Death of sensory ganglion neurons after acute withdrawal of nerve growth factor in dissociated cell cultures

The time course of dependence on nerve growth factor (NGF) for survival in sensory neurons in vitro was examined with microscopic and biochemical methods. Primary dorsal root ganglion (DRG) cultures from embryonic-day-15 (E-15) and day-19 (E-19) rats were maintained with standard dissociated cell culture techniques in the absence of most non-neuronal cells. After various times in culture, neurons were acutely deprived of neurotrophic support by changing to NGF-free medium and adding NGF antiserum to eliminate any residual NGF. Neuronal cultures were examined with phase microscopy; and, their metabolic activity was measured with a protein assay at various time points after NGF deprivation. E-15 neurons grown in culture for 5 days were exquisitely sensitive to acute NGF deprivation. By 12 h after NGF deprivation, neuronal morphology was severely disrupted and the majority of neurons appeared dead. E-15 neurons grown in culture for 8 or 11 days showed progressively less dependence on NGF for survival. These older neurons did not die until 24 and 48 h, respectively, following NGF withdrawal. Neurons grown in culture for 20 days did not show any morphologic changes by phase microscopy up to 4 days after NGF deprivation. Protein incorporation progressively decreased between 12 and 48 h after NGF withdrawal in E-15 neurons grown in culture for 5, 8, or 11 days.(ABSTRACT TRUNCATED AT 250 WORDS)     

Expression of c-erbB-2 protein in keratinocytes of oral mucosal lichen planus and subsequent squamous cell carcinoma

Oral mucosal lichen planus (OMLP) is a well recognized mucosal disease with unknown etiology. Considerable controversy exists as to whether OMLP is intrinsically premalignant, or if the disorder facilitates the development of oral mucosal squamous cell carcinoma (OMSCC) by external factors. The aim of the present study was to investigate the expression of c-erbB-2 protein in the keratinocytes of initial biopsies of oral mucosal disorders diagnosed as OMLP with no evidence of epithelial dysplasia. and to compare the results with the expression of c-erbB-2 protein in subsequent biopsies obtained from the same patients. These results were compared with the findings from control groups (patients with dysplasia with no evidence of OMLP, patients with OMSCC with no evidence of OMLP and normal oral mucosa). The expression of the c-erbB-2 protein was evaluated by immunohistochemical staining of the gene product with the avidin-biotin-complex method using paraffin-embedded tissue sections. Five of the initial biopsies from patients with OMLP expressed the c-erhB-2 protein and one did not. None of the OMLP cases that subsequently showed evidence of dysplasia expressed the c-erhB-2 protein, and of the three OMSCC specimens from the patients with OMLP. two were negative and one expressed c-erbB-2 protein. The specimens from the control groups all expressed the c-erhB-2 protein. The results indicated the probability of the absence of c-erbB-2 staining being an indication of a potential for neoplastic transformation in OMLP with dysplastic changes.     

Familial clustering of insulin sensitivity.

This study's objective was to determine whether there is familial clustering of insulin sensitivity (SI) or insulin-independent glucose uptake (SG), which would be evidence that they are genetically determined traits. Outpatients had a 3-h intravenous glucose tolerance test. Nondiabetic individuals (n = 183), ranging in age from 16 to 60 yr, were from 105 families that had 2 parents with non-insulin-dependent diabetes mellitus. Of these families, 62 contributed 1 offspring, 21 contributed 2, 13 contributed 3, 6 contributed 4, and 2 and 1 contributed 5 and 6, respectively. The minimal model of glucose disposal and the glucose and insulin values from the intravenous glucose tolerance tests were used to estimate SI and SG. The intraclass correlation coefficient was used to compare the within-family variability of SI and SG with the respective between-family distributions. The intraclass correlation coefficients were 0.26 (P = 0.008) for SI and 0.081 (P = 0.45) for SG. SI and SG were uncorrelated (r = -0.059, P = 0.42). The intraclass correlation of SI could not be explained by familial clustering of fasting insulin or ideal body weight. Finally, the 10 families with the lowest values of SI had a significantly higher within-sibship variability of SI than the other 33 families (P less than 0.001, F test). SI but not SG showed familial clustering, which is consistent with a polygenic determinant of SI. In addition, a large within-family variability of SI in some families is compatible with a major gene effect with a dominant mode of inheritance.(ABSTRACT TRUNCATED AT 250 WORDS)     

A longitudinal study of mental health consumer/survivor initiatives: Part 3—A qualitative study of impacts of participation on new members

This article examines the outcomes of participation in mental health Consumer/Survivor Initiatives (CSIs) and identifies helpful qualities of CSIs through a longitudinal, qualitative study that involved in‐depth interviews of people who experienced severe mental health challenges in Ontario, Canada. We used a nonequivalent control group design in which we compared active participants in CSIs ( n = 15) with nonactive participants ( n = 12) at baseline and at 9‐ and 18‐month follow‐up intervals. Compared with non‐CSI participants, CSI participants reported more stable mental health, enhanced social support, sustained work, stable income, and participation in education and training at 9‐ and 18‐month interviews. The helpful qualities of CSIs that participants reported were (1) safe environments that provide a positive, welcoming place to go; (2) social arenas that provide opportunities to meet and talk with peers; (3) an alternative worldview that provides opportunities for members to participate and contribute; and (4) effective facilitators of community integration that provide opportunities to connect members to the community at large. The findings are discussed in terms of previous research in self‐help and consumer‐run organizations in mental health. © 2006 Wiley Periodicals, Inc.     

Isoflurane Pretreatment Has Immediate and Delayed Protective Effects against Cytokine-induced Injury in Endothelial and Vascular Smooth Muscle Cells

Background: Volatile anesthetics have protective effects against cytokine-induced injury in endothelial and vascular smooth muscle cells. The authors hypothesized that isoflurane pretreatment may trigger immediate and delayed protection that is modulated by adenosine triphosphate-sensitive potassium channels.

Methods: Human and bovine endothelial cells and rat vascular smooth muscle cells were pretreated with isoflurane (1.5% for 30 min) and then exposed to cytokines (tumor necrosis factor-[alpha], interferon-[gamma], and interleukin-[beta]) for 72 h. Cytokine exposure was initiated immediately after isoflurane pretreatment or after a delay of 1-48 h. Cell survival and viability were evaluated by trypan blue exclusion and lactate dehydrogenase release. The role of mitochondrial and cell membrane adenosine triphosphate-sensitive potassium channels, or both, were evaluated with the antagonists 5-hydroxydecanoate, HMR-1098, or glybenclamide.

Results: Immediate isoflurane pretreatment was approximately 70% effective in increasing cell survival and prevented lactate dehydrogenase release in all cell lines. However, cellular protection was completely lost if the time between isoflurane and cytokine exposure was extended to 2-12 h, depending on the cell type. Delayed protection was equal to immediate protection when the interval was extended to 12-24 h, with protection being sustained at 48 h in human endothelial and rat vascular smooth muscle cells. The immediate and delayed protection was inhibited by glybenclamide and 5-hydroxydecanoate but not by HMR-1098, whereas diazoxide, a mitochondrial adenosine triphosphate-sensitive potassium channels agonist, mimicked the time course of isoflurane-induced immediate and delayed protection in all cell lines.     

Ten-year trends in neonatal assisted ventilation of very low-birthweight infants.

OBJECTIVES: To examine ventilatory support for the VLBW infant over the past 10 years in a single academic NICU and determine factors that predicted length of ventilation, death, and CLD. STUDY DESIGN: A retrospective cohort review of neonatal blood gases, ventilatory support, and clinical outcomes. RESULTS: From 1992 through October 2002, 6254 infants were admitted, of whom 2388 required intubation for mechanical ventilation. Of these, 837 were <1500 g at birth (VLBW) infants and 453 were less than 1000 g (ELBW). Total duration of ventilation decreased in all weight groups. Noninvasive ventilatory support increased from 20 to 55% of total ventilation from 1997 to 2002. During this same period, CLD decreased from 20 to 11% in ventilated VLBW infants. Duration of total ventilation was best predicted by birth weight, with each 100 g increment decreasing the duration of ventilation by 71 hours. Lower birth weight, male sex, and a longer total duration of ventilatory support were significant factors in predicting the occurrence of CLD. Death alone was best predicted by lower birth weight and maximum oxygen index (OI). Transported infants had significantly increased maximal OIs, durations of ventilation, and incidence of death. A total of 48% of infants with a single OI >10 either died or survived with CLD. CONCLUSIONS: Birth weight is the best predictor of duration of ventilation, and CLD is best predicted by birth weight, duration of ventilation and male sex. The increasing use of noninvasive strategies has not been associated with an observable increase in respiratory morbidity. VLBW infants with a single OI>10 may benefit from inclusion in future interventional rescue studies.     

Treatment of chronic mucocutaneous moniliasis by immunologic reconstitution

The immunological defect in a patient with chronic mucocutaneous moniliasis was characterized. While his Candida skin test was negative. exposure of his lymphocytes to candida extracts in vitro produced an increase in thymidine incorporation. Supernatants from cultures of antigen-stimulated lymphocytes did not contain macrophage migration-inhibition factor (MIF) activity.

Restoration of the immune system with transfusions of immuno-competent allogeneic lymphocytes was accompanied by conversion of the Candida skin test to positive, and MIF production by his lymphocytes. During the period that his immune system remained intact, there was marked clearing of the moniliasis. Eight months following the transfusions, the moniliasis recurred and when restudied, the patient again had negative skin tests and insignificant MIF production.

These observations demonstrate the importance of mediators in the expression of delayed hypersensitivity and provide evidence of a role of cellular immunity in resistance to certain chronic fungal infections.