Examination of human stomach biopsies, saliva, and dental plaque for Campylobacter pylori.

To examine possible sources of Campylobacter pylori and to determine the routes by which it is transmitted to the human stomach, samples of dental plaque and saliva from 71 patients undergoing endoscopy in addition to stomach biopsies were collected and cultured on selective noninhibitory Skirrow medium. A total of 29 (40.8%) of the stomach biopsies yielded C. pylori. None of the saliva samples and only one of the dental plaque samples was found positive for C. pylori, and thus neither saliva nor dental plaque could be implicated as a significant reservoir of this organism.     

Nucleotide sequence of a resistance breaking mutant of southern bean mosaic virus

Summary.  SBMV-S is a resistance-breaking mutant of an Arkansas isolate of the bean strain of southern bean mosaic virus (SBMV-B^ARK) that is able to move systemically in Phaseolus vulgaris cvs. Pinto and Great Northern, whereas the wild-type SBMV-B^ARK causes local necrotic lesions and is restricted to the inoculated leaves of these hosts. Sequence analysis of the 4136 nucleotide genomes of SBMV-B^ARK and SBMV-S revealed seven nucleotide differences, but only four deduced amino acid changes. A single amino acid change occurred in the C-terminal region of the putative RNA-dependent RNA polymerase and three differences were identified in the N-terminal portion of the virus coat protein. SBMV-B^ARK and SBMV-S were compared with other sobemoviruses and were found to contain a high level of nucleotide sequence identity (91.3%) to SBMV-B. Unlike SBMV-B however, SBMV-B^ARK and SBMV-S contained four putative overlapping open reading frames, making them more similar in genome organization to the cowpea strain, SBMV-C. The possibility exists that mutations or even errors, that resulted in mis-identification of open reading frames, occurred in previously published information on nucleotide sequence and genomic organization for SBMV-B. Received November 23, 1997 Accepted June 16, 1998     

Rubidium and cesium as host blood-markers to study multiple blood feeding by mosquitoes (Diptera: Culicidae)

We have developed an experimental technique to quantify multiple blood feeding by mosquitoes during a single gonotrophic cycle on conspecific or closely related vertebrate hosts. Rubidium and cesium were detected in mosquitoes that fed on chickens injected with these elements 3 d earlier. Experimentally induced double blood meals were confirmed by the presence of both rubidium and cesium in individual mosquitoes. Multiple blood feeding by Culiseta melanura also was demonstrated in nature using this technique. This was the first simultaneous use of two alkali metals as host blood-markers for the study of mosquito blood-feeding behavior.     

Study on a family with anderson--Fabry''s disease and associated familial spastic paraplegia.

A family in the north-east of England with Anderson--Fabry's disease is presented. Alpha-galactosidase activity in plasma and white cells was significantly reduced in three adult male members of the family. One of them had an abnormal chromosome karyotype pattern with an extra Y chromosome (47,XYY) and he was clinically less severely affected than his brothers. Coincidentally five other members of the family suffered from a form of familial spastic paraplegia.     

Home Versus Clinic Blood Pressure Measurements

To evaluate the cost effectiveness of home versus clinic blood pressure 11 patients with mild untreated hypertension were instructed in self-measurement of blood pressure with mercury manometers. The lower total cost of using home readings as well as problems of bias and blinding are discussed. Home blood pressure is a promising technique for clinical and epidemiologic research.     

Improved recovery of highly enriched mitochondrial fractions from small brain tissue samples

The investigation of mitochondrial abnormalities in brain commonly requires isolation of these organelles from small tissue samples. We have modified a mitochondrial isolation procedure based on Percoll density gradient centrifugation to increase the proportion of the total mitochondrial pool recovered while reducing contamination with synaptosomes and related structures containing cytoplasm. Initially, myelin was removed by centrifugation in 12% Percoll in isotonic buffer. The pellet was resuspended, treated with digitonin to break up synaptosomes and similar structures and subjected to discontinuous Percoll density gradient centrifugation. The mitochondrial fraction obtained from this procedure was highly metabolically active and well coupled, exhibiting respiratory control ratios above 5. The recovery of mitochondrial markers using a single rat forebrain as starting material was approximately 18% to 21%. When small tissue samples (approximately 50 mg wet weight) were used as starting material the recovery of the mitochondrial marker was approximately 16%. The ratio of recovery of a mitochondrial marker to the cytoplasmic marker lactate dehydrogenase exceeded 200 in preparations from a single rat forebrain. This is substantially greater than values reported for previously published procedures reflecting both an improved yield of mitochondria and a reduction in cytoplasmic contamination.     

Children and adolescents in the psychiatric emergency setting.

Emergencies in child and adolescent psychiatry are not uncommon, occur in a variety of settings, and require referral to resources offering different levels of care. Clinicians must be familiar with basic tenets of emergency assessment and treatment whether practicing alone in a rural area or as part of an interdisciplinary team in a busy urban hospital. Recommendations for future research include gathering more extensive epidemiologic data and data regarding practice patterns nationwide and conducting more psychopharmacologic research into the management of patients with acute agitation, aggression, and violence. In addition, outcome data to support provision of necessary inpatient and outpatient services must be collected. The development of successful strategies to prevent psychiatric emergencies in children and adolescents is equally important.