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61.
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   
62.
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   
63.
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   
64.
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   
65.
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   
66.
67.
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   
68.
Ghrelin is a newly discovered orexigenic peptide originating from the stomach. However, its action in regulating the fed and fasted motor activity of the digestive tract is not fully understood. In the present study, we examined the effects of intracerebroventricular ( i.c.v. ) and intravenous ( i.v. ) injection of ghrelin on the physiological fed and fasted motor activities in the stomach and duodenum of freely moving conscious rats. i.c.v. and i.v. injection of ghrelin induced fasted motor activity in the duodenum in normal fed rats, while i.v. injection of ghrelin induced fasted motor activity in both the stomach and duodenum in vagotomized rats. The effects of i.c.v. and i.v. injected ghrelin were blocked by growth hormone secretagogue receptor (GHS-R) antagonist given by the same route and also blocked by immunoneutralization of neuropeptide Y (NPY) in the brain. The effects of i.v. injected ghrelin were not altered by i.c.v. injection of GHS-R antagonist in vagotomized rats. Injection of GHS-R antagonist blocked the fasted motor activity in both the stomach and duodenum in vagotomized rats but did not affect the fasted motor activity in normal rats. Low intragastric pH inhibited the effect of ghrelin. The present results indicate that ghrelin is involved in regulation of fasted motor activity in the stomach and duodenum. Peripheral ghrelin may induce the fasted motor activity by activating the NPY neurons in the brain, probably through ghrelin receptors on vagal afferent neurons. Once the brain mechanism is eliminated by truncal vagotomy, ghrelin might be primarily involved in the regulation of fasted motor activity through ghrelin receptors on the stomach and duodenum. The action of ghrelin to induce fasted motor activity is strongly affected by intragastric pH; low pH inhibits the action.  相似文献   
69.
BACKGROUND: Many drugs and the combinations of drugs are recommended for each treatment step in bronchial asthma. However, there are few issues examined about the optimal drug and combination of drugs in a long term prognosis. In this study, we investigated the optimal drugs and combinations of drugs from a point of view of prognosis. METHODS: One hundred and ninety four patients who visited our hospital for treatment from November, 2003 to October, 2004 and were managed according to GINA guideline were surveyed retrospectively. We compared the rate of step up and the frequency of urgent visit and urgent hospitalization in one year between drug groups in each treatment step. RESULTS: The rate of step up was significantly higher in leukotriene receptor antagonist (LTRA) group than in inhalation corticosteroid (ICS) group and theophylline group in Step 2. The frequency of urgent visit and urgent hospitalization was significantly higher in ICS+LTRA group than in ICS+theophylline group and ICS+long-acting beta 2-agonist (LABA) group in Step 3. CONCLUSION: There is a possibility that the prognosis becomes bad when we use LTRA in the practical treatment according to GINA guideline.  相似文献   
70.
Septic shock remains a serious disorder associated with highmortality. Accumulating evidence indicates that TNF is a majorand essential mediator of endotoxin shock. We report here thatadministration of an antibody against CD18 dramatically reducedendotoxin-induced shock inrabbits as revealed by preventionof severe hypotension, metabolic acidosis and a pathologicalchange suggestive of disseminated intravascular coagulationwith concomitant inhibition of elevation of plasma TNF activity.The anti-CD18 antibody also inhibited the hypotension inducedby administering recombinant TNF. Furthermore, an antibody againsta ligand for CD18 complexes, intercellular adhesion molecule-1,also prevented TNF-induced shock as well as endotoxin shockinrabbits. These observations suggest that adhesion of leukocytesto endothelium may be of primary importance in the action ofTNF as well as in the production of TNF in vivo and that theantibody against adhesion molecules could be of therapeuticbenefit in life-threatening septic shock in humans.  相似文献   
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