益肾排石中药保护高能冲击波致肾损伤的实验研究

目的：探讨益肾排石中药对高能冲击波致肾损伤的保护作用。方法：将家兔30只随机分为两组，中药组和生理盐水对照组各15只，于高能冲击波致兔肾损伤模型，测定不同时间血浆，肾组织浆浆内皮素（ET－1），超氧化物歧化酶（SOD）、丙二醛（MDA）变化及肾组织病理改变。结果：冲击波肾损伤后血浆中ET－1、血清中MDA值及组织均浆中ET－1、MDA值显著升高（P＜0．05），血浆及组织匀浆中SOD显著降低（P＜0．05）；而中药治疗组血浆中ET－1、MDA及组织均浆中ET－1、MDA峰值显著低于对照组（P＜0．05），血浆及组织匀浆中SOD值高于对照组（P＜0．05），且病理检查较对照组损伤轻。结论：益肾排石中药对高能冲击波致肾损伤具有保护作用。     

Optimization of screw fixation in rat bone with extracorporeal shock waves

Screw fixation in osteoporotic patients is becoming an increasing problem in orthopaedic surgery as deterioration of cortical and cancellous bone hamper biomechanical stability and screw fixation. This might result in delayed weight‐bearing or failure of instrumentation. We hypothesized that local peri‐operative shock wave treatment can optimize osseointegration and subsequent screw fixation. In eight female Wistar rats, two cancellous and two cortical bone screws were implanted in both femora and tibiae. Immediately after implantation, 3.000 unfocused extracorporeal shock waves (energy flux density 0.3 mJ/mm²) were applied to one side. The other side served as non‐treated internal control. Evaluation of osseointegration was performed after 4 weeks with the use of microCT scanning, histology with fluorochrome labeling, and pull‐out tests of the screws. Four weeks after extracorporeal shock wave treatment, treated legs exhibited increased bone formation and screw fixation around cortical screws as compared to the control legs. This was corroborated by an increased pull‐out of the shock wave treated cortical screws. The cancellous bone screws appeared not to be sensitive for shock wave treatment. Formation of neocortices after shock wave therapy was observed in three of eight animals. Furthermore, de novo bone formation in the bone marrow was observed in some animals. The current study showed bone formation and improved screw fixation as a result of shock wave therapy. New bone was also formed at locations remote from the screws, hence, not contributing to screw fixation. Further, research is warranted to make shock wave therapy tailor‐made for fracture fixation. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:76–84, 2018.

     

Effects of cobalt and chromium ions on glycolytic flux and the stabilization of hypoxia‐inducible factor‐1α in macrophages in vitro

Implant wear and corrosion have been associated with adverse tissue reactions that can lead to implant failure. Wear and corrosion products are therefore of great clinical concern. For example, Co²⁺ and Cr³⁺ originating from CoCrMo‐based implants have been shown to induce a proinflammatory response in macrophages in vitro. Previous studies have also shown that the polarization of macrophages by some proinflammatory stimuli is associated with a hypoxia‐inducible factor‐1α (HIF‐1α)‐dependent metabolic shift from oxidative phosphorylation (OXPHOS) towards glycolysis. However, the potential of Co²⁺ and Cr³⁺ to induce this metabolic shift, which plays a determining role in the proinflammatory response of macrophages, remains largely unexplored. We recently demonstrated that Co²⁺, but not Cr³⁺, increased oxidative stress and decreased OXPHOS in RAW 264.7 murine macrophages. In the present study, we analyzed the effects of Co²⁺ and Cr³⁺ on glycolytic flux and HIF‐1α stabilization in the same experimental model. Cells were exposed to 6 to 24 ppm Co²⁺ or 50 to 250 ppm Cr³⁺. Glycolytic flux was determined by analyzing extracellular flux and lactate production, while HIF‐1α stabilization was analyzed by immunoblotting. Results showed that Co²⁺, and to a lesser extent Cr³⁺, increased glycolytic flux; however, only Co²⁺ acted through HIF‐1α stabilization. Overall, these results, together with our previous results showing that Co²⁺ increases oxidative stress and decreases OXPHOS, suggest that Co²⁺ (but not Cr³⁺) can induce a HIF‐1α‐dependent metabolic shift from OXPHOS towards glycolysis in macrophages. This metabolic shift may play an early and pivotal role in the inflammatory response induced by Co²⁺ in the periprosthetic environment.     

Impact of dose reduction and the use of an advanced model-based iterative reconstruction algorithm on spectral performance of a dual-source CT system: A task-based image quality assessment

PurposeTo assess the impact of dose reduction and the use of an advanced modeled iterative reconstruction algorithm (ADMIRE) on image quality in low-energy monochromatic images from a dual-source dual energy computed tomography CT (DSCT) platform.Materials and methodsAcquisitions on an image-quality phantom were performed using DSCT equipment with 100/Sn150 kVp for four dose levels (CTDI_vol: 20/11/8/5mGy). Raw data were reconstructed for six energy levels (40/50/60/70/80/100 keV) using filtered back projection and two levels of ADMIRE (A3/A5). Noise power spectrum (NPS) and task-based transfer function (TTF) were calculated on virtual monoenergetic images (VMIs). Detectability index (d′) was computed to model the detection task of two enhanced iodine lesions as function of keV.ResultsNoise-magnitude was significantly reduced between 40 to 70 keV by ?56 ± 0% (SD) (range: ?56%–?55%) with FBP; ?56 ± 0% (SD) (?56%–?56%) with A3; and ?57 ± 1% (SD) (range: ?57%–?56%) with A5. The average spatial frequency of the NPS peaked at 70 keV and decreased as ADMIRE level increased. TTF values at 50% were greatest at 40 keV and shifted towards lower frequencies as the keV increased. The detectability of both lesions increased with increasing dose level and ADMIRE level. For the simulated lesion with iodine at 2 mg/mL, d’ values peaked at 70 keV for all reconstruction types, except for A3 at 20 mGy and A5 at 11 and 20 mGy, where d’ peaked at 60 keV. For the other simulated lesion, d’ values were highest at 40 keV and decreased beyond.ConclusionAt low keV on VMIs, this study confirms that iterative reconstruction reduces the noise magnitude, improves the spatial resolution and increases the detectability of enhanced iodine lesions.     

Comparison of Perfusion Quality in Hollow‐Fiber Membrane Oxygenators for Neonatal Extracorporeal Life Support

Perfusion quality is an important issue in extracorporeal life support (ECLS); without adequate perfusion of the brain and other vital organs, multiorgan dysfunction and other deficits can result. The authors tested three different pediatric oxygenators (Medos Hilite 800 LT, Medtronic Minimax Plus, and Capiox Baby RX) to determine which gives the highest quality of perfusion at flow rates of 400, 600, and 800 mL/min using human blood (36°C, 40% hematocrit) under both nonpulsatile and pulsatile flow conditions. Clinically identical equipment and a pseudo‐patient were used to mimic operating conditions during neonatal ECLS. Traditionally, the postoxygenator surplus hemodynamic energy value (SHE_post, extra energy obtained through pulsatile flow) is the one relied upon to give a qualitative determination of the amount of perfusion in the patient; the authors also examined SHE retention through the membrane, as well as the contribution of SHE_post to the postoxygenator total hemodynamic energy (THE_post). At each experimental condition, pulsatile flow outperformed nonpulsatile flow for all factors contributing to perfusion quality: the SHE_post values for pulsatile flow were 4.6–7.6 times greater than for nonpulsatile flow, while the THE_post remained nearly constant for pulsatile versus nonpulsatile flow. For both pulsatile and nonpulsatile flow, the Capiox Baby RX oxygenator was found to deliver the highest quality of perfusion, while the Minimax Plus oxygenator delivered the least perfusion. It is the authors' recommendation that the Baby RX oxygenator running under pulsatile flow conditions be used for pediatric ECLS, but further studies need to be done in order to establish its effectiveness beyond the FDA‐approved time span.     

艾司洛尔对依托咪酯诱导气管插管时脑氧供需平衡和能量代谢的影响

目的:观察艾司洛尔对依托咪酯诱导气管内插管时脑氧供需平衡和能量代谢的影响。方法:将24例择期腹部手术患者随机分为艾司洛尔(A)组和对照(B)组,每组各12例。A组全麻诱导应用依托咪酯、咪达唑仑、芬太尼和维库溴铵,并在插管前30s静注艾司洛尔1mg/kg;B组除不用艾司洛尔外,其他与A组相同。分别于全麻诱导前、气管插管后即刻采集颈内静脉和桡动脉血,检测血糖、血乳酸盐及血气,记录MAP和HR;并计算脑动-静脉血氧含量差(Da-jvO2),脑氧摄取率(CERO2),葡萄糖摄取率(GluER),脑动-静脉血乳酸盐浓度差(Da-jvLac)。结果:与诱导前比较,A组插管后即刻MAP、HR无显著变化(P0.05),SjvO2增高、Da-jvO2和CERO2降低(P均0.05);B组插管后即刻MAP、HR及SjvO2明显增高(P0.01),Da-jvO2和CERO2显著降低(P0.01)。B组插管后即刻MAP、HR及SjvO2水平明显高于A组(P0.01),而Da-jvO2和CERO2水平明显低于A组(P0.05)。两组GluER和Da-jvLac无显著变化(P0.05)。结论:麻醉诱导时给予艾司洛尔1mg/kg可减轻依托咪酯诱导气管内插管对脑氧供需平衡的影响,但不影响脑的能量代谢。     

高能震波促进缺血性坏死股骨头BMP-2的表达

[目的]观察高能震波对缺血性坏死股骨头骨形态发生蛋白2(BMP-2)表达的影响,探讨高能震波治疗股骨头缺血性坏死的作用机制.[方法]健康雄性新西兰白兔38只,3.0～4.0 kg,平均3.3 kg.联合应用甲基强的松龙和内毒素6周诱发早期股骨头缺血性坏死的动物模型.所有实验兔左后腿作为治疗侧,采用能流密度0.26 mJ/mm~2,频率1 Hz,冲击量为2 000次的高能震波治疗,右后腿作为对照侧,不予治疗.分别于治疗后24 h和第1、2、4、8、12周各取6只动物处死,取股骨头标本行实时荧光定量PCR、免疫组化染色,检测BMP-2的表达.[结果]高能震波治疗显著增加了兔股骨头骨组织中BMP-2 mRNA的表达,治疗侧股骨头BMP-2 mRNA的表达在治疗后第24 h以及第1、2、4、8周显著高于对照侧,在治疗后第1周BMP-2 mRNA的表达最高.高能震波治疗后4、8和12周,治疗侧股骨头BMP-2平均染色面积百分比显著高于对照侧(P<0.01,P<0.01和P<0.01).高能震波治疗后4、8和12周,治疗侧股骨头BMP-2平均吸光度显著高于对照侧(P<0.01,P<0.01和P<0.01).[结论]高能震波治疗能有效促进缺血性坏死股骨头BMP-2的表达,可能有助于增加股骨头的骨生成,加速股骨头坏死的修复.     

茶多酚改善大鼠缺血/再灌注心脏功能和能量代谢并抑制体外培养心肌细胞的钙内流

目的：探讨茶多酚对缺血/再灌注心脏损伤的保护作用,并研究心脏能量代谢和心肌细胞钙内流是否参与了心脏缺血/再灌注损伤的保护作用。方法在大鼠Langendorff离体心脏上实施缺血/再灌注各30 min,用一导管经压力换能器连接放大器记录心功能指标;用31P NMR技术测定心脏的能量代谢,全细胞膜片钳技术记录心肌细胞钙内流。结果与对照组比较,茶多酚（2.5 mg/L）能使缺血/再灌注心脏的心室发展压、左心室压最大收缩速率（+dp/dtmax）、左心室压最大舒张速率（-dp/dtmax）和冠脉流量显著增加（P<0.05）,并显著改善缺血/再灌注心脏的能量代谢,增加心肌ATP和PCr含量（P<0.05）。浓度为2.5和5.0 mg/L的茶多酚均能显著抑制培养心肌细胞的钙内流（P<0.01）。结论茶多酚对大鼠离体心脏缺血/再灌注损伤的保护作用可能与其改善心肌能量代谢、抑制心肌细胞钙内流的作用有关。     

多发性骨髓瘤中医病机分析及证治思路

多发性骨髓瘤(multiple myeloma,MM)是一种浆细胞恶性肿瘤,随年龄增长发病率升高,多经意义未明的单克隆免疫球蛋白血症(monoclonal gammopathy of undetermined significance, MGUS)发展而来。本文在前人经验基础上,提出了完整的肾虚血瘀证治思想;认为肾虚无制、瘀毒肆虐是MM发生的关键;提出了补肾阴、扶正气、破瘀毒、解症状基本治法,使MM恢复到MGUS状态。     

基于FRET技术MMP3生物传感器载体的构建和鉴定

目的: 探讨基质金属蛋白酶3(MMP3)生物传感器载体的构建,阐明MMP3在活细胞中表达的时空信息。方法: 构建定位于细胞膜表面的ECFP-MMP3-YPet生物传感器载体并进行鉴定;转染293T细胞24h后观察转染效率;加尿激酶型纤溶酶原激活物(uPA)刺激293T细胞,运用荧光共振能量转移(FRET)技术在共聚焦显微镜下观察MMP3生物传感器载体的荧光共振能量转移情况ECFP-MMP3-YPet biosensor。结果: 成功构建ECFP-MMP3-YPet biosensor;PCR和双酶切鉴定,MMP3-YPet约780bp,转染293T细胞后MMP3生物传感器在胞质较均匀分布,转染效率约40%。uPA刺激293T细胞后,胞质和胞核内FRET比值逐渐降低,约30min时达到最小值,随后恢复正常。结论: 基于FRET构建的MMP3生物传感器可以敏感而准确地监测活细胞中MMP3的表达情况。