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1.
《Vaccine》2020,38(48):7674-7682
Outer membrane vesicles (OMVs) of Neisseria meningitidis contain important antigens to trigger an immune response against meningococci and have been studied as vaccines compounds. The immune response to a vaccine may be affected by its constitution and route of administration. Therefore, Swiss mice were immunized by different routes with OMVs of N. meningitidis B with dimethyl dioctadecyl ammonium bromide in bilayer fragments (DDA-BF) or aluminum hydroxide (AH) as adjuvants. The adjuvants and different routes were compared regarding the immune responses by ELISA, western blot, delayed type hypersensitivity (DTH) and histopathologic analysis. The antigenic preparation generated humoral and cellular immune responses. In quantitative analyzes, in general, AH was superior to DDA-BF. However, analysis such as IgG avidity index, bactericidal activity and immunoblot, revealed no important differences regarding the adjuvant or route of immunization. Regarding the parameters tested, it was not possible to define a superiority between the adjuvants and routes of immunization proposed by this study.  相似文献   
2.
目的观察噻托溴铵粉吸入剂应用于临床治疗支气管扩张症的效果。方法选取我院治疗的148例支气管扩张症患者,随机分为观察组和对比组,对比组给予常规的支气管扩张症治疗;观察组在进行常规治疗的同时给予噻托溴铵粉吸入剂进行治疗。结果治疗后观察组和对比组的BODE指数和临床症状均有改善,但观察组优于对比组,P0.05,差异具有统计学意义。结论使用噻托溴铵粉吸入剂治疗支气管扩张症疗效显著。  相似文献   
3.
Abstract

Pyridostigmine bromide acts as a reversible cholinesterase inhibitor that is used at relatively high doses in treatment of Myasthenia gravis and in low dose regimens as prophylaxis against nerve agents poisoning during the Gulf War. The manifestation of late nonspecific symptoms commonly called Gulf War illness has led to the discussion about the role of pyridostigmine bromide in the pathogenesis of this illness. In our study, we described plasma absorption profile of pyridostigmine bromide after p.o. administration in rats; subsequently, changes in blood biochemical and oxidative stress markers were measured. Pyridostigmine bromide was applied p.o. at the dose of 5.82?mg/kg b.w. according to the previously published recommendations. The absorption of pyridostigmine was relatively fast; the Cmax in plasma was 110.20?±?15.12?ng/ml at Tmax of 197.12?±?17.14?min. The bioavailability expressed as AUCtotal was 44,348?±?7608?min ng/ml. The prolongation of pyridostigmine in circulation is in agreement with relatively long half-life that was 179.00?±?28.54?min. Several blood biochemical markers were altered, including glucose, creatinine, creatine kinase, alanine aminotransferase, aspartate aminotransferase, interleukin-6, triglycerides, and cholesterol. However, the changes could be considered as mild. Thiobarbituric acid reactive substances and ferric reducing ability of plasma indicate suppression of basal metabolism. The results of blood biochemical and oxidative stress markers imply that long-term use might possibly change the basal metabolism and cause cellular damage with inflammatory changes.  相似文献   
4.
Pancreatic cancer (PC) is one of the common malignant tumors in digestive tract with a high fatality rate. The oncogenic role of lysine-specific demethylase1 (LSD1/KDM1?A) has been well recognized in PC. While, the role of its homolog LSD2 (KDM1B) in regulating PC progression is poorly understood. In this study, we attempted to evaluate the functional role of KDM1B in PC cells. The expression of KDM1B was detected by immunohistochemistry and immunoblotting in PC tissues and cells. Lentivirus-mediated shRNA was applied to silence KDM1B in PANC-1 and SW1990 cells. Cell proliferation was measured by MTT and Celigo assay. Cell apoptosis was determined by both Caspase-Glo®3/7 assay and Flow cytometry. Intracellular signaling molecules were detected using a PathScan intracellular signaling array kit. In this study, we found KDM1B was highly expressed in PC tissues compared to paracancerous tissues. Moreover, elevated expression of KDM1B was detected in PC cell lines (BxPC-3, CFPAC-1, PANC-1 and SW1990) as compared with a normal human pancreatic duct epithelial cell line (HPDE6-C7). Further investigations revealed that KDM1B knockdown significantly inhibited PC cell proliferation. Furthermore, the apoptosis of PANC-1 and SW1990 cells was significantly increased after KDM1B knockdown. Notably, the activations of p-ERK1/2, p-Smad2, p-p53, cleaved PARP, cleaved Caspase-3, cleaved Caspase-7, p-eIF2a and Survivin were promoted by KDM1B knockdown, while IkBa was suppressed. Taken together, our findings provided new insights into the critical and multifaceted roles of KDM1B in the regulation of cell proliferation and apoptosis, and offered a potentially novel target in preventing the progression of PC.  相似文献   
5.
It is important to address the periodontitis-associated bacteria in the residual subgingival plaque after scaling and root planing to successfully treat periodontitis. In this study, we explored the possibility of exploiting the ion pairing/complexation of minocycline, Ca2+, and sulfate/sulfonate-bearing biopolymers to develop an intrapocket delivery system of minocycline as an adjunct to scaling and root planing. Minocycline-calcium-dextran sulfate complex microparticles were synthesized from minocycline, CaCl2, and dextran sulfate. They were characterized using Fourier-transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. An in vitro release study was conducted to evaluate the release kinetics of minocycline from these microparticles. Agar disk diffusion assays and biofilm-grown bacteria assays were used to assess antibacterial capability. High loading efficiency (96.98% ± 0.12%) and high loading content (44.69% ± 0.03%) for minocycline were observed for these complex microparticles. Mino-Ca-DS microparticles achieved sustained release of minocycline for at least 9 days at pH 7.4 and 18 days at pH 6.4 in phosphate-buffered saline, respectively. They also demonstrated potent antimicrobial effects against Streptococcus mutans and Aggregatibacter actinomycetemcomitans in agar disk diffusion and biofilm assays. These results suggested that the ion pairing/complexation of minocycline, Ca2+, and sulfonate/sulfate-bearing biopolymers can be exploited to develop complex microparticles as local delivery systems for periodontitis treatment.  相似文献   
6.
Metabolism, environmental fate, and low concentration food residue studies would be facilitated by the use of radiolabeled test articles that can be readily quantified within complex matrices. However, radiochemical approaches for such studies require high specific activities to allow analytical detection of correspondingly low masses of test article. The synthesis of high specific activity (>50 μCi/μmol) [14C]‐radiolabeled phenylbutazone presents a challenge using existing methodology, mainly due to the low solvent volumes required and vigorous refluxing needed to close the pyrazolidinedione ring. Herein, we report on the significant modification of an existing method that allows the synthesis of low masses of high specific activity (>50 μCi/μmol) [14C]‐phenylbutazone under mild conditions with simple purification and high yield. The closure of the pyrazolidinedione ring of 1,2‐diphenyl‐3,5‐pyrazolidinedione was accomplished as a first step with unlabeled 1,2‐diphenylhydrazine and diethyl malonate in 32% yield under gram‐scale conditions, which avoided the challenges of low solvent use and vigorous refluxing. Low mass of high specific activity n‐[1‐14C]‐butyl bromide was then added via a nucleophilic substitution reaction as a final step. Yields ranged from 65% to 92% during multiple synthetic attempts with unlabeled butyl bromide and were greatly influenced by reaction stoichiometry and the selection of base.  相似文献   
7.
目的 建立用五氟苄基溴(PFB-Br)衍生气相色谱法,电子捕获检测器(ECD)定量测定唾液中氰离子(CN-)的方法。方法 取微量唾液,加入缓冲溶液后用乙腈稀释定容,加入定量的PFB-Br摇匀,沸水浴30.0 min进行衍生反应,冷却后直接进样入气相色谱仪分离,以ECD检测器检测。结果 唾液中CN-的质量浓度在0.25~200.0 mg/L呈线性关系,线性相关系数为0.999 4;以100.0 μl唾液量计算,方法最低检出浓度为0.07 mg/L,最低定量浓度为0.25 mg/L;方法的批间精密度为2.4%~5.3%(n=6),批内精密度为1.1%~3.8%(n=6),加标回收率为100.7%~102.1%。唾液常见的无机离子Cl-、F-和SCN-对测定结果均无干扰。样品可在4 ℃保存至少15 d。结论 该方法适用于唾液中氰离子测定,对氰化物中毒的应急检测有应用价值。  相似文献   
8.
目的观察噻托溴铵粉雾剂联合沙美特罗替卡松粉吸入剂治疗慢性阻塞性肺疾病(COPD)急性加重期伴呼吸衰竭的临床疗效及安全性。方法将76例COPD急性加重期伴呼吸衰竭患者随机分为对照组38例和试验组38例。对照组予以常规治疗配合呼吸机辅助通气治疗;试验组在对照组治疗的基础上,予以沙美特罗替卡松粉吸入剂每次1吸,bid,吸入治疗+噻托溴铵粉雾剂每次18μg,qd,吸入治疗。2组患者均治疗2周。比较2组患者的临床疗效、动脉血气指标、降钙素原和免疫功能,以及药物不良反应的发生情况。结果治疗后,试验组和对照组的总有效率分别为92.11%(35例/38例)和73.68%(28例/38例),差异有统计学意义(P<0.05)。治疗后,试验组和对照组的动脉血氧分压分别为(86.35±7.04)和(77.49±6.85)mm Hg,氧合指数分别为(310.89±29.87)和(281.34±27.53)mm Hg,降钙素原分别为(1.42±0.54)和(1.93±0.61)ng·m L-1,肿瘤坏死因子-α分别为(275.49±48.62)和(310.05±54.73)ng·L-1,白细胞介素-8分别为(312.62±75.64)和(389.75±78.76)pg·m L-1,超敏C-反应蛋白分别为(4.73±2.45)和(8.34±2.53)mg·L-1,差异均有统计学意义(均P<0.05)。2组患者治疗期间均未发生药物不良反应。结论噻托溴铵粉雾剂联合沙美特罗替卡松粉吸入剂治疗COPD急性加重期伴呼吸衰竭的临床疗效确切,其能显著降低患者的降钙素原水平,改善患者的血气指标和免疫功能,且安全性较好。  相似文献   
9.
目的 建立同时测定盐酸洛美沙星滴眼液中5种抑菌剂(羟苯甲酯、羟苯乙酯、硫柳汞、苯扎溴铵和苯扎氯铵)的HPLC方法。方法 采用Extend C18(4.6mm×250mm, 5μm)色谱柱,流动相为1%三乙胺溶液(磷酸调pH值至3.0)-甲醇,梯度洗脱,流速为1.0mL/min,柱温35℃,检测波长为262nm。结果 羟苯甲酯、羟苯乙酯、硫柳汞、苯扎溴铵/苯扎氯铵各峰均分离良好;羟苯甲酯在0.0410~0.8204mg/mL范围内线性关系良好(r=1.0000),平均回收率为100.2%(RSD=0.8%, n=9);羟苯乙酯在0.0400~0.7996mg/mL范围内线性关系良好(r=1.0000),平均回收率为100.3%(RSD=0.7%, n=9);硫柳汞在0.0806~1.6112mg/mL范围内线性关系良好(r=0.9995),平均回收率为100.8%(RSD=0.9%, n=9);苯扎溴铵在0.0204~0.4076mg/mL范围内线性关系良好(r=0.9998),平均回收率为100.0%(RSD=0.9%, n=9);苯扎氯铵0.0197~0.3932mg/mL范围内线性关系良好(r=1.0000),平均回收率为100.4%(RSD=1.0%, n=9)。结论 该方法准确、灵敏、简便,可用于盐酸洛美沙星滴眼液中羟苯甲酯、羟苯乙酯、硫柳汞、苯扎溴铵及苯扎氯铵5种抑菌剂的检查。  相似文献   
10.
蒋燕 《中国抗生素杂志》2018,43(8):1062-1066
吲哚类化合物作为一类具有广泛生物和药理活性的有机分子,其合成研究具有重要的价值。而通过N-芳基烯胺的分子内氧化偶联反应构建吲哚类化合物成为合成吲哚类化合物最直接、高效的方法之一,得到合成化学家的广泛关注。基于此,本文发展以便宜的二价铜盐(CuBr2)、绿色氧化剂(O2)和吡啶作为配体共同促进的N-芳基-β-烯胺酯的分子内氧化环合反应,以58%~94%的收率成功地合成一系列2,3-二取代的吲哚类化合物,并对其进行核磁共振氢谱和碳谱表征。该合成策略为吲哚类化合物的合成提供了新的方法。  相似文献   
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