PubMed Health⌕ Search

Biomedical subjects

M D Levin

Publications and source records attributed to M D Levin.

53 records · Page 3Linked to original sources
PubMed1984

[Conservative treatment of intestinal invagination in children].

A new method of the conservative treatment of intussusceptions in children by hydrostatic disinvagination with the help of barium enema is described. The durability of the colon was shown to change proportionally to its tone. To make the conservative treatment more efficient and to prevent a perforation of the colon the hydrostatic pressure should depend on the colon tone. Out of 48 patients with acute intestinal invagination 46 children were cured by this method including 2 children with small intestine invagination. In this group of patients there were neither complications nor lethal outcomes.

Barium Sulfate↗
PubMed1982

Structural basis for the deoxyribonucleic acid affinity of bleomycins.

The role of the bithiazole moiety of bleomycin in the interaction of the antibiotic with DNA has been studied by the use of synthetic bithiazole derivatives. The DNA affinity of individual C-terminal (bithiazole) analogues of bleomycin was measured in terms of the ability of these species to block the binding of bleomycin to DNA, as judged by diminution of the DNA degradation that attends bleomycin binding. DNA degradation was monitored both by release of [3H]thymine from radiolabeled PM-2 DNA and by alteration of bleomycin-treated DNA oligomers of defined sequence derived from Escherichia coli plasmid pLJ3. It was found that the affinity of the bithiazole derivatives for DNA depended on the presence of the bithiazole moiety itself but more importantly on the number and spacing of positively charged groups; 2'-(2-aminoethyl)-2,4'-bithiazole-4-[3-[(4-aminobutyl) amino]propyl]carboxamide (14), having three positively charged groups at neutral pH, was a reasonably effective inhibitor of DNA degradation by bleomycin. Consistent with the importance of the spacing of the positively charged groups, tetrapeptide S (12) was found to be significantly less inhibitory toward DNA degradation by bleomycin than tripeptide S, in spite of their equal number of positively charged groups and the greater structural similarity of the former to bleomycin A2. Bleomycin is known to cleave DNA perferentially at certain sequences. It was shown that the inhibitors employed in this study diminished DNA cleavage proportionately at each cleavage site; no alteration was observed in the specificity of cleavage. A number of the bithiazole analogues employed as inhibitors of bleomycin-mediated DNA degradation were also utilized in fluorescence quenching experiments with calf thymus DNA. Consistent with the belief that these species inhibit bleomycin degradation by competitive binding to the DNA substrate, the best inhibitors exhibited the greatest fluorescence quenching upon admixture of DNA.

Bacteriophages↗
PubMedDate not supplied

[Roentgeno-functional studies in ectopia of the anal canal in children].

Analysis of x-ray data on 70 pediatric patients aged one day-15 yrs, was performed. In 55 cases the investigation was conducted before the correction of ectopia of the anal canal, in 11 cases after the previously described operation for forming the anal orifice (FAO), in 4 cases there was stenosis of the anal orifice without ectopia. Radiograms performed during irrigoscopy and (or) with a Foley catheter were assessed. Weakening and then complete incompetence of the puborectal muscle, determining incontinence of feces, were shown to be proportional to age and a degree of stenosis of the colon orifice. A necessity of radical operation in the second half-year of the life or measures to ensure adequate bowel evacuation were shown.

Adolescent↗