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W Berg

Publications and source records attributed to W Berg.

At least 91 records · Page 5Linked to original sources
PubMed1980

[Calcium oxalate activity products and discriminant analysis of urinary parameters as basis for a calcium oxalate screening program (author's transl)].

The values of 7 urinary parameters in divided urine collections were measured in 20 patients with calcium oxalate stones and ten normal persons. On this basis the thermodynamic stone formation risk was calculated for the different urine collections. Stone formation risk in the 0-6 a.m. urine fractions appeared to be the most important. The risk of stone formation is significantly increased in the time from midnight to 6 a.m. To detect the risk situation the determination of oxalic acid, calcium, potassium and inorganic sulfate in night urine is adequate.

Calcium↗
PubMed1979

The isoelectric point of thrombin and its behaviour compared to prothrombin at some solid surfaces.

We have shown that the isoelectric point of thrombin is high and that thrombin is a cation at the pH of blood. On the other hand, prothrombin has a low isoelectric point, being more anionic at the pH of blood. It was also found that thrombin adsorbs readily to surfaces, especially negatively charged surfaces, like behenic acid surfaces at pH 8.2. Furthermore, thrombin adsorbed onto behenic acid was active in the sense that it coagulated fibrinogen. The significance of the electric charge of the thrombin molecule in the mechanism of atherosclerosis is discussed.

Adsorption↗
PubMed1979

A contribution to the formation mechanism of calcium oxalate urinary calculi. IV. Experimental investigations of the intrarenal crystallisation of calcium oxalate in rabbit.

Rabbits were given glyoxylic acid to induce intrarenal calcium oxalate crystal formation. The point of crystallisation in the renal tubule, the structure and the composition of the intrarenal crystals were studied. The initial crystallisation takes place in the proximal tubule. Calcium phosphate formation was excluded by microprobe examination. The comparison of the structures of the intrarenally formed crystals with those of Whewellite stones by scanning electron microscopy and the examination of isolated crystals by x-ray diffraction showed the intratubular crystals to consist of Whewellite.

Animals↗
PubMed1979

Scanning electron microscope and microprobe investigation of phosphate phases in uroliths.

In uroliths various phosphate phases can be detected which indicate different formation conditions. Structure and topography of the respective phosphate phases are characterized by scanning electron microscopy and microprobe techniques. Trace element enrichment is investigated and illustrated; for example, sulfur is found preferentially in carbonate apatite. From the distribution of the phosphate phases, conclusions can be drawn concerning the urolith genesis.

Crystallography↗
PubMed1979

[Investigations on formation risk of calcium oxalate stones with special regard to stress (author's transl)].

Concentrations and excretion of ten urine parameters were recorded in defined urine portions of 20 calcium oxalate stone patients and 10 normal subjects; some of these urine constituents show a day-night rhythm thus indicating a daily risk variation. From the analysis of questionnaires on physical strain and psychonervous stress, correlations between stress and urine substances can be established. In this connection, oxalic acid concentration and excretion seem to be of special importance. The obtained results provide the basis for further complex-chemical calculations.

Adult↗
PubMed1979

Submicroscopic investigations on calcium oxalate stone genesis.

Scanning electron microscopy of calcium oxalate stones indicates a zonary structure of the Weddellite crystals of urine concrements which is due to concentration-dependent growth oscillations representing the precipitation of various calcium oxalate hydrates. In addition to the phenomenological demonstration of Weddellite crystal shapes, incubation experiments with different solutions give rise to the postulation of a dehydration process of primary Weddellite crystals via dissolution and recrystallization to Whewellite. The solvent attack starts at energetically preferred corners, edges and lattice disorders of the Weddellite crystals. The Weddellite-stabilizing role of urinary Mg ions is emphasized.

Calcium Oxalate↗
PubMed1979

[Effect of drugs used for the prevention of urinary calculi recurrence on the growth and metabolism of young experimental animals].

In the animal experiment should be made clear whether several medicaments which stood the test in the prevention of relapses of urinary calculi may be used without any danger also in the infantile carrier of concrements. For this purpose young rabbits high doses of diuretics, kation exchangers, aluminium oxide, extracts of the root of rubia tinctorum, succinimide and diphosphonate were given. Growth and development of the animals were negatively influenced by the medicaments, with the exception of the kation exchanger and the extracts of the root of rubia tinctorum. Numerous animals died under the administration of duiretics. The results of the examinations of metabolism only partly allow general conclusions. The medicamentous long-term metaphylaxis of the urolithiasis in childhood is also to be used like dietetic restrictions under strong indication and permanent control.

Aluminum Oxide↗
PubMed1979

[A modified method for the quantitative determination of urinary oxalic acid].

The present paper describes a modified method of the quantitative determination of oxalic acid in the urine which is based on the reduction of oxalic acid to glycolic acid and on the transformation with chromotropic acid to a colorimetrically well measurable complex of colours. The method ascertains a good reproducibility and is simply to be performed in every clinico-chemical laboratory.

Colorimetry↗
PubMed1979

[Pseudomorphoses in calcium oxalate urinary calculi].

Pseudomorphoses of whewellite to weddellite reflect on transparent section preparations and in the REM appearances of cristallisation processes in the secondary whewellite formation via weddellite dehydration. As transformation products are found fine-grained polycrystalline as well as due to recrystallisation larger monocrystalline whewellite. An interesting analogy to this gives the thermic dehydration of weddellite crystals in direction to whewellite, which realises under formation of pseudomorphoses as topotactic process. The dissociation scars appearing in this case are strongly oriented to the crystal grid of weddellite.

Calcium Oxalate↗
PubMed1979

[The long-term effect of various hormonal contraceptives on the excretion of sodium, potassium, calcium, magnesium, chloride, phosphorus, uric acid, oxalic acid, citric acid, sulfate and lysozyme in the 24 hour urine].

The influence of a long-term application of 4 different hormonal contraceptives on the excretion of various constituents of the urine was examined. A reverse effect after stoppage of the medication is to be established in none of the other parameters with the exception of calcium.

Calcium↗
PubMed1978

[Copper and zinc in cerebrospinal fluid of children with neurological diseases (author's transl)].

We examined CSF copper and zinc concentrations in 30 children with acute febrile illness and meningism (control group) and in 37 patients with shortlasting seizures, febrile or not, and acute viral meningitis. The trace elements were quantitatively measured by means of atomic absorption spectrophotometry. 1. It was shown that the concentrations of copper and zinc in CSF remain constant during childhood.--2. No increase could be found in the concentrations of copper and zinc in CSF caused by the neurological diseases of our patients. These data suggest that permanent cerebral lesions as a consequence of shortlasting seizures and viral meningitis would be very unlikely and that a transient dysfunction of metabolism does not liberate copper- and zinc-metallo-proteins in CSF. 3. There was no correlation between the protein concentration in CSF and copper and zinc concentrations in CSF.

Adolescent↗
PubMed1977

Mass spectrometric trace element analysis of calcium oxalate uroliths.

Mass spectrometric trace element analysis of whewellite and weddellite uroliths revealed 55 elements, from which 20 could be well assessed quantitatively. The total trace element content in weddellite increased by 77.5% with respect to whewellite, the main portion being made up from Na, P, Mg, and Cl. In physiological conditions weddellite is stabilized by trace elements. The importance of trace element analysis of Si, Al, Sr, Rb, S, F, Cl, and Br in uroliths is indicated.

Calcium↗