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1.
Br J Surg ; 108(11): 1315-1322, 2021 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-34467970

RESUMO

BACKGROUND: There is a lack of information regarding the provision of parental leave for surgical careers. This survey study aims to evaluate the experience of maternity/paternity leave and views on work-life balance globally. METHODS: A 55-item online survey in 24 languages was distributed via social media as per CHERRIES guideline from February to March 2020. It explored parental leave entitlements, attitude towards leave taking, financial impact, time spent with children and compatibility of parenthood with surgical career. RESULTS: Of the 1393 (male : female, 514 : 829) respondents from 65 countries, there were 479 medical students, 349 surgical trainees and 513 consultants. Consultants had less than the recommended duration of maternity leave (43.8 versus 29.1 per cent), no paid maternity (8.3 versus 3.2 per cent) or paternity leave (19.3 versus 11.0 per cent) compared with trainees. Females were less likely to have children than males (36.8 versus 45.6 per cent, P = 0.010) and were more often told surgery is incompatible with parenthood (80.2 versus 59.5 per cent, P < 0.001). Males spent less than 20 per cent of their salary on childcare and fewer than 30 hours/week with their children. More than half (59.2 per cent) of medical students did not believe a surgical career allowed work-life balance. CONCLUSION: Surgeons across the globe had inadequate parental leave. Significant gender disparity was seen in multiple aspects.


Assuntos
Escolha da Profissão , Internato e Residência/estatística & dados numéricos , Licença Parental/estatística & dados numéricos , Estudantes de Medicina/estatística & dados numéricos , Cirurgiões/estatística & dados numéricos , Inquéritos e Questionários , Adulto , Atitude do Pessoal de Saúde , Feminino , Humanos , Masculino , Fatores Sexuais , Adulto Jovem
2.
Tech Coloproctol ; 25(2): 223-227, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33459968

RESUMO

BACKGROUND: Complete mesocolic excision with central vessel ligation may be important for accurate staging and improving the prognosis of right-sided colon cancer. Although the procedure is often performed laparoscopically, approaching the middle colic artery (MCA) is technically demanding, especially when complete ligation of arteries at their roots is desired. We standardized our laparoscopic approach by establishing the dissection boundary along the superior mesenteric artery to achieve D3 lymphadenectomy in the region of the MCA. The aim of the present study was to evaluate, on the basis of perioperative and short-term oncologic outcomes, the feasibility and safety of our technique METHODS: We conducted a retrospective study on consecutive patients with cancer located at the ascending colon and transverse colon who had laparoscopic right hemicolectomy requiring ligation of the MCA. RESULTS: There were 41 patients (22 males, median age 71 years [range 49-86] years). The median operation time was 285 min, and blood loss volume was 40 mL. Conversion to open surgery was required in 1 case. Complications that were Clavien-Dindo grade III or above occurred in 3 patients (7.3%). There was no anastomotic leakage. The median number of lymph nodes harvested was 46. CONCLUSIONS: Our technique was shown to be a safe, feasible, and useful strategy for performance of right hemicolectomy requiring ligation of the MCA in cases of colon cancer. The technique facilitates maximal lymph node dissection. Having obtained favorable outcomes, we look forward to investigation into long-term outcomes.


Assuntos
Neoplasias do Colo , Laparoscopia , Mesocolo , Idoso , Idoso de 80 Anos ou mais , Colectomia , Neoplasias do Colo/cirurgia , Humanos , Ligadura , Excisão de Linfonodo , Masculino , Artéria Mesentérica Inferior/cirurgia , Artéria Mesentérica Superior , Mesocolo/cirurgia , Pessoa de Meia-Idade , Estudos Retrospectivos
4.
J Appl Microbiol ; 127(6): 1869-1875, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31461201

RESUMO

AIMS: Given the significance of Salmonella enterica in both human and animal health, and a recent global dissemination of Salmonella 4,[5],12:i:-, changes in the prevalent serovars and antimicrobial resistance in clinical isolates of Salmonella from cattle and pigs were investigated in Japan. METHODS AND RESULTS: The serovars and antimicrobial susceptibilities of 1605 Salmonella enterica isolated from cattle (n = 894) and swine (n = 711) between 2002 and 2016 were examined. The most common serovar among all samples was Salmonella Typhimurium. However, its monophasic variant with antigenic structure S. 4,[5],12:i:-, which was first detected in cattle in 2006 and swine in 2010, has been rapidly increasing in incidence and resistance. Resistance rates to cefotaxime and ciprofloxacin were generally low (<10% in the cattle isolates and <5% in the swine isolates); however, isolates resistant to more than five antimicrobials, which often include these antimicrobials, were recently detected in Salmonella Dublin, S. 4,[5],12:i:-, S. Typhimurium, Salmonella Newport, Salmonella Choleraesuis and Salmonella 6,7:c:-. Among them, two S. 4,[5],12:i:- isolates possessed extended-spectrum ß-lactamase-encoding genes; blaSHV-12 or blaCTX-M-55 , respectively, while all the five S. Typhimurium isolates possessed AmpC-type ß-lactamase gene of blaCMY-2 . CONCLUSIONS: S. 4,[5],12:i:- has been rapidly increasing and exhibiting a remarkable change in antimicrobial resistance in Japan. Considering certain serovars are characterized by multidrug resistance including medically important antimicrobials, continuous monitoring and appropriate measures are required to protect public health and veterinary husbandry. SIGNIFICANCE AND IMPACT OF THE STUDY: This study presents a trend in the serovars and antimicrobial resistance in clinical isolates of Salmonella from cattle and pigs in Japan, and showed that there were certain types of Salmonella serovars depending on the animal origin which needs more attention.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Salmonelose Animal/microbiologia , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/genética , Animais , Bovinos , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Japão/epidemiologia , Testes de Sensibilidade Microbiana , Salmonelose Animal/epidemiologia , Salmonella enterica/isolamento & purificação , Sorogrupo , Suínos
5.
Transplant Proc ; 50(9): 2789-2793, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30401398

RESUMO

Japanese herbal medicines have long been used as alternative therapy because of their immunomodulatory effects. In recent years, use herbal medicines is rapidly increasing worldwide. In this study, we investigated the effect of 17 components of traditional Japanese herbal medicines on alloimmune responses in a murine model of cardiac allograft transplantation. Fully vascularized heterotopic hearts from C57BL/6 donors were transplanted into CBA mice by using microsurgical techniques. Artemisiae capillaris herba (Inchinko) was given to CBA recipients at a dosage of 1 g/kg/day from the day of transplantation until 7 days afterward. The other 16 components were given at a dosage of 2 g/kg/day for the same time period. Naïve CBA mice rejected C57BL/6 cardiac grafts acutely (median survival time [MST] of 7 days). CBA transplant recipients given 2 g/kg/day of Glycyrrhizae radix (Kanzou), Poria sclerotium (Bukuryo), Pinellia tuber (Hange), Cnidii rhizome (Senkyu), Paeoniae radix (Shakuyaku), and Scutellariae radix (Ogon) had prolonged C57BL/6 allograft survival significantly (MSTs were 18, 18, 17, 14, 12, and 12 days, respectively). Moreover, CBA transplant recipients given 1g/kg/day of Artemisiae capillaris herba had prolonged C57BL/6 allograft survival (MST >100 days); however, none of other 10 components prolonged allograft survival. In conclusion, administration of 7 components of traditional Japanese herbal medicines might induce prolongation of fully major histocompatibility complex-mismatched cardiac allografts.


Assuntos
Sobrevivência de Enxerto/efeitos dos fármacos , Transplante de Coração , Coração , Imunossupressores/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais , Aloenxertos/efeitos dos fármacos , Animais , Coração/efeitos dos fármacos , Complexo Principal de Histocompatibilidade/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Transplante Homólogo
6.
Transplant Proc ; 50(9): 2794-2797, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30401399

RESUMO

Thrombomodulin (TM) is a promising natural anti-coagulant therapeutic protein that is effective in the treatment of disseminated intravascular coagulation. However, the mechanisms by which TM on micro-vessels enable the regulation of intimal hyperplasia remain elusive. We investigated the graft-protective effects of TM in a fully major histocompatibility complex-mismatched murine cardiac allograft transplantation model. CBA recipients transplanted with a C57BL/6 heart received intraperitoneal administration of 0.2, 2.0, and 20.0 µg/day of TM for 8 days. Histological staining was conducted to assess the degree of inflammation and infiltration in the transplanted cardiac grafts. Untreated CBA recipients rejected C57BL/6 cardiac grafts acutely (median survival time [MST] was 7 days). CBA recipients exposed to the above dosages had significantly prolonged allograft survival (MSTs were 16, 21, and 37.5 days, respectively). Histologic assessments from TM-exposed recipients 2 weeks after grafting showed that the myocardium and vessel structure in their allografts were clearly preserved, and that the infiltration of inflammatory cells around coronary arteries was suppressed. TM can induce the prolongation of fully major histocompatibility complex-mismatched cardiac allograft by exerting graft protective effects within the myocardium and coronary arteries.


Assuntos
Aloenxertos/efeitos dos fármacos , Sobrevivência de Enxerto/efeitos dos fármacos , Transplante de Coração , Coração/efeitos dos fármacos , Trombomodulina/administração & dosagem , Animais , Vasos Coronários/efeitos dos fármacos , Injeções Intraperitoneais , Complexo Principal de Histocompatibilidade , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Miocárdio/patologia , Transplante Homólogo
7.
Transplant Proc ; 50(9): 2798-2803, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30401400

RESUMO

The hippocampus is a brain structure that plays a fundamental role in memory and learning. Many animal studies have demonstrated that the structure of the hippocampus has evolved through exercise and play. However, little is known on the relationship between the brain and immunological reaction. In this study, we investigated the correlation between the weight of the hippocampus and transplant immunology in a murine heart transplant model. Fully vascularized heterotopic hearts from CBA (H2k, allogeneic group) or C57BL/6 (H2b, syngeneic group) donors were transplanted into C57BL/6 recipients by using microsurgical techniques. The weights of the whole brain and hippocampus from syngeneic and allogeneic groups were recorded 1, 2, and 4 weeks after grafting, and histologic assessments were performed. The syngeneic group maintained beating cardiac grafts for over 30 days, but the allogeneic group rejected CBA cardiac allografts acutely within 8 days. The average weight of whole brain from syngeneic and allogeneic group 1, 2, and 4 weeks had no significant differences. However, the average weight of hippocampus at 2 and 4 weeks was considerably increased in the allogeneic group compared with the syngeneic group. Histologic assessments with hematoxylin-eosin and Kluver-Barrera staining of hippocampus from allogeneic group 1 week after grafting demonstrated a greater number of granule and pyramidal cells in the hippocampus. Alloimmune responses in our model increase the weight of hippocampus.


Assuntos
Sobrevivência de Enxerto/imunologia , Transplante de Coração/métodos , Hipocampo/patologia , Animais , Hipocampo/imunologia , Histocompatibilidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Tamanho do Órgão , Período Pós-Operatório , Transplante Homólogo , Transplante Isogênico
8.
Transplant Proc ; 50(9): 2804-2806, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30401401

RESUMO

The HMG-CoA reductase inhibitor (statin), which reduces serum cholesterol, has been demonstrated in the control of immune responses and may potentially play an important role in the regulation of acute and chronic rejection in organ transplantations. We investigated the graft-protective effect of a kind of statin, pravastatin, in the survival of fully major histocompatibility complex--mismatched murine cardiac allograft transplantation. Fully vascularized heterotopic hearts from C57BL/6 donors were transplanted into CBA recipients through microsurgical techniques. CBA recipients transplanted with a C57BL/6 heart received oral administration of 40, 120, or 400 µg/kg/day of pravastatin from the day of transplantation to 7 days afterward. Immunohistochemical staining studies were performed to determine whether intimal formation of coronary arteries in the transplanted cardiac allografts was preserved and also to conduct morphometric analysis. Untreated CBA recipients rejected C57BL/6 cardiac grafts acutely (median survival time [MST] 7 days). CBA recipients exposed with 40 and 120 µg/kg/day of pravastatin had a small prolonged allograft survival (MSTs of 10 and 9 days, respectively). However, the MST of CBA recipients exposed to 400 µg/kg/day of pravastatin was significantly effective for allograft survival (MST 50 days). Immunohistochemical staining assessments on 4 weeks after grafting showed suppression of intimal hyperplasia in allograft coronary arteries. Pravastatin could induce the prolongation of fully major histocompatibility complex--mismatched cardiac allograft through the protection of the coronary artery.


Assuntos
Aloenxertos/efeitos dos fármacos , Transplante de Coração/métodos , Coração/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Pravastatina/farmacologia , Animais , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/imunologia , Sobrevivência de Enxerto/efeitos dos fármacos , Sobrevivência de Enxerto/imunologia , Complexo Principal de Histocompatibilidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Transplante Homólogo
9.
Transplant Proc ; 50(1): 274-282, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29407322

RESUMO

Shigyakusan (also known as Tsumura Japan [TJ]-35) is composed of peony, bitter orange, licorice, and Bupleuri radix is used for cholecystitis and gastritis as an anti-inflammatory agent. We investigated the effect of TJ-35 on alloimmune response in a murine heart transplantation model. CBA mice that underwent transplantation of a C57BL/6 (B6) heart were assigned to four groups: no treatment, TJ-35-exposed, each component-exposed, or each component missing-exposed. The four groups above each received oral administration of TJ-35, each component, or TJ-35 with each component missing from the day of transplantation until 7 days, respectively. Untreated CBA recipients rejected B6 cardiac grafts acutely (median survival time [MST], 7 days). TJ-35-exposed CBA recipients had significantly prolonged B6 allograft survival (MST, 20.5 days). However, MSTs of CBA recipients that had been administered each component and TJ-35 with each component missing did not reach that of TJ-35-exposed recipients. Adoptive transfer of CD4+ splenocytes from TJ-35-exposed primary allograft recipients resulted in significant prolonged allograft survival in naïve secondary recipients (MST, 63 days). Flow cytometry studies showed that the percentage of CD4+CD25+Foxp3+ cell population was increased in TJ-35-exposed CBA recipients. In conclusion, TJ-35-induced prolongation of fully allogeneic cardiac allografts and may generate regulatory CD4+CD25+Foxp3+ cells in our model. The effect seemed to require all components of TJ-35.


Assuntos
Aloenxertos/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Transplante de Coração , Coração/efeitos dos fármacos , Complexo Principal de Histocompatibilidade/efeitos dos fármacos , Linfócitos T Reguladores/efeitos dos fármacos , Transferência Adotiva , Aloenxertos/imunologia , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Transplante de Coração/métodos , Japão , Complexo Principal de Histocompatibilidade/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Miocárdio/imunologia , Linfócitos T Reguladores/imunologia
10.
Transplant Proc ; 50(1): 283-292, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29407323

RESUMO

Rikkunshito (TJ-43), an eight-component traditional Japanese herbal medicine, has been used in clinics for gastritis, vomiting, and appetite loss. We investigated the effects of TJ-43 on the amelioration of appetite loss in the surgical-exposed model of murine cardiac allograft transplantation. CBA mice underwent transplantation of a CBA (syngeneic group) or C57BL/6 heart (allogeneic group) and received oral administration of 2 g/kg/d of TJ-43 from the day of transplantation until 7 days afterward. The amount of food intake (FI) and weight change after operation were recorded from 1 to 28 postoperative days. The allogeneic group had less average amounts of FI for 1 week compared with the syngeneic group (FI was 1.90 ± 0.43 g and 2.66 ± 0.46 g, respectively). Average FIs between the syngeneic and allogeneic groups with TJ-43 for 1 week were 2.36 ± 0.44 g and 2.30 ± 0.13 g, respectively, and those with distilled water were 2.66 ± 0.46 g and 1.90 ± 0.43 g, respectively, suggesting that exposure with TJ-43 tended to ameliorate the reduction of FI. Similarly, the effect on the amelioration of average FI in syngeneic and allogeneic groups exposed for 2 weeks was confirmed. However, exposure to with TJ-43 had no effects on FI after 4 weeks. TJ-43 could prevent reduction of average FI induced by the surgical-exposed model of murine cardiac allograft transplantation.


Assuntos
Regulação do Apetite/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Transplante de Coração/efeitos adversos , Fitoterapia/métodos , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Período Pós-Operatório
11.
Clin Exp Dermatol ; 43(3): 286-290, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29266423

RESUMO

Centrifugal lipodystrophy (CLD), characterized by a depressed lesion in the abdominal skin, is a chronic disease occurring more often among younger patients of East Asian descent. We present an extremely unusual case of CLD of the scalp associated with reversible hair loss. The patient demonstrated alopecia in the frontal, temporal and occipital areas of the scalp, which connected to form a ring-shaped area of hair loss. Curiously, the area of hair loss gradually expanded outwards while the central region showed normal hair regrowth. Immunohistochemical analysis demonstrated reduced expression of leptin, an adipokine capable of inducing the anagen phase of the hair cycle, in the adipose tissue, associated with active inflammation. By contrast, recovery of leptin expression was observed at sites of healed inflammatory lesions, suggesting that reversible hair loss might be caused by a change in leptin expression in adipose tissue.


Assuntos
Alopecia/patologia , Lipodistrofia/patologia , Dermatoses do Couro Cabeludo/patologia , Couro Cabeludo/patologia , Alopecia/diagnóstico por imagem , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Feminino , Humanos , Lipodistrofia/diagnóstico por imagem , Imageamento por Ressonância Magnética , Couro Cabeludo/imunologia , Dermatoses do Couro Cabeludo/diagnóstico por imagem , Pele/imunologia , Pele/patologia , Adulto Jovem
12.
Chem Commun (Camb) ; 53(70): 9781-9784, 2017 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-28816304

RESUMO

Molecular oxygen serves as a useful oxidant for the glycol scission of 1,2-diols and the Hofmann rearrangement of primary amides using pentamethyliodobenzene as a catalyst. The use of isobutyraldehyde and Lewis basic nitriles under O2 enabled the iodine(i)/(iii) catalytic cycle, where in situ-generated peracid acts as a terminal oxidant.

13.
Transplant Proc ; 49(6): 1477-1482, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28736026

RESUMO

Yogurt is a nutrient-rich food and the beneficial effects of yogurt on both health and immunomodulatory effects are well documented. In this pilot study, we investigated the effects of commercially produced yogurt R-1 on alloimmune responses in a murine cardiac transplantation model. The R-1 is produced by Meiji Co., Ltd., and contains live and active lactic acid bacteria (lactobacillus bulgaricus OLL1073R-1) mainly. CBA (H2k) mice underwent transplantation of a C57BL/6 (H2b; B6) heart and received oral administration of 1 mL, 0.1 mL, and 0.01 mL of R-1 from the day of transplantation until 7 days afterward. Additionally, we prepared one group of CBA recipients given 1 mL of R-1 sterilized by microwave for 7 days. Histological and immunohistochemical studies were performed. Naïve CBA mice rejected B6 cardiac graft acutely (median survival time [MST]: 7 days). CBA recipients given of 1 mL of R-1 had significantly prolonged B6 allograft survival (MST, 27 days). However, other doses of 0.1 mL and 0.01 mL of R-1 did not prolonged allograft survival (MSTs, 9 days and 8.5 days, respectively). Also, CBA recipients administered microwaved R-1 had no prolongation of B6 allograft (MST, 9 days). Histological and immunohistochemical studies showed the cardiac allograft from R-1-exposed CBA recipients had preserved graft and vessel structure and the number of infiltrated CD4+, CD8+, and Foxp3+ cells in R-1-exposed CBA recipients increased, respectively. In conclusion, our findings imply that yogurt containing active lactic acid bacteria could change alloimmune responses partially and induce the prolongation of cardiac allograft survival via CD4+Foxp3+ regulatory cells.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Fatores de Transcrição Forkhead/imunologia , Sobrevivência de Enxerto/fisiologia , Transplante de Coração , Iogurte , Fenômenos Fisiológicos da Nutrição Animal/imunologia , Animais , Complexo Principal de Histocompatibilidade/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Projetos Piloto
14.
Transplant Proc ; 47(8): 2528-32, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26518964

RESUMO

Overeating and obesity lead to cardiovascular disease, diabetes, and eventually premature death, whereas food or energy restriction reduces risk factors for cardiovascular disease and diabetes and expands the life span. The aim of this study was to investigate the effect of food restriction (FR) in a murine heart transplant model. CBA male recipients (H2(k)) that underwent transplantation of C57BL/6 (H2(b)) hearts were assigned to free access group or FR groups with food intake at 60% (40% FR), 50% (50% FR), or 40% (60% FR) of the average food intake for 1 week after transplantation, and each median survival time was measured. We also performed cell proliferation, cytokine production, and flow cytometry assessments. The 60% FR CBA recipients showed prolongation of allograft survival (median survival time, 24 days). Cell proliferation and interferon-γ were suppressed in the 60% FR CBA recipients. Flow cytometry studies showed a lower CD4(+)CD25(+)Foxp3(+) cell population in splenocytes from the 60% FR CBA recipients. In conclusion, the findings suggest that the prolongation of cardiac allograft resulted from not regulation of alloimmune responses, but partial impairment of alloimmune responses, linking energy restriction to low generation of splenic CD4(+)CD25(+)Foxp3(+) regulatory T cells.


Assuntos
Aloenxertos/fisiologia , Regulação do Apetite , Sobrevivência de Enxerto/fisiologia , Transplante de Coração , Animais , Regulação do Apetite/imunologia , Proliferação de Células , Citocinas/metabolismo , Metabolismo Energético/imunologia , Citometria de Fluxo , Sobrevivência de Enxerto/imunologia , Transplante de Coração/métodos , Histocompatibilidade , Interferon gama/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Baço/imunologia , Linfócitos T Reguladores/metabolismo , Transplante Homólogo
15.
Chem Commun (Camb) ; 51(27): 5836-9, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25686576

RESUMO

A simple and versatile solution-processing method based on molecular self-assembly is used to fabricate organic single crystal microwires of a low bandgap quinoidal oligothiophene derivative. Individual single crystal microwire transistors present well-balanced ambipolar behaviour with hole and electron mobilities as high as 0.4 and 0.5 cm(2) V(-1) s(-1), respectively.


Assuntos
Elétrons , Tiofenos/química , Transistores Eletrônicos , Cristalização , Nanofios/química , Nanofios/ultraestrutura , Soluções
16.
Phys Chem Chem Phys ; 16(32): 16941-56, 2014 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-25005146

RESUMO

We investigate the photophysical and amplified spontaneous emission properties of a series of monodisperse solution-processable oligofluorenes functionalized with hexyl chains at the C9 position of each fluorene unit. Thin films of these oligofluorenes are then used in organic field-effect transistors and their charge transport properties are examined. We have particularly focused our attention on the influence of oligofluorene length on the absorption and steady-state fluorescence spectra, on the HOMO/LUMO energy levels, on the photoluminescence lifetime and quantum yield as well as on the amplified spontaneous emission properties and the charge carrier mobilities. Differential scanning calorimetry and X-ray diffraction measurements demonstrate that, among all oligofluorene derivatives used in this study, only the structure and morphology of the pentafluorene film is significantly modified by a thermal treatment above the glass transition temperature, resulting in a 9 nm blue-shift of the fluorescence spectrum without significant changes in the photoluminescence quantum yield and in the amplified spontaneous emission threshold. In parallel, hole field-effect mobility is significantly increased from 8.6 × 10(-7) to 3.8 × 10(-5) cm(2) V(-1) s(-1) upon thermal treatment, due to an increase of crystallinity. This study provides useful insights into the morphological control of oligofluorene thin films and how it affects their photophysical and charge transport properties. Moreover, we provide evidence that, because of the low threshold, the tunability of the amplified spontaneous emission and the photostability of the films, these oligofluorenes are promising candidates for organic solid-state laser applications.

17.
Transplant Proc ; 46(4): 1175-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24815154

RESUMO

Herbal medicines have been used for over 3,000 years in Asian as alternative therapy for their variety effects and have recently become popular in Europe and the United States. In the last 30 years, Japanese herbal medicines were widely used for treatment of diseases after been recognized officially by Japanese government. In this study, we investigated the effect of 34 kinds of traditional Japanese herbal medicines on alloimmune responses in a murine model of cardiac allograft transplantation. CBA mice (H2(k)) underwent transplantation of a C57BL/6 (H2(b)) heart and received oral administration of 2 g/kg/d of the 34 kinds of herbal medicines from the day of transplantation until 7 days afterward. Naïve CBA mice rejected B6 cardiac grafts acutely (median survival time [MST], 7 days). CBA transplant recipients given 2 g/kg/d of Sairei-to (TJ-114) and Tokishakuyaku-san (TJ-23) had prolonged C57BL/6 allograft survival indefinitely (both MSTs > 100 days). Moreover, CBA transplant recipients given Seisinrensiin (TJ-111), Tokishigyakukagoshuyushokyoto (TJ-38), Rikkunshito (TJ-43), Maobushisaishinto (TJ-127), Ninjin-yoei-to (TJ-108), Ryokan-kyomi-shinge-nin-to (TJ-119), Inchingorei-san (TJ-117), Hochuekkito (TJ-41), Kihi-to (TJ-65), and Sinbu-to (TJ-30) had also prolonged C57BL/6 allograft survival significantly (MSTs of 28, 22, 16, 14, 14, 13, 12, 9.5, 9 and 9 days, respectively). However, none of other 22 kinds of herbal medicines could prolong the allograft survival. Furthermore, oral administration of 2 g/kg/d of Daikenchuto (TJ-100) induced sudden death (within 1 minute) in CBA mice. In conclusion, 12 kinds of Japanese herbal medicines prolonged allograft survival and one showed toxic effect in mice.


Assuntos
Sobrevivência de Enxerto/efeitos dos fármacos , Transplante de Coração , Medicina Tradicional do Leste Asiático , Preparações de Plantas/farmacologia , Administração Oral , Aloenxertos , Animais , Esquema de Medicação , Transplante de Coração/efeitos adversos , Japão , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Modelos Animais , Fitoterapia , Preparações de Plantas/administração & dosagem , Preparações de Plantas/toxicidade , Plantas Medicinais , Fatores de Tempo
18.
Phys Chem Chem Phys ; 15(44): 19213-20, 2013 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-24108348

RESUMO

Electronic excited states of a strongly correlated organic radical, 1,3,5-trithia-2,4,6-triazapentalenyl (TTTA), adsorbed on a Si(001) surface were investigated by means of two-photon photoemission spectroscopy (2PPE) to elucidate the functional organic thin-film formation on a typical semiconductor substrate. The spectra were interpreted with the aid of density functional theoretical calculations. The unpaired electron of TTTA forms a covalent bond with the dangling bond of the Si-dimer initially, and there are resonant states of TTTA to Si near the surface. The molecules adsorbed at room temperature form dimers having diamagnetic properties at thicknesses of a few monolayers, while the paramagnetic phase appears at multilayer thickness. From the change in the work function, the orientation of the adsorbed TTTA molecules was determined to change depending on the thickness of the adsorbed layer.

19.
Phys Chem Chem Phys ; 15(8): 2867-72, 2013 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-23337941

RESUMO

We report on singlet-singlet annihilation and exciton diffusion in as-prepared p-type and annealed n-type thin films of the low-bandgap quinoidal quaterthiophene [QQT(CN)4] using ultrafast transient absorption measurements. The decay dynamics of exciton populations are well described by a one-dimensional diffusion-limited bimolecular recombination, indicating that the singlet excitons migrate preferentially along the stacking direction. Our results show that the exciton diffusion constants in QQT(CN)4 films do not vary significantly upon thermal annealing. Exciton diffusion lengths are measured to be as high as 4 and 5 nm in as-prepared and annealed QQT(CN)4 films, respectively. We also observe an influence of the excitation densities on the singlet exciton diffusion, which is attributed to phonon scattering. Because of the possibility of patterning p-n regions in QQT(CN)4 films by thermal nanolithography techniques, this study provides important insight not only into the photophysical properties of quinoidal oligothiophene derivatives but also for their future integration into high-performance p-n nanostructured near infrared light-sensing devices.

20.
J Neuroendocrinol ; 25(3): 312-21, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23163696

RESUMO

The present study aimed to investigate the distribution of the octadecaneuropeptide (ODN) in the goldfish brain and to look for a possible effect of ODN on somatolactin (SL) release from pituitary cells. A discrete population of ODN-immunoreactive neurones was localised in the lateral part of the nucleus lateralis tuberis. These neurones sent projections through the neurohypophyseal tract towards the neurohypophysis, and nerve fibres were seen in the close vicinity of SL-producing cells in the pars intermedia. Incubation of cultured goldfish pituitary cells with graded concentrations of ODN (10(-9) -10(-5 ) m) induced a dose-dependent stimulation of SL-ß, but not SL-α, release. ODN-evoked SL release was blocked by the metabotrophic endozepine receptor antagonist cyclo(1-8) [DLeu(5) ]OP but was not affected by the central-type benzodiazepine receptor antagonist flumazenil. ODN-induced SL release was suppressed by treatment with the phospholipase C (PLC) inhibitor U-73122 but not with the protein kinase A (PKA) inhibitor H-89. These results indicate that, in fish, ODN produced by hypothalamic neurones acts as a hypophysiotrophic neuropeptide stimulating SL release. The effect of ODN is mediated through a metabotrophic endozepine receptor positively coupled to the PLC/inositol 1,4,5-trisphosphate/protein kinase C-signalling pathway.


Assuntos
Proteínas de Peixes/metabolismo , Glicoproteínas/metabolismo , Neuropeptídeos/farmacologia , Hipófise/efeitos dos fármacos , Hormônios Hipofisários/metabolismo , Animais , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Carpa Dourada , Imuno-Histoquímica , Hipófise/citologia , Hipófise/metabolismo , Fosfolipases Tipo C/antagonistas & inibidores
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