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11.
An inhibitor of the motility of demembranated spermatozoa has been shown to be present in human seminal plasma. This seminal plasma motility inhibitor (SPMI) was purified to apparent homogeneity and tested on intact human spermatozoa. Motility parameters of spermatozoa incubated with the sperm motility inhibitor were evaluated with the video automated Cell Soft system. SPMI decreased the percentage of motile spermatozoa in a dose-dependent manner and motility was completely blocked in the presence of 1600 units/ml. Sperm velocity and beat/cross frequency showed a similar progressive decrease as the inhibitor was augmented. However, linearity was essentially not affected. The effects of SPMI on the percentage of motile spermatozoa increased with the time of contact between the inhibitor and spermatozoa. After 120 min., the IC50 was 35% lower than that observed at five min. The presence of seminal plasma did not prevent the inhibitory effects of the seminal plasma factor on sperm motility parameters. On the contrary, a potentiating effects was observed. The data suggest that the SPMI could play a significant role in cases of infertility caused by asthenospermia. 相似文献
12.
13.
K Baba M Yajima N Ohyama T Iwamoto T Osada T Inoue T Shinagawa 《Hinyokika kiyo. Acta urologica Japonica》1990,36(12):1467-1470
Metastatic tumor of the penis is uncommon and only 95 cases have been reported in Japan. A 70-year-old man, who had squamous cell carcinoma of the lower pharynx, complained of urethral induration. Biopsy was performed and pathological diagnosis was metastatic tumor of penis originating from the lower pharynx. Although partial response in tumor size was noted by irradiation therapy, the patient died of multiple metastases in the 4th month after the diagnosis. This case is the first report of metastatic penile tumor originating from the lower pharynx. 相似文献
14.
S Arai C Arai M Fujimaki Y Iwamoto M Kawarada Y Saito Y Nomura T Suzuki 《Journal of comparative pathology》1991,104(4):439-441
Cutaneous tumour-like growths were observed on the face and other areas of the body surface of young Chilean flamingos. In the cells of these lesions, avian pox-specific cytoplasmic inclusion bodies were observed by light microscopy and virus particles were detected under an electron-microscope. It was diagnosed as avian pox. 相似文献
15.
Identification of an ion channel-forming motif in the
primary structure of CFTR, the cystic fibrosis chloride channel. 下载免费PDF全文
M Oblatt-Montal G L Reddy T Iwamoto J M Tomich M Montal 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(4):1495-1499
Synthetic peptides with sequences representingputative transmembrane (M) segments of CFTR (the cystic fibrosis transmembraneconductance regulator) were used as tools to identify the involvement of suchsegments in forming the ionic pore of the CFTR Cl- channel. Peptides withsequences corresponding to M2 and M6 form anion-selective channels afterreconstitution in lipid bilayers. In contrast, peptides with the sequences ofM1, M3, M4, and M5, or peptides of the same amino acid composition as M2 and M6but with scrambled sequences, do not form channels. Conductive heterooligomersof M2 and M6 exhibit a single channel conductance of 8 pS (in 0.15 M KCl) and a95% selectivity for anions over cations, properties that emulate both theconductance and the selectivity of the authentic CFTR channel. Theidentification of sequence-specific motifs that account for key functionalattributes of the CFTR channel suggests that such modules may representfundamental units of function and are plausible constituents of the pore-formingstructure of the CFTR Cl- channel. 相似文献
16.
Akio Sakamoto Tatsuya Yoshida Hidetaka Yamamoto Yoshinao Oda Masazumi Tsuneyoshi Yukihide Iwamoto 《Journal of orthopaedic science》2007,12(4):361-365
Background Congenital pseudarthrosis of the tibia (CPT) is frequently, but not always, associated with neurofibromatosis type 1 (NF1).
Double inactivation of the NF1 gene has been reported to be the pathogenesis of CPT in NF1 cases.
Methods We analyzed the loss of heterozygosity (LOH) of the NF1 gene in cases of CPT with NF1 to examine whether double inactivation was seen in the case. In addition to morphological analysis,
immunoexpression of differentiation markers was examined.
Results and discussion The tibia tapered with the zone phenomenon from mature to immature bone with osteoblastic rimming, resembling osteofibrous
dysplasia. Osteosclerotic bowed bone with a small number of osteoclasts suggested dysfunction of bone remodeling. Fibrous
tissue at the site of pseudarthrosis was associated with the periosteum and demonstrated myofibroblastic differentiation accompanied
by massive cartilage formation, suggesting some misdirection during the differentiation of periosteum to myofibroblasts or
chondrocytes. LOH of the NF1 gene locus was not seen in fibrous tissue. This result suggests that CPT is not accompanied by double inactivation in every
NF1 case. 相似文献
17.
S. Iwamoto E. Kajii T. Omi T. Kamesaki Y. Akifuji S. Ikemoto 《European journal of haematology》1993,50(5):286-291
Abstract: A patient who represented acute hemolytic crisis was studied. Analysis of the erythrocyte membrane proteins by SDS-PAGE revealed a deficiency of band 4.2. In the family, the sister of the patient who had been clinically normal was also shown to be deficient in band 4.2. Binding studies showed that the propositus' membranes were able to bind normal band 4.2 protein as much as control. It was suggested that the binding sites for the protein were prepared on the membrane. We analyzed the band 4.2 cDNA of the propositus and detected a mutation that changes a codon for alanine to one for threonine at residue 142. Band 4.2 exon III of genomic DNA which included the mutation site was amplified and sequenced directly in the family members, and it was revealed that only the homozygotes of the mutation allele manifested band 4.2 deficiency and the parents, who were heterozygotes, showed normal amounts of band 4.2. Recently, the same mutation was reported as Protein 4.2NIPPON in another 4 cases (Bouhassira et al. Blood 1992: 79: 1846–1854). This study supports the hypothesis that this mutation is the pathogenetic cause of band 4.2 deficiency and not a polymorphism. 相似文献
18.
Yoshihiro Katagiri Kazuhide Mabuchi Tadanori Itakura Kohji Naora Kikuo Iwamoto Yoshimasa Nozu Shun-ichi Hirai Nobumasa Ikeda Toshio Kawai 《Cancer chemotherapy and pharmacology》1989,24(4):238-242
Summary Physicochemical properties of two types of adriamycin preparation, suspensions and emulsions prepared for i.a. chemotherapy of hepatocellular cacinoma, were investigated. A suspension was prepared by dispersing adriamycin directly into the lipid contrast medium, Lipiodol, whereas an emulsion was obtained by emulsifying an aqueous solution of adriamycin into Lipiodol. The dispersibility of the drug in each preparation was examined microscopically. The chemical stability of and drug release from the preparation were determined by high-performance liquid chromatography and spectrophotometry, respectively. The suspension was then given to ten patients with primary hepatocellular carcinoma. The suspension maintained good dispersibility without coagulation of drug particles, whereas coalescence of aqueous droplets and the resultant phase separation occurred 4 h after preparation of the emulsion. Both preparations maintained the initial drug content for at least 1 week at room temperature. The release of adriamycin was more prolonged in the suspension than in the emulsion. After i.a. administration of the suspension, a selective accumulation of Lipiodol in the tumor and decrease in serum -fetoprotein (AFP) levels were found in most patients. A significant amount of adriamycin was still detected in hepatic speciments resected from two patients 1 and 2 months after treatment. These findings suggest that the adriamycin-Lipiodol suspension may be a useful preparation for targeting chemotherapy to hepatocellular carcinoma. 相似文献
19.
Genes predisposing to autoimmunity augment constitutive major histocompatibility complex class II-associated presentation of the self-antigen IgG2a in vivo 下载免费PDF全文
The self-antigen IgG2ab is poorly presented to a gamma2ab 435-451-reactive I-Ad-restricted T-cell hybridoma unless available in high concentrations or targeted to Fcgamma- or complement receptors. Environmental factors, probably the extent of microbial challenge, profoundly influence the constitutive gamma2ab/I-Ad presentation in IgCHb, H-2d mice. Here we report also a strong genetic impact. Constitutive presentation was highly efficient in spleen and thymus of (NZB x BXSB)F1 mice, which inherit a predisposition to develop lupus. Presentation correlated with disease progression and the serum levels of IgG2ab and IgG2ab complement factor 3 complexes. The finding that constitutive presentation was by far most efficient in males indicated that it was augmented by the Y chromosome-linked autoimmune acceleration Yaa gene. In line with previous data for healthy mice, constitutive gamma2ab/I-Ad presentation was most pronounced in the adherent spleen cell fraction and improved by further enrichment for dendritic cells. Notably, however, whereas in normal mice the gamma2ab determinant was undetectable on B cells lacking surface IgG2ab, such B cells contributed considerably to constitutive presentation in (NZB x BXSB)F1 hybrids. Presumably this resulted from complement receptor-mediated internalization of IgG2ab-containing immune complexes formed in lupus. These data add to the evidence that B cells with self-reactive receptors, known to exist in the mature repertoire, may present non-cognate foreign antigen to anti-foreign helper T lymphocytes and thus differentiate into autoantibody-secreting cells, and might likewise account for the polyclonal B-cell activation characteristic of several autoimmune syndromes. 相似文献
20.
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