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Branched polyolefins with controllable topology structures were generated from the chain-walking (co)polymerizations of ethylene, 1-pentene (1P) and 2-pentene (2P) using Brookhart-type a-diimine Ni(II)-based catalysts possessing different para-substituted groups, {[(4-R-2-Et-6-Me-C6H2N = C)2Nap]NiBr2, Nap: 1,8-naphthdiyl; R = CHMePh, Ni1; R = Ph, Ni2; R = H, Ni3}. The X-ray diffraction analysis demonstrated that the crystalline structure of Ni1' is in centrosymmetric dimer structure mode with the bimetallic Ni center connected by two bromide bridges. The para-sec-phenethyl moiety in the catalyst Ni1 obviously improved its catalytic performance and thermal stability in the ethylene polymerization. The Ni1/Et2AlCl system showed great catalytic activities (up to 7.73×106 g·mol−1·h−1) and achieved polyethylene (PE) with alkyl chains, including Me, Et, n-Pr, n-Bu, sec-Bu branches and longer chains (Lg). Compared with the 1-pentene polymerization, this catalyst system successfully mediated the polymerization of 2P to give highly branched polymers with approximately 195 branches/1000C possessing Me, Et, and n-Pr branches and a long methylene sequence due to the monomer isomerization. The Et branches derived from 2,3-insertion is slightly less than the sum of Me and n-Pr branches derived from 3,2-insertion, indicating that the 3,2-insertion mode is a slightly favorable pathway in the polymerization of 2P. [ABSTRACT FROM AUTHOR]

Objective To evaluate the effects of ultrasound-guided transversus abdominis plane (TAP) block on postoperative analgesia and early recovery in patients undergoing retroperitoneoscopic urologic surgeries. Methods This was a randomized, controlled, double-blinded trial. Eligible patients scheduled for retroperitoneoscopic urologic surgeries were randomly assigned to two groups. Group TAP received ultrasound-guided TAP block with 0.5% ropivacaine 20 ml at 30 minutes before surgery, and Group C received TAP sham block with normal saline. All patients received retroperitoneoscopic urologic surgeries under general anesthesia. The primary outcome was the severity of pain after surgery. Secondary outcomes included opioids consumption, analgesics, postoperative nausea and vomiting, time to Foley catheter removal and to passage of flatus, length of post-anesthesia care unit stay and hospital stay. Results Eighty patients completed the study, forty cases in each group. Compared to the Group C, the Group TAP had lower visual analogue scale pain scores within two postoperative days (all P <0.05). They also had less consumption of intraoperative fentanyl (2.0±0.5 vs. 3.8±0.7 μg/kg, P <0.05), reduced incidence of postoperative rescue analgesic usage (12.5% vs. 45.0%, P <0.05), and lower incidence of postoperative nausea and vomiting within postoperative 48 hours (12.5% vs. 25.0%, P <0.05) when compared to the Group C. In addition, Group TAP had a shortened post-anesthesia care unit stay (25±8 vs. 49±12 minutes, P <0.05), and a greater proportion of patients discharged within postoperative three days (57.5% vs. 35.0%, P <0.05). Conclusion Preoperative ultrasound-guided TAP block is an effective technique to improve postoperative analgesia and early recovery in patients undergoing retroperitoneoscopic urologic surgeries. [ABSTRACT FROM AUTHOR]

Background: CD8+ T cells (Cytotoxic T cells, Tc) are known to play a critical role in the pathogenesis of smoking related airway inflammation including chronic obstructive pulmonary disease (COPD). However, how cigarette smoke directly impacts systematic CD8+ T cell and regulatory T cell (Treg) subsets, especially by modulating muscarinic acetylcholine receptors (MRs), has yet to be well elucidated. Methods: Circulating CD8+ Tc/Tregs in healthy nonsmokers (n = 15), healthy smokers (n = 15) and COPD patients (n = 18) were evaluated by flow cytometry after incubating with anti-CD3, anti-CD8, anti-CD25, anti-Foxp3 antibodies. Peripheral blood T cells (PBT cells) from healthy nonsmokers were cultured in the presence of cigarette smoke extract (CSE) alone or combined with MRs agonist/antagonist for 5 days. Proliferation and apoptosis were evaluated by flow cytometry using Ki-67/Annexin-V antibodies to measure the effects of CSE on the survival of CD8+ Tc/Tregs. Results: While COPD patients have elevated circulating percentage of CD8+ T cells, healthy smokers have higher frequency of CD8+ Tregs. Elevated percentages of CD8+ T cells correlated inversely with declined FEV1 in COPD. CSE promoted the proliferation and inhibited the apoptosis of CD8+ T cells, while facilitated both the proliferation and apoptosis of CD8+ Tregs. Notably, the effects of CSE on CD8+ Tc/Tregs can be mostly simulated or attenuated by muscarine and atropine, the MR agonist and antagonist, respectively. However, neither muscarine nor atropine influenced the apoptosis of CD8+ Tregs. Conclusion: The results imply that cigarette smoking likely facilitates a proinflammatory state in smokers, which is partially mediated by MR dysfunction. The MR antagonist may be a beneficial drug candidate for cigarette smoke-induced chronic airway inflammation. [ABSTRACT FROM AUTHOR]

Objective Although repeat microvascular decompression (MVD) for hemifacial spasm (HFS) in patients with failed prior MVD is potentially curative, little is known about the long-term results of repeat MVD. We aimed to evaluate the long-term outcomes and complications after repeat MVD for HFS. Methods We performed repeat MVD on 78 consecutive patients who had undergone a prior MVD >1 year previously. Follow-up data were available for 58 patients, with a median follow-up period of 8.6 years (range, 6.9–10.2 years). The patients were assessed for intraoperative findings, relief results, and complications at discharge and at follow-up, as well as the associations between the preoperative characteristics and outcomes. Results At discharge, of 78 patients with repeat MVD, 72 (92.3%) achieved complete spasm resolution and 1 (2.6%) had significantly improved spasm resolution. Of all patients, 9% (7 of 78) presented short-term complications, including partial hearing loss, hemifacial paresis, and cerebrospinal fluid leak. At follow-up, 45 of 58 (77.6%) patients had complete relief and 10 of 58 (17.2%) had improved relief. Permanent complications occurred in 14 patients (24.1%), with partial hearing loss and mild hemifacial paresis being the most common. Despite the complications, 51 of 58 patients (91.4%) reported an excellent life quality. No significant correlation was found between preoperative characteristics, such as age, interval to prior MVD, or interval to recurrence, and outcomes including short-term or long-term relief results and complications. Conclusions Repeat MVD provides lasting relief for most patients with persistent or recurrent HFS, albeit with a relatively high complication rate. [ABSTRACT FROM AUTHOR]