TRACHEOTOMY IN BULBAR POLIOMYELITIS

Tracheotomy was performed on 181 of 351 patients with bulbar poliomyelitis. The essential indication for tracheotomy was secretional obstruction of the respiratory tract that could not be relieved by postural drainage and aspiration.Comparison of mortality rates in this series with those of previous series in which tracheotomy was not done in the presence of similar indications, suggests that the procedure may be life-saving in a considerable percentage of cases.Outside the respirator the tracheotomy can be done with or without the aid of the bronchoscope or endotracheal anesthesia tube. When done inside the opened respirator the Bennett flow-sensitive positive pressure machine should be used to supply oxygen to the patient while the respirator is not operating.     

A Two-stage Procedure with Controlled Error Probabilities for Testing Bioequivalence

The procedures currently used for testing the bioequivalence of two drug formulations achieve control over the error probability of erroneously accepting bioequivalence or over the probability of erroneous rejection, but not over both error probabilities. A two-stage procedure that rectifies this drawback is presented, assuming that the performance of the drug is characterized by a normally distributed variate.     

Isolation of Protoplasmic Astrocytes: A Procedure Based on Controlled Trypsin Digestion

Trypsinization of rat brain tissue for shorter (10 min) and longer (60-90 min) periods is shown to yield two distinctly different types of dissociated cell populations. The over-all yield of intact dissociated cells declines when the period of trypsinization exceeds 10 min. Comparison of the types of dissociated cells obtained after different lengths of trypsinization indicates that the protoplasmic astrocytes, which represent the bulk of the neuroglial cells in brain, are highly susceptible to degradation during tissue trypsinization. Based on this observation, a new procedure involving controlled trypsin digestion for tissue disruption and Percoll gradient centrifugation has been developed for the isolation of virtually pure populations of intact protoplasmic astrocytes (97-98% particle purity). Identification of the purified cells is based on morphological, histochemical staining, and biochemical (marker enzyme) characteristics.     

Simple, Inexpensive Procedure for the Disruption of Bacteria

Small volumes (1 to 2 ml) of bacterial cultures, with turbidities ranging from 3 to 10, were disrupted 50 to 90% (measured as a decrease in turbidity) within 2 min, by shaking them on a Vortex-type mixer in the presence of glass beads. This method of disrupton was effective for cells in the following genera: Streptococcus, Lactobacillus, Staphylococcus, Bacillus, and Escherichia. After low-speed centrifugation, the resulting extract can be used as potential sources for enzymes, transforming deoxyribonucleic acids, cell walls, membranes, etc.     

Rapid Synthesis of Oligodeoxyribonucleotides VIII.1 An Improved Procedure for Solid-Phase Oligodeoxyribonucleotide Synthesis Using a Controlled Pore Glass Support and Phosphotriester Chemistry

Abstract

An improved method for solid phase oligodeoxyribonucleotide synthesis is described that uses phosphotriester chemistry, controlled pore glass as support, a new and more stable linkage agent and a better protecting group combination.     

Controlled Trial of Phetharbital,a Non-hypnotic Barbiturate,in Unconjugated Hyperbilirubinaemia

Eleven patients with mild unconjugated hyperbilirubinaemia (Gilbert''s syndrome) took part in a double-blind cross-over trial of phenobarbitone and phetharbital, a non-hypnotic barbiturate. Significant reductions in plasma bilirubin were observed with both drugs, but six patients complained of sleepiness on phenobarbitone, and phetharbital was preferred by most patients. Phetharbital was also effective in the rare severe unconjugated hyperbilirubinaemia of the Crigler-Najjar syndrome (Type 2). Symptoms attributed to Gilbert''s syndrome, including nausea and abdominal pain, were less consistently relieved.     

Standardized, Automated Procedure for Measurement of Serum Hemolytic Complement Activity

In the interest of standardizing and automating complement fixation procedures, an AutoAnalyzer manifold was designed in which the reagents are mixed in proportions similar to that of the Laboratory Branch Complement Fixation test. By bypassing the fixation stage, the manifold proved useful for measuring serum hemolytic complement activity (C'). As many as 21 serum samples per hour can be screened by testing two appropriate dilutions. Normal adult C' titers measured by the automated procedure ranged from 58 to 103 C'H(50) units per ml.