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91.
Haruyo Nakajima PhDa Satoshi Hachimuraa Shinya Nishiwakia Toshiyuki Katsuki MD PhDb Naoki Shimojo MD PhDb Akio Ametani PhDa Yoichi Kohno MD PhDb Shuichi Kaminogawa PhDa 《The Journal of allergy and clinical immunology》1996,97(6):1342-1349
To study cow’s milk allergy at the cellular level, we assessed the reactivity of peripheral blood mononuclear cells from patients allergic to cow’s milk to αs1-casein, which is one of the major allergens in cow’s milk. Proliferation of the cells to αs1-casein activation showed a rather weak response. Therefore to understand T-cell reactivity to αs1-casein in more detail, we prepared αs1-casein–specific T-cell lines from patients allergic to cow’s milk and established 26 T-cell lines. These T-cell lines could be classified into three groups by analyzing their surface marker expression: those containing predominantly CD4+CD8- T cells, those containing both CD4+CD8- and CD4-CD8+ T cells, and those containing predominantly CD4-CD8+ T cells. The CD8+ T cells were obtained at an unexpectedly higher frequency from the patients. These T-cell lines produced interferon-γ and IL-4. These results suggest that CD8+ T cells specific for αs1-casein and CD4+ T cells were primed by the stimulation with αs1-casein in patients allergic to milk and that both T cells may play a key role in the onset, progression of, or recovery from cow’s milk allergy. (J ALLERGY CLIN IMMUNOL 1996;97:1342-9.) 相似文献
92.
Extrarenal Wilms' tumor in the adult patient. A case report and review of the world literature 总被引:2,自引:0,他引:2
Y Fukutomi C Shibuya S Yamamoto F Okuno S Nishiwaki Y Kashiki Y Muto 《American journal of clinical pathology》1988,90(5):618-622
A case of an extrarenal Wilms' tumor arising in the retroperitoneal region of a 49-year-old male is reported. A review of the world literature indicates that the incidence of the tumor arising in the extrarenal region is extremely rare. A total of 14 cases have previously been reported, but the number of cases that occurred in adult patients is only 2. The clinical and pathologic features are briefly discussed. 相似文献
93.
Mei N Tamae K Kunugita N Hirano T Kasai H 《Environmental and molecular mutagenesis》2003,41(5):332-338
In order to improve 8-hydroxyguanine (8-OH-Gua) detection in DNA, we digested isolated DNA with nuclease P1 and analyzed for 8-hydroxydeoxyguanosine 5'-monophosphate (8-OH-dGMP) using a high-performance liquid chromatography system equipped with an electrochemical detector (HPLC-ECD). The amount of 8-OH-Gua in the DNA was expressed as the ratio of 8-OH-dGMP to deoxycytidine monophosphate (dCMP). Using this analysis, the background level of 8-OH-Gua in DNA from human lung carcinoma cells (A549) was several-fold lower than that obtained by a previous method. A549 cells were exposed to 20-60 Gy of gamma-radiation and an increase in 8-OH-Gua concentration was observed with increasing gamma-ray dose (0.3 residues per 10(7) dCMP per Gy). Moreover, by an immunohistochemical procedure using a commercial FITC-kit, 8-OH-Gua was clearly detected in A549 cells and the fluorescence intensity of cells with oxidative DNA damage increased with the doses of gamma-irradiation. Using an endonuclease nicking assay, we also found that gamma-rays decreased 8-OH-Gua repair activity. The results indicate that 8-OH-dGMP is a useful and sensitive marker for estimating oxidative damage in DNA. 相似文献
94.
Kimura's disease with unusual eosinophilic epithelioid granulomatous reaction: a finding possibly related to eosinophil apoptosis 总被引:1,自引:0,他引:1
We report and discuss a case of Kimura's disease with an unusual eosinophilic epithelioid granulomatous reaction. A 3-year-old Japanese boy with eosinophilia and a high concentration of IgE developed lymphadenopathy and multiple cervical masses. A lymph node biopsy demonstrated the infiltration of eosinophils in the stroma, which is consistent with the findings of Kimura's disease. Interestingly, a number of apoptotic eosinophils was detected in the infiltrating eosinophils. Multiple epithelioid granulomas with central eosinophilic abscesses and necrosis were also observed. Macrophages and giant cells had phagocytosed the apoptotic eosinophils at the edge of the granulomas. In situ terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) assay showed that the TUNEL-positive eosinophils were both in the macrophages and in the central eosinophilic abscesses of the granulomas. These findings suggest that the eosinophils had undergone an accelerated apoptosis in this case of Kimura's disease, and that the epithelioid granulomas were produced by phagocytosis of the apoptotic eosinophils by macrophages. 相似文献
95.
Activity-inducible protein Homer1a/Vesl-1S promotes redistribution of postsynaptic protein Homer1c/Vesl-1L in cultured rat hippocampal neurons 总被引:2,自引:0,他引:2
Inoue Y Honkura N Kato A Ogawa S Udo H Inokuchi K Sugiyama H Ogawa S 《Neuroscience letters》2004,354(2):143-147
In cultured rat hippocampal neurons, overexpression of Homer1a/Vesl-1S, an inducible protein upregulated by seizure or long-term potentiation, caused a reduction of punctate distribution of a postsynaptic protein Homer1c/Vesl-1L, without significant decrease in its total amount. Clusters of F-actin were also decreased. Treatments of cells with BDNF or a proteasome inhibitor, which cause increase in the expression level of endogenous Homer1a, also resulted in the reduction of Homer1c puncta. These results indicate that the accumulation of Homer1a, either exogenously expressed or endogenously induced, caused redistribution and dispersion of postsynaptic clusters of Homer1c and F-actin, suggesting an important role of Homer1a in synaptic remodeling. 相似文献
96.
Three-dimensional two-layer collagen matrix gel culture model for evaluating complex biological functions of monocyte-derived dendritic cells 总被引:4,自引:0,他引:4
Tasaki A Yamanaka N Kubo M Matsumoto K Kuroki H Nakamura K Nakahara C Onishi H Kuga H Baba E Tanaka M Morisaki T Katano M 《Journal of immunological methods》2004,287(1-2):79-90
Dendritic cell-like cells (Mo-DCs) generated from peripheral blood monocytes with interleukin-4 (IL-4) and granulocyte-macrophage colony-stimulating factor (GM-CSF) have been used as tools to treat cancer patients (DC-vaccines). Because Mo-DCs have multiple antigen presentation-related functions, including phagocytosis, migration, cytokine production, and T cell stimulation, establishment of a method for simultaneously evaluating the various functions of Mo-DCs is important. We developed a new in vitro three-dimensional two-layer collagen matrix culture model that consists of a collagen gel containing Mo-DCs as the lower layer and a collagen gel containing necrotic GCTM-1 tumor cells and/or T cells as the upper layer. We used this system to observe simultaneously multiple functions of Mo-DCs by phase-contrast or fluorescence microscopy and to assess IL-12 secretion during more than 2 weeks of culture. We also observed interactions between Mo-DCs and necrotic GCTM-1 or T cells on an individual cell basis by time-lapse videomicroscopy. In addition, we collected Mo-DCs from the collagen gels by collagenase treatment and analyzed the expression of antigen presentation-related molecules such as HLA-DR, CD80, CD83, and CD86 on Mo-DCs. This model may be a useful tool for evaluation of the various functions of Mo-DCs used as DC vaccines and for studies of the complex behaviors of Mo-DCs in vivo. 相似文献
97.
Koibuchi H Shibuya Y Kubo N Kawano M Itoh K 《Rinsho byori. The Japanese journal of clinical pathology》2002,50(10):992-999
Clinical microbiology laboratories in Japan have not yet established standards for selecting the most appropriate antimicrobial agents for testing and reporting antimicrobial susceptibility that are comparable to the performance standards of the National Committee for Clinical Laboratory Standards(NCCLS) in the United States of America. Selection of the most appropriate antimicrobial agents for testing and reporting was discussed by a working group(WG) consisting of medical physicians, surgeons, pharmacists, medical technologists and medical microbiologists. The WG agreed on the following basic criteria for the selection of antimicrobial agents: 1) the agent should be useful when screening various resistant bacteria, 2) the agent should serve as a useful guide for physicians and residents when selecting antimicrobial agents, and 3) the agent should be useful for controlling nosocomial infections and resistant bacteria. Clinically isolated microorganisms were classified into 7 groups based on susceptibility to antimicrobial agents. These groups were Staphylococcus spp. or Enterococcus spp., Streptococcus spp. or Haemophilus spp., enterobacteriae, glucose non-fermenting gram positive rods(NFRs), anaerobic bacteria, fungi and mycobacterium. After considering clinical and bacteriological evidence, the WG decided on several antimicrobial agents for testing in clinical microbiology laboratories in Jichi Medical School Hospital. For the NFR group, these were Piperacillin(PIPC), ceftazidime(CAZ), cefepime, imipenem, amikacin and levofloxacin(LVFX). For the enterobacteriae group, these were Amplicillin(ABPC), PIPC, aztreonam, CAZ and LVFX. For the Staphylococcus spp. or Enterococcus spp. group, these were oxacillin, ABPC, vancomycin and gentamicin. We concluded that the most appropriate antimicrobial agent for testing and reporting must be economical and agreed upon at the hospital level, although the ultimate selection must be based on the available clinical and bacteriological evidence. 相似文献
98.
99.
Naoki Horikawa Tomoyuki Suzuki Takaoki Uchiumi Tetsuji Minamimura Kazuhiro Tsukada Noriaki Takeguchi Hideki Sakai 《The Journal of physiology》2005,562(3):885-897
Increased release of thromboxane A2 (TXA2 ) has been shown to be involved in inflammatory bowel diseases. In the present study, we have investigated the effect of a stable TXA2 analogue (STA2 ) on the electrical parameters in isolated human colonic mucosa. In the human mucosa set between Ussing chambers, STA2 stimulated Cl− secretion in a concentration-dependent manner with an EC50 of 0.06 μ m . The STA2 -induced Cl− secretion was significantly inhibited by ONO-3708 (10 μ m ), a specific TXA2 receptor antagonist. The effect of STA2 (0.3 μ m ) was independent of the colonic segment from which the tissue was obtained, from caecum to rectum. Chromanol 293B, an inhibitor of the cAMP-dependent KvLQT1 channel, attenuated the STA2 -induced Cl− secretion in the human colonic mucosa (IC50 value 1.18 μ m ). We found that KvLQT1 mRNA and protein were expressed in all the tested segments of the human colon. The STA2 -induced Cl− secretion was significantly inhibited by 8-bromo-2'-monobutyryladenosine-3',5'-cyclic monophosphorothioate (50 μ m ), a membrane-permeant cAMP antagonist. STA2 (0.3 μ m ) significantly increased the intracellular cAMP levels and the short-circuit current via TXA2 receptor in a human colonic cell line. These results suggest that the TXA2 -induced Cl− secretion in the colon is mediated via the cAMP pathway in addition to the Ca2+ –calmodulin pathway which was previously reported. 相似文献
100.
Using transcranial magnetic stimulation (TMS), we examined whether sensory input from a finger affects activity of the ipsilateral primary motor cortex (M1) when human subjects hold a virtual object bimanually and whether this ipsilateral activation varies under different contexts. Subjects used both index fingers to hold two plates, which were subjected to unpredictable pulling loads from torque motors. Loads were delivered in a random sequence to either plate or concurrently to both, although the latter occurred most frequently. Finger forces vertical to the plates and surface electromyographs from the first dorsal interosseous muscles were recorded bilaterally during the task. TMS was sometimes applied over the finger area of the left M1 at variable times relative to load onset to examine cortical excitability. Strength of TMS was set around the active motor threshold of the right finger muscle while subjects waited for loading to the handheld plates. When one plate was singly loaded, the M1 contralateral to the loaded finger was activated, causing automatic force increases in the finger. In addition, the ipsilateral M1 was activated during such loading, associated with transient force increases in the contralateral nonloaded finger. Activations in the ipsilateral M1 were also observed during concurrent loading, when activations were stronger than those following single loading of the contralateral plate. Ipsilateral activations weakened when concurrent loading was less frequent. These results suggest interactions between bilateral sensorimotor cortices during bimanual coordinated movements, with strength varying by context. 相似文献