新疆北疆地区猪Torque teno病毒的PCR检测和序列分析

目的为了解新疆北疆地区猪群中Torque teno virus（TTV）感染流行情况。方法以TTV非编码区保守序列设计引物,采用PCR方法对猪源TTV进行检测,挑选部分阳性样品进行序列分析。结果共检测了该地区109份猪血样,检测结果表明,TTV1的感染率为56．88％（62／109）;TTV2的感染率为22．01％（24／109）;TTV1和TTV2混合感染率为18．34％（20／109）。同时,获得TTV1序列3个,TTV2序列4个,与参考序列相互比对,新疆北疆地区猪TTV1同源性为89．4％～95．2％;TTV2同源性为81．1％～99．2％。结论TTV在新疆北疆猪群中广泛存在,说明猪TTV是一个不容忽视的病原。     

PRELOAD AND TORQUE REMOVAL EVALUATION OF THREE DIFFERENT ABUTMENT SCREWS FOR SINGLE STANDING IMPLANT RESTORATIONS

Several authors still consider the mechanical problems of fracture and component loosening as the main causes of failure of implant-supported restorations. The purpose of this in vitro study was to compare the preload of three types of screw for transmucosal abutment attachment used in single implant-supported prosthesis through strain gauge and removal torque measurements. Three external hex fixtures were used, and each received a transmucosal abutment (Cera One®), which was fixed to the implant with its respective screw: Group A- gold screw, Group B- titanium screw and Group C- surface-treated titanium screw (Ti-Tite®). Ten screws of each type were attached applying a 30.07±0.28 Ncm torque force and maintained in position for 5 minutes. After this, the preload values were measured using strain gauges and a measurement cell. Gold screws presented higher preload values (131.72±8.98 N), followed by surface-treated titanium screws (97.78±4.68 N) and titanium screws (37.03±5.69 N). ANOVA (p<0.05) and Tukey''s test (p<0.05) were applied. Statistically significant differences were found among the groups for both preload and removal torque values. In conclusion, gold screws may be indicated to achieve superior longevity of the abutment-implant connection and, consequently, prosthetic restoration due to greater preload values yielded.     

关于介电单球体细胞电旋转力矩的讨论

本文介绍介电单球体悬浮在旋转电场中旋转力矩的公式推导和两种条件下的频率特征，此理论是分析细胞电旋转的基础。     

自攻型外固定针的研制及性能测试

目的 :介绍一种自攻型外固定针的研制及自攻性能。方法 :标本准备 :成人新鲜尸体胫骨 7根 ,取包埋后胫骨中段为针拧入测试区 ,确定进针点和方向 ,测量胫骨干近侧骨皮质厚度 (a)、髓腔直径 (b)、远侧骨皮质厚度(c) ;测量徒手操作时最大持续轴向压力和旋转力矩 ,借助特制省力扳手 ,将自攻固定针拧入标本 ,利用MTS机施以持续纵向压力 10 0N (A组 )和 15 0N (B组 ) ,操作者以≤ 5Nm的扭矩顺时针旋转扳手拧入外固定针 ,转速为 3 0转 /min。每种测试重复 8次 ,通过MTS传感器记录外固定针各部位在不同轴向压力下所需扭矩、时间和位移。根据时间和各部位的位移计算位移速度。对上述数据进行方差统计分析。结果 :所有外固定针均可被以≤ 5Nm的扭矩徒手拧入。另外 ,(1)每部位A、B 2组间最大扭矩比较无显著性意义 (P >0 .0 5 ) ;近侧皮质处 2组间位移速度比较有显著性意义 (P <0 .0 5 ) ,髓腔、远侧皮质处 2组间比较无显著性意义 (P >0 .0 5 ) ;(2 )每组各部位间最大扭矩比较有显著性意义 (P <0 .0 5 ) ,每组近侧皮质处与髓腔、远侧皮质处的位移速度比较有显著性意义 (P <0 .0 5 ) ,后两者间比较无显著性意义 (P >0 .0 5 )。结论 :改良外固定针具有良好的自攻力学性能 ,可以满足徒手操作的要求。     

不同医用介入指引导管材料和性能的对比研究

目的：研究介入治疗中最常使用的医用指引导管的材料选择、推送力、扭力和扭控性。为更好的研究和指导临床选择使用医用指引导管提供技术依据。方法：对比三家国外厂商医用指引导管的材料组成,通过导管综合性能测试仪,测试三家产品的推送力、扭力和扭控性,并对结果进行分析。结果：三家国外厂商选用的指引导管内层、外层和编制层的材料基本一致。结论：经测试,指引导管到达指定部位所需最大推送力最小,可以较快速的到达病患部位;扭控性好的指引导管,可以较好的处理扭曲血管;旋转两周时所需的扭力最小的指引导管操作性好,可以较好处理解剖复杂的血管。     

Searching for foreign antigens as possible triggering factors of autoimmunity: Torque Teno virus DNA prevalence is elevated in sera of patients with bullous pemphigoid

Objective: The Torque Teno virus (TTV), a member of virus genus Anellovirus has been shown to be commonly present in humans, yet without detectable pathogenicity. Recent studies imply that TTV may contribute to provoke autoimmune progresses in systemic lupus erythematosus and idiopathic inflammatory myopathies. We aimed to study the presence of TTV in a group of patients with autoimmune bullous diseases with a further goal to identify long‐lasting foreign antigen, such as TTV as possible triggers of skin‐specific autoimmunity. Patients and methods: We performed in silico research to study similarities between known TTV sequences and antigens of bullous pemphigoid (BP), pemphigus vulgaris (PV) and dermatitis herpetiformis (DH). Basic Local Alignment Search Tool results showed matching regions for the major BP antigens BP180 and BP230, PV antigen desmoglein 3 and DH antigen transglutaminase 3 and disclosed overlapping, antigen‐predicted sequences only for BP180 regions. We also assessed the prevalence of TTV in these disorders and compared them with the results from two healthy blood donor groups (group 1: sex‐ and age‐matched for the general bullous group, n = 95; group 2: sex‐ and age‐matched for BP, n = 50). Furthermore, we assayed lymphocytes from four TTV DNA and BP180 NC16A blot‐positive BP patients and three controls in a standard lymphocyte transformation test with a TTV peptide from the conserved ORF(Open Reading Frame)1/N22 region. Results: We found that the detection rate of TTV was comparable with that in healthy controls in the group of PV (19/33); whereas detection rates in DH showed a slight, but not significant tendency for elevation (17/20). Contrary, the TTV prevalence in BP patients was significantly elevated (group 1: 36/40 vs group 2: 31/50, P < 0.032). Lymphocytes from all four virus‐positive BP patients heavily reacted to TTV peptide while two of the three healthy controls have shown not to recognize the viral sequences. Only the TTV carrier healthy control had a minor reaction at lowest peptide concentration. The combined in silico, polymerse chain reaction and in vitro cell assay data of the present study indicate that a TTV persistence may contribute to the pathogenesis of BP.     

Reliability of the intelligent stretching device for ankle stiffness measurements in healthy individuals

BackgroundA number of devices have been developed to measure joint stiffness. This study investigated the reliability of the Intelligent (Intel) stretch device to measure bilateral ankle joint stiffness during passive range of motion (ROM).MethodsThe reliability of the device was investigated based on torque and angle by establishing the consistency of measurements between examiners on different testing days. In addition, demographic variables were analyzed to investigate the degree of stiffness. Forty-six gender-matched subjects completed the test.ResultsThe reliability ICC_2,1 coefficient of ankle stiffness between-day for both examiners was 0.77 for the right ankle and 0.76 for the left ankle with a 0.05 standard error of measurement (SEM) for ankle stiffness for the right side and 0.04 for the left side. The ICC values of the two examiners were also high based on Chronbach's alpha (0.87 and 0.86). Among the demographic variables, gender (F = 35.25, p = 0.001) and body weight (F = 23.55, p = 0.001) were the most important factors in determining ankle joint stiffness.DiscussionThe results of this study indicated that dorsiflexion and plantarflexion measurements obtained by the Intel stretch device are reproducible and consistent. In addition, ankle stiffness was significantly different based on gender and body weight to develop and/or maintain ankle function. These results may help to identify ankle stiffness factors that will lead to more efficient rehabilitation programs and injury prevention strategies.     

转矩力作用下托槽槽沟变形的实验研究

目的研究金属及陶瓷托槽在不同大小的转矩力作用下托槽槽沟的变形和断裂情况.方法设计体外装置模拟临床转矩力对托槽的作用,采用电测法和光测法对国内常用的9种正畸托槽在转矩力作用下托槽槽沟的变形和断裂情况进行研究.结果检测样本中3M Victory miniature标准方丝托槽在转矩力作用下发生永久变形所需的力值显著大于其余被检测的托槽;迷你型的金属托槽的强度显著低于标准型托槽;陶瓷托槽抵抗转矩力的强度高于被检测的两种迷你型金属托槽,低于其他金属托槽.结论该装置可真实反映托槽受力情况;本研究中所有的托槽抵抗转矩力的强度均超过了200g·cm,能够满足临床矫治的需要.     

Strength and isometric torque control in individuals with Parkinson’s disease

It has been previously reported that patients with Parkinson’s disease (PD) struggle with fine adjustments of finger forces while manipulating an object. However, impairments in everyday activities can not only be attributed to difficulties with the linear forces applied on an object, but also to the application of rotational forces (torque). This study examined finger strength and isometric torque control in elderly persons with PD. Six individuals with PD (66.1 ± 0.7 years), six elderly healthy controls (65.3 ± 0.2 years) matched by age, gender and handedness, and six young adults (22.3 ± 0.2 years) participated in this study. The subjects were asked to perform two tasks: maximum voluntary thumb-index pinching torque production (MVT) and constant isometric thumb-index torque control at 40% of their MVT for 20 s. The results showed decreased strength and increased difficulty in isometric torque control in individuals with PD as compared to their healthy peers. This study demonstrates that PD affects isometric finger torque production and control. An erratum to this article can be found at     

Allometric scaling of strength measurements to body size

For comparative purposes, normalisation of strength measures to body size using allometric scaling is recommended. A wide range of scaling exponents have been suggested, typically utilising body mass, although a comprehensive evaluation of different body size variables has not been documented. Differences between force (F) and torque (T) measurements of strength, and the velocity of measurement might also explain some of the variability in the scaling exponents proposed. Knee extensor strength of 86 young men was assessed with measurement of torque at four velocities (0–4.19 rad s⁻¹) and force measured isometrically. Body size variables included body mass, height and fat-free mass. Scaling exponents for torque were consistently higher than for force, but the velocity of torque measurement had no influence. As the confounding effects of fat mass were restricted, scaling exponents and the strength of the power-function relationships progressively increased. Fat-free mass determined a surprisingly high proportion of the variance in measured strength (F, 31%; T, 52–58%). Absolute force and torque measurements, and even torque normalised for body mass, were significantly influenced by height, although strength measures normalised to fat-free mass were not. To normalise strength measurements to body mass, for relatively homogenous lean populations (body fat <20%), exponents of 0.66 (F) and 1.0 (T) are appropriate. For more adipose populations (body fat >20%) lower body mass exponents appear more suitable (F, 0.45; T, 0.68). Nevertheless, fat-free mass is the recommended index for scaling strength to body size, and higher exponents (F, 0.76; T, 1.12) are advocated in this case.