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Biomedical subjects

H Kresse

Publications and source records attributed to H Kresse.

At least 145 records · Page 8Linked to original sources
PubMed1979

N-Acetylglucosamine-6-sulfate sulfatase from human urine.

N-Acetylglucosamine-6-sulfate sulfatase, which liberates sulfate from the N-acetylglucosamine 6-sulfate residue at the nonreducing terminus of a 3H-labeled trisaccharide prepared from heparan sulfate, was purified 136-fold from human urine. The final N-acetylglucosamine-6-sulfate sulfatase preparation was free of all lysosomal sulfatases known to act on sulfated polysaccharides and gave a single band in polyacrylamide gel electrophoresis. The enzyme appears to be a glycoprotein with a molecular weight of around 97,000 and displays considerable charge heterogeneity. Multiple forms with pI values between 5.4 and 8.3 with a maximum at pH 7.7 were detected. The enzyme acts on the 3H-trisaccharide with a pH optimum at 5.5 and is active towards the sulfated monosaccharides N-acetylglucosamine 6-sulfate and glucose 6-sulfate. Although predominantly in exosulfatase, the enzyme catalyzes hydrolysis of sulfate from internal N-acetylglucosamine 6-sulfate moieties at a low rate. The Km for the 3H-trisaccharide, N-acetylglucosamine 6-sulfate, and glucose 6-sulfate were 0.15, 1.5, and 7.7 mM, respectively. The enzyme is inhibited by albumin, Hg2+, PO43-, SO42-, and CN-. Enzyme activity was highest in kidney and cultured fibroblasts but could be demonstrated in all human tissues tested.

Acetylglucosamine↗
PubMed1979

Multiple deficiency of mucopolysaccharide sulfatases in mucosulfatidosis.

Fibroblasts of four patients affected with mucosulfatidosis (multiple sulfatase deficiency, Austin variant of metachromatic leukodystrophy) were assayed for activities of the five sulfatases known to degrade mucopolysaccharides. These were iduronide 2-sulfate sulfatase, sulfamidase, N-acetyl-galactosamine 6-sulfate sulfatase, arylsulfatase B (N-acetylgalactosamine 4-sulfate sulfatase), and N-acetylglucosamine 6-sulfate sulfatase. The activities of these five sulfatases were severely depressed, thus confirming the known deficiency of arylsulfatase B and the absence of the Hunter and Sanfilippo III A corrective factors that have iduronide 2-sulfate sulfatase and sulfamidase activity, respectively. Together with earlier reports of the deficiencies of arylsulfatases A and C, cholesteryl sulfatase, and dehydroepiandrosterone sulfatae, mucosulfatidosis is now characterized by the deficiency of nine different sulfatases.

Acetylglucosamine↗
PubMed1979

Technological problems of miniaturized insulin dosing devices and some approaches to clinical trials.

With the long-term goal of developing implantable insulin dosing devices, we have since 1971 developed various types of programme-controlled units for clinical research. In the initial stage, a 24-hour, fixed-programme bed-side device has been in clinical use since 1973. The good results with even labile diabetics has supplied the basis for the further development of sensorless units. Via intermediate stages, two types of miniaturized portable devices were constructed: fixed-programme and demand-programme devices. The essential equipment components have been optimized with a view to later implantability: hermetically sealed capsule for the dosing device, refilling membrane for the insulin reservoir, bubble-free drawing off of the insulin via a wick from a collapsible silicone reservoir, the stepping motor-driven roller pump of approx. 9 cm3 volume, an energy consumption of about 50 mu W, and electronic safety and alarm circuits. Because of stability problems of the insulin, the neutral insulin U-1000 used initially was changed to acid insulin U-100 (both from Hoechst).

Animals↗
PubMed1978

Metabolism of sulfated glycosaminoglycans in cultured endothelial cells and smooth muscle cells from bovine aorta.

The glycosaminoglycan metabolism of cultured endothelial cells and of cells grown from the intima and from the media layer of bovine aorta thoracia was investigated in a comparative study. The following results were obtained: 1. Endothelial cells have in common with intima and media cells the distribution of newly formed sulfated glycosaminoglycans into extracellular, pericellular and intracellular compartments. Endothelial cells, however, synthesize lower amounts of glycosaminoglycans and distribute them in a different ratio into the three pools. 2. Though all the various cell lines synthesize chondroitin 4-sulfate, chondroitin 6-sulfate, dermatan sulfate, heparan sulfate and small amounts of keratan sulfate, endothelial cells exhibit a unique distribution pattern of sulfated glycosaminoglycans in each of the three compartments. Generally, a high proportion of heparan sulfate and chondroitin 6-sulfate and a very low dermatan sulfate content was detected. 3. Heparan sulfate produced by endothelial cells has a higher N-sulfonate content when compared with that from other sources. The cell membrane-associated heparan sulfate, especially, exhibits some heparin-like features as judged by nitrous acid degradation and susceptibility towards heparitinase.

Animals↗
PubMed1978

A sensitive procedure for the diagnosis of N-acetyl-galactosamine-6-sulfate sulfatase deficiency in classical Morquio's disease.

The trisaccharide 6-sulfo-N-acetylgalactosamine-glucuronic acid-6-sulfo-N-acetyl-[1-3H]galactosaminitol was used as a substrate for the determination of N-acetylgalactosamine-6-sulfate sulfatase activity. The amount of liberated sulfate was measured indirectly by separating monosulfated reaction products from the substrate on Dowex 1 X 2 microcolumns in a simple two step procedure. Fibroblast homogenates from patients with various genotypes, except classical Morquio's disease, released 410 +/- 90 pmol sulfate/h/mg cell protein. The enzyme exhibited a pH optimum of pH 4.8 and a KM of about 1 X 10(-4) mol/1. It was strongly inhibited by phosphate, sulfate and chloride ions. In three cell lines from patients with classical Morquio's disease a residual activity between 1 and 2% of the mean normal activity was found. All cell lines tested released sulfate from 6-sulfo-N-acetylglucosamine-glucuronic acid-[1-3H]-anhydromannitol. Cell extracts from cultured amniotic fluid cells exhibited a N-acetylgalactosamine-6-sulfate sulfatase activity between 120 and 320 pmol/h/mg protein. An enzyme activity of 370 +/- 100 pmol sulfate/h/mg protein was found in peripheral leucocytes from healthy donors. The determination of N-acetyl-galactosamine-6-sulfate sulfatase activity in one family with an affected patient indicated that the enzyme deficiency is also expressed in leucocytes.

Amniotic Fluid↗
PubMed1978

[Pathobiochemical aspects of lysosomal enzymes with special reference to lysosomal storage diseases (author's transl)].

Lysosomal hydrolases participate substantially in the degradation of all classes of biological macromolecules. They act physiologically within the lysosome. The enzymes are either primarily included within primary lysosomes or are transported to these cell organelles after secretion and subsequent adsorptive pinocytosis. The involvement of these enzymes in a variety of pathological conditions can be understood on the basis of the known functions of lysosomal hydrolases. Inactivity of one or several of the enzymes causes lysosomal storage disorders. Similar metabolic consequences are found when the enzymes are unable to be concentrated within the lysosome. Lysosomal hydrolases participate, furthermore, in the pathogenesis of numerous diseases. A distinction can be made between lysosomal overload, pathologically-increased enzyme secretion into the extracellular space, and a release of lysosomal enzymes into the cytosol.

Acid Phosphatase↗
PubMed1978

[Studies on pinocytosis of proteoglycans and glycosaminoglycans (author's transl)].

Comparative studies were performed on the uptake of 35SO4-labelled proteoglycans and of free 35SO4-glycosaminoglycan chains by cultured skin fibroblasts. Proteoglycans as well as protein-free polysaccharide chains are internalized by adsorptive pinocytosis. The maximum capacity for endocytosis of proteoglycans is about four times higher than for glycosaminoglycan chains when referred to disaccharide units. On a molar basis about 10 times more glycosaminoglycan chains than proteoglycans can be internalized within a given time. Since unlabelled carbohydrate chains do not compete for the uptake of labelled proteoglycans it seems likely that different receptors exist on the cell surface for endocytosis of both types of macromolecules. 14C-labelled hyaluronate was neither pinocytosed to a measurable extent by skin fibroblasts nor by intima cells cultured from the thoracic aorta. Rat liver hepatocytes efficiently internalized hyaluronate by adsorptive pinocytosis. It was concluded from competitive experiments with hyaluronate oligosaccharides that hyaluronate has to interact with at least two receptor molecules on the cell membrane to achieve endocytosis.

Fibroblasts↗
PubMed1978

Studies on secretion and endocytosis of macromolecules by cultivated skin fibroblasts. Effects of anti-microtubular agents on secretion and endocytosis of lysosomal hydrolases and of sulphated glycosaminoglycans.

Fibroblasts were incubated in the presence of the anti-microtubular drugs colchicine, vinblastine and vincristine. In concentrations between 10nm and 1 mM these drugs stimulated the secretion of beta-N-acetylglucosaminidase, alpha-N-acetylglucosaminidase and beta-glucuronidase, but not of beta-galactosidase. The endocytosis of beta-N-acetylhexosaminidase and alpha-N-acetylglucosaminidase, but not of beta-glucuronidase, was inhibited at drug concentrations higher than 0.1 micrometer. Formation, secretion and association with the cell membrane of sulphated proteoglycans were not affected by anti-microtubular drugs. Endocytosis of sulphated proteoglycans and their subsequent degradation was inhibited by drug concentrations above 0.1 micrometer. The inhibition of intracellular glycosaminoglycan degradation led to a moderate storage of these compounds. These results suggest that microtubules participate in the control of secretion and endocytosis of lysosomal enzymes, and in the endocytosis and degradation of lysosomal substrates such as sulphated proteoglycans.

Acetylglucosaminidase↗
PubMed1978

A circadian susceptibility/resistance rhythm for potassium cyanide in male BALB/cCr mice.

Circadian rhythms in mortality and/or survival time following a single intraperitoneal injection of a LD50 of potassium cyanide were studied. In two investigations, different but comparable subgroups of inbred male BALB/cCr mice were treated at 4-h intervals (under conditions standardized for chronobiologic study) during 24-h spans. Mice were observed for exact time-to-death during the first hour after treatment as well as overall mortality during the entire 24-h post-injection span following each KCN treatment timepoint. In both studies, mortality from KCN exhibited a 24-h rhythm. Highest mortality occurred in mice injected at 1600 (80% mortality) in Experiment 1 and 2000 (100% mortality) in Experiment II. Lowest mortality occurred at 0400 (40% mortality) in Experiment I and 0800 (30% mortality) in Experiment II. The need to consider the circadian organization of physiologic function when bioassaying toxicity is discussed.

Animals↗
PubMed1978

Sanfilippo syndrome type C: deficiency of acetyl-CoA:alpha-glucosaminide N-acetyltransferase in skin fibroblasts.

Removal of N-sulfated glucosamine residues during degradation of heparan sulfate is accomplished by the sequential action of three enzymes. Action of sulfamidase results in the formation of alpha-glucosaminide residues. Removal of these groups requires conversion to alpha-N-acetylglucosaminide by the action of an acetyltransferase in the presence of acetyl-CoA, followed by hydrolysis by alpha-N-acetylglucosaminidase. In fibroblast homogenates from three patients with Sanfilippo syndrome type C (mucopolysaccharidosis III C), a biochemical variant of the Sanfilippo syndrome, complete deficiency of the acetyl-CoA:alpha-glucosaminide N-acetyltransferase activity was detected. Activities of all lysosomal hydrolases known so far to degrade mucopolysaccharides, including those of sulfamidase and alpha-N-acetylglucosaminidase, were in the range of controls. Acetyl-CoA:alpha-glucosaminide N-acetyltransferase activity was normal in fibroblasts of patients with other genetic mucopolysaccharidoses, including Sanfilippo syndrome A and B.

Acetyltransferases↗
PubMed1978

A new biochemical subtype of the Sanfilippo syndrome: characterization of the storage material in cultured fibroblasts of Sanfilippo C patients.

Fibroblasts cultured from the skin of three unrelated patients with the clinical symptoms of the Sanfilippo syndrome (mucopolysaccharidosis III) accumulated intracellularly excessive amounts of heparan sulfate and showed a lengthened turnover time for this mucopolysaccharide. They exhibited, however, neither a deficiency of heparan sulfate sulfamidase or alpha-N-acetylglucosaminidase nor of any other known glycosaminoglycan-degrading hydrolase. This new mucopolysaccharidosis was therefore designated as type C of the Sanfilippo syndrome. The abnormal heparan sulfate metabolism of Sanfilippo C fibroblasts could not be normalized by addition of crude urinary proteins or concentrated secretions from normal fibroblasts to the culture medium or by cocultivation with normal fibroblasts. The accumulated heparan sulfate was characterized by a reduced negative net charge. A small proportion of it could be adsorbed onto a cation exchange resin. It was sensitive to nitrous acid degradation under conditions where glucosamine residues with free amino groups are attacked. It is therefore suggested that the primary defect in this new mucopolysaccharidosis concerns the step which follows the hydrolysis of N-sulfonate groups in heparan sulfate degradation.

Adolescent↗
PubMed1978

Morphological and autoradiographical characterization of membrane-like layers surrounding cultured fibroblasts.

Two membrane-like layers of approximately 7 nM thickness were observed in ultrathin cross-sections of flat-embedded cultured fibroblasts. One "membrane", underlying the cell-monolayer, possibly established contacts between cells and substratum. The other "membrane" covered the whole cell culture. These "membranes" were at least partially synthesized by the cells themselves, as was shown by high resolution autoradiography. With regard to our biochemical findings, the autoradiographical results showed that components of these "membranes" consisted of sulfated proteoglycans and may be the morphological equivalent to the biochemically well-defined cell surface associated material, the so-called pericellular pool of glycosaminoglycans.

Animals↗
PubMed1977

Beta-glucuronidase deficiency in a girl with unusual clinical features.

beta-glucuronidase deficiency in fibroblasts, leucocytes and in serum and increased urinary excretion of mucopolysaccharides were found in a girl, now 13 years old, who exhibits some features of a mucopolysaccharidosis such as moderate mental deficiency, craniofacial dysmorphism, a short neck, protruding sternum, vertebral deformities and corneal clouding. Coarse granulations were found in her leucocytes. The liver and spleen are not enlarged and there is no gingival hyperplasia. Additional features, hitherto undescribed, are hydronephrosis and defective ossification of the medial carpal and tarsal bones. Low enzyme activity in the parents and a normal brother suggests heterozygosity.

Adolescent↗
PubMed1977

Mucopolysaccharidosis III A (Sanfilippo disease type A). Histochemical, electron microscopical and biochemical findings.

This is a report of two brothers iwth mucopolysaccharidosis. The 8- and 10-year-old boys presented the characteristic clinical symptoms of the syndrome in their entirety. Both had a highly increased excretion of heparan sulfate in urine. The elder boy died and was autopsied and diagnosed as having Sanfilippo disease Typ A by a drastic reduction of heparan sulfate sulfamidase activity in organ extracts. Histochemically, highly water-soluble, sulfate acid mucopolysaccharides were demonstrated in liver, spleen, and cerebrum of the deceased child. Chemical analyses revealed a 12-fold increase of sulfated mucopolysaccharide in the patients liver and a 4.5-fold increase in the cerebrum when compared with normal controls. The sulfated polysaccharide consisted mainly of heparan sulfate, which was of low molecular size, heterogeneous in charge, and rich in its sulfamino hexose content. In addition, the gangliocytes of cerebrum and cerebellum had accumulated glycolipids. Electron microscopically the storage cells were overloaded with lysosomal residual bodies. The mitral valve was also involved in the storage process, which is a rare manifestation of the Sanfilippo syndrome. Acid mucopolysaccharides were deposited intracellularly as well as extracellularly in the mitral valve tissue. Polarisation microscopically there was found a change from normally positive to negative birefringence in the connective tissue ground substance of the mitral valve when containing stored mucopolysaccharides.

Autopsy↗