SMILE术中角膜帽下地塞米松平衡液冲洗与否的早期临床观察

目的观察飞秒激光小切口角膜基质透镜取出术(SMILE)中角膜帽下地塞米松平衡液冲洗与否对术后视觉质量及角膜组织结构形态的影响。方法选择拟进行双眼SMILE手术的24例(48眼)纳入研究,每例患者随机选取一眼透镜取出后,行地塞米松平衡液冲洗角膜帽下基质腔隙(实验组),对侧眼不冲洗(对照组)。分别于术后第1天、第7天及1个月对比观察两组的裸眼视力、屈光状态、角膜中央厚度(CCT)、眼压(NCT);同时利用共焦显微镜及前段光学相干断层扫描(OCT)检查对比观察两组角膜上皮细胞、神经纤维、基质细胞、内皮细胞形态结构。采用配对t检验比较两组的裸眼视力、屈光状态等各指标有无差异。结果术后第1天、第7天及1个月两组间裸眼视力比较:实验组为4.99±0.07、5.06±0.08、5.05±0.06;对照组为5.01±0.07、5.05±0.08、5.06±0.09;3个时间点两组间裸眼视力均无统计学差异(P均>0.05);术后第1天、第7天及1个月的屈光度(SE,D):实验组为0.03±0.49、0.1±0.37、0.02±0.4;对照组为0.09±0.54、0.19±0.48、0±0.52,3个时间点两组间SE比较均无统计学差异(P均>0.05)。共焦镜检查不同时间点比较:角膜上皮层细胞密度[术前(4578.73±268.40,4539.57±329.25)个/mm^2,术后第1天(4565.21±247.31,4627.23±271.03)个/mm^2,术后第7天(4640.01±246.79,4517.71±281.43)个/mm^2];角膜内皮细胞密度[术前(2541.50±259.59,2443.52±305.58)个/mm^2,术后第1天(2387.01±248.55,2495.27±238.52)个/mm^2,术后第7天(2484.49±223.71,2482.53±323.82)个/mm^2],术前术后两组间均无统计学差异(P>0.05);角膜上皮下神经纤维丛术前术后两组间比较无明显变化;切削界面高反光物两组间比较没有明显差异;角膜前基质细胞密度[术前(789.51±67.17,802.03±67.94)个/mm^2,术后第1天(889.37±60.62,912.27±95.87)个/mm^2,术后第7天(796.67±75.03,818.39±59.65)个/mm^2]在术后第1天、第7天较术前均有增加,但两组之间没有统计学差异(P>0.05),术后1 d两组前基质细胞较术前增加,有统计学差异(P<0.05);角膜后基质细胞术后各时间点两组间比较无统计学差异(P>0.05)。角膜OCT在术后1 d、7 d两组在角膜帽下均未出现明显层间间隙和积液,两组间角膜中央厚度无统计学差异(P>0.05)。结论SMILE术中地塞米松平衡液角膜帽下冲洗对术后裸眼视力、屈光度及角膜组织结构形态无明显影响。     

Troubled-Cell Indicator Based on Mean Value Property for Hybrid WENO Schemes

In this paper, we introduce a new type of troubled-cell indicator to improve hybrid weighted essentially non-oscillatory (WENO) schemes for solving the hyperbolic conservation laws. The hybrid WENO schemes selectively adopt the high-order linear upwind scheme or the WENO scheme to avoid the local characteristic decompositions and calculations of the nonlinear weights in smooth regions. Therefore, they can reduce computational cost while maintaining non-oscillatory properties in non-smooth regions. Reliable troubled-cell indicators are essential for efficient hybrid WENO methods. Most of troubled-cell indicators require proper parameters to detect discontinuities precisely, but it is very difficult to determine the parameters automatically. We develop a new troubled-cell indicator derived from the mean value theorem that does not require any variable parameters. Additionally, we investigate the characteristics of indicator variable; one of the conserved properties or the entropy is considered as indicator variable. Detailed numerical tests for 1D and 2D Euler equations are conducted to demonstrate the performance of the proposed indicator. The results with the proposed troubled-cell indicator are in good agreement with pure WENO schemes. Also the new indicator has advantages in the computational cost compared with the other indicators.     

环孢素A对积水肾脏急性压力灌注损伤的保护

目的 在不同程度肾脏积水的前提下,观察线粒体渗透性转换孔(MPTP)抑制剂环孢素A(CsA)对于急性压力灌注所致损伤的保护作用.方法 健康新西兰大白兔20只,随机分为轻度积水组(M组,n=10)和重度积水组(S组,n=10),肾脏轻度积水及重度积水模型采用输尿管套扎法构建.M组及S组分为M1、M2、S1、S24个亚组,分别予以60、100、20、60 mmHg(1mmHg=0.133 kPa)压力灌注.灌注前M组及S组均给予CsA灌胃1周.灌注后48 h取标本,检测标本中超氧化物歧化酶(SOD)及丙二醛(MDA)的含量,JC-1染色检测线粒体膜电位(MMP)的变化.结果 M1、M2、S1、S2各组SOD活力分别为(30.11±2.23)、(28.41 ±2.26)、(44.82±6.61)、(40.31±5.21) U/mg,M1与M2之间SOD活力差异无统计学意义(P＞0.05),S1与S2之间SOD活力差异无统计学意义(P＞0.05);MDA的含量分别为(0.61 ±0.17)、(0.60±0.15)、(0.95 ±0.26)、(0.80±0.32) nmol/mg,M1与M2之间MDA含量差异无统计学意义(P＞0.05),S1与S2之间MDA含量差异无统计学意义(P＞0.05).JC-1染色橙红色阳性细胞百分比分别为(67.16±9.47)％、(60.75±11.89)％、(41.08 ±4.50)％、(42.36 ±3.44)％.M1与M2比较,S1与S2比较,阳性细胞百分比差异均无统计学意义(P＞0.05).结论 CsA对于积水肾脏因急性压力灌注所致的损伤有一定的保护作用.在经皮肾镜及输尿管镜治疗结石前给予MPTP抑制剂可有效减轻压力灌注所致损伤.     

Qualitative analysis of the removal of the smear layer in the apical third of curved roots: conventional irrigation versus activation systems

Introduction

The aim of this study was to evaluate the effectiveness of different irrigant agitation techniques on smear layer removal in curved root canals.

Methods

Mesiobuccal canals of 62 extracted lower molars with a curvature of 33 degrees were used and instrumented up to ProTaper F2. The samples were divided into 3 experimental groups according to the final irrigation: conventional irrigation, ultrasonic irrigation, and sonic irrigation by using the EndoActivator system. The control group was composed of 2 specimens without any final irrigation. In all of the experimental groups, 5 mL of 17% ethylenediaminetetraacetic acid was used for 1 minute, and 5 mL of 2.5% NaOCl was used for 30 seconds. The analysis of the apical region was performed via scanning electron microscopy by 3 examiners. The data were submitted to the Kruskal-Wallis and Dunn tests (P < .05).

Results

The activation systems removed significantly more smear layer than did conventional irrigation.

Conclusions

Sonic and ultrasonic irrigation resulted in better removal of the smear layer in the apical third of curved root canals than did conventional irrigation.     

An Explicit MUSCL Scheme on Staggered Grids with Kinetic-Like Fluxes for the Barotropic and Full Euler System

We present a second order scheme for the barotropic and full Euler equations. The scheme works on staggered grids, with numerical unknowns stored at dual locations, while the numerical fluxes are derived in the spirit of kinetic schemes. We identify stability conditions ensuring the positivity of the discrete density and energy. We illustrate the ability of the scheme to capture the structure of complex flows with 1D and 2D simulations on MAC grids.     

Tissue Dissolution by a Novel Multisonic Ultracleaning System and Sodium Hypochlorite

Introduction

This study aimed to evaluate the effectiveness of a novel Multisonic Ultracleaning System (Sonendo Inc, Laguna Hills, CA) in tissue dissolution in comparison with conventional irrigation devices.

Methods

Pieces of bovine muscle tissue (68 ± 2 mg) were placed in 0.7-mL test tubes (height: 23.60 mm, inner diameter: 6.00 mm, outer diameter: 7.75 mm) and exposed to 5 minutes of irrigation by different devices. Endodontic devices included the Multisonic Ultracleaning System, the Piezon Master 700 (EMS, Dallas, TX) ultrasonic system with agitation, the EndoVac negative-pressure irrigation system (SybronEndo, Orange, CA), and a conventional positive-pressure 27-G irrigation needle at a flow rate of 10 mL/min. The systems were tested with 0.5%, 3%, and 6% sodium hypochlorite (NaOCl) at room temperature (21°C) as well as 40°C. Irrigation with sterile water was used as a control. The mass of tissue specimens was measured and recorded before and after the use of each device, and if the specimen was completely dissolved visually within 5 minutes, the dissolution time was recorded. The rate of tissue dissolution (%/s) was then calculated.

Results

The Multisonic Ultracleaning System had the fastest rate of tissue dissolution (P < .05), at 1.0% ± 0.1% per second using 0.5% NaOCl, 2.3% ± 0.9% per second using 3% NaOCl, and 2.9% ± 0.7% per second using 6% NaOCl. This tissue dissolution rate was more than 8 times greater than the second fastest device tested (P < .01), the Piezon Master 700 ultrasonic system, which resulted in a tissue dissolution rate of 0.328% ± 0.002% per second using 6% NaOCl at 40°C. For all irrigation devices tested, the rate of tissue dissolution increased with a higher concentration and temperature of the NaOCl solution.

Conclusions

The novel Multisonic Ultracleaning System achieved a significantly faster tissue dissolution rate when compared with the other systems examined in vitro.     

前路病灶清除植骨内固定结合局部灌洗化疗治疗下颈椎结核伴巨大脓肿

目的:评价前路病灶清除植骨内固定结合术后异烟肼生理盐水持续灌洗局部化疗治疗下颈椎结核伴巨大脓肿的临床疗效.方法:2001年6月～2010年6月收治下颈椎结核伴巨大脓肿患者13例,男8例,女5例;年龄28～62岁,平均44岁.病变累及部位:C3～C4 2例,C4～C5 3例,C5～C6 4例,C5 2例,C6 2例;脓肿累及节段:C3～C6 5例,C3～C7 3例,C4～C7 4例,C4～T1 1例.患者均存在颈部疼痛和不同程度的吞咽及呼吸困难,术前颈部疼痛VAS评分7～10分(8.1±1.3分).10例出现神经功能障碍,JOA评分5～12分(8.3±1.7分).术前血沉78±12mm/h,C反应蛋白65±17mg/L.均在全身抗结核药物治疗下采用颈前路结核病灶清除、钛网填充自体髂骨植骨内固定,术后异烟肼生理盐水持续局部灌洗化疗,并继续全身抗结核治疗12～18个月.随访观察患者临床症状改善、脓肿清除和植骨融合情况.结果:手术均顺利完成,所有患者无术中及术后并发症,术后异烟肼生理盐水持续灌洗14～26d,平均18d.未出现窦道、瘘管和脑脊膜感染.随访24～72个月,平均42个月,血沉和C反应蛋白在术后3个月内均恢复正常,手术节段在3～7个月(平均5.8个月)均得到骨性融合.颈部疼痛VAS评分末次随访时为0～3分(1.5±0.7分),与术前比较有显著性差异(P＜0.05).末次随访时JOA评分为12～17分(14.6±1.5分),与术前比较有显著性差异(P＜0.05).末次随访复查MRI均未见结核复发.结论:在全身规范抗结核药物治疗的前提下,采用前路病灶清除植骨内固定结合术后持续局部灌洗化疗治疗下颈椎结核伴巨大脓肿安全有效,临床效果满意.     

Irrigation with bupivacaine at the surgical bed for postoperative pain relief after laparoscopic cholecystectomy

Purpose:

The aim of this study was to evaluate the effect of bupivacaine irrigated at the surgical bed on postoperative pain relief in laparoscopic cholecystectomy patients.

Methods:

This study included 60 patients undergoing elective laparoscopic cholecystectomy who were prospectively randomized into 2 groups. The placebo group (n=30) received 20cc saline without bupivacaine, installed into the gallbladder bed. The bupivacaine group (n=30) received 20cc of 0.5% bupivacaine in at the same surgical site. Pain was assessed at 0, 6, 12, and 24 hours by using a visual analog scale (VAS).

Results:

A significant difference (P=.018) was observed in pain levels between both groups at 6 hours postoperatively. The average analgesic requirement was lower in the bupivacaine group, but this did not reach statistical significance.

Conclusions:

In our study, the use of bupivacaine irrigated over the surgical bed was an effective method for reducing pain during the first postoperative hours after laparoscopic cholecystectomy.