超声处理对羊瘙痒病脑组织中PrPSc聚集状态的影响

目的 研究超声处理对感染羊瘙痒症仓鼠脑组织中PrP^Sc聚集状态的影响，寻找产生PrP^Sc低聚体的条件。方法 裂解液制备脑组织提取物，用各种超声条件处理不同阶段的脑组织提取物；以蛋白酶消化后的Western blot方法和图象分析系统观测PrP^Sc蛋白的分布和聚集状态。结果 适当的超声处理(15s共30次)可增加脑组织匀浆上清中PrP^Sc含量1．29～1．58倍；同样条件下超声处理可明显增加羊瘙痒因子263K感染仓鼠脑组织匀浆上清中PrP蛋白总量，而对正常对照仓鼠脑组织匀浆上清中PrP蛋白总量影响不大；对经常规高速离心获得的PrP^Sc的超声处理显示约90％的PrP^Sc存在于离心上清液中。结论 对感染动物脑组织进行超声处理可增加PrP^Sc的提取量，利于实验室检测。适当的超声处理可破碎大的相对分子质量的PrP^Sc聚集物，产生小的相对分子质量的PrP^Sc产物。     

心脏靶向超声造影剂空气白蛋白微球的研究(1)

按正交设计筛选了用发射超声能量合成白蛋白空气微球的较佳制备工艺,并对微球的形态、粒径与粒径分布、稳定性、安全性和显影效果进行了系统研究。结果表明：微球的平均直径为 ４．２±０． ２ μｍ,平均浓度为（３．５±１．２）×１０８／ｍｌ。９２．５％的微球直径小于１０μｍ,微球在２℃～５℃条件下能稳定储存１２个月,经兔外用静脉注射后能顺利通过肺微循环到达左心室致使左心室靶向超声显影。     

肝脏实时剪切波弹性成像和超声量化评分评价恩替卡韦治疗慢性乙型肝炎肝纤维化疗效的研究

目的 评价恩替卡韦治疗慢性乙型肝炎肝纤维化的疗效,并使用肝脏实时剪切波弹性成像和超声量化评分对疗效进行对比分析.方法 选择在2017年10月至2018年3月本院收治的54例慢性乙型肝炎肝纤维化患者,对其进行肝脏实时剪切波弹性成像和超声量化检查,之后对患者实施恩替卡韦治疗,治疗周期为1年,治疗后再次实施肝脏实时剪切波弹性...     

诊断超声对大鼠子宫组织细胞凋亡状况的影响

目的　检测诊断超声对大鼠子宫组织细胞凋亡状况的影响 ,探讨诊断超声的安全性。方法健康SD雌性大鼠 42只 ,鼠龄为出生后 80～ 85d ,体重 (2 3 0± 5 )g ,随机分为 7组。应用诊断超声对SD大鼠子宫持续辐照 3 0min ,按输出功率及辐照后时间不同分组 ,对照组为空照组。进行常规石蜡包埋切片 ,TUNEL技术检测上述各组凋亡细胞 ,光学显微镜进行形态学观察 ,透射电子显微镜观察超微结构。结果　超声辐照后 12h细胞凋亡率增加 ,2 4h增加最多 ,48h细胞凋亡率下降 ,96h细胞凋亡率继续下降 ,12 0h恢复至对照组水平。光学显微镜和透射电子显微镜观察到细胞凋亡的形态学改变 :染色质致密 ,固缩聚集于细胞核核膜 ,呈境界分明的块状或新月形小体 ,细胞核裂解和凋亡小体形成。结论　诊断超声辐照大鼠子宫可诱导细胞凋亡增加 ,但存在一定的可复性 ,且细胞凋亡率与超声输出功率呈正相关     

实现非侵入式超声塑形的关键技术

非侵入式超声塑形是最近几年刚刚兴起的新技术，具有安全元创的优点。本文简要讨论超声塑形的物理机理、工作参数、实际系统构成和工作原理，重点介绍了其中的两项关键技术即发射换能器和频率跟踪技术的应用。     

超声介导载基因微泡靶向传输血管内皮生长因子促心肌血管新生

目的　探讨超声介导载血管内皮生长因子 16 5 (VEGF165)基因靶向微泡促梗死心肌血管新生的可行性。方法　构建真核表达质粒 pcDNA3 1-/VEGFcDNA165,将其包载于脂质泡中 ,超声辐射下向鼠心肌传输。采用RT PCR、WesternBlot检测mRNA、蛋白表达 ,观察微血管密度评价血管新生效果。结果　 (1)成功构建VEGF165基因 ;(2 )脂质体微泡可包载VEGF165基因 ;(3)超声介导辐射下向心肌靶向传输VEGF165基因 ,实验组基因表达及血管密度高于空白对照组 ,但低于VEGF165基因心肌直接注射。结论　具有心肌显影功能的脂质体载VEGF165基因微泡在超声辐射下可向大鼠梗死心肌靶向传输 ,并产生促血管新生效应。     

How should microbiology laboratories interpret cultures of the sonicate of closed needleless connectors?

IntroductionOur objective was to determine whether there is a cut-off in the needleless connectors’ (NCs) cultures that when combined with skin cultures it was as efficient as conventional superficial cultures to rule-out catheter colonization (CC) and catheter-related bloodstream infection (CRBSI).MethodsDuring 10 months, we collected samples and then we analyzed the validity values of skin + NCs cultures for CC and CRBSI considering the best cut-off showing at least >90% of specificity to have a high negative predictive value using a ROC curve.ResultsWe collected a total of 167 catheters. The optimal cut-off of NCs culture was 1000 cfu/NC. The validity values for CC and CRBSI combining skin cultures and NCs cultures using the selected cut-off were, respectively: S, 42.9%/16.7%; SP, 83.6%/75.8%; PPV, 27.3%/2.5%; and NPV, 91.0%/96.0%.ConclusionsThe combination of skin cultures and quantitative NCs cultures could be used for ruling-out CC and CRBSI.     

The utility of dithiothreitol treatment of periprosthetic tissues and explanted implants in the diagnosis of prosthetic joint infection

PurposeThe methods used for the processing of periprosthetic tissues and explanted implants to improve culture outcome especially in biofilm mediated prosthetic joint infections (PJIs) are still debated upon. Studies have reported that Dithiothreitol (DTT) pretreatment of infected devices gives similar results as sonication. However, none of them evaluated the DTT treatment of periprosthetic tissues and explanted implants in the same cohort. We evaluated the diagnostic utility of DTT treatment of periprosthetic tissue and explanted implants, as compared to the normal saline treatment of periprosthetic tissues and sonication of explanted implants for the diagnosis of PJI.MethodsSeventy-three revision arthroplasty cases were prospectively included in this study. Three to five tissue specimens and the explanted implants were collected from each patient. Periprosthetic tissue samples were processed by both normal saline and DTT treatments. Explanted implants were subjected to both DTT treatment and sonication. Musculoskeletal Infection Society (MSIS) PJI criteria was used as the reference standard for the diagnosis of PJI.ResultsOf the 73 cases enrolled, 34 had PJI and 39 were aseptic failures. The sensitivity of DTT treated periprosthetic tissue culture (PTC) and saline treated PTC was similar (66.6% vs 58.8%, P = 0.25). The specificity of both was 100%. Sonication and DTT treatment of explanted implants showed comparable sensitivity (85.3% vs 82.4%) and specificity (100% vs 97.4%), P > 0.99. Compared to DTT treated PTC, culture of DTT treated explanted implants significantly improved the diagnosis of PJI (P = 0.03).ConclusionsWe could verify that DTT can be used to improve culture outcome in laboratories where biofilm detaching sonication techniques are not available for infected implants. In addition, we showed that it is possible to use DTT for treating tissue biopsies, but larger studies are required to confirm our findings.     

显微超声处理钙化根管的疗效评价

目的 评价显微超声技术处理钙化根管的临床疗效,以期为老年人钙化根管治疗提供临床参考.方法 选择102例牙髓炎或根尖周炎患者,年龄45～ 78岁,共119个钙化根管,均为采用常规根管治疗方法不能疏通的根管.在根管显微镜下使用超声器械进行根管再疏通治疗,去除髓腔内及根管颈、中段钙化组织,并比较其钙化根管各部位的疏通率.结果 99个钙化根管成功再疏通,疏通率为83％,前磨牙及磨牙组疏通率[分别为12/15、77％(43/56)]差异无统计学意义(x2=1.35,P＞0.05);上、下颌钙化根管疏通率[分别为84％(61/73)、83％ (38/46)]差异无统计学意义(x2=1.21,P＞0.05).根管颈段钙化的疏通率为93％(78/84),与根管中、尖段钙化比较差异具有统计学意义(P＜0.01),钙化部位靠近根尖时疏通率明显下降.结论 根管显微镜和超声器械的使用有助于提高老年患者钙化阻塞根管的疏通率,可有效地提高根管治疗的成功率.