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T Haas

Publications and source records attributed to T Haas.

At least 19 recordsLinked to original sources
PubMed1995

Pre-/postdilution hemofiltration.

Hemofiltration creates the best conditions for toxin removal and cardiovascular stability in the treatment of chronic renal failure patients. The increase in hematocrit due to erythropoietin, the blood flow rate and the necessary volume of substitution fluid limit the post- or the predilution hemofiltration. The technical progress made now offers the possibility to routinely and safely treat patients with pre-/postdilution hemofiltration. When adjusting the substitution flow rate to the blood flow rate, small-molecule clearances are higher than those in hemodialysis and are close to those in hemodiafiltration.

Hemodilution↗
PubMed1994

[Relation between hypertriacylglycerolemia and the action of insulin in type 2 diabetes mellitus].

BACKGROUND: Insulin resistance and hypertriacylglycerolaemia are part of the X syndrome and are supposed to be interrelated. The objective of the present trial was to evaluate the impact of hypolipidaemic treatment on the action of insulin evaluated by means of a so-called hyperinsulimaemic clamp and by examination of insulin receptors. METHODS AND RESULTS: To eight type 2 diabetics with mild hypertriacylglycerolaemia for three months ethophylline clofibrate (Duolip) was administered and for three months phenofibrate (Lipanthyl). Before and during treatment parameters of diabetes compensation were examined (blood sugar level, fructosamine and glycolysate haemoglobin), insulin sensitivity, using an isoglycaemic hyperinsulinaemic clamp and insulin receptors on red blood cells. Lipanthyl caused a more marked drop of triacylglycerol (by 46%) than Duolip forte (by 20%). Hypolipidaemic treatment did not affect diabetes compensation. As compared with healthy subjects, in diabetics before treatment a reduced insulin sensitivity was found, evaluated either by the index of insulin sensitivity (24.0 +/- 0.8, as compared with 35.5 +/- 4.9 mumol/kg/min per mU/l x 100, p < 0.05) or metabolic glucose clearance (3.7 +/- 0.9, as compared with 6.3 +/- 1.0 ml/kg/min, p < 0.01) and a slightly reduced insulin bond with receptors (p < 0.05). Duolip treatment led to a drop of insulin sensitivity and concurrent rise of affinity of insulin receptors (p < 0.01), while Lipanthyl was not manifested by marked changes. The authors did not find a significant correlation between the drop of triacylglycerol levels and insulin sensitivity in different types of treatment, which obviously is due to the small number of examinations. CONCLUSIONS: Therapy with ethophylline clofibrate of fenofibrate was not manifested in type 2 diabetics by a changes in the compensation of the disease. Hypertriacylglycerolaemia exists as an independent factor which is rather the consequence than cause of insulin resistance.

Adult↗
PubMed1994

Risk calculation of type 2 diabetes.

The paper presents an analysis of the risk of developing Type 2 diabetes according to family history and anthropometric variables. The age of diabetes onset was analysed in 2024 diabetics. We obtained several groups according to family history. In each group taken separately, the data describing the cumulative percentage of diabetes onset was fitted by logistic curve F(x) = p1/(1 + p2*p3((x/10)-p4)). Comparing these curves we see that cumulative age-dependent risk increases from the group of randomly chosen persons through the group of first degree relatives to the children of diabetics. The highest risk of diabetes onset is determined by the curve representing the group of known diabetics. Another analysis was performed in a different group of 390 obese subjects (34 diabetics among them). Male diabetics had significantly higher body mass index (BMI) and weight than male non-diabetics. Female diabetics showed significantly higher weight, body mass index, waist to hip ratio (WHR) and age than female non-diabetics. Elimination of factors with randomization and matching showed a complicated relationship between diabetes, age and anthropometric variables. Using stepwise logistic regression we obtained the model for prediction of diabetes risk based on age, BMI, WHR: probability of diabetes = exp(u)/(1 + exp(u)), where u = -13.9 + 0.05431*age + 6.789*WHR + 0.07881*BMI for obese women, u = -11.84 + 10.01*WHR for obese men. In conclusion, genetic factors are the most important and can be exactly quantified in Type 2 diabetes. The importance of anthropometric variables for prediction of diabetes risk is also presented.

Adult↗
PubMed1993

Adolescent obesity and cardiovascular risk: a rational approach to management.

Ten obese adolescents, referred because of elevated cardiovascular disease risk, were treated in a pediatric atherosclerosis prevention center. The focus of treatment was an increase in exercise tolerance and aerobic capacity and a decrease in the percentage of fat in the diet. Weight loss was not a goal of treatment, but continued growth with a slowing of the rate of weight gain was emphasized. All patients were at elevated cardiovascular risk at the entry to the study, and nine of the ten had significant improvements in one or more of their cardiovascular risk parameters. Furthermore, with regard to body composition, eight of the ten patients were able to improve their body mass index. On average, triceps skinfold thicknesses declined 25 percent. Total cholesterol declined 14%, triglycerides declined 33%, LDL cholesterol declined 13%, and HDL cholesterol did not change with this form of treatment. As for systolic and diastolic blood pressure, four of the ten patients who had elevated blood pressures at the initiation of treatment were able to decrease their blood pressure, in absolute terms and on the basis of their percentiles for age and sex. We conclude that, in obese adolescents, improved diet and body composition, a slowed rate of weight gain, and a reduction of cardiovascular risk shown through lipid profiles and blood pressures can be achieved from a multidisciplinary treatment program focused on achievable goals. These goals include (1) increased habitual exercise and increased aerobic exercise and (2) a decrease in the percentage of energy intake from fat and saturated fat, with a concomitant decrease in the balance of energy intake to energy output. It is important to remember that we did not focus on weight loss per se and that the treatment was individualized to the developmental stage of the adolescent.

Adolescent↗
PubMed1991

[Hemofiltration--Hemodiafiltration].

Hemofiltration and hemodiafiltration are two modes of extra-renal therapy which characteristics are: high efficiency, biocompatibility, good tolerance, low morbidity. On-line preparation of substitution fluid from sterile and apyrogen dialysate and modelization lead to propose in the futur HF ou HDF for all patients. Adequacy of epuration is not enough defined to conclude that HDF is better than HF.

Dialysis↗
PubMed1991

A six-year follow-up of the relationship between N-acetyl-beta-glucosaminidase and albuminuria in relation to retinopathy.

Fifty patients with Type 1 diabetes mellitus were observed over 6 years. Serum and urinary N-acetyl-beta-glucosaminidase (NAG) activity, and albuminuria were measured in groups of patients subdivided according to ophthalmological findings. Significantly higher mean serum NAG activity was found at the beginning of the study in patients who later developed diabetic retinopathy in comparison with those who did not (geometric mean (2SD range) 19.7 (12.4-31.2) vs 14.4 (9.5-22.7) U l-1, p less than 0.01). Urinary NAG activity was significantly higher in all groups of diabetic patients than in healthy control subjects (p less than 0.05). A significant increase in albumin:creatinine ratio during the study was found in patients with newly developed diabetic retinopathy compared with patients who did not (at 6 years 1.33 (0.40-4.43) vs 0.75 (0.24-2.31) g mol-1, p less than 0.01). No differences in either biochemical variable were found between hypertensive and normotensive diabetic patients at the end of the study. The results suggest that both serum NAG activity and albuminuria may serve as early functional indicators of diabetic retinopathy.

Acetylglucosaminidase↗
PubMed1991

Phosphate kinetics in dialysis patients.

During extrarenal therapy, plasma phosphate concentrations have specific kinetics: plasma values reach a steady-state nadir 90-120 min after the beginning of the session (from 0.6 to 1.1 mmol/l) with a subsequent high rebound in the 3-4 h following the session. These kinetics are found during haemofiltration (HF) with high ultrafiltration (UF) rates (greater than 270 ml/min) and UF volumes (greater than 30 1). Other HF studies with different UF rates (100 or 200 ml/min) show that delayed mass transfer cannot explain kinetics which result from a phosphate transfer from cellular to extracellular space. Acetate or bicarbonate reinjection fluid does not modify phosphate kinetics. Immediate decrease of ionised calcium after the session argues against a mobilisation from the exchangeable phosphate pool of bone. Only potassium shows a similar pattern to phosphate, so the hypothesis of a relation between cellular phosphate and potassium fluxes is postulated. 31P-NMR study during and after HF does not allow us to specify phosphate transfer from the cell, but various potassium concentrations in the reinjection fluid (0, 2, 3.5, or 4 mmol/l) confirm the influence of potassium removal on phosphate transfer, and a significant linear relationship can be established between cellular potassium and phosphate fluxes. The influence of phosphate removal on phosphataemia has also been investigated using 0, 2, or 3 mmol/l phosphate in the reinjection fluid. Whatever the phosphate modification achieved by the session, the patient's phosphate concentrations are not significantly different 2 days later.(ABSTRACT TRUNCATED AT 250 WORDS)

Hemofiltration↗
PubMed1990

[Factors affecting normal levels of insulin, cortisol, STH, thyroxine and triiodothyronine].

Published "normal" values of some hormones have an excessively wide range and unequal mean values because the material on which these values are based is from subjects suffering from different diseases which only apparently are not associated with the investigated hormone, or else the specimens are obtained under non-standard conditions (malnutrition, stress, alcohol etc.). This wide range of normal values may hide incipient pathological processes and is not suitable even as control group. The investigation is based on the assessment of insulin, growth hormone (GH), cortisol, thyroxine (T4) and triiodothyronine (T3) in a group of blood donors. The assembled results were compared with two other groups of blood donors and a group of obese subjects. The following findings were assembled: We recommend to lower the upper borderline of "normal" insulinaemia from the recommended value of 26 to 20 i.u./l, as the original range may comprise milder forms of hyperinsulinism which is recently assumed to participate in the genesis of type 2 diabetes, hypertension, coronary ischemia and polycystic ovaries. Elevated normal values of serum insulin may be obtained also from blood donors who usually have breakfast before the blood is collected. The wide range of cortisolaemia is due to the diurnal rhythm. The basal value is raised by a declining blood sugar level, alcohol, obesity and of course, varying forms of stress. The upper range of cortisolaemia at 8 a.m. should not be beyond the range of 140-690 nmol/l. GH secretion is governed by an individual 3.5-hour cycle as well as changes of the blood sugar level, e. g. during the OGTT: the declining blood sugar level raises the GH level.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[The relation of flow velocity in the carotid vessels to age].

Using continual Doppler sonography, the authors measured the highest systolic blood flow rate in the extracranial carotid bloodstream in 3 groups of non-cardiac patients of an average age of 22, 76 and 93 years. In each group, the arteria carotis communis showed, with increasing age, a decrease in the highest systolic rate: 0.692 +/- 0.084 - 0.414 +/- 0.073 - 0.297 +/- 0.031 m/s (p less than 0.01 in all the three groups). Equally, a decrease in the highest systolic rate was found in the arteria carotis interna: 0.506 +/- 0.071 - 0.298 +/- 0.064 - 0.211 +/- 0.10 m/s (p less than 0.01 in all 3 groups). The paper shows a statistically significant decrease in the systolic blood rate in the carotid bloodstream related to aging (p less than 0.01) and discusses causes of this phenomenon.

Adolescent↗
PubMed1985

Technical and clinical data on high-performance hemofiltration: twelve patients during one year.

In 12 chronic hemodialysis patients, postdilutional hemofiltration (HF) was substituted for conventional acetate hemodialysis (HD) (4-5 h/session with high-area capillary dialyzers). In HF, the purposes were to obtain (a) no increase in pre-HF uremia compared with pre-HD uremia (high ultrafiltrate volume), (b) an HF duration shorter than that of HD (mean ultrafiltrate rate greater than 120 ml/min), (c) a disposable cost of an HF session identical to that of an HD session (reuse of hemofilters and extemporaneous preparation of substitution fluid). One-year results were (a) an ultrafiltrate volume of 26.8 L/session and a pre-HF uremia of 35.4 mmol/L (pre-HD uremia 34.0 mmol/L), (b) a mean ultrafiltrate rate of 143 ml/min and a mean HF duration of 190 min (mean HD session duration 250 min), and (c) better clinical tolerance and vascular stability in HF than in HD (weight loss 3.5 kg in HF and 3.0 kg in HD). Reuse of filters and extemporaneous preparation of substitution fluid were not responsible for any pyrogen reaction or bacterial contamination. In conclusion, (a) compared with conventional HD, high-flux HF results included identical removal of small molecules, improvement in vascular stability, decrease in session duration, and identical disposable cost; (b) routine high-flux HF is workable in a dialysis unit; (c) vascular access is the most important limiting factor to high-flux HF. Today 30-40% of patients can be treated with this method.

Adult↗
PubMed1983

Plasma kinetics of small molecules during and after hemofiltration: decrease in hemofiltration efficiency related to increase in ultrafiltration rate.

The influence of delay in mass transfer on the real efficiency of hemofiltration sessions (HF) was studied in 7 patients during HF at a moderate ultrafiltration rate (UF rate = 100 ml/min) and at a high UF rate (UF rate = 200 ml/min). Real efficiency was expressed as "effective clearance" (KE) and compared to plasma clearance (KP); KE/KP was calculated from the kinetics of small molecules during HF and stabilized rebound post HF. Rebound in urea and uric acid plasma levels stabilized by 90 min post HF; increase in the UF rate from 100 to 200 ml/min was responsible for a decrease in KE/KP of 4% for urea and 11% for uric acid. Plasma creatinine and phosphorus levels had not stabilized by 90 min post HF, and it was thus impossible to calculate effective clearance; on the other hand, the magnitude of the rebound phenomenon for these two molecules was considerably greater than for uric acid. The magnitude of the post HF rebound for creatinine and phosphorus might be associated with delayed diffusion from a bound form in the intracellular space.

Blood↗
PubMed1982

Degradation of glucagon receptors by dispase treatment of isolated intact rat hepatocytes.

Collagenase-isolated rat hepatocytes were treated with dispase II, a neutral proteolytic enzyme which is often used for the disintegration of neonatal cells. The treatment of hepatocytes with dispase II caused a significant reduction of glucagon binding to the intact cells. The deleterious effect of this enzyme on the specific glucagon binding site is accompanied by a reduction of the maximum intracellular cyclic AMP production.

Animals↗
PubMed1981

Hepatotoxic effects of sera from patients with fulminant hepatitis B on isolated rat hepatocytes in culture.

The hepatotoxicity of sera from patients with terminal fulminant hepatic failure has been investigated by cell culture techniques. It could be shown that both untreated and heat-treated sera are cytotoxic in nature. Compared with the action of sera from healthy individuals on liver cells in primary monolayer culture, the pathological sera exhibited significantly different behaviour with respect to morphological and biochemical parameters such as cell adhesion, growth and proliferation, and enzyme release.

Alanine Transaminase↗