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51.

Background

IgG4 production is regulated by type 2 (IL-4 and IL-13) and regulatory (IL-10) cytokines involved in the pathophysiology of chronic rhinosinusitis (CRS). We sought to determine the pathophysiological characteristics of IgG4-positive cells in sinonasal tissues in CRS, especially eosinophilic CRS (ECRS).

Methods

IgG4-positive cells in uncinate tissues (UT) and nasal polyps (NP) were examined by immunohistochemistry. Associations between the number of IgG4-positive cells and clinicopathological factors were analyzed. Receiver operating characteristics (ROC) analysis was performed to determine the cut-off value of IgG4-positive cells in tissue that can predict the post-operative course.

Results

IgG4 was mainly expressed in infiltrating plasma and plasmacytoid cells, and the number of IgG4-positive cells was significantly higher in NP, especially those from severe ECRS patients, than in UT. In CRS patients, the number of IgG4-positive cells significantly and positively correlated with blood and tissue eosinophilia, radiological severity, and serum level of total IgE. The number of infiltrating IgG4-positive cells was significantly higher in patients with a poor post-operative course (sustained sinus shadow 6 months after surgery) than in those with a good one. The number of IgG4-positive cells in NP could discriminate patients with a good or a poor post-operative course (area under the curve: 0.769). Also, 73.3% sensitivity and 82.5% specificity were achieved when the cut-off value was set at 17 cells/high-power field.

Conclusions

Our results suggest that the local expression of IgG4 on cells may be used as a biomarker that reflects the pathophysiology of CRS, including the post-operative course.  相似文献   
52.

Background

IL-10 is a major anti-inflammatory cytokine that prevents inflammation-mediated tissue damage. We characterized the production of IL-10 by sinonasal tissue cells following exposure to Staphylococcus aureus enterotoxin B (SEB), which elicits cellular responses and is associated with the pathogenesis of eosinophilic chronic rhinosinusitis (ECRS).

Methods

Dispersed nasal polyp (NP) cells and uncinate tissue (UT) cells were prepared from patients with CRS with and without NP, respectively. Cells were incubated with SEB, and then the levels of IL-10 in the cell supernatants were determined. The effect of neutralizing IL-10 on SEB-induced IL-5, IL-13, IFN-γ, and IL-17A production was examined. Expression of IL-10 in NPs was also determined.

Results

IL-10 was expressed in infiltrating inflammatory cells in NPs. NP cells, especially non-adherent NP cells, produced substantial amounts of IL-10 in response to SEB. Although baseline production of IL-10 was significantly higher in NP cells than UT cells, the degree of IL-10 response to SEB was not significantly different between the cell types. The degree of IL-10 production was negatively correlated with the degree of eosinophilia both in tissues and peripheral blood whereas positively correlated with the 1-s forced expiratory volume/forced vital capacity ratio. Patients with severe ECRS displayed a significant decrease in IL-10 production compared with those with non-ECRS. IL-10 neutralization significantly augmented SEB-induced IL-13 and IFN-γ production by NP cells.

Conclusions

Impaired IL-10 production in response to SEB in NP may exacerbate the pathophysiology of ECRS including eosinophilia and lower airway obstruction.  相似文献   
53.

Objective

Although colorectal cancer (CRC) is one of the most frequent malignancies in Japan, the associated genetic factors remain to be elucidated. Functional loss of the transporter associated with antigen processing (TAP) 1 gene induces carcinogenesis. We investigated whether single nucleotide polymorphisms (SNPs) in the TAP1 gene (rs735883) are associated with susceptibility to CRC in a Japanese population.

Methods

The study participants were 143 cases and 243 clinical controls. After extracting DNA from their peripheral blood cells, genotyping was conducted by the polymerase chain reaction–restriction fragment length polymorphism method.

Results

Participants with a mutated allele had an increased risk for CRC. The adjusted odds ratios for the C/T, T/T, and the mutation type (C/T + T/T) compared to that of wild type (C/C) were 2.27 [95 % confidence interval (CI), 1.43–3.67], 1.95 (95 % CI, 0.88–4.30), and 2.22 (95 % CI, 1.42–3.55), respectively. Furthermore, a significant trend in the rate of cases was observed with an increasing number of mutated alleles (P for trend = 0.0068).

Conclusions

The genotype of the TAP1 gene is associated with susceptibility to CRC.  相似文献   
54.
ObjectiveComputer-aided design and computer-aided manufacturing (CAD/CAM) techniques are increasingly applied to mandibular reconstruction, but the superiority of this method in oral food intake has not been well established. Considering the extent of mandibular defects, this retrospective study was aimed to clarify the impact of CAD/CAM mandibular reconstruction on chewing and swallowing function after surgery for locally advanced oral cancer.Materials and methodsWe performed a retrospective review of 50 patients who had undergone segmental mandibulectomy with free flap reconstruction for locally advanced oral cancer. The patients’ Functional Oral Intake Scale scores were measured at 3 months after surgery, and possible contributing factors including CAD/CAM mandibular reconstruction and the extent of mandibular defects for oral food intake were subjected to univariate analysis and multivariate logistic regression analysis.ResultsMultivariate logistic regression analysis showed that CAD/CAM mandibular reconstruction was independently associated with good oral intake, whereas both anterior or extensive mandibular resection and glossectomy were also independently associated with poor oral intake after surgery.ConclusionThe present study showed the positive impact of CAD/CAM mandibular reconstruction on chewing and swallowing function after surgery for locally advanced oral cancer for the first time.  相似文献   
55.
Signal regulatory protein α (SIRPα) is expressed predominantly on type 2 conventional dendritic cells (cDC2s) and macrophages. We previously showed that mice systemically lacking SIRPα were resistant to experimental autoimmune encephalomyelitis (EAE). Here, we showed that deletion of SIRPα in CD11c+ cells of mice (SirpaΔDC mice) also markedly ameliorated the development of EAE. The frequency of cDCs and migratory DCs (mDCs), as well as that of Th17 cells, were significantly reduced in draining lymph nodes of SirpaΔDC mice at the onset of EAE. In addition, we found the marked reduction in the number of Th17 cells and DCs in the CNS of SirpaΔDC mice at the peak of EAE. Whereas inducible systemic ablation of SIRPα before the induction of EAE prevented disease development, that after EAE onset did not ameliorate the clinical signs of disease. We also found that EAE development was partially attenuated in mice with CD11c+ cell-specific ablation of CD47, a ligand of SIRPα. Collectively, our results suggest that SIRPα expressed on CD11c+ cells, such as cDC2s and mDCs, is indispensable for the development of EAE, being required for the priming of self-reactive Th17 cells in the periphery as well as for the inflammation in the CNS.  相似文献   
56.
57.
Background/Aims: This study aimed to determine the expression level of interferon alpha/beta (IFN-α/β) receptor in the liver immunohistochemically and evaluate its usefulness in predicting the outcome to IFN therapy in patients with chronic hepatitis C.Methods: The level of IFN-α/β receptor expression was determined in immunoperoxidase-stained pretreatment sections of 55 chronic hepatitis C patients later treated with IFN. We used liver biopsy specimens and mouse monoclonal anti-human IFN-α/β receptor antibody. Quantitative analysis of immunostaining was performed by image analysis software. The level of IFN-α/β receptor was expressed as Unit (U). Sustained responders were patients who showed persistent disappearance of serum HCV-RNA during the 6-month period after treatment, while non-responders showed persistence of viremia after therapy.Results: Positive immunostaining was observed in the cytoplasm of hepatocytes. The mean expression level of hepatic IFN-α/β receptor in sustained responders (2.65±1.11 U, n=15) was significantly (p<0.001) higher than in non-responders (1.61±1.05 U, n=40). A significant decrease in IFN-α/β receptor expression level was observed in patients with advanced liver fibrosis. In patients with low level viremia (pretreatment serum HCV-RNA <1 Meq/ml, n=18), the level of IFN-α/β receptor in sustained responders (2.89±1.12 U, n=11) was significantly (p<0.01) higher than in non-responders (0.93±0.33 U, n=7).Conclusions: Our results suggest that measurement of the level of hepatic IFN-α/β receptor in patients with chronic hepatitis C might be useful for predicting the response to IFN therapy. Resistance to IFN therapy in patients with chronic hepatitis C might be due to low levels of hepatic IFN-α/β receptor.  相似文献   
58.
Background The efficacy of sirolimus-eluting stents (SESs) has not been established in dialysis patients. Methods and Results This study was a non-randomized observational single-center registry in a community hospital: data for 80 consecutive dialysis patients who underwent percutaneous coronary intervention (PCI) with SES were compared with those of a historical group of consecutive 124 dialysis patients treated with bare-metal stents (BMS). After 1 year, the cumulative incidence of major adverse cardiac events (MACE), comprising cardiac death, nonfatal myocardial infarction, stent thrombosis, or target lesion revascularization (TLR), was 25.2% in the SES group and 38.2% in the BMS group (p=0.048). In multivariate analysis, use of SES remained an independent predictor of MACE at 1 year after PCI (risk ratio 0.70, 95% confidence interval 0.52-0.93, p=0.015). Rates of TLR were 21.7% in the SES group and 30.9% in the BMS group and (p=0.15). Subgroup analysis showed that use of SES was effective in patients with small vessels, non-diabetic patients, and patients without highly calcified lesions. Conclusions In dialysis patients, the implantation of SES was moderately effective in reducing MACE at 1 year after PCI as compared with BMS. However, the TLR rate at 1 year was relatively higher than previously reported. (Circ J 2008; 72: 1430 - 1435).  相似文献   
59.
Rotational atherectomy is an indispensable modality for percutaneous coronary intervention of severely calcified lesions. An entrapped rotablator burr is a rare but life‐threatening complication because retrieval is difficult. Although emergent surgical removal is a reliable option for this complication, it is invasive. There are various methods to retrieve an entrapped burr by bailout endovascular approaches. We present two cases of successful rescue of stuck rotablator burr entrapment using a Kiwami straight catheter (4 Fr, Heartrail II, Terumo, Tokyo, Japan). © 2015 Wiley Periodicals, Inc.  相似文献   
60.
Neoadjuvant chemotherapy (NAC) is a standard regimen in treatment of breast cancer patients, but some are resistant to NAC. We hypothesized that breast cancer cells overexpressing epithelial cell adhesion molecule (EpCAM) could be resistant to NAC, contributing to a poor prognosis. Seventy patients with breast cancer were treated with NAC. Core needle biopsy (CNB) specimens and resected tumors before and after NAC, respectively, were examined for expression of EpCAM. In resected tumors, high EpCAM expression correlated with lymphovascular invasion status and nuclear grade (P = 0.01 and 0.008, respectively), and was associated with poor pathological and clinical responses (P < 0.001). High tumoral EpCAM expression in resected tumor was independently related to a poor pathological response. Patients with high EpCAM expression before and after NAC (high‐to‐high group) showed worse pathological and clinical responses (P = 0.008 and <0.001, respectively) than the patients with high and low EpCAM expression before and after NAC, respectively (high‐to‐low group). The overall survival rate of the high‐to‐high group appeared shorter compared with the high‐to low‐group (P = 0.049). Our findings imply that higher levels of EpCAM in breast cancer may be associated with poor response to NAC via a potential chemoresistant effect.  相似文献   
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