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101.
It has been described that tumor progression has many similarities to inflammation and wound healing in terms of the signaling processes involved. Among biological responses, angiogenesis, which is necessary for tumor progression and metastasis, is a common hallmark; therefore, tumor blood vessels have been considered as important therapeutic targets in anticancer therapy. We focused on pentraxin 3 (PTX3), which is a marker of cancer‐related inflammation, but we found no reports on its expression and function in tumor blood vessels. Here we showed that PTX3 is expressed in mouse and human tumor blood vessels based on immunohistochemical analysis. We found that PTX3 is upregulated in primary mouse and human tumor endothelial cells compared to normal endothelial cells. We also showed that PTX3 plays an important role in the proliferation of the tumor endothelial cells. These results suggest that PTX3 is an important target for antiangiogenic therapy.  相似文献   
102.
4-1BB (CDw 137), a member of the tumor necrosis factor receptor (TNFR) superfamily, is a costimulatory receptor primarily expressed on activated T cells. It has been shown that the administration of agonistic anti-4-1BB monoclonal antibody (mAb) enhances tumor immunity and allogenic immune responses. Paradoxically, we found that the administration of anti-4-1BB mAb reduced the incidence and severity of inflammatory bowel disease. In this study, we investigated the effects of anti-4-1BB mAb in a murine intestinal inflammation model, which induced by the hapten reagent, 2,4,6-trinitrobenzene sulfonic acid (TNBS) and mimics immunologic characteristics of human Crohn's disease (CD). Colitis was induced by rectal administration of 2mg of TNBS in 35% ethanol using a vinyl catheter positioned 4cm from the anus. All mice were sacrificed 3 and 10 days after the TNBS administration. The disease activity index (DAI), histological changes of the colon and production of cytokines (IL-2, IL-4, IL-10 and IFN-gamma) were evaluated. The surface molecules of T cells in peripheral blood, spleen and mesenteric lymph nodes were analyzed by flow cytometry. When mice were treated with anti-4-1BB mAb, improvement in both wasting and histopathologic signs of colonic inflammation was observed. The increase a number of splenic CD4(+)CD25(+) T cells and decreased synthesis of the Th1 cytokine IL-2 also occurred. Interestingly, increased production of Th1 cytokine IFN-gamma and proportion of CD8(+) T cells were observed in mice treated with anti-4-1BB mAb in comparison to the colitic mice. These studies show, for the first time, that agonistic anti-4-1BB mAb can improve experimental colitis by reduction of IL-2 and augmentation of CD4(+)CD25(+) regulatory T cells. TNBS colitis is Th1-mediated and has similar histologic features and distribution of inflammation to CD. This study suggests that anti-4-1BB mAb therapy could be effective in the treatment of patients with CD.  相似文献   
103.
Cell type-specific involvement of RIG-I in antiviral response   总被引:34,自引:0,他引:34  
Toll-like receptors (TLRs) play an important role in antiviral response by recognizing viral components. Recently, a RNA helicase, RIG-I, was also suggested to recognize viral double-stranded RNA. However, how these molecules contribute to viral recognition in vivo is poorly understood. We show by gene targeting that RIG-I is essential for induction of type I interferons (IFNs) after infection with RNA viruses in fibroblasts and conventional dendritic cells (DCs). RIG-I induces type I IFNs by activating IRF3 via IkappaB kinase-related kinases. In contrast, plasmacytoid DCs, which produce large amounts of IFN-alpha, use the TLR system rather than RIG-I for viral detection. Taken together, RIG-I and the TLR system exert antiviral responses in a cell type-specific manner.  相似文献   
104.
Objective: Late preterm infants are still high risk for respiratory problems. The aim of this study was to identify risk factors associated with respiratory problems in Japanese late preterm infants.

Methods: In this retrospective multicenter study, we included singleton late preterm deliveries at 34+0/7–36+6/7 weeks of gestation. We excluded cases with congenital anomalies. We defined neonatal respiratory disorders (NRD) as the combination of the need for mechanical ventilation or the use of nasal continuous positive airway pressure. We examined the perinatal risk factors associated with NRD.

Results: We included 683 late preterm infants. We found that 13.7%, 6.8% and 2.6% of the infants with NRD were born at 34, 35 and 36 weeks of gestation, respectively. In a multivariate logistic regression analysis adjusting for confounders, the gestational age (GA) at birth (adjusted odds ratio 0.40 per week [95% confidence interval, 0.25–0.61]), cesarean birth (4.18 [2.11–8.84]), and a low Apgar score (33.3 [9.93–121.3]) were independent risk factors associated with NRD.

Conclusions: An earlier GA, cesarean delivery, and a low Apgar score are independent risk factors associated with NRD in singleton late preterm infants. Patients with late preterm deliveries exhibiting these risk factors should be managed in the intensive delivery setting.  相似文献   
105.
Jeon WJ  Lee EK  Joh SJ  Kwon JH  Yang CB  Yoon YS  Choi KS 《Virus research》2008,137(1):153-156
To explore the epidemiological link between infectious bursal disease virus (IBDV) in wild birds and domestic chickens in Korea, we examined 107 free-living wild birds, representing 7 species, that were found dead of apparent natural causes in Korea over the past two years for the presence of IBDV. Five birds were tested positive for IBDV by RT-PCR assay: black-billed magpie (n=1), mallard duck (n=2), bean goose (n=1) and white-fronted goose (n=1). IBDV was isolated from RT-PCR-positive tissues following chicken embryo inoculation. Sequence analysis of the VP2 gene indicated that all of the isolates from the wild birds encode amino acids A222, I242, I256, I294 and S299 of VP2, which are conserved among strains of very virulent IBDV (vvIBDV). Phylogenetic analysis revealed that the wild bird IBDV isolates are closely related to strains of vvIBDV. An IBDV isolate from a magpie showed 60% mortality in SPF chickens and severe bursal atrophy. The epidemiological implications of IBDV in free-living wild birds are discussed. To our knowledge, this is the first report of vvIBDV in free-living wild birds.  相似文献   
106.
Venous hemodynamic changes after the surgery of primary varicose veins were evaluated. (Materials and methods) We retrospectively analyzed 1,211 patients (1,407 limbs) who underwent surgery for primary varicose veins from 1994 to 2002. The venous hemodynamics were evaluated using air- plethysmography (APG) preoperatively and one month postoperatively in the viewpoints of ambulatory venous pressure (AVP), venous volume (VV), venous filling index (VFI), and ejection fraction (EF). (Results) The surgical modalities included 958 cases of greater saphenous vein high ligation (GSV HL) and stripping with varicosectomy (VS), 222 cases of short saphenous vein (SSV) HL and VS, 143 cases of external banding valvuloplasty of GSV and VS, and 44 cases using VNUS and VS. The reduction rate of VV was 20.9 +/- 14.1% in the GSV stripping group, 12.0 +/- 14.7% in the GSV valvuloplasty group, 18.3 +/- 16.1% in the VNUS group, and 20.6 +/- 15.9% in the SSV group. The reduction rate of VFI was 63.6 +/- 20.7% in the GSV stripping group, 38.8 +/- 40.9% in the GSV valvuloplasty group, 60.1 +/- 23.9% in the VNUS group, and 37.6 +/- 30.2% in the SSV group. The increasing rate of EF was 25.0 +/- 28.2% in the GSV stripping group, 21.0 +/- 30.0% in the GSV valvuloplasty group, 29.4 +/- 31.9% in the VNUS group, and 30.0 +/- 36.5% in the SSV group. The reduction rate of AVP was 25.4 +/- 32.2% in the GSV stripping group, -6.1 +/- 58.1% in the GSV valvuloplasty group, 28.4 +/- 38.5% in the VNUS group, and 14.1 +/- 49.0% in the SSV group. All of the patients showed improvements in venous hemodynamics by showing a decrease in VV, VFI, AVP, and an increase in EF. However, there was no difference in the change of venous hemodynamics according to the type of surgery.  相似文献   
107.
Vibrio parahaemolyticus is a gram-negative marine bacterium. A limited population of the organisms causes acute gastroenteritis in humans. Almost all of the clinical V. parahaemolyticus isolates exhibit beta-type hemolysis on Wagatsuma agar, known as the Kanagawa phenomenon (KP). KP is induced by the thermostable direct hemolysin produced by the organism and has been considered a crucial marker to distinguish pathogenic strains from nonpathogenic ones. Since 1996, so-called “pandemic clones,” the majority of which belong to serotype O3:K6, have caused worldwide outbreaks of gastroenteritis. In this study, we used a DNA microarray constructed based on the genome sequence of a pandemic V. parahaemolyticus strain, RIMD2210633, to examine the genomic composition of 22 strains of V. parahaemolyticus, including both pathogenic (pandemic and nonpandemic) and nonpathogenic strains. More than 86% of the RIMD2210633 genes were conserved in all of the strains tested. Many variably present genes formed gene clusters on the genome of RIMD2210633 and were probably acquired through lateral gene transfer. At least 65 genes over 11 loci were specifically present in the pandemic strains compared with any of the nonpandemic strains, suggesting that the difference between pandemic and nonpandemic strains is not due to a simple genetic event. Only the genes in the 80-kb pathogenicity island (Vp-PAI) on chromosome II, including two tdh genes and a set of genes for the type III secretion system, were detected only in the KP-positive pathogenic strains. These results strongly suggest that acquisition of this Vp-PAI was crucial for the emergence of V. parahaemolyticus strains that are pathogenic for humans.  相似文献   
108.
To develop protective immune responses against mucosal pathogens, the delivery route and adjuvants for vaccination are important. The host, however, strives to maintain mucosal homeostasis by responding to mucosal antigens with tolerance, instead of immune activation. Thus, induction of mucosal immunity through vaccination is a rather difficult task, and potent mucosal adjuvants, vectors or other special delivery systems are often used, especially in the elderly. By taking advantage of the common mucosal immune system, the targeting of mucosal dendritic cells and microfold epithelial cells may facilitate the induction of effective mucosal immunity. Thus, novel routes of immunization and antigen delivery systems also show great potential for the development of effective and safe mucosal vaccines against various pathogens. The purpose of this review is to introduce several recent approaches to induce mucosal immunity to vaccines, with an emphasis on mucosal tissue targeting, new immunization routes and delivery systems. Defining the mechanisms of mucosal vaccines is as important as their efficacy and safety, and in this article, examples of recent approaches, which will likely accelerate progress in mucosal vaccine development, are discussed.  相似文献   
109.
Partial trisomy 9q involving the duplication of band 9q22 is manifested by a constellation of symptoms including short stature, intellectual disability, microcephaly, pyloric stenosis, facial dysmorphism, and various defects of the heart, distal extremities, eyes, thyroid, and esophagus. In three family members with growth retardation, mild intellectual disability, and mild facial dysmorphism, array-based comparative genomic hybridization analyses showed a familial microduplication at 9q22.3. On the basis of the described functions of the duplicated genes, PTCH1 represents a candidate gene that may be responsible for the phenotypic findings, although the 14 other genes in this duplicated segment may also contribute to the phenotype. The current report provides evidence to support a specific phenotype associated with a 9q22.3 microduplication and confirm localization of a subset of the trisomy 9q phenotype to this chromosomal region.  相似文献   
110.
OBJECTIVE: To determine whether Malawi antiretroviral treatment (ART) clinics providing cotrimoxazole (CTX) prophylaxis had lower early mortality rates compared with clinics not providing CTX. METHODS: Retrospective cohort study of eleven ART clinics in Malawi that were or were not providing CTX. Medical record abstraction was performed for all patients (N = 1295) initiating ART between July 1 and December 15, 2005. At 5 ART sites, CTX was given to patients dosed at 960 mg daily or 480 mg twice a day (according to national guidelines). RESULTS: When all defaults (patients lost to follow-up for >90 days) were excluded from the analysis, the 6-month mortality rate was 10.7% in patients receiving ART at CTX clinics compared with 18.0% in those not at CTX clinics (6-month mortality risk reduction = 40.7%; P = 0.0013). Kaplan-Meier survival curves for patients receiving CTX and patients not receiving CTX were significantly different; survival differences were apparent as early as 40 to 45 days after initiation of ART. CONCLUSIONS: Patients receiving ART in Malawi at clinics offering CTX prophylaxis had significantly reduced mortality during the first 6 months of ART. This additional intervention may have the potential to improve the lives of patients on ART, because CTX is readily available and relatively inexpensive and can, in principle, be easily introduced into ART delivery programs.  相似文献   
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