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11.
Purpose: Hazelnut and birch pollen are known to destroy tear film components and attack ocular surface cells. We investigated further pollen species from different plant families, whether they show similar effects on human tear fluid and an epithelial cell line in vitro, to provide a broad basis for further research on pollen reactions affecting the tear film and ocular surface.

Materials and methods: Regional pollen species from different plant families (Adoxaceae, Betulaceae, Fagaceae, Juglandaceae, Malvaceae, Oleaceae, Pinaceae, Plantaginaceae, Poaceae, Salicaceae, Sapindaceae) were collected. Their proteolytic activity was evaluated by Zymography. Human tear fluid and cells of an epithelial cell line were incubated with pollen extracts. Tear fluid was analyzed by Polyacrylamide gel electrophoresis (PAGE). Cytomorphology was assessed microscopically and cell viability by proliferation (MTS), water-soluble tetrazolium (WST-1) assay and the impedance-based xCELLigence real-time analysis (RTCA).

Results: Zymography revealed significant protease activity and PAGE showed the degradation of tear proteins by different pollen species. Cells incubated with pollen extracts presented dose- and time-dependent cytomorphological changes. MTS, WST-1, and RTCA revealed cytostatic as well as cytotoxic effects of pollen extracts.

Conclusions: Pollen species from different plant families exert proteolytic activity and degrade human tear fluid as well as epithelial cells, which may play a crucial role in the pathogenesis of allergic and non-allergic reactions affecting the ocular surface.  相似文献   

12.
In order to evaluate the in vivo effect of inhaled formulations, it is a gold standard to create a lung metastasis model by intravenously injecting cancer cells into an animal. Because the cancer grows from the blood vessel side, there is a possibility of underestimating the effect of an inhaled formulation administered to the lung epithelium side. In addition, the metastasis model has disadvantages in terms of preparation time and expense. The present study aimed to establish a new method to evaluate the effect of an inhaled small interfering RNA (siRNA) formulation that is more correct, more rapid, and less expensive. We investigated whether siRNA can suppress gene expression of plasmid DNA (pDNA) by serial pulmonary administration of siRNA and pDNA powders prepared by spray-freeze-drying. We revealed that formulations of dry siRNA powder significantly suppressed gene expression of pDNA powder compared with a control group with no siRNA. Naked siRNA inhalation powder with no vector showed the suppression of gene expression equivalent to that of an siRNA-polyethyleneimine complex without damaging tissues. These results show that the present method is suitable for evaluating the gene-silencing effect of inhaled siRNA powders.  相似文献   
13.
关节假体周围感染(periprosthetic joint infection,PJI)是人工关节置换术后可能发生的一种严重并发症,其导致的严重后果,无论对于医生还是患者来说,都很难接受。目前,由于多种不确定因素的存在,PJI诊断的准确性较低。传统的血清学检查、影像学检查有一定的价值,但是易受全身情况的影响,导致特异性不高。为了正确诊断关节假体周围感染,不同学科的研究人员采用各种不同的方法进行了大量的诊断研究,并取得了丰富的成果。近年来,关节滑液炎性标志物检测、分子生物学方法等被研究证实具有较高的敏感性和特异性。因此,关节滑液CRP、-防御素、白细胞酯酶、PCR技术等被广泛研究,期望能从中找到诊断关节假体周围感染的特异性指标,提高临床诊断的准确性。  相似文献   
14.
BackgroundClinical tests of foot posture and mobility are not strongly related to the dynamic kinematics of the foot during gait. These measures may be more directly related to foot and ankle kinetics. The supination resistance test (SRT) is a clinical test that may more directly measure forces acting on the weightbearing foot to provide clinicians with insight about the loading of foot structures.Research QuestionWhat is the relationship between the SRT in relaxed calcaneal stance and in single-leg-stance and the kinetics and kinematics of the foot and ankle during gait?Methods10 healthy adults between the ages of 18 and 65 were recruited to participate in this study. Three-dimensional motion analysis was performed using the Oxford Foot Model during gait. The results of the SRT were compared with peak midfoot and ankle joint moments, power generation and absorption, joint angles, and peak angular velocities and accelerations. Correlation coefficients were calculated to assess the strength of relationships between these variables and the SRT.ResultsThe SRT demonstrated significant relationships with several variables. In relaxed calcaneal stance, the SRT was inversely related to maximum midfoot pronation moments (r = −0.51), maximum midfoot plantarflexion moments (rho = −0.71), and peak midfoot power generation (r = −0.61). In single-leg-stance, the SRT was significantly related to maximum midfoot plantarflexion moments (rho = −0.55) and peak midfoot power generation (r = −0.47).SignificanceThe SRT is significantly associated to several kinetic variables that quantify midfoot loading during gait. Interventions that decrease supination resistance may have the potential to increase midfoot power generation.  相似文献   
15.
小青龙汤出自《伤寒杂病论》,是疗效确切、使用广泛的经典方剂,一直以来被归为辛温解表剂范畴。本文通过梳理历代的医籍论述,结合古代医案、现代研究、临床应用情况,探讨小青龙汤证的因机证治与方药特点。认为"饮"邪往往是小青龙汤证的病机关键,且治"饮"是小青龙汤组方用药的核心意图所在。若囿于"外寒内饮"之说,恐不能充分发挥其应有的疗效。  相似文献   
16.
目的观察限制液体复苏在创伤失血性休克患者急救中的应用效果。方法选取福建医科大学附属南平市第一医院收治的76例创伤失血性休克患者作为研究对象,依据入院前后顺序将其分为对照组(n=38)和观察组(n=38),对照组接受积极液体复苏方案,观察组接受限制液体复苏方案,比较两组治愈率、治疗后各指标水平、液体输入量及并发症发生情况。结果观察组治愈率明显高于对照组,液体输入量明显低于对照组,差异有统计学意义(P<0.05);治疗后观察组乳酸、凝血酶原时间、平均动脉压及血红蛋白水平均明显优于对照组,差异均有统计学意义(P<0.05);观察组并发症发生率为15.8%,明显低于对照组的36.8%,差异有统计学意义(P<0.05)。结论限制液体复苏应用在创伤失血性休克患者急救中,可提高患者的治愈率,改善乳酸、凝血酶原时间等指标水平,降低并发症发生率的效果优于积极液体复苏应用效果。  相似文献   
17.
Understanding the physiology of fluid distribution in the human body is fundamental to good clinical practice in anaesthesia and intensive care. Intravenous fluid therapies have a range of clinical and metabolic consequences, and they should be context and patient specific. Inadequate or excessive fluid treatment is harmful to patients. There are numerous trials, both historical and current, investigating best practice in fluid therapy. New paradigms and guidelines are being published, and it is important for clinicians to keep up to date with current practice. There is also a continued drive to improve the safety of donor blood products and prevent transfusion errors. Knowledge of how blood products are collected, separated, stored and administered is essential to prevent harm to patients through transfusions. The development of blood substitutes is progressing, and multinational trials are ongoing.  相似文献   
18.
19.
Macrophages are the most abundant immune cells in the lung, which play an important role in COPD. The anti-inflammatory and anti-oxidation of ergosterol are well documented. However, the effect of ergosterol on macrophage polarization has not been studied. The objective of this work was to investigate the effect of ergosterol on macrophage polarization in CSE-induced RAW264.7 cells and Sprague-Dawley (SD) rats COPD model. Our results demonstrate that CSE-induced macrophages tend to the M1 polarization via increasing ROS, IL-6 and TNF-α, as well as increasing MMP-9 to destroy the lung construction in both RAW264.7 cells and SD rats. However, treatment of RAW264.7 cells and SD rats with ergosterol inhibited CSE-induced inflammatory by decreasing ROS, IL-6 and TNF-α, and increasing IL-10 and TGF-β, shuffling the dynamic polarization of macrophages from M1 to M2 both in vitro and in vivo. Ergosterol also decreased the expression of M1 marker CD40, while increased that of M2 marker CD163. Moreover, ergosterol improved the lung characters in rats by decreasing MMP-9. Furthermore, ergosterol elevated HDAC3 activation and suppressed P300/CBP and PCAF activation as well as acetyl NF-κB/p65 and IKKβ, demonstrating that HDAC3 deacetylation was involved in the effect of ergosterol on macrophage polarization. These results also provide a proof in immunoregulation of ergosterol for therapeutic effects of cultured C. sinensis on COPD patients.  相似文献   
20.
徐慧  陈敏  孙永峰  程星  王琦  靳蓉 《广东医学》2020,41(23):2394-2397
目的分析贵阳地区儿童重症社区获得性肺炎支气管肺泡灌洗液(BALF)病原学分布及耐药特点。方法收集989例重症社区获得性肺炎患儿临床资料,将支气管肺泡灌液采用支气管镜取出进行细菌培养、病毒以及肺炎支原体(MP)检测。结果(1)989例重症社区获得性肺炎患儿病原检出阳性716例,阳性率72.40%,细菌、病毒、支原体检出率分别33.27% (329例)、22.45%(222例)、31.45%(311例)。(2)细菌感染中的肺炎链球菌、金黄色葡萄球菌为最为常见的革兰阳性菌株(G+);而肺炎克雷伯菌、大肠埃希菌为最为常见的革兰阴性菌株(G-)。培养菌株对青霉素类、红霉素、第1、2、3代头孢类抗生素有较高的耐药性,对头孢吡肟、拉氧头孢、哌拉西林、左氧氟沙星有较高的敏感性,对亚胺培南、万古霉素、利奈唑烷均无耐药发生。(3)病毒感染检出222例,其中呼吸道合胞病毒131例,腺病毒检测49例,流感病毒6例(A型2例,B型4例),副流感病毒36例(1型3例、2型4例、3型29例),病毒检出率以0~12月龄组最高,RSV、ADV感染主要集中在冬春季节。(4)肺炎支原体检出阳性率31.45%(311例),肺炎支原体检出率以3~5岁组最高。结论贵阳地区重症肺炎中肺炎克雷伯杆菌、肺炎链球菌、大肠埃希菌、金黄色葡萄球菌为重要的细菌病原。重要病毒为腺病毒和呼吸道病毒为主,1~12月龄组的病毒感染检出率比较高。  相似文献   
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