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71.
Superantigens stimulate T-cell-receptor Vbeta-selective T-cell proliferation accompanying the release of cytokines, which may eventually protect the host from microbial infections. We investigated here whether superantigens can rescue the host from lethal bacterial infection. Mice were pretreated with Staphylococcus aureus enterotoxin B (SEB) 1 and 2 days before bacterial infection, and the mortality of infected mice was assessed. SEB pretreatment protected mice from lethal infection with Listeria monocytogenes but not from lethal infection with Streptococcus pyogenes. This enhanced protection was also observed upon pretreatment with recombinant streptococcal pyrogenic exotoxin A. Furthermore, L. monocytogenes-specific delayed-type hypersensitivity (DTH) due to type 1 helper T (Th1) cells and the cytotoxicity of CD8(+) T cells were significantly enhanced after SEB administration and bacterial infection. Depletion of either CD4(+) T cells or CD8(+) T cells in SEB-pretreated mice completely abolished this protection. This phenomenon was ascribed to the elimination of L. monocytogenes-specific CD8(+) cytotoxic T lymphocytes (CTL). It was found that CD4(+) T cells contributed to the induction of the CTL populations. Furthermore, SEB pretreatment of heat-killed L. monocytogenes-immunized mice enhanced the protection from challenge of L. monocytogenes. Taken together, these results indicated that administrations of superantigens protected mice from infection with L. monocytogenes, which was dependent on the enhanced L. monocytogenes-specific CTL activity in the presence of CD4(+) T cells, and superantigens exhibited adjuvant activity in the immunization against intracellular pathogens.  相似文献   
72.
In order to study the relationship between personality and the development of diabetic retinopathy in patients with diabetes mellitus, diabetics with retinopathy (severe group) and sex-, age-, and duration-matched diabetics without complications were tested by psychological tests, and interviewed. The result of the Yatabe-Guilford personality test (Y-G) and Spielberger's State and Trait Anxiety Inventory revealed that subjects were emotionally and socially stable and well-adjusted types and less anxious in the severe group than in the mild group. The interview findings reveal that the severe group had neglected the medical treatment and the diet therapy for significantly longer periods of time and the incidence of a childhood parental separation was significantly higher in the severe group than in the mild group. Discussion focuses on the severe diabetics' coping behavior which is characterized by the neglect of medical treatment and diet therapy for extended periods of time, which in turn resulted in diabetic retinopathy and other complications. Such coping behavior is shown to be equivalent to that found in the alexithymic behavioral syndrome.  相似文献   
73.
To investigate cell surface antigens of activated human eosinophils using monoclonal antibodies, we established a murine anti-human eosinophil monoclonal antibody AE500 by immunizing with blood eosinophils from patients with idiopathic hypereosinophilic syndrome (HES) and characterized the reactivity to a variety of human leucocytes by a fluorescence-activated cell sorter. AE500 reacted with blood eosinophils and neutrophils in nine out of 11 patients with marked eosinophilia (greater than or equal to 2500/microliters) (seven with idiopathic eosinophilia including HES and two with asthma), but not with those in asthmatic patients with mild eosinophilia (n = 10) or in healthy subjects (n = 8). AE500 did not react with blood lymphocytes, monocytes or platelets. AE500 did not react with human myeloid or lymphoid cell lines, including eosinophilic leukemia cell lines EOL-1 and EOL-3. The reactivity of AE500 to blood eosinophils and neutrophils in patients with marked eosinophilia changed in relation to blood eosinophil counts and prednisolone therapy. In addition, the reactivity of AE500 to blood eosinophils was increased in three out of four AE500-positive eosinophils by the incubation of the cells with granulocyte-macrophage colony-stimulating factor (GM-CSF) at 37 degrees C for 30 min, but not with interleukin 3 or interleukin-5. These results suggest that the anti-eosinophil antibody AE500 detects a cell surface antigen expressed on blood granulocytes in a hypereosinophilic state. This anti-eosinophil antibody would be useful for analysing the mechanism of eosinophilia.  相似文献   
74.
A 69-year old man complaining of longstanding hearing loss and mild otorrhea was found to have a mass obliterating the external auditory canal and polypous tympanic mucosa with accompanying absence of the tympanic membrane and ossicular chain. Tumors excised from the external auditory canal and tympanum showed histologic features essentially characteristic of a carcinoid tumor: a ribbon or festoon arrangement of tumor cells, formation of anastomosing cords and glandular spaces, presence of numerous argyrophilic as well as argentaffin secretory granules within many of the tumor cells, and ultrastructur-al evidence of neurosecretory granules in the tumor cell cytoplasm. Immunohistochemically, the tumor was found to contain not only neuronal marker substances such as neuron-specific enolase, S 100 protein and chromogranin A, but also serotonin and multiple peptide hormones such as pancreatic polypeptide, glucagon, cholecystokinin and leucine-enkephalin. A review of the pathology of 17 previous cases of carcinoid of the middle ear suggested that this type of carcinoid may have a variegated hormone profile among carcinoids of foregut origin, and hormonally may resemble ileal carcinoid arising from the midgut, although their histogenetic origins may differ, because of frequent production of serotonin. Acta Pathol Jpn 42: 614–620, 1992.  相似文献   
75.
Summary Glomerular lesions in hereditary nephrotic mice (ICGN strain) were investigated by electron microscopy. The glomeruli of unaffected animals, which appeared normal by light microscopy, had developed an ultrastructural change in the glomerular capillary basement membrane (GCBM). There was a partial thickening of the GCBM with bilaminar splitting of the lamina densa and an electron-dense fibrillar material exhibiting cross-striations. In affected animals, light microscopy revealed a marked thickening of GCBM and an increase of mesangial matrix without cellular proliferaton. By electron microscopy, multilaminar splitting of the lamina densa in the thickened GCBMs and fusion of the epithelial foot processes were observed. In some severely affected animals, immune complex deposition was found in GCBM, but little if any was observed in other animals. In the end, the glomeruli were globally sclerosed. Our findings suggest that initial structural abnormalities in GCBM may play an important role in the onset and development of the disease, though subsequent events such as immune complex deposition would modify the disease.  相似文献   
76.
Leukocyte adhesion to vascular endothelial cells is an essential step in the development of inflammatory diseases. We have searched for inhibitors of leukocyte-endothelial cell adhesion that could be used as anti-inflammatory drugs and found that bruceine B (0.2 g/ml; 0.44 M) inhibited human neutrophil or T cell adhesion to tumor necrosis factor- (TNF) stimulated human umbilical vein endothelial cells (HUVEC). The inhibition of neutrophil adhesion to TNF-stimulated HUVEC by bruceine B was not derived from cytotoxic effects, as determined by measurement of the level of lactate dehydrogenase (LDH) activity in conditioned medium. The effect of bruceine B on neutrophil adhesion to HUVEC was not seen when the neutrophils were preincubated with bruceine B. However, inhibitory effects were evident when the HUVEC were preincubated with bruceine B. Bruceine B also inhibited neutrophil adhesion to lipopolysaccharide-stimulated HUVEC and T cell adhesion to TNF-stimulated HUVEC. These findings suggest that bruceine B may have anti-inflammatory activity.  相似文献   
77.
High-performance liquid chromatography was successfully used to separate hemagglutination-inhibiting immunoglobulin M (IgM) rubella virus antibody from IgG rubella virus antibody in human serum. The fractionation by high-performance liquid chromatography was as effective as sucrose density gradient centrifugation in separating IgM antibody from IgG antibody.  相似文献   
78.
79.
This study was designed to explore whether it was possible to evaluate the severity of VSD, PDA, and ASD by measuring brain natriuretic peptide (BNP) levels. We also investigated normal BNP levels in children to provide a baseline for our study. We measured BNP levels in 253 normal children, including 11 normal neonates, and in 91 VSD patients, 29 PDA patients, and 34 ASD patients. BNP levels showed no age-related differences in normal children (the mean value: 5.3 +/- 3.8 pg/ml). In the healthy neonates, BNP levels rose from 10.4 +/- 11.9 pg/ml in cord blood to 118.8 +/- 83.2 pg/ml on day 0, then fell to 15.3 +/- 7.8 pg/ml by day 7. In VSD and PDA patients, BNP levels correlated significantly with Qp/Qs, LVEDV, and peak RVP/LVP. In ASD patients, BNP levels correlated with Qp/Qs and RVEDV. Especially, in VSD patients, as an index corresponding to 1.5-2.0 of the Qp/Qs ratio, BNP levels of 20-35 pg/ml were found to be best with regard to both sensitivity and specificity. In the healthy neonates, BNP levels changed rapidly after birth. In VSD, PDA, and ASD patients, BNP levels were well-correlated with the severity of the disease. Especially, in VSD patients, it that appears BNP levels may be useful in evaluating surgical indications, with 20-35 pg/ml levels being the appropriate cut-off value.  相似文献   
80.
Summary The ascending and descending components of the medial forebrain bundle (MFB) were investigated by means of horseradish peroxidase (HRP) with a sensitive substrate. The HRP was injected iontophoretically into the MFB at various levels from the anterior commissure to the posterior hypothalamus. In order to prevent the diffusion of HRP to other brain areas, a double micropipette system was used. The descending components of the MFB are derived from (1) the anterior cingulate area, infra- or prelimbic area, and sulcal cortex, (2) the lateral septal nucleus and diagonal band, (3) the bed nucleus of the stria terminalis, (4) the paraventricular nucleus (5) the substantia innominata, (6) the amygdaloid complex (AM), (7) the ventromedial (VM) and dorsomedial (DM) hypothalamic nuclei, (8) the entopeduncular nucleus and (9) nucleus periventricularis stellatocellularis. The ascending components of the MFB originate in: (1) the medial preoptic nucleus, (2) the nucleus periventricularis stellatocellularis and rotundocellularis, (3) the posterior hypothalamic nucleus, (4) the parafascicular nucleus, (5) the ventral premammillary nucleus, (6) the substantia grisea periventricularis, (7) the lateral habenular nucleus, (8) the VM and DM, (9) the paratenial nucleus, (10) the AM and (11) the arcuate nucleus.Abbreviations used in Figures and Tables a nucleus accumbens - abl nucleus amygdaloideus basalis, pars lateralis - abm nucleus amygdaloideus basalis, pars medialis - ac nucleus amygdaloideus centralis - AC anterior cingulate area - al nucleus amygdaloideus lateralis - am nucleus amygdaloideus medialis - ar nucleus arcuatus - CC tractus corporis callosi - CSDV commissura supraoptica dorsalis, pars ventralis - DB diagonal band - DM nucleus dorsomedialis hypothalami - EP nucleus entopeduncularis - ha nucleus anterior hypothalami - hl nucleus lateralis hypothalami - hp nucleus posterior hypothalami - IL infralimbic area of frontal cortex - lh nucleus habenulae lateralis - LH1 medial forebrain bundle (MFB) at the level of commissura anterior - LH2 lateral preoptic area - LH3 MFB at the level of the nucleus anterior hypothalami - LH4 MFB at the level of the nucleus ventromedialis hypothalami - LH5 MFB at the level of the nucleus posterior hypothalami - MFB medial forebrain bundle - pf nucleus parafascicularis - PL prelimbic area of frontal cortex - pol nucleus preopticus lateralis - pom nucleus preopticus medialis - posc nucleus preopticus, pars suprachiasmatica - pt nucleus parataenialis - pv nucleus premamillaris ventralis - PV nucleus paraventricularis - pvs nucleus periventricularis stellatocellularis - pvr nucleus periventricularis rotundocellularis - SC sulcal cortex - SGPV substantia grisea periventricularis - SI substantia innominata - SL lateral septal nucleus - ST bed nucleus of stria terminalis - sum nucleus supramamillaris - TO tractus opticus - tmm nucleus medialis thalami, pars medialis - VM nucleus ventromedialis hypothalami The nomenclature used in this paper is according to König and Klippel's Stereotaxic Atlas (1967).  相似文献   
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