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Biomedical subjects

H J Graubaum

Publications and source records attributed to H J Graubaum.

At least 19 recordsLinked to original sources

Early urinary markers of target nephron segments as studied in cadmium toxicity.

A number of chemicals may adversely affect one or more of the anatomical structures of the kidney, such as the glomerulus, the tubular apparatus, the medullary, or interstitial cells. To recognize subclinical renal dysfunction, a battery of new, non-invasive tests was applied in comparison to established ones. The study on cadmium exposed subjects, performed within the framework of a collaborative European research project, exemplifies the concept of target selectivity within a nephron. One hundred seventy-two subjects were classified according to urinary cadmium excretion as controls (< 1.5 micrograms/g creatinine), or subjects with moderate or high cadmium body burden (1.5 to 5 micrograms/g creatinine, > 5 micrograms/g creatinine). Twenty-six urinary analytes (such as serum derived proteins, tubular enzymes, eicosanoids) and four plasma markers, related to the function or integrity of specific nephron segments, were investigated in a cross-sectional study. The group with the moderate cadmium body burden showed alterations of proximal tubular integrity, that is, increased excretion of tubular brush-border antigens. The group with higher cadmium body burden revealed an involvement of the whole nephron. The most prominent quantitative changes were found for the glomerular markers high molecular weight proteins, and thromboxane B2 and for the proximal tubular markers retinol binding protein, alpha 1-microglobulin, N-acetyl-beta-D-glucosaminidase, and the intestinal alkaline phosphatase. A diagnostic approach to screen for nephrotoxicity due to environmental hazards like cadmium should include proximal tubular markers (alpha 1-microglobulin and tubular enzymes, that is, intestinal alkaline phosphatase) but the measurement of glomerular markers is also advisable.

Adult

Urinary proteins and enzymes as early indicators of renal dysfunction in chronic exposure to cadmium.

We tested the diagnostic sensitivity of various urinary analytes for detecting cadmium-induced nephropathy at an early stage. We investigated 73 healthy persons (control group 1) and individuals exposed to cadmium, either environmentally (n = 36, risk group 2) or occupationally (n = 62, exposed group 3). All data were related to limits of the central 95% reference intervals of the control group. The serum creatinine and ribonuclease values, indicators of the glomerular filtration rate, were not different in the three groups. In the exposed persons (group 3), proximal tubular indicators (low-M(r) proteins lysozyme, ribonuclease, retinol-binding protein, and alpha 1-microglobulin) were more often increased than the glomerular indices (higher-M(r) proteins transferrin, IgG, and albumin). Both the low-M(r) proteins and tubular enzymes were differently altered in their excretion rates. Alanine aminopeptidase, alkaline phosphatase, and N-acetyl-beta-D-glucosaminidase increased even in the risk group 2. alpha 1-Microglobulin was increased in the exposed persons whose cadmium excretion was < 5 mumol/mol creatinine. The combined determination of alpha 1-microglobulin and N-acetyl-beta-D-glucosaminidase exceeded the corresponding upper reference limits in 30% of group 2 and 39% of group 3. We recommend screening for these two analytes to detect cadmium-induced renal dysfunction at an early stage.

Acetylglucosaminidase

[Use of the stable nitrogen isotope 15N in assessing liver metabolism in hormonal contraception].

In 37 women with long-term use of oral contraceptives (average use 13.4 years) and 12 women who had not taken oral contraceptives for at least 5 years we determined the serum enzymes ALAT, ASAT, Gamma-GT and conducted the 15N-ammonium test as a marker of partial metabolic performance of the liver. In addition we studied total protein, protein fractions in the serum and haematologic parameter. 18 out of 37 women showed a morbid result in the 15N-ammonium test. In 4 of these 18 women morphological changes representing hepatic damage caused by contraceptives could be detected. On the average ALAT, Gamma-GT and 15N-ammonium test in both groups are clearly different. Because the enzymic levels are being in the normal range, only the 15N ammonium test enables to give a hepatotoxic evidence. It is possible to conclude that long-term use of oral contraceptives influences the liver metabolism.

Adult

[Biochemical studies of the assessment of transplant function following clinical heart transplantation--initial experiences].

Average and specific individual courses of the following parameters are reported in this paper, with reference being made to eight of eleven clinical heart transplantations so far performed at the authors' department: lactate, pyruvate, myoglobin, ASAT, ALAT, GGT, CK, CK-MB, LDH, LDH-1, and glycogen phosphorylase. Glycogen phosphorylase was found to deviate most strongly from normal, with the enzyme exhibiting two initial maxima. The enzyme activity in the serum vanished not later than twelve days from transplantation. The curve of myoglobin was largely parallel to that of phosphorylase. Phosphorylase seemed to be of particular suitability for assessment of ischaemic damage in the wake of transplantation. The individual courses seemed to suggest that none of the investigated parameters exhibited sufficiently sensitive correlations with pathomorphological signs of rejection.

Adult

[Physical exertion and the course of hepatitis].

Twenty-five patients with clinically and histologically verified acute hepatitis were subjected to a submaximal bicycle ergometer exercise during the first week after inpatient admission and afterwards subdivided into two groups. The first group maintained bedrest, and the other group trained for 30 minutes a day over six weeks at an exercise level amounting to 70% of the submaximal performance of the initial ergometry. Histological, clinical and laboratory results did not differ between the groups. It is concluded that immobilization for a short time only is indicated in acute hepatitis.

Acute Disease

[Value of various amino acid mixtures for the treatment of chronic liver damage].

A reproducible liver lesion was caused in 28 pigs by intermittent, intraperitoneal administration of thioacetamide. The morphological degree of the liver lesion was checked by histological investigations (material drawn from the liver by biopsy). During a 3-day infusion period a so-called liver solution (Aminofusin hepar) was given to one group of animals, a normal solution (Infesol) to a second group, and only an electrolyte infusion solution under oral nutrition ad libitum to a third one. The solutions were labelled with (15N) glycine. The amounts of total N, total 15N, 15N with single non-protein fractions, a number of enzymes of 15N incorporated into the liver protein were measured in urine, and the following points were established: 1. The catabolic situation of metabolism is eliminated both by the so-called normal solution and the specific amino acid solution. The two mixtures of L-amino acids thus have a nutritive effect. 2. The toxic liver lesion is an indication for parenteral nutrition. Oral nutrition alone is not sufficient. 3. The so-called liver solution influences the liver metabolism of the protracted liver lesion more than the so-called normal solution does, and considerably more than an electrolyte infusion solution under oral nutrition ad libitum.

Amino Acids

[Liver diagnostics].

Prerequisite of a scientific and rational liver diagnostics is the knowledge of the physician of function and structure of the liver. The laboratory demand should always be an accomplishment of the physician and should be performed only upon such a scale that it is also followed by therapeutic consequences and/or consequences concerning the expert's opinion. The biochemical blood analysis gives information about the size of the injury to the parenchyma and about the disturbance of the various partial functions of the liver. In this case is to be taken into consideration that biochemical and histological parameters are no concurrent, but supplementing diagnostic methods. A progress in liver diagnostics is the use of the isoenzymes of the aspartate aminotransferase and the lactate dehydrogenase as well as of the enzymes of the metabolism of the connective tissue. With the entering into selected parameters of the liver diagnostics possibilities to the establishment of the disturbed liver metabolism by means of markers are shown and at the same time recommendations for the praxis of the liver diagnostics are derived.

Clinical Enzyme Tests

[Acute viral hepatitis and body loading--a self-excluding therapeutic principle?].

Of 27 patients with acute virus hepatitis 16 patients performed successfully a daily training programme during their stay in hospital. On the basis of both clinical and clinical chemical parameters in comparison to the control group of 10 patients who observed the conventional rest in bed the course of healing did not deteriorate. Also with regard to the late prognosis no higher rate of recidivation or chronification could be proved. Our examinations support the thesis that the demand of strong rest in bed is to be regarded as out of date in the treatment of acute virus hepatitis.

Adult

[Significance of isoenzymes in acute hepatitis and differential diagnosis of chronic forms of hepatitis].

By the determination of the aldolase, GOT and LDH isoenzymes in the plasma the stage of the acute and chronic hepatitis can be well established. The suitable use of modern statistic methods (multivariate analysis) allows the characterisation, recognition and separation of the groups of disease acute, chronic persisting, chronic aggressive hepatitis and liver cirrhosis as well as the proof of transition forms and severe courses. In acute hepatitides with protracted course under prednisolone therapy in contrast to histology already after a short time changes of the isoenzymes in the hepatic tissue and in the plasma are shown. Apparently the isoenzymes are sensitive indicators of intracellular metabolic processes.

Acute Disease

[Significance of isoenzymes for the prognostic evaluation of acute hepatitis--studies under load].

100 patients who got over a virus hepatitis underwent a bicycle ergometry. At the beginning and at the end of the experiment as well as 24 hours after this the isoenzymes of aldolase, GOT and LDH in the plasma were determined by means of kinetic methods. On the basis of the activities of the isoenzymes for the test persons (children and adults of either sex) an arrangement in the groups pathologic--suspicious--normal can be carried out which is compared with the physiologic parameters and the clinic. The results of bicycle ergometry much differ. High effects without pathological changes of the activities of isoenzymes are an objective criterion of the quick, riskless rehabilitation of the test persons.

Acute Disease