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Biomedical subjects

S Holland

Publications and source records attributed to S Holland.

At least 109 records · Page 6Linked to original sources

Effects of divalent metal cations on composition and neoplasia-specific antigenicity of chromatins.

The antigenicity and composition of chromatins differ markedly in chromatin preparations obtained by different procedures. Rat Novikoff hepatoma chromatin (NC) obtained by the "salt precipitation" and the micrococcal nuclease digestion procedures using significant levels of EDTA and NaCl each shows a common complement fixation (CF) capacity, exceeding chromatin preparations obtained from normal rat liver when tested with rabbit antisera raised to dehistonized NC. In contrast, "structured" NC preparations, which have been postulated to retain a native physical conformation, show minimal CF capacity when tested with the same antiserum but show high CF following elution of histones. While further progressive elution of non-histone proteins (NHPs) did not alter the CF capacity per unit DNA, the completely separated DNA and NHP fractions each showed minimal CF. The data suggest that the antigens detected in the CF assay predominantly represent an artifactual but specific complex of DNA and NHP arising from a denaturation of the native chromatin following elution of metal ions or histones. A qualitatively similar profile of NHPs in salt-precipitated NCs shows a range of total protein/DNA ratios, suggesting that the NHPs found in chromatin preparations may not be intrinsic to the native chromatin structure.

Animals↗

The interaction of anthraquinone dyes with the plasmid-mediated OXA-2 beta-lactamase.

Although beta-lactamases do not require any nucleotide co-substrates, the OXA-2 type is inhibited competitively by Cibacron Blue 3GA, and by other anthraquinone dyes, including some simpler compounds with no side chain. The enzyme causes a red shift in the spectrum of Cibacron Blue. The beta-lactamase can be adsorbed in Blue Sepharose and specifically eluted by benzylpenicillin. These results indicate that the binding of anthraquinone dyes is a specific effect similar to that seen with many nucleotide-binding enzymes.

Anthracenes↗

pH homeostasis during cardiopulmonary resuscitation in critically ill patients.

We investigated the effect of repeated administration of sodium bicarbonate on acid-base balance and serum chemistry in a group of patients who developed cardiac arrest. A mixed acidosis persisted throughout the duration of resuscitation in the majority of patients in spite of the large ventilatory volume and multiple doses of bicarbonate they received. However, the repeated administration of bicarbonate prevented a severe fall in serum pH. Our study demonstrated the beneficial role of bicarbonate in the treatment of metabolic acidosis associated with cardiac arrest of prolonged duration. Analysis of our data strongly indicated that the primary factors which determine the serum pH during cardiopulmonary resuscitation are the duration of circulatory arrest, adequacy of ventilation and circulation, pH immediately before arrest, and quantity of bicarbonate administered and its volume of distribution in the various fluid and tissue compartments.

Acid-Base Equilibrium↗

Gateway Houses: effectiveness of treatment on criminal behavior.

Arrest rates for the year preceding admission to and the year following discharge from the Gateway Houses program were determined for three groups of former residents: Group 1, early dropouts; Group 2, late dropouts; and Group 3, persons who completed treatment. Data were obtained from police records. Results showed that arrest rates for the groups were comparable prior to admission but significantly different following discharge. Group 1 showed no change in arrest rates from the year prior to admission to the year following discharge, Group 2 showed an 81% reduction in arrest rates, and Group 3 showed a 97% reduction in arrest rates. It is argued that change in criminal behavior occurred as a function of treatment.

Adolescent↗

The incidence of gonorrhoea in urban Rhodesian Black women.

The incidence of gonorrhoea in urban Black women seen in an antenatal clinic, a gynaecological clinic and a family planning clinic, was studied. Swabs taken from the urethra, endocervix and rectum were cultured by means of the Clinicult system. The overall incidence of gonorrhoea was 9.7%. In the antenatal clinic the incidence was 2%, in the gynaecological clinic it was 11% and in the family planning clinic it was 12%.

Black or African American↗

Malarial lung: report of a case from Africa successfully treated with intermittent positive pressure ventilation.

We describe the first recorded case from Africa of malarial lung, acute pulmonary insufficiency in Plasmodium falciparum malaria. The patient was successfully treated with intermittent positive pressure ventilation (IPPV). There was heavy parasitemia, preceding cerebral complications and rapid onset of pulmonary edema in the absence of fluid overload or cardiac failure. A further complication of polyuria from tubular dysfunction developed whilst the patient was being ventilated. IPPV may have an important place in the management of this rare and usually fatal complication of falciparum malaria.

Adult↗

Hemoglobin Jackson, alpha 127 (H10) Lys replaced by Asn.

A new hemoglobin mutant was detected as a fast-moving variant on cellulose acetate electrophoresis at pH 8.4. The mutation is in the alpha-chain at position 127, where lysine is substituted by asparagine. This is an external residue, and mutation at this site does not lead to any altered physiologic function of the hemoglobin.

Adult↗

Use of blood specimens collected on filter paper in screening for abnormal hemoglobins.

Both cellulose acetate electrophoresis and citrate agar electrophoresis were performed on 834 blood samples collected on filter paper in Jamaica and shipped for testing to the National Hemoglobinopathy Standardization Laboratory at the U.S. National Center for Disease Control. Additionally, 30 blood samples collected locally were stored on filter paper, in microhematocrit capillary tubes, and as whole blood specimens; at selected times the samples were tested for stability to determine the best sample-collection technique for hemoglobin electrophoresis. Results were most nearly accurate when both cellulose acetate electrophoresis and citrate agar testing were used. The methods are easy to perform, but results are unreliable if the blood samples on filter paper are stored at 4 degrees C for longer than two weeks before they are tested.

Agar↗

Comparison of results for quantitative determination of morphine by radioimmunoassay, enzyme immunoassay, and spectrofluorometry.

The quantitative results (accuracy and precision) for determination of opiates by radioimmunoassay (RIA), enzyme immunoassay (EMIT), and spectrofluorometry on split samples are compared. A variety of physiological samples were studied, including random urine from a methadone maintenance clinic and postmortem urine, blood, bile, brain, and lung tissue from heroin-induced or heroin-related deaths. The opiate concentrations detected by the two immunoassay methods were in good agreement with each other in the absence of interfering substances which are believed to react with the antimorphine antibodies. The immunoassay results were in agreement within the relative standard deviation with the fluorometry results in 55% of the urine samples and 80% of the blood samples. The immunological methods are superior to fluorometry for quantitation of morphine in urine samples due to quenching interferences in fluorometry from urine. They were comparable to fluorometry for quantitation of morphine in blood samples.

Adult↗