二仙汤对去卵巢大鼠心肌微血管及血液流变学的影响

目的:观察去卵巢大鼠心肌微血管密度、微血管内皮细胞形态及血液流变学的变化并探讨二仙汤的干预作用。方法:选用健康10周龄雌性SPF级SD大鼠32只,随机分为假手术组、模型组、雌激素组(戊酸雌二醇,0.18 mg·kg~(-1)),二仙汤组(9 g·kg~(-1))。去卵巢后2周开始灌胃给药,1次/d,连续16周。二仙汤组及雌激素组分别给予二仙汤或戊酸雌二醇灌胃,假手术组和模型组灌胃等体积纯净水。给药16周末,无创超声心动图(UCG)检测心功能;CD34免疫荧光染色法检测心肌微血管密度;透射电镜观测心肌微血管超微结构;放射免疫分析法检测血浆雌二醇(E_2)含量;酶联免疫吸附测定(ELISA)检测血浆内皮素-1(ET-1),前列环素I_2(PGI_2),血栓素A_2(TXA_2),血管内皮生长因子(VEGF)和血管性血友病因子(vWF)水平;凝固法检测凝血四项;血液流变学检测全血黏度和血浆黏度。结果:与假手术组比较,模型组左室射血分数(EF)显著降低(P0.01),左室短轴缩短率(FS)显著降低(P0.01),左室收缩末期容积(LVVols)显著升高(P0.01);心肌微血管密度显著减少(P0.01);心肌微血管内皮细胞肿胀明显,胞浆空化;血浆E_2含量显著降低(P0.01);ET-1,VEGF,vWF含量显著升高(P0.01),前列环素I_2/血栓素A_2(PGI_2/TXA_2)显著降低(P0.01);血浆活化部分凝血酶原时间(APTT)显著降低(P0.01),纤维蛋白原(FIB)含量显著升高(P0.01);全血黏度、血浆黏度、卡松黏度显著升高(P0.01),全血高、低切指数和红细胞聚集指数明显升高(P0.05)。与模型组比较,二仙汤组大鼠EF,FS明显升高(P0.05),LVVols明显降低(P0.05);微血管密度显著增多(P0.01);心肌微血管内皮细胞水肿改善,运输小泡清晰可见;血浆E_2显著升高(P0.01);ET-1,VEGF显著降低(P0.01),PGI_2/TXA_2显著升高(P0.01);APTT显著升高(P0.01);全血黏度、全血高切相对指数、红细胞聚集指数明显降低(P0.05),卡松黏度、血浆黏度显著降低(P0.01)。结论:二仙汤增加去卵巢大鼠心肌微血管密度、保护微血管内皮细胞结构的完整性,改善其内皮分泌功能和血液流变学,保护心功能。     

Clinical effectiveness and radial artery remodeling assessment via very-high-frequency ultrasound/ultra biomicroscopy after applying slender 7Fr sheath for transradial approach in left main bifurcation disease

Abstract

Objective

To explore the clinical effect and radial remodeling of transradial slender 7?Fr sheath for left main bifurcation disease (LM bifurcation).     

Gray platelet syndrome: Management of perioperative bleeding in redo cardiac surgery

Gray platelet syndrome (GPS) is a rare (<1/1 000 000) and inherited platelet function disorder characterized by macrothrombocytopenia, α-granule deficiency, and hemorrhages. Bleeding intensity does not correlate with platelet count nor with functional test results. We hereby describe the perioperative bleeding prevention and management of a patient with GPS requiring multiple redo cardiac surgeries.     

Comparative study on the manually-controlled variable-rate versus fixed-rate infusion of norepinephrine for preventing hypotension during spinal anesthesia for cesarean delivery

Study objectivePrevious studies have shown that prophylactic norepinephrine infusion is superior to intermittent bolus administration in preventing post-spinal hypotension. Nevertheless, it is still controversial whether manually-controlled variable-rate infusion is more effective than fixed-rate infusion. The purpose of the present study was to compare the efficacy of variable-rate infusion and fixed-rate infusion of norepinephrine for prophylaxis against maternal hypotension and maintaining hemodynamic stability during spinal anesthesia for cesarean delivery to determine more effective mode for clinical practice.DesignA prospective randomized, controlled study.SettingOperating room, Women's Hospital, Zhejiang University School of Medicine.PatientsA total of 161 parturients scheduled for elective cesarean delivery with spinal anesthesia were randomized into Group F (fixed-rate infusion) and Group V (variable-rate infusion).InterventionsParturients received prophylactic norepinephrine infusion concurrent with the intrathecal injection at rate started at 0.05 μg/kg/min. In Group F, norepinephrine was administered continuously at a fixed (on-off) rate, and a bolus of norepinephrine 5 μg or 10 μg was given when systolic blood pressure (SBP) decreased by 20% or more of baseline. In Group V, manually adjusted norepinephrine infusion within the range 0–0.14 μg/kg/min, according to SBP at 1-min intervals until delivery, aim to maintain values close to the baseline.MeasurementsDuring the study period, the incidence of maternal hypotension, hemodynamic performance, the number of physician interventions, reactive hypertension, bradycardia, nausea, vomiting, norepinephrine cumulative dose (before delivery), and neonatal outcomes were recorded.Main resultsThe incidence of maternal hypotension was significantly lower in Group V than that in Group F (9% versus 30%) (P < 0.001). No significant difference was found in the serial changes in SBP and heart rate (HR) for the first 15 min. Group V showed higher frequency of physician interventions compared with the Group F (P < 0.001). The incidence of hypertension, severe hypotension, nausea, vomiting, bradycardia, norepinephrine cumulative dose, and neonatal outcome were comparable between the two groups.ConclusionWhen norepinephrine was infused at an initial dose of 0.05 μg/kg/min for preventing hypotension during spinal anesthesia for cesarean delivery, due to technical limitations of inadequate dose design in this study, neither a variable-rate infusion (need more physician intervention) nor a fixed-rate infusion regimen (experience more transient hypotension) was optimal. However, in terms of clinical importance, how to prevent the parturients from experiencing more incidence of hypotension might be a greater concern for anesthesiologists.     

口服蛋氨酸饲料致大鼠心室重塑的研究

目的:探讨口服蛋氨酸饲料致大鼠心力衰竭模型的机制，及程序性死亡因子4（PDCD4）通路在此过程中的作用。方法:5周龄健康Wistar雄性大鼠30只，适应性喂养1周后，随机分为实验组与对照组，实验组给予3%蛋氨酸饲料喂养，对照组标准饲料喂养。12周后进行血流动力学检测，采用酶联免疫法测定血清同型半胱氨酸（HCY）及N端前脑钠肽（NT-proBNP）水平，心脏彩超进行心功能评估，病理染色明确有无细胞肥大、纤维化，Western blot检测心肌组织中PDCD4蛋白的表达。结果:3%蛋氨酸饲料喂养组HCY水平较对照组升高（均P＜0.05）,心脏彩超提示3%蛋氨酸饲料喂养组大鼠左室射血分数、缩短分数、室间隔厚度显著减低（均P＜0.05），左室收缩末内径及舒张末内径较对照组显著增加（均P＜0.05），Western blot结果显示, PDCD4蛋白表达降低（P＜0.05）。结论:通过口服蛋氨酸饲料造成大鼠高HCY血症可导致大鼠出现心室重塑，并造成心功能受损，其机制可能与PDCD4信号通路的下调有关。     

Post-natal bone physiology

Post-natal bone development is characterized by substantial longitudinal bone growth and changes in skeletal size and shape. Bone is in a dynamic process of continuous remodeling which helps to regulate calcium homeostasis, repair micro-damage to bones from everyday stress, and to shape the skeleton during growth. Bone growth is regulated by systemic hormones and locally generated factors. Understanding their mechanisms of action enables us to obtain a better appreciation of the cellular and molecular basis of bone remodeling and could therefore be valuable in approaches to new therapies. This article will review molecular and cellular control of skeletal growth in the post-natal period, the physiology of each bone cell with their systemic and local regulators, as well as the physiology of bone remodeling.     

儿童埋藏式心律转复除颤器的应用进展

埋藏式心律转复除颤器(ICD)在心源性猝死中有不可替代的作用,随着ICD技术的发展,儿童ICD植入也日趋增多,但由于儿童的特殊性,儿童ICD在应用指征、器械及植入方式的选择等方面仍面临着巨大挑战。现就儿童ICD临床应用的相关问题,包括常见病种、适应证及ICD系统的临床应用进行综述。