Hypokalaemic myopathy following ileal resection

A patient developed an acute hypokalaemic myopathy due to persistent diarrhoea 4 months after a resection of ileum and a right hemicolectomy for carcinoma of the colon. The need for potassium supplements in the management of chronic diarrhoea following ileal resection is emphasized and the method of potassium replacement discussed.

A comparative study of four methods of evaluating velopharyngeal adequacy

Forty-eight subjects with repaired palatal clefts were divided into three major groups on the basis of speech symptoms and were examined for velopharyngeal valving integrity by means of the R-D nasal manometer, pressure-flow techniques, the Hunter oral manometer, and videofluoroscopy. Videofluoroscopy appeared to provide data that most nearly agreed with predictions of valving made from speech. The Hunter oral manometer was the least useful of the four techniques.

Narcotics addiction treatment: behavioral methods concurrent with methadone maintenance

Methadone maintenance patients were assigned among four treatment cells involving contingency management, emotionally-based behavior therapy, a combination of these, or a control condition receiving counseling but no behavioral treatment. With 60 patients who remained in treatment at least 6 months, treatment outcomes were compared using objective measures: hours employed, urinalysis results, and counseling participation. No significant differences were found between modalities. Case studies suggested that under appropriate conditions, contingency management might reduce illicit drug use. It is suggested that focused experimental studies may be more productive than broad clinical outcome evaluations.

Simple butyrate esterase stain for monocytes

The esterases used to identify monocytes are best demonstrated using alpha-naphthyl butyrate as substrate. However, the reagents commonly used for this stain are time-consuming to prepare and are unstable. This report describes a quick, easy, and reproducible staining method using stable reagents which are readily available commercially but which may also be prepared in the laboratory.

Physiological apparatus in the wellcome Museum 2. The dudgeon sphygmograph and its descendants

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Echocardiographic differentiation of partial and complete atrioventricular canal

Retrospective examination of echocardiograms was performed in 34 patients with persistent atrioventricular (A-V) canal who had undergone cardiac catheterization. Characteristic findings in 16 patients with partial A-V canal were lack of continuity of mitral and tricuspid valves, paradoxical interventricular septal motion, definite E and A waves of the mitral valve anterior leaflet (MVAL) echoes and late systolic anterior motion of the mitral valve. Eighteen patients with persistent A-V canal had an interventricular communication and were classified as having the complete form. They characteristically had continuous mitral and tricuspid valves, normal interventricular septal motion, disorganized MVAL echoes, and normal systolic mitral valve motion. Combining these findings allowed differentiation of 31 of the 34 patients (91%) as having partial or complete A-V canal. Determining the presence of a VSD from loss of interventricular septal echoes was unsatisfactory. The severity of mitral insufficiency could not be estimated from echocardiograms of our patients with partial A-V canal.

Physiological apparatus in the Wellcome Museum. 1. The Marey sphygmograph

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Aortic regurgitation associated with ventricular septal defect. Echocardiographic and hemodynamic observations

Ventricular septal defect is sometimes associated with aortic regurgitation. In this report, an echocardiogram demonstrating dramatic prolapse of the noncoronary cusp into the left ventricular outflow tract and ventricular septal defect in a patient with Down's syndrome and ventricular septal defect, confirmed by angiographic studies, is presented. The echocardiogram supports the concept of anatomic lack of support of the aortic ring due to a deficient septum and hemodynamically significant flow of blood to the right ventricle through the ventricular septal defect, resulting in trauma to aortic cusps and prolapse.

Epidemiologic screening: a method to add efficiency to epidemiologic research

The concept of power loss through misclassification is well known. A simple method developed here yields a means for determing by how much power is lost. The method provides the basis for the development of an efficient screening methodology for the identification of high and low risk cohorts. This screening procedure is built on the well established retrospective cohort methodology and utilizes general records of mortality and morbidity for determination of the frequency of disease in the exposed and non-exposed cohorts. The size and power of the testing procedure compare favorably to that of a study with complete follow-up, while reducing the time and costs of study. This is particularly important in aiding epidemiologists in determining research and program priorities from among many areas of possible concern.

Identification of a viral protein involved in post-translational maturation of the encephalomyocarditis virus capsid precursor

Translation of encephalomyocarditis virus RNA in a cell-free system from uninfected Krebs ascites cells results in the synthesis of a major polypeptide product with a molecular weight of approximately 112,000. In contrast, when the viral RNA is translated in a cell-free system from virus-infected cells, this polypeptide is absent and the largest polypeptide produced has a molecular weight of about 100,000. This latter polypeptide comigrates on sodium dodecyl sulfate-gels with in vivo virus capsid precursor A, and the two have identical patterns of CNBr-generated peptides. A polypeptide having a molecular weight of 12,500 is also a major translation product in the system from infected cells (but not from uninfected cells). This polypeptide appears to be generated by cleavage of the NH-2-terminal portion of the viral RNA-dependent polypeptides by a proteolytic activity present in the infected cell-free system. This proteolytic activity copurifies with the 23,000-molecular weight viral capsid protein gamma, found in infected cells, through chromatography on DEAE-cellulose and cellulose phosphate. This suggests that gamma is itself a proteolytic enzyme involved in maturation of the viral capsid precursor.

Encephalomyocarditis virus infection of mouse plasmacytoma cells. I. Inhibition of cellular protein synthesis

Mouse plasmacytoma ascites tumor cells (MOPC 460) were efficiently infected with encephalomyocarditis virus. Inhibition of host protein synthesis was evident after 2 h and complete by 4 h postinfection. The mechanism by which virus infection results in inhibition of host cell protein synthesis was studied in vitro. Cell-free protein-synthesizing systems, prepared from uninfected and infected cells, were found to be equally active with respect to their abilities to translate cellular and viral mRNAs. The plasmacytoma cell-free system was also shown to be insensitive to the addition of double-stranded viral RNA. Host cellular mRNA was isolated from uninfected and infected cells. No difference in the amount or size distribution of the mRNA was detected. However, the mRNA from infected cells was translated only 46 to 49% as actively as that from uninfected cells. mRNA isolated from cells in which initiation of protein synthesis was inhibited with pactamycin was similarly inactivated. Simultaneous addition of viral RNA and cellular mRNA to the plasmacytoma cell-free system resulted in a complete suppression of the translation of the cellular message, whereas viral RNA was translated normally.

Encephalomyocarditis virus infection of mouse plasmacytoma cells. II. Effect on host RNA synthesis and RNA polymerases

The effect of encephalomyocarditis virus infection of MOPC 460 mouse plasmacytoma cells on host RNA synthesis and RNA polymerases was investigated. Consistent with work performed in other virus host systems, rates of RNA synthesis appeared to be inhibited in infected cells, whereas RNA degradation appeared normal. These results were further extended with isolated nuclei, in which distinct RNA polymerase activities could be studied under conditions where problems with RNA turnover and endogenous nucleotide pool sizes were insignificant. Endogenous nuclear RNA polymerase II activity was inhibited early postinfection and at 1 to 2 h prior to endogenous RNA polymerase I plus III activity. However, the solubilized enzymes were fully active with exogenous DNA as template. In fact, the levels of RNA polymerases I, II, and III, isolated from infected cells and nuclei, were indistinguishable from levels in uninfected cells and nuclei at each stage of their partial purification procedure. The chromatographic properties of the enzymes on DEAE-Sephadex were also unaltered. Furthermore, the RNA synthetic activity of these isolated enyzmes, or of nuclei isolated from uninfected cells, was resistant to extracts of nuclei or of cytoplasmic fractions from infected cells. These results are discussed in terms of a possible inhibition of RNA synthesis in vivo at the level of transcription initiation.

The mechanism of viral replication. Structure of replication complexes of encephalomyocarditis virus

The structure of the purified replicative intermediate of encephalomyocarditis virus was determined by electron microscopy. Approximately 80% of the replicative intermediate complexes were characterized by a filament of double-stranded RNA of widely variable length, which had a "bush" of single-stranded RNA at one end. In many examples one or more additional single-stranded bushes were appended internally to the double-stranded RNA filament. These results support the view that before deproteinization, replicative intermediate contains little if any double-stranded RNA.