification front, where it could interfere with the mineralisation process. In the group of patients who had never been subjected to haemodialysis there was also significant histological bone disease but no evidence of aluminium accumulation. In this group the bone disease was of a more typical pattern of osteomalacic changes coupled with those of hyperparathyroidism.     

Studies using a viral challenge and CD8 T cell depletions on the roles of cellular and humoral immunity in the control of an SHIV-89.6P challenge in DNA/MVA-vaccinated macaques

Here, we study immune responses in four DNA/MVA-vaccinated macaques following an SHIV-89.6P challenge and a subsequent CD8 cell depletion. Both post-challenge and post-depletion peaks of viremia contracted with the expansion, or re-emergence, of CD8 T cells. Post-depletion, CD8 cells expanded in the presence of higher levels of neutralizing Ab and CD4 help than post-challenge and had superior maturational characteristics as measured by expression of the anti-apoptotic protein Bcl-2, the IL-7 receptor CD127 and co-production of IFN-gamma and IL-2. Pre-challenge and pre-depletion titers of neutralizing Ab correlated inversely with peaks of viremia and directly with peaks for anti-viral CD4 cells. Thus, our results reveal CD8 cells playing a central role, and neutralizing Ab, a supporting role in SHIV-89.6P control. They also suggest a dynamic relationship between neutralizing Ab, antigen load and anti-viral CD4 cells in the maturation of high-quality anti-viral CD8 T cells.