The perineal groove and canal in males and females--a third look

We present 5 uncommon cases: One case of perineal canal in a female; two cases of perineal groove in females, one with normal anus and another with ectopic perineal anus. Two cases of perineal canal in males. The canal is deep in the perineum, runs forward above the root of scrotum, close to the floor of the urethra (which is normal), and opens on the undersurface of the penis. One of them is associated with covered anus incomplete with anocutaneous fistula as well opening on the scrotal raphe. In all 5 cases the perineal canal or gutter opens posteriorly in the ectodermal anal canal, immediately below the line of anal valves. A third look to the origin of these conditions will be discussed versus the 1st and 2nd looks of Stephens and Chatterjee. Embryological and histopathological studies will support our point of view.

Site-specific cleavage of tobacco mosaic virus RNA: a study of factors influencing the cleavage

DNA oligomer directed ribonuclease H (RNase H) methodology is applied to specifically cleave tobacco mosaic virus (TMV) RNA. Using a synthetic DNA oligomer P(dT8)dCdC, complementary to a region from nucleotide 5545 to nucleotide 5554 at the 3' end of TMV RNA, we have cleaved the RNA at the site of polynucleotides complementary to the DNA oligomer. Factors such as secondary structure of the RNA, concentrations of DNA oligomer, RNase H and magnesium ions in the reaction mixture, and time of incubation were optimized for the RNase H cleavage of TMV RNA-DNA oligomer complex. Denaturation of TMV RNA with 50% dimethyl sulphoxide at 50 degrees C is essential for the site-specific cleavage.

Cholelithiasis and cholecystitis in childhood

In this review of 50 children with gallbladder disease in Houston, Texas, there were an equal number of patients with and without hemolytic disease and a slight predominance of males in both groups. Nearly all had been symptomatic for a prolonged period before diagnosis and cholecystectomy. Common early diagnoses were hemolytic crisis and appendicitis. Ultrasonography has become a very accurate tool for the preoperative evaluation of these children. Once the diagnosis of cholelithiasis is established, elective cholecystectomy is the treatment of choice.

A predator prey model with age structure

A general predator-prey model is considered in which the predator population is assumed to have an age structure which significantly affects it fecundity. The model equations are derived from the general McKendrick equations for age structured populations. The existence, stability and de-stabilization of equilibria are studied as they depend on the prey's natural carrying capacity and the maturation period m of the predator. The main result of the paper is that for a broad class of maturation functions positive equilibria are either unstable for small m or are destabilized as m decreases to zero. This is in contrast to the usual rule of thumb that increasing (not decreasing) delays in growth rate responses cause instabilities.

Chronic cor pulmonale in Iraq

The incidence of chronic cor pulmonale in Iraq has been studied for the first time. Of the total 1,102 cardiac cases admitted to the Medical City Hospital in a 1-year period, 168 patients belonged to this group (15.25%). The most frequent cause is chronic obstructive airway disease. Smoking is thought to be an important factor in the occurrence of obstruction. Chronic and repeated infections during different phases of life are thought to play a major role in the pathogenesis. Occupation and dust probably have no significant effect. Schistosomiasis and tuberculosis are rare causes.

Incorporation of amino acids into soluble and membrane protein fractions of dystrophic hamsters

The incorporation of labelled leucine was measured in protein fractions of muscle in intact control and dystrophic female hamsters and also in cell-free preparations obtained from these animals. The labelling of the soluble sarcoplasmic protein fraction, the microsomal protein fraction and the sarcolemma protein fraction was increased in the dystrophic hindleg muscle. The specific radioactivities of the sarcolemma protein fraction and other fractions were increased markedly relative to that of free leucine in the dystrophic muscle. In cell-free preparations where ribonuclease effects were avoided, the dystrophic muscle exhibited an increased synthesis of peptide bonds.

Thyroid hormone regulation of translation in tadpole tail muscle

Recent in vivo and in vitro studies with polyribosomes from the tail muscle of T3-treated tadpoles establish that this hormone initiates a regulating effect on tadpole tail muscle which operates at the translational level and results in an overall decreased rate of protein synthesis (Saleem, M. & Atkinson, B. G. (1978) J. Biol. Chem. 253, 1378-1384). This hormone-induced decrease in the rate of protein synthesis is partially, if not wholly, due to the presence of a sarcoplasmic factor(s) inhibiting ribosomal translational efficiency. This research employs the use of a reconstituted, cell-free polypeptide synthesizing system as a means to substantiate the presence of an inhibitor and further elucidate the mechanism by which this inhibitory factor(s) depresses protein synthesis. The results of this study further demonstrate the presence of an inhibitor of protein synthesis in the tail muscle sarcoplasm of T3-treated tadpoles and suggest that this depressed synthetic activity results from an interaction of the inhibitor with ribosomal or polyribosomal constituents.

Protein synthesis in muscles from normal and dystrophic hamsters

Homogenates of hindleg muscle were obtained from control and dystrophic male hamsters, 30 and 190 days of age, and were used to prepare the postmicrosomal pH5-supernatant fraction. The activity of this fraction in the incorporation of [14C]phenylalanyl-tRNA into peptides was increased in the dystrophic-muscle preparations. No such increase was found in brain or liver preparations from dystrophic hamsters. The increased capacity for aminoacyl-tRNA binding that was observed in preparations from dystrophic animals is discussed.

Prevalence of coronary heart disease in Pakistani patients suffering from maturity onset diabetes mellitus

In a group of 500 ambulant Pakistani patients suffering from diabetes mellitus, electrocardiographic evidence of coronary heart disease was present in 45 (9%). The frequency was higher in the males (12.1%) as compared to females (7.2%). The male diabetics with coronary heart disease had significantly high mean serum cholesterol values as compared to those without it. A positive family history of ischaemic heart disease, and the presence of small vessel disease as well as hypertension were more frequently associated with coronary heart disease. The overall frequency of hypertension was 21.2 per cent in this group of diabetics.

Isoelectric points and molecular weights of salt-extractable ribosomal proteins

Rat liver ribosomes prepared in low salt buffer contain basic and acidic proteins not found on ribosomes washed in high salt buffer. Proteins extracted from liver ribosomes by 500 mM KCL were characterized by acid urea-polyacrylamide gel electrophoresis, sodium dodecyl sulfate - polyacrylamide gel electrophoresis and gel isoelectric focusing. The salt-solubilized proteins contain 12 polypeptides with a molecular weight over 67000, several polypeptides with molecular weights less than 67 000, and three polypeptides whose molecular weight exceeded 130 000. Ten to 12 of the proteins were basic, and about 24 acidic proteins were partially or wholly extracted from the ribosomes. Four of the acidic proteins have isoelectric points less than 4.5.