Biomedical subjects

P Dupuy

Publications and source records attributed to P Dupuy.

At least 73 records · Page 4Linked to original sources

PubMed1990

Portal and hepatic arterial blood flow measurements of human transplanted liver by implanted Doppler probes: interest for early complications and nutrition.

Hepatic artery thrombosis and early acute rejection are severe complications of orthotopic liver transplantation (OLT). Their rapid detection is most desirable. The purpose of this study was to assess the usefulness of monitoring hepatic artery (HABF) and portal vein (PVBF) blood flows during the first week after OLT. At the end of operation, microprobes were sutured to the vessels, and their connecting tubes were externalized and connected to a pulsed Doppler flowmeter operating at 8 MHz. In 10 patients (ages ranged from 2 to 54 years) of 106, measurements of HABF and PVBF were done during alternative clamping of both vessels and before and after abdominal closure, every 12 hours during 7 days, and at day 7, before and after a 150 gm carbohydrate meal. At day 7 the probes were pulled out by gentle traction without complication, and all patients were allowed to go home. Reciprocal increase of flow during selective clamping was only observed for HABF (+45.8% +/- 47.6%; p less than 0.01). Abdominal closure decreased both HABF and PVBF by 13.8%, p less than 0.01, and 26%, p less than 0.05, respectively. In seven cases no significant variation of HABF and PVBF was observed during 7 days. In two patients with histologically confirmed early acute rejection, a marked decrease of diastolic HABF, without modification in PVBF, was the first manifestation and was rapidly corrected by boluses of steroids. In one patient disappearance of systolic and diastolic HABF led us to diagnose an arterial obliteration caused by a plicature, which was successfully surgically treated in the emergency department. In all patients, after oral ingestion of the carbohydrate meal, and only after this type of diet, a significant and deep decrease (-87%, p less than 0.001) of HABF was observed between 7 and 120 minutes without any change in PVBF. Such an effect was not observed in control patients. We conclude that this Doppler flowmetric technique with implantable microprobes is useful for rapid diagnosis of and strategy in treating early complications and is a new tool for pathophysiologic study of OLT consequences.

Dietary Carbohydrates↗

PubMed1989

Synthetic retinoids inhibit the antigen presenting properties of epidermal cells in vitro.

The clinical efficacy of retinoids in benign and malignant skin diseases involving immune mechanisms suggests that they affect the immunologic functions of the epidermis. However, these effects have yet to be demonstrated. The action of vitamin A (retinol) and the synthetic retinoids, isotretinoin, etretinate, acitretin, and arotinoid-free acid have been studied on the lymphocyte proliferation induced by phytohemagglutinin (PHA), by the mixed lymphocyte reaction (MLR), and the mixed epidermal cell-lymphocyte reaction (MECLR). The results for PHA-induced proliferations were highly variable for all the retinoids. However, in MECLR, the synthetic retinoids consistently reduced the proliferation by 20%-30%. This occurred at therapeutic drug concentrations of about 10(-7)M. In MLR, a minor decrease of 10%-15% was only found for higher concentrations (10(-5)M). Retinol induced no effect in either reaction. Further analysis of acitretin on MECLR showed that it reduced lymphocyte proliferation in a dose-dependent fashion. This reduction was combined with a decrease in cytotoxic T-lymphocyte induction (CTL). Addition of 10(-6)M acitretin at various times also revealed that its presence at cell culture initiation was necessary to inhibit proliferation significantly. Furthermore, cell treatments prior to MECLR showed that exposure of epidermal cells to acitretin was essential to produce this inhibition, suggesting that it acts directly on epidermal cells. Consequently, it is suggested that the specific inhibitory effect of synthetic retinoids on lymphocyte activation in MECLR may partly account for their therapeutic action on the skin.

Acitretin↗

PubMed1989

Pancreatic stone protein: quantification in pancreatic juice by enzyme-linked immunosorbent assay and comparison with other methods.

To quantitate pancreatic stone protein (PSP), a competitive radioimmunoassay using monoclonal antibodies to PSP extracted from pancreatic stones and a sandwich enzyme-linked immunosorbent assay (ELISA) using monospecific polyclonal antibodies to the secretory forms of PSP (PSP S) were established. When PSP concentrations were measured in pancreatic juice by radioimmunoassay, no difference could be found between patients suffering from chronic calcifying pancreatitis and other diagnostic groups. Yet, with the ELISA technique involving polyclonal antibodies, decreased concentrations were found in chronic calcifying pancreatitis patients when compared to controls (p less than 0.001), chronic alcoholics without pancreatic symptoms, or obstructive pancreatitis patients. These discrepancies are discussed. The monoclonal antibodies recognizing the C-terminal part of PSS S (PSP S1), results from the radioimmunoassay indicate that the concentration of that polypeptide is identical in the juice of controls and patients. Results from the ELISA obtained with polyclonal antibodies raised against PSP S2-5 molecules, i.e., recognizing the PSP S1 part and the N-terminal portion of the molecule, indicate that the differences observed reflect differences in the juice concentration of that N-terminal peptide.

Antibodies↗

PubMed1989