Proteolipid protein gene expression in demyelination and remyelination of the central nervous system: a model for multiple sclerosis.

We asked whether nonlethal injury to the oligodendrocyte as manifested by altered myelin gene expression is an early event in the pathogenesis of demyelinating disease and subsequent remyelination. Using simultaneous in situ hybridization and immunocytochemistry, we studied expression of proteolipid protein (PLP) antigen and mRNA in spinal cords of normal adult mice and of mice infected with Theiler's virus which provides an excellent model for multiple sclerosis. Downregulation of PLP mRNA was observed within 3 days and persisted for as long as 367 days following intracerebral virus infection of SJL/J mice which are susceptible to chronic demyelination. Downregulation of myelin gene products preceded the development of prominent inflammation and demyelination observed following virus infection. In contrast, no change from control uninfected mice was observed in the expression of PLP mRNA following infection of C57BL/10SNJ mice which are resistant to demyelination. Treatment of chronically infected susceptible SJL/J mice with a regimen which promotes CNS-type (oligodendroglial) remyelination resulted in a 3- to 4-fold increase in PLP mRNA expression in oligodendrocytes. Actin mRNA expression in PLP antigen-positive cells was unchanged following TMEV-induced demyelination or remyelination indicating up- or downregulation of myelin gene products as compared to constitutively expressed actin gene. These experiments support the hypothesis that early regulation of myelin gene expression may be an important determinant in demyelination and in remyelination following nonlethal injury to oligodendrocytes.

R-cadherin expression in the developing and adult zebrafish visual system.

Cell adhesion molecules in the cadherin family have been implicated in histogenesis and maintenance of cellular structure and function in several organs. Zebrafish have emerged as an important new developmental model, but only three zebrafish cadherin molecules have been identified to date (N-cadherin, paraxial protocadherin, and VN-cadherin). We began a systematic study to identify other zebrafish cadherins by screening zebrafish cDNA libraries using an antibody raised to the cytoplasmic domain of mouse E-cadherin. Here, we report a partial cDNA with extensive sequence homology to R-cadherin. Spatial and temporal expression of this putative zebrafish R-cadherin was examined in embryos and adults by Northern analysis, RNase protection, and in situ hybridization. R-cadherin message increased during embryogenesis up to 80 hours postfertilization (hpf) and persisted in adults. In the embryonic brain, R-cadherin was first expressed in groups of cells in the diencephalon and pretectum. In adult zebrafish brain, R-cadherin continued to be expressed in several specific regions including primary visual targets. In the retina, R-cadherin was first detected at about 33 hours postfertilization in the retinal ganglion cell layer and the inner part of the inner nuclear layer. Expression levels were highest during periods of axon outgrowth and synaptogenesis. Retrograde labeling of the optic nerve with 1,1'-dioctadecyl-3,3,3',3', tetramethylindocarbocyanine perchlorate (DiI) followed by in situ hybridization confirmed that a subset of retinal ganglion cells in the embryo expressed R-cadherin message. In the adult, R-cadherin expression continued in a subpopulation of retinal ganglion cells. These results suggest that R-cadherin-mediated adhesion plays a role in development and maintenance of neuronal connections in zebrafish visual system.

Etiology, diagnosis, and treatment of nonepileptic seizures.

Psychogenic nonepileptic seizures (NES) can be classified into five categories. This review focuses on NES associated with emotional conflict, by far the most common and important group. Etiology is speculative, but the background histories of these patients are often similar. The presence of a trauma history, depression, post-traumatic stress symptoms, and the use of dissociation plus cognitive dysfunction possibly point to an organic etiology. The presentation of NES in children and adults is discussed, along with the differential diagnosis. The diagnostic differential is lengthy, with epileptic seizures of frontal lobe origin presenting a unique challenge. Diagnostic procedures are reviewed with an emphasis on the utility of hypnosis with seizure induction. Presenting the diagnosis to the patient, the role of the neurologist, and the role of the mental health consultant are reviewed. Issues in the doctor-patient relationship are also addressed, as well as the overall prognosis.

Effects of atropine and methacholine on deposition and clearance of inhaled particles in the donkey.

The influence of sympathetic and parasympathetic controls on regional particle deposition and mucociliary clearance rates was studied in the donkey in vivo. The deposition and clearance characteristics for gamma-tagged monodisperse ferric oxide microspheres were determined for inhalation tests after atropine and methacholine injections and were compared with the characteristics determined for control tests with the same animals and aerosols. Additional tests were performed in which methacholine was injected immediately after the test aerosol inhalation and 2 1/2 h before the particle inhalation. Particle deposition is shifted distally by atropine. Methacholine produces a proximal shift initially and a distal shift 2 1/2 h later. Atropine slows mucociliary transport. Methacholine produces an acceleration in bronchial clearance initially but causes a reduced rate of clearance 2 1/2 h later. Atropine slows mucociliary transport. Methacholine produces an acceleration in bronchial clearance initially but causes a reduced rate of clearance 2 1/2 h later. It also produces an initial surge in tracheal transport, which frequently leads to tracheal mucus refluxing and thereby an increase in average tracheal residence time. The drugs were used to modify the normal deposition and clearance characteristics of a particular animal so that they resembled the normal characteristics of a different animal, suggesting that much of the large intersubject variability may be attributable to different levels of autonomic tone.

Detection of intraoperative incidents by electronic scanning of computerized anesthesia records. Comparison with voluntary reporting.

BACKGROUND: The use of a computerized anesthesia information management system provides an opportunity to scan case records electronically for deviations from specific limits for physiologic variables. Anesthesia department policy may define such deviations as intraoperative incidents and may require anesthesiologists to report their occurrence. The actual incidence of such events is not known. Neither is the level of compliance with voluntary reporting. METHODS: Using automated anesthesia record-keeping with long-term storage, physiologic data were recorded every 15 s from 5,454 patients undergoing noncardiothoracic surgery. Recorded measurements of blood pressure, heart rate, arterial oxygen saturation, and temperature were electronically analyzed for deviations from defined limits. The computer system also was used by anesthesiologists to report voluntarily those deviations as intraoperative incidents. For each electronically detected incident: 1) the complete automated anesthesia record was examined by two senior anesthesiologists who, by consensus, eliminated case records with artifact or in which context suggested that the incident was not clinically relevant, and 2) the anesthesia information management system database was checked for voluntary reporting. RESULTS: In 473 automated anesthesia records, 494 incidents were found by electronic scanning of 5,454 automated anesthesia records. Sixty intraoperative incidents were eliminated, 25 due to artifact and 35 due to context. When the remaining 434 intraoperative incidents were checked for voluntary reporting, 18 (4.1%) matching voluntary reports were found. All intraoperative incidents that were reported voluntarily also were detected by electronic scanning. Based on a 10% sample, the sensitivity rate of electronic scanning was 97.2% (35/36), and the specificity rate was 98.4% (427/434). Among 413 cases with electronically detected intraoperative incidents, there were 29 deaths (7.0%), whereas there were only 79 deaths (1.6%) among 5,041 cases without incidents (chi 2 = 58.5, P < 0.001). CONCLUSIONS: The use of an anesthesia information management system facilitated analysis of intraoperative physiologic data and identified certain intraoperative incidents with high sensitivity and specificity. A low level of compliance with voluntary reporting of defined intraoperative incidents was found for all anesthesiologists studied. Finally, there was a strong association between intraoperative incidents and in-hospital mortality.

Purification, primary structure, and immunological characterization of the 26-kDa calsequestrin binding protein (junctin) from cardiac junctional sarcoplasmic reticulum.

Previously we identified a protein of apparent M(r) = 26,000 as the major calsequestrin binding protein in junctional sarcoplasmic reticulum vesicles isolated from cardiac and skeletal muscle (Mitchell, R. D., Simmerman, H. K. B., and Jones, L. R. (1988) J. Biol. Chem. 263, 1376-1381). Here we describe the purification and primary structure of the 26-kDa calsequestrin binding protein. The protein was purified 164-fold from cardiac microsomes and shown by immunoblotting to be highly enriched in junctional membrane subfractions. It ran as a closely spaced doublet on SDS-polyacrylamide gel electrophoresis and bound 125I-calsequestrin intensely. Cloning of the cDNA predicted a protein of 210 amino acids containing a single transmembrane domain. The protein has a short N-terminal region located in the cytoplasm, and the bulk of the molecule, which is highly charged and basic, projects into the sarcoplasmic reticulum lumen. Significant homologies were found with triadin and aspartyl beta-hydroxylase, suggesting that all three proteins are members of a family of single membrane-spanning endoplasmic reticulum proteins. Immunocytochemical labeling localized the 26-kDa protein to junctional sarcoplasmic reticulum in cardiac and skeletal muscle. The same gene product was expressed in these two tissues. The calsequestrin binding activity of the 26-kDa protein combined with its codistribution with calsequestrin and ryanodine receptors strongly suggests that the protein plays an important role in the organization and/or function of the Ca2+ release complex. Because the 26-kDa calsequestrin binding protein is an integral component of the junctional sarcoplasmic reticulum membrane in cardiac and skeletal muscle, we have named it Junctin.

Monoclonal autoantibodies promote central nervous system repair in an animal model of multiple sclerosis.

Susceptible strains of mice infected intracerebrally with Theiler's murine encephalomyelitis virus develop a chronic, progressive, immune-mediated CNS demyelinating disease similar both pathologically and clinically to multiple sclerosis. Previous reports indicated that polyclonal immunoglobulins from mice injected with homogenized spinal cord promote CNS remyelination when given to SJL/J mice chronically infected with Theiler's virus. To explore further both the mechanism(s) and potential therapeutic usefulness of antibodies in the treatment of CNS demyelinating diseases, we made a panel of monoclonal antibodies derived from splenocytes of SJL/J mice injected with homogenized spinal cord, and screened them for their autoantigen-binding capability. Monoclonal IgM autoantibodies from two clones, designated SCH94.03 and SCH94.32, promoted fourfold more CNS remyelination than controls when given to chronically infected SJL/J mice. CNS remyelination, assessed morphologically by the presence of abnormally thin myelin sheaths relative to axonal diameter, correlated with the absence of clinical disease progression. In titration experiments, treatment with SCH94.03 and remyelination had a positive dose-response relationship, and as little as 10 micrograms of antibody promoted remyelination. Both SCH94.03 and SCH94.32 showed multiorgan autoreactivity, and recognized both surface and cytoplasmic determinants on glial cells. We propose that this model provides a unique system to elucidate the mechanism(s) and test the reparative potential of autoantibodies in the treatment of CNS injury.

Salivary cortisol levels in socially phobic adolescent girls.

Anxiety disorders such as social phobia (SP) often have their onset during adolescence and frequently precede the onset of major depression. Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis is well-documented in major depression. Consequently, there is considerable interest in HPA function in anxiety disorders. We examined salivary cortisol levels in 27 SP adolescent girls and 21 matched controls during normal daily activities, and immediately before and after a modified Trier Social Stress Test (TSST). Both SP subjects and controls showed significant elevations in cortisol levels prior to the TSST, and prior to attending school. These results suggest that salivary cortisol is a sensitive measure of anticipatory anxiety, but we failed to find significant differences between SP subjects and controls.

Effects of in-season (5 weeks) creatine and pyruvate supplementation on anaerobic performance and body composition in American football players.

The purpose of this investigation was to study the efficacy of two dietary supplements on measures of body mass, body composition, and performance in 42 American football players. Group CM (n = 9) received creatine monohydrate, Group P (n = 11) received calcium pyruvate, Group COM (n = 11) received a combination of calcium pyruvate (60%) and creatine (40%), and Group PL received a placebo. Tests were performed before (T1) and after (T2) the 50 week supplementation period, during which the subjects continued their normal training schedules. Compared to P and PL, CM and COM showed significantly greater increases for body mass, lean body mass, 1 repetition maximum (RM) bench press, combined 1 RM squat and bench press, and static vertical jump (SVJ) power output. Peak rate of force development for SVJ was significantly greater for CM compared to P and PL. Creatine and the combination supplement enhanced training adaptations associated with body mass/composition, maximum strength, and SVJ; however, pyruvate supplementation alone was ineffective.