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61.
PCR analysis of the Y chromosome long arm in azoospermic patients: evidence for a second locus required for spermatogenesis 总被引:20,自引:2,他引:20
Kobayashi Kazuhiro; Mlzuno Kunihiko; Hida Akiko; Komakl Rie; Tomita Keiko; Matsushita Ikumi; Namlki Mikio; Iwamoto Teruaki; Tamura Shohzoh; Minowada Shlgeru; Nakahori Yutaka 《Human molecular genetics》1994,3(11):1965-1967
We analyzed DNA from 63 Japanese men with either azoospermiaor severe oligospermia whose Y chromosomes were cytogeneticallynormal. A total of 16 loci were examined: 15 loci on the longarm between DYS7E and DYZ1, and the YRRM1 locus, a candidategene for the azoospermic factor, AZF. One patient with a perlcentricinversion of the Y chromosome was also included. We detectedmicro-deletions in ten individuals. The YRRM1 gene was Involvedin only three of them. The remaining seven patients showed deletionbetween DYS7C and DYS239 in common, indicating the presenceof at least one additional gene, deletion of which causes azoospermia. 相似文献
62.
63.
Gert Baumann Stephan B. Felix Claus D. Heidecke Gotthard Rieß Ursula Loher Liesel Ludwig Prof. Dr Hans Blömer 《Inflammation research》1984,15(3-4):216-228
Left ventricular infarction (AMI) was produced in experimental animals and the contractile response to -adrenergic and H2-histaminergic stimulation by isoproterenol and impromidine tested in the isolated perfused heart preparation. Adenylate cyclase activity as well as binding characteristics of [3H]-dihydroalprenolol ([3H]-DHA), [3H]-methyl-tiotidine ([3H]-TIOT) and [3H]-quinuclidinyl benzilate ([3H]-QNB) to cardiac
1-, H2- and cholinergic muscarinic receptors were determined in sarcolemmal membrane preparations of the right ventricle of the same hearts. In addition, an attempt was made to elucidate the therapeutic value of post-AMI treatment with impromidine in the presence and absence of-sympathomimetic, in contrast to administration of prenalterol and the conventional therapy with -sympathomimetic drugs, e.g. dobutamine. Three days post-AMI the dose-response curve for isoproterenol of right ventriculardP/dt
max was significantly depressed, while the inotropic effect of impromidine was not impaired. Stimulation of adenylate cyclase activity by isoproterenol was reduced by 80% whereas impromidine and NaF stimulation rates were unaltered. Receptor-binding studies indicated a 90% loss and 10-times lowered affinity (K
D) of the remaining -receptors while specific [3H]-TIOT- and [3H]-QNB-binding was unchanged.Administration of dobutamine increased mortality rates and extension of infarct size, led to a further decrease in contractile response to isoproterenol, induced complete insensitivity of adenylate cyclase to isoproterenol stimulation and caused pronounced additional reduction of number and affinity of [3H]-DHA-binding sites. In contrast, all above alterations were prevented by treatment with either prenalterol or combined administration of impromidine plus metoprolol. It is concluded, that these alterations in the non-ischemic, uninvolved myocardium post-AMI are the result of catecholamine-induced specific damage of sarcolemmal -receptors. Furthermore, treatment with H2-agonists in combination with -blocking agents may have beneficial effects, whereas conventional therapy with -sympathomimetic drugs tends to worsen the already depressed function of the -adrenergic stimulation mechanism.Supported by grants Ba 666/1 and Ba 666/2-2 from the Deutsche Forschungsgemeinschaft (DFG).Data presented in this paper are part of a doctoral thesis by Dr S.B. Felix. 相似文献
64.
65.
The 5' and 3' terminal sequences of the replicative form (RF) of RNA of a flavivirus, the Japanese encephalitis (JE) virus, strain Ja0ArS982, have been determined by in vitro labelling and mobility shift analysis. The plus strand sequence was 5'AGAAGUUUAUCUGUGUGAA...UCUOH3', while the minus strand sequence was 5'AGAUCCUGUGUUCUUCCUCA...UCUOH3'. These sequences were similar to those of West Nile (WN) virus being identical in 12 nucleotides at the 5'terminal of the minus strand, and in the 5'terminal dinucleotides, 5'AG3'. Somewhat more internal hexanucleotides 5'CUGUGU3' are conserved among 3 flaviviruses, the JE, WN, and yellow fever viruses. 相似文献
66.
Identification of fibroin-derived peptides enhancing the proliferation of cultured human skin fibroblasts 总被引:6,自引:0,他引:6
We previously reported that the fibroin of the silkworm Bombyx mori enhanced the proliferation of cultured human skin fibroblasts. In this work, the fibroin was digested by chymotrypsin, and the resulting peptide fragments were fractionated and assayed for their biological activity. Two peptides that promoted fibroblast growth were isolated and identified to be VITTDSDGNE and NINDFDED. Both sequences are found in the N-terminal region of the fibroin polypeptide and are thought to be the active principle of fibroblast growth-promoting activity. 相似文献
67.
Improved enzyme-linked immunosorbent assay using C-terminal truncated recombinant antigens of Babesia bovis rhoptry-associated protein-1 for detection of specific antibodies
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Boonchit S Xuan X Yokoyama N Goff WL Waghela SD Wagner G Igarashi I 《Journal of clinical microbiology》2004,42(4):1601-1604
An enzyme-linked immunosorbent assay (ELISA) based on a recombinant rhoptry-associated protein-1 (RAP-1) of Babesia bovis has been previously developed, but it was imperfect because some cross-reactions were still present in Babesia bigemina-infected bovine sera. To improve its accuracy for the specific detection of the antibodies to B. bovis, we constructed three C-terminal truncated recombinant antigens of the RAP-1-rCT1 (amino acids [aa] 301 to 408), rCT2 (aa 388 to 490), and rCT3 (aa 466 to 565)-by using a baculovirus expression system and evaluated their diagnostic potentials using ELISA. rCT1 and rCT2 were better diagnostic antigens in their sensitivities and diagnostic efficiencies than rCT3, although none of the recombinant antigens showed any cross-reactivity to B. bigemina-infected bovine sera. These results confirmed that the N-terminal 300-aa region caused cross-reactivity of the entire RAP-1 antigen, and the C-terminal truncated recombinant antigens were shown to be useful reagents for species-specific serodiagnosis. 相似文献
68.
Dr Takanori Kawaguchi Tomohisa Ono Hironao Wakabayashi Seiji Igarashi 《Clinical & experimental metastasis》1994,12(3):203-212
Rat ascites hepatoma AH7974 cells strongly expressed antilaminin antibody-reactive substances (laminin-like substances) andGriffonia simplicifolia isolectin B4 (GS)-reactive carbohydrate (alpha)-d-galactose; alpha-Gal) on their cell surface. The alpha-Gal expression was not apparently influenced by the pretreatment of cells with methanol. The cell membrane laminin-like substances had approximate molecular weights of 150, 62 and 56 kDa in denaturating reducing conditions, of which the 62 and 56 kDa bands were stained with GS. The cell membrane molecules bearing alpha-Gal were 62 and 56 kDa and were stained with antilaminin antibody. Therefore, the major molecules bearing alpha-Gal residues of AH7974 cell membrane are considered to be laminin-like substances. To determine the role of the substances in metastasis, we selected four cell lines (74AD, 74AD-f, 74FL, 74FL-a) from AH7974 in culture. 74AD and 74FL-a are adherent lines and 74AD-f and 74FL are floating lines. All of these cell lines strongly expressed laminin-like substances, but a marked difference was found in expression of alpha-Gal, which was most strongly expressed by 74FL, followed by 74AD, and rarely by 74AD-f and 74FL-a; the staining intensity was positively correlated with their experimental lung-colonizing potential. Cell membrane laminin-like substances were 200, 97, 62, 56 and 46 kDa and among them 62 and 56 kDa molecules were glycosylated with alpha-Gal. The pretreatment of 74FL cells with antilaminin antibody or with human type A serum (containing natural antibody to alpha-Gal epitope) depressed remarkably the lung-colonizing potential of the cells. These results suggest that the expression of 62 and 56 kDa laminin-like substances with alpha-Gal residues on tumor cell surfaces is one of the determinants associated with lung-colonizing potential of these cells. 相似文献
69.
Takiyama Y; Sakoe K; Soutome M; Namekawa M; Ogawa T; Nakano I; Igarashi S; Oyake M; Tanaka H; Tsuji S; Nishizawa M 《Human molecular genetics》1997,6(7):1063-1068
To investigate the mechanism of the meiotic instability of expanded CAG
repeats in the gene for Machado-Joseph disease (MJD1), we analyzed the CAG
repeat sizes of 1036 single sperm from six individuals with Machado- Joseph
disease (MJD). The segregation ratio between single sperm with an expanded
allele and those with a normal allele is significantly different (P
<0.0001) from the expected 1:1 segregation ratio, which demonstrates
segregation distortion of expanded alleles in male meiosis. In single sperm
from individuals with the [expanded (CAG)n- CGG]/[normal (CAG)n-GGG]
genotype, significantly greater instability of the CAG repeat was observed
compared with single sperm from individuals with the [expanded
(CAG)n-CGG]/[normal (CAG)n-CGG] genotype (F-test, P <0.001). These
findings in single sperm confirm non-Mendelian transmission of the MJD1
gene and the effect of the intragenic CGG/GGG polymorphism on the
intergenerational instability of the CAG repeats in the MJD1 gene, which
have been observed in clinical and genetic studies. Our results indicate
similarities and dissimilarities between MJD and Huntington's disease or
myotonic dystrophy in terms of the inter-allelic interaction, segregation
distortions and size distribution of trinucleotide repeats in mutant
alleles. Further study is required to determine whether there is a common
mechanism underlying the instability of the triplet repeats in 'triplet
repeat diseases'.
相似文献
70.
Igarashi S; Takiyama Y; Cancel G; Rogaeva EA; Sasaki H; Wakisaka A; Zhou YX; Takano H; Endo K; Sanpei K; Oyake M; Tanaka H; Stevanin G; Abbas N; Durr A; Rogaev EI; Sherrington R; Tsuda T; Ikeda M; Cassa E; Nishizawa M; Benomar A; Julien J; Weissenbach J; Tsuji S 《Human molecular genetics》1996,5(7):923-932
Machado-Joseph disease (MJD) is an autosomal dominant neurodegenerative
disorder caused by unstable expansion of a CAG repeat in the MJD1 gene at
14q32.1. To identify elements affecting the intergenerational instability
of the CAG repeat, we investigated whether the CGG/GGG polymorphism at the
3' end of the CAG repeat affects intergenerational instability of the CAG
repeat. The [expanded (CAG)n-CGG]/[normal (CAG)n- GGG] haplotypes were
found to result in significantly greater instability of the CAG repeat
compared to the [expanded (CAG)n- CGG]/[normal (CAG)n-CGG] or [expanded
(CAG)nGGG]/[normal (CAG)n-GGG] haplotypes. Multiple stepwise logistic
regression analysis revealed that the relative risk for a large
intergenerational change in the number of CAG repeat units (< -2 or >
2) is 7.7-fold (95% CI: 2.5-23.9) higher in the case of paternal
transmission than in that of maternal transmission and 7.4-fold (95% CI:
2.4-23.3) higher in the case of transmission from a parent with the
[expanded (CAG)n-CGG]/[normal (CAG)n-GGG] haplotypes than in that of
transmission from a parent with the [expanded (CAG)n-CGG]/[normal
(CAG)n-CGG] or [expanded (CAG)n- GGG]/[normal (CAG)n-GGG] haplotypes. The
combination of paternal transmission and the [expanded (CAG)n-CGG]/[normal
(CAG)n-GGG] haplotypes resulted in a 75.2-fold (95% CI: 9.0-625.0) increase
in the relative risk compared with that of maternal transmission and the
[expanded (CAG)n-CGG]/[normal (CAG)n-CGG] or [expanded (CAG)n- GGG]/[normal
(CAG)n-GGG] haplotypes. The results suggest that an inter- allelic
interaction is involved in the intergenerational instability of the
expanded CAG repeat.
相似文献