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101.
Cell biology and pathology of liver sinusoidal endothelial cells 总被引:9,自引:0,他引:9
Katsuhiko Enomoto Yuji Nishikawa Yasufumi Omori Takuo Tokairin Masayuki Yoshida Naoto Ohi Takuya Nishimura Youhei Yamamoto Qinchang Li 《Medical Electron Microscopy》2004,37(4):208-215
Growing evidence revealed that liver sinusoidal endothelial cells (SEC) play several important roles in physiology and pathology of the liver. It has been well understood that their structural characteristics, such as the membrane sieve and lack of basement membrane, facilitate direct contact of soluble and insoluble serum substances with hepatic parenchymal cells, resulting in enhancement of hepatic metabolic activity. In addition, SEC is now regarded as a member of the scavenger endothelial cells, which have potential to eliminate a variety of macromolecules from the blood circulation by receptor-mediated endocytosis. It is reported that molecules preferentially eliminated by SEC are denatured or modified proteins such as advanced glycation end products, extracellular matrix components including hyaluronic acid, and some lipoproteins. The nature of the scavenger receptors corresponding to these molecules remains to be clarified. Recently, it was noted that SEC has an antigen-presenting function similar to dendritic cells. Taken together, it is suggested that SEC, cooperating with Kupffer cells and hepatic dendritic cells, may partake of immunoregulatory functions in the liver. SEC also plays a pivotal role in the pathological process of ischemia-reperfusion injury following liver surgery and liver transplantation. Thus, it is of importance to elucidate the mechanisms of apoptosis and proliferation of SEC. Recent results on the regulation of growth and apoptotic signaling of SEC are discussed. 相似文献
102.
Shioiri T Kojima M Hosoki T Kitamura H Tanaka A Bando T Someya T 《Journal of affective disorders》2004,82(3):395-401
BACKGROUND: Although panic disorder (PD) is suggestive of autonomic nervous system dysfunction, especially in the cardiovascular autonomic system (CAS), the results in many previous studies are still controversial. Using a new physiological index which could well reflect emotional reaction to visual stimuli (Yoshizawa, M., Sugita, N., Tanaka, A., Abe, K., Yambe, T., Nitta, S., 2001. Quantiatative Physioligical Evaluation of Three Dimensional Images. The Seventh International Conference on Virtual Systems and Multumedia, 25-27.), we studied momentary changes in the CAS in patients with PD during audiovisual stimulation (AS) as mental loading. METHODS: During AS, exposed to a video of imaginary experiences such as driving a motor vehicle or diving into the sea, blood pressure (BP) and heart rate (HR) were measured in 12 remitted patients with PD and 19 age- and sex-matched normal controls (NC). We used the maximum cross-correlation coefficient (rho(max)) from the BP to the HR, whose frequency components were limited to around 0.1 Hz. RESULTS: The rho(max) was an available index which could detect the momentary changes in the CAS during AS in both groups. The two-way ANOVA disclosed significant group and time effects on the rho(max). The momentary response to emotional stimuli in the PD patients was slower than that in the NC subjects. LIMITATIONS: Antidepressants have a potential impact on the autonomic variables in this study. CONCLUSIONS: These findings suggest that there may be a dysfunction of the CAS in remitted PD patients and that the dysfunction may be one of the trait markers of PD. To confirm these findings, however, further studies with a large sample size are required. 相似文献
103.
Hirata I Hioki Y Toda M Kitazawa T Murakami Y Kitano E Kitamura H Ikada Y Iwata H 《Journal of biomedical materials research. Part A》2003,66(3):669-676
Since complement activation is recognized as a common response of the host defense system when an artificial medical device is applied to a patient, great effort has been devoted to studies on the interaction of the complement system with artificial materials. However, some uncertainties remain, partially because of the lack of well characterized surfaces and suitable analytic methods for study of the surface phenomena that occur on artificial materials under physiologic conditions. In this study, we employed self-assembled monolayers (SAMs) and the surface plasmon resonance (SPR) technique to study interactions of the serum complement with well characterized surfaces. Self-assembled monolayers carrying various concentrations of hydroxyl groups were prepared using 11-mercapto-1-undecanol (C11-OH) and one of n-nonanethiol, n-dodecanethiol, and n-hexadecanethiol. The amount of NHS deposition on the SAMs increased with increasing C11-OH content of the SAMs, and the amount of anti-C3b antibody immobilization formed on the NHS deposition layers increased with increasing C11-OH content of the SAMs. These results clearly demonstrate that a large amount of C3b, produced through the activation of the complement system, binds covalently to and is adsorbed by hydroxyl-group-rich surfaces. The combination of SAMs and the SPR technique is suitable for studying the interaction of the complement system with solid surfaces, and the results should give basic information needed for a rational design of biocompatible surfaces on synthetic materials. 相似文献
104.
A 62-year-old Japanese woman with RA received an eradication therapy against Helicobacter pylori in November 1999. Eight weeks later, successful eradication was confirmed by negative results for rapid urease test, pathologic findings, and a fall in anti-H. pylori IgG antibody titer. During the course, parameters for RA activity were exacerbated: C-reactive protein 1.1-4.2 mg/dL, rheumatoid arthritis precipitation antigen 2560-5120 dils., erythrocyte sedimentation rate 52-123 mm/h, and complements CH50 50 to over 60 U/mL. Lansbury index increased from 70% to 105%. Two more weeks later, the patient noticed right shoulder pain. She also complained of bilateral gonalgia two months later, and physical examination revealed increased fluid in the knee joints. Prednisolone was required to control the disease activity. The results of this case suggested that RA patients might experience a deleterious effect on the disease activity following H. pylori eradication possibly through disruption of the established oral tolerance against stress protein such as mycobacterial heat shock protein 65. 相似文献
105.
Detection of group C rotaviruses in Tokyo 总被引:8,自引:0,他引:8
H Ushijima H Honma A Mukoyama T Shinozaki Y Fujita M Kobayashi M Ohseto S Morikawa T Kitamura 《Journal of medical virology》1989,27(4):299-303
Four human group C rotaviruses were detected in Tokyo in 1987 and 1988 during a survey over 7 years. Among the four rotaviruses, two electrophoretic patterns were indicated by polyacrylamide gel electrophoretic (PAGE) analyses. Clinical symptoms, signs, family history, and patients' ages varied. Group C rotaviruses were found also in other parts of Japan in 1988. It was suspected that group C rotaviruses would continue to spread throughout Japan within the near future. 相似文献
106.
A simplified method for the preparation of EAC14 intermediate cells using human serum treated with methylprednisolone 总被引:2,自引:0,他引:2
The inhibitory effect of methylprednisolone 21-succinate ester (MPS) on the activities of complement components in human serum was studied by incubating human serum with various concentrations of MPS at 37 degrees C for 30 min and then measuring the residual activity of each component in human serum. The formation of EAC1 and EAC14 by C1 and C4 respectively, were only weakly inhibited by MPS at a final concentration of 10 mg/ml. In contrast, the same concentration of MPS completely inhibited the capacity of C2, C3, C5 and C6-9 to induce respective succeeding intermediates. On the basis of these findings a simplified method was devised for the preparation of EAC14 intermediates using human serum pretreated with MPS. 相似文献
107.
A low molecular weight inhibitor of the alternative complement pathway. I. Its isolation from human urine and the reaction mechanism. 总被引:1,自引:0,他引:1
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A low molecular inhibitor (LMW-INH) of the alternative pathway activation was isolated form healthy human urine. Its molecular weight was slightly higher than 1000. LMW-INH inhibited C3 convertase formation in fluid phase, on sheep erythrocytes and on zymosan particles. In contrast with beta 1H globulin LMW-INH showed no effect on the C3b binding site for B, and it inhibited the activation of CVF.B complex by D only when LMW-INH was simultaneously present with D. These results indicate that the reaction mechanism of LMW-INH is different from that of beta 1H globulin. 相似文献
108.
109.
Tissue factor pathway inhibitor can interact with platelets 总被引:3,自引:0,他引:3
Nishioka T Yokota M Hino M Tsuda I Tatsumi N 《Journal of immunological methods》2002,266(1-2):181-184
Tissue factor pathway inhibitor (TFPI) regulates the extrinsic pathway of blood coagulation. However, there is no report on interaction between TFPI and platelets other than that by Tsuji, who found that whole blood anticoagulated with TFPI exhibited remarkable decrease in platelet count. Our study revealed that washed platelets suspended in modified Tyrode's buffer (8 mM CaCl2) containing TFPI exhibit platelet aggregation. However, platelets aggregation was observed without TFPI, but its increase and intensity were slow and weak, compared to that in the presence of TFPI. This aggregation was inhibited by anti-CD41 (anti-GPIIb) antibody. This finding suggested that TFPI promotes platelet aggregation. 相似文献
110.
Miura T Goto M Hosoya N Odawara T Kitamura Y Nakamura T Iwamoto A 《Journal of medical virology》2003,70(4):497-505
Mitochondrial DNA (mtDNA) of peripheral blood mononuclear cells (PBMCs) collected from Human immunodeficiency virus 1 (HIV-1)-infected patients and healthy controls were measured longitudinally using real-time polymerase chain reaction to evaluate the effects of antiretroviral agents on mtDNA synthesis in vivo and to assess the value of monitoring mtDNA in PBMCs to predict adverse events amongst these patients. MtDNA levels in PBMCs were significantly decreased in treatment-naive HIV-1-infected patients compared with healthy people. MtDNA levels were not only significantly correlated with CD4(+) T-cell count, but also inversely correlated with HIV-1 viral load. MtDNA levels in untreated patients and healthy controls were stable during the period of observation. On the other hand, amongst patients treated with regimens containing AZT/3TC or d4T/3TC, mtDNA increased during treatment and recovered to levels comparable to healthy controls. In contrast, mtDNA decreased immediately after the initiation of an AZT/ddC-containing regimen. We did not find a correlation between mtDNA levels and changes in clinical parameters. There was no significant difference in mtDNA levels between patients with and those without lipoatrophy. Furthermore, there was no obvious difference in mtDNA levels amongst those patients exhibiting signs and symptoms of peripheral neuropathy. In conclusion, the decrease in mtDNA levels in PBMCs amongst HIV-1-infected patients and its amelioration by antiretroviral therapy may suggest the influence of direct effects on mitochondria or mtDNA by HIV-1 infection. Further investigations are needed to elucidate the mechanisms contributing to decreased mtDNA and the value of mtDNA measurement in the care of HIV-1-infected individuals. 相似文献