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51.
AIM: To investigate the role of canonical transient receptor potential channel 1 (TRPC1) in the migration of human bronchial epithelial cells (16HBE) induced by transforming growth factor-β1 (TGF-β1). METHODS: Silencing of TRPC1 gene expression was performed by siRNA. The cell activity and apoptosis were measured by CCK-8 assay and flow cytometry, respectively. The migration and invasion abilities of the 16HBE cells were detected by wound- healing assay and Transwell assay. The protein expression of E-cadherin and vimentin was determined by Western blot. RESULTS: TGF-β1 treatment significantly enhanced the cell migration distance compared with control groups (P < 0.01). The results of CCK-8 assay and flow cytometry indicated that there were no significant difference in proliferation and apoptosis among TRPC1 siRNA group, TGF-β1 group and control group (P > 0.05). The results of wound-healing and Transwell assays showed that migration and invasion abilities in TRPC1 siRNA + TGF-β1 group were markedly suppressed compared with TGF-β1 group (P < 0.01). The protein expression of E-cadherin and vimentin induced by TGF-β1 was inhibited by TRPC1 silencing compared with TGF-β1 group (P < 0.05). CONCLUSION: TRPC1 is involved in the migration of human bronchial epithelial cells induced by TGF-β1 through regulating the protein expression of E-cadherin and vimentin.  相似文献   
52.
以末端带氨基的甲氧基聚乙二醇(mPEG-NH_2)、十四胺、5-氨基-1-戊醇、1,4-丁二醇二丙烯酸酯和1,3-戊二胺为原料,采用一锅法合成了一种两亲共聚物聚乙二醇-聚β-氨基酯(mPEG-PBAE),通过FT-IR、GPC、芘荧光探针对聚合物的结构、相对分子质量和临界胶束浓度(CCMC)进行了表征;以漆酚为药物模型分子,采用透析法制备了漆酚/两亲共聚物胶束,采用TEM和DLS对载药胶束的粒径、Zeta电位、形貌进行了表征,考察了载药胶束的pH响应性、体外释药性和体外抗肿瘤活性。研究结果表明:两亲共聚物mPEG-PBAE已经成功合成,重均相对分子质量为11 445,与设计的理论相对分子质量相差不大,聚合物的CCMC值为18.25 mg/L;制备得到的漆酚/两亲共聚物胶束的包封率为82.29%,载药量为23.21%,外观呈规则球形结构,大小均一,平均粒径为160.1 nm,Zeta电位值为33.6 mV,其在pH值为5.0的缓冲溶液中粒径增大明显高于pH值为6.5和7.4的缓冲溶液,具有明显的pH响应性;当pH值为5.0、6.5和7.4时,72 h内累计释药率分别为98.7%、61.6%和31.5%;载药胶束对HepG2和A549肿瘤细胞的半数抑制浓度(IC50)分别为1.38和0.87 mg/L,体外抗肿瘤活性明显优于游离漆酚。  相似文献   
53.
Objective– Failure of passive transfer in neonatal alpacas is often corrected by IV administration of commercial camelid plasma. The goal of this study was to characterize changes in pulmonary function, gas exchange, and cardiovascular parameters associated with IV plasma transfusion. Design– Prospective clinical study. Setting– A university‐based referral hospital. Animals– Eleven clinically healthy alpaca crias (age: 1–18 days) with failure of passive transfer (IgG<8 g/L [800 mg/dL]). Interventions– Thirty milliliters per kilogram of commercial camelid plasma was administered IV over 90 minutes. Before and after the transfusion, the following cardiopulmonary measurements were obtained: arterial blood gas analysis, pulmonary functional residual capacity (FRC), PCV, total plasma protein and echocardiographic M‐mode measures. Additionally, central venous pressure and indirect arterial blood pressure were monitored throughout the plasma transfusion. Measurements and Main Results– The IV plasma transfusion resulted in significantly reduced PCV (−5.4±5.1%), increased total plasma protein (+4±4 g/L [0.4±0.4 g/dL]), elevated central venous pressure and changes in left and right ventricular M‐mode indices, consistent with plasma volume expansion. Transfusion was further associated with a significant increase in arterial oxygen pressure (PaO2) (+11.2±15 mm Hg) and decrease in FRC (−5.6±8.3 mL/kg). Conclusions– IV administration of 30 mL/kg camelid plasma to neonatal crias resulted in measurable plasma volume expansion and a concurrent reduction in FRC. Administration of this quantity of plasma appeared to be safe in healthy neonatal crias. However, changes in lung volume associated with plasma administration may create risks for crias with underlying cardiopulmonary or systemic disease.  相似文献   
54.
The aims of this study were to characterise a model of feline allergic airway inflammation and to test through a longitudinal investigation whether five repeated allergen exposures would lead to signs of airway remodelling that would be detectable in vivo. Eight healthy control cats and eight cats sensitised with Ascaris suum allergens were investigated. Barometric whole body plethysmography (BWBP) was used for the assessment of respiratory variables and airway responsiveness (AR). Bronchoalveolar lavage fluid (BALF) was sampled for cytology and determination of F(2)-isoprostane concentration and matrix metalloproteinase type 9 (MMP-9) activity. Thoracic radiography and bronchoscopy scores were also established. Cats were investigated prior to sensitisation and after inhalation of placebo or allergen challenge 1. BWBP measurements revealed a significant increase of enhanced pause (Penh), an index of bronchoconstriction, and AR in sensitised cats in response to allergen challenge 1. A significant increase in BALF neutrophil and eosinophil %, F(2)-isoprostane concentration and MMP-9 activity, and increased radiography and bronchoscopy scores were recorded. After a recovery period of 6 weeks, all variables except BALF MMP-9 returned to baseline values. Four further allergen challenges induced similar changes to those seen in challenge 1 and no signs of persistent changes suggestive of bronchial remodelling were detectable. The model provides an in vivo approach to functional, inflammatory and morphological changes occurring in response to single and repeated allergen exposure.  相似文献   
55.
Anther-culture response in Lolium perenne was studied in the hybrid populations from three responsive diploid parent clones to obtain genotypes with superior anther-culture response through hybridization. Genetic variation for anther-culture response was significant both within and between the four hybrid families and their parents. A reciprocal effect was indicated for embryo formation and regeneration percentages for one of the cross combinations. Among 55 hybrid clones tested in two environments, 6 clones were identified with an anther-culture response level superior to their parents. While the parents produced one green plant or less per 100 anthers, these superior clones produced from 11 to 59 green plants/100 anthers, mainly as the result of improved embryo formation and improved percentages of regenerated plants being green. A significant correlation (r = 0.397**) was observed between embryo formation and percentage of green plants. The results are discussed with regard to the possible transfer of anther-culture response to non-responsive breeding material through hybridization.  相似文献   
56.
【目的】为提高亚硒酸钠的生物利用率,通过内源乳化法制备环境响应性亚硒酸钠 / 海藻酸钠微 胶囊(SSSAMC)。【方法】以天然高分子海藻酸钠(SA)为壁材、亚硒酸钠(Na2SeO3)为芯材、纳米碳酸钙 (Nano-CaCO3)为交联剂制备 SSSAMC。采用热重分析和扫描电镜与能谱扫描结合分析 SSSAMC 的热稳定性与 形貌。通过测定 SSSAMC 在不同 pH、温度以及离子浓度下的溶胀率,考察 SSSAMC 的环境响应性,并分析了 SSSAMC 溶胀率随时间变化的关系。【结果】该法制备的 SSSAMC 具有良好的热稳定性,兼具 pH、温度和离 子浓度响应性,其响应溶胀过程符合 Schott 溶胀模型,拟合相关系数 R2 在 0.99 以上。【结论】SSSAMC 兼具 良好的热稳定性和环境响应特性,具备作为肠道释放的饲用硒营养剂的应用潜力。  相似文献   
57.
A young Golden Retriever dog developed severe respiratory distress following an initial clinical diagnosis of infectious tracheobronchitis. Severe expiratory flow limitation, associated with exertional respiratory distress and hypoxemia was present. Thoracic images obtained with conventional radiography were characterized by hyperinflation and abnormal bronchial and alveolar patterns. Computed tomography was performed and in conjunction with pulmonary functional changes was diagnostic of small airway disease. The dog was treated with a variety of antibiotics, anti-inflammatory agents, and antitussives, but the clinical signs worsened and the puppy was euthanized. Pathologic examination confirmed severe small airway disease, with emphysema and bronchiolitis.  相似文献   
58.
目的 观察补肺益肾膏方对支气管哮喘非急性发作期的临床疗效,为该膏方的临床应用提供依据。方法 将80例支气管哮喘患者随机分为治疗组和对照组各40例,治疗组服用补肺益肾膏方治疗,对照组不采用膏方干预疗法,两组在观察期间均可在必要时使用舒利迭(沙美特罗替卡松粉吸入剂)治疗以缓解症状,随访1年。结果 治疗组治疗后在中医证候积分、1年内哮喘发作次数和单次住院天数等方面均优于对照组,差异有统计学意义(P<0.05);圣乔治(SGRQ)呼吸问卷评分的疾病影响项与对照组比较,差异有统计学意义(P<0.05)。结论 补肺益肾膏方能有效缓解支气管哮喘的临床症状,减少发作次数,提高患者的生活质量,是防治哮喘的有效途径。  相似文献   
59.
Tracheobronchomalacia has been diagnosed using radiography or bronchoscopy to confirm bronchial changes in luminal diameter during the respiratory cycle. However, studies in healthy humans suggest that some degree of bronchial collapse may be observed during the normal respiratory cycle. In this analytical study, the luminal diameter of the bronchus to each of the six pulmonary lobes and the mean percentage of expiratory collapse from end inspiratory, end expiratory, and two forced expiratory phases (10 and 15 ml/kg) were determined via computed tomography (CT) and radiography in 22 healthy Beagle dogs. The bronchial collapsibility was significantly greater during the forced expiration than the end expiration (< 0.001); the same results were observed in dorsal and sagittal CT images and radiographs (P < 0.001). Median collapsibility values associated with 15 ml/kg forced expiratory collapse determined via cross‐sectional CT images were measured as 16.6–45.5% and differed according to the pulmonary lobe. Median collapsibilities on radiography with 15 ml/kg forced expiration were 57.8% and 62.1% in the right cranial lobe and right caudal lobe, respectively. In conclusion, bronchial diameter may change during the respiratory cycle, and some degree of reduction in bronchial diameter may be an incidental finding in healthy dogs. More rigorous criteria are needed with regards to bronchial collapsibility during normal respiration for the diagnosis of bronchomalacia in order to avoid false‐positive diagnoses.  相似文献   
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