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Biomedical subjects

G Jung

Publications and source records attributed to G Jung.

At least 505 records · Page 28Linked to original sources
PubMed1983

[Representative studies of the vitamin D status of 2-year-old children in Frankfurt am Main].

In a representative sample population of 421 two-year-old Frankfurt children studied for vitamin-D nutritional status, only one case of subclinical rickets was discovered. 93.3% of the children have been a regular vitamin-D supplements during the first 12 month of life, but only 32.7% of them continued to receive the supplement beyond the age of one year. Risk groups were not identified, neither with regard to ethnic groups, nor smaller vitamin-D doses, or any other aspect.

Child, Preschool↗
PubMed1983

Multivariate analysis of plasma enzyme profiles in severe head injury.

We followed the changes in the activities of four enzymes (aldolase, aspartate aminotransferase, creatine kinase, and lactate dehydrogenase) in plasma for four days after head injury. The progression of the changes differs significantly between survivors and nonsurvivors. Stepwise discriminant analysis, involving the four enzymes, allowed us to divide 81 to 92% of head-injured patients (n = 280 selected without conscious bias) correctly into the two groups as early as 72 h after trauma. Most of the patients who were misclassified according to our biochemical criteria had received phenobarbital for sedation. Valuable prognostic information in head injury evaluation may thus be obtained by daily determination of enzymatic activities of these four enzymes.

Aspartate Aminotransferases↗
PubMed1983

Interaction of metal-complexing compounds with lymphocytes and lymphoid cell lines.

A variety of metal-complexing flavonoids (beta-hydroxyethyl rutoside, catechin, naringin, taxifolin, and quercetin) as well as several compounds which form mainly iron complexes (bathophenathroline, bathophenanthrolinebisulfonic acid, desferri-ferrioxamine B, ethylenediamine-di-o-hydroxyphenylacetic acid) were tested for their effects on mitogen-free and mitogen-activated mouse splenocyte cell cultures and on two human cell lines (Daudi, Bristol-8). The compounds strongly inhibited the incorporation of [3H]thymidine into DNA at agent concentrations ranging from 10 to 500 microM. On the other hand, at subinhibitory concentrations, slightly enhancing or synergistic effects were observed. We conclude that immune cell behavior can be bidirectionally influenced by the presence of metal-complexing agents, depending on their concentration in the medium.

Animals↗
PubMed1982

Membrane-associated actin from the microvillar membranes of ascites tumor cells.

A membrane fraction (MF2) has been purified from isolated microvilli of the MAT-C1 subline of the 13762 rat mammary ascites adenocarcinoma under conditions which cause F-actin depolymerization. This membrane preparation contains actin as a major component, although no filamentous structures are observed by transmission electron microscopy. Membranes were extracted with a Triton X-100-containing actin-stabilizing buffer (S buffer) or actin-destabilizing buffer (D buffer). In D buffer greater than 90% of metabolically labeled protein and glycoprotein was extracted, and 80-90% of these labeled species was extracted in S buffer. When S buffer extracts of MF2 were fractionated by either gel filtration on Sepharose 6 B or rate-zonal sucrose density gradient centrifugation, most of the actin was found to be intermediate in size between G- and F-actin. In D buffer most of the MF2 actin behaved as G-actin. Extraction and gel filtration of intact microvilli in S buffer also showed the presence of the intermediate form of actin, indicating that it did not arise during membrane preparation. When [35S]methionine-labeled G-actin from ascites cells was added to S buffer extracts of MF2 and chromatographed, all of the radioactivity chromatographed as G-actin, indicating that the intermediate form of actin did not result from an association of G-actin molecules during extraction or chromatography. The results of this study suggest that the microvillar membrane fraction is enriched in an intermediate form of actin smaller than F-actin and larger than G-actin.

Actins↗
PubMed1982

[Neocarzinostatin: molecular mechanism of action and prospects for clinical use].

This article describes the properties and biological actions of the antitumor protein neocarzinostatin which stands for a whole group of high molecular weight antitumor antibiotics. Special emphasis is given to the development of our understanding of the molecular mechanism of neocarzinostatin action. From this mechanism of action far-reaching perspectives concerning the clinical application of neocarzinostatin are discussed.

Amino Acid Sequence↗
PubMed1982

B-lymphocyte mitogenicity in vitro of a synthetic lipopeptide fragment derived from bacterial lipoprotein.

Lipoprotein from the outer membrane of Escherichia coli is a potent mitogen towards lymphocytes of different species. A lipopeptide fragment corresponding to the N-terminal part of the lipoprotein was prepared by chemical synthesis. The mitogenicity of the compound was demonstrated by measuring the incorporation of both [3H]thymidine into DNA and [3H]uridine into RNA at various times after the addition of lipopeptide to mouse spleen cell cultures. The lipopeptide also activated B-lymphocyte development into immunoglobulin secreting cells, as shown by a hemolytic plaque assay. The mitogenicity of the synthetic compound was comparable to the activity of the B-lymphocyte mitogens lipoprotein and lipopolysaccharide. Thus, it was shown that a fragment of a bacterial surface component prepared by chemical synthesis, exhibits a marked biological activity.

Animals↗
PubMed1982

[Isolation, structure elucidation and synthesis of a hexapeptide from the hemodialysate of uremic patients].

Lyophilised hemodialysates of uremic patients were fractionated on Sephadex G-15 for investigation of potential uremic toxins. One of the oligopeptides found in the fraction of postulated toxins was purified to homogeneity by gel, reversed-phase and adsorption chromatography and by high-performance liquid chromatography. Dansyl Edman degradation revealed the sequence Ala-Phe-Phe-Gly-Glu, which was synthesized by the solid-phase method. The comparison of synthetic and natural hexapeptide by chromatographic methods, mass spectrometry, 1H- and 13C-nuclear magnetic resonance proved the correct sequence. The peptide showed only weak activity in immunological test systems and in the lymphocyte proliferation test.

Amino Acid Sequence↗
PubMed1981

Isolation of alpha-actinin from sarcoma 180 ascites cells plasma membranes and comparison with smooth muscle alpha-actinin.

alpha-Actinin from Sarcoma 180 ascites cell plasma membranes was purified after extraction in 10 mM Tris, 1 mM EDTA, 1 mM mercaptoethanol, pH 8.5, by chromatography on DEAE and hydroxyapatite for comparisons with smooth muscles alpha-actinin purified from turkey gizzard by the same procedure. The two proteins were found to be very similar by sedimentation analysis, gel filtration and dodecyl sulfate gel electrophoresis. Direct comparisons of smooth muscle, skeletal muscle and ascites alpha-actinin by amino acid analysis indicated a closer relationship between the smooth muscle and ascites proteins than between the smooth and skeletal muscle proteins. Both smooth muscle and ascites alpha-actinins cross-link F-actin filaments. The results suggest that the smooth muscle protein is a better system for understanding properties of non-muscle alpha-actinins than is the skeletal muscle protein.

Actinin↗
PubMed1981

[Synthesis, 13C-NMR and CD study of the N-terminal tridecapeptide sequence of human fibroblast interferon].

The N-terminal sequence H-Met-Ser-Tyr-Asn-Leu-Leu-Gly-Phe-Leu-Gln-Arg-Ser-Ser-OH (FIF[1-13]) of human fibroblast interferon HuIFN-beta(Fi) has been synthesized using the solid-phase method. After esterification of N-tert-butyloxycarbonyl-O-benzyl-L-serine cesium salt with chloromethylated polystyrene-1% divinylbenzene (loading 0.25 mmol/g) the tridecapeptide was built up stepwise. Coupling reagents and N-tert-butyloxycarbonylamino acids were used in a six-fold excess. For the second coupling 1-hydroxybenzotriazole was added during carbodiimide and 4-nitrophenyl glutaminate or asparaginate couplings. Side chain functions were masked: O-benzylserine, O-(2,6-dichlorobenzyl)tyrosine and Ng-tosylarginine. After an acetylation step the N-protection was removed by trifluoroacetic acid/dichloromethane 1:1, and for neutralisation triethylamine/-chloroform 1:9 were used, both steps with a prewash. The Ng-tosyltridecapeptide was split-off from the resin by HBr in trifluoroacetic acid and purified by repetitive precipitations. After deprotection of the guanidino group of arginine with sodium in liquid ammonia, the peptide was precipitated from acetic acid/water, chromatographed on Sephadex G-25 coarse in acetic acid/water 1:1 and precipitated from acetic acid/ether and dimethylformamide/acetone. After purification by multiplicative counter-current distribution in butanol/-5% acetic acid/propanol 5:5:1 the tridecapeptide was pure according to chromatographic, electrophoretic, enzymatic and instrumental analyses. The peptide was investigated by circular dichroism in trifluoroethanol and hexafluoroacetonesesquihydrate and 13C-nuclear magnetic resonance, which revealed an alpha-helical conformation. In order to obtain a suitable antigen the tridecapeptide was coupled to poly(L-lysine) (molecular mass 37300) via N,N'-dicyclohexylcarbodiimide followed by dialysis. The resulting poly(L-lysine)-FIF[1-13] conjugate showed a loading of 17.8 mol FIF[1-13] per mol poly(L-lysine).

Amino Acid Sequence↗
PubMed1981

[Synthesis and 13C-NMR spectra of the N-terminal decapeptide sequence of human lymphoblast interferon].

The N-terminal sequence 1-10 of interferon HuIFN-alpha(Ly) from human lymphoblasts Ser-Asp-Leu-Pro-Gln-Thr-His-Ser-Leu-Gly (LIF[1-10]) was synthesized by the Merrifield method. N-tert-Butyloxycarbonylglycin was esterified via its cesium salt with a chloro-methylated polystyrene-1% divinylbenzene support yielding a loading of 0.3 mmol/g. Double couplings, each with a five-fold excess of N-protected amino acid, were performed with N,N'-dicyclohexylcarbodiimide and 1-hydroxybenzotriazole, followed by an acetylation step. N-tert-Butyloxycarbonyl-L-amino acids with O-benzyl protection for serine, threonine, and Nim-2,4-dinitrophenyl protection for histidine, and N-fluorenylmethyloxycarbonylaspartic acid beta-tert-butyl ester were used. N-tert-Butyloxycarbonyl-glutamine was coupled as 4-nitrophenyl ester in the presence of 1-hydroxybenzotriazole. The butyloxycarbonyl groups of the residues 3 to 10 were removed with trifluoroacetic acid in dichloromethane; the 9-fluorenylmethyloxycarbonyl group was split off with diethylamine. After quantitative hydrazinolysis in dimethylformamide, chromatography on Sephadex LH-20 with methanol and reversed-phase chromatography on silica gel RP-8 with methanol/water 9:1, the decapeptide hydrazide Boc-Ser(Bzl)-Asp(But)-Leu-Pro-Gln-Thr(Bzl)-His-Ser(Bzl)-Leu-Gly-NH-HN2 was isolated in pure state. The partially protected decapeptide was characterized by 13C-NMR spectroscopy, analysed, and linked with poly(L-lysine) (molecular mass 37 300) via its azide and also using m-xylylene diisocyanate. After a deprotection step the polylysine-LIF[1-10] antigens were dialyzed and lyophilized. Furthermore the free decapeptide LIF[1-10] was split-off from the resin using HBr/CF3CO2H, followed by mercaptoethanol treatment. After purification on Sephadex G-15 with 0.1 M acetic acid and on the reversed-phase silicagel RP-8 with methanol/water 9:1 water soluble LIF-[1-10] was obtained in pure state as shown by thin-layer-chromatography, electrophoreses amino acid analysis and 13C-NMR spectroscopy.

Amino Acid Sequence↗
PubMed1981

[Colonoscopy in children].

Until now colonoscopies have rarely been carried out in children on contrary to adults. Within two years we have submitted to this method, more than 80 patients between the first and 19th year of their lives, previously those ones who were in preschool- and school-age. The main indication for the endoscopy were bloody stools and mild inconstant abdominal pain. In most of the children we found different degrees and extents of an inflammatory process of the colon. The histological diagnosis was in 38 patients an unspecific chronic colitis, in 2 cases a solitary polyp, and only once a hemangioma. Despite of the colitis, nearly all children were in a relatively good physical condition. We think that the unknown and untreated colitis in children is very dangerous for them with regard to the develop of colon-carcinoma in their later lives.

Adolescent↗
PubMed1980

A model for the activation and inactivation of neocarzinostatin, an antitumor protein.

Sulfhydryl compounds specifically activate and inactive neocarzinostatin as measured by the in vitro strand scission of T2 DNA. This effect, and evidence for strained disulfides in the molecule, leads us to propose a model of activation and inactivation. We suggest that neocarzinostatin reacts with sulfhydryl reagents to produce a short-lived active form which may react with DNA or proceed irreversibly via a conformational change to an inactive form (preneocarzinostatin). Three parameters of neocarzinostatin activity (inactivation rate, single strand break plateau position, and initial single strand break rate), have been measured for various sulfhydryl concentrations, and the observed results agree well with values expected from a simplified mathematical treatment of the model, thus supporting the assumptions made.

Antibiotics, Antineoplastic↗
PubMed1980

The generalization of pre-neocarzinostatin and antagonism of neocarzinostatin-induced DNA scission in vitro.

Pretreatment of the antitumor protein neocarzinostatin with heat, ultraviolet or white light, and thiols inactivates the drug, as measured by the cessation of phage T2 DNA strand scission in vitro. The inactive forms obtained are identical with pre-neocarzinostatin on the basis of isoelectric focusing, molecular weight determination, and changes in circular dichroism spectra. In incubations together with neocarzinostatin and T2 DNA, the inactive form inhibits strand scission to a considerable degree. This result suggests that both forms compete for a limited number of available DNA binding sites.

Antibiotics, Antineoplastic↗
PubMed1980

Nosiheptide, a sulfur-containing peptide antibiotic isolated from Streptomyces actuosus 40037.

Nosiheptide (9671 R.P.) isolated from Streptomyces actuosus 40037 (NRRL 2954) is a sulfur-containing polypeptidic antibiotic, quite different from all the other members of this family. Very active in vitro against gram-positive bacteria, it is inactive in vivo in experimentally infected mice. Not toxic, even at high dose, it may be used as a feed additive for chickens and pigs and it shows a favourable effect on the growth and conversion index.

Animal Feed↗