Ultrasound Measurements of the First Extensor Compartment: Determining the Transection Limits for Ultra-minimally Invasive Release of De Quervain Tenosynovitis

Background: De Quervain syndrome is the second most common compressive tendinopathy. Although the length of the first extensor compartment (FEC) has been studied previously, there is no documented reported comparison study of short-axis and long-axis sonographic measurements. The thread technique, or Guo Technique, has been applied to carpal tunnel syndrome, trigger finger, and superficial peroneal compressive neuropathy. To perform this procedure, it is critically important to accurately identify the boundaries for transection. Methods: Twenty-one fresh frozen cadaver upper extremities were examined under ultrasound to determine the length of the extensor retinaculum (ER) over the FEC. Using the sonographic landmarks, the ERs were measured in short axis and long axis over their proximal to distal margins and from the distal margins to the distal edges of the radial styloids. These sonographic measurements were then compared with gross anatomical measurements. Results: The short-axis sonographic measurement of the ER on average was 22.53 mm (95% confidence interval [CI] = 20.79-24.05 mm). The long-axis sonographic measurement of the ER on average was 15.65 mm (95% CI = 13.70-17.78 mm). The average length of the ER by gross anatomical dissection was 22.40 mm (95% CI = 21.15-23.51 mm). Conclusions: The short axis is not significantly different from the gross anatomical measurement; however, the long axis is significantly lower than the gross anatomical measurement. The results support the idea that the short axis is more accurate than the long axis.     

Nutritional status of students practicing fencing atttending sports schools

Aim

The aim of this research was to assess the influence of various factors on nutritional status in children and adolescents practicing fencing and to carry out a detailed analysis of nutritional status in the studied population, taking into account the most significant variable.

Current knowledge

One of the most important issues of human nutrition is the assessment of nutritional status of children and adolescents, especially those who practice sport. There are still a lot of gaps in the knowledge on nutritional status of young athletes. The reason for this is a variety of sports disciplines and forms of training which requires detailed research and screening of young athletes’ growth and development.

Prospects

In the studied population of children and adolescents practicing fencing typical gender differences in body stature and body composition occurring with age were observed, as well as favourable changes in blood lipid profile, glucose level and haematological indices.     

Nanocomposites of lung surfactant and biodegradable cationic nanoparticles improve transfection efficiency to lung cells

The objective of this study was to develop highly efficient ternary nanocomposites for aerosol gene therapy consisting of a biodegradable polymer core, poly[vinyl-3-(diethylamino)propylcarbamate-co-vinyl acetate-co-vinyl alcohol]-graft-poly(d,l-lactide-co-glycolide), pDNA and a third component to alter surface properties, physicochemical characteristics and biological activity. The effects of the surface altering components lung surfactant, carboxymethyl cellulose (CMC) or poloxamer on nanocomposites were characterized with regard to size, zeta potential, cytotoxicity, biological activity and surface properties. With increasing concentrations of lung surfactant, CMC or poloxamer, sizes of nanocomposites increased. AFM nanoindentation measurements showed a significant increase in adhesion forces of nanocomposites compared to pure nanoparticles. Zeta potential values, cytotoxicity and intracellular uptake demonstrated a strong dependency on the surface altering component. While an excess of CMC led to a decreased uptake into cells due to the negative zeta potential, nanocomposites with lung surfactant displayed enhanced intracellular uptake. Transfection efficiency of nanocomposites with lung surfactant was 12-fold higher compared to pure nanoparticles and 30-fold higher compared to polyethylenimine in lung cells and could also be maintained after nebulization. Ternary nanocomposites prepared with lung surfactant proved to be a potent pulmonary gene delivery vector due to its high stability during aerosolization with a vibrating mesh nebulizer and favourable biological activity.     

Lung volume calculated from electrical impedance tomography in ICU patients at different PEEP levels

Purpose  To study and compare the relationship between end-expiratory lung volume (EELV) and changes in end-expiratory lung impedance (EELI) measured with electrical impedance tomography (EIT) at the basal part of the lung at different PEEP levels in a mixed ICU population. Methods  End-expiratory lung volume, EELI and tidal impedance variation were determined at four PEEP levels (15–10–5–0 cm H₂O) in 25 ventilated ICU patients. The tidal impedance variation and tidal volume at 5 cm H₂O PEEP were used to calculate change in impedance per ml; this ratio was then used to calculate change in lung volume from change in EELI. To evaluate repeatability, EELV was measured in quadruplicate in five additional patients. Results  There was a significant but relatively low correlation (r = 0.79; R ² = 0.62) and moderate agreement (bias 194 ml, SD 323 ml) between ∆EELV and change in lung volume calculated from the ∆EELI. The ratio of tidal impedance variation and tidal volume differed between patients and also varied at different PEEP levels. Good agreement was found between repeated EELV measurements and washin/washout of a simulated nitrogen washout technique. Conclusion  During a PEEP trial, the assumption of a linear relationship between change in global tidal impedance and tidal volume cannot be used to calculate EELV when impedance is measured at only one thoracic level just above the diaphragm. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Effect of tidal volume in children with acute hypoxemic respiratory failure

Objectives  To determine if tidal volume (V _T) between 6 and 10 ml/kg body weight using pressure control ventilation affects outcome for children with acute hypoxemic respiratory failure (AHRF) or acute lung injury (ALI). To validate lung injury severity markers such as oxygenation index (OI), PaO₂/FiO₂ (PF) ratio, and lung injury score (LIS). Design  Retrospective, January 2000–July 2007. Setting  Tertiary care, 20-bed PICU. Patients  Three hundred and ninety-eight endotracheally intubated and mechanically ventilated children with PF ratio <300. Outcomes were mortality and 28-day ventilator free days. Measurements and main results  Three hundred and ninety-eight children met study criteria, with 20% mortality. 192 children had ALI. Using >90% pressure control ventilation, 85% of patients achieved V _T less than 10 ml/kg. Median V _T was not significantly different between survivors and non-survivors during the first 3 days of mechanical ventilation. After controlling for diagnostic category, age, delta P (PIP-PEEP), PEEP, and severity of lung disease, V _T was not associated with mortality (P > 0.1), but higher V _T at baseline and on day 1 of mechanical ventilation was associated with more ventilator free days (P < 0.05). This was particularly seen in patients with better respiratory system compliance [Crs > 0.5 ml/cmH₂0/kg, OR = 0.70 (0.52, 0.95)]. OI, PF ratio, and LIS were all associated with mortality (P < 0.05). Conclusions  When ventilating children using lung protective strategies with pressure control ventilation, observed V _T is between 6 and 10 ml/kg and is not associated with increased mortality. Moreover, higher V _T within this range is associated with more ventilator free days, particularly for patients with less severe disease. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Development and calibration of a γ-ray density-meter for sediment-like materials

The core-logger PHAROS was designed at Kernfysisch Versneller Instituut, Groningen, the Netherlands to measure activity concentration of sediment like materials. As the core logger was calibrated for a single material density the variations in the density profile in the scanned core can result in erroneous estimations of activity concentrations. To overcome this, a density-meter was developed and implemented on PHAROS. The density measurement should be non-invasive and should cover a wide range of sediment like materials. The most suitable approach is to deploy γ-ray transmission technique, where the intensity of non-attenuated photons after traversing the core is directly related to its density. Due to the overall complexity of radiation transport through sediment media, the design of the density-meter was assisted by Monte Carlo simulations. They were deployed to model sophisticated and time-consuming experiments in the process of designing the ¹³⁷Cs-based source, to generate the pulse-height response functions of the bismuth-germanate (BGO) scintillator and to estimate the systematic uncertainty induced by the core displacement in the process of the measurement. Moreover, the Monte Carlo simulations have demonstrated as a reliable complementary tool for the generation of PHAROS detector calibration curves. The designed density-meter of PHAROS core-logger indicates to be adequate to estimate densities ranging from 1.6 to 2.7 g cm⁻³ with the systematic uncertainty within 3%.     

化学发光法定量检测乙型肝炎病毒标志物临床应用评价

目的对化学发光法定量检测乙型肝炎病毒标志物的临床应用进行评价。方法用标准参考血清和定值质控血清,对化学发光法定量检测乙型肝炎病毒标志物进行评价,评价内容为符合率、分析灵敏度、分析特异性、批内和批间精密度、最低检出限等指标。结果HBsAg符合率为97．5％,其他四项符合率大于92％;HBsAg分析灵敏度100％、分析特异性96．15％;五项的批内和批间精密度均小于15％;最低检出限分别为HBsAg0．06IU／mL、HBsAb0．5mIU／mL、HBeAg0．05NCU／mL、HBeAb0．5NCU／mL、HBcAb0．5NCU／mL。结论化学发光法定量检测乙型肝炎病毒标志物各项性能指标能满足临床要求,但操作需注意标本质量。     

邻牙向拔牙区移动最佳时机选择的实验研究

目的　研究拔牙创愈合的生理过程和牙齿向拔牙区移动的生物学反应,探讨邻牙向拔牙区移动的最佳时机。方法　30只同源雄性SD大鼠分为5组,拔除上颌第一磨牙,在拔牙后不同的时间制作口内矫治器,牵第二磨牙向拔牙区移动。所有的大鼠分别在矫治器加力前两天和处死前两天给予四环素和钙黄绿素腹腔注射;制备硬组织切片,采用骨硬组织形态测量和计算机图像处理技术,对向处于不同愈合阶段的拔牙区移动牙齿时的骨改建参数进行定量分析。结果　①骨改建同时包括吸收和形成两个过程;②近中牙槽骨面(压力侧)骨吸收较远中 (张力侧)活跃,而远中牙槽骨面(张力侧)骨形成则较近中(压力侧)活跃;③骨形成参数、骨吸收参数均在拔牙后1 周存在一个峰值。结论　①拔牙后宜早期移动牙齿,以便充分利用拔牙创的骨改建优势;②其理想的移动时机为拔牙后1周左右。     

NEMA标准(2001版)新增内容

本文是在NEMA公布的1994年版本NEMA标准的基础上,将2001年版本NEMA标准的新增内容(包括:2.5系统对准和3.10探头间灵敏度变化)和修改内容(包括:3.8系统平面灵敏度与穿透和3.9探头屏蔽)译出。