CT定量分析在冠心病介入治疗前后血流灌注改变的评估价值

摘要 目的：探讨CT定量分析在冠心病介入治疗前后血流灌注改变的评估价值。方法：2018年2月到2020年11月选择在本院诊治的冠心病患者95例作为研究对象,所有患者都给予经皮冠状动脉介入治疗,在介入前1 d与介入后1个月进行CT定量与超声检查,随访介入后6个月的冠状动脉再狭窄情况并进行相关性分析。结果：所有患者都顺利完成介入治疗,介入期无严重并发症发生。95例患者介入后1个月的左室射血分数(ejectionfraction,EF)、左室短轴缩短率(fractionalshortening,FS)高于介入前1 d(P<0.05),介入前后左室等容舒张时间(iso-volumicrelaxationtime,IVRT)对比差异无统计学意义(P>0.05)。95例患者介入后1个月的心肌血流量(Myocardialbloodflow,MBF)、心肌血容量(Myocardialbloodvolume,MBV)高于介入前1d(P<0.05),达峰时间(Timetopeak,TTP)低于介入前1 d(P<0.05)。介入后随访6个月,冠状动脉再狭窄14例,再狭窄率14.7 %,其中中度狭窄12例,重度狭窄2例;Pearson分析显示冠心病患者介入前1 d的MBF、MBV、TTP与FS、EF都存在相关性(P<0.05);Logistic回归分析显示MBF、MBV、TTP、FS、EF为影响冠心病患者介入后随访再狭窄率的重要因素(P<0.05)。结论：CT定量分析在冠心病介入前后的应用能有效反映血流灌注改变情况,且与患者的心功能存在相关性,也可有效预测患者介入随访冠状动脉再狭窄发生情况。     

神经电生理在颅内动脉瘤夹闭术中联合颅内压、脑灌注压监测的应用效果研究

摘要 目的：探讨神经电生理在颅内动脉瘤夹闭术中联合颅内压（ICP）、脑灌注压（CPP）监测的应用效果。方法：选取2018年12月～2020年1月我院进行开颅手术治疗的颅内动脉瘤患者60例,采用简单随机化分组方法分为两组,每组30例。对照组实施颅内动脉瘤夹闭手术,观察组在对照组基础上,术中应用神经电生理、ICP、CPP监测。比较两组动脉瘤夹闭情况,术后第1 d新发神经功能缺损情况,术前、术后1 d、术后3个月格拉斯哥昏迷评分（GCS）、美国国立卫生研究院脑卒中量表（NIHSS）评分及术后3个月预后优良率。结果：两组动脉瘤均完全夹闭,观察组术后第1 d新发神经功能缺损率6.67%（2/30）低于对照组的26.67%（8/30）（P＜0.05）;术后1 d观察组GCS评分高于对照组,NIHSS评分低于对照组（P＜0.05）;排除失访病例后,观察组术后3个月GOS分级、mRS分级优良率分别为88.89%、88.89%,与对照组的88.00%、84.00%比较,差异无统计学意义（P＞0.05）。结论：采用神经电生理联合ICP、CPP监测,能够实时掌握颅内动脉瘤夹闭术患者脑组织血流情况,根据监测结果及时采取相应干预措施,可预防不可逆的脑缺血改变,改善术后早期患者意识状态,减少术后早期神经功能缺损的发生。     

莫西沙星联合纤维支气管镜药物灌注对耐多药肺结核患者T细胞亚群、肺功能和肝功能的影响

摘要 目的：探讨莫西沙星联合纤维支气管镜药物灌注对耐多药肺结核患者T细胞亚群、肺功能和肝功能的影响。方法：选取2017年2月~2018年12月期间我院收治的90例耐多药肺结核患者,根据随机数字表法分为对照组（n=45,常规基础治疗）和研究组（n=45,莫西沙星联合纤维支气管镜药物灌注）,比较两组患者痰菌转阴率、病灶吸收率、T细胞亚群、肺功能和肝功能。结果：研究组治疗6个月后的痰菌转阴率为88.89%（40/45）,高于对照组的68.89%（31/45）（P<0.05）。研究组治疗6个月后的病灶吸收率为84.44%（38/45）,高于对照组的64.44%（29/45）（P<0.05）。两组治疗6个月后第1 s用力呼气容积（FEV₁）、用力肺活量（FVC）、每分钟最大通气量（MVV）占预计值百分比、总蛋白(TP)、CD4⁺、CD4⁺/CD8⁺均升高,且研究组高于对照组（P<0.05）;丙氨酸氨基转移酶(ALT)、门冬氨酸氨基转移酶(AST)、CD8⁺均降低,且研究组低于对照组（P<0.05）。结论：莫西沙星联合纤维支气管镜药物灌注治疗耐多药肺结核,可有效阻止疾病进展,同时在改善患者T细胞亚群、肺功能和肝功能方面效果显著。     

Notes and queries

A method for making permanent whole mounts of flat and round worms is described. The specimens are mounted in a drop of acid fuchsin lacto-phenol on a slide and warmed for 6 hours at 60°C. The acid fuchsin is replaced by light cotton-blue (anilin blue, W. S.) in lacto-phenol, till the desired contrast is obtained. After this, the forms are mounted in pure lacto-phenol, using the coverglass. The margin of the coverglass is sealed with the sealing media devised by Dade and Waller (equal parts of damar balsam and beeswax)     

An ESR contrast agent is transported to rat liver through organic anion transporter

Carboxy PROXYL is a useful extracellular paramagnetic contrast reagent in electron spin resonance (ESR) and magnetic resonance imaging (MRI). Active transfer of the probe was investigated using an in situ liver model in rats. Carboxy PROXYL, a nitroxyl spin probe, was perfused into in situ liver perfusion system from Wistar rats. Concentration of nitroxyl form of the spin probe in effluent increased gradually after introducing perfusate with the spin probe and reached a plateau. The disappearance of Carboxy PROXYL from the perfusate was 40%, which could not be explained with its partition coefficient. Administration of non-selective inhibitors of organic anion transporters, p-aminohippuric acid and penicillin G, inhibited competitively and in a dose dependent manner the transfer of Carboxy PROXYL into rat liver in situ, resulting in increases of Carboxy PROXYL in the effluent. The results demonstrate that there is an active transfer system of an ESR contrast reagent into in situ rat liver through organic anion transporters.     

Blood Perfusion in a Murine Fibrosarcoma Tumor Model After Direct Current Electrotherapy a Study with 86Rb Extraction Technique

Electrotherapy with low-level direct current (DC) can induce antitu-mor effects in various tumor models. Applied in combination with certain anticancer drugs, it can significantly increase their effectiveness. It has been suggested that the demonstrated effects of electrotherapy arise from its modification of tumor blood flow. The effect of such treatment on blood perfusion of solid subcutaneous Sa-1 fibrosarcoma tumors in A/J mice was investigated with a ⁸⁶rubidium extraction technique. Following electrotherapy, the relative tissue perfusion of tumors was decreased by more than 50%. Three days after treatment, partial reperfusion of tumors occurred. The dynamics of the perfusion changes induced by electrotherapy are in agreement with tumor growth dynamics following this procedure. The effect of electrotherapy on the blood supply of tumors may be the major mechanism of antitumor action in our model. Electrotherapy could be useful as an adjuvant local procedure to other treatment modalities that require a hypoxic environment for their effectiveness.     

Steps for the Autologous Ex vivo Perfused Porcine Liver-kidney Experiment

The use of ex vivo perfused models can mimic the physiological conditions of the liver for short periods, but to maintain normal homeostasis for an extended perfusion period is challenging. We have added the kidney to our previous ex vivo perfused liver experiment model to reproduce a more accurate physiological state for prolonged experiments without using live animals. Five intact livers and kidneys were retrieved post-mortem from sacrificed pigs on different days and perfused for a minimum of 6 hr. Hourly arterial blood gases were obtained to analyze pH, lactate, glucose and renal parameters. The primary endpoint was to investigate the effect of adding one kidney to the model on the acid base balance, glucose, and electrolyte levels. The result of this liver-kidney experiment was compared to the results of five previous liver only perfusion models. In summary, with the addition of one kidney to the ex vivo liver circuit, hyperglycemia and metabolic acidosis were improved. In addition this model reproduces the physiological and metabolic responses of the liver sufficiently accurately to obviate the need for the use of live animals. The ex vivo liver-kidney perfusion model can be used as an alternative method in organ specific studies. It provides a disconnection from numerous systemic influences and allows specific and accurate adjustments of arterial and venous pressures and flow.     

Computational fluid dynamic analysis of bioprinted self-supporting perfused tissue models

Natural tissues are incorporated with vasculature, which is further integrated with a cardiovascular system responsible for driving perfusion of nutrient-rich oxygenated blood through the vasculature to support cell metabolism within most cell-dense tissues. Since scaffold-free biofabricated tissues being developed into clinical implants, research models, and pharmaceutical testing platforms should similarly exhibit perfused tissue-like structures, we generated a generalizable biofabrication method resulting in self-supporting perfused (SSuPer) tissue constructs incorporated with perfusible microchannels and integrated with the modular FABRICA perfusion bioreactor. As proof of concept, we perfused an MLO-A5 osteoblast-based SSuPer tissue in the FABRICA. Although our resulting SSuPer tissue replicated vascularization and perfusion observed in situ, supported its own weight, and stained positively for mineral using Von Kossa staining, our in vitro results indicated that computational fluid dynamics (CFD) should be used to drive future construct design and flow application before further tissue biofabrication and perfusion. We built a CFD model of the SSuPer tissue integrated in the FABRICA and analyzed flow characteristics (net force, pressure distribution, shear stress, and oxygen distribution) through five SSuPer tissue microchannel patterns in two flow directions and at increasing flow rates. Important flow parameters include flow direction, fully developed flow, and tissue microchannel diameters matched and aligned with bioreactor flow channels. We observed that the SSuPer tissue platform is capable of providing direct perfusion to tissue constructs and proper culture conditions (oxygenation, with controllable shear and flow rates), indicating that our approach can be used to biofabricate tissue representing primary tissues and that we can model the system in silico.     

Monoclonal antibody against the poly-γ-d-glutamic acid capsule of Bacillus anthracis protects mice from enhanced lethal toxin activity due to capsule and anthrax spore challenge

Background

The poly-γ-d-glutamic acid (PGA) capsule, a major virulence factor of Bacillus anthracis, protects bacilli from immune surveillance and allows its unimpeded growth in the host. Recently, the importance of the PGA in the pathogenesis of anthrax infection has been reported. The PGA capsule is associated with lethal toxin (LT) in the blood of experimentally infected animals and enhances the cytotoxicity of LT.

Methods

To investigate the role of anti-PGA Abs on progression of anthrax infection, two mouse anti-PGA mAbs with K_d values of 0.8 μM and 2.6 μM respectively were produced and in silico three dimensional (3D) models of mAbs with their cognitive PGA antigen complex were analyzed.

Results

Anti-PGA mAbs specifically bound encapsulated B. anthracis H9401 and showed opsonophagocytosis activity against the bacteria with complement. The enhancement effect of PGA on LT-mediated cytotoxicity was confirmed ex vivo using mouse bone marrow-derived macrophages and was effectively inhibited by anti-PGA mAb. Passive immunization of mAb completely protected mice from PGA-enhanced LT toxicity and partially rescued mice from anthrax spore challenges. 3D structure models of these mAbs and PGA complex support specific interactions between CDR and cognitive PGA. These results indicate that mouse mAb against PGA capsule prevents the progress of anthrax disease not only by eliminating the vegetative form of encapsulated B. anthracis but also by inhibiting the enhanced cytotoxic activity of LT by PGA through specific binding with PGA capsule antigen.

General significance

Our results suggest a potential role for PGA antibodies in preventing and treating anthrax infection.