Peripheral Blood Neutrophil Activity During Dermatophagoides pteronyssinus-Induced Late-Phase Airway Inflammation in Patients with Allergic Rhinitis and Asthma

Recent investigations suggest that neutrophils may play an important role in the late-phase allergen-induced inflammation in allergic airway diseases. The aim of this study was to evaluate neutrophil chemotaxis, phagocytic activity, and reactive oxygen species (ROS) production in patients with allergic rhinitis and asthma challenged with inhaled Dermatophagoides pteronyssinus. Eighteen patients with allergic rhinitis and 14 with allergic asthma, all sensitized to D. pteronyssinus, as well as 15 healthy individuals underwent bronchial challenge with D. pteronyssinus. Peripheral blood collection and neutrophil isolation were performed 24 h before as well as 7 and 24 h after bronchial challenge. Neutrophils chemotaxis, phagocytic activity, and ROS production were analyzed by flow cytometer. Neutrophil chemotaxis and ROS production were increased, while phagocytic activity was decreased 24 h before challenge in patient groups compared with healthy individuals. After challenge, neutrophil chemotaxis and phagocytic activity increased after 7 and 24 h, when ROS production, only after 24 h. Bronchial allergen challenge had no influence for neutrophils activity in healthy subjects. Activated chemotaxis, phagocytic activity, and ROS production of peripheral blood neutrophils after challenge with D. pteronyssinus reflect an enhanced systemic inflammation in allergic rhinitis and asthma patients with induced late-phase airway inflammation.     

The colonization of Peyer's patches by a strain of Salmonella typhimurium cured of the cryptic plasmid

We cured a strain of Salmonella typhimurium of its cryptic plasmid and confirmed that orally administered cured strains lost virulence for mice. Loss of the cryptic plasmid rendered the S. typhimurium strain sensitive to the bactericidal action of normal human serum. However, loss of the plasmid did not change the ability of the strain to associate with HeLa cells in tissue culture. Furthermore, when administered orally to mice, both the plasmid-containing and plasmid-free strains invaded the Peyer's patches of the small intestine to the same extent, and both were capable of inducing resistance to oral challenge with virulent S. typhimurium. When injected intraperitoneally, the cured strain was eliminated rapidly, whereas the parental strain persisted. We also showed that the cured strain did not contain a plasmid copy in the chromosome. We propose that although the plasmid-cured strain of S. typhimurium is able to colonize Peyer's patches, it cannot survive when administered intraperitoneally because it is susceptible to elimination by macrophages.     

Configuration optimization and experimental accuracy evaluation of a bone-attached,parallel robot for skull surgery

Purpose

Minimally invasive cochlear implantation is a novel surgical technique which requires highly accurate guidance of a drilling tool along a trajectory from the mastoid surface toward the basal turn of the cochlea. The authors propose a passive, reconfigurable, parallel robot which can be directly attached to bone anchors implanted in a patient’s skull, avoiding the need for surgical tracking systems. Prior to clinical trials, methods are necessary to patient specifically optimize the configuration of the mechanism with respect to accuracy and stability. Furthermore, the achievable accuracy has to be determined experimentally.

Methods

A comprehensive error model of the proposed mechanism is established, taking into account all relevant error sources identified in previous studies. Two optimization criteria to exploit the given task redundancy and reconfigurability of the passive robot are derived from the model. The achievable accuracy of the optimized robot configurations is first estimated with the help of a Monte Carlo simulation approach and finally evaluated in drilling experiments using synthetic temporal bone specimen.

Results

Experimental results demonstrate that the bone-attached mechanism exhibits a mean targeting accuracy of \((0.36\pm 0.12)\) mm under realistic conditions. A systematic targeting error is observed, which indicates that accurate identification of the passive robot’s kinematic parameters could further reduce deviations from planned drill trajectories.

Conclusion

The accuracy of the proposed mechanism demonstrates its suitability for minimally invasive cochlear implantation. Future work will focus on further evaluation experiments on temporal bone specimen.

     

鸭IL-2cDNA及基因组序列的初步分析

从鸭外周血分离的单核细胞在体外经PHA (5 μg/ml)刺激 2 0h后 ,提取总RNA及mRNA并通过逆转录制备cDNA。采用最近克隆的鸡白细胞介素 2 (ChIL 2 )cDNA序列为探针对cDNA进行Southernblot杂交 ,以识别鸭白细胞介素 2 (DuIL 2 )特异的cDNA序列。从鸭外周血单核细胞中提取的基因组DNA经限制性内切酶BamHI、EcoRI、XbaI消化后 ,以上述探针进行杂交 ,分析DuIL 2基因组序列。结果表明 ,无论是鸭cDNA或基因组DNA ,经Southern杂交后 ,均得到特异性杂交条带 ,证实ChIL 2与DuIL 2具有较高序列同源性。DuIL 2mRNA表达时形成两种转录子 ,大小分别为 95 9bp、 780bp。同鸡γ 干扰素(ChIFN γ )探针产生的杂交信号比较 ,ChIL 2产生的杂交信号相对较弱 ,推测可能和DuIL 2mRNA在上述条件下拷贝数相对较少以及ChIL 2与DuIL 2cDNA序列同源性相对较低有关