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Objective. To investigate the characteristics of HLA-B27 that render susceptibility to seronegative spondylarthropathies. Methods. Serologic HLA class I typing of Japanese patients with ankylosing spondylitis (AS), juvenile rheumatoid arthritis (JRA), and healthy controls, was performed. HLA-B39 subtypes were determined by polymerase chain reaction-sequence-specific oligohy-bridization. Results. HLA-B27 was present in 40 of 48 patients with AS (83%), and in only 1 of 210 healthy controls (0.5%). Three of 8 patients (37.5%) who were negative for HLA-B27 were positive for HLA-B39, which was significantly higher compared with the HLA-B27-negative controls (6.2% P = 0.01). Significant association with HLA-B39 was also noted in the JRA patients (16.7%; P < 0.01), especially in those patients with pauciarticular-onset disease (33.3%; P < 0.01). Ten of 13 HLA-B39-positive patients had subtype B*3901 and 3 had B*3902. Conclusion. Because HLA-B27 and HLA-B39 share Glu at position 45 and Cys at position 67, both of which constitute components of the peptide-anchoring B pocket, and because they possess similar peptide-ligand motifs, our results may support either the role of the peptides presented by class I antigens or the importance of Cys at position 67, in the development of spondylarthropathies and pauciarticular-onset JRA.  相似文献   
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During hemodialysis, amino acid loss through the dialysate remained a significant problem and was not clear in some dialyzers; therefore, we investigated amino acid loss with hydrophilic and nonhydrophilic polyester–polymer alloy membranes and polyacrylonitrile membranes. Nine maintenance hemodialysis patients were studied to assess amino acid loss during hemodialysis with the three membranes. Total amino acid losses were 85.7 ± 27.2 mg/L, 83.3 ± 16.1 mg/L, and 72.1 ± 22.5 mg/L with the hydrophilic, nonhydrophilic polyester–polymer alloy, and polyacrylonitrile membranes, respectively. Amino acid losses were greater with the hydrophilic membrane compared with the polyacrylonitrile membrane for ornithine (2.0 ± 0.6 vs. 1.4 ± 0.4 mg/L, P = 0.025), phenylalanine (2.4 ± 0.9 vs. 1.8 ± 0.8 mg/L, P = 0.012), and tryptophan (0.6 ± 0.2 vs. 0.4 ± 0.2 mg/L, P = 0.023). Amino acid losses were greater with the nonhydrophilic membrane than with the polyacrylonitrile membrane for ornithine (2.0 ± 0.4 vs. 1.4 ± 0.4 mg/L, P = 0.017), phenylalanine (2.3 ± 0.5 vs. 1.8 ± 0.8 mg/L, P = 0.018), tryptophan (0.7 ± 0.2 vs. 0.4 ± 0.2 mg/L, P = 0.003), and cystine (3.2 ± 0.7 vs. 2.0 ± 0.7 mg/L, P = 0.005). In conclusion, greater losses of ornithine, phenylalanine, tryptophan, and cystine were observed with polyester–polymer alloy than with polyacrylonitrile membranes during hemodialysis. Constant attention should be paid to the amino acid loss profile to improve nutritional control in hemodialysis patients.  相似文献   
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Histiocytic neoplasms, such as Langerhans cell histiocytosis (LCH) and disseminated juvenile xanthogranuloma (JXG), can involve the liver and sometimes cause liver failure. We aimed to classify non-LCH histiocytic proliferating disorders that do not exhibit typical disseminated JXG histology. We examined four pediatric patients who presented with liver failure and splenomegaly. Two patients with liver cirrhosis without cholestasis underwent liver transplantation (LT). The other two patients presented with giant cell hepatitis causing neonatal/infantile acute liver failure (ALF). The infantile ALF patient also underwent LT. Liver dysfunction developed after LT in all three transplant cases and the grafts exhibited massive sinusoidal infiltration of histiocytes with hemophagocytosis, similar to the native liver. The neonatal ALF patient was treated with an LCH-type chemotherapy regimen, and is alive and well at 18 months. Infiltrating histiocytes were positive for CD68 and CD163, and negative for CD1a, CD207, and S-100 protein. The BRAF V600E mutation was not present. Liver histological findings were not consistent with conventional disseminated JXG or LCH, although the histological findings in other organs overlapped those of well-known histiocytic neoplasms. The histological and immunohistochemical findings of infiltrating histiocytes suggest that these four cases constituted a disseminated JXG-like systemic disease.  相似文献   
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Neuroinflammation is well known to be associated with neurodegenerative diseases. Apoptosis signal-regulating kinase 1 (ASK1) is a mitogen-activated protein kinase kinase kinase that has been implicated in neuroinflammation, but its precise cellular and molecular mechanisms remain unknown. In this study, we generated conditional knockout (CKO) mice that lack ASK1 in T cells, dendritic cells, microglia/macrophages, microglia, or astrocytes, to assess the roles of ASK1 during experimental autoimmune encephalomyelitis (EAE). We found that neuroinflammation was reduced in both the early and later stages of EAE in microglia/macrophage-specific ASK1 knockout mice, whereas only the later-stage neuroinflammation was ameliorated in astrocyte-specific ASK1 knockout mice. ASK1 deficiency in T cells and dendritic cells had no significant effects on EAE severity. Further, we found that ASK1 in microglia/macrophages induces a proinflammatory environment, which subsequently activates astrocytes to exacerbate neuroinflammation. Microglia-specific ASK1 deletion was achieved using a CX3CR1CreER system, and we found that ASK1 signaling in microglia played a major role in generating and maintaining disease. Activated astrocytes produce key inflammatory mediators, including CCL2, that further activated and recruited microglia/macrophages, in an astrocytic ASK1-dependent manner. Astrocyte-specific analysis revealed CCL2 expression was higher in the later stage compared with the early stage, suggesting a greater proinflammatory role of astrocytes in the later stage. Our findings demonstrate cell-type–specific roles of ASK1 and suggest phase-specific ASK1-dependent glial cell interactions in EAE pathophysiology. We propose glial ASK1 as a promising therapeutic target for reducing neuroinflammation.

Apoptosis signal-regulating kinase 1 (ASK1) is a mitogen-activated protein kinase (MAPK) kinase kinase that stimulates the c-Jun N-terminal kinase (JNK) and p38 MAPK pathways, and it mediates diverse biological signals leading to cell death, differentiation, and senescence (1, 2). Deletion of ASK1 in mice suppresses neuronal cell death from injury (3, 4), and recent studies indicate that ASK1 is involved in various neurodegenerative diseases, including amyotrophic lateral sclerosis, Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis (MS) (58). MS is an inflammatory disease of the central nervous system (CNS) characterized by localized areas of demyelination. Experimental autoimmune encephalomyelitis (EAE) is a classic model widely used to explore pathogenic mechanisms of MS, generated by administering a myelin basic protein peptide that induces an autoimmune response directed to myelin (9). During MS/EAE, activated microglia/macrophages are the first cells to respond to inflammatory insults within the CNS. Microglia/macrophages may be polarized into proinflammatory or antiinflammatory states, with each state having a distinct molecular phenotype and effector function, and targeting microglia/macrophages may have therapeutic benefits in MS/EAE treatment (1012). Astrocytes, another subset of glia, are the most abundant cell population within the CNS. Astrocytes are involved in the regulation of synaptic function, plasticity, and maintaining brain homeostasis, and they are thought to contribute to the pathogenesis of MS/EAE by producing proinflammatory cytokine/chemokines such as CCL2 (1316). In recent years, astrocytes have also been shown to polarize into different subtypes: A1 astrocytes are neurotoxic, and blocking the conversion of astrocytes into the A1 phenotype is neuroprotective (17, 18); although, nowadays, the activation state is described to be more diverse than the simple A1/A2 nomenclature (19, 20). Studies of intrinsic and external factors involved in astrocyte activation or polarization may provide information regarding how astrocytic function changes during disease, which may lead to the development of novel therapies.We previously reported that ASK1 deficiency ameliorated the severity of EAE, using conventional ASK1 knockout (ASK1 KO) mice (21). In this study, we selectively deleted ASK1 from five types of cells: T cells, dendritic cells, microglia/macrophages, microglia, and astrocytes, to dissect out the roles of ASK1 in different cell types during neuroinflammation. Our study revealed pathogenic roles of ASK1 signaling in innate immune cells and how they interact with each other in the progression of MS/EAE.  相似文献   
59.

Background

This study aimed to determine the radiologic predictors and clarify the clinical features related to survival in patients with combined pulmonary fibrosis and emphysema (CPFE) and lung cancer.

Methods

We retrospectively reviewed the medical chart data and high-resolution computed tomography (HRCT) findings for 81 consecutive patients with CPFE and 92 primary lung cancers (70 men, 11 women; mean age, 70.9 years). We selected 8 axial HRCT images per patient, and visually determined the normal lung, modified Goddard, and fibrosis scores. Multivariate analysis was performed using the Cox proportional hazards regression model.

Results

The major clinical features were a high smoking index of 54.8 pack-years and idiopathic pulmonary fibrosis (n = 44). The major lung cancer profile was a peripherally located squamous cell carcinoma (n = 40) or adenocarcinoma (n = 31) adjacent to emphysema in the upper/middle lobe (n = 27) or fibrosis in the lower lobe (n = 26). The median total normal lung, modified Goddard, and fibrosis scores were 10, 8, and 8, respectively. TNM Classification of malignant tumors (TNM) stage I, II, III, and IV was noted in 37, 7, 26, and 22 patients, respectively. Acute exacerbation occurred in 20 patients. Multivariate analysis showed that a higher normal lung score and TNM stage were independent radiologic and clinical predictors of poor survival at the time of diagnosis of lung cancer.

Conclusions

A markedly reduced area of normal lung on HRCT was a relevant radiologic predictor of survival.  相似文献   
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