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101.
A Japanese woman presenting with neurologic symptoms was presumptively diagnosed with neurocysticercosis based on imaging findings. Hooklets in the scolex of the resected lesion were not confirmed through histopathological observation. However, the illness was confirmed by mitochondrial DNA analysis to be a solitary neurocysticercosis case caused by the Asian genotype of Taenia solium.  相似文献   
102.
103.
We examined the current status of syphilis-infected pregnant Japanese women, according to the results of syphilis screening and confirmation tests of women who gave birth in Japan between October, 2015 and March, 2016. We requested 2458 obstetrical facilities to provide information of syphilis screening tests and 78.1% of them responded. Considering the response rate and the rate of implementation of confirmation tests, the number of syphilis-infected pregnant Japanese women was estimated to be 250 (1/4022) per year.  相似文献   
104.
Transient thrombocytosis is commonly observed in preterm infants after birth, but its physiological mechanism is still unknown. To understand the mechanism of the transient thrombocytosis in preterm infants we firstly evaluated a correlation between platelet counts and thrombopoietin (TPO) levels in preterm infants and next c-mpl mRNA levels on platelets in healthy preterm infants longitudinally during a half-year of life. The mean platelet counts in 45 very low birth weight infants (mean gestational age 27.4±1.8 weeks, mean birth weight 1047±249 g) was 230±71×109/l just after birth and thereafter gradually increased to 579±178×109/l by 5 weeks of age. The platelet counts continued this level for about next 8 weeks. Serum TPO levels soon after birth and at 1 month of age were significantly higher than those at the age of 2–6 months. There was a significant negative correlation between platelet counts and serum TPO values. The c-mpl expression levels on platelets at birth and at 1 month of age tended to be lower than those on platelets from adults, and the c-mpl levels gradually increased through 6 months of age, although they were still lower than those of adults. Our results suggest that low expression of TPO receptor on platelets until 1 month after birth cause a decreased TPO clearance and keep a high level of free TPO in blood, thereby promoting platelet production from megakaryocytes or their progenitors in bone marrow, resulting in the subsequent thrombocytosis in preterm infants.  相似文献   
105.
106.
We assessed the concordance among seven general pathologists with respect to histologic diagnosis and interpretation of c-kit proto-oncogene (KIT) and platelet-derived growth factor receptor alpha (PDGFRA) immunostaining of 36 cases of primary spindle-cell tumor, predominantly of the gastrointestinal tract, mesentery, and retroperitoneum, based on review of a tissue microarray (TMA) subjected to immunohistochemistry with antibodies to KIT/CD117, PDGFRA, vimentin, desmin, smooth muscle action, CD34, and S-100 protein. Tumors included 20 molecularly analyzed gastrointestinal stromal tumors (GISTs), 4 leiomyosarcomas, 4 schwannomas, 4 desmoid-type fibromatoses, and 4 solitary fibrous tumors. The mean overall concordance with original diagnosis for each histologic type was 91.1%, with a mean kappa value of 0.91. With respect to PDGFRA immunostaining, the four GISTs with PDGFRA mutation were interpreted as cytoplasm positive, but the 16 GISTs with c-kit mutation were interpreted as weak or positive. These results indicate that the overall concordance with original diagnosis in mesenchymal tumors with the use of immunohistochemical panels is high, despite the use of TMAs. To some extent, PDGFRA immunophenotyping may be useful in GISTs with PDGFRA mutation, but it was not highly reproducible or specific. Therefore, in KIT-negative or weakly positive GISTs, mutation analysis will be required.  相似文献   
107.
A unique subset of B cells expressing interleukin‐10 (IL‐10) and transforming growth factor‐β (TGF‐β) plays an essential role in preventing inflammation and autoimmunity. We investigated the presence of this cell subset in intestines and its role in the pathogenesis of ileitis using SAMP1/Yit and age‐matched control AKR/J mice. Mononuclear cells were isolated from mesenteric lymph nodes (MLNs) and the expressions of B220, CD1d, CD5, Toll‐like receptor 4 (TLR4) and TLR9 in isolated cells were analysed. Purified B cells were stimulated with lipopolysaccharide (LPS) or CpG‐DNA, then IL‐10 and TGF‐β1 expressions were examined by enzyme immunoassay and flow cytometry. Production of IL‐1β by TLR‐mediated macrophages co‐cultured with or without purified MLN B cells from SAMP1/Yit and AKR/J mice was evaluated. In addition, interferon‐γ (IFN‐γ) production in intestinal T cells co‐cultured with MLN B cells were also assessed in SAMP1/Yit and AKR/J strains. The production levels of IL‐10 and TGF‐β1 stimulated by LPS and CpG‐DNA were significantly lower in B cells separated from MLNs from the SAMP1/Yit strain. B cells expressing IL‐10 and TGF‐β1 were mainly located in a population characterized by the cell surface marker CD1d+. Interleukin‐1β production by TLR‐activated macrophages co‐cultured with MLN B cells from SAMP1/Yit mice was significantly higher than that of those from AKR/J mice. Interestingly, IFN‐γ production by T cells was noted only when they were co‐cultured with SAMP1/Yit but not the AKR/J B cells. These results are the first to show that disorders of regulatory B‐cell function under innate immune activation may cause disease pathogenesis in a murine model of Crohn’s disease.  相似文献   
108.
Mucopolysaccharidosis IVA (MPS IVA) is an autosomal recessive disorder caused by deficiency of N-acetylgalactosamine-6-sulfate sulfatase (GALNS), required for degradation of keratan sulfate and chondroitin-6-sulfate. In order to study the effects of a missense mutation in the active site cysteine in the GALNS gene that is conserved in all mammalian sulfatases, we produced a p.C76S (an active site replacement) knock-in mouse by replacing the Cys76 with Ser in the endogenous murine Galns by targeted mutagenesis. Homozygous Galns(tm(C76S)slu) mice had no detectable GALNS enzyme activity. At age of 2-4 months, lysosomal storage was present primarily within reticuloendothelial cells such as Kupffer cells and spleen sinusoidal lining cells. Vacuolar change was present in glomerular visceral epithelial cells and was not present in hepatocytes or renal tubular cells. In the brain, hippocampal and neocortical neurons and meningeal cells showed lysosomal storage. Radiographs revealed no change in the skeletal bones of mice up to 12 months old. Thus, the Galns(tm(C76S)slu) mice had visceral storage of GAGs in organs but lacked the skeletal features of human MPS IVA. In contrast to a previously reported transgenic model (Galns(tm(hC79S.mC76S)slu)), in which the inactive human GALNS transgene was overexpressed, no reduction in other sulfatases was observed. In addition, the Galns(tm(C76S)slu) mice displayed milder storage. We conclude that the milder phenotype is characteristic of isolated GALNS deficiency while the more severe phenotype reflected in the Galns(tm(hC79S.mC76S)slu) mice was due to deficiency of other sulfatases caused by oversaturation of the sulfate modifying enzyme by the inactive human gene product.  相似文献   
109.
Autophagy is an evolutionarily conserved process that maintains cellular homeostasis via synthesis, degradation, and subsequent recycling of cellular products under various physiological conditions. However, the link between autophagy and the innate immune system remains unknown. In the present study, we evaluated Toll-like receptor (TLR)-mediated autophagy induction in intestinal epithelial cells (IECs) and its relationship to interleukin (IL)-8 production. IEC-6, HCT-15, RAW264.7, and THP-1 cells were cultured with or without various TLR ligands, followed by evaluation of the expressions of pro-inflammatory cytokines [IL-8, cytokine-induced neutrophil chemoattractants (CINC)-2β, macrophage inflammatory protein (MIP)-2] by real-time PCR and ELISA. To reveal the status of autophagy in IECs and macrophages, light chain 3 (LC3)-II expression was examined using Western blotting and immunofluorescence with confocal microscopy. Also, to evaluate the influence of TLR ligands on autophagy-mediated innate-immune responses, autophagy-related gene (Atg)7 specific siRNA was transfected into intestinal epithelial cells and IL-8 expression was determined following exposure to various TLR ligands. Cells treated with the TLR ligands produced considerable amounts of pro-inflammatory cytokines (IL-8, CINC-2β, MIP-2). Furthermore, the basal levels of LC3-II were markedly higher in IECs as compared to those in macrophages. Our findings indicated that autophagy induction following TLR ligand stimulation was not significantly evident in IECs as compared to macrophages. In addition, Atg7 gene expression silencingled to down-regulation of TLR-mediated IL-8 expression in IECs, which indicates a potential role of autophagy in generating innate-immune responses. In conclusion, autophagy may be an important intracellular machinery for inducing the innate immune system in IECs.  相似文献   
110.
Cardiac hemangioma is relatively rare, accounting for approximately 1–3% of all primary heart tumors. This benign tumor may be an incidental lesion, but can also cause arrhythmias, pericardial effusion, congestive heart failure or outflow obstruction. We report a rare case with exophytic cardiac hemangioma arising from the right ventricle. Echocardiography showed an approximately 40 mm round protruding mass on the anterior wall of the right ventricle. Cardiovascular magnetic resonance demonstrated isointense and hyperintense signals on T1- and T2-weighted images, respectively. These imaging studies suggested a pericardial cyst. Perioperative findings indicated a globular, exophytic mass, vascular in nature, arising from the right ventricle. The lesion was resected directly, and the space left by defect in the right ventricular wall was covered with a bovine pericardial patch. Cardiac hemangiomas are generally endoluminal tumors, but we must keep in mind that the differential diagnoses include various pericardial lesions by medical images.  相似文献   
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