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E Günther

Publications and source records attributed to E Günther.

At least 73 records · Page 4Linked to original sources
PubMed1994

The distribution of Tap2 alleles among laboratory rat RT1 haplotypes.

We are reporting the cDNA sequences of Tap2 from two cima and two cimb rat strains. Comparison of the cDNA sequences shows that these alleles fall into two groups, which we refer to as Tap2-A and Tap2-B. We found that alleles from the Tap2-B group are more closely related to the mouse homologue than are Tap2-A alleles, and among the 48 nucleotides which differ between the Tap2-A and Tap2-B cDNAs, three affect restriction sites. We defined pairs of oligonucleotides which allow amplification of the regions bearing these restriction sites from genomic DNA or cDNA, and this technique has been successful for the genotyping of all of the 56 laboratory strains of Rattus norvegicus tested and for five cell lines tested so far. All 14 known RT1 standard haplotypes were tested, and 7 found to belong to the Tap2-B group, and 7 to Tap2-A. We also found that intron sizes among the alleles of the Tap2-B group fall into two subgroups, providing further insight into the phylogeny of these various haplotypes.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1994

A novel, conserved gene of the rat that is developmentally regulated in the testis.

From a rat testis library three overlapping cDNA clones were isolated that represent a novel single-copy gene, designated Tegt. Two transcripts of 2.8 and 1.0 kb were found in each organ tested. The shorter transcript was highly abundant in adult testis. A similar expression pattern was found in the mouse. Analysis of rat RNA from different stages of spermatogenesis indicated that accumulation of the short transcript occurred mainly postmeiotically. The rat Tegt gene maps to Chromosome (Chr) 7, and its mouse homolog to Chr 15.

Aging↗
PubMed1994

Comparative analysis of the three major histocompatibility complex-linked heat shock protein 70 (Hsp70) genes of the rat.

The organization of the three major histocompatibility complex (Mhc)-linked heat shock protein 70 (Hsp70) genes Hsp70-1, Hsp70-2, and Hsp70-3, and the nucleotide sequences of these genes, are presented for the rat. Hsp70-1 and Hsp70-2 gene products are identical at the amino acid level. From the pattern of sequence similarity of the orthologous Mhc-linked Hsp70 genes of rat, human, and mouse, it is concluded that the gene duplications leading to the three-gene cluster occurred before the separation of the primate and rodent lines and that the Hsp70-1 and Hsp70-2 genes of rat and human might have undergone homogenization of their sequences.

Amino Acid Sequence↗
PubMed1994

JM9 strains, a new type of group B streptococci from Japan.

JM9 strains isolated from human carriers and patients in several districts of Japan, represent a new serotype of group B streptococci (GBS, Streptococcus agalactiae). They were first detected in 1983 but are meanwhile prevailing among all other GBS serotypes in Japan. Outside of Japan, strains of this type have not been reported until now. In the present work, N-acetylneuraminic acid was detected in all strains investigated, by chemical analysis as well as by interaction with a sialic acid-binding lectin. This component is characteristic of all analyzed GBS type polysaccharides. In a chicken embryo model, all strains exhibited a very strong virulence. Examination of the antibiotic sensitivity revealed that all strains were susceptible to penicillin, cephalothin, clindamycin, mezlocillin, azlocillin, erythromycin, methicillin, chloramphenicol, tetracyclin, oxacillin and sulfamethoxazole/trimethoprim, whereas all strains were resistant against gentamicin, kanamycin and neomycin. Electron microscopic studies revealed for these strains relatively small capsules but unusually thick cell walls. By immunogold labelling, the type polysaccharide, the group polysaccharide, the lipoteichoic acid and in some strains, the protein R were localized.

Animals↗
PubMed1994

Purification and characterization of hyaluronidase from Streptococcus agalactiae.

Hyaluronidase from two different strains of Streptococcus agalactiae was purified and characterized. The purification was performed successively by chromatography and rechromatography on phenylsepharose, gel filtration with FPLC on Superdex G 200 and isoelectric focusing. The purified hyaluronidase had an isoelectric point of 8.75 and a molecular weight of approximately 116,000 D. It showed maximal enzyme activity at pH 6.30 and 40 degrees C. The Michaelis constant was estimated to be 8.17 x 10(-2) mg/ml. Hyaluronidase was stimulated only by Mg++ and inhibited by Zn++, Al , Cu++ and Fe++ at a final concentration of 10 mmol/l, respectively. The enzyme splitted hyaluronic acid and in low amounts dermatan sulphate and chondroitin sulphate A. Additionally, synthetic polyanions (like polymers of gentisic acid with formaldehyde and hydroxy sulphonic acid with formaldehyde) turned out to be also potent inhibitors of the enzyme.

Hyaluronoglucosaminidase↗
PubMed1994

Restriction fragment length polymorphism of the major histocompatibility complex-linked heat shock protein 70 (Hsp70) genes of the rat.

DNAs from inbred rat strains representing eighteen major histocompatibility complex (RT1) haplotypes have been tested for restriction fragment length polymorphisms of the three heat shock protein 70 (Hsp70) genes mapping into this complex. The DNAs were digested with restriction enzymes BamHI, EcoRI, PstI or PvuII and assayed by probes hybridizing to all three genes or selectively to Hsp70-1, Hsp70-2 and Hsp70-3, respectively. Three to four alleles were detected with each enzyme and in total five different strain distribution patterns could be found. Neither deletions nor amplifications of genes were detected in the three-gene Hsp70 cluster.

Animals↗
PubMed1993

Sequence, expression, and chromosomal assignment of a human sperm outer dense fiber gene.

Outer dense fibers (ODFs) are located on the outside of the axoneme in the midpiece and principal piece of the mammalian sperm tail and may help to maintain the passive elastic structures and elastic recoil of the sperm tail. We have identified and describe here a human gene that is homologous to the Mst(3)CGP gene family of Drosophila melanogaster and encodes an ODF protein of 241 amino acids. The transcribed region has a size of approximately 1 kb and contains two exons of 416 bp and 406 bp, respectively, not including the 3' untranslated region. The gene is expressed in testis but not in human spleen, kidney, or brain and resembles in this respect the expression of the Drosophila Mst(3)CGP gene family in the male germline. An antiserum raised against a synthetic peptide derived from the N-terminus of the encoded sequence identified a protein of approximately 32 kDa in an extract of human sperm flagella. By Southern-blot analyses and in situ hybridization, the ODF gene was localized to band q22 of chromosome 8. The isolation of a human gene encoding a sperm tail protein may provide the ability to identify and investigate, on the molecular level, possible reasons for human male infertility that are dependent on flagellar disturbances.

Amino Acid Sequence↗
PubMed1993

Characterization of a class Ib gene of the rat major histocompatibility complex.

The cDNA and a partial genomic sequence of a rat class I major histocompatibility (RT1) gene, 11/3R, is reported here. The sequence contains several unique amino acid residues at certain positions, mutations in exon 7 (which is not expressed), a mutation of the canonical exon 8 stop codon to a sense codon, and includes a long 3' untranslated region (utr). The structure of exon 7 differs from that found in most rat class I genes and resembles exon 7 of most H-2K,D,L,Q genes. Parts of the 3' noncoding region are homologous to the RT1.A-4 and certain H-2 genes. Expression is detectable by northern blot analysis in mitogen-stimulated lymphocytes only, by polymerase chain reaction (PCR) in each tissue tested. After transfection into L cells 11/3R can be shown to be expressible at the cell surface. Probes derived from the 3' noncoding part crosshybridize with a number of restriction fragments which map to the RT1.C region, thus defining a subfamily of RT1.C region genes. Several members of this subfamily are deleted in the lm1 RT1 mutant. The 11/3R gene presents typical features of a class Ib gene. Aspects of evolution and the potential function of the gene are discussed.

Amino Acid Sequence↗
PubMed1993

Ultrastructural localization of laminin subunits during the onset of mesoderm formation in the mouse embryo.

Using ultrastructural immunogold histochemistry on LR-Gold-embedded 6- and 7-day-old mouse embryos we investigated the appearance of the A- and B1-chains of the laminin molecule during mesoderm formation. With the help of antibodies against the A-chain and the E4 fragment of the B1-chain of the laminin molecule we were able to detect the subunits in vivo. Staining for the E4 fragment of the short arm of the laminin molecule from day 6 was negative. In contrast, strong staining for the A-chain of laminin was observed. Our results show, that the A-chain of laminin appears before the B1-chain in the 6-day-old mouse embryo before a basement membrane is seen between the ectodermal and entodermal cell layers. Furthermore, the staining pattern indicates, that the laminin molecule changes its orientation in the basement membrane of the ectoderm during mesoderm formation. On day 7 staining for the A-chain of laminin and for the E4 fragment was seen in a random distribution throughout the entire basement membrane, whereas in areas were the onset of mesoderm formation was taking place, the E4 fragment was restricted to the edge of the disintegrating basement membrane.

Animals↗
PubMed1993

Factor XII (Hageman) deficiency in women with habitual abortion: new subpopulation of recurrent aborters?

OBJECTIVE: To examine the possible association between factor XII (FXII) deficiency and an elevated number of abortions. DESIGN: Factor XII activity, FXII antigen concentration, other blood clotting parameters, and phospholipid antibodies were examined in venous blood from 43 women with repeated (3 to 7) abortions before the 28th week of gestation but without gynecological and chromosomal abnormalities. The data were compared with those obtained from 49 age-matched women without fetal loss. RESULTS: Eight cases with moderately reduced FXII activity (35% to 68% of normal) could be identified in the abortion group, whereas among controls no abnormalities in FXII activity and antigen concentration were found. The relative occurrence of reduced FXII level was higher among patients with more than three abortions as compared with those with three abortions. CONCLUSION: Repeated abortions may be associated with reduced level of FXII activity of unknown origin.

Abortion, Habitual↗
PubMed1993

Genetic control of the cellular in vitro response to the H-Y antigen in the rat.

The immune response against the male-specific H-Y antigen has been studied in RT1 congenic rat strains by assaying the cytotoxic and proliferative response in vitro after in vivo priming. The capacity to respond is associated with the RT1a and RT1n major histocompatibility haplotypes, and nonresponsiveness with the RT1u haplotype. Both, genes of the RT1.A region, which encodes class I antigens, and of the RT1.B/D region, which includes class II and transporter genes, are involved in the genetic control. In F1 hybrids haplotype preference of H-Y restriction occurs in favor of RT1a. Cross-priming can be induced in F1 hybrids by parental cells for RT1a-restricted cytotoxic and proliferative T cells. Allopriming is successful only in the RT1a-carrying strain, whereas xenopriming with mouse cells could not be elicited. The results are discussed in the context of current views on processing and presentation of antigens, and their relevance for transplantation is pointed out.

Animals↗
PubMed1993

Effect of heat shock on susceptibility of normal lymphoblasts and of a heat shock protein 70-defective tumour cell line to cytotoxic T lymphocytes in vitro.

The effect of heat shock pretreatment of target cells on their lysability by cytotoxic T lymphocytes was analysed. Killing of Concanavalin A-stimulated normal lymphocytes by minor or major histocompatibility antigen-specific cytotoxic T lymphocytes is unchanged or even slightly enhanced after heat shock, whereas cells of the myeloma line Y3, which is derived from one of the lymphocyte donor strains, become nearly resistant to killing after the same pretreatment. Cold target inhibition experiments show that heat-shocked cells are recognized specifically and that untreated and heat-shocked target cells possess similar inhibitory potential. Y3 cells are unable to express the strongly heat-inducible heat shock protein of 70 kDa (hsp70) after heat shock; the acquired resistance is thus independent of hsp70 induction. Possible mechanisms of the different lysability seen in lymphoblasts and tumour cells after heat shock are discussed.

Animals↗
PubMed1993

[Sex education and AIDS prevention].

The well-known deficiencies in sexual education prompt the author to present commendable education programmes by experienced sexual paedagogues. Emancipatory sexual education aims at preparing adolescents for adulthood. Most of the teenagers have other sexual anxieties than an HIV infection. These facts should be utilised for other methods of sexual education.

Acquired Immunodeficiency Syndrome↗