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T Haas

Publications and source records attributed to T Haas.

12 recordsLinked to original sources

[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

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

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

[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

[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

[Lung embolism].

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Humans

Mortality among United States Coast Guard marine inspectors.

Work history records and fitness reports were obtained for 1,767 marine inspectors of the U.S. Coast Guard between 1942 and 1970 and for a comparison group of 1,914 officers who had never been marine inspectors. Potential exposure to chemicals was assessed by one of the authors (RP), who is knowledgeable about marine inspection duties. Marine inspectors and noninspectors had a deficit in overall mortality compared to that expected from the general U.S. population (standardized mortality ratios [SMRs = 79 and 63, respectively]). Deficits occurred for most major causes of death, including infectious and parasitic diseases, digestive and urinary systems, and accidents. Marine inspectors had excesses of cirrhosis of the liver (SMR = 136) and motor vehicle accidents (SMR = 107), and cancers of the lymphatic and hematopoietic system (SMR = 157), whereas noninspectors had deficits for these causes of death. Comparison of mortality rates directly adjusted to the age distribution of the inspectors and noninspectors combined also demonstrated that mortality for these causes of death was greater among inspectors than noninspectors (directly adjusted ratio ratios of 190, 145, and 198) for cirrhosis of the liver, motor vehicle accidents, and lymphatic and hematopoietic system cancer, respectively. The SMRs rose with increasing probability of exposure to chemicals for motor vehicle accidents, cirrhosis of the liver, liver cancer, and leukemia, which suggests that contact with chemicals during inspection of merchant vessels may be involved in the development of these diseases among marine inspectors.

Accidents, Traffic