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Biomedical subjects

S Bernstein

Publications and source records attributed to S Bernstein.

At least 109 records · Page 6Linked to original sources
PubMedDate not supplied

The preparation of estradiol-17 beta sulfates with triethylamine-sulfur trioxide.

Reaction of estradiol-17 beta with triethylamine-sulfur trioxide in pyridine gives exclusively monosulfation at the C17-hydroxyl group with the preparation of 17 beta-sulfooxyestra-1,3,5(10)-trien-3-ol triethylammonium salt (V). The structural assignment suggested by spectroscopic measurements was confirmed by synthetic studies. (Formula: see text) A synthesis of 3-sulfooxyestra-1,3,5(10)-trien-17 beta-ol triethylammonium salt (II) has been accomplished based on the preparation of 17 beta-formyloxyestra-1,3,5(10)-trien-3-ol (XIII). Fusion of the 3-sulfate triethylammonium salt II gives rise to the 17-sulfate triethylamine salt V. The preparation of estradiol-17 beta disulfate has also been achieved.

Chemical Phenomena↗
PubMedDate not supplied

A fusion method for the preparation of steroid sulfates.

A method for the preparation of steroid triethylammonium sulfates is outlined which involves the fusion of triethylamine-sulfur trioxide and steroids. Experimental details are presented which define the process as a thermal equilibrium resulting in the preferential sulfation of aliphatic hydroxyl groups. Sulfation of an aromatic hydroxyl group can be achieved in the absence of an aliphatic hydroxyl group. With excess reagent both types of hydroxyl groups in the same molecule can be sulfated.

Chemical Phenomena↗
PubMedDate not supplied

Role of aerobic gram-negative bacilli in endometritis after cesarean section.

Endometritis is considered to be a polymicrobial infection, involving aerobes, anaerobes, and genital mycoplasmas. Aerobic gram-negative rods make up 7%-25% of all genital isolates, but findings from studies in which special collection techniques were used suggest that many of these may be contaminants from the lower genital tract. Bacteremia occurs in 4%-30% of patients with endometritis, and aerobic gram-negative rods account for approximately 25% of blood isolates. Both selected therapy studies and studies of intrauterine cultures collected at surgery from patients at risk for endometritis suggest the significant role of aerobic gram-negative rods. Among them Escherichia coli is the most common isolate in both genital and blood cultures. Klebsiella pneumoniae and Proteus mirabilis rank next, followed by Enterobacter species. Pseudomonas species account for fewer than 0.6% of genital isolates. Overall, aerobic gram-negative rods are causally involved in 10%-20% of cases of endometritis following cesarean section.

Anti-Bacterial Agents↗
PubMedDate not supplied

Conservation of the low density lipoprotein receptor-binding domain of apoprotein B. Demonstration by a new monoclonal antibody, MB47.

The fact that low density lipoprotein (LDL) from multiple animal species binds to the human LDL receptor suggested that the LDL-receptor binding domain of apoprotein (apo)B must be evolutionarily conserved. To determine if a common receptor domain epitope existed on apo B, we generated a monoclonal antibody that was specific for the LDL-receptor domain of apo B. This was accomplished by using a screening procedure that selected for a hybridoma supernatant that could block specific cellular uptake and degradation of LDL. Western blots showed that this antibody, termed MB47, was specific for apo B-100. Fluid phase assays indicated a high binding affinity (Ka = 4 X 10(9) M-1) and demonstrated that all human LDL particles expressed the MB47 epitope. Scatchard analysis indicated that a maximum of one MB47 molecule bound to each LDL particle. In solid phase assays, antibody MB47 bound to plasma or LDL of multiple mammalian species, including guinea pig, rabbit, pig, dog, cat, seal, whale, bear, and lion, but it did not bind to mouse or rat LDL. In contrast, a rabbit antiserum to LDL and two other anti-apo B monoclonal antibodies, MB3 and MB19, which do not bind to the receptor domain, were specific only for human LDL. LDL from multiple species, including mouse LDL, competed effectively with 125I-human LDL for binding to human fibroblasts. MB47 effectively inhibited uptake and degradation of labeled human, guinea pig, and rabbit LDL by both human and guinea pig fibroblasts. We conclude that antibody MB47 binds to a single receptor domain on LDL and identifies a vital region conserved through mammalian evolution.

Animals↗
PubMedDate not supplied

Determination of fat in vegetable foods.

The fat in vegetable foods--tree nuts, peanuts, sunflower seeds, avocado, and olives--can be determined volumetrically by acid digestion of the material and separation of the fat. The assay can be performed conveniently by using the equipment developed for fat determination of milk (Gerber method). The results agree well with those obtained by Soxhlet extraction. The advantages of using the Gerber method for vegetable foods are simplicity, speed, low operation cost, and elimination of the use of inflammable solvents.

Arachis↗