不同起搏模式对老年人血浆内皮素1和一氧化氮水平的影响

目的观察老年患者置入具有工作模式转换功能的双腔起搏器术后心室起搏百分比与血浆内皮素1及NO水平的关系。方法入选置入双腔起搏器的老年患者24例,分为A组12例和D组12例。采用自身前后交叉对照研究方法,观察同一患者在心房按需型起搏(AAI)SafeR和房室全能型起搏(DDD)工作模式下的心室起搏百分比,检测患者内皮素1及NO水平并分析两者的关系。结果与术前比较,A组和D组术后3、6个月内皮素1及NO水平明显升高;与术后3个月比较,A组和D组术后6个月内皮素1水平明显升高[(1.02±0.21)μg/L vs(0.98±1.00)μg/L,(2.35±0.96)μg/L vs(2.31±1.07)μg/L,P<0.05]。与DDD模式比较,AAISafeR模式时心室感知百分比明显升高,心室起搏百分比明显降低(P<0.01)。相关分析显示,心室起搏百分比与内皮素1及NO水平呈正相关(r=0.125,P<0.01)。结论 AAISafeR模式可有效减少心室起搏百分比,心室起搏可能产生起搏依赖性的心功能损害。     

不同起搏模式对减少心室起搏比例的临床观察

目的 观察患者置入具有工作模式转换功能的双腔起搏器对减少右心室起搏的临床疗效.方法 入选符合双腔起搏器置入指征的患者126例,采用随机、单盲、自身前后交叉对照研究方法,观察同一患者在心房按需型起搏模式(AAISafeR)和房室全能型起搏模式(DDD)2种工作模式下心室起搏百分比的比例,随访3个月.进行ECG和超声心动图的检查,分析心室起搏百分比与心房的相关性.结果 与DDD比较,AAISafeR模式下心室感知百分比明显增加(34.61±9.82)%vs(73.18±13.08)%,差异有统计学意义(P＜0.05),心室起搏百分比明显减少(83.71±11.76)%vs(23.61±7.05)%,差异有统计学意义(P＜0.05),AAISafeR模式减少右心室起搏60.1%.相关分析显示,左心室舒张末径与心室起搏百分比呈正相关(r=0.398,P=0.0003),LVEF与心室起搏百分比之问无显著相关关系(r=-0.13,P=0.26).结论 AAISafeR模式可有效减少心室起搏百分比,可能影响心腔结构短期内重构,但尚未引起心室功能的改变.     

一种新的双腔起搏模式——AAISafeR与DDD模式的对比临床研究

目的评价存在自身房室传导置入双腔起搏器的患者,分别以DDD模式和AAISafeR模式工作3个月后心室起搏百分比以及临床指标。方法因病窦综合征置入Ela Symphony D 2450 DR2550系列双腔起搏器的患者30例,随机分为两组DDD组和AAISafeR组,3个月后交叉程控为AAISafeR和DDD,再随访3个月。结果没有观察到与AAISafeR有关的不良反应;AAISafeR模式能显著降低心室起搏的百分比51.3%(2%～91%)与0.9%(0～3%),(P=0.001);2.94%(0～18%)与41.18%(0～65%),(P=0.000);DDD模式工作3个月,左房直径、左室舒张末径、左室收缩末径均比术前增加,左室射血分数降低,差异有显著性,AAI SafeR模式工作3个月,除左房内径明显增大外,其余指标无明显改变;30例患者,在6个月的随访中,21例因不同程度的房室传导阻滞,AAI模式暂时转换为DDD模式。结论AAISafeR起搏模式能够有效降低心室起搏的百分比;AAISafeR起搏模式能够在出现房室传导阻滞的情况下,迅速安全的转换为DDD模式。     

心脏起搏器自动化功能对老年患者心功能的影响

目的观察具有自动AV间期搜索和起搏模式策略自动化功能的双腔心脏起搏器对老年患者减少心室起搏的有效性。方法选择置入DDD/R型双腔心脏起搏器的老年病态窦房结综合征(SSS)患者123例,分为实验组66例,平均年龄(76.5±6.8)岁,置入具备自动AV间期搜索和模式策略功能的美敦力公司Adapta系列起搏器;对照组57例,平均年龄(73.1±7.4)岁,置入不具备上述2种功能的美敦力公司Sigma AED、MED系列起搏器。术后1年内随访,观察心功能(NYHA)、程控获取右心室起搏(VP)百分比、心脏彩色超声心动科进行左心房内径(LAD)、左心室舒张末内径(LVEDD)的测量,计算LVEF,抽血检测N末端前体钠尿肽(NT-proBNP)水平,并进行对比。结果与对照组比较,实验组术后1年VP百分比降低[(39.7±35.2)%vs(91.7±2.6)%,P=0.02],LVEDD、LAD、LVEF均明显改善,差异有统计学意义[(51.5±3.9)mmvs(53.9±3.6)mm,(38.2±2.6)mmvs(42.0±4.5)mm,(54.8±7.7)%vs(50.1±12.3)%,P<0.05,P<0.01),实验组术后1年NT-proBNP水平较对照组明显降低[(180.2±19.4)ng/Lvs(269.2±23.6)ng/L,P<0.01]。结论具有起搏自动AV间期搜索和模式策略自动化功能的双腔起搏器可减少老年SSS患者VP百分比,改善心功能。     

高龄患者长期置入不同类型心脏起搏器对心脏功能的影响

目的探讨长期(≥2年)置入不同类型起搏器对高龄患者心脏功能的影响。方法选择高龄起搏器置入患者53例,根据置入类型不同分为单腔起搏组28例,双腔起搏组25例,另选取无明显心脏基础病的高龄患者30例(对照组)。观察各组超声心动图指标包括左心室收缩末容积(LVESV)、左心室舒张末容积(LVEDV)、LVEF,采用SF-36量表评价患者的生活质量。结果 LVEF单腔起搏组随访结束较置入前、双腔起搏组及对照组明显降低[(53.84±8.47)%vs(59.56±7.88)%,(59.45±8.15)%,(64.11±5.64)%,P<0.05],LVESV较置入前、双腔起搏组及对照组明显升高[(47.73±13.33)ml vs(39.27±9.79)ml、(38.88±12.15)ml及(34.50±9.95)ml,P<0.05]。结论单腔起搏器长期置入可降低高龄患者心脏的收缩功能,而双腔起搏器则更有优势。     

心室起搏管理功能降低病窦综合征患者高比例的右室起搏

目的评估具有心室起搏管理(MVP)功能的双腔起搏器对高比例右室起搏的病窦综合征(SSS)患者的疗效。方法 35例SSS患者,房室传导正常或合并间歇性房室传导阻滞(AVB),至少植入了两年双腔起搏器(DDD/R),并计划更换,入组前1个月以上的心室起搏比例超过40%。均植入具有MVP功能的双腔起搏器,随机程控MVP启动(MVP on组,n=17)或者关闭(MVP off组,n=18)。术前、术后6个月行血浆脑钠肽(BNP)测定;心脏超声测定左室收缩末期内径(LVESD),左室舒张末期内径(LVEDD),左室射血分数(LVEF);并于术后6个月程控起搏器了解右室起搏比例、心房高频事件。结果术前两组血浆BNP及LVESD、LVEDD、LVEF比较无显著差异(P>0.05);术后两组有关心脏超声指标无明显变化(P>0.05)。MVP on组术后较术前血浆BNP有明显下降(P﹤0.05),与MVP off组比较,MVP on组术后右室起搏百分比、心房高频事件发生率均有显著下降(2.6%±0.6%vs 48.4%±10.5%,15.7%±2.3%vs 62.0%±7.8%;P﹤0.01)。结论具有MVP功能的DDD/R起搏器能降低高比例右室起搏的SSS的右室起搏比例及心房高频事件的发生率。     

AAISafeR起搏模式自身对照研究

目的分析患者置入具有AAISafeR功能的Symphony2450起搏器后,短期内心脏结构和功能改变的特点及其与心室起搏百分比之间的关系。方法共入选22例患者,采用随机、单盲、自身前后交叉对照原则,观察同一患者在不同起搏模式下(AAISafeR和DDD)左房内径(LAD)、左室舒张末径(LVEDV)、左室收缩末径(LVESV)及左室射血分数(LVEF)的变化。结果不同起搏模式分别观察3个月后,LAD缩小(38.5±5.7mmvs39.7±4.5mm,P<0.05),但LVEDV、LVESV及LVEF变化不大。与DDD模式相比,AAISafeR模式下心室起搏、感知百分比有显著性差异(分别为67.49%±13.09%,43.89%±12.28%vs45.23%±11.15%,64.88%±15.08%,P均<0.05)。结论AAISafeR模式可有效减少心室起搏的百分比,较高比例的心室起搏百分比短期内(3个月)可影响心腔结构的重塑,但尚未引起心室功能的改变。     

双腔起搏器自动房室间期搜索功能的临床随访观察

目的 观察双腔起搏器自动房室间期搜索功能(AV Search)减少心室起搏的有效性及对血流动力学和快速房性心律失常的影响.方法 对两种DDD/R起搏器97例(有AV Search功能47例,无AV Search功能50例)患者术后半年内随访观察.结果 有AV Search功能组术后1、3、6个月右心室起搏百分比明显小于无AV Search功能组[(19.2±5.6)%vs(80.4±10.2)%,(17.8±6.6)%vs(75.3±9.5)%,(17.4±7.3)%VS[76.2±8.6]%,P<0.05].有AV Search功能组心脏指数、每搏量、左心室舒张末内径、左心房内径及患者心功能分级均无明显改善(P>0.05);而左心窒射血分数则高于无AV Search功能组(P<0.05).高频心房事件也显著减少((31±9)vs(49±11),P<0.05].结论 有AV Search功能DDD/R双腔起搏器在减少非必须的心室起搏,改善血流动力学,减少高频心房事件方面优于与无AV Search功能DDD/R起搏器.     

心室累积起搏百分数与血浆脑钠素水平的相关性研究

目的探讨接受双腔起搏治疗的病窦综合征患者术后心室累积起搏百分数与血浆脑钠素(BNP)浓度的关系。方法入选156例接受心脏起搏治疗的病窦综合征患者,术后随访时,通过酶联免疫吸附法(ELISA)测量患者血浆BNP水平,通过起搏器程控仪获取储存于起搏器中的心室累积起搏百分数,并分析两者之间的关系。结果经过中位数为65d的随访观察,双腔起搏患者术后血浆BNP水平较其术前显著增高,分别为(69.29±18.24)pg/ml和(54.47±17.15)pg/ml,P<0.01,心室累积起搏百分数与血浆BNP水平的相关系数r=0.569,P<0.01。结论心室累积起搏百分数与血浆BNP水平显著正相关,提示心室起搏可产生起搏依赖性的心功能损害。     

永久性心脏起搏对血浆脑钠尿肽的影响及贝那普利的干预作用

目的: 研究不同起搏模式、不同心室起搏百分比对永久性心脏起搏患者血浆脑钠尿肽（BNP）浓度的影响,及贝那普利对该类患者心功能的干预作用。方法: 入选2006年1月~2007年10月于我院行永久性心脏起搏的患者120例,其中VVI起搏62例DDD起搏58例,所有患者随机分为服用贝那普利组（干预组）及未服用贝那普利组（非干预组）,每组根据起搏模式不同分为VVI起搏亚组及DDD起搏亚组。分别于起搏前、起搏后6个月检测血浆BNP浓度。结果: VVI起搏患者血浆BNP浓度大于DDD起搏患者（P<0.05）;高心室起搏百分比患者血浆BNP浓度大于低心室起搏百分比患者（P<0.05）;干预组血浆BNP浓度显著低于非干预组（P<0.05）。结论: 起搏后血浆BNP浓度增加,且随着心室起搏百分比的增高而增高,但DDD起搏优于VVI起搏;贝那普利可以延缓永久性心脏起搏患者血浆BNP浓度的增加量。     

Control of intraabdominal hemorrhage and shock: a comparison of fluid resuscitation, MAST, and balloon occlusion

Our study examined the efficacy of four treatment modalities in controlling hemorrhage and achieving hemodynamic stabilization in hemorrhagic shock: intravenous fluid replacement (IV); military antishock trousers used concomitantly with fluids (MAST); balloon occlusion at the level of the diaphragm with concomitant fluid replacement (balloon); and a combination of MAST inflation, balloon occlusion, and fluid resuscitation (MAST and balloon). Twenty-eight mongrel dogs were anesthetized, and the spleen was exposed and completely crushed. The abdomen was closed, and treatment was initiated and continued for four hours or until the dog died. For all conditions the hematocrit dropped during the course of the experiment; balloon occlusion was effective at slowing this drop (P less than .0001), but MAST had no statistically significant effect. Animals with balloons bled more slowly into the abdominal cavity than did animals in the other two groups (P less than .0001). MAST also were effective at slowing the bleeding (P less than .05). Of the balloon and the MAST and balloon dogs, all except one survived the entire four hours; this difference between balloon and nonballoon dogs is significant (P = .002). MAST did not have a statistically significant effect on survival. Perfusion pressure (PP) declined during the course of the experiment, and the balloon was effective at slowing this decline (P less than .0001); none of the other comparisons was statistically significant.     

A Call to Action to Enhance Filovirus Disease Outbreak Preparedness and Response

The frequency and magnitude of recognized and declared filovirus-disease outbreaks have increased in recent years, while pathogenic filoviruses are potentially ubiquitous throughout sub-Saharan Africa. Meanwhile, the efficiency and effectiveness of filovirus-disease outbreak preparedness and response efforts are currently limited by inherent challenges and persistent shortcomings. This paper delineates some of these challenges and shortcomings and provides a proposal for enhancing future filovirus-disease outbreak preparedness and response. The proposal serves as a call for prompt action by the organizations that comprise filovirus-disease outbreak response teams, namely, Ministries of Health of outbreak-prone countries, the World Health Organization, Médecins Sans Frontières, the Centers for Disease Control and Prevention—Atlanta, and others.     

Interplay between interferon-mediated innate immunity and porcine reproductive and respiratory syndrome virus

Innate immunity is the first line of defense against viral infection, and in turn, viruses have evolved to evade host immune surveillance. As a result, viruses may persist in host and develop chronic infections. Type I interferons (IFN-α/β) are among the most potent antiviral cytokines triggered by viral infections. Porcine reproductive and respiratory syndrome (PRRS) is a disease of pigs that is characterized by negligible induction of type I IFNs and viral persistence for an extended period. For IFN production, RIG-I/MDA5 and JAK-STAT pathways are two major signaling pathways, and recent studies indicate that PRRS virus is armed to modulate type I IFN responses during infection. This review describes the viral strategies for modulation of type I IFN responses. At least three non-structural proteins (Nsp1, Nsp2, and Nsp11) and a structural protein (N nucleocapsid protein) have been identified and characterized to play roles in the IFN suppression and NF-κB pathways. Nsp's are early proteins while N is a late protein, suggesting that additional signaling pathways may be involved in addition to the IFN pathway. The understanding of molecular bases for virus-mediated modulation of host innate immune signaling will help us design new generation vaccines and control PRRS.     

Disease Pandemics and Major Epidemics Arising From New Encounters between Indigenous Viruses and Introduced Crops

Virus disease pandemics and epidemics that occur in the world’s staple food crops pose a major threat to global food security, especially in developing countries with tropical or subtropical climates. Moreover, this threat is escalating rapidly due to increasing difficulties in controlling virus diseases as climate change accelerates and the need to feed the burgeoning global population escalates. One of the main causes of these pandemics and epidemics is the introduction to a new continent of food crops domesticated elsewhere, and their subsequent invasion by damaging virus diseases they never encountered before. This review focusses on providing historical and up-to-date information about pandemics and major epidemics initiated by spillover of indigenous viruses from infected alternative hosts into introduced crops. This spillover requires new encounters at the managed and natural vegetation interface. The principal virus disease pandemic examples described are two (cassava mosaic, cassava brown streak) that threaten food security in sub-Saharan Africa (SSA), and one (tomato yellow leaf curl) doing so globally. A further example describes a virus disease pandemic threatening a major plantation crop producing a vital food export for West Africa (cacao swollen shoot). Also described are two examples of major virus disease epidemics that threaten SSA’s food security (rice yellow mottle, groundnut rosette). In addition, brief accounts are provided of two major maize virus disease epidemics (maize streak in SSA, maize rough dwarf in Mediterranean and Middle Eastern regions), a major rice disease epidemic (rice hoja blanca in the Americas), and damaging tomato tospovirus and begomovirus disease epidemics of tomato that impair food security in different world regions. For each pandemic or major epidemic, the factors involved in driving its initial emergence, and its subsequent increase in importance and geographical distribution, are explained. Finally, clarification is provided over what needs to be done globally to achieve effective management of severe virus disease pandemics and epidemics initiated by spillover events.     

Barrett's Esophagus: Where Do We Stand?

Barrett''s esophagus (BE) is a precursor for esophageal adenocarcinoma, which has an increased incidence rate over the last few decades. Its importance stems from the poor five-year survival of esophageal adenocarcinoma and current data that suggest a survival benefit when surveillance programs are implemented. In this review, we will cover the pathophysiology and natural history of BE and the different endoscopic findings. The prevalence of BE in different geographic areas and the incidence of high-grade dysplasia and adenocarcinoma in this patient population is reviewed. Recent recommendation for screening and surveillance of BE has been covered in this review as well as the efficacy of nonconventional imaging modalities and endoscopic ablation therapies.     

The Technology Transfer from Europe to China in the 17th–18th Centuries: Non-Invasive On-Site XRF and Raman Analyses of Chinese Qing Dynasty Enameled Masterpieces Made Using European Ingredients/Recipes

Two masterpieces of the Qing Dynasty (1644–1912 CE), one in gilded brass (incense burner) decorated with cloisonné enamels stylistically attributed to the end of the Kangxi Emperor’s reign, the other in gold (ewer offered by Napoleon III to the Empress as a birthday present), decorated with both cloisonné and painted enamels bearing the mark of the Qianlong Emperor, were non-invasively studied by optical microscopy, Raman microspectroscopy and X-ray microfluorescence spectroscopy (point measurements and mapping) implemented on-site with mobile instruments. The elemental compositions of the metal substrates and enamels are compared. XRF point measurements and mappings support the identification of the coloring phases and elements obtained by Raman microspectroscopy. Attention was paid to the white (opacifier), blue, yellow, green, and red areas. The demonstration of arsenic-based phases (e.g., lead arsenate apatite) in the blue areas of the ewer, free of manganese, proves the use of cobalt imported from Europe. The high level of potassium confirms the use of smalt as the cobalt source. On the other hand, the significant manganese level indicates the use of Asian cobalt ores for the enamels of the incense burner. The very limited use of the lead pyrochlore pigment (European Naples yellow recipes) in the yellow and soft green cloisonné enamels of the Kangxi incense burner, as well as the use of traditional Chinese recipes for other colors (white, turquoise, dark green, red), reinforces the pioneering character of this object in technical terms at the 17th–18th century turn. The low level of lead in the cloisonné enamels of the incense burner may also be related to the use of European recipes. On the contrary, the Qianlong ewer displays all the enameling techniques imported from Europe to obtain a painted decoration of exceptional quality with the use of complex lead pyrochlore pigments, with or without addition of zinc, as well as cassiterite opacifier.