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Biomedical subjects

R Arnold

Publications and source records attributed to R Arnold.

At least 523 records · Page 29Linked to original sources
PubMed1981

Risk factors for infections of the oropharynx and the respiratory tract in patients with acute leukemia.

The pathogenicity of microorganisms isolated by surveillance cultures, the neutrophil count in the peripheral blood, and the interaction of the two factors were analyzed as risk factors for infections of the oropharynx and the respiratory tract in patients with acute leukemia being treated in strict reverse isolation under antimicrobial modulation. A statistical method was developed for the identification of bacteria, the presence of which was correlated with an increased risk of infection. A significantly increased risk was found mainly for species of Klebsiella, Enterobacter, Proteus, and Pseudomonas. The degree of neutropenia was significantly correlated with the risk of infection, which was influenced by the microbiologic state of the oropharynx. Thus, patients with gram negative bacilli had significantly more days with infection at all levels of neutropenia than patients without gram-negative bacilli. These two risks factors were additive but did not potentiate each other.

Acute Disease↗
PubMed1981

Limited value of in vitro techniques for the detection of leukocyte alloantibodies during granulocyte transfusion therapy.

A 23-year-old male patient undergoing first induction chemotherapy for acute myeloid leukaemia received granulocyte transfusions on 10 consecutive days. An average of 2.1 X 10(10) granulocytes was given per square metre body surface area per day. Transfusion reactions and absence of post-transfusion granulocyte increment after the fifth granulocyte transfusion suggested the presence of leukocyte antibodies. However, no antibodies were detectable at this time by the lymphocytotoxicity test, the indirect granulocyte immunofluorescence test, or the platelet suspension immunofluorescence test. In contrast to the clinical observation, the serological detection of leukocyte antibodies was only possible 1 day after the last granulocyte transfusion.

Adult↗
PubMed1981

In vitro and in vivo studies on filter collected granulocytes.

The in vitro function of granulocytes collected by filtration leukapheresis after premedication of donors with dexamethasone was found to be normal. In vivo studies were performed in a 21-year-old woman who was transplanted with allogeneic bone marrow for severe aplastic anaemia. The patient received granulocyte transfusions for treatment of septicaemia during the transplantation period. On 11 consecutive days an average dose of 7.2 X 10(10) granulocytes/transplantation, the patient died from cardiac failure. Transfused granulocytes were found ante mortem in a pericardial effusion and post mortem in lungs, kidneys, liver and spleen. The data indicate that filter collected granulocytes function normally in the recipient and are clinically effective.

Adult↗
PubMed1981

Granulocyte transfusions in acute leukaemia. Regeneration of granulopoiesis as determining factor of survival.

40 patients with acute leukaemia and severe granulocytopenia were treated with granulocyte transfusions for bacteriologically documented or clinically suspected septicaemia. The patients received an average of 5 transfusions each with 2.1 X 10(10) granulocytes per m2 body surface area per day. 26 patients showed clinical benefit from transfusion therapy as documented by the course of blood cultures, local lesions and fever. Only patients with regeneration of granulopoiesis had definite benefit from granulocyte transfusions. All other patients died ultimately from septicaemia.

Acute Disease↗
PubMed1981

Inhibition of dental plaque acid production by the salivary lactoperoxidase antimicrobial system.

Resting human whole saliva inhibited acid production by glucose-stimulated, homologous plaque. The degree of inhibition of plaque acid production correlated positively with the concentration of hypothiocyanite (OSCN-) ions in saliva. Supplementation of saliva with an appropriate combination of thiocyanate and hydrogen peroxide resulted in a significant increase in the concentration of OSCN- ions and in more effective inhibition of plaque acid production. In most cases, the inhibition was complete when the supplements were added directly to saliva-plaque mixtures. Acid production resumed when the inhibitory effect of OSCN- was reversed by addition of thiols. Among the oral defense factors, the salivary lactoperoxidase system seems to play an important role by producing highly reactive antibacterial products (including OSCN-) which can regulate bacterial metabolism in the human mouth. The concentration of OSCN- in normal human whole saliva seems to be just below the threshold level required for plaque inhibition. Therefore, enhancement of this system in vivo may be effective in the regulation of plaque acid production.

Animals↗
PubMed1981

Ventricular septal defect in children born in Liverpool 1960 to 1969. Evaluation of natural course and surgical implications in an unselected population.

We have reviewed data on all patients born between 1960 and 1969 and registered in the Liverpool Registry of Congenital Malformations as having congenital heart disease. There were 385 with a ventricular septal defect as their sole or main cardiac lesion. Analysis of the available follow-up data showed that 50 of these were subsequently assigned in other diagnostic categories and a further 41 failed to fulfil our diagnostic criteria for a ventricular septal defect, leaving 294 patients for study. In view of the high incidence of small defects in asymptomatic infants and children not subjected to cardiac catheterisation, clinical criteria for the acceptance of the diagnosis were defined and 190 patients were included on these grounds alone. The clinical course, associated cardiac and non-cardiac defects, and surgical implications were analysed. The majority of defects were small and 31% closed spontaneously. Fifty per cent of the deaths in infancy were unrelated to the ventricular septal defect. We estimate that by present criteria only 15% of an unselected population of patients with a ventricular septal defect are likely to require surgical treatment.

Child↗
PubMed1981

Congenital heart disease among 160 480 liveborn children in Liverpool 1960 to 1969. Implications for surgical treatment.

Among 160 480 children born alive between 1960 and 1969 in Liverpool, 884 patients with structural congenital heart disease were identified. Data on these patients have been reviewed in order to estimate the number likely to need cardiac surgery during childhood and adolescence. Though only 33.9% of patients had surgery, we estimate that if current policies for management were followed, 475 (53.7%) patients would not require surgery. Extrapolation of this data suggests that each year in England and Wales approximately 830 infants (1383 per million livebirths) will require cardiac surgery within the first year of life and a further 1424 operations (2374 per million livebirths) will be required in later childhood or adolescence. No attempt has been made to estimate the number of operations for congenital heart disease which may prove necessary in adult life.

Adolescent↗
PubMed1981

Somatostatin and gastrin release into the gastric lumen in rats.

Somatostatin and gastrin release into the gastric lumen was investigated in anaesthetized, vagally intact rats. The stomach was perfused at a flow rate of 0.5 mL.min-1. During perfusion with 0.1 M HCl or buffers of varying pH the somatostatin ans gastrin concentrations in the perfusate were less than 10 pg.mL -1 and approximately 30 pg.mL-1, respectively. Peptone caused a gastrin concentrations in the perfusate were less than 10 pg.mL-1 and approximately 30 pg.mL-1, respectively. Peptone caused a slight pH-independent increase in somatostatin release; gastrin release was unchanged despite an increase in serum gastrin from a basal of 15 +/- 4 to 155 +/- 34 pg.mL-1 during peptone stimulation. intravenous infusion of carbachol (1 microgram.kg-1.min-1) strongly stimulated luminal somatostatin and gastrin release (from 5 +/- 1 to 192 +/- 52 pg.mL-1 and from 27 +/- 5 to 198 +/- 41 pg.mL-1, respectively) during perfusion with 0.1 M HCl. Phosphate buffer perfusion at pH 7.5 abolished the cholinergic-mediated somatostatin release but the gastrin response was unaffected. It is suggested that changes of luminal hormone concentrations in the rat stomach do not reflect the secretory activity of the endocrine cells in the gastric mucosa.

Animals↗
PubMed1981

Appraisal of the Mustard procedure for the physiological correction of "simple" transposition of the great arteries. Eighty consecutive cases, 1970-1980.

Eighty successive patients underwent the Mustard operation for "simple" transposition of the great arteries (TGA) between January, 1970, and January, 1980. Ages ranged from 42 days to 12.4 years (mean 14.7 months). Balloon atrial septostomy (BAS) with balloon volumes of more than 2.5 ml produced significant increases of arterial oxygen saturation, although the initial benefit of BAS was greater than that found at follow-up catheterization. In these patients the left ventricular (LV) pressure tended to decrease during the first months of life, but this drop was less marked at the end of the first year. Deep hypothermia and cardiocirculatory arrest were employed in all cases. Several modifications were adapted to the original surgical technique in order to reduce last sequelae. There were two early and three late deaths. At follow-up (mean 4.5 years) 74% of patients were symptom free. Sinoatrial and atrioventricular (AV) conduction disturbances were present in five and six patients, respectively. Caval or pulmonary venous obstruction occurred in 13 patients, seven of whom required reoperation. Isolated tricuspid valve incompetence was present in one patient only, but in four it was associated with other defects. Primary right ventricular (RV) failure occurred in one patient. These findings, in relation to mortality, complications, and the excellent clinical results in the majority of survivors, compare favorably with results published for patients with "simple" TGA who have been subjected to other types of physiological or anatomic correction. At the present time, there seems to be no good reason to alter our surgical policy in this group of patients.

Blood Pressure↗
PubMed1980

Lymphocytotoxic antibodies in patients receiving granulocyte transfusions.

The presence of lymphocytotoxic antibodies was studied in 22 patients receiving granulocyte transfusions. Due to previous blood transfusions 7 out of 22 patients had lymphocytotoxic antibodies before granulocyte transfusions were started. 6 out of 15 unsensitized patients developed antibodies during granulocyte transfusion therapy, and 9 out of 15 patients had no detectable antibodies at any time. Transfusion reactions occurred in the presence of lymphocytotoxic antibodies not directed against donor cells.

Adolescent↗
PubMed1980

Trypsin radioimmunoassay in the diagnosis of chronic pancreatitis.

Serum immunoreactive trypsin (IRT) determination has been recommended as a screening test in chronic pancreatitis. Using a commercial radioimmunoassay kit (RIA--gnost Trypsin; Behring-Werke, Marburg/Lahn, FRG) the interassay coefficient of variation was 26--44% for three different test sera. Gel filtration chromatography profiles revealed immunoreactivity in the position of 125I-trypsin and (less than 50%) in the void volume. The test was evaluated in controls (n = 90), chronic relapsing pancreatitis (CRP;n = 60) and after total pancreatectomy (n = 5). In 65% of the CRP cases decreased IRT values were found, whereas during acute attacks of CRP supranormal and normal values were found. After total pancreatectomy IRT levels were undetectable. It is concluded that the sensitivity of this IRT test is limited and that the available test system needs improvement.

Cholecystokinin↗
PubMed1980

Plasma-immunoreactive trypsin in chronic renal failure.

Plasma-immunoreactive trypsin (IRT) was measured by radioimmunoassay in 52 patients with chronic renal failure. 29 were on conservative treatment, 14 on-regular haemodialysis, and 9 on regular haemofiltration. IRT levels were elevated in those with raised plasma creatinine and there was a significant positive correlation to plasma creatinine concentrations (r = 0.853; p less than 0.001). IRT levels were not significantly altered by haemodialysis or haemofiltration. It is concluded that the kidney plays an important role in the metabolism of plasma trypsin. Since plasma IRT levels may be elevated in patients with chronic renal failure, the IRT determination may be misleading in diagnosing acute and chronic pancreatitis in the presence of kidney disease.

Creatinine↗