A simple selection system for construction of recombinant gD-negative pseudorabies virus as a vaccine vector.

We describe a simple, efficient two-step method for construction of glycoprotein D (gD)-negative pseudorabies virus (PrV) carrying transgenes inserted in place of the gD gene. The first step was the use of the thymidine kinase (TK) gene of herpes simplex virus (HSV) for insertional inactivation of the gD gene in a PrV mutant deficient in both TK and glycoprotein E (gE). The gD-negative, HSV-TK-positive mutant could be selected in HAT medium. The second step was substitution of HSV-TK with other genes of interest. The resultant gD/gE/TK-negative mutant was easily isolated by acyclovir selection. The expression of the transgene was detectable in vivo and the antibody responses against both inserted antigens and PrV were induced. The protective efficacy of the gD/gE/TK-negative PrV against lethal PrV challenge was also demonstrated. This PrV mutant carrying immunogenic proteins from unrelated porcine pathogens may be tested as a multivalent vaccine candidate for swine.     

Electromyographic study of motor learning for a voice production task.

PURPOSE: This study's broad objective was to examine the effectiveness of surface electromyographic (EMG) biofeedback for motor learning in the voice production domain. The specific objective was to examine whether concurrent or terminal biofeedback would facilitate learning for a relaxed laryngeal musculature task during spoken reading. METHOD: Twenty-two healthy adult speakers were randomly assigned to 1 of 2 groups. One group received real-time EMG waveform displays of muscle activation from bilateral thyrohyoid sites during reading trials (concurrent feedback group). The other group received static terminal EMG waveform displays about activation levels for the same sites on completion of successive trials (terminal feedback group). All participants were instructed to minimize EMG amplitudes from the thyrohyoid sites during phonation in an oral reading task. Signals were also collected from control, orofacial sites, but participants received neither instructions nor feedback for those sites. RESULTS: The pooled data (2 feedback groups x 2 electrode sites) showed that, overall, muscle activation levels did decrease across baseline, training, and no-feedback test phases. However, no clear evidence was seen of reliable changes in the targeted laryngeal muscle activation levels across the phases, for either the concurrent or the terminal feedback groups. Paradoxically, and entirely unanticipated, reliable decreases were seen in muscle activation for the orofacial, no-feedback control sites. Those decreases were equivalent across concurrent and terminal feedback groups. CONCLUSIONS: The unanticipated findings indicate that the provision of biofeedback for a target muscle group facilitated incidental learning in another, untargeted muscle group. Discussion focuses on the possible role of locus of attention in motor learning. Building on literature from other domains, the hypothesis is advanced that attention to muscular contractile force during training trials may suppress intentional learning for attended target sites but may benefit incidental learning for nearby, unattended sites.     

Combined endo‐laparoscopic approach in managing patients with gallstones and common bile duct stones: An early experience

Gallstones with common bile duct stones is a common condition in Hong Kong. Management still remains a challenge nowadays. Laparoscopic cholecystectomy with intraoperative endoscopic retrograde cholangiopancreatography (ERCP) is a single‐stage approach which improves patient comfort and is associated with less post‐ERCP pancreatitis. With the new endo‐laparoscopic operating theatre in service, the combined endo‐laparoscopic approach becomes simple and practical. We report here our two early experiences using this approach.     

长骨干骨折脂肪栓塞综合征患者内固定植入物及其方式的选择：26例随访分析

目的:通过长骨干骨折脂肪栓塞综合征患者内固定植入物及其方式的合理选择,以最大限度减少手术创伤及减少对骨折端的刺激,有效避免脂肪栓塞综合征的复发。方法:①对象:选择1998-02/2006-03唐山市第二医院创伤科收治长骨干骨折行内固定植入的脂肪栓塞综合征患者26例。②方法:采用非扩髓髓内钉固定股骨干、胫骨干中段骨折及多段骨折、微创经皮钢板内固定股骨干远端骨折及胫骨干远近端骨折、钢板固定肱骨干、桡骨骨折;术后早期进行系统的康复治疗;并接受随访。术后定期复查X线片,并观察材料及宿主反应。结果:①术后随访:16例患者术后随访12～24个月,10例患者随访25～108个月。②X线摄片评定骨折愈合结果:长骨干骨折髓内钉固定于术后10～17周临床愈合;微创经皮钢板固定,于术后9～19周临床愈合;钢板固定,于术后13～20周临床愈合。无髓内钉松动及断钉、断板等并发症,肌力5级,未发现脂肪栓塞综合征后遗症。③植入物与组织的生物相容性能评估:术后无切口感染、局部炎症反应、排异反应。结论:对于长骨干骨折的脂肪栓塞综合征患者,非扩髓髓内钉、微创经皮钢板及钢板3种内固定植入物及植入方式均可满足不同部位及类型长骨干骨折的需要,植入物与人体具有良好的生物相容性,不增加脂肪栓塞综合征复发率及后遗症。     

Fe<Subscript>3</Subscript>O<Subscript>4</Subscript>-PEI-RITC Magnetic Nanoparticles with Imaging and Gene Transfer Capability: Development of a Tool for Neural Cell Transplantation Therapies

Purpose  

To develop Fe₃O₄-PEI-RITC magnetic nanoparticles with multimodal MRI-fluorescence imaging and transfection capability, for use in neural cell replacement therapies.