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Summary Purpose Although end-to-side anastomosis is an essential method for the transfer of free flaps in traumatic extremity injuries, orthoplastic surgeons have no standard technique for performing this procedure. We describe a simple and reliable end-to-side technique is modified from that commonly used by cardiovascular surgeons for free-flap transfer. Methods Our microscopic parachute end-to-side technique consists primarily of two simple steps. First, the donor vessel is cut and widened with microscissors, and a wide slit is made in the recipient vessel. Second, the heel of the vessel is sutured using the parachute technique, followed by suturing of the vessel wall with a continuous suture to control blood leakage from the widely opened window. We retrospectively evaluated the clinical outcomes of 18 flaps in which the microscopic parachute end-to-side technique was used for both arterial and venous anastomoses. Results All microscopic parachute end-to-side procedures achieved flap survival without complications related to anastomosis. The mean size of the vesselotomy was 4.8 mm, and the mean expansion rate of the donor vessel was 2.7 times. Conclusions Compared with the conventional end-to-side technique, the microscopic parachute end-to-side technique has three advantages: easy vesselotomy, avoidance of anastomotic narrowing, and easy control of blood leakage from the anastomotic site. We believe that the microscopic parachute end-to-side technique might make free flaps easier and improve their clinical outcomes in severe extremity injuries.

To evaluate embolization efficacy of pulmonary arteriovenous malformations (PAVM) using Amplatzer vascular plugs (AVP) and coils. Eighty-eight embolized simple PAVMs in 38 patients were retrospectively analyzed by follow-up CT. Mean age was 50.2 ± 15.6 years and 22 (57.9%) patients were females. Mean follow-up interval was 38.2 ± 28.4 months (median 29.9 months). Embolization devices included AVP I, AVP II, AVP 4, and coils. Technical success was defined as no visualization of an early draining vein at angiography after embolization. Treatment success was defined as complete disappearance or decrease in size of the venous aneurysm ≥ 70% at follow-up CT. Technical success rate was 100% and treatment success rate evaluated by CT for the various embolization strategies was 100% for AVP I (n = 6), 100% for AVP I + coils (n = 5), 83.3% for AVP II (n = 6), 40.0% for AVP II + coils (n = 5), 87.5% for AVP 4 (n = 8), 50.0% for AVP 4 + coils (n = 8), and 78.0% for coils alone (n = 50). No statistically significant difference in embolization efficacy was seen between different devices (P = 0.083). Although not statistically significant, combination use of coils with AVPs demonstrated lower rates of clinical embolization success (P = 0.053). Embolization of PAVMs demonstrated high technical and treatment success rates with available embolic devices. No significant statistical differences were demonstrated between AVPs. However, the need for both coils and AVPs may suggest a more complicated underlying lesion at risk for recurrence.

Made available in DSpace on 2020-12-12T02:37:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-07-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Floral fragrances play an important role in pollinator attraction; they serve as signals for primary rewards such as nectar. The presence of osmophores (a specialized glandular tissue that produces fragrance) in the terrestrial orchid Cyclopogon has only been described in a single species. There are fragrant and odorless species within this genus, but no data on the similarities or differences between them has been published. Here, we present new data on the lip morphology and ultrastructure from eight Cyclopogon species to better understand the mechanisms of pollinator attraction of this group. To achieve this goal, we used light, scanning, and transmission electron microscopy. Five out of eight species presented globular trichomes associated with fragrance production on the abaxial side of the labellum. Together with subepidermal cells, they compose the secretory tissue. Despite the absence of globular trichomes, C. apricus also presented cells associated with fragrance production. Lipid droplets, plastids containing plastoglobuli, and starch were indicators of secretory activity present in these species. This same pattern of fragrance production and release, associated with flower morphology, may result in the restriction of pollination by halictid bees. Institute of Biosciences Department of Botany São Paulo State University – UNESP Institute of Biosciences Department of Botany São Paulo State University – UNESP CNPq: 304396/2015-0 CAPES: 88882.317776/2019-01

[Background] Left subclavian artery (LSA) embolization is occasionally required to prevent type II endoleak in the thoracic endovascular aortic repair (TEVAR) procedure. This is a retrospective study comparing compressed Amplatzer Vascular Plug II embolization (CAE) and conventional coil embolization (CCE) in preventing retrograde flow into the aneurysmal sac through the LSA after TEVAR. [Methods] We retrospectively reviewed the records of patients who underwent CAE or CCE of the LSA during TEVAR from June 2013 to March 2016 in our hospital. The efficacy, safety and cost of each method were compared between two groups. [Results] Thirty patients underwent LSA embolization during TEVAR. Six CCEs in 6 patients were performed from June 2013 to November 2013, while twenty-four CAEs in 24 patients were performed from December 2013 to March 2016. Technical success was achieved in all patients in both groups. No embolization-related complications or type II endoleaks from LSA were recorded during the follow-up period in all patients. In both groups, all embolic materials were detected in the proximal portion of the LSA from the LSA orifice to the vertebral artery origin and no vertebral artery occlusions were detected. The mean compression ratio of AVP II was 58 ± 5.9% of predicted length of standard procedure. In the CAE group, one AVP II was sufficient to achieve complete LSA occlusion in all patients. On the other hand, multiple coils (10.2 ± 2.7) were used in the CCE group (P < .01), resulting in a significantly lower cost incurred in the CAE group (CAE: 129,000 JPY vs. CCE: 639,600 ± 140,060 JPY; P < .01). [Conclusion] The CAE is a useful and cost-effective procedure for TEVAR-related LSA embolization.

Background Bile leakage after hepatectomy is a common complication. The purpose of the present study was to retrospectively evaluate the usefulness of non-surgical management of bile leakage after hepatectomy, using 12-year data from a single center study. Methods Data from 15 patients (13 men, two women; mean age 67.1 ± 7.0 years) who had undergone non-surgical management for bile leakage between January 2005 and November 2017 were retrospectively reviewed. Results We categorized bile leakage as central (n = 5) or peripheral (n = 10) leakage based on communication with the biliary tree. Percutaneous bile leakage drainage and/or endoscopic naso-biliary drainage (ENBD) (n = 2) or the rendezvous technique (n = 3) was successfully performed in five central-type cases, while all peripheral-type cases were treated with drainage alone; only one case required additional ethanol ablation. Bacterial bile cultures were positive in 11 cases and negative in four cases. The drainage catheters were removed after complete resolution in 13 cases (86.7%), while two patients with cases of peripheral-type leakage died due to cancer progression while the drain was in place. No case needed conversion to reoperation. The mean duration of drainage therapy in all cases was 210.1 ± 163.0 days (range 17-531 days), with 316.8 ± 180.8 days in the central type and 156.7 ± 131.5 days in the peripheral type; this duration was not significantly different (P = 0.129). Conclusion Non-surgical treatment is a minimally invasive and effective management strategy for postoperative bile leakage and the modality used depends on the type of bile leakage encountered.

Numerous noncoding RNA transcripts are detected in eukaryotic cells. Noncoding RNAs transcribed across gene promoters are involved in the regulation of mRNA transcription via chromatin modulation. This function of noncoding RNA transcription was first demonstrated for the fission yeast fbp1 gene, where a cascade of noncoding RNA transcription events induces chromatin remodeling to facilitate transcription factor binding. We recently demonstrated that the noncoding RNAs from the fbp1 upstream region facilitate binding of the transcription activator Atf1 and thereby promote histone acetylation. Histone acetylation by histone acetyl transferases (HATs) and ATP-dependent chromatin remodelers (ADCRs) are implicated in chromatin remodeling, but the interplay between HATs and ADCRs in this process has not been fully elucidated. Here, we examine the roles played by two distinct ADCRs, Snf22 and Hrp3, and by the HAT Gcn5 in the transcriptional activation of fbp1. Snf22 and Hrp3 redundantly promote disassembly of chromatin in the fbp1 upstream region. Gcn5 critically contributes to nucleosome eviction in the absence of either Snf22 or Hrp3, presumably by recruiting Hrp3 in snf22∆ cells and Snf22 in hrp3∆ cells. Conversely, Gcn5-dependent histone H3 acetylation is impaired in snf22∆/hrp3∆ cells, suggesting that both redundant ADCRs induce recruitment of Gcn5 to the chromatin array in the fbp1 upstream region. These results reveal a previously unappreciated interplay between ADCRs and histone acetylation in which histone acetylation facilitates recruitment of ADCRs, while ADCRs are required for histone acetylation.

Transcription factors (TFs) determine the transcription activity of target genes and play a central role in controlling the transcription in response to various environmental stresses. Three dimensional genome structures such as local loops play a fundamental role in the regulation of transcription, although the link between such structures and the regulation of TF binding to cis-regulatory elements remains to be elucidated. Here, we show that during transcriptional activation of the fission yeast fbp1 gene, binding of Rst2 (a critical C2H2 zinc-finger TF) is mediated by a local loop structure. During fbp1 activation, Rst2 is first recruited to upstream-activating sequence 1 (UAS1), then it subsequently binds to UAS2 (a critical cis-regulatory site located approximately 600 base pairs downstream of UAS1) through a loop structure that brings UAS1 and UAS2 into spatially close proximity. Tup11/12 (the Tup-family corepressors) suppress direct binding of Rst2 to UAS2, but this suppression is counteracted by the recruitment of Rst2 at UAS1 and following delivery to UAS2 through a loop structure. These data demonstrate a previously unappreciated mechanism for the recruitment and expansion of TF-DNA interactions within a promoter mediated by local three-dimensional genome structures and for timely TF-binding via counteractive regulation by the Tup-family corepressors.

To evaluate embolization efficacy of pulmonary arteriovenous malformations (PAVM) using Amplatzer vascular plugs (AVP) and coils.Eighty-eight embolized simple PAVMs in 38 patients were retrospectively analyzed by follow-up CT. Mean age was 50.2 ± 15.6 years and 22 (57.9%) patients were females. Mean follow-up interval was 38.2 ± 28.4 months (median 29.9 months). Embolization devices included AVP I, AVP II, AVP 4, and coils. Technical success was defined as no visualization of an early draining vein at angiography after embolization. Treatment success was defined as complete disappearance or decrease in size of the venous aneurysm ≥ 70% at follow-up CT.Technical success rate was 100% and treatment success rate evaluated by CT for the various embolization strategies was 100% for AVP I (n = 6), 100% for AVP I + coils (n = 5), 83.3% for AVP II (n = 6), 40.0% for AVP II + coils (n = 5), 87.5% for AVP 4 (n = 8), 50.0% for AVP 4 + coils (n = 8), and 78.0% for coils alone (n = 50). No statistically significant difference in embolization efficacy was seen between different devices (P = 0.083). Although not statistically significant, combination use of coils with AVPs demonstrated lower rates of clinical embolization success (P = 0.053).Embolization of PAVMs demonstrated high technical and treatment success rates with available embolic devices. No significant statistical differences were demonstrated between AVPs. However, the need for both coils and AVPs may suggest a more complicated underlying lesion at risk for recurrence.

Purpose: To evaluate the effect of vessel calcification on in-stent restenosis (ISR) after drug-coated stent (DCS) placement in the femoropopliteal segment. Materials and Methods: A retrospective multicenter study was undertaken involving 220 consecutive symptomatic patients (mean age 73.1±8.3 years; 175 men) with femoropopliteal lesions in 230 limbs treated with the Zilver PTX DCS and having duplex surveillance after the endovascular procedures. Mean lesion length was 16.4±9.8 cm (range 2–40); there were 104 (45.2%) total occlusions and 68 (29.6%) in-stent restenoses (ISR). Twenty (8.7%) vessels had no runoff. The majority of lesions (148, 64.3%) were calcified according to the peripheral arterial calcium scoring system (PACSS). Primary patency was evaluated by duplex. Lesions were classified as either PACSS 0–2 (none or unilateral wall calcification) or PACSS 3 and 4 (bilateral wall calcification). Multivariate analysis was performed to identify variables associated with ISR; the results are given as the hazard ratio (HR) and 95% confidence interval (CI). Results: The 1-, 2-, and 5-year primary patency and freedom from clinically-driven target lesion revascularization estimates were 75.9%, 63.6%, and 45.0%, and 84.7%, 73.7%, and 54.2%, respectively. Major amputations were performed on 4 limbs during follow-up. In multivariate analysis, vessel calcification (adjusted HR 1.718, 95% CI 1.035 to 2.851, p=0.036) was significantly correlated with the occurrence of ISR, along with lesion length (adjusted HR 1.041, 95% CI 1.013 to 1.070, p=0.003), and cilostazol administration (adjusted HR 0.476, 95% CI 0.259 to 0.876, p=0.017). Conclusion: This study suggested that bilateral vessel wall calcification was an independent risk factor for ISR in complex femoropopliteal lesions after Zilver PTX DCS placement, along with lesion length; cilostazol administration had a protective effect.

Flavonoids are a class of distinct compounds produced by plant secondary metabolism that inhibit or promote plant development and have a relationship with auxin transport. We showed that, in terms of root development, Copaifera langsdorffii leaf extracts has an inhibitory effect on most flavonoid components compared with the application of exogenous flavonoids (glycosides and aglycones). These compounds alter the pattern of expression of the SHORT-ROOT and HD-ZIP III transcription factor gene family and cause morpho-physiological alterations in sorghum roots. In addition, to examine the flavonoid auxin interaction in stress, we correlated the responses with the effects of exogenous application of auxin and an auxin transport inhibitor. The results show that exogenous flavonoids inhibit primary root growth and increase the development of lateral roots. Exogenous flavonoids also change the pattern of expression of specific genes associated with root tissue differentiation. These findings indicate that flavonoid glycosides can influence the polar transport of auxin, leading to stress responses that depend on auxin.

Purpose To evaluate dose-response relationship in yttrium-90 ( 90 Y) resin microsphere radioembolization for neuroendocrine tumor (NET) liver metastases using a tumor-specific dose estimation based on technetium-99m–labeled macroaggregated albumin ( 99m Tc MAA) single photon emission computed tomography (SPECT)-CT. Materials and Methods Fifty-five tumors (mean size 3.9 cm) in 15 patients (10 women; mean age 57 y) were evaluated. Tumor-specific absorbed dose was estimated using a partition model. Initial (median 2.3 months) follow-up data were available for all tumors; last (median 7.6 months) follow-up data were available for 45 tumors. Tumor response was evaluated using Modified Response Evaluation Criteria in Solid Tumors (mRECIST) on follow-up CT. Tumors with complete or partial response were considered responders. Mean tumor absorbed dose was 231.4 Gy ± 184.3, and mean nontumor liver absorbed dose was 39.0 Gy ± 18.0. Results Thirty-six (65.5%) and 30 (66.7%) tumors showed response at initial and last follow-up, respectively. Mean absorbed doses in responders and nonresponders at initial and last follow-up were 285.8 Gy ± 191.1 and 128.1 Gy ± 117.1 ( P = .0004) and 314.3 Gy ± 195.8 and 115.7 Gy ± 117.4 ( P = .0001). Cutoff value of ≥ 191.3 Gy for tumor-specific absorbed dose predicted tumor response with 93% specificity, whereas P = .007). Conclusions Tumor-specific absorbed dose, estimated with a partition model, was significantly associated with tumor response in NET liver metastases. An estimated dose ≥ 191.3 Gy predicted treatment response with high sensitivity and specificity.

Purpose To evaluate the safety and efficacy of coil embolization with an indwelling catheter with side holes to control visceral artery bleeding while simultaneously preserving peripheral artery flow. Materials and Methods A 6-F anticoagulant-coated catheter with two symmetrically arranged side holes was used with coil embolization to induce hemostasis in the superior mesenteric artery (SMA) of 13 pigs. The SMA was punctured with a metal needle to induce bleeding. The catheter was advanced into the SMA immediately after the puncture, and the midpoint between its tip and side holes was adjusted to conform to the puncture site. The SMA was embolized by using microcoils placed around the catheter to achieve hemostasis. Hemostasis and gross ischemic changes of the intestine were visually observed during the abdominal surgery. Peripheral blood flow was assessed by using abdominal aortography for as long as 2 hours in 13 pigs and was assessed again at 7 days in three pigs. Results Antegrade peripheral artery flow through the indwelling catheter was preserved without stagnation for as long as 2 hours in all 13 pigs and at 7 days in two of three pigs. One catheter occlusion was seen at the 7-day time point. There were no observable instances of recurrent bleeding, ischemic changes in the intestine, or vascular adverse events during or after the procedure. Conclusions The hemostatic method described here is a technically feasible method of controlling acute visceral artery bleeding while preserving peripheral artery flow and may be particularly useful in cases of absence of collateral circulation. Further experiments are warranted for clinical application.

Aims and Objectives: Ethanol is widely used for the embolization treatment of vascular malformations, but it can also cause serious complications such us pulmonary hypertension, cardiopulmonary collapse and death. The complications are considered secondary to pulmonary vasospasm and ethanol-induced sludge embolism, etc., We studied the hemodynamic effects of intravenous absolute ethanol injection and ethanol sludge injection in pigs. Materials and Methods: A total of 5 pigs underwent intravenous injection of ex vivo generated ethanol-induced sludge in which residual ethanol was removed (Group S) and 4 pigs underwent intravenous injection of absolute ethanol (Group E). Hemodynamic parameters related to the pulmonary and systemic circulation were compared between the groups. Results: Transient pulmonary hypertension was observed in both groups and the hemodynamic changes were similar in both groups. Conclusions: Sludge can induce transient pulmonary hypertension or cardiopulmonary collapse, without ethanol and may be the mechanism by which ethanol induces its adverse hemodynamic effects.

To prevent pulmonary embolism due to deep venous thrombosis (DVT), we have treated 611 patients undergoing orthopedic surgery of the lower extremities with our protocol including pre- and postoperative ultrasonic venous screening and anticoagulant therapy if necessary. A total of 118 patients (19.3%) developed DVT. Among demographic and clinical factors, the site of operation (knee joint surgery: odds ratio 5.17), age (>60: odds ratio 3.91), and operation time (>120 minutes: odds ratio 4.52) were identified as significant risk factors of development of DVT. One patient received an infusion of urokinase for DVT of femoral vein, but no patients developed serious postoperative bleeding or pulmonary thromboembolisms. (*English Translation of J Jpn Coll Angiol, 2010, 50: 95-100.).

Covered, self-expandable metallic stents (SEMS) have been enthusiastically adopted for the treatment of esophagotracheal fistula, but problems with stent migration have yet to be resolved. To overcome this problem, we have developed a new hanging-type esophageal stent designed to prevent migration, and we conducted an animal study to assess the efficacy of our method.A total of six female pigs were used in this study. The main characteristic of our stent was the presence of a string tied to the proximal edge of the stent for fixation under the skin of the neck. The first experiment was performed to confirm technical feasibility in three pigs with esophagotracheal fistula. The second experiment was performed to evaluate stent migration and esophagotracheal fistula in three pigs.Creation of the esophagotracheal fistula and stent placement were technically successful in all pigs. In the first experiment, esophagotracheal fistula was sealed by stent placement. In the second experiment, no stent migration was seen 11 or 12 days after stent placement. Gross findings showed no fistulas on the esophageal or tracheal wall.Our new hanging-type esophageal stent seems to offer a feasible method for preventing stent migration.

To prospectively evaluate the safety of radiofrequency (RF) ablation for vertebral lesions by monitoring the temperature in swine vertebral models with and without a cortical bone defect.The institutional animal care and use committee approved the animal studies. In vivo and ex vivo studies were performed. In the in vivo study, 20 lumbar vertebrae from six swine were locally heated by using 1- or 2-cm active-tip internally cooled electrodes. In the ex vivo study, 12 fresh pig cadaver lumbar vertebrae were extracted from four swine, and spinal tumor models with or without cortical bone defect were created by stuffing a cavity with muscle tissue and locally heated by using a 1-cm active-tip internally cooled electrode. The temperature was monitored in the spinal canal and around the vertebral body during ablation. Mann-Whitney U test was used to indicate a significant difference between groups by using 1- and 2-cm active tip in the in vivo study and between groups with and without cortical defect in the ex vivo study.In the in vivo study in which 1- and 2-cm active-tip needles were used, the temperature in the spinal canal rose to 38.2 degrees C +/- 2.7 (standard deviation) and 45.5 degrees C +/- 6.2, respectively. The latter was significantly higher than the former (P.001). In the ex vivo study in which tumor models with or without a cortical bone defect were used, the temperature in the spinal canal rose to 48.4 degrees C +/- 6.2 and 31.3 degrees C +/- 3.4, respectively. The former was significantly higher than the latter (P.001).For in vivo cases with a 2-cm active tip and ex vivo cases with a vertebral posterior bone defect, the temperature rose to over 45 degrees C, potentially injuring the spinal cord and peripheral nerves.

For the improvement of a surface wear resistance of aluminum alloys, iron-based alloys were clad on the surface of an aluminum alloy by laser. By investigating the effect of CO2 and diode laser irradiation conditions on the formability of Fe-Cr-C clad layers, it was confirmed that the application of diode laser made it possible to obtain stable beads in low heat input compared with CO2 laser, which has been conventionally used for laser cladding. Besides, by optimizing the laser parameters, the dilution ratio of clad layers by Al substrate was minimized less than 10%. At the clad interface, the reaction layer consisting of Fe2Al5 and FeAl3 formed which caused cracks at the clad interface. Even by controlling laser conditions, this brittle layer formation could not suppressed. In this research, by using the immiscible Fe-Cu-Cr alloys as clad materials, Fe based clad layers were formed on Al substrate without any cracks at clad interface. By the effect of Marangoni motion of decomposed duplex liquid phases, Cu segregated between Al substrate and Fe based clad layers and suppressed the reaction between them.

テキストを意味段落に分割する方法として, 語の反復距離に基づく話題結束度による認定手法を提案する. 意味段落とはテキスト中に含まれるまとまった話題の単位である. 文をまたがって出現する反復語の文間距離をもとに話題形成の尺度化を行い話題結束力を算出する. 語が近接して反復する区間に話題形成ポテンシャルが生じ, それが話題結束力を形成するという話題境界判定モデルを考案した. 社説記事を連結して, 記事境界と段落分割点とが一致したときを正解とする境界判定実験を行った結果, 再現率67.8%, 適合率61.8%の精度を得た. 極めて簡単な方法で段落境界を判定することができ, 記事以外に随筆等の比較的長いテキストに対しても有効である.

Disilane unit-fused poly(diphenylamine) (poly(10,11-dihydro-10,11-disila-5,10,10,11,11-pentamethyl-5H-dibenz[b,f]azepine-2,8-diyl), PDSiAzep) were prepared and properties of these compounds were studied. Oxidation of PDSiAzep led to related disiloxane-fused poly(diphenylamine) (poly(5,7-disila-6-oxa-5,5,7,7,12-pentamethyl-5,6,7,12-tetrahydrodibenz[b,g]azocine-3,9-diyl) PSiO). These polymers have new heterocyclic unit. Not only UV and Cyclic voltammetry (CV) measurements but also X-ray crystallography of the related dibromide suggested that the structure of the bridging unit affected π-conjugation through the N atom. The highest conductivities of electrochemically doped PDSiAzep and PSiO were 2.0 x 10 -4 and 1.3 × 10 -2 , respectively. Turn-on bias voltage of a double layer electroluminescent device comprising PDSiAzep was higher than that of PSiO. These electrical properties were depended on effective π-conjugation through the N atom.

Although surgery is the usual management strategy for acquired benign tracheoesophageal fistula, sometimes this approach is contraindicated or the patient declines surgical management. In this report, we describe a case of a patient with tracheoesophageal fistula at the level of the carina due to bronchial arterial infusion chemotherapy. Closure could not be achieved in response to multiple treatment strategies, including airway stenting, esophageal stenting, occlusion with microcoils, or cyanoacrylate glue. We subsequently achieved closure of this fistula through the combination of a modified silicon stent and metallic stents.

Compounds having two bithiophene units linked by an organosilicon bridge were prepared. Their UV spectra and cyclic voltammograms indicated that the compounds have the low-lying LUMO. The electron transporting properties of the present silicon-bridged bithiophene derivatives were evaluated by the performance of electroluminescent (EL) devices having vapor deposited silicon-bridged bithiophenes, Alq, and TPD layers, as the electron-transport, emitter and hole-transport, respectively. By applying the bias voltage on the devices, the devices emitted green EL originated from the Alq emission with the maximum luminance of 8500 cd m−2.

Dithienosiloles (DTSs) bearing conjugated aryl substituents on the thiophene rings (1 and 2) were prepared and their optical, electrochemical, and electron-transporting properties were investigated in comparison with those of simple DTSs having no conjugated substituents on the thiophene rings (4−6). UV absorption bands of 1 and 2 are red shifted from those of 4−6 by 40−80 nm, reflecting the expanded π-conjugation, whereas the first oxidation peaks in the cyclic voltammograms of 1 and 2 appear at potentials a little lower or almost the same energies relative to those of 4−6, depending on the nature of the substituents. The electron-transporting properties of 1 and 2 were evaluated by the performance of electroluminescent (EL) devices having vapor-deposited DTS, Alq, and TPD layers, as the electron-transport, emitter, and hole-transport, respectively. The results indicated that introduction of aryl substituents to DTSs led to inferior performance of the devices in most cases, while the device with 1c beari...

We have synthesized novel σ–π conjugated polymers with an alternating organosilanylene and π-electron system, intending to utilize them for hole-transporting materials of electroluminescent (EL) devices. 3,6-Di(lithioethynyl)carbazoles were co-polymerized with organodichlorosilanes to give the corresponding polymers with molecular weights of MW = 2000–5000. Another type of polymer with a thienylene unit was also synthesized by the nickel-catalyzed reaction of the di-Grignard reagent of 1,2-bis[2-(5-bromothienyl)]tetraethyldisilane with 3,6-dibromocarbazole, the molecular weight being Mn = 3100. The EL devices with a double-layer system composed of tris(8-quinolinolato)aluminum(III) and the present polymers as the emitting-electron-transporting and hole-transporting layers, respectively, emit green EL with a maximum intensity of the order of 103 cd m−2. Of these, the device with the thienylene–carbazole polymers exhibited the highest luminance of 1480 cd m−2. Copyright © 2001 John Wiley & Sons, Ltd.

We have synthesized novel σ–π conjugated polymers with N,N-bis(p-ethynylphenyl)-N-(p-tolyl)amine as the π-unit. The electroluminescent devices, with a double-layer system composed of Alq and the present polymers as the emitting-electron-transporting and hole-transporting layers respectively, emit green electroluminescence with a maximum intensity of 760 cd m−2. Copyright © 2001 John Wiley & Sons, Ltd.

1,8-(Di-sec-butylsilano)-, 1,8-{bis[(trimethylsilyl)methyl]silano}-, and 1,8-{bis[(S)-2-methylbutyl]silano}naphthalene (1a−c) were prepared, and their ring-opening reactions were investigated. Reactions of 1a,b with methyllithium afforded products arising from the addition of methyllithium to the Si−C bond of the four-membered ring of 1a,b, followed by rearrangement of the resulting anionic species. Methanolysis of 1a gave 1-(methoxydi-sec-butylsilyl)naphthalene. Heating 1a,b in the presence of a catalytic amount of Pd(PPh3)4 gave the head-to-tail cyclic dimers. Treatment of 1a,c with lithium metal gave ring-opened oligo(silylene-1,8-naphthylenes) in good yield. The optical data of the oligomers indicated the existence of helical structural segments in the backbone. The hole-transporting properties of the oligomer obtained from 1a were examined by the performance of an EL device with the strcture of ITO/oligo(silylene-1,8-naphthylene)/Alq/Mg−Ag, which emitted green luminescence due to the Alq emission. Th...

Polymers with alternating mono-, di-, or trisilanylene units and 2,5-oligothienylene groups, [(SiR2)x(C4H2S)m]n (R = Me, Et, x = 1−3, m = 2−5), were synthesized and their optical, conducting, and hole-transporting properties were investigated. The UV absorption and emission maxima of the polymers shift to lower energies as the number of thienylene groups (m) between the silanylene units increases, while they are little affected by the silicon chain length (x). When the polymer films were exposed to FeCl3 vapor, semiconducting films with the conductivities of 1.3 × 10-4−2.3 × 10-1 S/cm were obtained. The conductivities tend to increase with m but decrease with increasing x. The double-layer-type EL devices were fabricated using some of the polymers (x = 1, m = 3−5; x = 2, m = 4) as the hole-transporting layer and tris(8-quinolinolato)aluminum(III) (Alq) as the electron-transporting-emitter layer. Reducing the number of m and x resulted in a high-voltage shift in the turn-on voltage and a decrease in the ma...

Patch-clamp recordings were used to examine the osmosensitivity and mechanosensitivity of neurons in the caudal part of the nucleus tractus solitarius in coronal slices from rat brain. Firing rates and membrane potentials were measured as slices were exposed to perfusate which varied in its osmolality and/or sodium concentration. In all cells tested, the responses to change in the sodium concentration of perfusate were duplicated by osmolality changes of sucrose or mannitol. When nucleus tractus solitarius cells were tested with changes in pressure applied via the pipette, responses to positive or negative pressure paralleled their responses to osmotic stimulation. We suggest that a mechanosensitive receptor exists on osmosensitive neurons within the nucleus tractus solitarius, and this receptor may be responsible for changes in the firing rate and membrane potential which occur in the nucleus tractus solitarius neurons.

Nickel-complex-catalyzed dehalogenative coupling of diGrignard reagents prepared from bis(bromoaryl)disilanes or monosilane with 2,6-dibromodithienosiloles afforded the corresponding polymers composed of alternating 2,6-diaryldithienosilole and organosilicon units. These polymers exhibit strong UV-vis absorption and emission bands at 422–444 and 482–541 nm, respectively. Their cyclic voltammograms display the first oxidation peaks at 0.95–1.00 V vs. SCE (saturated Calomel electrode). When the polymer films were doped with FeCl3 vapor, the films became conducting, and their conductivities were determined to be 3.3×10–5 – 8.7×10–3 S/cm using the four probe method. Electron- and hole-transporting properties of the polymers were also studied by evaluating the performance of electroluminescent (EL) devices based on these polymers.

Coupling reactions of 9,10-di(lithioethynyl)anthracene with dichloromono-, di-, and trisilanes, Cl(SiR2)mCl (m=1–3) gave polymers composed of alternating 9,10-diethynylanthracene and organosilicon units. With dichlorotetraorganodisilanes, the corresponding dianthracenophanes composed of two 9,10-diethynylanthracene units linked by tetraorganodisilanylene bridges were also obtained, together with the polymers. The emission spectra of the polymers with di- and trisilanylene units suggest that intrachain aggregation takes place in solution, although it is not obvious for the silanylene polymer. Cyclic voltammetric (CV) analysis of the polymers shows the evident dependence of the CV profiles on the lengths of the silicon chain between the diethynylanthracene units. When the polymer films were treated with FeCl3 vapor, the films became conducting with the maximum conductivities in the order of 10−5 S cm−1. The double-layer-type electroluminescent (EL) devices were fabricated using these polymers as a hole-transporting layer and tris(8-quinolinolato)aluminum (III) complex (Alq) as an electron-transporting-emitter layer. The turn-on voltage of the devices became higher and the maximum current density smaller, as increasing the number of silicon atoms in a polymer unit from m=1 to 3. The highest luminance of 1300 cd m−2 was obtained from the device based on the silanylene-diethynylanthracene polymer.