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Background

Tachyarrhythmia after esophagectomy is a severe complication that should not be underestimated because of its negative impact. The aims of this study were to clarify the cause and impact of postoperative tachyarrhythmia after thoracoscopic esophagectomy. Additionally, we analyzed the usefulness of landiolol administration for postoperative tachyarrhythmia.

Methods

We evaluated the predictive factors for tachyarrhythmia onset after surgery and its clinical impact in 127 patients who underwent thoracoscopic esophagectomy with extended lymphadenectomy. Moreover, we analyzed the efficacy of landiolol for postoperative tachyarrhythmia.

Results

Tachyarrhythmia developed in 38 of the 127 patients. Multivariate analysis showed that advanced age, heart disease, and hyperlipidemia were associated with postoperative tachyarrhythmia. Hyponatremia, hypoalbuminemia, and leukocytosis on postoperative day 3 were significantly associated with tachyarrhythmia onset. The incidence of all complications and respiratory complications, including pneumonia, was significantly higher in patients with than in those without tachyarrhythmia. The mortality rate in the tachyarrhythmia group tended to be higher than that in the nontachyarrhythmia group. Landiolol as a treatment for tachyarrhythmia immediately decreased heart rate and safely reduced subsequent respiratory complications.

Conclusion

In elderly patients with cardiac disease or hyperlipidemia, surgeons should be alert for the occurrence of tachyarrhythmia after esophagectomy. Postoperative tachyarrhythmia is a marker of morbidities with particular emphasis on respiratory complications. However, it can be adequately managed by landiolol, resulting in fewer respiratory complications. Landiolol might be a safe and convenient agent for managing postoperative tachyarrhythmia after thoracoscopic esophagectomy, resulting in lower mortality and morbidity rates.  相似文献   
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NOD/LtSzscid/IL‐2Rγ?/? (NSG) mice have advantages in establishing humanized mouse models. However, transferring human PBMCs into these mice often causes lethal GVH disease. In this study, we discovered an improved method for the engraftment of normal or pathological human PBMCs into NSG mice and examined the subsequent induction of specific immune responses. We sequentially transferred human CD4+ memory T (Tm) and B cells obtained from PBMCs of healthy adults or patients with autoimmune diseases into NSG mice. Removing naïve CD4+ T cells from the transferred PBMCs allowed successful engraftment without lethal GVH disease. The transferred Tm cells were found to reside mainly in the spleen and the lymphoid nodules, where they expressed MHC class II molecules and produced cytokines, including IL‐21. Surprisingly, the transferred B cells were also well maintained in the lymphoid organs, underwent de novo class‐switch recombination, and secreted all isotypes of human Igs at significant levels. Moreover, transferring patient‐derived Tm and B cells resulted in sustained production of IgM‐rheumatoid factor and antiaminoacyl transfer RNA synthetase Abs in these mice. These results suggest that transfer of Tm and B cells derived from human PBMCs into NSG mice could be a useful method for the study of human autoimmune mechanisms.  相似文献   
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Formation of precise and high-resolution silica micropatterns on polymer substrates is of importance in surface structuring for flexible device fabrication of optics, microelectronic, and biotechnology. To achieve that, substrates modified with affinity-patterns serve as a strategy for site-selective deposition. In the present paper, vacuum ultraviolet (VUV) treatment is utilized to achieve spatially-controlled surface functionalization on a cyclo-olefin polymer (COP) substrate. An organosilane, 2,4,6,8-tetramethylcyclotetrasiloxane (TMCTS), preferentially deposits on the functionalized regions. Well-defined patterns of TMCTS are formed with a minimum feature of ∼500 nm. The secondary VUV/(O)-treatment converts TMCTS into SiOx, meanwhile etches the bare COP surface, forming patterned SiOx/COP microstructures with an average height of ∼150 nm. The resulting SiOx patterns retain a good copy of TMCTS patterns, which are also consistent with the patterns of photomask used in polymer affinity-patterning. The high quality SiOx patterns are of interests in microdevice fabrication, and the hydrophilicity contrast and adjustable heights reveal their potential application as a “stamp” for microcontact printing (μCP) techniques.

Patterned surface treatment on a polymer substrate is carried out by 172 nm VUV through a photomask. TMCTS pattern formation is guided by the resulting affinity-pattern. The secondary VUV treatment converted TMCTS patterns into silica patterns.  相似文献   
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