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Biomedical subjects

M Jadoul

Publications and source records attributed to M Jadoul.

At least 73 records · Page 4Linked to original sources
PubMed1994

An ELISA for the measurement of human leukemia inhibitory factor in biological fluids and culture supernatants.

A new monoclonal antibody-based ELISA for leukaemia inhibitory factor/human interleukin for DA cells (LIF/HILDA) measurements is described. The sensitivity (56 pg/ml after 4 h incubation, 14 pg/ml after 24 h incubation), precision (intra-assays < 5%), reproducibility (interassay < 10%), and accuracy (recoveries, ranging between 98 and 119%, in several fluids) of the assay, plus its excellent performance in dilution tests, and the lack of interference when in the presence of possible cross-reactive substances guarantee accurate cytokine measurement in biological fluids such as serum, plasma, synovial fluid, follicular fluid, urine and culture supernatants. Using the assay, LIF/HILDA was measurable in supernatants after in vitro whole blood stimulation with phytohemagglutinin (PHA), OKT3, and phorbol myristate acetate (PMA) but not with lipopolysaccharide (LPS) or Ca ionophore. LIF/HILDA production was not measurable until after 24 h of culture, when cytokine levels were seen to increase linearly in the supernatant to reach values of up to 40 ng/ml after 96 h of culture. Finally, a good correlation was found (r = 0.96; p < 0.0001; y = 23.1x + 233) between the LIF/HILDA values obtained using the ELISA and DA-1a bioassay.

Adult↗
PubMed1994

Chinese herbs nephropathy: a clue to Balkan endemic nephropathy?

Rapidly progressive interstitial renal fibrosis has recently been reported in young women who have been on a slimming regimen including Chinese herbs. We examined four nephroureterectomies performed in three patients prior to or at the time of transplantation to determine the nature and topography of the kidney and urinary tract lesions in Chinese herbs nephropathy (CHN). Extensive, hypocellular, interstitial sclerosis, tubular atrophy and global sclerosis of glomeruli decreasing from the outer to the inner cortex, including the columns of Bertin, were observed in the four kidney specimens, together with severe fibromucoid to fibrous intimal thickening, mainly of interlobular arteries, normal or collapsed residual glomeruli, and mild to moderate atypia and atypical hyperplasia of the urothelium. In addition, bilateral pelvi-ureteric sclerosis was observed in one case. With the exception of the latter, these lesions are very similar to those described in Balkan endemic nephropathy (BEN). The clinical presentation of the patients was also similar to that observed in BEN: normal blood pressure, aseptic leukocyturia, low grade low molecular weight proteinuria, early and severe anemia. In conclusion, on morphological and clinical grounds, CHN appears similar to BEN. A common etiologic agent, aristolochic acid, is suspected. The known carcinogenic potential of this compound, taken together with our finding of multiple foci of cellular atypia of the urothelium suggest that CHN patients should undergo a regular follow-up for urothelial malignancy.

Adult↗
PubMed1994

Determinants of the serum concentrations of low molecular weight proteins in patients on maintenance hemodialysis.

Factors influencing the serum concentrations of low molecular weight proteins (LMWP) during long-term hemodialysis were studied in 112 patients undergoing dialysis for an average of 61.1 months (range 1 to 243). These patients were treated with AN69, cellulose acetate, cuprophan or polysulfone membranes. The following proteins were measured in serum before and after a four hour dialysis session: cystatin C (CYST C), beta 2-microglobulin (beta 2 m), Clara cell protein (CC16) and retinol-binding protein (RBP). Predialysis levels of the four proteins were markedly elevated. In simple regression analysis, pre-dialysis serum concentrations of beta 2 m and CC16 weakly correlated with the duration of dialysis treatment, but these relations completely disappeared when a stepwise regression analysis was performed using as predictors age, sex, residual diuresis, body weight loss (BWL), duration of hemodialysis and the type or ultrafiltration coefficient (UFC) of the membranes. The only significant determinants which emerged from this analysis were the residual diuresis and age which negatively correlated with CYST C, beta 2m and CC16 (residual diuresis only), and sex which influenced CYST C. During the dialysis session, the microproteins underwent changes that were related to their molecular radius, the membrane UFC and the BWL. After adjustment for the latter, high flux membranes (UFC > or = 15 ml/h.m2.mm Hg) allowed up to 50% of CYST C and 25% of beta 2m to be removed. No significant elimination of CC16 and RBP was evident. On the basis of these results, we estimated the effective pore radius of high flux membranes between 1.5 and 1.7 nm and that of low flux membranes as below 1.5 nm.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Proteins↗
PubMed1993

Novel method for the measurement of cytokine production by a one-stage procedure.

A new one-step culture-immunoassay procedure is described for testing cytokine production by immunocompetent cells in whole blood (WB) without the need for an isolation step. Briefly, WB samples or distilled water were added to RPMI medium containing specific anti-cytokine peroxidase-labelled monoclonal antibodies and incubated in micro-well plates coated with specific capture monoclonal antibodies, directed against distinct epitopes of the cytokine, and containing dried polyclonal activators (5.625 micrograms LPS + 1.125 micrograms PHA) or dried standards respectively. The optimalisation of the assay is described for an extended measurement range. The best compromise between sensitivity and linearity was obtained with the addition of 50 ng/well for TNF-alpha and IL-6 or 100 ng/well for IFN-gamma of unconjugate antibodies to the corresponding conjugate. The kinetics of individual production of each cytokine in WB of normal healthy donors showed values entering the standard range following incubation times of between 2 and 8 h for TNF-alpha, 2 and 4 h for IL-6, and 4 and 24 h for IFN-gamma. The sensitivity, the precision (intra-assay CVs) and the reproducibility (interassay CVs) of the assays were as follows: 70 pg/ml, < or = 14% and < or = 11% for TNF-alpha; 25 pg/ml, < or = 11% and < or = 16% for IL-6; 25 pg/ml, < or = 19% and < or = 20% for IFN-gamma. The accuracy (% of recovery) of the assays was in the order of 100% and between 40 and 60% in the absence or presence of polyclonal activators, reflecting the occurrence of an active production/consumption mechanism during the activation.

Adult↗
PubMed1993

Rapidly progressive interstitial renal fibrosis in young women: association with slimming regimen including Chinese herbs.

Two similar cases of rapidly progressive fibrosing interstitial nephritis in young women who followed the same slimming regimen prompted us to conduct an epidemiological survey of the nephrology centres of Brussels and to further investigate the exact nature of this slimming treatment. Seven other women under the age of 50 in terminal or preterminal renal failure were admitted for dialysis in 1991 and 1992. They had all followed a slimming regimen in the same medical clinic. Renal biopsy samples in eight of the nine cases showed extensive interstitial fibrosis without glomerular lesions. Two of the patients were seen for the first time in terminal renal failure and were started immediately on dialysis. For the seven other women, the nephropathy was characterised by a rapid deterioration in renal function, with initial serum creatinine doubling within about 3 months. The clinic had specialised in slimming treatments for the previous 15 years without any problems. In May, 1990, therapy was changed, with the introduction of two Chinese herbs (Stephania tetrandra and Magnolia officinalis). In June, 1992, three of twenty-five randomly selected women who had followed the same regimen during at least 3 months from 1990 had impaired renal function. Chemical analysis of some brands of these Chinese herbs did not show nephrotoxic contaminants of fungal or plant origin (ochratoxin or aristolochic acid) or adulteration by diuretics or antiinflammatory drugs. However, the medicinal preparation of the capsules taken by patients had different alkaloid profiles from those expected in Chinese plants. The striking relation between a specific type of fibrosing interstitial nephritis in young women and a slimming treatment involving Chinese herbs adds support to the arguments against uncontrolled therapy with herbal preparations.

Adult↗
PubMed1993

Generation of monoclonal antibodies against HILDA/LIF and their use in the quantitative assay of the cytokine.

An adoptive transfer immunization/fusion protocol in mice has been successfully used to raise a series of monoclonal antibodies directed against the Human Interleukin for DA-1a (HILDA)/Leukemia Inhibitory Factor (LIF) cytokine. These antibodies which were raised using recombinant HILDA/LIF purified from conditioned medium of transfected Chinese Hamster Ovary (CHO) cells also react with natural HILDA/LIF from the HSB2 T lymphoma cell line and unglycosylated HILDA/LIF produced in E. coli. They define four separate epitopes, one of which is involved in receptor binding and induction of biological activity. A sensitive sandwich immunoradiometric assay which is linear up to 5 ng/ml HILDA/LIF and can detect as low as 25 pg/ml of the cytokine has been developed.

Animals↗
PubMed1993

Incidence and risk factors for hepatitis C seroconversion in hemodialysis: a prospective study. The UCL Collaborative Group.

To delineate the incidence and risk factors for seroconversion (SC) for HCV, from May 1991 to November 1992 we followed all 401 patients (no i.v. drug abusers) dialyzed in 15 Belgian hemodialysis (HD) units, none of which isolates anti-HCV (+) patients. The sensitive ELISA II test was performed in the same laboratory for all patients. ELISA II (+) sera were considered truly positive if specific antibodies were detected by RIBA II against at least one HCV antigen. Blood transfusions given from 12 months prior to inclusion in the study, dialyzer reuse and frequency of dialysis monitor sterilization were recorded. In May 1991, prevalence of truly positive ELISA II tests averaged 13.5% (54/399). During the three consecutive six-month periods, ELISA II became truly positive in 3 of 305 (1%), 4 of 314 (1.3%) and 1 of 313 (0.3%) patients, respectively, which was an average yearly incidence of 1.7%. SC was preceded (1 to 6 months) in all cases by an unexplained, unprecedented increase in the alanine aminotransferase level. The mean monthly rate of transfusions was significantly higher (P < 0.001) in eight patients with SC (0.7 +/- 0.6 U) than in 393 patients without SC (0.1 +/- 0.01 U). However, three of eight patients with SC had not been transfused at all. SC was observed in only 3 of 13 units (1, 3 and 4 cases, respectively) dialyzing ELISA (+) patients. In the unit with three SC, patients were always assigned a fixed station: SC was observed only in patients dialyzed next to an ELISA II (+) patient (3 of 8 vs. 0 of 30, P < 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Ultrasonographic detection of thickened joint capsules and tendons as marker of dialysis-related amyloidosis: a cross-sectional and longitudinal study.

Dialysis-related amyloidosis is characterized by a beta 2-microglobulin (beta 2M) infiltration of joint synovia, tendons and capsules. We report a cross-sectional ultrasonographic evaluation of supraspinatus tendon and femoral neck capsule thickness in 49 patients on long-term haemodialysis. Ultrasonographic evaluation was repeated 21 +/- 4 (SD) months later in 16 patients. Normal values for the supraspinatus tendon and femoral neck capsule were defined in a group of control subjects without history or signs of joint disease. Among the 49 patients, aged 21-86 (median 59) years, dialysed for 1-228 (median 97) months, 33 had at least one abnormal joint. The prevalence of patients with at least one and at least two abnormal joints, the number of abnormal joints per patient, and the thickness of the supraspinatus tendon and femoral neck capsule increased significantly with dialysis duration (P < 0.001 for all parameters considered). By multiple linear regression analysis, mean thickness of the supraspinatus tendon was positively related to both dialysis duration (P < 0.0001) and age (P = 0.036) independently. All (n = 11) patients with radiological and/or histological evidence of dialysis-related amyloidosis at the time of ultrasonography had thickened supraspinatus tendon and/or femoral neck capsule; which were also thickened in an additional 22 patients without radiological evidence of dialysis-related amyloidosis. Three died within 5-10 months of the ultrasonographic investigation: post-mortem examination of the periarticular tissue confirmed that the detected thickening was due in all three to beta 2M amyloid infiltration.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Ultrasonography of joint capsules and tendons in dialysis-related amyloidosis.

Beta-2-microglobulin (beta 2m) amyloid infiltrates joint synovia, tendons and capsules. We report a cross-sectional ultrasonographic (US) evaluation of supraspinatus tendons' (SST) and femoral neck capsules' (FNC) thickness in 49 patients on long-term hemodialysis. Normal values for SST and FNC were defined in control subjects. Among the 49 patients, aged 21 to 86 (median 59) years at the time of US, dialyzed for 1 to 228 (median 97) months, 33 had at least one abnormal joint. The prevalence of patients with at least one or at least two abnormal joints, the number of abnormal joints per patient and the thickness of SST and FNC increased significantly with dialysis duration (P < 0.001 for all parameters considered). All (N = 11) patients with radiological and/or histological evidence of dialysis-related amyloidosis (DRA) had thickened SST and/or FNC. Twenty-two other patients without similar evidence of DRA also had thickened FNC and/or SST. Three died; post-mortem examination demonstrated that US abnormalities were due to beta 2m amyloid infiltration. We suggest that SST and FNC thickness, measured by US, is a useful, non-invasive tool for the diagnosis of DRA.

Adolescent↗
PubMed1992

Direct stimulation of cytokines (IL-1 beta, TNF-alpha, IL-6, IL-2, IFN-gamma and GM-CSF) in whole blood: II. Application to rheumatoid arthritis and osteoarthritis.

Rheumatoid arthritis (RA) is an immune disease in which the pathological immune reaction is thought to be initiated by the presentation of an (auto) antigen or superantigen by MHC class II positive cells to CD4 T cells. These successive immunological events can be studied by the cytokines produced at the different stages. Cytokine secretion by stimulated cells in autologous diluted whole blood has allowed the study of the immune profile characteristic of rheumatoid arthritis. The pattern of RA patient whole blood cells cultured in autologous blood is characterized by hyperactivity of the mononuclear cells with high secretion of IL-1 beta, TNF-alpha and IL-6 and low production of IFN-gamma, in comparison with the normal (N) and osteoarthrosis (OA) populations. The IL-2 secretion pattern is unique, arising from production followed by consumption. This production-consumption turnover is the most elevated in the RA group. The T cells are indeed activated in rheumatoid arthritis but regulatory events suppress some of their functions. A correlation was found between the inflammatory proteins and mediators of cellular immunity and macrophagic function: IL-1 beta and the sedimentation rate; IL-6 and fibrinogen; TNF-alpha and the number of blood monocytes. The secretion of OA-stimulated whole blood cells was similar to RA for two monokines (overproduction of TNF-alpha and IL-6) and different for IL-1 beta, not different from normal in OA. Stimulated whole blood cell cytokine secretion profile from RA and OA groups, was the same as previously observed in synovial fluid.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Mineralocorticoids in the management of primary adrenocortical insufficiency.

Plasma renin activity (PRA) and plasma volume (PV) were determined in 22 adult patients treated for Addison's disease (AD) and reporting at the clinic for follow-up. Mean PRA was thrice the upper limit of normal (9.1 +/- 7.1 ng/ml/h (SD)) and mean PV was decreased (87% +/- 11 (SD)), consistent with residual hypovolemia in most patients, despite conventional treatment with both fluorocortisol (FF) and cortisone acetate. There was an inverse relationship between PRA and PV. Both PRA and PV were significantly correlated with FF dosage. On the other hand, no correlation was found between PV and either systolic or diastolic blood pressure (BP), while PRA was significantly correlated with systolic but not diastolic BP. Four patients were persistently hypertensive (diastolic BP greater than 100 mmHg) with elevated PRA in 3, associated with a definitely low PV in two cases. Two of these patients were progressively taken off FF, so as to control BP. Thus, in view of the not infrequent occurrence of arterial hypertension in AD patient on conventional treatment, we would warn against attempts at normalizing PV and PRA by means of FF, irrespective of BP in asymptomatic cases. In fact, when hypertension develops, reduction or sometimes withdrawal of FF may be recommended as a first therapeutic step.

Addison Disease↗
PubMed1991

Effect of dialysis membrane and patient's age on signs of dialysis-related amyloidosis. The Working Party on Dialysis Amyloidosis.

This 12 center study was designed to assess factors affecting the development and progression of beta 2-microglobulin amyloidosis in long-term dialysis. A total of 221 patients who were on hemodialysis for more than five years, and who were treated the entire time only with AN69, a biocompatible, highly permeable membrane, or cuprophane, a less permeable, poorly biocompatible membrane (Cell) were evaluated for time on dialysis, development of carpal tunnel syndrome, and cystic bone lesions. X-ray documentation was taken in a minimum of four of the six following joints: both hips, wrists and shoulders. The data demonstrate that patients treated solely by AN69 membranes display signs of bone amyloidosis less frequently than do those treated by Cell membranes. Age at onset of dialysis was found to have a striking correlation with the development of carpal tunnel syndrome and bone amyloidosis, while no significant influence was found for hyperparathyroidism, sex or year of first dialysis.

Acrylic Resins↗