Factors affecting protein release from alginate-chitosan coacervate microcapsules during production and gastric/intestinal simulation.

A series of experiments was performed to evaluate the influence of a number of physico-chemical factors on the diffusion of a model protein, bovine serum albumin (BSA), from dried chitosan-coated alginate microcapsules. Diffusion of BSA was quantified during the microcapsule manufacture processes (gelation, washing, rinsing) and during incubation in conditions simulating the pH encountered during the gastric (0.1 N HCl; pH 1.5) and intestinal (200 mM Tris-HCl; pH 7.5) phases of digestion. Factors tested included alginate and chitosan concentration, calcium chloride (CaCl2) concentration in the gelation medium, loading rate, chitosan molecular mass and pH of the gelation medium. Microcapsule size and gelation time were altered in order to determine their effects on protein retention. Alginate and chitosan concentration significantly influenced BSA retention during microcapsule manufacture and acid incubation, as did calcium chloride concentration in the gelation medium (P<0.05). BSA retention during manufacture was not significantly altered by protein loading rate or pH of the encapsulation medium, however, protein retention during acid incubation decreased significantly with increasing protein loading rate and encapsulation medium pH (P<0.05). Microcapsules that were washed with acetone following manufacture demonstrated significantly increased protein retention during acid incubation (P<0.05). In microcapsules that had been acetone-dried to a point whereby their mass was reduced to 10% of that immediately following encapsulation, protein retention was over 80% following 24-h acid incubation vs. only 20% protein retention from non acetone-dried microcapsules. The presence of calcium in the neutral buffer medium significantly reduced BSA diffusion in a concentration-dependent manner (P<0.05).     

超选择性肾动脉栓塞在医源性肾出血中的应用

目的 探讨超选择性肾动脉栓塞对治疗医源性肾出血的临床应用价值.方法 对杭州师范大学附属医院2005年11月至2010年11月期间19例经保守治疗失败的医源性肾动脉损伤出血患者进行诊断性肾动脉造影,确定出血部位及性质,再行超选择性插管至出血动脉,采用弹簧圈或者弹簧圈联合明胶海绵进行栓塞治疗.结果 19例患者经DSA肾动脉造影证实:出血部位均为肾段及段以下动脉分支,其中肾段动脉9例,叶间动脉6例,弓状动脉4例.单纯肾段动脉损伤出血2例,伴假性动脉瘤9例,伴动静脉瘘5例,伴假性动脉瘤合并动静脉瘘3例.本组中2例假性动脉瘤患者采用微弹簧圈栓塞后,发现仍有少量出血,采用明胶海绵颗粒补充栓塞,其余17例患者均单独采用弹簧圈栓塞.19例患者均一次性栓塞成功止血,随访无l例复发.结论 超选择性肾动脉栓塞技术是治疗医源性肾损伤出血的一种安全、有效的方法.     

Percutaneous transcatheter super-selective renal arterial embolization with N-butyl cyanoacrylate for iatrogenic renal hemorrhage

BackgroundTo evaluate the safety and efficacy of percutaneous transcatheter super-selective renal arterial embolization (SRAE) with N-butyl cyanoacrylate (NBCA) for iatrogenic renal hemorrhage.MethodsBetween January 2014 and December 2019, 45 patients (including 18 patients with coagulopathy), who underwent percutaneous transcatheter SRAE with NBCA for iatrogenic renal hemorrhage at our institution, were retrospectively reviewed. The technical success rate, clinical success rate, and embolization-related complications were analyzed. The values of estimated glomerular filtration rate (eGFR), serum creatinine (sCr), and serum urea (sUr) were analyzed at the time of pre-SRAE, post-SRAE, and last follow-up to evaluate the effects of NBCA-based SRAE on renal function.ResultsDiagnostic renal arteriography revealed contrast extravasation in 18 patients and pseudoaneurysms in 27 patients. NBCA mixed with iodized oil in a 1:2–1:4 ratio was the sole embolic agent. No procedure-related mortality or major complications occurred. The technical and clinical success rates were both 100%. The values of eGFR, sCr and sUr were not found to be significantly different between pre-SRAE, post-SRAE and last follow-up (eGFR: 91.52 ​± ​21.17 vs. 90.98 ​± ​22.11 vs. 92.14 ​± ​23.51 ​mL/min/1.73 ​m², p ​= ​0.729; sCr: 74.73 ​± ​11.08 vs. 75.27 ​± ​12.43 vs. 73.95 ​± ​10.14 ​μmol/L, p ​= ​0.543; sUr: 5.69 ​± ​0.84 vs. 5.71 ​± ​0.96 vs. 5.70 ​± ​0.79, p ​= ​0.515, respectively).ConclusionsPercutaneous transcatheter SRAE with NBCA is a safe and effective treatment modality for iatrogenic renal hemorrhage with no deterioration of renal function.     

超选择性肾动脉栓塞治疗肾动静脉畸形所致血尿

评价经动脉栓塞治疗静脉曲张型肾动静畸形(rAVM)所致血尿的安全性和疗效。方法:回顾性分析10例因肉眼血尿为主要表现的rAVM患者,随访观察行微钢圈栓塞治疗的效果及安全性。结果:10例经DSA检查后均诊断为静脉曲张型rAVM,均获得成功栓塞,术后15~48 h(平均28 h)血尿消失,随访12~36月未见血尿复发,无严重并发症。结论:经动脉微钢圈栓塞治疗静脉曲张型rAVM所致的血尿安全、有效。     

能量多普勒超声对土贝母皂甙微囊栓塞治疗兔肾VX2移植癌的疗效观察

目的:利用能量多普勒超声评价土贝母皂甙微囊经肾动脉灌注对兔VX2移植性肾癌模型的治疗作用。方法:复制40只兔VX2移植性肾癌模型,随机分为对照组、土贝母组、空白微囊组、土贝母皂甙微囊组各10只,经肾动脉分别注入生理盐水3ml、土贝母注射液0.1mg/kg、空白微囊5.1mg/kg、土贝母皂甙微囊5.1mg/kg。1周后对各组兔肿瘤生长情况及血流的变化进行观察。结果:栓塞治疗后土贝母皂甙微囊组兔肾癌的生长受到明显抑制,肿块内及其周边出现强回声光团,低回声肿块回声增强或变成强弱不等回声。术前土贝母皂甙微囊组10个肿块内均可测及血流信号,术后8个肿块血流信号完全消失,2个肿块血流信号明显减少。结论:能量多普勒超声可对土贝母皂甙微囊栓塞治疗兔肾VX2移植癌疗效评价提供准确、客观的依据。     

PCNL术后肾出血介入止血的临床研究

目的研究PCNL术后肾出血的介入止血方法及效果。方法12例PCNL术后。肾出血患者均采用Seldinger法穿刺右侧股动脉，超选择插管至肾动脉或。肾段动脉行DSA检查，进一步超选插管至肾动脉出血口，以明胶海绵颗粒（条）进行栓塞，必要时加PVA或弹簧圈等栓塞材料栓塞止血。结果介入方法栓塞治疗PCNL术后肾出血12例，Hb和RBC递增，4～7天痊愈出院。结论介入方法为PCNL术后。肾出血止血安全有效的方法。     

肾活检后肾出血行肾动脉造影及栓塞治疗的临床应用价值

目的探讨肾动脉造影和栓塞治疗经保守治疗无效的创伤性肾出血的临床价值。方法对9例肾活检后肾出血病例行超选择血管造影和栓塞治疗,栓塞材料选用明胶海绵和弹簧圈。结果超选择性肾动脉造影明确了出血的部位、程度及相关血管的情况,为栓塞治疗提供了依据,9例肾出血患者栓塞后出血完全停止,并保留了患肾的部分组织和功能。结论选择性肾动脉造影与栓塞是肾活检后肾出血可靠的诊断方法,也是安全、有效的止血手段,并对保留患肾功能有重要意义。     

The effects of intrarenal infusion of recombinant human erythropoietin on mean arterial pressure and renal hemodynamics in anesthetized rabbits.

The effects of recombinant human erythropoietin (rHuEPO) on mean arterial pressure (MAP) and renal hemodynamics were studied in anesthetized rabbits without renal failure. Intrarenal infusion of rHuEPO at a rate of 100 U/min for 30 min resulted in no change in MAP, renal blood flow, or renal vascular resistance. rHuEPO also produced no significant change in glomerular filtration rate filtration fraction, or arterial hematocrit. These results demonstrate that rHuEPO has no direct effects on MAP or renal hemodynamics in anesthetized rabbits without renal failure.     

NBCA胶经导管栓塞治疗肾动脉出血的围手术期护理

目的:探讨NBCA胶经导管栓塞治疗肾动脉出血的围手术期护理方法。方法:选择2010年1月~2013年10月应用NBCA胶经导管栓塞治疗肾动脉出血患者23例,精心做好术前、术中、术后护理。结果:23例患者均成功施行经动脉栓塞术,术后造影显示异常表现消失。术后出血症状消失,无器官坏死并发症。结论:对于各种原因所致的肾出血性病变,经导管栓塞治疗中单独应用NBCA或联合应用其他栓塞材料是安全有效的。做好围术期护理是确保介入治疗成功的关键。     

Transcatheter arterial embolization in blunt hepatic trauma

Patients with blunt hepatic injury can safely be managed nonoperatively if they show hemodynamic stability. Transcatheter arterial embolization (TAE) is a useful adjunct in the treatment of patients who show evidence of continued hemorrhage or who have pooling of contrast material on computed tomography (CT). In these patients, TAE may reduce transfusion requirements and allow healing of the injury without operation. Complications are uncommon and are usually managed nonoperatively.     

Effect of yohimbine on renal sympathetic nerve activity and renal norepinephrine spillover in anesthetized rabbits.

The function of presynaptic alpha-2 adrenergic autoinhibition of norepinephrine release was studied in anesthetized rabbits (alfadolone + alfaxalone) with uninterrupted sympathetic impulse traffic. The animals received a tracer infusion of [3H]norepinephrine i.v. Arterial and renal venous concentrations of endogenous norepinephrine and [3H]norepinephrine, the firing rate of the renal sympathetic nerves and renal blood flow were determined. The results were used to calculate the renal fractional [3H]norepinephrine extraction, the renal removal and spillover of norepinephrine, the total body [3H]norepinephrine clearance and total body norepinephrine spillover. Sodium nitroprusside (10-80 micrograms kg-1 min-1 i.v.), which was infused to modulate sympathetic activity through the baroreceptors, caused hypotension and increased the renal sympathetic firing rate and the renal as well as total body norepinephrine spillover. Increases of total body norepinephrine spillover were much higher than increases of renal spillover. Yohimbine (1 mg kg-1 + 0.2 mg kg-1 hr-1 i.v.) caused slight central sympathoexcitation. In addition, it enhanced the renal and total body spillover of norepinephrine at any given firing rate of the renal sympathetic nerves. The distinguishing feature of this study is the measurement of sympathetic firing rate and norepinephrine spillover in one and the same organ, the kidney. The results demonstrate that the alpha-2 adrenergic autoinhibition of norepinephrine release normally operates in the kidney with intact sympathetic impulse traffic. They also suggest its operation in other peripheral sympathetically innervated tissues.     

动脉栓塞治疗兔肝VX2肿瘤疗效的超声观察

目的探讨二维超声、能量多普勒超声造影及免疫组化方法观察肝动脉三氧化二砷(As2O3)碘油栓塞对兔肝移植瘤生长、血管形成的影响。方法32只家兔肝内肿瘤种植后2周,随机分为4组(每组8只):生理盐水灌注组、As2O3灌注组、单纯碘油栓塞组、As2O3碘油栓塞组,As2O3的用量为2 mg/kg。治疗后1周,超声观察肿瘤大小,计算肿瘤生长率,能量多普勒超声造影监测肿瘤内血流,根据造影前后血流的丰富程度计算肿瘤内血管平均密度(MCVD)。病理切片观察肿瘤的坏死面积,计算坏死率。免疫组化方法测定肿瘤区的微血管密度(MVD)。结果经肝动脉治疗后1周,各栓塞治疗组肿瘤生长受到明显抑制,与非栓塞组间差异具有显著性意义(P<0.05)。As2O3碘油栓塞组肿瘤坏死率大于其他组(P<0.05)。造影前后超声显示栓塞组肿瘤区血流较未栓塞组明显减少(P<0.05),造影前栓塞组间血流显示差异无显著性意义(P>0.05),造影后As2O3碘油栓塞组残余肿瘤区血流低于单纯碘油栓塞组(P<0.05)。单纯碘油栓塞后,残余肿瘤区的MVD略有升高(23.4±4.7),与生理盐水对照组MVD(21.8±6.3)相比,差异无显著性意义(P>0.05)。As2O3碘油栓塞组残余瘤区的MVD减低,为15.1±3.2(P<0.05)。结论As2O3碘油栓塞可抑制肿瘤生长,增加肿瘤的坏死率,抑制肿瘤血管新生。能量多普勒超声造影有利于发现栓塞后残余肿瘤血流。     

Effect of guancydine on systemic and renal hemodynamics in arterial hypertension.

The effect of guancydine (1-cyano-3-tert-amylguanidine) on systemic and renal hemodynamics was studied in nine patients with arterial hypertension. Antihypertensive drugs were withheld for 15 days before beginning the investigation. Average sodium intake was 105 meq/24 hours in some patients and 25 meq/24 hours in others. Patients received placebo during a control period that averaged 14 days. Guancydine was given for 7 to 18 days at an average dose of 21 mg/kg of body weight. Although mean arterial blood pressure decreased significantly in all patients, it reached normal levels in only two. There was no change in cardiac output. Glomerular filtration rate and renal plasma flow remained unchanged, whereas urinary sodium excretion diminished, suggesting an activation of the renin-angiotensin-aldosterone system. A substantial gain in body weight was noted. Nausea, vomiting, constipation, somnolence, restlessness, mental confusion, asthenia, and urine retention were observed. The anti-angiotensin effect of guancydine that has been described in animals was not observed.     

山莨菪碱白蛋白微球与明胶海绵颗粒行子宫动脉栓塞的比较

背景:子宫动脉栓塞治疗子宫肌瘤常出现腹部痉挛性疼痛,影响了这一技术的开展.目前常用栓塞剂有聚乙烯醇、明胶海绵、真丝线段、钢圈等.目的:以明胶海绵为对照,观察山莨菪碱白蛋白微球子宫动脉栓塞的效果及对子宫收缩的影响.设计、时间及地点:自身交叉对照实验,于1999-1012001-05在解放军总医院第二附属医院实验室完成.材料:选用月龄12～18个月雌性杂种犬10只.采用加热固化法制备山莨菪碱微球.将实验犬按随机数字表法分为2组,先行明胶海绵栓塞组和先行山莨菪碱微球栓寒组,每组5只.方法:各实验犬栓塞前肌注宫缩素,宫腔造影观察并记录子宫痉挛频率,作为子宫收缩的参照标准.先行明胶海绵栓塞组先用明胶海绵颗粒为栓塞剂,行一侧髂内动脉造影及栓塞,15 d后采用山莨菪碱微球行选择性对侧髂内动脉栓塞.15 d后切除子宫观察大体和镜下病理改变.先行山莨菪碱微球栓塞组操作同上,只是一侧髂内动脉先用山莨菪碱微球栓塞,另一侧后用明胶海绵颗粒栓塞.主要观察指标:每次栓寒后1,3,24h造影观察动脉栓塞情况及宫缩情况;病理观察子宫组织坏死情况和范围.结果:10只实验犬肌注宫缩素后8只出现宫缩.先行明胶海绵栓塞组实验犬5只,明胶海绵颗粒子宫动脉栓塞后4只出现宫缩,动脉造影显示山莨菪碱白蛋白微球具有栓塞作用,栓塞后实验犬均未出现宫缩;先行山茛菪碱微球栓塞组实验犬5只,山茛菪碱白蛋白微球子宫动脉栓塞后实验犬均未出现宫缩,明胶海绵颗粒子宫动脉栓塞后5只出现宫缩.子宫病理观察大体标本均未见明显坏死,镜下见小动脉内有微球栓塞及血栓形成,子宫内膜坏死.结论:明胶海绵子宫动脉拴塞可引起较为强烈的子宫痉挛,山茛菪碱白蛋白微球可缓解动脉栓塞所致剧烈宫缩.     

选择性子宫动脉栓塞术治疗子宫肌瘤的探讨

目的评价选择性子宫动脉栓塞术治疗子宫肌瘤的临床疗效及应用价值。方法19例子宫肌瘤患者均采用经右侧股动脉穿刺双侧子宫动脉超选择性插管,使用聚乙醇＋明胶海绵颗粒栓塞双侧子宫动脉,阻塞肌瘤血供。结果全部病例随访3～24个月,8例肌瘤体积缩小大于50％,9例肌瘤体积缩小20％-50％,月经量和月经周期恢复正常,1例缩小〈20％,临床症状明显改善,1例无明显变化。治疗后3个月18例患者血红蛋白升至105g/L以上。无1例严重并发症发生。结论选择性子宫动脉栓塞术治疗子宫肌瘤是一种安全、简便、创伤小、疗效高的治疗方法,具有较高的临床应用价值。     

阿霉素热碘油栓塞对兔肝VX2肿瘤的血流动力学影响

目的利用多普勒超声研究阿霉素热碘油栓塞治疗后兔肝VX2肿瘤及肝脏的血流动力学变化.方法 30只荷瘤兔,随机分为3组,分别采用37℃生理盐水、37℃阿霉素碘油及60℃阿霉素热碘油经兔肝动脉灌注治疗,1周后多普勒超声观察肿瘤血供及肝动脉、门静脉血流动力学变化,检测结果与治疗前相应血管的多普勒参数进行比较.肝动脉及肿瘤血管造影结果作为金标准.结果阿霉素热碘油灌注栓塞后肝动脉血流速度明显降低(P<0.05),阻力指数增大(P<0.05),门静脉血流速度及内径均无明显变化(P>0.05);治疗前,所有病灶能量及彩色多普勒均可检测出瘤内及瘤周较丰富血流信号,治疗后显示阿霉素热碘油组瘤内及瘤周血流信号均明显减弱,部分消失.结论阿霉素热碘油栓塞可更有效地阻断兔肝VX2肿瘤供血,多普勒超声可显示该血流的变化,便于对阿霉素热碘油栓塞治疗肝肿瘤的疗效进行及时评价.