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T Nørgaard

Publications and source records attributed to T Nørgaard.

36 records · Page 2Linked to original sources
PubMed1986

The differential diagnosis of intraepidermal malignant lesions using immunohistochemistry.

The malignant intraepithelial proliferations--malignant melanoma level I, bowenoid epithelial dysplasia, and mammary as well as extramammary Paget's disease--may cause differential diagnostic difficulties. We have examined 12 cases of malignant melanoma level I, nine cases of bowenoid epithelial dysplasia, 17 cases of extramammary and five cases of mammary Paget's disease for S100 protein, carcinoembryonic antigen (CEA), cytokeratin, and keratin to evaluate the sensitivity and specificity of these reactions with regard to their differential diagnostic value. Antibodies against S100 reacted specifically with the tumor cells in intraepithelial malignant melanomas; antibodies against CEA reacted specifically with the tumor cells in Paget's disease; and cytokeratin and keratin antibodies reacted with the epithelial tumor cells in Paget's disease as well as in bowenoid epithelial dysplasia. However, only antibodies to CEA and keratin showed 100% sensitivity. We conclude that the investigated antibodies may be of differential diagnostic value in cases of intraepidermal neoplasias, but that a negative reaction does not exclude diagnosis of these diseases.

Bowen's Disease↗
PubMed1986

The regulation of subcutaneous blood flow in patient with Dercum's disease.

Dercum's disease or adiposis dolorosa is a poorly understood disorder with painful fatty deposits in the skin localized to the lower extremities. The etiology is unknown. In such a patient the mechanisms of local regulation of blood flow in subcutaneous tissue was investigated by the local 133Xenon washout technique. The patient was reinvestigated one week after treatment with intravenous lidocaine. The local vasoconstrictor response to increase in venous transmural pressure was not present in this patient, but reappeared after lidocaine treatment. Autoregulation of blood flow in subcutaneous tissue was present before as well as after lidocaine treatment. It seems likely that a pain elicited increase in sympathetic activity in the vasoconstrictor fibres abolished the normal vasoconstrictor response to increase in venous transmural pressure. The mechanism of pain relief after intravenous lidocaine infusion is uncertain, but central as well as peripheral mechanisms may be considered.

Adiposis Dolorosa↗
PubMed1985

Impaired autoregulation of blood flow in subcutaneous tissue of long-term type 1 (insulin-dependent) diabetic patients with microangiopathy: an index of arteriolar dysfunction.

Autoregulation of blood flow in subcutaneous tissue was studied at the level of the lateral malleolus in eight long-term Type 1 (insulin-dependent) diabetic patients with clinical microangiopathy, eight short-term Type 1 diabetic patients without clinical microangiopathy and seven healthy control subjects. Blood flow was measured by the local 133Xenon washout technique. Mean arterial blood pressure was reduced by a maximum of 23 mmHg by elevating the limb above heart level and elevating to a maximum of 70 mmHg by head-up tilt; in the latter position venous pressure was kept constant and low by activation of the leg muscle vein pump (heel raising). Mean arterial blood pressure was thus varied between 60 and 160 mmHg. In normal and short-term diabetic subjects blood flow remained within 10% of control values during the changes in arterial blood pressure. In six of the eight Type 1 diabetic patients with clinical microangiopathy, autoregulation of blood flow was impaired, blood flow changing approximately 20% per 10 mmHg change in arterial blood pressure; the slope of the autoregulation curves was significantly higher compared with the two control groups (p less than 0.02). Resting mean arterial blood pressure was significantly elevated in long-term diabetic patients (median: 107 mmHg) compared with short-term diabetic (median: 85 mmHg) and control subjects (median: 91 mmHg) (p less than 0.01 and p less than 0.02, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Endocrine liver tumour differential diagnosis from hepatocellular carcinoma.

A liver tumour, initially diagnosed by light microscopy as a hepatocellular carcinoma, was later shown to be endocrine by argyrophilia and electron microscopy. It was tested by immunohistochemistry for insulin, glucagon, gastrin, VIP, pancreatic polypeptide, glicentin, C-peptide and somatostatin. A few cells were shown to contain somatostatin, but the secretion product in most of the cells was not identified. The patient is well, without any sign of endocrine disturbances, 18 months after the operation.

Carcinoma, Hepatocellular↗
PubMed1985

Correlation between distal nephron enzyme activity, structure and function in rats during lithium and lithium plus neuroleptic treatment.

The histochemical activities of nonspecific acid and alkaline phosphatases, NADH- and NADPH-tetrazolium reductases, alpha-glycerophosphate dehydrogenase, succinate dehydrogenase, isocitrate dehydrogenase, lactate dehydrogenase and glucose-6-phosphate dehydrogenase were investigated in kidneys from rats treated with lithium and lithium plus neuroleptics. During the first 8 weeks of lithium treatment the activity of NADH-tetrazolium reductase, succinate dehydrogenase and alpha-glycerophosphate dehydrogenase activity in the collecting ducts increased. The other enzymes did not change. After 8 weeks of treatment no further changes in enzyme activity occurred. Withdrawal of lithium caused normalization of enzyme activity after 8 weeks. A decrease in concentration ability was found in parallel with the increase in enzyme activities (p less than 0.001). The changes in enzyme activity were not significantly correlated to morphological changes in the collecting ducts. Treatment with neuroleptics alone caused no change in enzyme activity. During combined lithium plus neuroleptic treatment the enzyme activities changed in a similar way as during lithium therapy, but the changes were less pronounced. In parallel, a less pronounced decrease in concentration ability was found during this treatment.

Animals↗
PubMed1984

The effect of Tween 20 on indirect immunoperoxidase staining of blood group antigen A in human urothelium.

The effect of the nonionic detergent Tween 20 on background staining, sensitivity, and specificity in the indirect immunoperoxidase staining for blood group antigen A was investigated histologically and spectrophotometrically. Pretreatment of dewaxed formalin-fixed Paraplast-embedded tissue sections from human ureters with 2% Tween 20 and dilution of the first and second layer antisera with 0.05 or 2% Tween 20 significantly reduced background staining of the urothelial cell cytoplasm, ureteral stroma, and musculature. Spectrophotometrical analysis of tissue sections from hypernephroma (rich in cytoplasm), cervix (fibrous stroma), and myometrium (musculature) underlined the histological results with a significant reduction of the maximum absorbance of Tween 20-modified indirect immunoperoxidase-stained tissue sections. Sensitivity, evaluated histologically by the endpoint titers of urothelial cell membrane staining, endothelial cell staining, and focal cytoplasmic staining of urothelial cells, was not influenced by the Tween 20 treatment. The specificity was improved as the staining was highly reduced or absent in control sections subjected to Tween 20.

ABO Blood-Group System↗
PubMed1982

The ultrastructure of the macula densa during altered sodium intake. A morphometric study of the macula densa in the rabbit nephron.

Cells of the macula densa from sodium-depleted, sodium-loaded and normal rabbit kidneys were investigated morphometrically by light and electron microscopy. The total macula densa volume constituted 0.14 per cent of the cortical volume and was unchanged during altered sodium balance. Ultrastructurally the macula densa cells appeared similar at the three different levels of sodium intake investigated. However, the relative volume of Golgi apparatus in the cells of the macula densa decreased from the normal value of 1.54 per cent of the cytoplasmic volume to 1.25 per cent during sodium-load, indicating that functional changes take place in the cells of the macula densa under these conditions. The volume of the Golgi apparatus was unchanged in the sodium-depleted group. The volume of the cytoplasm, the nuclei and the intercellular space which normally constitute 56 per cent, 28 per cent and 15 per cent of the total volume of the macula densa, respectively, were unchanged during sodium-load and sodium-depletion. The mitochondria which normally constitute 25 per cent of the cytoplasmic volume were similarly unchanged.

Animals↗
PubMed1981

Functional and structural rat kidney changes caused by peroral or parenteral lithium treatment.

Renal functional and structural changes were studied in rats treated with lithium for 5 months. The lithium was administered in two different ways: in the food or as a daily intraperitoneal injection. In the perorally treated rats serum lithium was relatively constant during the day. In the injected rats serum lithium reached a high peak value just after the injection followed by a decrease to very low values. In all rats an increased water consumption and a reduced renal concentration ability were seen during lithium treatment. Light microscopy showed focal degenerative changes in the distal convoluted tubule and collecting ducts. These changes comprised nuclear and cellular polymorphism and tubular dilatation. The functional as well as the structural changes were most pronounced in the rats treated with peroral lithium, and a correlation between the functional and morphological changes was present. It is concluded that lithium is more harmful to the kidney when the administrations give a relatively constant serum lithium level, such as in peroral administration, than when administration causes great variations, including peak values and very low minimum levels in serum lithium. The reason for this might be that a number of regenerative processes occur only in periods with low lithium concentrations.

Administration, Oral↗
PubMed1980

Quantitation of glucose-6-phosphate dehydrogenase activity in cortical fractions of the nephron in sodium-depleted and sodium-loaded rabbits.

Glucose-6-phosphate dehydrogenase activity was measured quantitatively in isolated cortical fractions of the nephron in sodium-depleted and sodium-loaded rabbits. The samples consisted of isolated fractions of macula densa, proximal convoluted tubule, distal convoluted tubule and glomerulus. In sodium-depleted rabbits enzyme activity was identical to that of normal rabbits. In sodium-loaded rabbits a significant decrease in enzyme activity was found in the macula densa and proximal convoluted tubule. However, using conventional histochemical incubation methods semiquantitative estimation of glucose-6-phosphate dehydrogenase showed a slight decrease in enzyme activity in the macula densa and distal convoluted tubule, and a slight increase in the proximal convoluted tubule during sodium-depletion. During sodium-load a pronounced decrease in enzyme activity was seen in the macula densa and distal convoluted tubule. These results show that semiquantitative histochemical evaluation of changes in enzyme activity is less reliable than the more precise quantitative method especially when there are only slight changes in enzyme activity. Only where there were marked changes in histochemical enzyme activity might the results of quantitative and semiquantitative methods be in accord.

Animals↗
PubMed1979

Quantitative measurement of glucose-6-phosphate dehydrogenase in cortical fractions of the rabbit nephron.

A quantitative fluorimetric method is described for estimating the activity of glucose-6-phosphate dehydrogenase in isolated fractions of rabbit nephron from the superficial part of the renal cortex: macula densa, proximal convoluted tubule, distal convoluted tubule and glomerulus. The mean activity in the macula densa region was 2.5 X 10(-18) mol/micrometers 3/min, which was about twice the mean activity of the proximal and distal tubular cells and four times that of the glomeruli. As glucose-6-phosphate dehydrogenase is located in the cytoplasm, the average cytoplasmic enzyme activity of the different tubular cells was calculated: macula densa activity was 4.0 X 10(-18) mol/micrometers 3/min whilst proximal tubular cells showed about a third, and distal tubular cells about a quarter of this activity.

Animals↗
PubMed1978

Structural changes in kidneys of patients with oliguric extracapillary glomerulonephritis during immunosuppressive therapy.

Structural changes in kidney biopsies were investigated from five patients with primary oliguric extracapillary glomerulonephritis in whom the renal function was adequately maintained during extended combined immunosuppressive treatment. The most important structural change was a pronounced decrease in the number of crescents. Reduction in numbers of crescents in the late biopsies was significantly greater than the increase in the number of hyalinized glomeruli. Tubular parenchyma showed only slight diffuse atrophy, and a moderate interstitial fibrosis was always present during the latter stages of treatment. Disappearance of crescents in the glomeruli was not accompanied by disappearance of immunoglobulins. Successfull immunosuppressive treatment of extracapillary glomerulonephritis causes the disappearance of structural characteristics of the kidney that are diagnostic for this disease.

Adult↗
PubMed1978

Histochemical enzyme activity correlated to the structural segmentation of the proximal convoluted tubule in salt-depleted and salt-loaded rat kidneys.

In salt-depleted and salt-loaded rat kidneys a study was made of the structural segmentation of the proximal convoluted tubule (PCT) and the histochemical activity of non-specific acid and alkaline phosphatases and succinate dehydrogenase in the same segments. No quantitative structural or segmental alterations were observed, but significant changes in enzyme activity occured. These comprised: 1) A decrease in activity of acid phosphatase in segment 1 and the transitional zone in salt-depleted kidneys, and an increase in enzyme activity in segment 2 in salt-loaded kidneys. 2) a decrease in alkaline phosphatase activity in segment 2 in both salt-depleted and salt-loaded kidneys and 3) a decrease in succinate dehydrogenase activity in segment 2 in salt-depleted kidneys, and an increase in activity in the same segment in salt-loaded kidneys. Thus long-term variation in sodium intake are followed by segment-correlated variations in the activity of acid and alkaline phosphatase and succinate dehydrogenase in the PCT.

Acid Phosphatase↗
PubMed1978

Volume changes in the rat renal cortex during urography.

At different periods of urography rat kidney were instantly frozen at -165 degrees C. Using appropriate histological techniques and planimetry of different cortical compartments and fractions the structural background of renal cortical volume variations during urography was elucidated. The renal cortex reacted to intravenous injection of hypertonic contrast medium with an immediate increase of volume, followed by a decrease from 30 to 60 seconds. Measuring the volume shares of different cortical compartments, the complex nature of cortical volume variations during the first minutes of urography could be demonstrated. Subdivision of the tubular compartments into cellular and luminal fractions showed even greater complexity of volume variations. All the major cortical volume changes came to an end approximately three minutes after the injections.

Animals↗
PubMedDate not supplied

Effect of strict metabolic control on regulation of subcutaneous blood flow in insulin-dependent diabetic patients.

The effect of 10 weeks of improved metabolic control on the impaired autoregulation of the subcutaneous blood flow was studied at the level of the lateral malleolus in eight long-term insulin-dependent diabetic patients with clinical microangiopathy. Blood flow was measured by the local 133-Xenon washout technique. Mean arterial blood pressure was reduced by a maximum of 23 mmHg by elevating the limb above heart level and elevated to a maximum of 65 mmHg by head-up tilt; in the latter position venous pressure was kept constantly low by activation of the leg muscle vein pump (heel raising). Improved metabolic control was achieved using either continuous subcutaneous insulin infusion or multiple insulin injections. The blood glucose concentration declined from (median) 12.7 to 6.8 mmol/l and the HbA1C level from 10.1 to 7.5% during strict metabolic control (p less than 0.01 and p less than 0.01, respectively). The slope of the subcutaneous blood flow autoregulation curves during poor metabolic control (median: 11.6% per 10 mmHg, range: 8.0-30.5% per 10 mmHg) was not significantly different from the slope values during improved metabolic control (13.4% per mmHg, 10.1-24.4% per mmHG). No association was demonstrated between the impaired autoregulation of subcutaneous blood flow and the metabolic parameters. Our results indicate that improved metabolic control for 10 weeks has no effect on the impaired autoregulation of subcutaneous blood flow in long-term insulin-dependent diabetic patients with clinical microangiopathy.

Adult↗
PubMedDate not supplied

Nocturnal subcutaneous hyperaemia in the lower leg and foot of type 1 diabetic patients.

Nocturnal fluctuations in subcutaneous blood flow in the lower leg and foot were measured during sleep in Type 1 diabetic patients without autonomic neuropathy. Subcutaneous blood flow was measured, simultaneously, 100 mm above the malleolus on the medial aspect of the right lower leg and at the dorsum of the left foot in 10 diabetic patients, and on the right lower leg only in 10 normal human subjects over 12-20 h. The 133Xe wash-out technique, portable CdTe (Cl) detectors and a portable data storage unit were used. The tracer depots were applied by means of the epicutaneous, atraumatic labelling technique. In diabetic patients, subcutaneous blood flow increased 102 +/- 68% in the lower leg and 111 +/- 98% in the foot at 113 +/- 32 min and 107 +/- 37 min, after going to sleep. The hyperaemic phase lasted 128 +/- 43 min and 150 +/- 42 min, respectively. The hyperaemic response was not different from that in the control subjects (89 +/- 61%). There was no significant correlation between the absolute hyperaemia in the leg and that in the foot. In conclusion, Type 1 diabetic patients without autonomic neuropathy have normal nocturnal hyperaemia during sleep.

Adipose Tissue↗