PubMed Health⌕ Search

Biomedical subjects

J L Vanherweghem

Publications and source records attributed to J L Vanherweghem.

At least 127 records · Page 7Linked to original sources
PubMed1976

Effects of hypercalcemia on water and sodium excretion by the isolated dog kidney.

The effects of acute hypercalcemia on hemodynamics and on water and sodium excretion were studied on the blood-perfused isolated dog kidney. This model advantageously eliminates various factors which modify medullary osmolality and intrarenal hemodynamics, as well as collecting duct permeability. Calcium ion directly inhibits sodium reabsorption in the proximal tubule and in the ascending limb of Henle's loop, leading to increased sodium excretion rate and to decreased free water generation. The vasoconstrictive action of calcium, leading to decreased glomerular filtration rate, may mitigate the strong natriuretic effect of this ion.

Animals↗
PubMed1975

Effects of indomethacin on renal hemodynamics and on water and sodium excretion by the isolated dog kidney.

Blood-perfused isolated dog kidneys demonstrate steady increases in blood flow and in water and sodium excretion which could be attributed to the accumulation of renal prostaglandins in the perfusing blood. This hypothesis was tested by adding indomethacin, a potent inhibitor of prostaglandins synthesis, to the perfusing blood. Indomethacin completely prevented the vasodilation observed in control kidneys, without affecting glomerular filtration rate. Urine volume was not modified but sodium excretion was enhanced while the steady free water clearance increment observed in the control kidneys was depressed by indomethacin. The sum of sodium and free water clearances which, in the absence of antidiuretic hormone, constitutes an index of the part of the filtered load of solutes which escapes proximal tubular reabsorption, was not modified by indomethacin. Finally, indomethacin partially maintained the osmotic cortico-papillary gradient which was abolished after 2 hrs perfusion in control kidneys. These data suggest that prostaglandins accumulation in the blood is probably the major cause of the vasodilation taking place in isolated blood-perfused kidneys. This vasodilation does not account for decreased proximal reabsorption but partially explains the ADH-resistant diabetes insipidus developing in the isolated kidney. Moreover, indomethacin inhibits sodium reabsorption in the ascending limb of Henle's loop and increases water transport in the collecting duct.

Animals↗
PubMedDate not supplied

Differential diagnosis between secondary hyperparathyroidism and aluminum intoxication in uremic patients: usefulness of 99mTc-pyrophosphate bone scintigraphy.

Forty-one patients in chronic end-stage renal failure and 4 patients with a functioning kidney transplant presented with spontaneous hypercalcemia or intolerance to vitamin D3 sterols and/or oral calcium supplements. Bone iliac crest biopsy with aluminum staining and Tc-pyrophosphate bone scintigraphy with determination of Fogelman score were performed in all cases. Two patients had aluminum-induced osteomalacia (AL O). Thirty-eight biopsies showed renal osteodystrophy (secondary hyperparathyroidism or various combinations of osteitis fibrosa and osteomalacia): 19 with positive staining for aluminum (RO + AL) and 19 without aluminum deposits (RO). The series also comprised 2 cases of pure osteomalacia (OM), 2 cases of osteoporosis (OP), and 1 case of osteoporosis with aluminum accumulation (OP + AL). Mean Fogelman score in RO patients (9.1 +/- 0.3) was significantly higher than in all other categories (5.9 +/- 0.5 for RO + AL, and scores ranging from 0 to 8 in the last 7 patients, p less than 0.01). Patients with massive aluminum accumulation in bone (greater than 75% of the total trabecular surface) showed no or very low uptake of the isotope by the skeleton. Fogelman scores of 9 or higher were always associated with histological secondary hyperparathyroidism. 99mTc-pyrophosphate bone scintigraphy is helpful to distinguish aluminum intoxication from secondary hyperparathyroidism in uremic patients.

Adult↗
PubMedDate not supplied

Use of the Hickman catheter as permanent vascular access for hemodialysis.

Nineteen patients in whom it was impossible to create an arteriovenous (AV) fistula were hemodialyzed with adult Hickman catheters as the sole vascular access. Catheter survival was 45% at 1 year, with eight patients requiring two or three catheters for the continuation of their treatment. The probability of a patient still being dialyzed with a Hickman catheter at 1 year was 69%. The calculated risk of developing the most frequent complications was 0.07/100 catheter days for sepsis, 0.4/100 catheter days for thrombosis, and 0.06/100 catheter days for outflow obstruction. These figures seem quite acceptable, and the use of Hickman catheters as permanent vascular access is warranted in this category of difficult patient.

Adult↗
PubMedDate not supplied

[Implantation technic and maintenance of a Hickman catheter for hemodialysis].

Description of the technique of insertion of the Hickman catheter for hemodialysis based on 110 operations. Absolute prerequisites for correct functioning are: 1) Fluoroscopic control of the localization of this device in the superior vena cava and 2) Checking if adequate flow can be obtained.

Catheterization, Central Venous↗
PubMedDate not supplied

Complement activation and leucopenia on cellulosic haemodialyzers: influence of the membrane area and role of hydroxyl moieties.

We analysed the impact of the area of the dialysis membrane and of its content in hydroxyl moieties on the magnitude of haemodialysis-induced complement activation and leucopenia. First, in five patients successively treated with cellulose acetate membranes of different areas, we found that increase of the area results in an increase in complement activation determined by C3a levels before and at 15 min of dialysis. The levels of leucopenia were similarly affected, and a significant correlation was found between complement activation and leucopenia (r = 0.89, P less than 0.05). When we compared the biocompatibility characteristics of a dialyser made of saponified cellulose ester with those of two dialysers made of cellulose acetate, we found that index of complement activation (18.1 +/- 2 vs 9.9 +/- 1.1 and 11.5 +/- 1.1, P less than 0.01) as well as index of leucopenia (69 +/- 4 vs 40 +/- 2 and 37 +/- 3, P less than 0.001) were significantly higher on the saponified cellulose ester dialysers suggesting that hydroxyl groups of cellulosic membranes play an important role in the pathophysiology of dialysis-induced changes.

Biocompatible Materials↗
PubMedDate not supplied

[Acute renal insufficiency in surgery: the surgeon's role].

The surgeon has an active role to play in the treatment of acute renal failure (ARF) occurring in surgical patients. Surgical complications are very often the cause of ARF and their treatment is the only way to cure uremia.

Acute Kidney Injury↗