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1.
To prove that protein-lipid emulsions can be echogenic, we made two lipid-in-water emulsions. The first emulsion was composed of lipid micelles approximately 10 microns in diameter. The second emulsion was composed of micelles approximately 100 microns in diameter. The first emulsion was anechoic; the second emulsion was echogenic. These results are consistent with the physical laws governing the scatter of ultrasound and demonstrate that collagen containing connective tissue is not necessary for echoes. In addition, these data support the hypothesis that the wide differences in echogenicity of fatty tissues is due to the differences in the thickness of their connective tissue stromata.  相似文献   

2.
Identification of risk markers based on quantitative ultrasound texture analysis of carotid plaques has the ability to define vulnerable components that correlate with increased cardiovascular risk. However, data describing factors with the potential to influence the measurement variability of risk markers are limited. The aim of this study was to evaluate the influence of electrocardiogram-guided image selection, plaque echogenicity and area on carotid plaque risk markers and their variability in asymptomatic carotid plaques. Plaque risk markers were measured in 57 plaques during three consecutive heartbeats at two cardiac cycle time instants corresponding to the electrocardiogram R-wave (end diastole) and end of T-wave (end systole), resulting in six measurements for each plaque. Risk marker variability was quantified by computing the coefficient of variation (CV) across the three heartbeats. The CV was significantly higher for small plaques (area <15?mm2, 10%) than for large plaques (area >15?mm2, 6%) (p?<?0.001) in measurements of area, and the CV for measurements of gray-scale median were higher for echolucent plaques (<40, 15%) than for echogenic plaques (>40, 9%) (p?<?0.001). No significant differences were found between systole and diastole for the mean of any risk marker or the corresponding CV value. However, in a sub-analysis, the echolucent plaques were found to have a higher CV during systole compared with diastole. The variability also caused plaque type reclassification in 16% to 25% of the plaques depending on cutoff value. The results of this study indicate that echolucent and small plaques each contribute to increased risk marker variability. Based on these results, we recommend that measurements in diastole are preferred to reduce variation, although we found that it may not be possible to characterize small plaques accurately using contemporary applied risk markers.  相似文献   

3.
目的:探讨超声微泡空化对晚期胰腺癌患者肿瘤病灶血流灌注的增强效应。方法:选取经病理组织学或细胞学证实的胰腺癌患者21例,在每次临床化疗结束后120 min(白蛋白紫杉醇联合吉西他滨、FOLFIRINOX 方案、白蛋白紫杉醇联合替吉奥)内对病灶进行超声微泡空化治疗,空化治疗前后分别行超声造影动态观察肿瘤血流灌注情况,并根据肿瘤区域时间-强度曲线,分析峰值强度、曲线下面积等指标。结果:21例胰腺癌患者共计84次化疗联合超声微泡空化治疗,空化治疗后胰腺癌病灶的峰值强度由109.19 ± 2.64增加到110.62 ± 2.70(P = 0.16),曲线下面积由4752.76 ± 149.53增加到4863.67 ± 159.77(P = 0.33),二者均无统计学意义。结论:超声微泡空化治疗可增加胰腺癌患者肿瘤病灶的血流灌注量,有望改善胰腺癌因乏氧、乏血供导致的化疗抵抗问题。  相似文献   

4.
We sought to determine whether transtemporal-applied 1-MHz ultrasound-induced microbubble destruction may be a safe method of transiently altering blood brain barrier (BBB) permeability for drug delivery in a large animal model. Endothelial cells are an integral component of the BBB but also prevent passage of potentially therapeutic drugs. Ultrasound-mediated destruction (UMD) of microbubbles has been shown to disrupt this barrier in small animals when ultrasound is delivered through bone windows. However, the effects of temporal bone attenuation and scattering in a large animal may limit the clinical application of such a technique. Twenty-four pigs were studied. One-MHz pulsed-wave ultrasound at 2.0 W/cm(2) (20% duty cycle) across the temporal bone was applied for 30 min after intravenous injections of either albumin-coated perfluorocarbon microbubble (PESDA, 8 pigs), lipid-encapsulated perfluorocarbon microbubbles (LEMB, 8 pigs) or ultrasound alone (8 pigs). BBB leak was quantified at 30 and 120 min after insonation using Evans blue. Serial magnetic resonance imaging (MRI) was performed in nine of the pigs (3 for each group) to quantify Gadolinium leak within the parenchyma. Peak negative pressures decreased ten-fold when ultrasound was transmitted across the pig temporal bone. Despite this, spectrophotometric analysis showed that both IV LEMB and PESDA combined with transtemporal ultrasound resulted in a significant increase in Evans blue extravasation across BBB of the treated side at 30 min after insonation (p < 0.001; compared with ultrasound alone) but not at 120 min. There was significant retention of Gadolinium within the insonified parenchyma at 60 and 90 min after insonation, but not at 120 min. Oxygen saturation and arterial pressures were not changed after any microbubble injection. Intravenous microbubbles, combined with transtemporal ultrasound, can transiently increase BBB permeability in a large animal. This induced opening of BBB is reversible and may be a safe noninvasive method of achieving drug or gene delivery across the BBB.  相似文献   

5.
目的 探讨实时三维诊断超声激励瘤内注射微泡增强VX2移植瘤化疗效果的价值。方法 将24个兔VX2移植瘤模型随机分为4组,每组6只,分别为空白对照组(A组)、单纯多柔比星(Dox)组(B组)、实时三维诊断超声+微泡组(C组)、实时三维诊断超声+微泡+Dox组(D组)。对实验兔静脉注射Dox 1.2 ml/kg,瘤内注射微泡、约为肿瘤体积的1/2,辐照时间为20 min,机械指数(MI)1.3。于第1、3、5、8天对每组肿瘤进行治疗,共治疗4次。治疗后第10天剥离肿瘤,计算各组肿瘤体积总体生长率。结果 治疗后第10天,D组肿瘤体积明显小于其余3组(P<0.05);4组肿瘤体积总体生长率分别为A组100%,B组15.11%,C组118.22%,D组-30.81%。D组肿瘤体积在治疗后1~3天内略有增大,之后明显下降。结论 实时三维诊断超声激励瘤内注射微泡联合静脉注射Dox能够明显抑制兔VX2移植瘤的生长。  相似文献   

6.
To make stable and biocompatible non-viral gene carriers for therapeutic gene therapy, we developed a cationic lipid-based emulsion (CLE) prepared by an oil-in-water (O/W) emulsion method, wherein squalene oil was used as an oil core and the cationic lipid, 1,2-dioleoyl-sn-glycero-3-trimethylammonium-propane (DOTAP), was employed as an emulsifier. To evaluate in vivo characteristics such as toxicity and time-dependent gene expression, a bioluminescence reporter gene in pCMV-luc plasmid DNA was simply mixed with CLE in aqueous condition, resulting in a CLE/DNA complex. The CLE/DNA complex was optimized to form a compact and stable nano-sized particle by adding different amounts of plasmid DNA, and an optimal cationic lipid-to-DNA (C/D) weight ratio of 4 was identified. Freshly prepared CLE/DNA complex, with a C/D of 4, showed a high transfection efficiency and minimal cytotoxicity in vitro, compared to controls of a liposome (DOTAP)/DNA complex and a branched poly(ethyleneimine) (Mw = 25 kDa) (bPEI)/DNA complex, respectively. The in vivo characteristics of the CLE/DNA complex were evaluated after intravenous injection into Balb/c mice. Time-dependent gene expression data in vivo were obtained using a non-invasive, whole animal bioluminescence imaging system. These data showed that the CLE/DNA complex offered prolonged high-level gene expression for 1 week, particularly in the liver and spleen. On the other hand, the controls of DOTAP/DNA complex and bPEI/DNA complex showed a relatively lower gene expression, because of the unstable and toxic properties of the control carriers. Our in vivo gene expression data demonstrate the potential of the CLE/DNA complex as a non-viral gene carrier for in vivo gene delivery.  相似文献   

7.
目的 应用二维超声斑点追踪显像技术评价超声微泡造影剂介导rAAV2-SERCA2a基因靶向治疗心肌梗死大鼠左心室功能的疗效.方法 健康雄性SD大鼠35只,随机分为3组:假手术组、心肌梗死组和基因治疗组.心肌梗死组及基因治疗组结扎冠状动脉左前降支近端,造成前壁心肌梗死.假手术组单纯开胸不结扎冠状动脉.4周时,基因治疗组注射rAAV2-SERCA2a与造影剂混合液,假手术组及心肌梗死组仅注射造影剂,以上各组均给予心肌定点超声辐照.干预4周时,测量各组大鼠左心室短轴观乳头肌水平径向应变率(radial strain rate,SRrad)和圆周应变率(circumferential strain rate,SRcir)的收缩期峰值(SRrad-S,SRcir-S)及舒张早期峰值(SRrad-E,SRcir-E)以及左室心肌扭转角度等.结果 干预4周时,基因治疗组各节段SRcir-S、SRcir-E、SRrad-S、SRrad-E以及左室扭转角度较心肌梗死组增加(P<0.01),与假手术组差异无统计学意义.结论 超声微泡造影剂介导rAAV2-SERCA2a基因转导至心肌组织,可有效改善心肌梗死大鼠左室心肌功能.  相似文献   

8.
Objectives The study investigated the use of an intravenous lipid emulsion containing medium chain tryglycerides (MCTs) in critically ill patients, and compared the effects with those of a conventional long chain triglyceride (LCT) preparation.Design Patients received a parenteral nutrition regime including either 500 ml 20% Lipofundin MCT/LCT (1/1) per day, or 500 ml 20% Lipofundin S (LCT) infused over 8 h each evening.Setting The patients were receiving treatment, including assisted ventilation, in the Intensive Care Unit of a large teaching hospital. All patients on this unit for at least 3 days and who were likely to receive parenteral nutrition for at least a week were considered, unless they had severe renal or liver disease, or trauma/major surgery in the previous 3 days. Because ICU patients are a heterogenous group, subjects were randomised within clinical groups to receive either lipid. There were 24 patients entered into the study and the data on 20 matched patients is reported.Measurements and results Blood specimens were collected pre-TPN, daily at 0800 and after 5 h lipid infusion on days 1 and 6. Urine collections (24 h) were also performed. There were no apparent adverse effects due to the new MCT/LCT emulsion. Plasma ketone and glycerol concentrations were higher during MCT/LCT infusion, but 8 h post infusion plasma levels of ketones, triglycerides, non-esterified fatty acids and glucose were similar. Urinary carnitine excretion was high in all patients and was not significantly different between the groups. Nitrogen balance was less negative in patients receiving MCT/LCT on days 6 and 9.Conclusion MCTs are rapidly hydrolysed and oxidised to fatty acids and ketones which can be readily utilised. This study indicates that intravenous lipid emulsion containing MCT are safe in critically ill patients and may have advantages over LCT. The number and range of patients studied was, however, small and larger studies are needed.  相似文献   

9.
Context. Circulatory shock is a major cause of mortality in glyphosate-surfactant herbicide (GlySH) poisoning, and this condition responds poorly to conventional therapies. We report a case of GlySH poisoning with shock that was refractory to vasopressors but responsive to intravenous fat emulsion (IFE). Case details.?A 52-year-old man was brought to the emergency department by ambulance. He was found unconscious in his living room along with an empty bottle of GlySH herbicide, which contained glyphosate, polyoxyethyleneamine (POEA) surfactant, and water. He was drowsy at presentation. His heart rate was 44 beats/min, his blood pressure could not be measured with an arm cuff, but he had a palpable femoral pulse. After about 2.5 h of supportive care after admission, he remained hypotensive, and his systolic blood pressure was 80 mmHg. A 500 mL bottle of 20% IFE product was prepared. As a bolus, 100 mL of IFE was injected, and the remaining 400 mL was then infused. His blood pressure was 100/60 mmHg 1 h after the bolus injection. At 5 h after IFE injection, his blood pressure reached 160/100 mmHg and vasopressors were tapered. Conclusion.?IFE should be considered in cases of refractory hemodynamic instability caused by GlySH after aggressive fluid and vasopressor support.  相似文献   

10.
目的构建携Sialyl Lewisx和抗P-选择素单抗靶向微泡,用定点追踪技术在体外高剪切应力下评价其黏附行为。方法构建携Sialyl Lewisx靶向微泡(MB-S)、携抗P-选择素单抗靶向微泡(MB-P)、携Sialyl Lewisx和抗P-选择素单抗双配体靶向微泡(MB-D)。利用平行板流动腔和Image-Pro-Plus软件绘制微泡滚动的时间-速度折线图。微泡第1帧的速度为V1,第2帧至黏附前倒数第3帧的平均速度为V2,黏附前倒数第2帧的速度为V3。结果 MB-P高速滚动,速度骤降为0;MB-S从高速平缓过渡到低速,再渐降低至0;MB-D从高速过渡到低速,再骤降为0。3种微泡V1差异无统计学意义(P>0.05);MB-P的V2明显高于MB-S和MB-D(P<0.01);MB-S和MB-D间V2差异无统计学意义(P>0.05)。V3在3种微泡中的顺序为MB-P>MB-D>MB-S(P<0.01)。结论Sialyl Lewisx介导高效滚动,抗P-选择素单抗介导微泡速度的骤降,两者在微泡靶向黏附时可发挥互补作用。  相似文献   

11.
目的明确高呼气末正压(PEEP)条件下肺泡微循环的变化情况以及液体复苏在高PEEP情况下对肺泡微循环的影响。 方法选用北京当地的15条健康成年杂种狗进行实验,分别观察基线(PEEP 5 cmH2O,1 cmH2O=0.098 kPa)、高PEEP(平均动脉压下降≥20 mmHg,1 mmHg=0.133 kPa)及液体复苏后的呼吸、系统循环及肺泡微循环情况,肺泡微循环利用旁流暗视野成像(SDF)技术进行观察、留取视频结果,线下利用AVA3.2软件进行分析,不同条件下的实验数据之间的差异利用Wilcoxon秩和检验进行分析。 结果高PEEP可导致中心静脉压(CVP)升高(P=0.001)及心输出量(CO)下降(P=0.002),肺泡微循环表现为总微血管数量(TVDa,P=0.036)、灌注血管数量(PVDa,P=0.002)、灌注血管比例(PPVa,P=0.003)、血流状态(MFIa,P=0.002)显著下降,肺泡周围毛细血管密度下降不明显(TVDs,P=0.319);液体复苏恢复整体循环后,微循环参数均无显著改善。 结论过高的PEEP水平可导致肺泡微循环的显著恶化,通过液体复苏不能改善由此产生的微循环障碍。  相似文献   

12.
13.
Ultrasound-driven microbubble activities have been exploited to transiently disrupt the cell membrane (sonoporation) for non-viral intracellular drug delivery and gene transfection both in vivo and in vitro. In this study, we investigated the dynamic behaviors of a population of microbubbles exposed to pulsed ultrasound and their impact on adherent cells in terms of intracellular delivery and cell viability. By systematically analyzing the bubble activities at time scales relevant to pulsed ultrasound exposure, we identified two quantification parameters that categorize the diverse bubble activities subjected to various ultrasound conditions into three characteristic behaviors: stable cavitation/aggregation (type I), growth/coalescence and translation (type II) and localized inertial cavitation/collapse (type III). Correlation of the bubble activities with sonoporation outcome suggested that type III behavior resulted in intracellular delivery, whereas type II behavior caused the death of a large number of cells. These results provide useful insights for rational selection of ultrasound parameters to optimize outcomes of sonoporation and other applications that exploit the use of ultrasound-driven bubble activities.  相似文献   

14.
15.
We report a rare case of small bowel obstruction (SBO) caused by endometriosis in a postmenopausal woman. A 54‐year‐old postmenopausal woman presented with severe abdominal pain and vomiting. Before menopause, she sometimes had abdominal pain associated with menses. Axial multi‐dimensional CT images revealed a SBO with small nodules near the terminal ileum. The obstruction was diagnosed as being caused by small bowel endometriosis. Curved planar reconstruction images showed a complicated obstruction of the small intestine 15 cm from the terminal ileum. Based on the stenotic lesion, a SILS procedure was performed. The patient's SBO diagnosis was histologically confirmed as being caused by small bowel endometriosis. SILS was deemed to be a safe, feasible procedure for treating this bowel obstruction. Curved planar reconstruction images were useful in preoperative imaging and diagnosis of SBO, especially as they were able to highlight the constricting legion.  相似文献   

16.
Raoultella planticola is a gram-negative, encapsulated, aerobic bacterium within the Enterobacteriaceae family. It has been primarily described as pathogen in cases with pneumonia and gastrointestinal infections. Here we describe a case of severe pelvic cellulitis in a patient with neutropenia following induction therapy for myeloid sarcoma. The patient experienced a septic shock and was treated successfully with antibiotic therapy. A literature review is provided to put this case in context with previous reports on R. planticola. This report highlights that awareness for uncommon pathogens is crucial in the clinical management of infections in neutropenic patients.  相似文献   

17.
目的 了解儿童危重甲型H1N1流感合并急性呼吸窘迫综合征(ARDS)的临床特点,探讨救治措施.方法 前瞻性观察上海交通大学附属儿童医院收治的3例危重甲型H1N1流感的临床表现、化验检查、诊断、治疗转归.结果 实时RCT-PCR检测3例患者均为甲型H1N1流感感染.以发热、咳嗽起病,全身性炎症反应相对轻.病程4~6 d病情突然恶化,出现口唇发绀,呼吸急促.X线片显示双肺多叶渗出或弥漫性炎症阴影.入院时已发展为ARDS.采用奥司他韦,小潮气量(6 mL/kg)、适当高PEEP通气策略和相对保守液体等治疗,3例患儿中存活2例,死亡1例.结论 儿童危重甲型H1N1流感患儿,突然咳嗽加重和呼吸急促时,应高度怀疑ARDS.及时氧疗及呼吸支持,保守液体管理,预防继发感染等可能是关键治疗措施.需要积累更多病例资料来明确危重甲型H1N1流感特征和评价救治手段.  相似文献   

18.
AIM: To study a course and prognosis of ischemic heart disease (IHD) with stable angina pectoris (SAP) caused by stenotic coronary atherosclerosis (SCA) by 20-year follow-up data. MATERIAL AND DATA: Prognosis of survival was made in 318 patients with SAP due to SCA. RESULTS: The results of a 20-year study show that prognosis in IHD patients depends on SAP severity (by the functional class), exercise tolerance (by the exercise test), severity of coronary bed affection and of left ventricular contractility affection as assessed by coronary- and ventriculography. If lethality of the test subjects was not higher than in the population, the patient had good prognosis associated with one-vessel lesion, normal myocardial contractile function, high exercise tolerance, absence of the leading risk factors. CONCLUSION: The multivariance analysis with stepwise selection enabled the design of the model of the integral prognostic index (IPI) for the studied patients. The IPI index under 1.86 suggests a favourable prognosis, 1.87-2.33--an intermediate prognosis and in IPI higher than 2.34--unfavourable prognosis. Early surgery is recommended for patients with high IPI.  相似文献   

19.
Muñiz AE 《Resuscitation》2008,78(3):378-380
Bag-valve-mask ventilation is generally a safe, and often a life-saving procedure for children who are unable to oxygenate or ventilate by themselves. A case is presented which describes a malfunctioning expiratory valve in a disposable manual bag-valve-mask device resulting in a pneumomediastinum in a child. This is a rare cause of a false-negative colorimetric end-tidal carbon dioxide (ETCO(2)) reading after endotracheal intubation. However, it is important to recognize so that further adverse outcomes can be prevented.  相似文献   

20.
2010年10月,浙江省衢州市衢江区某乡镇中心学校发生一起水源污染引起的细菌性痢疾暴发疫情,共发病178例,无死亡病例,罹患率为13.8%,疫情波及小学部22个班级、幼儿园部2个班级和一些教职员工。细菌学检测显示水源细菌总数、大肠菌群、耐热大肠埃希菌均超标,采集的58份肛拭标本,37份检出宋内志贺菌,阳性率为63.79%。  相似文献   

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