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Biomedical subjects

A Friedman

Publications and source records attributed to A Friedman.

At least 253 records · Page 14Linked to original sources
PubMed1980

Glycolipids as potential immunologic adjuvants.

A group of 1-thio-beta-L-fucopyranosides containing hexadecane, 9-octadecene, adamantane, 1,2-diphenyltetrafluoroethane, and 3-hexynyl- and 3,6-dioxaoctylcholesterols were synthesized as potential immunologic adjuvants. Many of these fucosyl lipids and 6-(5-cholesten-3 beta-yloxy)hexyl 1 thioglycosides were found to give good response to subunit A/Victoria influenza virus. Carbohydrates with L-fucose and D-galactose backbones appeared essential for adjuvant activity. Lactose which has a terminal D-galactose moiety was found to be active, whereas L-arabinose which lacks a 5-(hydroxymethyl) group was inactive.

Adjuvants, Immunologic↗
PubMed1980

Hemodynamic and oxygen transport effects of a perfluorochemical blood substitute, fluosol-DA (20%).

Cardiorespiratory measurements were made in a severely anemic patient (hemoglobin concentration of 3.5 g/dl) who was preoperatively given the perfluorochemical blood substitute (Fluosol-DA, 20%). Hemodynamic and oxygen transport variables were monitored, including arterial and mixed venous oxygen content (CaO2 and CVO2) before, during, and after infusion of 1000 ml of Fluosol as well as throughout the intraoperative period. Blood samples revealed a maximum of 2.7% of the perfluorochemical. The CaO2 increased 37% above the CaO2 calculated without Fluosol; i.e., 5.8 +/- 0.1 to 8.1 +/- 0.6 ml/dl, p < 0.01. The cardiac index (CI) decreased from 7.2 +/- 0.2 to 5.9 +/- 0.8 L/min . M2 and the left ventricular stroke work decreased from 67 +/- 6 to 58 +/- 13 g . M/M2, while the oxygen delivery increased, and the total body oxygen consumption (VO2) remained essentially unchanged.l Intraoperatively, 27% of the O2 delivery and 51% of the VO2 were transported by Fluosol. No adverse effects of the fluosol were noted.

Adult↗
PubMed1980

Hemodynamic and cardiometabolic effects of prenalterol in patients with gram negative septic shock.

The hemodynamic effects of prenalterol, a new inotropic agent, were investigated in 10 patients with gram negative septic shock. In four of the patients, coronary sinus blood flow (CSF) and myocardial oxygen and lactate extraction were also determined. After baseline hemodynamic measurements, prenalterol was infused intravenously over a 10-min period to a total dose of 150 micrograms/kg. All patients responded within 15 min after completion of prenalterol infusion by increasing mean arterial pressure from 57 +/- 11 to 75 +/- 20 mmHg (7.58 +/- 46 to 9.97 +/- 2.66 kPa), (+32%), (P less than 0.01) and cardiac index from 2.65 +/- 0.40 to 3.80 +/- 0.47 1.min-1.m-2, (+44%) (P less than 0.001). There was no change in heart rate or systemic vascular resistance, nor were any arrhythmias recorded. The urinary output increased significantly. After prenalterol, CSF increased from 185 +/- 14 to 246 +/- 14 ml.min-1, (+33%), (P less than 0.001) and myocardial oxygen and lactate extraction rose from 19.8 +/- 2.1 to 26.6 +/- 2.1 ml O2.min-1, (+34%) (P less than 0.001) and from 33.2 +/- 2.3 to 44.7 +/- 2.1 mumol.min-1, (+35%), (P less than 0.001), respectively. The total body oxygen consumption increased from 287 +/- 13 to 348 +/- 23 ml O2.min-1, (+21%), (P less than 0.01) and the arterial lactate concentration decreased from 5.61+/- 0.55 to 3.94 +/- 0.16 mmol.l-1, (-30%), (P less than 0.01), suggesting improved tissue perfusion. The results demonstrate that prenalterol is a potent, highly selective inotropic agent inducing the same magnitude of increase in blood pressure and cardiac output as reported for dopamine in septic shock.

Adult↗
PubMed1980

Meningitis. Update of recommendations for the neonate.

Our series of children with meningitis shows an increase in the frequency of isolation of Hemophilus influenzae type B. This increase is most marked among children between one and two months of age. Since H. influenzae was found in five of the seven children between thirty and sixty days of age, we recommend the use of chloramphenicol for the initial treatment of bacterial meningitis after the first month of life. Additionally, our mortality data suggest that early diagnosis and intensive supportive therapy can contribute to a further decrease in the fatality rate of this disease.

Adolescent↗
PubMed1980

Relative importance of bacterial and mammalian nitroreductases for niridazole mutagenesis.

Niridazole is a nitrothiazole anthelmintic agent used to treat schistosomiasis. Its antibacterial activity was found to require the presence of the nitro group; a synthetic desnitro analog was completely inactive. Niridazole was mutagenic for Salmonella tester strains TA1538, TA98, and TA100, suggesting that it was both a frame-shift- and a base substitution-type mutagen. It was effective under both aerobic and anaerobic conditions, while similar testing of the desnitro niridazole produced consistently negative results. Addition of rat liver S-9 fraction under either aerobic or anaerobic conditions did not enhance mutagenicity. However, since bacterial killing limited the dose of niridazole to 0.33 microgram/plate in standard tester strains (1/20 Km for the mammalian liver enzymes), further studies were performed using niridazole-resistant, histidine-dependent mutants derived from strains TA98 and TA100. These mutants were found to be nitroreductase deficient and to resist the mutagenic effects of niridazole, in the presence or absence of S-9, up to concentrations of 10 microgram/plate. In addition, even at niridazole concentrations of up to 100 microgram/plate, rat liver S-9 was ineffective in enhancing the mutagenicity of niridazole. These results suggest that the mutagenicity of niridazole is dependent on its aromatic nitro group and a specific bacterial nitroreductase.

Aerobiosis↗
PubMed1980

Morphological classification, response to therapy, and survival in 263 adult patients with acute nonlymphoblastic leukemia.

Bone marrow smears of 263 protocol patients with acute nonlymphoblastic leukemia (ANLL) and related disorders treated between 1970 and 1978 at MSKCC were reviewed blindly by two pairs of hematomorphologists and classified according to the FAB system. It was found necessary to add one category (MO) for acute undifferentiated leukemia and to define more precise quantitative criteria for the categories M1-M6 based on bone marrow differential counts. Using this modified FAB classification, agreement between the two observer groups based on morphology alone was 69%. Cytochemical stains were essential in establishing the diagnosis in 9%, led to a change of diagnosis by one observer team in 14%, and helped to confirm the diagnosis in 32% of cases. Complete remission rates, remission duration, and survival were not significantly different among diagnostic categories. Myelodysplastic syndromes (MDS: M6, RAEB, CMML; CR rate 48%) and ANLL without differentiation (M0, M1, M5a; CR rate 50%) appeared to do less well than ANLL with partial differentiation (M2, M3, M4, M5b; CR rate 59%) on all three protocols studied. Auer rods were present in 53% of all cases with 63% in the myeloid categories (M1-M4). Auer rods were found to be the single most important prognostic parameter in this study, with a complete remission (CR) rate of 68% in the Auer-rod-positive and of 40% in the Auer-rod-negative group (p < 0.0001). Survival was significantly longer for patients exhibiting Auer rods (p < 0.0002). Median survival for the total group was 13.5 mo and median remission duration for responders was 11.5 mo in the Auer-rod-positive group compared to 6.2 mo median survival and 9.2 mo median remission duration for the Auer-rod-negative group.

Acute Disease↗
PubMed1979

Framing pictures: the role of knowledge in automatized encoding and memory for gist.

In general, frame theories are theories about the representation and use of knowledge for pattern recognition. In the present article, the general properties of frame theories are discussed with regard to their implications for psychological processes, and an experiment is presented which tests whether this approach yields viable predictions about the manner in which people comprehend and remember pictures of real-world scenes. Normative ratings were used to construct six target pictures, each of which contained both expected and unexpected objects. Eye movements were then recorded as subjects who anticipated a difficult recognition test viewed the targets for 30 sec each. Then, the subjects were asked to discriminate the target pictures from distractors in which either expected or unexpected objects had been changed. One consequence of the embeddedness of frame systems is that global frames may function as "semantic pattern detectors," so that the perceptual knowledge in them could be used for relatively automatic pattern recognition and comprehension. Thus, subjects might be able to identify expected objects by using automatized encoding procedures that operate on global physical features. In contrast, identification of unexpected objects (i.e., objects not represented in the currently active frame) should generally require more analysis of local visual details. These hypotheses were confirmed with the fixation duration data: First fixations to the unexpected objects were approximately twice as long as first fixations to the expected objects. On the recognition test, subjects generally noticed only the changes that had been made to the unexpected objects, despite the fact that the proportions of correct rejections were made conditional on whether the target objects had been fixated. These data are again consistent with the idea that local visual details of objects represented in the frame are not neccesary for identification and are thus not generally encoded. Further, since subjects usually did not notice when expected objects were deleted or replaced with different expected objects, it was concluded that if two events instantiate the same frame, they may often be indistinguishable, as long as any differences between them are represented as arguments in the frame. Thus, for the most part, the only information about an event that is episodically "tagged" is information which distinguishes that particular event from others of the same general class. The data reinforce the utility of a frame theory approach to perception and memory.

Discrimination Learning↗
PubMed1979

Hemiagenesis of the thyroid.

Congenital absence of a lobe of the thyroid gland is discussed and the literature is reviewed. Sixty-six cases have been gathered from the literature in approximately the past 100 years, and another six have been documented. Although no particular explanation has been forthcoming for the development of this anomaly, left lobe aplasia and predominance of occurrence in women have been noted. A variety of other thyroidal abnormalities have coexisted with hemiagenesis.

Adolescent↗
PubMed1979

Effects of thoracic epidural block and the beta-1-adrenoreceptor agonist prenalterol on the cardiovascular response to infrarenal aortic cross-clamping in man.

Sixteen patients scheduled for abdominal aortic resection and grafting were randomly assigned to two groups to study the cardiovascular effects of infrarenal aortic cross-clamping. The patients in the first group had received a thoracic epidural block followed by intravenous administration of the selective beta-1-adrenoreceptor agonist prenalterol prior to induction of general anaesthesia. The patients in the second group served as controls and received no specific treatment prior to general anaesthesia. In both groups, aortic cross-clamping was followed by an equal rise in pulmonary artery diastolic pressure and mean systemic arterial pressure. There was a significant difference in systemic vascular resistance, as the control group had a 46% increase 30 s after cross-clamping, while the pretreated patients had only a 7% increase at the same time. Moreover, the patients given the thoracic epidural block followed by prenalterol increased their stroke volume and cardiac indices, as compared to the patients in the control group who showed a significant decrease in these parameters. Possible mechanisms for the mode of action of the combined thoracic epidural block and beta-1-adrenoreceptor agonist pretreatment are discussed.

Adrenergic beta-Agonists↗
PubMed1979

Deletions, rearrangements and tandem duplications of recombinant plasmids containing yeast ribosomal DNA.

Recombinant DNA plasmids, formed by the insertion of yeast ribosomal DNA into Escherichia coli plasmids pSC101 or pMB9, underwent deletions, rearrangements and tandem duplications. Independently derived deletion products of plasmids, constructed using pMB9 as a vector, are indistinguishable from each other. These deletion products from multimers composed of tandem repeats. In at least one case a plasmid, constructed by inserting an SmaI fragment of yeast ribosomal DNA into pSC101, underwent deletion and rearrangement to form a product in which a segment, consisting of part of the pSC101 sequence and part of the yeast ribosomal DNA sequence, was duplicated to form a tandem repeat. Deletion and rearrangement take place in Rec+, recA- and recB- recC- cells. The rate of deletion in Rec+ cells is higher than in recA- cells. The rate of deletion in minicell-producing, X-ray resistant strains is much higher than in other Rec+ strains.

Chromosome Deletion↗
PubMed1979

Neurological sequelae of septic meningitis. A follow-up study of 65 children.

Seventy-two children who survived septic meningitis were reevaluated after 3 to 11 years. Thirty-four (52%) of 65 children were found to have neurological sequelae. Of the 34, 15 had major sequelae and 19 showed evidence of only minimal brain dysfunction--namely, hyperkinetic behavior, organic learning disturbances and minor motor disabilities. Acute-phase findings that were significantly associated with the rate of neurological sequelae were age, time between onset and admission, seizures, spinal fluid glucose level and the number of polymorphonuclear cells. In view of the high frequency of late neurological sequelae, it is advisable that children who survive septic meningitis have long-term follow-up in order to detect evidence of minimal brain dysfunction. An early diagnosis will help in proper management.

Adolescent↗
PubMed1978

A comparison between spironolactone and hydrochlorothiazide with and without alpha-methyldopa in the treatment of hypertension.

In a single blind crossover trial, spironolactone (50 mg twice a day), and hydrochlorothiazide (50 mg twice a day) were equally effective hypotensive agents in 16 patients with untreated essential hypertension. The addition of alpha-methyldopa (250 mg three times a day) to each agent produced a further significant and equal fall in blood pressure. Spironolactone therapy was assoicated with fewer clinical and biochemical side effects. The hypotensive effect of the diuretics was independent of the renin status of the patients.

Adult↗