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991.
Matrix metalloproteinase 9 (MMP9) gene has been shown to be involved in the pathogenesis of allergic rhinitis (AR) and asthma. Previous studies suggested that single-nucleotide polymorphisms (SNPs) of the MMP9 gene conferred a risk for childhood asthma. However, whether the SNPs confer a risk for AR has not been previously investigated. The objective of this study was to investigate whether SNPs of the MMP9 gene are associated with risk of seasonal AR (pollinosis), perennial AR and allergen sensitization. A total of 670 school children were recruited in Japan and genotyped for functional polymorphism in the promoter (-1590C/T: rs3918242) and three amino-acid substitutions (R297Q: rs17576; P574R: rs2250889; R668Q: rs17577). Serum levels of total and specific IgE were determined. Disease status and other clinical characteristics of the subjects were investigated using a questionnaire. Associations between the MMP9 SNPs and both AR and serum IgE levels were evaluated. -1590C/T showed significant association with cedar pollinosis (corrected P (Pcor)=0.039). R668Q was in strong linkage disequilibrium (LD) with -1590C/T and showed significant association with cedar pollinosis (Pcor=0.023) and serum cedar pollen-specific IgE level (Pcor=0.022). A haplotype associated with -1590T and 668Q showed a significant association with cedar pollinosis, orchard grass pollinosis and cedar pollen-specific IgE (Pcor=0.0012, Pcor=0.0059 and Pcor=0.0041, respectively). R297Q and P574R were in weak LD with the rest of the SNPs and did not show significant association with disease. Compared with wild-type MMP9 protein (279R-574P-668R), a variant enzyme (279R-574P-668Q) that showed association with pollinosis had lower activity. However, lower enzyme activity was not associated with disease risk because another variant (279Q-574R-668R) showed lower enzyme activity but was not associated with pollinosis. The -1590T allele and its corresponding haplotype was associated with higher promoter activity and with pollen-specific IgE levels and pollinosis, suggesting that -1590C/T may have more impact on sensitization and disease development than R668Q. Our results suggest that the MMP9 gene confers susceptibility to cedar pollinosis in Japanese children. The MMP9 gene may be associated with pollinosis through sensitization processes.  相似文献   
992.
Sepsis was induced by well-controlled cecal ligation and puncture (CLP) in macrophage inflammatory protein 1alpha (MIP-1alpha)/CCL3 knockout (CCL3(-/-)) and severe combined immunodeficiency (SCID) mice. CCL3(-/-) mice and their littermates (CCL3(+/+) mice) treated with anti-CCL3 monoclonal antibodies were susceptible (0-20% survival) to CLP-induced sepsis, and CCL3(-/-) mice supplemented with recombinant (r)CCL3 (250 ng/mouse) and CCL3(+/+) mice were resistant (70-80% survival). The resistance of SCID mice to CLP was markedly improved by the rCCL3 administration (88% survival), and SCID mice treated with saline were shown to be middling resistant to the same CLP (45% survival). However, the resistance of SCID-M mice (SCID mice depleted of the macrophage function) to CLP was not improved by the rCCL3 administration (11% survival), and 41% of SCID-M mice reconstituted with normal peritoneal macrophages and 79% of SCID-M mice inoculated with CCL3-treated peritoneal macrophages survived. In addition, the resistance of SCID-MN mice (SCID mice depleted of functional macrophages and neutrophils) to CLP was improved by the inoculation of CCL3-treated macrophages (78% survival), and all of SCID-MN mice inoculated with CCL3-treated neutrophils died. CCL3 is shown to be essential to the host resistance against bacterial sepsis. Macrophages but not neutrophils are highlighted as the major effector cells when protective innate immunities against sepsis are improved by CCL3.  相似文献   
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Severe experimental infections with Cryptosporidium parvum have been reported in immunocompromised animals such as SCID mice (mice without functional T cells and B cells). In a C. parvum infection with 1 x 10(6) oocysts/mouse in SCID beige (SCIDbg) mice (SCID mice lacking functional NK cells), oocyst shedding was first demonstrated 18 days after infection. However, shedding was shown as early as 3 days after the same infection in SCIDbgMN mice. All of the SCIDbgMN mice died within 16 days of C. parvum infection, while 100% of the SCIDbg mice exposed to the parasite survived. SCIDbgMN mice are SCIDbg mice depleted of functional macrophages (Mphi) and neutrophils (PMN), suggesting that the severity early after C. parvum infection is strongly influenced by the functions of Mphi and PMN. All SCIDbgMN mice orally infected with a lethal dose of C. parvum survived after they were inoculated with Mphi from SCIDbg mice exposed to C. parvum (CP-Mphi) or resident Mphi previously cultured with PMN from C. parvum-infected SCIDbg mice (CP-PMN). However, all SCIDbgMN mice inoculated with CP-PMN alone or resident Mphi alone died after C. parvum infection. CP-Mphi were identified as classically activated Mphi (M1Mphi), and CP-PMN were characterized as PMN-I. In in vitro studies, resident Mphi converted to M1Mphi after transwell cultivation with CP-PMN. These results indicate that the resistance of SCIDbg mice early after C. parvum infection is displayed through the function of M1Mphi which are converted from resident Mphi influenced by CP-PMN (PMN-I).  相似文献   
997.
Kabuki syndrome is characterized by a variable degree of intellectual disability, characteristic facial features, and complications in various organs. Many variants have been identified in two causative genes, that is, lysine methyltransferase 2D (KMT2D) and lysine demethylase 6A (KDM6A). In this study, we present the results of genetic screening of 100 patients with a suspected diagnosis of Kabuki syndrome in our center from July 2010 to June 2018. We identified 76 variants (43 novel) in KMT2D and 4 variants (3 novel) in KDM6A as pathogenic or likely pathogenic. Rare variants included a deep splicing variant (c.14000‐8C>G) confirmed by RNA sequencing and an 18% mosaicism level for a KMT2D mutation. We also characterized a case with a blended phenotype consisting of Kabuki syndrome, osteogenesis imperfecta, and 16p13.11 microdeletion. We summarized the clinical phenotypes of 44 patients including a patient who developed cervical cancer of unknown origin at 16 years of age. This study presents important details of patients with Kabuki syndrome including rare clinical cases and expands our genetic understanding of this syndrome, which will help clinicians and researchers better manage and understand patients with Kabuki syndrome they may encounter.  相似文献   
998.
The aims of this study were to evaluate the efficacy of long-term interferon (IFN) monotherapy on hepatocellular carcinoma (HCC) in patients who showed no virological response to the first course of IFN therapy, define predictive factors for HCC in patients on long-term IFN monotherapy, and evaluate the clinical impact of amino acid (aa) substitutions in the hepatitis C virus (HCV)-1b core region on HCC rate. This retrospective study included 494 consecutive treatment-naive patients infected with HCV-1b who failed to achieve sustained virological response after ≥24-week IFN monotherapy. Of 494 patients, 113 (22.9%) received another course of ≥48-week IFN monotherapy (additional-IFN group), while the remaining 381 (77.1%) received no such therapy (no-additional-IFN group), and 10 years have elapsed since the end of the first IFN monotherapy. The cumulative HCC rate was significantly higher in the no-additional-IFN group than additional-IFN group, and in those with aa substitutions in the core region of Gln70(His 70) and Met 91 than those with Arg 70 and/or Leu 91. Multivariate analysis identified stage of liver fibrosis, liver enzymes, age, treatment group, aa substitution in the core region, low-density lipoprotein cholesterol (LDL-cholesterol), and gender as determinants of HCC, and that additional IFN treatment significantly lowered the cumulative rate of HCC, even in patients with cirrhosis. In conclusion, long-term IFN monotherapy reduces the risk of HCC, even in patients with cirrhosis. Substitution of aa at position 70 and/or 91 in the core region and lipid metabolism are important predictors of HCC in long-term IFN monotherapy.  相似文献   
999.
Meiotic pachytene checkpoints monitor the failure of homologous recombination and synapsis to ensure faithful chromosome segregation during gamete formation. To date, the molecular basis of the mammalian pachytene checkpoints has remained largely unknown. We here report that mouse HORMAD1 is required for a meiotic prophase checkpoint that eliminates asynaptic oocytes. Hormad1-deficient mice are infertile and show an extensive failure of homologous pairing and synapsis, consistent with the evolutionarily conserved function of meiotic HORMA domain proteins. Unexpectedly, Hormad1-deficient ovaries contain a normal number of oocytes despite asynapsis and consequently produce aneuploid oocytes, indicating a checkpoint failure. By the analysis of Hormad1/Spo11 double mutants, the Hormad1 deficiency was found to abrogate the massive oocyte loss in the Spo11-deficient ovary. The Hormad1 deficiency also causes the eventual loss of pseudo sex body in the Spo11-deficient ovary and testis. These results suggest the involvement of HORMAD1 in the repressive chromatin domain formation that is proposed to be important in the meiotic prophase checkpoints. We also show the extensive phosphorylation of HORMAD1 in the Spo11-deficient testis and ovary, suggesting an involvement of novel DNA damage-independent phosphorylation signaling in the surveillance mechanism. Our present results provide clues to HORMAD1-dependent checkpoint in response to asynapsis in mammalian meiosis.  相似文献   
1000.
Pulmonary epithelioid hemangioendothelioma (PEH) is a rare pulmonary neoplasm that was initially described in 1975 as an intravascular bronchioloalveolar tumor. This report presents the case of a patient with multifocal primary pulmonary PEH (11 tumors) in the bilateral lungs. All of the tumors detected in the preoperative computed tomography scan were surgically resected. The patient has been doing well for 9 years after surgery. No tumor recurred for 8 years after surgery until a single recurrent nodule appeared and was thoracoscopically resected.  相似文献   
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