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Biomedical subjects

C Kleinknecht

Publications and source records attributed to C Kleinknecht.

At least 73 records · Page 4Linked to original sources
PubMed1982

Importance of proteins in the deterioration of the remnant kidneys, independently of other nutrients.

Several experiments have shown that deterioration of renal parenchyma after reduction of functional mass is affected by the protein content of the diet. The respective role of proteins and that of other nutrients particularly phosphorus which varies with proteins was never clearly separated. Three groups of 9 uremic rats U I, U II, U III, received three diets differing exclusively in their protein content, which was supplied by casein and was respectively 8%, 16% and 32%. Other nutrients were maintained identical, including energy and minerals. Food intake was similar in U I and U II rats and was lower in U III rats. Mortality rate remained closely related to protein intake. Of U III rats, 78% died within 10 weeks and 100% within 15 weeks. Of U II rats, 56% were dead at week 15, and 100% at week 30. Mortality occurred significantly later in U I rats fed the lowest protein diet. Histology of remnant kidneys showed severe glomerular and tubular damage, with no or little calcium deposits despite normal phosphorus diet and frequent hyperphosphoremia. In conclusion, protein intake influences survival by accelerating the renal damage in rats with reduced kidney mass independently of any other nutrient.

Animals↗
PubMed1981

Treatment of the idiopathic nephrotic syndrome.

Most of the paediatric patients presenting with nephrotic syndrome (NS) have a nephrosis (minimal glomerular changes with or without focal lesion NS) and most of them are characterized by a clear-cut steroid response: a complete remission is rapidly obtained with high dose of glucocorticoids. Many of them, however, relapse during or after the treatment's withdrawal. Most often, these patients can be managed for several years with long-term alternate-day steroid therapy. Alkylating agents must be used exclusively when the doses of steroids required result in severe toxicity. In other types of NS (steroid resistant nephrosis, membranous and membranoproliferative glomerulonephritides) the efficiency of drugs is not established. Whatever the cause for the NS, adequate supportive therapy is necessary. The constant aim is to allow the patient a normal physical, school and social activity.

Alkylating Agents↗
PubMed1981

Prolonged renal survival and stunting, with protein-deficient diets in experimental uremia. Reversal of these effects by addition of essential amino acids.

The aim of dietary therapy of chronic renal failure is to reduce uremic symptoms while avoiding malnutrition. The possible toxic effects of the diet on the kidney are rarely taken into consideration. The present experiment compared the long-term effects of three low-protein diets in nephrectomized rats (UI, UII, UIII) and in controls: diet I containing 7.5% protein, diet II containing 7.5% protein + 1% EEAs, and diet III containing 14% protein. Nephrectomized rats gained less weight than corresponding controls. UI rats had a decrease in the rate of length gain as opposed to groups UII and UIII. UI, however, maintained a relatively constant GFR, whereas groups UII and UIII had severe reductions in renal function. There were no significant differences between either UII or UIII rats in terms of growth and survival, despite lower consumption not only of proteins but also of all nutrients in the former group measured in a previous study. Thus semisynthetic diet appeared of little benefit. A diet consistent with both normal growth and preservation of renal function remains to be defined.

Amino Acids, Essential↗
PubMed1980

Plasma and muscle free amino acids in children at the early stages of renal failure.

Plasma and muscle free amino acid analyses have been performed on four groups of children with different levels of renal failure. Mean plasma creatinine of the groups 1 to 4 was respectively 1.3, 2.3, 3.3, and 4.9 mg/100 ml. Significant but different alterations of plasma and muscle amino acid pattern were found in the four groups of patients. In plasma, aspartic acid, citrulline, OH-proline, 1- and 3-methyl histidine were regularly increased, while threonine, valine, phenylalanine, isoleucine, leucine, tryptophane, tyrosine, and tyrosine/phenylalanine ratio were generally decreased. In muscle, glutamine was usually increased and alanine, valine and valine/glycine ratio decreased; significant increase of total amino acid content was only noted in group 4. Some amino acid alterations became worse with renal failure such as 3-methylhistidine increase or tyrosine/phenylalanine decrease, but group 3 patients had the greatest number of individual amino acid alternations. This group of patients also had the highest protein intake. Relationship between growth velocity and muscle amino acid pattern was found, a poor growth rate was associated with an increase of nonessential and essential amino acids with the exception of valine.

Adolescent↗
PubMed1980

Lactogenic and somatotropic binding sites in liver membranes of rats with renal insufficiency.

Binding sites for human GH (hGH) were studied in liver membranes of rats with chronic renal insufficiency (CRI) associated with marked growth retardation. A subtotal nephrectomy was performed in young female rats. One month after the nephrectomy, the animals with a plasma creatinine level 3 times or more that of controls were studied; their mean statural gain was 56% that of controls. The specific binding of [125I]hGH to microsomal membranes of rats with CRI was low (40% that of controls). The number of binding sites rather than the affinity of the binding was affected; both the lactogenic and somatotropic sites were decreased, as judged from the binding of ovine [125I]PRL and bovine [125I]GH. The binding sites of the plasma membranes as well as those of the Golgi fractions, were reduced. In plasma membranes of rats with CRI, the specific binding of glucagon was low, and the specific binding of insulin was elevated; these modifications were associated with a high plasma glucagon level and a decreased insulinemia in rats with CRI, but no modification of plasma GH and PRL levels was found. Thus, the hormone level does not appear to regulate the GH-binding sites in this system. The link between the growth defect and the decreased number of GH-binding sites in the liver membranes of rats with CRI remains to be established.

Animals↗
PubMed1979

Membranous glomerulonephritis and hepatitis B surface antigen in children.

Of 33 children with membranous nephropathy screened for HBs Ag, 14 were found to be HBs Ag carriers, whereas HBs Ag was detected in 3 of 170 and 4 of 100 children with glomerular and nonglomerular kidney diseases, respectively. HBs Ag was often associated with acute hepatitis at onset (five patients) or with elevated transminases values. This high incidence and the prevalence of an unusual subtype (ayw2) suggest a relationship between HBs Ag and the glomerular lesions. Using immunofluorescence, however, HBs Ag could not be detected within the deposits, so that the nature of the relationship cannot be considered as established. The clinical outcome (50% remission), the plasma complement component disturbances, and findings by immunofluorescence did not differ from those observed in children with MGN without detectable HBs Ag.

Adolescent↗
PubMed1979

Effect of various protein diets on growth, renal function, and survival of uremic rats.

The effects on growth, renal function, and survival of three isocaloric diets of various protein content (14, 27, and 37 g/100 g in diets I, II, and III, respectively) were compared in uremic rats and in controls. Diet I provided the minimal requirements in all amino acids for gorwing rats. In controls fed ad lib, weight and length gain were better with high protein diets, whereas they were inversely related to the diet protein content in uremic rats. The higher the protein intake, the higher the progressive elevation of BUN and serum creatinine and the mortality rate. Because proteins were supplied by fish flour, their increase was associated with increased mineral content, and the conclusions are restricted to the use of natural proteins: a moderately restricted protein diet securing only the minimal requirements had a beneficial effect on growth and survival of rats with reduced kidney mass. Avoiding any excess in proteins from the early stage of renal disease is suggested.

Animals↗
PubMed1979

Membranous glomerulonephritis with extra-renal disorders in children.

Thirty of 85 children with membranous glomerulonephritis (MGN) had associated extraglomerular disorders. The relation of these associations to membranous glomerulonephritis (MGN) is discussed. The causal relationship of acute hepatitis (5 cases), persistent hepatitis B antigenemia (6 cases), systemic lupus erythematosus (2 cases) and syphilis (1 case) may be ascertained; in similar conditions a definite antigen (Ag) has been found in MGN deposits. The association with SS or SA hemoglobinopathy (3 cases) ans with a preceding streptococcal infection (4 cases) raises the possible responsibility of renal tubular epithelium (RTE) Ag and of a streptococcal Ag. D-penicillamine therapy (1 case) is a well-known cause of MGN although the acting Ag remains unknown. Four children had serum sickness-like symptoms, two had hematologic disorders and two had proximal tubular dysfunction, one of them with proven anti-tubular and anti-alveolar basement membrane antibodies. A decrease in plasma C4, Clq, and factor B with normal C3 was frequently observed. The multiple Ag previously described as causative of MGN are recalled. The prevalent incidence of HBsAg is stressed, and the necessity for further investigations in patients with MGN in order to find an underlying disease is emphasized.

Adolescent↗