Melanotic neuroectodermal tumour of infancy: report of a case

A case of melanotic neuroectodermal tumour occurring in a seven-month-old male infant is reported. The aetiopathogenesis, clinical features, treatment and prognosis of the condition are discussed. Tumours of the jaw in infancy are extremely rare, and pigmented tumours still rarer. One such case of pigmented tumour of the maxilla is the subject of this report.

Hemolysis following correction of double-outlet right ventricle

A 41/2-year-old child developed a severe degree of intravascular hemolysis within 24 hours after intraventricular correction of double-outlet right ventricle with a Dacron patch. The child developed jaundice, with a serum bilirubin of 4.3 mg. per cent. The hematocrit value fell from 47 to 25 per cent and the reticulocyte count rose to 22 per cent. The hemolysis diminished after 3 weeks and completely disappeared after 6 weeks. We presume that the hemolysis was due to turbulence caused by a long, curved patch and that its disappearance coincided with the endothelialization of the patch. The child is well 3 years after the operation.

Resistance of Salmonella serotypes to chloramphenicol

A total of 704 Salmonella strains isolated from various sources were tested for their resistance to chloramphenicol. The results indicate that 36 out of 46 serotypes, comprising 671 strains (95.4%), were sensitive to chloramphenicol up to a level of 10 mug per ml of medium. Most of the strains were sensitive at concentrations between 2 mug and 4 mug of chloramphenicol per ml of medium. None of the strains isolated from animals, including poultry, was resistant. The results indicate that in India resistance of Salmonella strains to chloramphenicol has not increased over the years though this may have occurred in other parts of the world.

Echocardiographic findings in a patient with primary pulmonary hypertension

This is a report of the echocardiographic findings in a 9-year-old white female with primary pulmonary arterial hypertension confirmed by catheterization and later at autopsy. The reported findings of an absent "a" wave, a flat diastolic E to F slope, and a midsystolic closure of the pulmonic valve were observed. In addition, tricuspid valve prolapse was noted. Prolapse of the tricuspid valve may be part of the mechanism of tricuspid insufficiency in a patient with pulmonary hypertension.

Total correction of type I truncus arteriosus in a 6-month-old infant

A successful correction of type I truncus arteriosus using a 12 mm 'dacron' conduit containing a porcine aortic valve (Hancock) between the right ventricle and the pulmonary artery in a 6-month-old infant is reported. The rationale for the treatment of truncus arteriosus in infancy is discussed.

Colchicine administration to mice: a metabolic and ultrastructural study

A single injection of colchicine has been administered to normal albino mice, and the metabolic effects as well as the hepatic ultrastructural changes resulting from this treatment have been studied at various time intervals. A marked decrease in circulating triglyceride levels was evident 4 hours after colchicine injection and was maximum after 11 hours. It coincided with a marked increase in hepatic triglyceride content. Twenty hours after colchicine administration, plasma triglyceride levels and hepatic triglyceride content had returned to normal values. Similar changes in the levels of circulating proteins were observed although their magnitude was less than that observed for triglycerides. Ultrastructurally, colchicine treatment resulted in the virtual disappearance of the microtubules from the hepatocytes, and in the appearance of many clusters of vesicles containing very low density lipoprotein-like particles which eventually transformed into lipid droplets. These ultrastructural alterations were also completely reversible, the reversibility coinciding with the morphological reappearance of microtubules. Finally, colchicine treatment resulted in marked metabolic changes that are interpreted as representing an attempt, by the organism, to keep adequate energy sources during the period of lack of circulating triglycerides.

Familial hyperlipoproteinemia and gallstones

Of 108 patients with familial hyperlipoproteinemia between the ages of 22 and 85 years (mean, 55.1 years) 46 (42.6%) had cholelithiasis. Among the 53 patients with type II hyperlipoproteinemia 20 (38%) had gallstones; the male:female ratio was 1:2; the mean serum triglyceride value was significantly higher in those with gallstones. Among the 50 patients with type IV hyperlipoproteinemia 25 (50%) had gallstones; the male:female ratio was 1:1; the mean age was significantly higher in those with gallstones. Among the five patients with type V hyperlipoproteinemia one had gallstones. Electrocardiographic evidence of myocardial damage was present in 47 (44%) of the 108 patients; 18 (39%) of the 46 patients with gallstones showed such abnormalities, while 26 (24%) showed sinus bradycardia.

Defective membrane systems in dystrophic skeletal muscle of the UM-X7.1 strain of genetically myopathic hamster

1. The function of mitochondria, sarcotubular membranes (heavy microsomes), sarcolemma and myofibrils from the hind-leg skeletal muscle of about 60- and 150-day-old normal and myopathic (UM-X7.1) hamsters was examined. 2. The mitochondrial calcium uptake as well as mitochondrial phosphorylation and respiratory rates were lower in 60-day-old myopathic skeletal muscle, unlike 150-day-old myopathic animals, when pyruvate-malate and glutamate-malate were used as substrates. However, mitochondria from 150-day-old myopathic animals showed depressed glutamate-dependent respiratory and phosphorylation rates and succinate-supported initial rate of calcium uptake. 3. The microsomal calcium-uptake, but not calcium-binding, and Ca2+-stimulated adenosine triphosphatase (ATPase) activity of the 150-day-old myopathic skeletal muscle were lower than the control values. Although microsomal calcium-binding, calcium-uptake and ATPase activities of the 60-day-old myopathic muscle were not depressed significantly, the initial rate of calcium uptake was less than the control. 4. The sarcolemmal Ca2+-ATPase, but not Mg2+-ATPase or Na+ +K+-ATPase, activity was higher in 60-day-old myopathic muscle whereas the activities of all these enzymes from 150-day-old myopathic animals were higher than the control. On the other hand, the Na+ +K+-ATPase activities from 60- and 150-day-old myopathic animals were inhibited by ouabain to a lesser extent in comparison with the respective control values. 5. The myofibrillar Ca2+-ATPase and Mg2+-ATPase activities as well as inhibition of Mg2+-ATPase due to Na+ and K+ in myopathic muscle were no different from the control values. 6. The results reported here give further support to the view that different membrane systems of the dystrophic muscle are defective.

Genetic and physiological characterization of met15 mutants of Saccharomyces cerevisiae: a selective system for forward and reverse mutations

One hundred and thirty-three spontaneous and induced mutants of the met15 locus in Saccharomyces cerevisiae were characterized with respect to temperature sensitivity, osmotic remediability, interallelic complementation, and suppressibility by amber and ochre suppressors. Forty mutants are osmotic remedial; 17 of these, and no others, are also temperature-sensitive. Seven of 133 mutations are suppressible by an amber suppressor and 11 are suppressible by an ochre suppressor. Seventy percent of the mutants exhibited interallelic complementation, suggesting that the functional gene product of the met15 gene is a multimeric protein. Relative map positions of 30 met15 were estimated from the frequencies of X-ray-induced mitotic reversion of various heteroallelic diploids. All complementing nonsense mutations are located near one end of the gene in contrast to other nonsense mutations which span most of the gene, thus relating the direction of translation of the mRNA with respect to the fine-structure map. Recombination studies indicated that two of 30 mutants contained deletions of the entire met15 locus. -- It was established that a variety of mutational types, including missense, nonsense, and deletions, are recovered with this unique system in which both forward and reverse mutations can be selected on the basis of methyl mercury resistance and methionine requirement of the met15 mutants.

Colchicine-binding protein of the liver. Its characterization and relation to microtubules

Colchicine-binding activity of mouse liver high-speed supernate has been investigated. It has been found to be time and temperature dependent. Two binding activities with different affinities for colchicine seem to be present in this high-speed supernate, of which only the high-affinity binding site (half maximal binding at 5 x 10(-6) M colchicine) can be attributed to microtubular protein by comparison with purified tubulin. Vinblastine interacted with this binding activity by precipitating it when used at high concentrations (2 x 10(-3) M), and by stabilizing it at low concentrations (10(-5) M). Lumicolchicine was found not to compete with colchicine. The colchicine-binding activity was purified from liver and compared with that of microtubular protein from brain. The specific binding activity of the resulting preparation, its electrophoretic behavior, and the electron microscope appearance of the paracrystals obtained upon its precipitation with vinblastine permitted its identification as microtubular protein (tubulin). Electrophoretic analysis of the proteins from liver supernate that were precipitated by vinblastine indicated that this drug was not specific for liver tubulin. Preincubation of liver supernate with 5 mM EGTA resulted in a time-dependent decrease of colchicine-binding activity, which was partly reversed by the addition of Ca++. However, an in vitro formation of microtubules upon lowering the Ca++ concentration could not be detected. Finally, a method was developed enabling that portion of microtubular protein which was present as free tubulin to be measured and to be compared with the total amount of this protein in the tissue. This procedure permitted demonstration of the fact that, under normal conditions, only about 40% of the tubulin of the liver was assemled as microtubules. It is suggested that, in the liver, rapid polymerization and depolymerization of microtubules occur and may be an important facet of the functional role of the microtubular system.

Effects of steroid hormones on developing mouse skin in vitro

Pieces of skin from 13-5- to 15-day-old foetal mice were grown in organ culture in a biological medium with or without the addition of hormonal steroidsmcortisol (7-5 mug/ml) caused thinning of the non-cornified epidermis and flattening of the stratum granulosum after 3 days. By 6 days the epidermis was thinner and hair follicles were regressing, and these changes continued up to 12 days. Administration of corticosterone (5 mug/ml) also produced thinning of the epidermis and regression of the follicles after 6 days. Good differentiation of epidermis and hair follicles was obtained when testosterone (100 mug/ml) was added to the medium. The non-cornified epidermal layers were similar to those of control cultures at 3 days but less than half as thick at 6 days. Hair follicles differentiated as rapidly in medium containing testosterone as in normal medium, but, unlike in the latter medium, also developed sebaceous gland anlagen at 6 days. Some explants in testosterone medium showed signs of sebaceous cell differentiation at 9 days.

Studies in 4-Aminothiazolines. VII. Use of bromomalononitrile in the synthesis of 4-Aminothiazoline-5-carbonitriles and their subsequent hydrolysis byorthophosphoric acid

Bromomalononitrile on condensation with N-substituted thioureas furnished 4-amino-3-aryl(or allyl)-2-imino-4-thiazoline-5-carbonitriles (4). On acetylation in Ac2O/AcOH, (4) gave first mono acetyl derivatives (5) and then diacetyl derivatives (6). Thiazolines (4) and acetyl derivatives (5) underwent hydrolysis with orthophosphoric acid to the corresponding amides (8) and (7) respectively.