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1.
2.
K. Arima Minako Nakamura Nobuhiko Sunohara Masafumi Ogawa Midori Anno Yoko Izumiyama Shigeo Hirai Kazuhiko Ikeda 《Acta neuropathologica》1997,93(6):558-566
Coiled bodies and interfascicular threads are conspicuous white matter abnormalities of brains of patients with progressive
supranuclear palsy (PSP). Both structures are argyrophilic and immunoreactive for the microtubule-binding protein tau. This
report concerns the ultrastructural localization of interfascicular threads and their relationship to coiled bodies in five
PSP patients. We showed for the first time that abnormal tubules with a 13- to 15-nm diameter and fuzzy outer contours were
the common structures of coiled bodies in the oligodendroglial perikarya and of interfascicular threads. Moreover, the tubules
were immunolabeled by anti-tau antibodies. The abnormal tau-positive tubules of interfascicular threads were located in the
inner loop of the myelin sheath. Our study further indicated that the thread-like structures in the white matter comprised,
at least in part, oligodendroglial processes, and that they were also present in gray matter. We consider that the formation
of coiled bodies in the perikarya and of interfascicular threads represents a common cytoskeletal abnormality of the oligodendroglia
of PSP patients. Moreover, even though the white matter alterations of PSP resemble those of corticobasal degeneration, there
are certain ultrastructural differences in the abnormal oligodendroglial tubules of the two diseases.
Received: 4 October 1996 / Accepted: 6 December 1996 相似文献
3.
Evidence for the involvement of a plasma kallikrein-kinin system in the immediate hypotension produced by endotoxin in anaesthetized rats. 总被引:4,自引:4,他引:0 下载免费PDF全文
M. Katori M. Majima R. Odoi-Adome N. Sunahara Y. Uchida 《British journal of pharmacology》1989,98(4):1383-1391
1. In vitro incubation of normal rat plasma with endotoxin from E. coli (3-10 mg ml-1) in the incubation mixture) caused a dose-dependent increase in levels of free kinin and plasma kallikrein in the presence of o-phenanthroline, together with a mirror-image, dose-dependent decrease in the residual levels of the precursors, plasma prekallikrein and high-molecular-weight kininogen. Low-molecular-weight kininogen levels were not modified. 2. Intravenous injection of endotoxin (3-30 mg kg-1) into the femoral vein of anaesthetized rats resulted in dose-dependent hypotension. In blood collected up to 15 min after injection, the levels of prekallikrein and high-molecular-weight kininogen in plasma were decreased while levels of the active forms, plasma kallikrein and free kinin, showed a transient increase in the blood 1 min after administration of endotoxin. 3. A degradation product of bradykinin, des-Phe8-Arg9-bradykinin, as measured by a newly developed enzyme immunoassay, was detectable up to 5 min after administration of endotoxin. 4. Intravenous infusion of soybean trypsin inhibitor inhibited both the formation of bradykinin and des-Phe8-Arg9-bradykinin and the initial hypotension. 5. It can be concluded from our results that plasma prekallikrein is activated in the blood immediately after administration of endotoxin to rats and that bradykinin is a major cause of the immediate hypotension. 相似文献
4.
Ikuo Konishi M.D. Kanako Nanbu M.D. Masaki Mandai M.D. Yuko Tsuruta M.D. Nobuhiko Kataoka M.D. Yasushi Nagata M.D. Takahide Mori M.D. 《Gynecologic oncology》1998,70(3):365-371
Objective.To identify the clinicopathological and chemoresistant factors predicting the response to neoadjuvant chemotherapy and the patient prognosis in high-risk cervical carcinomas.Methods.We retrospectively reviewed 47 patients with locally advanced or bulky cervical carcinoma treated with two courses of intraarterial infusion of cisplatin, doxorubicin, mitomycin C, and 5-fluorouracil (5-FU), followed by radical hysterectomy at our hospital between 1988 and 1995. Expressions of the chemoresistance-related proteins, such as P-glycoprotein, glutathioneS-transferase π (GST-π), and proliferating cell nuclear antigen (PCNA) in the tumor cells, were examined by immunohistochemistry using pretreatment biopsy specimens. These results were compared with the chemotherapeutic response, which was evaluated by magnetic resonance imaging (MRI) and histopathology. Outcome of the patients was also studied.Results.Chemotherapeutic effect of either complete (CR) or partial (PR) response on MRI was obtained in 36 of the 47 (86%) patients. Poor response to chemotherapy was significantly correlated with P-glycoprotein expression (P< 0.005) and low PCNA labeling (P< 0.05), but not GST-π expression in the tumor cells. Independent prognostic factors for patient survival were parametrial involvement and lymph node metastasis. Neither the expression of GST-π nor PCNA was correlated with the patient survival.Conclusion.Assessment of the expression of P-glycoprotein and PCNA is potentially useful for the prediction of tumor response to neoadjuvant chemotherapy for cervical carcinomas. 相似文献
5.
We investigated the relative effects of 0.5, 1.0, 1.5, 2.0 MAC halothane and enflurane, and concurrent noxious stimulus on hepatic blood flow and oxygen consumption in 14 mongrel dogs randomly divided into groups of seven each. Hepatic arterial and portal venous blood flow (HABF and PVBF, respectively) were measured continuously using ultrasonic transit time flow meter. Mean arterial blood pressure (MAP), cardiac index (CI), hepatic oxygen supply, and hepatic oxygen consumption (H
O
2) were measured. Halothane significantly deceased HABF, but not PVBF in a dose dependent manner. Enflurane did not affect HABF and PVBF significantly. MAP and CI decreased in both groups, with halothane producing more marked decreases than enflurane. H
O
2 did not change with enflurane, but did with halothane, producing significant differences, with halothane being greater at 1.5, 2.0 MAC. A noxious stimulus only caused minor change in blood flow. The results suggest that liver blood flow and oxygen consumption are affected differently by halothane and enflurane and that halothane has a stronger tendency to cause an imbalance between liver oxygen supply and consumption than dose enflurane.(Masaki E, Yasuda N, Tanifuji Y et al.: Effect of halothane and enflurane on hepatic blood flow and oxygen consumption in dogs. J Anesth 3: 118–122, 1989) 相似文献
6.
Eye infections caused by adenovirus (Ad) often result in nosocomial infections and community epidemics with significant rates of morbidity. No antiviral agent effective against Ad is yet available for clinical use. Therefore, early diagnosis is still the mainstay for patient management and the prevention of epidemics. A multiplex PCR assay based on amplification of a combination of the fiber and hexon genes which can identify the six important oculopathogenic serotypes of Ads (Ad serotype 3[Ad3], Ad4, Ad7, Ad8, Ad19, and Ad37) in a single-tube amplification reaction was developed. Ad serotypes could be distinguished by the different amplicon sizes. The assay correctly identified prototype strains as well as isolates in clinical specimens. In comparison with a previously described PCR-restriction fragment polymorphism method, our assay gave unequivocal results for clinical specimens. Our multiplex PCR has the potential to serve as a rapid and cost-effective tool for the typing of important ocular Ads. 相似文献
7.
Gao HZ Kobayashi K Tabata A Tsuge H Iijima M Yasuda T Kalkanoglu HS Dursun A Tokatli A Coskun T Trefz FK Skladal D Mandel H Seidel J Kodama S Shirane S Ichida T Makino S Yoshino M Kang JH Mizuguchi M Barshop BA Fuchinoue S Seneca S Zeesman S Knerr I Rodés M Wasant P Yoshida I De Meirleir L Abdul Jalil M Begum L Horiuchi M Katunuma N Nakagawa S Saheki T 《Human mutation》2003,22(1):24-34
Classical citrullinemia (CTLN1), a rare autosomal recessive disorder, is caused by mutations of the argininosuccinate synthetase (ASS) gene, localized on chromosome 9q34.1. ASS functions as a rate-limiting enzyme in the urea cycle. Previously, we identified 32 mutations in the ASS gene of CTLN1 patients mainly in Japan and the United States, and to date 34 different mutations have been described in 50 families worldwide. In the present study, we report ASS mutations detected in 35 additional CTLN1 families from 11 countries. By analyzing the entire coding sequence and the intron-exon boundaries of the ASS gene using RT-PCR and/or genomic DNA-PCR, we have identified 16 novel mutations (two different 1-bp deletions, a 67-bp insertion, and 13 missense) and have detected 12 known mutations. Altogether, 50 different mutations (seven deletion, three splice site, one duplication, two nonsense, and 37 missense) in 85 CTLN1 families were identified. On the basis of primary sequence comparisons with the crystal structure of E. coli ASS protein, it may be concluded that any of the 37 missense mutations found at 30 different positions led to structural and functional impairments of the human ASS protein. It has been found that three mutations are particularly frequent: IVS6-2A>G in 23 families (Japan: 20 and Korea: three), G390R in 18 families (Turkey: six, U.S.: five, Spain: three, Israel: one, Austria: one, Canada: one, and Bolivia: one), and R304W in 10 families (Japan: nine and Turkey: one). Most mutations of the ASS gene are "private" and are distributed throughout the gene, except for exons 5 and 12-14. It seems that the clinical course of the patients with truncated mutations or the G390R mutation is early-onset/severe. The phenotype of the patients with certain missense mutations (G362V or W179R) is more late-onset/mild. Eight patients with R86H, A118T, R265H, or K310R mutations were adult/late-onset and four of them showed severe symptoms during pregnancy or postpartum. However, it is still difficult to prove the genotype-phenotype correlation, because many patients were compound heterozygotes (with two different mutations), lived in different environments at the time of diagnosis, and/or had several treatment regimes or various knowledge of the disease. 相似文献
8.
Kiyosumi Shibata Fumitaka Kikkawa Akihiko Nawa Koji Tamakoshi Nobuhiko Suganuma Yutaka Tomoda 《Clinical & experimental metastasis》1997,15(6):612-619
Ovarian cancer cells disseminate by attachment to the peritoneal mesothelial cell surface of the abdominal cavity. We therefore investigated the influence of conditioned medium (CM) from human peritoneal tissues and mesothelial cells on the secretion of matrix metalloproteinases (MMPs) by ovarian cancer cells. The molecular weights of MMPs stimulating factors derived from human peritoneal tissues and mesothelial cells were estimated using microconcentrators with various cut-off membranes. Human peritoneal tissues were obtained from 12 surgical patients, and mesothelial cells were isolated from three peritoneal specimens. Exposure to CM from peritoneal tissue caused a concentration-dependent increase of the MMP-2 and MMP-9 bands in CM from NOM1 ovarian cancer cells, as shown by zymography. There was a significant difference in the increase of MMP-2 and MMP-9 (2.46-fold and 7.14-fold, respectively, at 0.4mg/ml protein; P < 0.005). CM from mesothelial cells also significantly increased the secretion of MMP-9 by NOM1 cells. The molecular size of possible MMP-9-stimulating factors secreted by peritoneal tissues and mesothelial cells was above M 100000. Further, CM of peritoneal tissues and mesothelial cells also induced the invasiveness of NOM1 cells. These findings suggest that mesothelial cells may secrete some factors which predominantly induce the MMP-9 production and increase invading cell numbers. 相似文献
9.
Nobuhiko Okamoto 《American journal of medical genetics. Part A》2019,179(5):822-826
Okamoto syndrome is characterized by severe intellectual disability, generalized hypotonia, stenosis of the ureteropelvic junction with hydronephrosis, cardiac anomalies, and characteristic facial gestalt. Several patients have been reported. The basic mechanism of Okamoto syndrome has not been clarified. Au–Kline syndrome is a new syndrome due to loss‐of‐function variants in the HNRNPK (heterogeneous nuclear ribonucleoprotein K) gene. A new patient with Okamoto syndrome visited our hospital. We noticed that the patient had features overlapping with Au–Kline syndrome. We studied the HNRNPK gene by Sanger sequencing, and identified a novel splicing variant. We suggest that Okamoto syndrome is identical to Au–Kline syndrome. 相似文献
10.
Okamoto N Toribe Y Nakajima T Okinaga T Kurosawa K Nonaka I Shimokawa O Matsumoto N 《Journal of human genetics》2002,47(10):0556-0559
Chromosome 1p36 deletion syndrome is characterized by hypotonia, moderate to severe developmental and growth retardation,
and characteristic craniofacial dysmorphism. Muscle hypotonia and delayed motor development are almost constant features of
the syndrome. We report a 4-year-old Japanese girl with 1p36 deletion syndrome whose muscle pathology showed congenital fiber
type disproportion (CFTD) myopathy. This is the first case report of 1p36 deletion associated with CFTD. This association
may indicate that one of the CFTD loci is located at 1p36. Ski proto-oncogene −/− mice have phenotypes that resemble some of the features observed in patients with 1p36 deletion syndrome.
Because fluorescent in situ hybridization analysis revealed that the human SKI gene is deleted in our patient, some genes in 1p36, including SKI proto-oncogene, may be involved in muscle hypotonia and delayed motor development in this syndrome.
Received: March 4, 2002 / Accepted: July 7, 2002 相似文献