A New Measure for Assessing the Public Health Response to a Middle East Respiratory Syndrome Coronavirus Outbreak

Contact monitoring is an essential component of the public health response to a Middle East respiratory syndrome coronavirus outbreak, and is required for an effective quarantine to contain the epidemic. The timeliness of a quarantine is associated with its effectiveness. This paper provides a conceptual framework to describe the process of contact monitoring, and proposes a new measure called the “timely quarantined proportion” as a tool to assess the adequacy of a public health response.     

鲍曼不动杆菌临床分离率与耐药率的分析

目的 了解2005～2009年鲍曼不动杆菌在临床标本中的分离情况及其耐药趋势,为临床感染的预防和治疗提供参考资料.方法 回顾分析2005～2009年间所有标本中鲍曼不动杆菌的分离率,菌株在标本与病区的分布及对15种抗菌药物的耐药率.结果 鲍曼不动杆菌的分离率有逐年升高的趋势,从2005年的0.39增至2009年的1.39;其在呼吸道标本的分离率最高（61.69%）,其次是尿液（11.3%） ;病区分布以重症监护室（ICU）最高（44.48%）;鲍曼不动杆菌对15种抗菌药物的耐药率在2005年仅有五种〉50%,而到2009年仅头孢哌酮/舒巴坦的耐药率〈50%,其他14种耐药率均〉50%;其耐药率均呈递增的趋势,耐药性增幅列前3位的分别是：环丙沙星38.1%～76.3%、妥布霉素29.4%～78.3%、庆大霉素39.2%～80.1%.结论 鲍曼不动杆菌的临床分离率在逐年增加,其对多数抗菌药物有较高的耐药性,且耐药率呈逐年上升趋势,尤其是对亚胺培南耐药率的快速增长,应引起临床抗感染治疗的高度重视.     

Isolation and biological analysis of tumor stem cells from pancreatic adenocarcinoma

AIM： To explore the method of isolation and biological analysis of tumor stem cells from pancreatic adenocarcinoma cell line PANC-1. METHODS： The PANC-1 cells were cultured in Dulbecco modified eagle medium F12 （1：1 volume） （DMEM-F12） supplemented with 20% fetal bovine serum （FBS）. Subpopulation cells with properties of tumor stem cells were isolated from pancreatic adenocarcinoma cell line PANC-1 according to the cell surface markers CD44 and CD24 by flow cytometry. The proliferative capability of these cells in vitro were estimated by 3-[4,5-dimehyl-2-thiazolyl]-2, 5-diphenyl- 2H-tetrazolium bromide （MTT） method. And the tumor growth of different subpopulation cells which were injected into the hypodermisof right and left armpit of nude mice was studied, and expression of CD44 and CD24 of the CD44^＋CD24^＋ cell-formed nodules and PANC-1 cells were detected by avidin-biotin-peroxidase complex （ABC） immunohistochemical staining. RESULTS： The 5.1%-17.5% of sorted PANC-1 cells expressed the cell surface marker CD44, 57.8% -70.1% expressed CD24, only 2.1%-3.5% of cells were CD44^＋ CD24^＋. Compared with CD44-CD24- cells, CD44^＋CD24^＋ cells had a lower growth rate in vitro. Implantation of 104 CD44 CD24 cells in nude mice showed no evidenttumor growth at wk 12. In contrast, large tumors were found in nude mice implanted with 103 CD44^＋CD24^＋ cells at wk 4 （2/8）, a 20-fold increase in tumorigenic potential （P 〈 0.05 or P 〈 0.01）. There was no obvious histological difference between the cells of the CD44^＋CD24^＋ cell-formed nodules and PANC-1 cells. CONCLUSION： CD44 and CD24 may be used as the cell surface markers for isolation of pancreatic cancer stem cells from pancreatic adenocarcinoma cell line PANC-1. Subpopulation cells CD44^＋CD24^＋ have properties of tumor stem cells. Because cancer stem cells are thought to be responsible for tumor initiation and its recurrence after an initial response to chemotherapy, it may be a very promising target for new dr     

Cost-Effective Isolation of a Process Impurity of Pregabalin

Cost-effective isolation methods were developed on preparative HPLC, flash LC, and simulated moving bed (SMB) to prepare the process impurity, 3-(aminomethyl)-5-methylhex-4-enoic acid (4-ene impurity), of pregabalin. By a thorough experimental study on the different isolation techniques available, it was concluded that SMB was the most cost-effective. Hence, it was a continuous chromatography that utilized the advantage of SMB so that a high quantity of the impurity was generated in a short period of time. SMB was equipped with eight reversed-phased columns and was used to separate the process impurity of pregabalin. The effects of flow rate in zone 2 (Q2) and 3 (Q3), as well as switching time, on the operating performance parameters like purity, productivity, and desorbent consumption were studied. Operating conditions leading to more than 90% purity in the raffinate outlet stream were identified, together with those achieving optimal performance. All of these developed methods are novel, cost-effective, and can be applied to the isolation of other process- and stability-related impurities of pregabalin.     

电缆绝缘护套中Cr(Ⅵ)的火焰原子吸收光谱测定法

目的建立电缆绝缘护套中Cr(Ⅵ)含量的火焰原子吸收光谱测定方法。方法采用干法灰化分解电缆绝缘护套样品,在稀硝酸介质中,采用火焰原子吸收光谱法测定Cr(Ⅵ)含量。结果在0.001 9~8.00μg/ml的线性范围内,所得Cr(Ⅵ)的线性方程为A=0.114 3c+0.006 3,r=0.999 6。该方法的检出限为0.000 7μg/ml,定量下限为0.001 9μg/ml,平均回收率为97.8%~102.2%,RSD为3.35%~7.13%。结论该方法快速简便,精密度和准确度均较高,适于对电缆绝缘护套中Cr(Ⅵ)的测定。     

Isolation and characterization of beta 1-adrenergic receptors from adult, rat cardiac myocytes

The beta-receptors were isolated from rat cardiac myocytes and characterized. Isolated myocytes were prepared from adult rat hearts and characterized for viability. Membrane proteins were solubilized from myocytes with 1% Triton X-102. The solubilized membrane proteins were fractionated by DEAE-Sephacel ion exchange column chromatography. Two major protein peaks were obtained. The second protein peak sample was found to contain beta-receptors to which 125I-15-(4'-azido-3'-iodobenzyl)-carazolol (125I-ABC) was specifically bound. This sample was labeled covalently with 125I-ABC by UV irradiation. The radiolabeled sample was applied to a Sepharose CL-6B gel column. Two radiolabeled protein peaks, one with a molecular weight of approximately 570,000 and the other with a molecular weight of approximately 95,000 were found. When the 570,000-dalton complex was subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) under reducing conditions, it was dissociated into a component with a molecular weight of 66,000. The 95,000-dalton complex was dissociated into a 58,000-dalton component upon SDS-PAGE under reducing conditions. An excess amount of isoproterenol and propranolol decreased photolabeling of the beta-receptors with 125I-ABC by 60% and 40%, respectively.     

Linear lesions for treating the recurrence of persistent atrial tachyarrhythmia after cryoballoon ablation of atrial fibrillation

Overall, 133 patients underwent 170 procedures for the treatment of persistent ATa following an index cryoballoon pulmonary vein isolation (n = 715). After all the procedures, > 90% of the patients had a roof line, a mitral isthmus and/or septal line, and a cavotricuspid isthmus line. Ninety-two patients (69.2%) were in sinus rhythm after a median of 36 months since the index cryoballoon PVI. ATa: atrial tachyarrhythmia; cryo: cryoballoon; CTI: cavotricuspid isthmus; LSPV: left superior pulmonary vein; LIPV: left inferior pulmonary vein; PVI: pulmonary vein isolation; RF: radiofrequency; RSPV: right superior pulmonary vein; RIPV: right inferior pulmonary vein.