A supercritical fluid-based coating technology. 2: Solubility considerations

Solubility measurements of candidate coating materials have been performed in supercritical (SC) CO₂ so as to select appropriate coating materials for implementation of a solvent-free coating process previously described. Solubility of lipidic compounds such as waxes (paraffin, beeswax, Carnauba wax), pure triglycerides (tricaprin, trimyristin, tripalmitin, tristearin) and mixture of glycerides and fatty acid esters (Gelucire®) in SC CO₂ were evaluated in a static mode under different temperature and pressure conditions, ranging from 13–52°C and from 50–220 bar, whether the CO₂ was in its liquid or SC state. It was shown that the compounds which are mixtures of various components give rise to a selective extraction of the lower melting point components, as evidenced from thermal analysis of soluble and insoluble fractions of the coating materials.     

Development and validation of a quantitative real time PCR assay for BK virus

Several studies have shown that BK viral load in plasma and urine are reliable markers for the detection of BK virus associated nephropathy (BKVAN) in renal transplant patients. We developed a quantitative real time PCR assay based on TaqMan technology for the measurement of BK viral load in plasma and urine. Considering the high similarity of the nucleotide sequence of the BK virus (BKV) with the JC virus (JCV), we designed this assay to specifically amplify BKV. We determined the viral DNA recovery rate on manual (QIAGEN's QIAamp DNA Blood Mini Kit) and automated (BioMerieux's NucliSENS EasyMAG) extraction methods. The comparison showed a higher viral DNA recovery rate on the automated extraction (61–76% in plasma and 52–65% in urine) as compared to the manual method (49–52% in plasma and 33–56% in urine). Quantitation of the viral load was performed using an external standard curve that was constructed with serial dilution of a plasmid containing the full length of the BKV genome. Commercially available quantitative BKV standards showed good correlation with the plasmid standard. The reproducibility of the assay was determined based on the Ct values of the amplified products as well as in BK copies per milliliter of sample. This assay is linear over a 7 log range (10 to 1 × 10⁷ copies per reaction), no cross-reactivity was detected with the closest-related polyomavirus JCV, as well as other viruses that may be found in immunocompromised patients, and human genomic DNA. The limit of detection of the assay is 300 copies per milliliter in both plasma and urine and the limit of quantitation is 1000 copies per milliliter using the NATtrol BK Virus Linearity Panel (ZeptoMetrix). This real time PCR assay provides a reliable and sensitive method for the quantitation of BKV in plasma and urine samples.     

侧柏总黄酮的分离纯化及对5-脂氧合酶的抑制作用

 目的从侧柏叶中分离纯化活性成分总黄酮并探讨其对5-脂氧合酶的抑制作用。方法石油醚加热回流除去大部分叶绿素等脂溶性杂质,再用体积分数为50%乙醇加热回流提取;提取液浓缩去除乙醇后用乙酸乙酯提取,减压浓缩得粗黄酮;粗黄酮过聚酰胺色谱柱,用体积分数为70%的甲醇洗脱,浓缩得总黄酮;高效液相色谱法测定大鼠中性白细胞5-脂氧合酶的产物5-羟廿碳四烯酸,Fura-2/AM荧光技术测定细胞内游离钙浓度。结果用芦丁作参照品,测得分离的产物总黄酮含量为93%,总黄酮对5-脂氧合酶抑制的IC₅₀为22.2;25～125 mg·L^-1的总黄酮对fMLP诱导的细胞内游离Ca²⁺水平增高抑制率为15.2%～35.9%。结论该方法较简单,分离的总黄酮纯度高,是一种可行的总黄酮提取方法;侧柏总黄酮对5-脂氧合酶的活性有较强的抑制作用,抑制细胞内游离Ca²⁺水平增高可能是抑制5-脂氧合酶的作用机制之一。     

Smashing Tissue Extraction and HPLC Determination of Active Saponins from Different Parts of Panax notoginseng

Objective To optimize the extraction technology used for extracting active saponins from the roots,fibrous roots,basal part of stems,root verrucae,fruits,flowers,stems,and leaves of Panax notoginseng based on the contents of ginsengsides Rg1,Rb1,and notoginsengside R1 as evaluation indexes.Methods Different parts of P.notoginseng were extracted by smashing tissue extraction(STE),ultrasound extraction,and reflux extraction.The contents of ginsengsides Rg1,Rb1,and notoginsengside R1 in 24 kinds of extracts were determined by HPLC-UV.Hypersil C18 column(200 mm × 4.6 mm,5 μm) and acetonitrile-warter(20:80 for 30 min→45:55 for 18 min→70:30 for 2 min→80:20 for 10 min→100:0) were used;UV detector was set at 203 nm;The flow rate was set at 1.0 mL/min.Results STE was the most efficient technology with the highest yield of active saponins among the three tested extraction technologies.Conclusion STE is a fast,effective,and economical method to extract the active saponins from different parts of P.notoginseng.It could significantly shorten the extraction time and simplify the determination of the pre-processing work on identifying P.notoginseng.Such quick and effective extraction provides a powerful tool for analyzing P.notoginseng in the future.     

阳离子交换-高效液相色谱-电化学法测定人血浆中儿茶酚胺的浓度

目的:采用弱阳离子固相萃取小柱(WCX-SPE)优化人血浆儿茶酚胺检测实验条件,以减少血浆用量,提高实验稳定性,建立操作简单、可靠的人血浆儿茶酚胺浓度检测方法。方法:采用waters WCX固相萃取小柱提取血浆中儿茶酚胺,采用高效液相色谱-电化学检测法测定儿茶酚胺,并对其线性范围、方法回收率、提取回收率、日间日内精密度及稳定性进行考察。结果:去甲肾上腺素(NE)在50~2 000 pg·ml^-1(n=6,r=0.998 5),肾上腺素(E)在50~2 000 pg·ml^-1(n=6,r=0.999 3)浓度范围内线性关系良好,最低检测限分别为25,50 pg·ml^-1 (S/N≥3),NE、E样品的平均提取回收率分别为89.6%、91.5%,平均方法回收率分别为100.6%,99.4%,平均日间RSD分别为5.1%,4.3%,平均日内RSD分别为3.9%,3.6%。结论:采用WCX固相萃取小柱提取血浆中儿茶酚胺灵敏度高,操作简便,结果准确可靠,适合于临床诊疗需要。     

Balloon dilation of intrahepatic biliary strictures for percutaneous extraction of residual intrahepatic stones

Intrahepatic ductal strictures in cholangiohepatitis present an obstacle to successful removal of retained ductal stones via T-tube tracts. We studied the effectiveness of stricture dilatation for stone removal. Fifteen patients with intrahepatic gallstones retained behind strictures underwent balloon dilatation of their strictures to allow stone extraction. All had prior surgical T-tube placement allowing percutaneous access. Balloon dilatation was successful in reducing or eliminating strictures in 86.7% (13 of 15 patients), and complete stone extraction after the successful dilatation was possible in 76.9% (10 of 13 patients). The reasons for failure were impacted stones and acute ductal angulation which prevented passage of catheters. It is concluded that balloon dilatation of intrahepatic biliary strictures is an effective adjunct for extraction of intrahepatic biliary calculi associated with recurrent pyogenic cholangiohepatitis.     

Complications of renal extracorporeal shock wave lithotripsy reviewed

Renal extracorporeal shock wave lithotripsy (ESWL) is a noninvasive and effective method for the treatment of a variety of urinary tract calculi with significantly lower morbidity than both surgical procedures for stone removal (pyelolithotomy/ureterolithotomy) and percutaneous nephrostolithotomy. Though significant, severe complications are rare, ESWL therapy can result in a wide spectrum of tissue injury. This article serves to review the currently known complications of ESWL, which radiologists may encounter, providing an understanding of the potential effects of shock waves on body organs and the resultant functional and morphologic changes that may result.     

两种方法在拔除下颌阻生第三磨牙中的疗效比较

目的:观察和比较两种拔除下颌阻生第三磨牙的临床疗效。方法:门诊200例下颌阻生第三磨牙随机分为两组,各100颗。分别采用传统锤凿去骨法和涡轮机去骨法拔除,记录手术时间、术后疼痛、张口受限等情况并进行统计学分析。结果:两种手术方法在手术时间、术后疼痛、张口受限、肿胀程度等方面有统计学差异(P<0.05),传统锤凿去骨组出现干槽症与下唇麻木分别为5例和1例,涡轮机去骨组分别为1例和0例,组间比较差异无统计学意义(P>0.05)。结论:与传统锤凿去骨法相比,采用涡轮机去骨法拔除下颌阻生第三磨牙手术时间短,术后并发症较少,值得临床推广。     

无细胞的异体神经修复鼠坐骨神经缺损

目的 通过化学萃取同种异体神经,去除髓鞘和雪旺细胞,形成无细胞基膜管后桥接鼠坐骨神经缺损,研究神经再生效果。方法 正常鼠坐骨神经用非变性生物剂处理后得到无细胞的基膜管,桥接鼠坐骨神经20mm缺损。实验分3组:无细胞基膜管移植组(A组),自体神经移植组(B组)和异体神经移植组(C组)。术后进行肌电图、光镜、电镜及图象分析仪检查。结果 A组再生神经有大量轴突通过移植体,术后2个月电生理检测再生神经的潜伏期及波幅低于B组(P<0.05),术后3个月2组差异无显著意义。髓鞘厚度在术后3个月时亦低于B组,差异有显著意义(P<0.05)。轴突直径及数目两组无差异。C组因无神经再生,结果无法测量。结论 这种无细胞基膜管移植体能支持轴突的生长和雪旺细胞的迁移,是一种良好的神经移植替代材料。     

水冲核小切口老年性白内障摘除术临床观察98例

目的 探讨水冲核技术在老年性白内障摘除术中的临床治疗效果. 方法 回顾性分析2008年6月～2011年6月间我院收治的98例(98眼)老年性白内障患者,根据其手术方式分为两组,观察组58例,采取水冲核非超声乳化手术;对照组40例,采用传统手法小切口非超声乳化手术,分析其治疗过程及预后. 结果 98例(98眼)术后视力均有不同程度提高,术后3个月内的最佳裸眼视力0.5以上者,观察组47例(81.0％),对照组27例(67.5％),P＜0.05,差异有统计学意义.最佳裸眼视力1.0以上者,观察组12例(20.7％),对照组3例(7.5％),P＜0.05,差异有统计学意义.术后散光观察组平均为(1.04±0.10)D,对照组平均为(1.21±0.11)D,术后观察组和对照组的角膜平均散光度数的比较,P＜0.05,差异有统计学意义.观察组的角膜平均散光度数手术前后差异无显著性;对照组的角膜平均散光度数手术前后差异有统计学意义. 结论 水冲核白内障手术对角膜内皮的损伤较小、恢复较快,优于常规法,值得在临床中推广.