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21.
We synthesized self-assembled nucleobases (SANs), such as 1-dodecylthymine (DOT) or 9-dodecyladenine (DOA), in which the nucleobase is immobilized on a long alkyl chain. The thermal stability of the SAN was increased by mixing with the acidic surfactant mono-dodecyl phosphate (MDP). Additionally, the SAN–MDP composite material showed proton conductivity of 4.62 × 10−4 S cm−1 at 160 °C under anhydrous conditions. Additionally, the activation energy of the proton conduction was approximately 0.2 eV and this value was one order of magnitude higher than that of a typical humidified perfluorinated membrane, in which the proton can be moved by vehicle molecules, such as water molecules. In contrast, when the nucleobase without the immobilization of a long alkyl chain was mixed with MDP, the proton conductivity of these composite materials was two orders of magnitude less than that of the SAN–MDP composite. Therefore, we measured the XRD spectra of the SAN–MDP composite material. As a result, the SAN–MDP composite material showed a self-assembled structure with a two-dimensional proton conducting pathway, such as a lamellar structure, and that the anhydrous proton conduction was related to the interaction between the nucleobase of the SAN and the phosphate group of MDP. Consequently, the self-assembled nucleobase derivatives have the potential for use as novel anhydrous proton conductors with a two-dimensional proton conducting pathway.

We synthesized the proton conductive self-assembled nucleobase, such as 1-dodecylthymine and 9-dodecyladenine, in which the nucleobase is immobilized on a long alkyl chain.  相似文献   
22.
23.
Regulatory T cells (Tregs) are critical mediators of immune homeostasis and hold significant promise in the quest for transplantation tolerance. Progress has now reached a critical threshold as techniques for production of clinical therapies are optimised and Phase I/II clinical trials are in full swing. Initial safety and efficacy data are being reported, with trials assessing a number of different strategies for the introduction of Treg therapy. It is now more crucial than ever to elucidate further the function and behaviour of Tregs in vivo and ensure safe delivery. This review will discuss the current state of the art and future directions in Treg therapy.  相似文献   
24.
Background:Plasma fibrinogen is considered a biomarker of respiratory disease, owing to the relationship between plasma fibrinogen and pulmonary function established in Western populations. However, such a relationship has not yet been confirmed in an Asian population. We assessed this relationship in the general Japanese population.Methods:Totally, 3,257 men and women aged ≥40 years who participated in a community-based annual health checkup in Takahata, Japan, from 2004 to 2006, underwent spirometry, and their plasma fibrinogen levels were determined.Results:We found an inverse relationship between spirometric measures (percent predicted forced vital capacity [%FVC] and forced expiratory volume in 1s [%FEV1], and FEV1/FVC) and plasma fibrinogen levels in men, but not in women. The plasma fibrinogen levels were significantly higher in subjects with restrictive, obstructive, and mixed ventilatory disorders than in those with normal spirometry results. Multiple linear regression analysis revealed that in men, plasma fibrinogen levels were predictive for %FVC and %FEV1 (independent of age, body mass index, and cigarette smoking) but not for FEV1/FVC.Conclusions:Plasma fibrinogen was significantly associated with pulmonary function in Japanese men, and as such, plasma fibrinogen might be a potent biomarker for pulmonary dysfunction in men.  相似文献   
25.

Introduction

Stem cells isolated from the root apical papilla of human teeth (stem cells from the apical papilla [SCAPs]) are capable of forming tooth root dentin and are a feasible source for bioengineered tooth root regeneration. In this study, we examined the effect of acetylsalicylic acid (ASA) on odontogenic differentiation of SCAPs in vitro and in vivo.

Methods

SCAPs were cultured under odontogenic conditions supplemented with or without ASA. ASA-treated SCAPs were also subcutaneously transplanted into immunocompromised mice.

Results

ASA accelerates in vitro and in vivo odontogenic differentiation of SCAPs associated with down-regulation of runt-related nuclear factor 2 and up-regulation of specificity protein 7, nuclear factor I C, and dentin phosphoprotein. ASA up-regulated the phosphorylation of AKT in the odontogenic SCAPs. Of interest, pretreatments with phosphoinositide 3-kinase inhibitor LY294402 and small interfering RNA for AKT promoted ASA-induced in vitro and in vivo odontogenic differentiation of SCAPs. LY294402 and small interfering RNA for AKT also suppressed the ASA-induced expression of runt-related nuclear factor 2 and enhanced ASA-induced expression of specificity protein 7, nuclear factor I C, and dentin phosphoprotein in SCAPs.

Conclusions

These findings suggest that a combination of ASA treatment and suppressive regulation of the phosphoinositide 3-kinase–AKT signaling pathway is a novel approach for SCAP-based tooth root regeneration.  相似文献   
26.
Clinical and Experimental Nephrology - Peritoneal dialysis (PD) catheter malposition is one of the complications of renal replacement therapy. This study aimed to determine the preoperative factors...  相似文献   
27.

In the treatment of an intracranial aneurysm with the flow diverter, the combined use of coil embolization can help promote subsequent progressive thrombosis within the aneurysm sac and reduce the risk of delayed aneurysm rupture. This study retrospectively reviewed outcomes of patients who had undergone the Pipeline Embolization Device (PED) with adjunctive coil embolization (PED/coil) at a single center to determine its safety and efficiency. Patients with internal carotid artery aneurysms following an intradural component were selected for PED/coil between 2015 and 2020. All patients were premedicated with dual antiplatelet therapy of aspirin plus clopidogrel or prasugrel. A minimal number of PEDs were deployed, with coils inserted using a stent-jail technique, avoiding dense packing. A total of 46 aneurysms (43 patients; median dome size, 11.6 mm; median neck width, 6.3 mm) were treated with PED/coil. The median volume embolization ratio was 14.8%. The degree of angiographic filling at the 6-month and latest angiography showed complete occlusion in 60.5% (26/43) and 70.5% (31/44), respectively. Small (<?10 mm) aneurysms achieved a higher complete occlusion rate in the early period; a lower cumulative incidence of aneurysm occlusion was observed in large and giant (≥?10 mm) aneurysms (P?=?.024). The median clinical follow-up was 22 months, and no aneurysm ruptures occurred. Favorable clinical outcomes were achieved, with permanent neurological morbidity of 4.7% and no mortality. PED/coil demonstrated a high angiographic occlusion rate at an early stage. Loosely packed coils are sufficient to obliterate aneurysms effectively.

  相似文献   
28.

Purpose

Pinch-off syndrome (POS) is a serious complication encountered during the long-term management of totally implantable access ports (TIAPs). The aim of this study was to examine the effect of ultrasound-guided infraclavicular axillary vein puncture to avoid POS in patients with long-term use of a TIAP.

Methods

This was a retrospective review of 207 consecutive TIAPs: one hundred devices implanted using an anatomical landmark technique were used as historical controls (Landmark group), while 107 devices were implanted using an ultrasound (US)-guided puncture method (US group). The pinch-off grade (POG) was determined using chest X-ray findings following the definition of Hinke, and the progression of POG during the follow-up period of the Landmark and US groups was compared.

Results

Sixteen cases in the Landmark group were POG-1 and 3 were POG-2, while all cases in the US group were POG-0 at the time of venipuncture (p < 0.001). Eleven patients in the Landmark group showed some degree of progression of the POG during the follow-up period. In contrast, there were no cases showing progression of the POG in the US group (p = 0.002).

Conclusions

US-guided infraclavicular axillary vein puncture was found to effectively make it possible to avoid POS for the long-term management of TIAPs, as well as at the time of implantation.  相似文献   
29.
We experienced a rare case of endotracheal metastasis derived from squamous cell lung cancer. The patient was 56 year-old male whose primary lung cancer of the left upper lobe was completely resected. Pathological diagnosis indicated stage IIB and he underwent two cycles of chemotherapy with CDDP + VDS. He had been asymptomatic thereafter, however, two years postoperative chest CT revealed a nodular lesion of the anterior carinal wall. Bronchofiberoptic examination showed same as CT finding and its brushing cytology confirmed squamous cell carcinoma. WE successfully resected his endotracheal metastatic lesion and reconstructed by direct sutures assisted by PCPS (Percutaneous Cardiopulmonary Support System). His postoperative course was uneventful. Majority of the reported cases of endotracheal metastases were treated conservatively as radiation, laser and/or chemotherapy. We conclude that PCPS is useful device for surgical management for selected cases.  相似文献   
30.
From January 1975 to December 1986, 415 patients were operated for primary lung cancer. Postoperative pulmonary complications were observed in 83 patients and among them 48 patients (57.8%) suffered from difficulty in expectoration. Postoperative expectoration mostly depends on the ability of coughing. To evaluate cough dynamics, expiratory flow-rate and volume at voluntary maximal cough were measured. The more expiratory flow rate and volume a cough has, the more effective it is for expectoration. In those patients with decreased FEV1.0, or respiratory muscle weakness because of emaciation and aging, or severe pain in the wound, the cough dynamics was decreased. By cleaning retained secretions in the respiratory tract, postoperative pulmonary complications would be prevented. However in cases where the decrease in postoperative cough dynamics is predictable, application of limited resection should be considered as well.  相似文献   
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