Biomedical subjects
P Drouin
Publications and source records attributed to P Drouin.
Cytologic follow-up of patients with invasive cervical carcinoma treated by radiotherapy.
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Growth hormone responses to the stimulation of hypothalamic glucoreceptors in diabetic retinopathy. Effects of catecholamine precursors and dopamine antagonists.
The effects of the stimulation of glucoreceptors located at the level of the lateral hypothalamic nuclei and sensitive to intracellular glucose deprivation on growth (GH) release are well documented in the monkey. In this study the effect of a reproducible hypoglycemic stimulatory procedure was controlled by continuously monitoring blood glucose (BG) levels in normal subjects and in a series of 120 diabetic patients. In contrast to control subjects, GH responses to similar hypoglycemic nadirs were not reproducible in diabetics (with or without diabetic retinopathy). The infusion of levodopa, precursor of both norepinephrine (NE) and dopamine, during BG decline rendered the GH response to hypoglycemia consistently reproducible. To investigate the site of action of levodopa, a group of diabetics were pretreated with a centrally active dopamine antagonist, metoclopramide hydrochloride. The pattern of GH release was similar in both groups. These data suggest that in diabetes the interaction of levodopa and adequate stimulation of hypothalamic glucoreceptor systems is mediated by an NE transmission.
[Changes of beta-thromboglobulin levels in diabetic patients controlled with the artificial pancreas].
beta-Thromboglobulin (beta-TG), which is a specific platelet protein, is considered to be a fair indication of in vivo platelet activation. Our investigation was aimed at testing the influence of the glucose balance on platelet behaviour by measuring beta-TG levels in insulin-dependent diabetic patients subjected to blood feed-back control via an artificial pancreas over a 24 or 48 hour period. In 19 patients who underwent feed-back control over a 24 hour period, no significant change in beta-TG level was observed on average, compared with the measurements carried out before blood glucose control. In contrast, in the 11 diabetic patients treated over a 48 hour period, this plasma level decreases slightly but significantly compared with the levels observed before glycemia regulation (55.6 +/- 26.6 ng/ml vs. 74.2 +/- 24.9 ng/ml). We were unable to find any correlation in these patients between the beta-TG levels measured at each of the three sampling periods and the blood glucose level-measured simultaneously or continuously-or the glycosylated hemoglobin level measured at the beginning of the study. These results suggest that, in spite of the lag phase, blood glucose control has a beneficial influence on the platelet hyperactivity and therefore a poor glycemia regulation could be largely responsible of this disorder. However, in view of the persistence of abnormally high plasma beta-TG level after 48 hours, we are led to believe that strict blood glucose control has not been sufficiently prolonged.
[Influence of metabolic control on blood viscosity and platelet activity in insulin requiring diabetics].
Blood and plasma viscosities were determined using respectively a Couette type micro-viscometer (LS 30) and an automatic capillary viscometer (FICA). Plasma beta-thromboglobulin (beta-TG) levels were determined by radioimmunoassay. These parameters were measured in a group of 11 poorly controlled insulin requiring diabetics before and after blood glucose normalization using an artificial pancreas (Biostator GCIIS). Before connection to the artificial pancreas, blood and plasma viscosity and beta-TG levels were significantly higher in diabetics than in controls. The strict metabolic control obtained by the artificial pancreas resulted in a normalization of the hemorheological parameters and in a significant reduction of plasma beta-TG levels after 48 h. These results suggest that the metabolic control of diabetes influences the rheological behavior of blood and the metabolism of platelets.
[Metabolism of insulin and immunoreactive insulin-like substances (proinsulin, HWIRI) in vivo in man].
Immunoreactive insulin (IRI) and its three constituents as determined by gel filtration: high molecular weight substances with insulin immunoreactivity (HWIRI), proinsulin (PI) and insulin (I), were measured hourly during 28 hours in the portal, hepatic and peripheral venous systems of a patient operated for a nesidioblastoma. The PI levels were constant from one system to the other (7.1 +/- 0.8 microU/ml; 7.3 +/- 0.8 microU/ml; 9.2 +/- 1.2 microU/ml). The I levels decreased from the portal (53.3 +/- 5.2 microU/ml) to the hepatic venous system (28.0 +/- 1.0 microU/ml) and from the latter to the peripheral venous system (19.8 +/- 2.0 microU/ml). The HWIRI levels were stable between the portal and the hepatic venous systems (4.7 +/- 0.7 microU/ml; 4.8 +/- 0.6 microU/ml) and higher in the peripheral system (8.2 +/- 1.2 microU/ml). Our results demonstrate that: --I is essentially degraded by the liver. --There is no variation of PI in the three compartments. --HWIRI is formed in the circulation. --Variations of IRI levels between venous systems acquire physiological significance only when accompanied by the variations of the levels of each constituent.
Hyperinsulinemia associated with normal C-peptide levels in a woman treated with isoniazide.
The authors report on the observation of a woman treated with isoniazide, who presented clinical symptoms of hypoglycemia during treatment (seating, confusion, anxio-depressive syndrome, lipothymia). After the antitubercular treatment was stopped, a moderate hypoglycemia without clinical manifestations accompanied by a marked hyperinsulinemia and normal C-peptide values was detected during a Conn's test. Serum gel filtration on Sephadex G 50 Fine showed that the measured hyperinsulinemia was effectively due to an insulin excess. This excess did not seem caused by surreptitious insulin injection. This seems to be the consequence of a deficiency in insulin catabolism because the C-peptide level was normal. The possible role of isoniazide on carbohydrate metabolism is discussed.
[Incidence of various angiographic symptoms of diabetic retinopathy].
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[Xerographic measure of Achilles tendon thickness in familial hypercholesterolemia].
The authors have applied a xeroradiographic method to the measurement of Achilles' tendon thickness in familial hypercholesterolemia. They have not found a significant increase of the thickness, unless patients with xanthomas were included. Statistical value of the method is thus contested.
The liver and primary type IV hyperlipoproteinaemia: a pathological study.
We studied the histological structure of the livers of 36 patients presenting type IV primary hyperlipoproteinaemia. Electron microscopy revealed dilation of the smooth endoplasmic reticulum and rough endoplasmic reticulum as well as the presence of giant mitochondria containing para-crystalline inclusions. Steatosis was present in all type IV hyperlipoproteinaemic patients regardless of their weight or nutritional sensitivity (to alcohol or carbohydrate). The ultrastructural modifications observed by electron microscopy indicate an increased synthesis of very-low-density lipoproteins by the hepatocytes. An alteration in excretion cannot be ruled out with certainty even though the microfilamentary microtubular system was intact, since the qualitative and functional modifications in this system may be undetectable by electron microscopy.
Comparative study of four HDL-cholesterol assay methods.
Four methods for HDL-cholesterol assay are compared using the plasma of 119 subjects. Results for the entire population and for subgroups defined by triglyceridemia and cholesterolemia levels are determined. The methods used are: ultracentrifugation, electrophoresis, dextran sulfate precipitation, and concanavalin A precipitation. The results indicate that ultracentrifugation and electrophoresis are not easily adapted to routine work, require large investments and do not separate the lipoproteins according to physiopathological criteria. The HDL values obtained with the different methods show significant differences, even though the correlations between the methods are highly significant. The precipitation methods are easiest to perform; however, the HDL-cholesterol values from dextran sulfate precipitation are higher than those from concanavalin A precipitation. The authors discuss the best choice for determining the atherogenic risks of hyperlipoproteinemia in clinical practice.
Pyometra.
Pyometra is a potentially lethal disease. Eighteen cases, all but one in postmenopausal women, were diagnosed at the Ottawa General and Ottawa Civic hospitals between 1974 and 1978 inclusive. A review of this series and of the literature demonstrates that a large proportion of cases (72% in this series) are associated with or follow radiotherapy for a malignant disease of the uterus and that anaerobic bacteria are frequently isolated from the uterine cavity (in 56% of the patients in this series). Because pyometra is potentially lethal (one patient in our series died) it should be considered as an abscess and treated promptly and vigorously by evacuation and continued drainage of the uterine cavity. Curettage of the cavity and the endocervical canal after dilatation is essential to rule out associated malignant disease as well as to debride the necrotic tissue. Antibiotics effective against aerobic and anaerobic bacteria should be given to all patients with signs of systemic infection. Once the infection is controlled, the underlying problem can be treated.
Biological variations in hyperlipidemic children and adolescents treated with fenofibrate.
Beside their pharmacological action drugs may have unexpected side effects which must be known and taken into account in the interpretation of laboratory tests. In this work, we followed 17 hyperlipidemic subjects, aged 4-19 years, treated with fenofibrate only. We performed several plasma tests before and during treatment. The hypolipidemic action of fenofibrate was evident: decreases of cholesterol and triglycerides mean values were, respectively, 22% and 39% after 3 months of treatment. Other plasma constituents were also significantly decreased: uric acid, 20%; bilirubin, 19%; alkaline phosphatases, 15%. The aminotransferase activities (both AST and ALT) were increased in only four subjects after 3 months. The highest values were 88 U/l for AST and 109 U/l for ALT (the initial values were, respectively, 28 U/l and 23 U/l). These activities decreased when the treatment was stopped. These variations were isolated and transient.
Postradiation ureteral obstruction: a reappraisal.
Thirty-four patients who received radiation therapy for carcinoma of the cervix developed hydronephrosis. Twelve of 34 (35%) had no evidence of pelvic malignancy, and the obstruction was caused by periureteral fibrosis. The incidence of obstructive uropathy due to periureteral fibrosis not associated with recurrent tumor increased when the obstructing lesion was unilateral, the clinical staging of the cervical carcinoma prior to therapy was Stage IB or Stage II rather than Stage III or Stage IV, and the obstructing lesion appeared 2 or more years after the completion of radiation therapy. The appearance of hydronephrosis in association with ipsilateral leg edema, and sciatic pain these patients strongly suggest a recurrent tumor. The diagnosis of periureteral fibrosis should be considered in all patients who develop obstruction of the urinary tract after radiation therapy for carcinoma of the cervix. Laparotomy is indicated if all other methods of investigation fail to confirm the presence of a malignant lesion.
Indirect evidence of the formation of high molecular weight immunoreactive insulin (HWIRI) in the circulation of man.
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Degradation during storage of high molecular weight immunoreactive insulin (HWIRI) and proinsulin (PLC) in extracts of Benign insulinomas and adjacent pancreatic tissue.
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Effects of liver and kidney on high molecular weight immunoreactive insulin (HWIRI), proinsulin (PI) and insulin (I) in man.
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Venous plethysmography: measuring techniques and normal values.
A fixed procedure of strain gauge plethysmography in a control population aged between 20-30 years allows normal values for venous parameters (venous distensibility, emptying, and resistance) and capillary filtration coefficient, to be determined. High speed recording reveals two phases in venous emptying, one passive, purely elastic, and a second active phase, resulting from venous constriction.