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81.
It has been demonstrated that in vivo T cell priming requires CD154-CD40 interaction, which is suggested to be critical in the induction of co-stimulatory activities on antigen-presenting cells (APC). In the current study, we demonstrate that in vivo administration of a high dose of a superantigen, staphylococcal enterotoxin A (SEA), could up-regulate B7-2 on most splenic APC independently of the CD154-CD40 interaction, followed by efficient expansion of SEA-reactive V(beta)3(+) T cells in CD154- or CD40-deficient mice. However, the CD154-CD40 interaction may be involved in SEA-mediated T cell activation, since a contribution of the CD154-CD40 interaction was observed when a lower dose of SEA was injected. CD154-independent T cell priming by SEA appeared also independent of the TRANCE-RANK pathway, which was shown to be capable of mediating CD154-independent activation of naive T cells during the infection of some viruses. These results indicate that SEA, which provokes rapid and efficient T cell responses without adjuvant, could utilize multiple CD154/TRANCE-independent pathways, to prime T cells. 相似文献
82.
Pancreatic adenocarcinoma is a common disease that is rarely cured. Surgical resection remains the only treatment modality that has a curative potential, although the majority of patients are unsuitable for resection at the time of diagnosis. Chemoradiation therapy prior to a pancreaticoduodenectomy ensures that a patient who undergoes a complete resection multimodality therapy, avoids a resection in patients who have a rapidly progressive disease, and allows radiation therapy to be given to well oxygenated cells before, surgical devasculation. This permits the chance of resection of an unresectable pancreatic cancer by downstaging. A patient with cytologic proof of localized adenocarcinoma of the pancreatic head received an intravenously chemoradiation (Taxol, 50 mg/m2 intravenously for 3 hours week on 5 cycles, of Gemcytabine 1000 mg/m2/day intravenously for 3 days week on 2 cycles, of 4500 cGy) with the intention of proceeding to a resection operation, restaging was performed by computed tomography, magnetic resonance imaging from 5 weeks every months due to ongoing decreasing of tumor size after the chemoradiation. At laparotomy, the patient didn't have suspected metastatic disease, the tumor size was 2 X 3 cm on the pancreas head and was infiltrating into the portal vein for about 3 cm length on right side. A pancreaticoduodenectomy along with a portal vein and superior mesenteric vein resection was done and then reconstruction of a vascular anastomosis by using the right side of the internal jugular vein. Perioperative complications didn't occur. In conclusion, preoperative chemoradiation of a localized advanced pancreatic tumor has no added risk to the operative complications and the prospects for resectability are enhanced. 相似文献
83.
Rodríguez-Niedenführ M Vázquez T Choi D Parkin I Sañudo JR 《Clinical anatomy (New York, N.Y.)》2003,16(3):197-203
Supernumerary humeral heads of the biceps brachii muscle were found in 27 (15.4%) of 175 cadavers. They were bilateral in five cadavers and unilateral in 22 (8 left, 14 right), giving a total of 32 examples in 350 arms (9.1%). Depending on their origin and location, the supernumerary heads were classified as superior, infero-medial, and infero-lateral humeral heads. Previous studies were reviewed using this classification. The infero-medial humeral head was observed in 31 of 350 (9%) arms and was therefore the most common variation. The superior humeral head was observed in five (1.5%). The infero-lateral humeral head was the least common variation, observed only in one (0.3%) of 350 arms. A biceps brachii with three heads was observed in 27 of 350 (7.7%) arms and with four heads in five (1.4%) arms. 相似文献
84.
Identification of surface-exposed B-cell epitopes recognized by Haemophilus influenzae type b P1-specific monoclonal antibodies.
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H Panezutti O James E J Hansen Y Choi R E Harkness M H Klein P Chong 《Infection and immunity》1993,61(5):1867-1872
A panel of P1 synthetic peptides was synthesized to map the surface-exposed epitopes of Haemophilus influenzae type b outer membrane protein P1 recognized by three murine monoclonal antibodies (MAbs 7C8, 3E12, and 6B1). By using peptide-specific enzyme-linked immunosorbent assays, MAbs 6B1, 7C8, and 3E12 were shown to recognize distinct epitopes localized within residues 60 to 88, 165 to 193, and 400 to 437 of mature P1, respectively. Since MAb 7C8 was shown previously to be protective against certain H. influenzae type b subtypes in the infant rat model of bacteremia, its cognate epitope was further characterized by using truncated peptide analogs. Fine mapping of the 7C8 epitope by competitive inhibition studies revealed that it was localized within residues 184 and 193. 相似文献
85.
The novel cytokine p43 stimulates dermal fibroblast proliferation and wound repair 总被引:3,自引:0,他引:3
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Park SG Shin H Shin YK Lee Y Choi EC Park BJ Kim S 《The American journal of pathology》2005,166(2):387-398
The multifunctional cytokine p43 acts on endothelial and immune cells to control angiogenesis and inflammation. In this report, we describe an additional activity of p43 that specifically promotes fibroblast proliferation and wound repair. In skin wound regions from mice, tumor necrosis factor-alpha induced p43 expression and secretion from macrophages recruited to the site. p43 also promoted fibroblast proliferation through its 146-amino acid N-terminal domain as revealed by deletion mapping. This p43-induced fibroblast proliferation was mediated by extracellular signal-regulated kinase (Erk). Depletion of endogenous p43 in mice by gene disruption retarded wound repair, whereas exogenous supplementation of recombinant human p43 to the wound area stimulated dermal fibroblast proliferation, collagen production, and wound closure. Thus, we have identified a novel p43 activity involving the stimulation of fibroblast proliferation, which could be applied therapeutically to aid wound repair. 相似文献
86.
87.
Lee J Kim MS Park C Jung EB Choi DH Kim TY Moon SK Park R 《Immunopharmacology and immunotoxicology》2004,26(1):17-28
This study is designed to investigate the effect of morphine on glutamate-induced toxicity of primary rat neonatal astrocytes. Glutamate decreases the intracellular GSH level, and thereby induces cytolysis of astrocytes and C6 glial cells accompanied by apoptotic features. Glutamate-induced cytotoxicity is protected by morphine and antioxidants such as GSH and NAC, whereas MK-801, an antagonist of glutamate receptor NMDA does not protect astrocytes against glutamate toxicity. Also, morphine antagonist, naloxone, as well as selective ligands for opioid receptor subtypes, including DAMGO, DPDPE, and U69593, do not inhibit the protective effect of morphine on glutamate-induced cytotoxicity. Morphine significantly prevents the depletion of GSH by glutamate and thereby inhibits the generation of H2O2 in a dose-dependent manner. Furthermore, morphine prevents the change of mitochondrial permeability transition by glutamate. Taken together, we suggest that morphine protects the primary rat neonatal astrocytes from glutamate toxicity via modulation of intracellular redox status. 相似文献
88.
Kam KM Luey CK Tsang YM Law CP Chu MY Cheung TL Chiu AW 《Journal of clinical microbiology》2003,41(10):4502-4511
Two hundred twenty isolates of Vibrio cholerae O1 and O139 collected from 1994 to 2002 in Hong Kong were analyzed by pulsed-field gel electrophoresis (PFGE). Chromosomal DNAs from all V. cholerae isolates in agarose plugs were digested with the restriction enzyme NotI, resulting in 20 to 27 bands. Sixty distinctive PFGE patterns in the range of 10 to 300 kb were noted among 213 isolates typeable by PFGE. By comparing the common PFGE patterns obtained from four well-defined outbreaks of V. cholerae O1 and O139 with those obtained from other, epidemiologically unrelated isolates during the study period, indistinguishable and similar PFGE patterns were identified, indicating their close relatedness, in agreement with the results of epidemiological investigations. Heterogeneous PFGE patterns (with four to six banding differences), however, were identified among strains that were imported from other parts of Asia, including Indonesia, India, and Pakistan. Correlations with epidemiological information further support the usefulness of PFGE as an epidemiological tool in laboratory investigations of suspected outbreaks. Standardization of PFGE methodology will allow international comparison of fingerprint patterns and will form the basis of a laboratory network for tracking V. cholerae. 相似文献
89.
Sun Hee Choi Do Kyun Kim Young Yoo Jinho Yu Young Yull Koh 《Annals of allergy, asthma & immunology》2007,98(2):128-133
BACKGROUND: In asthmatic individuals, airway sensitivity and maximal airway response are increased. Airway sensitivity is usually evaluated by measuring the provocation concentration of inhaled methacholine or histamine that causes a decrease in forced expiratory volume in 1 second of 20% (PC20). The percentage decrease in forced vital capacity at the PC20 (deltaFVC) has been proposed as a surrogate marker for maximal airway response. Individuals with allergic rhinitis and no clinical evidence of asthma frequently exhibit airway hypersensitivity. OBJECTIVE: To compare the deltaFVC between patients with allergic rhinitis and mild asthmatic patients with a similar degree of airway hypersensitivity. METHODS: A retrospective analysis of methacholine challenge test data from 72 children with allergic rhinitis and airway hypersensitivity (methacholine PC20 < 16 mg/mL) (rhinitis group) and from 72 children with mild atopic asthma matched to the rhinitis group regarding the methacholine PC20 (asthma group). The deltaFVC was calculated on the concentration-response curve to methacholine. RESULTS: The mean +/- SD deltaFVC was significantly lower in the rhinitis group (15.0% +/- 3.6%) vs the asthma group (17.4% +/- 5.3%) (P = .002). There was no significant correlation between the deltaFVC and PC20 in the rhinitis (r = -0.101; P = .41) and asthma (r = -0.023; P = .85) groups when 2 patients with PC20 less than 1 mg/mL were excluded from each group. CONCLUSIONS: Patients with allergic rhinitis and airway hypersensitivity had a significantly lower deltaFVC than methacholine PC20-matched mild asthmatic patients, suggesting that the level of maximal airway response in patients with allergic rhinitis is lower than that in mild asthmatic patients with a similar degree of airway hypersensitivity. 相似文献
90.
Down-regulation of transforming growth factor-beta gene expression by antisense oligodeoxynucleotides increases recombinant interferon-gamma-induced nitric oxide synthesis in murine peritoneal macrophages. 总被引:1,自引:0,他引:1
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Increasing evidence indicates that the production of nitric oxide (NO) by inducible NO synthase (iNOS) is tightly regulated. Transforming growth factor-beta (TGF-beta) is a family of multifunctional peptides secreted during macrophage activation, but several lines of evidence suggest that TGF-beta is selectively suppressive for macrophage NO production. We therefore reasoned that a strategy employing oligodeoxynucleotides (ODN) complementary to TGF-beta mRNA (antisense ODN) might increase NO production in interferon-gamma (IFN-gamma) treated murine peritoneal macrophages. To evaluate this concept, we tested the effects of antisense ODN targeted to TGF-beta mRNA (25-mer ODN complementary to TGF-beta mRNA sequences) by introducing them into the medium of cultured macrophages. Phosphorothioation of ODN was employed to retard their degradation. Antisense ODN had no effect on NO production by itself, whereas IFN-gamma alone had a modest effect. When antisense ODN were used in combination with IFN-gamma, there was a marked cooperative induction of NO production. These effects of antisense ODN were associated with decreased TGF-beta expression in activated macrophages. However, sense ODN had no effect. Adding anti-TGF-beta antibodies to the IFN-gamma-treated macrophages mimicked the positive effect of antisense ODN on NO production. In addition, the effects of either antisense ODN or anti-TGF-beta antibodies were blocked by adding exogenous TGF-beta in cultured macrophages. These results indicate that the generation of TGF-beta by activated macrophages provides a self-regulating mechanism by which the temporal and perhaps spatial production of NO, a reactive and potentially toxic mediator, can be finely regulated. 相似文献