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81.
Toshiaki Maruyama Ichiro Saito Sachiko Miyake Hiroshi Hashimoto Kazuto Sato Hideo Yagita Ko Okumura Nobuyuki Miyasaka 《European journal of immunology》1993,23(9):2059-2065
Synovial T cells play a crucial role in the pathogenesis of rheumatoid arthritis (RA) synovitis. We have quantitatively analyzed the T cell receptor (TcR) variable (V) region gene repertoire of freshly isolated synovial fluid (SF) T cells, comparing it with that of peripheral blood (PB) T cells in RA. The TcR V gene repertoire of PB and SF T cells in RA and osteoarthritis was heterogeneous. In contrast, Vail in SF was expressed to a greater degree in three of five RA patients, and increased levels of Vp6, 1-3 were found in the SF of four of six RA, compared with paired PB. Of note, Vβ6, 1–3 was universally used in four RA patients with a disease duration of less than 10 years, irrespective of their HLA-DR types. This was in contrast to two other RA patients, suffering for more than 20 years, who showed different Vα and Vβ usages. β-chain sequence analysis in RA patients with a preference for Vβ6, 1–3 has shown that a few clones dominated in SF, whereas polyclonality was observed in PB. These findings suggest oligoclonal expansion of T cells in response to specific antigen(s) in the SF of these patients with RA of relatively short duration. Concomitant use of two hydrophobic amino acids, leucine and valine, in the Dβ region was noticeable among the predominant SF clones. These two amino acids might directly contact a peptide specific for the induction of synovitis in RA patients. TcR-directed therapy may, therefore, be useful for the treatment of early RA synovitis. 相似文献
82.
Isao Katayama Masaki Shimizu Myota Miura Masanobu Maruyama Masayuki Kobayashi Yuuichi Iino Masaru Izuo Susumu Wakatsuki 《Virchows Archiv : an international journal of pathology》1984,402(4):353-359
Summary In a study of 277 patients with breast carcinomas, the PAP immunoperoxidase method for demonstrating endogenous estrogen was correlated with the sucrose density gradient (SDG) assay and with histologic and clinical features. The results from the PAP method and SDG assay agreed in 59 of 84 patients (82.1%) on whom both methods were performed. Histologically, the PAP method was positive in 7 of 7 patients with non-invasive carcinomas, in 164 of 233 patients (70.4%) with common invasive ductal carcinoma, and in 21 of 22 of those with special histological types of invasive carcinomas not including Paget's disease, medullary or apocrine carcinoma, where only 5 of 14 were positive. Clinically, 15 of 18 patients with positive endogenous estrogen showed a response to endocrine therapy as opposed to 1 of 9 patients with a negative endogenous estrogen. The mean survival was 31.2 and 15.6 months, respectively for patients with positive and negative endogenous estrogen. Remission for longer than 2 years was seen more often in patients with positive endogenous estrogen. These results suggest a clinical utility of the present PAP method which, therefore, deserves a further trial as an alternative to histochemical methods aiming at the estrogen receptors.This work was supported by Grants-in Aid for Scientific Research from the Ministry of Education, Science, and Culture of Japan (No. 56480119).This paper was presented at the 72nd Annual Meeding of International Academy of Pathology (United States-Canadian Division), Atlanta, Georgia, March 1, 1983. 相似文献
83.
84.
Morioka Atsuo; Iwashiro Michihiro; Matsubayashi Yuji; Teramura Yasuhumi; Kuribayashi Kagemasa 《International immunology》1994,6(6):839-846
This study showed that non-MHC genes common to (DBA/2 H-2d)and (DBA/1 H-2q) gave rise to suppressor T (Ta) cells in thehybrid F1 mice between C57BL/6 (B6) strain in the antl-FBL-3tumor responses. FBL-3, a Friend virus-induced tumor cell lineof B6 mouse origin, is highly immunogenic as shown by findingsthat syngenelc and hybrid F1 mice with several other inbredstrains rejected up to 3 x 107 tumor cells inoculated s.c. andgenerated potent CTL responses after mixed lymphocyte tumorcell culture. In contrast to these mice, (B6 x DBA/2) and (B6x DBA/1)F1 mice did not reject the tumor as the tumor dosesincreased. Progressive tumor growth in these F1 mice was blockedby an I.p. Injection of cyclophosphamlde (250 mg/kg) on day10, but not on day 5, after tumor cell inoculation. Antl-CD4(GK1.5) mAb exerted similar therapeutic effects against tumorwhen given twice, between day 0 and 10, whereas the additionalinjection of antl-CD8 mAb enhanced the tumor growth in micethat otherwise rejected the tumor. Thus, In the response of(B6 x DBA/2)F, mice to FBL-3 tumor cells, CD4+ T8 seemed todown-regulate the immunologically mediated regression of thetumor produced by CD8+ CTL. This was evidenced by limiting dilutionculture analyses, which showed that the frequency of an FBL-3-speclflcCTL precursor in the (B6 x DBA/2)F1 mice that rejected the tumorwith antl-CD4 mAb was 7- to 9-fold higher than that in micein which the tumor regressed spontaneously. That more than onegene was involved in suppressor T cell induction was shown bythe tumor growth pattern in (B6 x DBA/2)F1 x B6 backcross andB6D2F2 mice. 相似文献
85.
Carnitine is a naturally occurring amino acid derivative that is involved in the transport of long-chain fatty acids to the mitochondrial matrix. There, these substrates undergo β-oxidation, producing energy. The major sources of carnitine are dietary intake, although carnitine is also endogenously synthesized in the liver and kidney. However, in patients on dialysis, serum carnitine levels progressively fall due to restricted dietary intake and deprivation of endogenous synthesis in the kidney. Furthermore, serum-free carnitine is removed by hemodialysis treatment because the molecular weight of carnitine is small (161 Da) and its protein binding rates are very low. Therefore, the dialysis procedure is a major cause of carnitine deficiency in patients undergoing hemodialysis. This deficiency may contribute to several clinical disorders in such patients. Symptoms of dialysis-related carnitine deficiency include erythropoiesis-stimulating agent-resistant anemia, myopathy, muscle weakness, and intradialytic muscle cramps and hypotension. However, levocarnitine administration might replenish the free carnitine and help to increase carnitine levels in muscle. This article reviews the previous research into levocarnitine therapy in patients on maintenance dialysis for the treatment of renal anemia, cardiac dysfunction, dyslipidemia, and muscle and dialytic symptoms, and it examines the efficacy of the therapeutic approach and related issues. 相似文献
86.
87.
Hypoxia-ischemic insult in neonatal rats induced slowly progressive brain damage related to memory impairment 总被引:4,自引:0,他引:4
Mishima K Ikeda T Aoo N Takai N Takahashi S Egashira N Ikenoue T Iwasaki K Fujiwara M 《Neuroscience letters》2005,376(3):194-199
The present study was designed to determine potential associations between the brain damage induced by hypoxic-ischemic (HI) insult and spatial learning impairment in an eight-arm radial maze task. We first determined the pathological outcomes after 2, 5, 9, and 17 weeks of recovery following the HI insult. The results show that the brain damage progressed from 2 up to 17 weeks of recovery. To clarify the time course of the brain damage changes, we investigated the histological changes of the same individual with magnetic resonance imaging (MRI) after 5, 9, and 57 weeks of recovery following the HI insult. The MRI changes were similar to the histological changes, and the brain damages were exacerbated in the contralateral hemisphere after 57 weeks of recovery following the HI insult. To investigate whether alteration in brain function was correlated with MRI and histological changes, the rats were made to find their way through an eight-arm radial maze was performed at either 7th or 16th weeks of recovery. According to the results, the spatial learning impairments of rats in the maze starting at 16 weeks of recovery were more severe than those at 7 weeks of recovery, indicating that the impairments were progressive and depended on the degree of brain damage. The results of the present study are the first demonstration that the evolutional and specific brain damage following the HI insult is slowly and progressively exacerbated to the contralateral hemisphere and rats who experience the HI are at risk for showing a late impairment of brain function. 相似文献
88.
The plantar hyperkeratotic skin lesion in a case of Richner-Hanhart's syndrome was investigated using ultrastructural examination. Light microscopic examination showed remarkable hyperkeratosis and some aberrant keratinocytes with multiple nuclei. On ultrastructural examination, some abnormal structures were seen in the affected keratinocytes: aggregations of tonofilaments and intracytoplasmic inclusions. The inclusions were needle shaped and were considered to be "crystal ghosts," presumably of tyrosine. The formation of tyrosine crystalline inclusions seems to be an important factor in the pathogenesis of the cutaneous lesions in Richner-Hanhart's syndrome. 相似文献
89.
Kanzaki L Maruyama K Fukushima T Tamezguerra R Trejoavila L Casseb J Neitzert E Macedo J 《International journal of oncology》1997,10(5):1021-1024
Human T lymphotropic virus type I(HTLV-I) has been implicated in various human diseases. Serum samples of 390 Brazilian Amazonians with cancer of various types were tested for HTLV-I antibodies by Gelatin particle agglutination test, Enzyme linked immunosorbent assay and Western blotting. Of 134 sera from patients with cancer of uterine cervix, 4 were positive by all the methods. Three of these were from non-transfused patients. DNA was extracted from 2 of 4 seropositive sera that gave strong reactions and were analyzed by PCR-SSCP for HTLV-I sequences. One was positive for all HTLV-I genes tested while the other one was positive for LTR and tax and negative for gag. In view of a possible pathway of the virus by sexual contact, the involvement of HTLV-I in cervical cancer warrants further studies. 相似文献
90.
To evaluate the effects of personal factors such as lifestyle and Thpe A behavior on the life-stress process, we analyzed data randomly collected from 428 metropolitan Tokyo residents. Path analysis techniques were implemented to examine the direct and indirect effects of lifestyle and the Type A behavior pattern between life events, subjective stress and depressive symptoms. The following results were obtained: 1. Persons with a healthy lifestyle perceived a lower subjective stress level. 2. Although females with a healthy lifestyle had fewer direct depressive symptoms, males with a healthy lifestyle had fewer indirect depressive symptoms due to alleviation of subjective stress. 3. Type A males perceived a lower subjective stress level and Type A females experienced more life events. It is suggested that mental health is modified not only by lifestyle but also by Type A behavior in the life-stress process. In particular, the preservation and promotion of a healthy lifestyle appear to reduce subjective stress and may be an important factor for the improvement of mental ill health. 相似文献