Search PubMed⌕ Search

Biomedical subjects

S Friedman

Publications and source records attributed to S Friedman.

At least 415 records · Page 23Linked to original sources

Inclusions in red blood cells containing Hb S or Hb C.

To demonstrate and characterize red cell inclusions in 101 persons with Hb S or Hb C disorders three methods were used: (1) examination of unstained blood smears by dark field microscopy (DFM), (2) examination of blood smears after acid elution and staining (AE), and (3) measurement of membrane-associated denatured haemoglobin (MADH) in ghosts. The control group had inclusions in less than 5% of red cells by DFM and AE and the mean percentage of MADH per total cellular Hb was 0.030+/-0.016%. The highest percentages of red cells with inclusions and of MADH were present in clinically severe haemoglobin disorders, e.g. homozygous sickle cell disease (Hb SS) with less than 10% Hb F and Hb SOArab, with successively lower percentages in moderate to severe disorders, e.g. Hb SS-alpha thalassaemia, Hb-S-beta0 thalassaemia, Hb SC disease, and Hb SS with more than 10% Hb F, indicating agreement in results by three methods. In asymptomatic or mild disorders, e.g. Hb-S-beta+ thalassaemia, Hb CC, Hb AC and Hb AS, the results by AE and measurements of MADH were the same or similar to those in controls, while those by DFM were different. Of 56 patients with Hb SS or Hb SC, the group with functional asplenia had higher percentages of MADH and of red cells with inclusions than those with functioning spleens. Our study suggests that inclusions in sickling disorders may be due to denatured Hb S, with AE being the more accurate method for visualizing these inclusions, as results by this method correlate better with the amount of MADH than those by DFM.

Adolescent↗

Coarctation resection in children with Turner's syndrome: a note of caution.

Eight children were recognized to have Turner's syndrome, among 353 patients over 1 year of age who had undergone surgical treatment for coarctation of the aorta. Of these eight children, three developed a significant perioperative hemorrhage from aortic rupture, resulting in one death and one instance of paraparesis related to a period of prolonged hypotension. In two of the other five patients with Turner's syndrome, a decision was made to perform an angioplasty rather than a resection of the coarctation because of apparent friability of the aortic wall. In contrast, only one of the 345 patients without Turner's syndrome died as a result of surgical treatment, and none developed spontaneous perioperative aortic rupture or neurologic deficit. This experience suggests that the operative risk for coarctation of the aorta in this subgroup of patients is considerably greater than that in patients without Turner's syndrome (p < 0.001). Special precautions should include use of rubber-jaw vascular clamps, choice of technique to avoid tension at the anastomotic suture line, and careful control of systemic blood pressure intraoperatively and postoperatively. Indications for surgical treatment of coarctation as well as the type of operative procedure must be individualized cautiously in patients with Turner's syndrome.

Adolescent↗

The effect of chemical modification of 3-(3-amino-3-carboxypropyl)uridine on tRNA function.

The minor base 3-(3-amino-3-carboxypropyl)uridine (acp3U) in Escherichia coli tRNAPhe was acylated with the N-hydroxysuccinimide esters of acetic, phenoxy-acetic, and naphthoxyacetic acid, as well as the ester of 5-dimethylaminonaphthalene-1-sulfonyl (dansyl)-glycine. The derivatives of tRNAPhe formed were all capable of accepting phenylalanine. There were only minor effects on the kinetic parameters of these derivatives for E. coli phenylalanyl-tRNA synthetase. There was no effect on the ability of tRNAPhe to participate in poly(U)- or poly(ACU)-directed polypeptide synthesis or in the poly(U)-stimulated binding to E. coli ribosomes. The rate of photodynamic cross-linking of 4-Srd 8 to Cyd 13 was decreased in tRNAs containing the acetyl and dansyl-glycyl derivatives of acp3U, indicating that acylation of this base may perturb the tertiary structure of the tRNA. This base in tRNAPhe does not appear to play any role in the known biological functions of tRNAPhe.

Acylation↗

Hereditary spherocytosis with normal osmotic fragility after incubation. Is the autohemolysis test really obsolete?

Two patients in two families had hereditary spherocytosis but lacked a population of RBCs with increased osmotic fragility after incubation. The diagnosis in each patient was confirmed by the presence of splenomegaly, spherocytosis, reticulocytosis, and abnormal autohemolysis corrected by glucose. Sodium flux studies showed increased sodium permeability of the RBC membrane in one patient and normal permeability in another. Hereditary spherocytosis was also present in three other family members of patient 2. The autohemolysis test is of value in confirming the diagnosis in patients with hereditary spherocytosis and normal incubated osmotic fragility.

Child↗

beta-Blockade therapy for supraventricular tachyarrhythmias after coronary surgery: a propranolol withdrawal syndrome?

A high incidence of cardiac arrhythmias and hypertension has been noted after coronary artery bypass surgery in patients previously treated with oral propranolol. Forty-two patients undergoing coronary bypass surgery had propranolol withdrawal 10 hours before surgery and were randomized into a group treated with propranolol immediately postoperatively, and a nontreatment group. Patients treated with prophylactic propranolol had a significantly lower incidence of postoperative supraventricular arrhythmias compared to patints who received no prophylaxis. All the arrhythmias responded rapidly to 1 mg of intravenous propranolol therapy, whether it was used as a primary treatment or as a supplement to prophylactic propranolol. The findings suggest that (1) there is a high incidence of supraventricular arrhythmias and sinus tachycardia after coronary artery bypass which might reflect an abrupt propranolol withdrawal, and (2) that perioperative prophylactic or supplementary propranolol therapy will successfully prevent or treat most of these arrhythmias.

Coronary Artery Bypass↗

Comparison of thyroid stimulators and thyroid hormone concentrations in the sera of pregnant women.

To clarify the role of various thyroid stimulators in normal human pregnancy, we measured serum TSH, chorionic TSH (hCT), hCG, bioassayable thyroid-stimulating activity, T4, T3, T3 uptake, free T4 and free T3 indexes, free T4, and free T3 by dialysis in 339 serum samples from pregnant women at various intervals of pregnancy and in 40 normal female controls. Serum T4 and T3 and free T4 and free T3 indexes were significantly elevated throughout pregnancy in comparison with controls. Free T4 concentration was elevated after 10 weeks of pregnancy and free T3 concentration was elevated at 13--20 weeks. Bioassayable thyroid-stimulating activity was elevated from 9--16 weeks when serum hCG concentrations were highest. Serum TSH levels were significantly lower at 9--12 weeks compared with the rest of pregnancy. hCT was detected in only 35% of sera tested; the mean detectable value was 0.60 +/- 0.04 (SE) microU/ml; only 15% of the detectable values exceeded 1 microU/ml. The level of hCG correlated with bioassayable thyroid-stimulating activity (P less than 0.01). The data indicate that hCT is not a significant thyroid stimulator. We propose that hCG, as a weak thyroid stimulator, causes a modest rise in free thyroid hormone levels early in pregnancy which in turn causes a modest reduction in pituitary TSH secretion.

Biological Assay↗

A simple microchromatographic column for determination of hemoglobins A1a + b and A1c.

A simple microchromatographic homemade column was devised for the measurement of glycosylated minor hemoglobin fractions. The mean and one standard deviation of hemoglobins A1a + b, A1c and A1a + b + c determined by the homemade column in 150 nondiabetic controls and 56 juvenile onset insulin-dependent diabetics were 2.6 +/- 0.5%, 6.0 +/- 1.0%, 8.6 +/- 1.1%, 3.3 +/- 0.9%, 13.7 +/- 2.2% and 16.9 +/- 2.8% respectively. A twofold increase in hemoglobins A1c and A1a + b + c levels was observed in the diabetics as compared to the non-diabetic controls suggesting that the homemade column is valid for the measurement of all three glycosylated hemoglobin fractions and assessment of blood glucose control in diabetic patients. The homemade column procedure yields accurate and reproducible results, is simple to perform, inexpensive, relatively rapid and may be used in the routine clinical laboratory. Hemoglobin A1a + b + c levels measured by a commercial column in 35 non-diabetic controls and in 56 diabetics showed good correlation (R = 0.91) with hemoglobin A1a + b + c levels determined by the homemade column. The commercial column is valid for the measurement of the combined glycosylated hemoglobin A1a + b + c fraction and may be used in the routine clinical laboratory to assess diabetic control.

Adolescent↗

Studies on vasoocclusive crisis of sickle cell disease. I. Effect of pentoxifylline.

A method was developed to induce and continuously monitor vasoocclusive crisis of sickle cell disease in non-human primates. Pentoxifylline, a phosphodiesterase inhibitory agent, showed significant preventive effect. This may be based on its ability to increase intracellular cAMP levels and consequently to decrease platelet aggregation and to increase red cell deformability.

Anemia, Sickle Cell↗

Treatment of tardive dyskinesia and mania with RBC lithium determinations.

The authors report the usefulness of RBC lithium determinations in managing the treatment of tardive dyskinesia. They present a case report in which manic manifestations and tardive dyskinesia symptoms paralleled the rise and fall of RBC lithium and plasma lithium levels were constant during the period of symptom improvement. They conclude that RBC lithium levels appeared to reflect toxicity, control of mania, and symptom suppression of tardive dyskinesia better than plasma lithium levels alone.

Antipsychotic Agents↗

Localized cerebritis following an esthetic rhinoplasty.

We report a case of Wernicke's sensory aphasia, caused by a localized cerebritis of the left temporal lobe. The condition developed in the second week after an esthetic rhinoplasty. There was an associated small abscess in the right inner canthal area.

Adult↗

Correlation between 3',5', c-AMP levels and thyrotropin in separated rat pituitary thyrotropic cells.

The correlation between 3',5', c-AMP levels, TSH content and secretion of separated thyrotropic cells was studied. Incubation of the separated cells with 1, 10 and 100 ng of TRH does not change the 3',5',c-AMP levels, despite the significant rises of the TSH level. Dibutyryl c-AMP causes rise in TSH content, with no indication of its secretion. PGE2 10(-5) increased 3'5',c-AMP levels with no change in the content or secretion of TSH in separated thyrotropic cells.

Animals↗

A simple test for detection of sickle hemoglobin in the neonatal period.

The ease of denaturation by shaking of a solution of oxyhemoglobin S (oxy-Hb S) forms the basis for a simple and reliable test for confirmation or rapid detection of Hb S in children and adults. Comparison of results of this test with those from agar gel electrophoresis in capillary blood samples from 187 black neonates at 2 to 7 days of life showed no overlap of the amounts of hemoglobin precipitated between the group of neonates with Hb S (5.7--12.0%) and that without Hb S (0--4.7%). These results indicate that the shaking test, by virtue of being simple, reliable and inexpensive, may be used to detect and confirm Hb S in large numbers of neonates before their discharge from the nursery.

Anemia, Sickle Cell↗