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Biomedical subjects

S A Pedersen

Publications and source records attributed to S A Pedersen.

At least 109 records · Page 6Linked to original sources
PubMed1983

Suppression of B lymphocytes in mature newborn infants.

The ability of cord blood lymphocytes to secrete immunoglobulins during in vitro culture was investigated by means of a reverse hemolytic plaque forming cell (PFC) assay. Mononuclear cord blood cells did not differentiate into immunoglobulin-secreting cells after stimulation with the polyclonal B lymphocyte activator pokeweed mitogen (PWM), contrary to the findings in normal adults. Mononuclear cord blood cells were then separated into T-enriched and T-depleted blood lymphocyte subsets. When these were co-cultured, the PWM-induced immunoglobulin secretion was still low; following irradiation of the T-enriched cells, the numbers of IgM-PFC but not of IgG- or IgA-PFC increased considerably. The effect of irradiation of the T-enriched cells on the PWM-induced IgM response was dose-dependent, with maximal effect at 2500 rad. It is concluded that the low PWM responses obtained using cord blood lymphocytes are in part due to suppression by radiosensitive T suppressor cells. Following removal of this suppression by means of irradiation, B lymphocytes can be induced to secrete IgM, but not IgG or IgA.

Adult↗
PubMed1982

Plasma noradrenaline and adrenaline in infants of diabetic mothers at birth and at two hours of age.

Plasma noradrenaline and adrenaline in the umbilical artery were very high in many infants of both diabetic mothers (IDM) and non-diabetic mothers (controls) compared to values obtained in adults. Blood pH was slightly but significantly lower in IDM than in controls at delivery. There was a significant negative correlation between plasma noradrenaline and blood pH in IDM at birth, but no correlation between plasma noradrenaline and blood glucose, birth weight and Apgar scores. Plasma noradrenaline decreased significantly from birth to two hours of age both in IDM and controls. At two hours of age plasma noradrenaline and adrenaline were significantly greater in IDM compared to controls whereas blood glucose concentration was lower in the former group. There was a close inverse correlation between plasma noradrenaline and adrenaline, respectively, and blood glucose in IDM at two hours of age but not in controls. The elevated plasma noradrenaline at delivery in IDM may be explained by clinically undetectable acidosis whereas elevated plasma catecholamines at two hours are probably due to hypoglycaemia.

Blood Glucose↗
PubMed1981

Scintigraphy with 99mTc-(2,6-diethylacetanilide)-iminodiacetic acid as a diagnostic test in traumatic lesions of the liver and biliary tract.

99mTc-HIDA scintigraphy was used as a diagnostic procedure in three patients with liver and biliary tract injuries following blunt abdominal trauma. The scintigraphic characteristics are illustrated and discussed. The application of this method is recommended in patients who are clinically stable and in whom the physical findings are equivocal. Furthermore, important information can be gained in patients who have an unsatisfactory course after operative treatment of liver and biliary tract injuries.

Biliary Tract↗
PubMed1981

The use of [99mTc](2,6-diethylacetanilide)-iminodiacetic acid ([99mTc]HIDA) in evaluating normal hepatobiliary dynamics.

Scintigraphic examination with [99mTc]HIDA was used to investigate fasting hepatobiliary dynamics in thirty normal subjects, fifteen males and fifteen females. Ten were studied in duplicate. All subjects visualized the bile ducts and showed gallbladder filling within 60 min. All but three demonstrated excretion of bile to the duodenum. Only five subjects showed activity in the gut before gallbladder visualization. Twenty-one had one or more contractions of the gallbladder. A significant positive correlation was found between age and excretory liver function in males, signifying a lower excretory capability with advancing age. The median percentage deviation for gallbladder and gut visualization in repeat tests was 40% and 88%, respectively. It is concluded that the hepatic bile in the fasting state is delivered to the gallbladder as well as to the duodenum. Furthermore, the results suggest a cyclic function of the biliary tract based upon coordination between the gallbladder and the sphincter of Oddi.

Adult↗
PubMed1981

Scintigraphic investigation of bilio-intestinal anastomoses using 99mTc-(2,6-diethylacetanilide)-iminodiacetic acid (99Tc-HIDA).

Hepatobiliary scintigraphy was performed in 30 normals and 22 patients who had a bilio-intestinal anastomosis. The patient group included 12 without symptoms and 10 with upper abdominal symptoms. All the anastomoses studied were visualized and persisting dilatation of the bile ducts was recognized in 10/12 and 7/10, respectively. Mean time for bile duct and gut visualization was significantly lower in normals as compared with both patient groups. There were no differences of any statistical significance between the two patient groups. One patient with clinical suspicion of bile leakage from the anastomosis was confirmed. Patients with stricture of the anastomosis did not have characteristics which would distinguish them from patients in well-being. It is concluded that 99mTc-HIDA scintigraphy has a low sensitivity when used to disclose the causes of symptom giving malfunction of bilio-intestinal anastomoses. The exception to this is patients with bile leakage into the peritoneal cavity, in whom scintigraphy is the only non-invasive method which can reveal the condition.

Adult↗
PubMed1979

Hepatobiliary scintigraphy with 99Tcm-HIDA in patients with jaundice.

In order to assess the clinical value of 99Tcm-HIDA for hepatobiliary scintigraphy 23 patients with hepatocellular disease and 44 patients with obstructive biliary tract disease were examined. Positive information was obtained in 14 and 23 patients, respectively. False results mainly depended on inadequate imaging of the liver in the case of severely impaired function, whatever the cause. Spontaneously ameliorated obstruction leaving an impaired hepatocellular function may give misleading results. A malignant tumour widely involving the liver and impressing the bile ducts may also create the appearance of obstruction. If HIDA scintigraphy be limited to patients with serum bilirubin levels between 40 and 250 mumol/l the diagnostic specificity and sensitivity of 90 per cent and 78 per cent, respectively, is reached in demonstrating obstruction, when the prevalence is 0.58.

Adult↗