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991.
Narayanan K Krishnamoorthy B Ezhilarasan R Miyamoto S Balakrishnan A 《Cell biology international》2003,27(4):375-382
Tropical pulmonary eosinophilia (TPE) is an occult manifestation of filariasis, brought about by helminth parasites Wuchereria bancrofti and Brugia malayi. Treatment of patients suffering from TPE involves the administration of diethyl carbamazine and Ivermectin. Although the drugs are able to block acute inflammation, they are not able to alleviate chronic basal inflammation. We have attempted to examine the disease by targeting two important components; namely filarial parasitic sheath proteins (FPP) induced apoptosis and pro-inflammatory cytokine response in human laryngeal carcinoma cells of epithelial origin (HEp-2) cells an epithelial cell line. Earlier studies by us have shown that FPP exposure induced apoptosis in these cells. In this study with hydrocortisone, calpain inhibitor (ALLN) and phorbol myristate acetate (PMA) treatments we demonstrate that apoptosis is inhibited as shown by [3H] thymidine incorporation studies, propidium iodide staining and Annexin V staining. Hydrocortisone at a dose, which inhibits cell death also down regulated, the expression of pro-inflammatory cytokines IL-6 and IL-8. These findings give us insights into the multifaceted approach one may adopt to target critical signalling molecules using appropriate inhibitors, which could eventually be used to reduce lung damage in TPE. 相似文献
992.
993.
Ebina T Ogama N Shimanuki H Kubota T Isono N 《Cancer immunology, immunotherapy : CII》2003,52(9):555-560
We devised an innovative type of immunocell therapy called BRM (biological response modifier)-activated killer (BAK) therapy, which utilizes most of non-MHC (major histocompatibility complex) restricted lymphocytes, CD56+ cells including T cells and NK cells. Peripheral blood lymphocytes were selected by immobilizing them with anti-CD3 monoclonal antibody, cultured for 2 weeks with serum-free medium containing IL-2, and then were reactivated by 1,000 U/ml of IFN- for 15 min. The patients were infused with about 6×109 BAK cells by intravenous drip infusion at 1-month intervals. All advanced solid cancer patients who had received chemotherapy but for whom it was not effective or have refused chemotherapy were included in the present study. A good marker of impairment of host immune response by chemotherapy is an immunosuppressive acidic protein (IAP) level in serum above 580 g/ml; survival rates were compared with the high (>580 g/ml) and the low (580 g/ml) serum IAP groups. We enrolled in this study 23 immunosuppressed patients whose IAP levels in serum were over 580 g/ml, and 42 immunoreactive solid cancer outpatients whose IAP level in serum were under 580 g/ml and whose performance statuses were over 80% on the Karnofsky scale. After giving informed consent, patients were treated with BAK therapy on an outpatient basis at our hospital. The ethical review board of the Miyagi Cancer Center approved this pilot study. Treated with BAK therapy, the mean survival of immunosuppressed patients was 4.6 months. On the other hand, survival for one of immunoreactive advanced postoperative patients (stage IV) and inoperable lung cancer patients (stage IIIb) was 24.7 months. The difference in survival between the 2 groups was significant (P<0.01). This shows that BAK therapy is not indicated for an advanced cancer patient whose serum IAP is over 580 g/ml, perhaps due to extensive chemotherapy. Overall response to BAK therapy was complete response (CR) in 5 cases, partial response (PR) in 1 case, and prolonged no change (NC) in 26 cases, with an effectiveness rate at 76.2% in 42 advanced stage IIIb and IV cancer patients. BAK therapy has a life-prolonging effect without any adverse effects and maintains satisfactory quality of life (QOL) for advanced cancer patients. 相似文献
994.
Russo TA Davidson BA Carlino-MacDonald UB Helinski JD Priore RL Knight PR 《FEMS microbiology letters》2003,226(2):355-361
Gram-negative enteric bacilli are agents of life-threatening pneumonia. The role of the bacterial capsule and O-antigen moiety of lipopolysaccharide in the pathogenesis of Gram-negative pneumonia was assessed. In a rat model of pneumonia the LD(50) of a wild-type extraintestinal pathogenic Escherichia coli strain (CP9) was significantly less than its isogenic derivatives deficient in capsule (CP9.137), O-antigen (CP921) or both capsule and O-antigen (CP923) (P< or =0.003). Studies using complement depleted or neutropenic animals established that both neutrophils and complement are important for the pulmonary clearance of E. coli. Data from these studies also support that capsule and O-antigen serve, at least in part, to counter the complement and neutrophil components of the pulmonary host defense response. Lastly, the contribution of E. coli versus neutrophils in causing lung injury was examined. Findings suggest that E. coli virulence factors and/or non-neutrophil host factors are more important mediators of lung injury than neutrophils. These findings extend our understanding of Gram-negative pneumonia and have treatment implications. 相似文献
995.
996.
997.
《Saudi Journal of Biological Sciences》2022,29(5):3366-3371
Formalin is used for different purposes due to its preservation capability. But continuous exposure to formalin may result various health related issues leading to cancer and death. A new alcohol-based fixative, EMA (ethanol, methanol and acetic acid = 3:1:1) could be a safer option in this regard. To compare the health hazards of formalin and EMA, a total 15 adult male mice were randomly distributed into three groups- exposure groups (formalin and EMA) and control group. The mice were subjected to natural inhalation exposure of the fixatives followed by behavioral depression test (forced swimming test), histopathology and serum biochemical tests. Our results showed that the hazardous effects of formalin were remarkably higher than that of EMA. Formalin exposed group showed severe depression (P < 0.001) in the forced swimming test compared to EMA and control groups. Histopathologically, diffuse lymphocytic infiltrations around the lung alveoli and bronchioles and severe inflammation with accumulation of reactive cells in the cerebral cortex were detected in the formalin exposed group, whereas little or no inflammation with fibrinous exudates in the bronchioles was reported in the EMA group and no inflammatory cells were detected in the cerebral tissues. The serum biochemical analysis of the inflammatory mediators (Interleukin-6 and C-reactive protein) revealed that both significantly (P < 0.001) increased in the formalin exposed group compared to EMA and control groups. These results confer that EMA could be a safer option to reduce health hazards of formalin in the workplace environment. 相似文献
998.
IntroductionAdults with high-risk smoking histories benefit from annual lung cancer screening. It is unclear if there is an association between lung cancer screening and smoking cessation among U.S. adults who receive screening.MethodsWe performed this population-based cross-sectional study using data from the Behavioral Risk Factor Surveillance System (2017–2020). We defined individuals eligible for lung cancer screening as adults 55–80 years old with ≥ 30 pack-year smoking history who were currently smoking or quit within the last 15 years. We assessed the association between lung cancer screening and current smoking status.ResultsBetween 2017 and 2020, 12,382 participants met screening criteria. Current smoking was reported by 5685 (45.9 %) participants, of whom 40.4 % (2298) reported a cessation attempt in the prior year. Lung cancer screening was reported by only 2022 (16.3 %) eligible participants. Lung cancer screening was associated with lower likelihood of currently smoking (odds ratio [OR] 0.705, 95 % CI 0.626–0.793) compared to individuals who did not receive screening. Screening was also associated with higher likelihood of reporting a cessation attempt in the prior year (OR 1.562, 95 % CI 1.345–1.815) compared to individuals who did not receive screening.ConclusionsReceipt of lung cancer screening was associated with lower smoking rates and more frequent cessation attempts among U.S. adults. Better implementation of lung cancer screening programs is critical and may profoundly increase smoking cessation in this population at risk of developing lung cancer. 相似文献
999.
摘要 目的:探讨含NLR家族PYRIN域蛋白3(NLR family pyrin domain containing 3,NLRP3)炎症小体对克雷伯杆菌肺炎小鼠肺脏病理损伤的调节作用。方法:56只C57BL/6小鼠随机平分为两组-模型组与对照组,模型组小鼠通过气管注射肺炎克雷伯杆菌建立克雷伯杆菌肺炎模型,对照组小鼠注射等体积的生理盐水,记录与观察肺脏病理损伤情况。结果:模型组建模第7 d与第14 d的肺泡灌洗液髓过氧化酶(Myeloperoxidase,MPO)活性都高于对照组(P<0.05)。模型组建模第7 d与第14 d的肺脏、脾脏、肝脏系数与肺脏病理评分、NLRP3蛋白相对表达水平都高于对照组(P<0.05)。在模型组中,建模第14 d的NLRP3蛋白相对表达水平与肺脏病理评分、肺脏系数、脾脏系数、肝脏系数、肺泡灌洗液MPO活性都存在正相关性(P<0.05)。结论:克雷伯杆菌肺炎小鼠NLRP3炎症小体呈现高表达状况,可介导小鼠肺脏病理损伤,促进MPO活性增加,加重多脏器损伤。 相似文献
1000.
摘要 目的:观察血清分泌型卷曲相关蛋白1(SFRP1)、分泌型卷曲相关蛋白5(SFRP5)、1-磷酸鞘氨醇(S1P)、T细胞免疫球蛋白域及黏蛋白域蛋白4(TIM4)与成人支气管哮喘急性发作期患者肺功能、气道炎症和治疗后再次急性复发的关系。方法:选择火箭军特色医学中心2016年7月~2020年8月期间收治的120例成人支气管哮喘患者,其中47例缓解期患者纳为缓解组,73例急性发作期患者纳为发作组。对比发作组、缓解组血清S1P、SFRP1、TIM4、SFRP5水平、肺功能[第1秒用力呼气容积(FEV1)、用力肺活量(FVC)、FEV1/FVC]、气道炎症[血清总免疫球蛋白E(IgE)、痰嗜酸粒细胞、呼出气一氧化氮(FeNO)、血嗜酸粒细胞],治疗结束后以门诊复查或电话的形式进行随访1年,根据1年内是否再次急性复发分组,分为复发组和未复发组,对比复发组和未复发组的血清S1P、SFRP1、TIM4、SFRP5水平。结果:发作组的S1P、SFRP1、TIM4高于缓解组,SFRP5低于缓解组(P<0.05)。发作组的FEV1、FVC、FEV1/FVC低于缓解组(P<0.05)。发作组的血清总IgE、嗜酸粒细胞、FeNO、血嗜酸粒细胞高于缓解组(P<0.05)。Pearson相关性分析结果显示,S1P、SFRP1、TIM4与FEV1、FVC、FEV1/FVC呈负相关(P<0.05),而与血清总IgE、嗜酸粒细胞、FeNO、血嗜酸粒细胞均呈正相关(P<0.05)。SFRP5与FEV1、FVC、FEV1/FVC呈正相关(P<0.05),而与血清总IgE、嗜酸粒细胞、FeNO、血嗜酸粒细胞均呈负相关(P<0.05)。复发组的S1P、SFRP1、TIM4高于未复发组,SFRP5低于未复发组(P<0.05)。结论:成人支气管哮喘急性发作期患者S1P、SFRP1、TIM4水平异常升高,SFRP5异常降低,且与肺功能、气道炎症、再次急性复发均有一定关系。 相似文献