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A Hesse

Publications and source records attributed to A Hesse.

At least 19 recordsLinked to original sources
PubMed1995

Influence of a mixed and a vegetarian diet on urinary magnesium excretion and concentration.

Urinary Mg is suggested to be an effective inhibitor of the formation and growth of calcium oxalate stones. In order to examine the influence of variations in dietary Mg on urinary Mg excretion, ten healthy male subjects were kept on two different standard diets for 5 d each. In the course of the test period, 24 h urine samples were collected. Diets 1 and 2 were calculated according to the dietary recommendations of the German Society of Nutrition (Deutsche Gesellschaft für Ernährung, 1986). Diet 1 was established as a model of a balanced mixed diet, whereas diet 2 represented an ovo-lacto-vegetarian meal plan. Diets 1 and 2 were isoenergetic with equal amounts of the main nutrients, estimated from food tables, and a constant fluid intake. In contrast to the content of Mg (336 mg) and dietary fibre (28 g) of diet 1, diet 2 was rich in Mg (553 mg) and dietary fibre (52 g). On the ingestion of diet 1, renal Mg excretion was 5.09 (SEM 0.35) mmol on the control day and increased slightly but not significantly to 5.40 (SEM 0.52) mmol on the corresponding day on diet 2. Urinary Mg excretion as a percentage of estimated dietary intake was about double on the balanced mixed diet (37%) than on the Mg-rich vegetarian diet (24%). As both diets contained equal amounts of most nutrients, these results indicate a lower excretion rate of Mg from the vegetarian diet than from the mixed diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

When is the indication of percutaneous chemolysis justified?

Persistent residual stone fragments after extracorporeal shockwave lithotripsy (ESWL), percutaneous nephrolitholapaxy (PNL) as well as pyelo- and nephrolithotomy represent a great problem in the treatment of stones. The choice of therapy for patients with insufficient renal drainage, poor renal function, and a high anesthetic risk also remains quite difficult. Between 1991 and 1993, 5 patients underwent percutaneous antegrading chemolysis with 'Suby G' solution. Two patients, presenting struvite and apatite stones, were free of stones afterwards. In 1 patient, where stone size could be observed. In 2 other brushite component, a large decrease in stone size could be observed. In 2 other cases, with stones mainly consisting of whewellite and weddelite, chemolysis proved ineffective. Evaluating our own clinical experience and relevant medical literature, the present study goes on to prove that the indication of percutaneous chemolysis in risk patients as described above is dependent on stone analysis, and must be regarded as an effective adjuvant treatment.

Adult↗
PubMed1994

[3-D ultrasound--data acquisition and representation].

A three-dimensional (3D) workstation for data acquisition, processing, registration and presentation of 3D ultrasound information is described. The ultrasound images needed for further processing are generated by a standard diagnostic ultrasound system. The 3D transducers used here include frequencies of 3.5, 5 and 7.5 MHz. The presentation of reconstructed 3D data is performed by computer-assisted projection of volumetric data or by the presentation of user-selectable slices from the 3D object. Besides improved diagnosis of 3D structures, the system enables precise volume measurements.

Computer Systems↗
PubMed1993

Urinary saturation and nephrocalcinosis in preterm infants: effect of parenteral nutrition.

Urinary lithogenic and inhibitory factors were studied in 27 preterm infants; 16 had total parenteral nutrition (TPN) and 11 had breastmilk with an additional glucose-sodium chloride infusion. Urines were collected for 24 hours on day 2 (period A), day 3 (B), and once between days 4 and 10 (C). Urinary calcium oxalate saturation was calculated by the computer program EQUIL 2. Renal ultrasonography was performed every second week until discharge. The calcium/creatinine ratio increased in infants on TPN (A 0.91; C 1.68 mol/mol) and was significantly higher at period C than that in infants on breastmilk/infusion (A 0.52; C 0.36). The oxalate/creatinine ratio was persistently higher with TPN (203 mmol/mol) than with breastmilk/infusion (98; 137). The citrate/creatinine remained constant with TPN (0.44 mol/mol), whereas it increased significantly with breastmilk/infusion (0.26; 0.49). Calcium/citrate rose considerably with TPN, but decreased with breastmilk/infusion to a significantly lower level than with TPN. The urinary calcium oxalate saturation increased with TPN (2.4; 4.5) and decreased with breastmilk/infusion (2.1; 1.5) to a significantly lower value than with TPN. Nephrocalcinosis developed in two infants on TPN. Mean daily calcium intake was similar in both groups, whereas protein, sodium, and phosphorus intake were significantly higher on TPN. It is concluded that the increase in urinary calcium oxalate saturation observed with TPN is due to the combined effect of an increased urinary calcium excretion and higher urinary oxalate/creatinine and calcium/citrate ratios. The changes observed are likely to be caused by TPN itself, which differs in several respects from breastmilk feeding.

Breast Feeding↗
PubMed1993

Cardiac amyloidosis: a review and report of a new transthyretin (prealbumin) variant.

Cardiac amyloidosis is caused by amyloid deposits derived from different human plasma proteins. It can lead to cardiac conduction disturbances, restrictive cardiomyopathy, and low output heart failure. The heart is variably involved during the development of systemic amyloidosis and seems to be more frequently affected in immunoglobulin (primary) than in reactive (secondary) amyloidosis. Amyloid is common in the elderly. Isolated atrial amyloid, for which a major subunit is the atrial natriuretic peptide, seems to be three times more frequent than senile cardiac amyloid, which is derived from normal prealbumin (transthyretin). Like polyneuropathy, cardiac amyloidosis is a prominent clinical feature of hereditary amyloidosis, namely of the autosomal dominant transthyretin (TTR) type. All 28 cases of TTR amyloidoses reported so far were heterozygotes for a single nucleotide change in the gene for TTR that resulted in amino acid substitutions in the mature protein. A new TTR genetic variant is reported in a German family where the index patient presented at the age of 63 with anginal pain and arrhythmia. Electrocardiography was suggestive of a pseudoinfarction pattern, and echocardiography and cardiac catheterisation showed signs of hypertrophic nonobstructive cardiomyopathy with increased ventricular filling pressures and a prominent "a" wave. Amyloid of the TTR type was identified by immunohistochemistry in the endomyocardial biopsy specimen. Hybrid isoelectric focusing established heterozygosity by showing normal TTR protein and an electrically neutral TTR variant differing from all known TTR variants so far. The patient died in an accident before investigations were complete. Electrophoretic analysis of the plasma from his first degree relatives (son, daughter, brother, and mother) identified the asymptomatic 22 year old son as an apparently heterozygous carrier of the mutant TTR protein. Comparative tryptic peptide mapping and sequencing showed that isoleucine at position 68 of the amino acid sequence was replaced by leucine.

Amino Acid Sequence↗
PubMed1993

Scanning electron microscopy of 2,8-dihydroxyadenine crystals and stones.

The lack of purine salvage enzyme, adenine phosphoribosyltransferase (APRT), leads to 2,8-dihydroxyadenine stone formation and/or crystalluria because it is insoluble in urine. Urolithiasis composed of 2,8-dihydroxyadenine is not only formed in a complete defect of APRT, but also in a partial deficiency of this enzyme. The defect is inherited as an autosomal recessive trait, the homozygous state is associated with high urinary levels of 2,8-dihydroxyadenine and with crystalluria, calculus formation, and potential nephrotoxicity. Determination of the APRT activity will facilitate quantification of the enzyme deficiency and elucidation of the hereditary history. 2,8-dihydroxyadenine excretion in the 24-hour urine and its circadian rhythm were determined using a new method of high performance liquid chromatography determination. By means of a standard case presentation, we illustrate the analysis of urinary sediments and calculi as well as the scanning electron microscopic images of this kind of stone.

Adenine↗
PubMed1993

The influence of dietary factors on the risk of urinary stone formation.

The action of various beverages and foods on the composition of the urine in the circadian rhythm and in the 24-hour urine has been investigated under standardized conditions. Orange juice leads to a significant increase of urinary pH and citric acid excretion. Black tea leads to a raised excretion of oxalic acid by only 7.9%. In the short term, beer increases diuresis, but afterwards leads to a compensatory antidiuresis with increased risk of stone formation. Depending on their composition, mineral waters have very different effects on the urinary constituents. Milk as well as cocoa beverage significantly increase calcium excretion; moreover, cocoa causes an increase in the oxalic acid excretion. The leafy vegetable foods containing oxalate, e.g., spinach and rhubarb, lead to peaks of oxalate excretion of 300-400% in the circadian excretion curve. Cheese leads to a significant rise of calcium excretion with acidification of the urine and lowering of citrate excretion. Calcium excretion is increased by 30% by sodium chloride. Foods containing purine result in an increased uric acid excretion over several days. Depending on their phytic acid content, brans bind calcium, but lead to an increased oxalic acid excretion. Analysis of the urine indicates that average diet in Germany entails a high risk of urinary stone formation. As a result of the change to a balanced mixed or vegetarian diet, according to the requirements, significant alterations in urinary pH, calcium, magnesium, uric acid, citric acid, cystine, and glycosaminoglycan excretion are measured, resulting in a drastic reduction in the risk of urinary stone formation.

Adult↗
PubMed1993

[The infection risk for dogs raised helminth-free in conventional conditions in an urban area].

The present investigations were carried out to clarify whether or not and to what extent helminth-free raised dogs acquire patent and impatent helminth infections when exposed to an urban area contaminated with dog faeces. Groups of each 3 bitches at an age of 3, 6 or 9 months were taken out to an urban area (with average dog density of 1.5 per ha) for 3 hours daily on 5 days per week for a period of 3 month. During the whole trial the bitches and puppies born during this period were maintained under conditions which excluded other infections than those acquired during exposure in the urban area. The examination of the animals had the following results: All 9 bitches remained coproscopically negative until the end of the trial. In these bitches neither intestinal stages nor somatic helminth larvae were found. Seven out of 45 puppies from these bitches shed Toxocara canis eggs with the faeces. Shedding of eggs began 21 to 28 days after birth. Eggs excretion in most cases was low (< 33 eggs per gram). In 12 puppies from 5 litters intestinal stages of T. canis were found with a maximum of 4 specimens per animal. In 9 puppies only male or female T. canis were found.

Animals↗
PubMed1992

Dietary fibre: the effectiveness of a high bran intake in reducing renal calcium excretion.

Fifteen healthy women were given a standardized calcium-rich diet (1800 mg calcium/day) with or without 36 g bran for 5 days. A similar study was also carried out with rice, soy and wheat bran. Urine samples were also collected 24 h. With all brans renal calcium excretion decreased and renal oxalic acid excretion increased. However, influence of rice bran was statistically significant. After 5 days of consuming 36 g rice bran/day 14 of 15 subjects showed decreased calcium excretion, but increased oxalic acid excretion. Relative supersaturation with calcium oxalate, as a measure for the risk of calcium stone formation, increased after addition of all brans.

Adult↗
PubMed1992

In vitro investigations into the formation and dissolution of infection-induced catheter encrustations.

Encrustations are the most frequent complications occurring with indwelling catheters and urine drainage systems. The conditions for bacterial infections, using synthetic urine and controlled contamination by Proteus vulgaris, were standardised by using an in vitro model. Crystal deposits on catheters were analysed by infra-red spectroscopy and scanning electron microscopy. The main components of deposits in all investigations were struvite (MgNH4PO4.6H2O) 60-70% and carbonate apatite (Ca10(PO4,CO3)6 (OH,CO3)2) 30-40%. Investigations as to the quality and quantity of encrustations confirmed the analysis. Irrigation treatment was carried out with physiological saline solution and citric acid solution (Suby G) to study and quantify the dissolution of crystal deposits. Regular irrigation with citric solution resulted in a 70% dissolution of encrustations and ensured free flow as ascertained by measuring flow rates.

Animals↗
PubMed1991

High-performance liquid chromatographic determination of urinary cysteine and cystine.

A method for quantitative determination of cystine and its monomer, cysteine, is presented using reversed phase HPLC with precolumn derivatization by ophthaldialdehyde (OPA). The new application exhibits a two step procedure for overcoming the minimal fluorescence of the OPA-derivatives of cysteine and cystine: after reduction of cystine to cysteine by dithiothreitol the sulfhydryl-group of cysteine is blocked with iodoacetic acid. Optimum reaction conditions of this derivatization procedure are described. Special precautions relating to the rather fast oxidation of cysteine are necessary. Collecting urine directly into sulphosalicylic acid prevents oxidation of cysteine up to 5 days. Initial results of urinary concentration of cysteine and cystine of healthy control persons and patients suffering from cystinuria are presented.

Chromatography, High Pressure Liquid↗
PubMed1991

Investigations of the efficacy of ascorbic acid therapy in cystinuria.

We investigated ascorbic acid therapy for cystinuria in a study of seven healthy control persons and seven cystinuric patients. The study lasted 9 days. During the first period, we collected 24-h urine specimens from all subjects on 3 consecutive days. Starting on day 4, all were given 5 g ascorbic acid/day for a period of 6 days. On the last 3 days, 24-h urine specimens were again collected. Quantitative amino acid determination was performed using an HPLC method described elsewhere. During ingestion of ascorbic acid, the mean excretion of cysteine by the control group increased from 134.1 to 159 mumol/day, whereas the excretion of cystine decreased from 107.1 to 82 mumol/day. The corresponding values for the cystinuric patients increased from 352.4 to 452.1 mumol/day for cysteine and decreased from 4,131.6 to 3,663.2 mumol/day for cystine. Thus, ascorbic acid seems to have only mild reducing properties in respect to cystine.

Ascorbic Acid↗
PubMed1991

Significance of glycosaminoglycans for the formation of calcium oxalate stones.

Glycosaminoglycans (GAG) are polysaccharide chains composed of repeating disaccharides of identical composition. Little is known about the mechanism of their excretion, but there is no doubt that urinary GAGs are degradation products of high molecular weight proteoglycans. Renal excretion takes place chiefly as glomerular filtration, and tubular reabsorption or secretion has not been demonstrated. Differences in the literature comparing GAG excretion in urolithiasis patients and healthy subjects are mainly attributable to methods of analysis and noncomparability of the investigation conditions. We found no differences between the two groups in several series. It is interesting to note that GAG excretion in men is significantly higher than in women, that a circadian rhythm of GAG concentration and excretion occurs in healthy subjects on a standardized diet, and that values are raised postprandially and at night. Seasonal course of GAG excretion curves is almost synchronous for men and women, irrespective of the absolute values, and GAG excretion in the spring and summer significantly exceeds that in winter months by up to 50%. All crystallization models cited demonstrate that GAG reduce the risk of calcium oxalate stone formation. Inhibitors of crystal growth and aggregation act by blocking the growth sites. Inhibition of calcium oxalate crystallization is also attributed to direct binding of calcium to GAG. In the presence of urate ions, and favorable pH, the ability of chondroitin sulfate C to bind calcium may be impaired by as much as 31%. These measurements support the concept that urate ions interact with GAG in urine.(ABSTRACT TRUNCATED AT 250 WORDS)

Calcium Oxalate↗