Symptomatology of late-life minor depression among primary care patients

Patients of four general internists and four family physicians were interviewed by two psychiatrists to identify those suffering from depressive disorders. Nineteen elderly (60 years of age and older) patients and 22 younger (between 18 and 59 years of age) patients met Research Diagnostic Criteria (RDC) for minor depressive disorder, and 73 elderly and 79 younger patients had no psychiatric disorder. In general, the elderly depressed medical outpatients and the younger depressed medical outpatients had similar symptomatology, as did the elderly and nonelderly medical outpatients without psychiatric disorders.     

Evaluation of the Spot-CAMP test for the rapid presumptive identification of group B streptococci

A rapid Spot-CAMP test was evaluated for its ability to accurately identify colonies of Streptococcus agalactiae (Lancefield Group B) growing on primary sheep blood agar plates. The test uses a beta-lysin-containing filtrate, which is prepared from a broth culture of Staphylococcus aureus. A drop of beta-lysin filtrate is applied adjacent to a suspected group B Streptococcus (GBS) colony and the plate is incubated and then examined for a zone of synergistic hemolysis. The Spot-CAMP test demonstrated 100% correlation with both a Standard CAMP procedure and Lancefield serogrouping. The rapid Spot-CAMP test was easy to perform and inexpensive, and could presumptively identify within 30 minutes colonies of GBS growing on primary isolation plates.     

Cardiovascular patterns associated with threat and challenge appraisals: a within-subjects analysis

Previous studies demonstrated distinct cardiovascular patterns associated with threat and challenge appraisals for groups of participants. We extend these results by assessing whether appraisals continue to be associated with these cardiovascular response patterns within an individual as appraisals change. Participants completed four verbal mental arithmetic tasks for which they made appraisals before and after each task. Cardiac reactivity and total peripheral resistance (TPR) were calculated for the first and last minutes of each task, and the number of responses and percent correct were measured for each task. In line with our prediction, pretask appraisals were related to some task-related cardiac responses across the four tasks. In addition, task-related cardiovascular reactivity and behaviors both influenced appraisals following the task. Our findings suggest that an idiographic analysis of appraisals, cardiovascular physiology, and task-related behaviors provides a richer understanding of the appraisal process and reveals sex differences deserving further assessment.     

The protective effects of hyperimmune anti-murine cytomegalovirus antiserum against lethal viral challenge: the case for passive-active immunization

The administration of 0.2 ml of hyperimmune anti-mouse cytomegalovirus (CMV) antiserum intraperitoneally (ip) or intravenously provided complete protection against lethal challenge (10(5.8) PFU ip) with murine CMV. Antiserum protection was complete when the antiserum was administered as long as 24 hr after viral challenge. The administration of antiserum had little effect on the titers of virus in the organs of these animals. Ammonium sulfate-treated antiserum provided similar complete protection. Animals rechallenged with 10(6)-10(6.5) PFU of murine CMV 1 month after initial challenge, at a time when the administrated antiserum was no longer detectable, all survived. We conclude that hyperimmune antiserum can provide significant protection against otherwise lethal murine CMV infection, that the protecting material lies within the immunoglobulin fraction, and that long-term immunity results from the combined exposure to virus and antiserum. Such passive-active protection could be useful in protecting against human CMV infection.     

Experimental interstitial renal fibrosis in rats: nephritis induced by N-(3,5-dichlorophenyl)succinimide.

The nephrotoxic properties of the chemical N-(3,5-dichlorophenyl)-succinimide were investigated in rats with a view to establishing the usefulness of this chemically-induced nephritis as a model of chronic interstitial renal fibrosis. The compound was synthesized and given daily by gastric intubation as a suspension in arachis oil B.P. to male WAG-strain rats, for periods of up to 108 days. Polydipsia and polyuria resulted rapidly in all treated animals and persisted for the duration of the experiment. There was a progressive increase in the extent of proteinuria in all treated animals and, by the end of the experiment, there was an increase in the plasma levels of urea and creatinine. Short term treatment (up to 3 days) resulted in focal areas of necrosis of some proximal convoluted tubules. Treatment for 28 days resulted in patchy but severe tubular interstitial nephritis with which was associated a moderate interstitial fibrosis. By 108 days, the nephritis was more widespread and the interstitial fibrosis was severe. The activity of proline hydroxylase, a part of the intracellular sequence of collagen synthesis, showed progressive increase in the renal cortex throughout the experiment and there was an associated increase in the cortical hydroxyproline content, a measure of the amount of collagen present. Associated with this biochemical evidence of an active, chronic fibrosis, was an increased water content of the cortical tissue. The results indicate that this chemically-induced, tubular interstitial nephritis is indeed a good and reliable model of interstitial renal fibrosis.     

Co-expression of the P75 neurotrophin receptor and neurotrophin receptor-interacting melanoma antigen homolog in the mature rat brain

The p75 neurotrophin receptor (p75(NTR)) is involved in the regulation of neuronal survival and phenotype, but its signal transduction mechanisms are poorly understood. Recent evidence has implicated the cytoplasmic protein NRAGE (neurotrophin receptor-interacting MAGE (from Melanoma AntiGEn) homolog) in p75(NTR) signaling. To gain further insight into the role of NRAGE, we investigated the co-expression of NRAGE and p75(NTR) in mature rat brain. In all areas examined, NRAGE appeared to be confined to neurons. In the basal forebrain cholinergic complex, NRAGE immunoreactivity was evident in all p75(NTR)-positive neurons. There were many more NRAGE-positive than p75(NTR)-positive neurons in these regions, however. NRAGE was also expressed in areas of the basal forebrain that did not express p75(NTR), including the lateral septal nucleus and the nucleus accumbens. A finding in marked contrast to previous studies was the presence of p75(NTR) immunoreactivity in neuronal cell bodies in the hippocampus. Hippocampal p75(NTR) immunoreactivity was apparent in rats 6 months and older, and was localized to the dentate gyrus and stratum oriens. All p75(NTR)-positive neurons in the dentate gyrus and hippocampal formation were positive for NRAGE. The majority of granular cells of the dentate gyrus and pyramidal cells in the hippocampal formation were positive for NRAGE and negative for p75(NTR). NRAGE was also present in some neuronal populations that express p75(NTR) after injury, including striatal cholinergic interneurons, and motor neurons. A region of marked disparity was the cerebral cortex, in which NRAGE immunoreactivity was widespread whereas p75(NTR) was absent. The results are consistent with an important role for NRAGE in p75(NTR) signaling, as all cells that expressed p75(NTR) also expressed NRAGE. The wider distribution of NRAGE expression suggests that NRAGE may also participate in other signaling processes.