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2.
Transplant Proc ; 50(10): 3249-3254, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30577193

RESUMEN

Preceding solo kidney transplantation for type 1 diabetes with end-stage renal failure is controversial because of less pancreatic graft survival in pancreas transplantation after kidney transplantation (PAK) than in simultaneous pancreas and kidney transplantation (SPK). METHODS: To study the effectiveness of preceding solo kidney transplantation for type 1 diabetes with end-stage renal failure, comparative retrospective analysis was performed between SPK (n = 232) and PAK (n = 39) that were performed until December 2016. RESULTS: At 1, 3, and 5 years, pancreatic graft survival in SPK was 87.5%, 86.4%, and 82.8%, respectively, and 87.1%, 65.0%, and 49.1%, respectively, in PAK, which showed lesser long-term graft survival than SPK. Because 10 cases out of 16 (62.5%) failed into pancreatic graft loss with rejection in PAK, which was about 3 times more than in SPK, control of rejection is very important; rejection episodes were decreased by rabbit antithymocyte globulin induction resulting in improved graft survival. Five-year patient survival was 88.0% in SPK and 96.6% in PAK. CONCLUSION: Considering patient survival, preceding solo kidney transplantation for type 1 diabetes with end-stage renal failure should be performed if a donor is available.


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Trasplante de Riñón/métodos , Trasplante de Páncreas/métodos , Adulto , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/mortalidad , Femenino , Supervivencia de Injerto , Humanos , Fallo Renal Crónico/etiología , Fallo Renal Crónico/mortalidad , Fallo Renal Crónico/cirugía , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
3.
Transplant Proc ; 50(5): 1482-1488, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29880375

RESUMEN

BACKGROUND: Several studies have suggested that decreased muscle volume is associated with attenuation of immune function. The recipient's immune system is responsible for rejection of transplanted organs, which is a major cause of graft loss after transplantation. We aimed to determine whether muscle volume is correlated with graft survival after pancreas transplantation (PT). METHODS: Forty-three patients underwent PT for type 1 diabetes mellitus at our institution from August 2001 to May 2016. The quantity of skeletal muscle was evaluated using the psoas muscle mass index (PMI). The correlation between PMI and outcome after PT was assessed. RESULTS: A total of 32 and 11 recipients underwent simultaneous pancreas-kidney transplantation (SPK) and PT alone/pancreas after kidney transplantation, respectively. Patients with a surviving graft showed a significantly lower PMI than those with graft loss (P = .0451). We divided the recipients into two groups according to the PMI cutoff values, which were established using receiver operating characteristic curves. The cumulative graft survival rate was significantly higher in patients with a low PMI (P = .0206). A multivariate Cox regression analysis revealed that a low PMI (P = .0075) is an independent predictive factor for better graft survival. A low PMI was not a significant predictive factor for acute rejection, but was an independent predictive factor for graft survival after the first acute rejection (P = .0025). CONCLUSIONS: Our data suggest that muscle volume could be a predictor of graft survival after PT.


Asunto(s)
Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/cirugía , Supervivencia de Injerto/fisiología , Trasplante de Páncreas , Sarcopenia/complicaciones , Adulto , Área Bajo la Curva , Estudios de Cohortes , Femenino , Rechazo de Injerto , Humanos , Trasplante de Riñón , Masculino , Persona de Mediana Edad , Análisis Multivariante , Músculos Psoas/patología , Curva ROC , Estudios Retrospectivos , Sensibilidad y Especificidad
4.
Transplant Proc ; 49(5): 1133-1137, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28583543

RESUMEN

BACKGROUND: Living pancreas transplantation plays an important role in the treatment of patients with severe type 1 diabetes. However, pancreatectomy is very invasive for the donor, and less-invasive surgical procedures are needed. Although some reports have described hand-assisted laparoscopic surgery for distal pancreatectomy in living-donor operations, less-invasive laparoscopy-assisted (LA) procedures are expected to increase the donor pool. We herein report the outcomes of four cases of LA spleen-preserving distal pancreatectomy (Warshaw technique [WT]) in living pancreas donors. PATIENTS AND METHODS: Four living pancreas donors underwent LA-WT at our institution from September 2010 to January 2013. All donors fulfilled the donor criteria established by the Japan Society for Pancreas and Islet Transplantation. RESULTS: The median donor age was 54 years. Two donors underwent left nephrectomy in addition to LA-WT for simultaneous pancreas-kidney transplantation. The median donor operation time for pancreatectomy was 340.5 minutes. The median pancreas warm ischemic time was 3 minutes. The median donor blood loss was 246 g. All recipients immediately achieved insulin independence. One donor required reoperation because of obstructive ileus resulting from a port-site hernia. Another donor developed a pancreatic fistula (International Study Group of Pancreatic Fistula grade B), which was controlled with conservative management. After a maximum follow-up of 73 months, no clinically relevant adverse events had occurred. These results were comparable with those of previous studies concerning living-donor pancreas transplantation. CONCLUSION: The LA-WT is a safe and acceptable operation for living-donor pancreas transplantation.


Asunto(s)
Laparoscopía/métodos , Donadores Vivos , Trasplante de Páncreas/métodos , Pancreatectomía/métodos , Recolección de Tejidos y Órganos/métodos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Páncreas/cirugía
5.
Transplant Proc ; 47(3): 733-7, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25891721

RESUMEN

BACKGROUND: Simultaneous pancreas-kidney transplantation (SPK) is a definitive treatment for type 1 diabetics with end-stage renal disease (ESRD). Because of the shortage of deceased donors in Japan, the mortality rate during the waiting period is high. We evaluated mortality risk in patients with type 1 diabetes waiting for SPK, and the benefit of living-donor kidney transplantation (LDK) preceding pancreas transplantation, which may reduce mortality in patients awaiting SPK. METHODS: This retrospective study included 71 patients with type 1 diabetes. Twenty-six patients underwent SPK, 15 underwent LDK, and 30 were waiting for SPK. Their cumulative patient and graft survival rates were retrospectively evaluated. Risk factors contributing to mortality in patients with type 1 diabetes awaiting SPK were evaluated with the use of a Cox proportional hazards model. RESULTS: The 5-year cumulative patient survival rates in the SPK and LDK groups were 100% and 93.3%, respectively (P = .19), and 5-year kidney graft survival rates were 95.7% and 100% (P = .46), respectively. The cumulative survival rate in patients awaiting SPK was 77.7% at 5 years after registration. Duration of dialysis was the only factor significantly associated with patient and graft survivals according to both univariate and multivariate analyses. CONCLUSIONS: Patient and graft survival rates were similar in the SPK and LDK groups, but the survival rate of patients awaiting SPK decreased over time. Duration of dialysis was an independent risk factor for patient and graft survival. LDK preceding pancreas transplantation may be an effective therapeutic option for patients with type 1 diabetes and ESRD.


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Fallo Renal Crónico/cirugía , Trasplante de Riñón/métodos , Donadores Vivos , Trasplante de Páncreas/métodos , Adulto , Anciano , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/mortalidad , Femenino , Supervivencia de Injerto , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/mortalidad , Trasplante de Riñón/mortalidad , Masculino , Persona de Mediana Edad , Análisis Multivariante , Trasplante de Páncreas/mortalidad , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Resultado del Tratamiento
6.
Transplant Proc ; 47(3): 608-11, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25817610

RESUMEN

BACKGROUND: Renal transplantation has been established as a treatment for end-stage renal disease (ESRD) due to diabetic nephropathy. However, few studies have focused on the outcome after renal transplantation in patients with ESRD and type 2 diabetic nephropathy. To investigate the effect of renal transplantation on ESRD with type 2 diabetic nephropathy, we retrospectively analyzed patients who received renal transplantation at our facility. This study aimed to compare the outcome of renal transplantation for type 2 diabetic nephropathy with that for nondiabetic nephropathy. METHODS: We studied 290 adult patients, including 65 with type 2 diabetic nephropathy (DM group) and 225 with nondiabetic nephropathy (NDM group), who underwent living-donor renal transplantation at our facility from February 2008 to March 2013. We compared the 2 groups retrospectively. RESULTS: In the DM and NDM groups, the 5-year patient survival rates were 96.6% and 98.7%, and the 5-year graft survival rates were 96.8% and 98.0%, respectively, with no significant differences between the groups. There were no significant differences in the rates of surgical complications, rejection, and infection. The cumulative incidence of postoperative cardiovascular events was higher in the DM group than in the NDM group (8.5% vs 0.49% at 5 years; P = .002). CONCLUSIONS: Patient and graft survival rates after renal transplantation for type 2 diabetic nephropathy are not inferior to those for recipients without diabetic nephropathy. Considering the poor prognosis of patients with diabetic nephropathy on dialysis, renal transplantation can provide significant benefits for these patients.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas/cirugía , Fallo Renal Crónico/cirugía , Trasplante de Riñón/mortalidad , Adulto , Anciano , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Femenino , Supervivencia de Injerto , Humanos , Incidencia , Trasplante de Riñón/efectos adversos , Donadores Vivos , Masculino , Persona de Mediana Edad , Diálisis Renal/efectos adversos , Estudios Retrospectivos , Tasa de Supervivencia
7.
Transplant Proc ; 45(8): 2903-6, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24157001

RESUMEN

BACKGROUND: Various studies have reported poorer graft survival among individuals displaying T-cell-positive flow cytometry crossmatches (FCXM). Good outcomes have been observed in immunologically high-risk patients with the use of rituximab, plasmapheresis, and γ-globulin. Because the relevance of FCXM B-cell-positivity (BCXM (+)) alone remains controversial, we examined its impact on living donor renal transplantations. PATIENTS AND METHODS: We retrospectively studied 146 adult renal transplantation recipients from April 2007 to June 2012, dividing the patients into BCXM (+) (n = 31) versus BCXM (-) recipients (n = 115). We examined patient and graft survivals as well as rejection rates at 0 to 3, 3 to 12, and 12 to 24 months. We also determined the incidence of infectious diseases. We performed stepwise multivariate regression to identify risk factors contributing rejection episodes. RESULTS: One-year patient and graft survivals were 100% in both groups. The BCXM (-) group have a 16.8% rejection probability whereas the BCXM (+) group, 33.2% (P = .201). There were no significantly differences in the incidence of infectious diseases. Only the rate of a sensitizing history was an independent risk factor for a rejection episode. CONCLUSION: BCXM (+) showed only a tendency but not a significant impact on rejection episodes compared with BCXM (-); short-term graft survivals were similar.


Asunto(s)
Linfocitos B/inmunología , Citometría de Flujo/métodos , Prueba de Histocompatibilidad , Trasplante de Riñón , Donadores Vivos , Adulto , Femenino , Rechazo de Injerto , Supervivencia de Injerto , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
8.
Transplant Proc ; 45(6): 2469-75, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23953564

RESUMEN

The outcomes of organ transplantation have improved due to better immunosuppressive drugs, surgical techniques, and management of complications. However, ischemia-reperfusion injury remains a challenge affecting graft survival. In this study, we employed injection of a protein transduction domain (PTD) to inhibit the c-Jun NH2-terminal kinase (JNK) pathway thereby attenuating ischemia-reperfusion injury in a porcine model. The PTD-JNK inhibitor (JNKI) was administered into the renal artery, allowing it to be taken into various elements including vascular endothelial cells by endocytosis via the PTD. Serum creatinine and blood urea nitrogen concentrations were lower among PTD-JNKI than controls. In addition, renal tissue blood flow was maintained in the PTD-JNKI group, resulting in less tissue injury and fewer apoptotic cells. These results suggested that the PTD technique improved renal transplantation outcomes.


Asunto(s)
Péptidos de Penetración Celular/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos/antagonistas & inhibidores , Enfermedades Renales/prevención & control , Riñón/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Daño por Reperfusión/prevención & control , Animales , Apoptosis/efectos de los fármacos , Biomarcadores/sangre , Nitrógeno de la Urea Sanguínea , Permeabilidad de la Membrana Celular , Péptidos de Penetración Celular/administración & dosificación , Péptidos de Penetración Celular/metabolismo , Isquemia Fría/efectos adversos , Creatinina/sangre , Citoprotección , Modelos Animales de Enfermedad , Endocitosis , Femenino , Inyecciones Intraarteriales , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Riñón/irrigación sanguínea , Riñón/enzimología , Riñón/patología , Enfermedades Renales/enzimología , Enfermedades Renales/etiología , Enfermedades Renales/patología , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/metabolismo , Arteria Renal , Circulación Renal/efectos de los fármacos , Daño por Reperfusión/enzimología , Daño por Reperfusión/etiología , Daño por Reperfusión/patología , Porcinos , Factores de Tiempo , Factor de Necrosis Tumoral alfa/sangre , Resistencia Vascular/efectos de los fármacos
9.
Health Phys ; 104(3): 243-50, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23361418

RESUMEN

Because of radioactive fallout resulting from the Fukushima Daiichi Nuclear Power Plant (NPP) accident, water discharge from many outdoor swimming pools in Fukushima was suspended out of concern that radiocesium in the pool water would flow into farmlands. The Japan Atomic Energy Agency has reviewed the existing flocculation method for decontaminating pool water and established a practical decontamination method by demonstrating the process at eight pools in Fukushima. In this method, zeolite powder and a flocculant are used for capturing radiocesium present in pool water. The supernatant is discharged if the radiocesium concentration is less than the targeted level. The radioactive residue is collected and stored in a temporary storage space. Radioactivity concentration in water is measured with a NaI(Tl) or Ge detector installed near the pool. The demonstration results showed that the pool water in which the radiocesium concentration was more than a few hundred Bq L was readily purified by the method, and the radiocesium concentration was reduced to less than 100 Bq L. The ambient dose rates around the temporary storage space were slightly elevated; however, the total increase was up to 30% of the background dose rates when the residue was shielded with sandbags.


Asunto(s)
Descontaminación/métodos , Accidente Nuclear de Fukushima , Instituciones Académicas , Piscinas/normas , Hidróxido de Aluminio/química , Radioisótopos de Cesio/química , Radioisótopos de Cesio/aislamiento & purificación , Descontaminación/economía , Floculación , Protección Radiológica , Factores de Tiempo , Agua/química , Zeolitas/química
10.
Asian J Endosc Surg ; 5(2): 63-8, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22776366

RESUMEN

INTRODUCTION: Laparoscopic splenectomy using pneumoperitoneum has been performed since 1992. The gasless abdominal wall-lifting method for laparoscopic splenectomy was introduced as an alternative. This retrospective study was undertaken to compare results using the two techniques. METHODS: Between 1995 and 2010, 54 patients underwent laparoscopic splenectomy at a single institution; 30 underwent the procedure using the gasless technique and 24 using pneumoperitoneum. There were no significant differences between the two groups regarding age, sex or BMI, but more patients underwent concurrent operations in the pneumoperitoneum group. The abdominal wall-lift system with subcutaneous K-wires was used for the gasless method. RESULTS: Intraoperative blood loss was similar in the two groups (193.0 ± 196.7 mL gasless, 217.3 ± 296.6 mL pneumoperitoneum; P > 0.05), but operative time (182.1 ± 92.1 min, 135.1 ± 46.1 min; P < 0.05), and resected spleen weight (306.1 ± 297.7 g, 138 ± 81.0 g; P < 0.05) were significantly different. In the gasless group, additional procedures included conversion (n = 1), mini-laparotomy (n = 2), and CO(2) insufflation (n = 2). Excluding the concurrent living-related kidney donor patients, hospital stay was similar (6.9 ± 2.5 days, 6.3 ± 2.0 days, P > 0.05). CONCLUSION: Although gasless laparoscopic splenectomy is feasible, there are disadvantages, particularly the restricted operative working space in some patients. These results suggest that either technique may be used on an individual basis in patients undergoing laparoscopic splenectomy.


Asunto(s)
Pared Abdominal/cirugía , Laparoscopía/métodos , Neumoperitoneo Artificial , Esplenectomía/métodos , Adolescente , Adulto , Anciano , Anemia Hemolítica/cirugía , Niño , Quistes/cirugía , Femenino , Humanos , Laparoscopía/instrumentación , Linfoma/cirugía , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Esplenectomía/instrumentación , Enfermedades del Bazo/cirugía , Trombocitopenia/cirugía , Resultado del Tratamiento , Adulto Joven
11.
Transplant Proc ; 43(5): 1489-94, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21693223

RESUMEN

BACKGROUND: Milrinone (MIL), a phosphodiesterase (PDE) 3 inhibitor, exhibits cardiotonic and angioectatic effects. Various PDE inhibitors have been shown to suppress inflammatory cytokines. In this study, we evaluated the angioectatic and anti-inflammatory cytokine effects of MIL on renal function after warm ischemia in a rat ischemia-reperfusion (I-R) injury model. MATERIALS AND METHODS: MIL or control solution was perfused from the left renal artery to the right kidney, and the left kidney was excised. The right renal artery, vein, and ureter were clamped and then released after 50 minutes to produce warm ischemia. We evaluated control (n = 7), MIL (n = 7), and sham operation (n = 7) groups for serum creatinine, blood urea nitrogen (BUN), blood flow, expression of tumor necrosis factor (TNF)-α mRNA, apoptosis index, and histological evidence of acute tubular necrosis. RESULTS: Serum creatinine and BUN concentrations peaked at 24 hours after reperfusion. MIL treatment significantly reduced serum creatinine (control group 1.27 ± 0.45 mg/dL vs MIL group 0.77 ± 0.19 mg/dL, P < .05; sham 0.35 ± 0.2 mg/dL) and BUN (control 67.6 ± 13.6 mg/dL vs MIL 51.0 ± 8.8 mg/dL, P < .05; sham 23.0 ± 4.2 mg/dL) levels at 24 hours. Thereafter, serum creatinine and BUN concentrations in the MIL group remained significantly lower compared with the control group for 120 hours (P < .05). MIL group exhibited significantly higher tissue blood flow, less acute tubular necrosis, lower expression of TNF-α mRNA in renal tissue, and lower apoptotic index (P < .05). CONCLUSIONS: MIL maintained renal tissue blood flow by its vasodilatory effect, suppressed expression of TNF-α mRNA by increasing intracellular cyclic adenosine monophosphate, and ultimately decreased tubular cell apoptosis, thus protecting renal function after warm I-R injury.


Asunto(s)
Riñón/efectos de los fármacos , Milrinona/uso terapéutico , Daño por Reperfusión/prevención & control , Animales , Secuencia de Bases , Nitrógeno de la Urea Sanguínea , Creatinina/sangre , Cartilla de ADN , Riñón/irrigación sanguínea , Ratas
12.
Transplant Proc ; 42(7): 2427-9, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20832520

RESUMEN

OBJECTIVE: Kidney grafts with multiple renal arteries (MRAs) are not uncommon, but they do make transplantation more difficult. Laparoscopic graft nephrectomy has become the standard; however, the safety and reliability must be maintained for both a donor and a recipient even in case of MRAs. This study evaluated the short-term outcomes of living donor renal transplant using grafts with MRAs procured by laparoscopic nephrectomy. PATIENTS AND METHODS: This study reviewed all living donor kidney transplantations performed from January 2008 to June 2009, which were divided into 3 groups according to the number of renal graft arteries. The serum creatinine level, warm ischemic time (WIT), rewarming time, total ischemic time (TIT), operative time, acute rejection episodes, and complications in each group were evaluated. RESULTS: The serum creatinine level showed no difference among the groups. Longer TIT was observed in the MRAs group, but WIT and rewarming time did not differ. The acute rejection rate was not different. There were no vessel complications in any donors and recipients. CONCLUSION: Harvesting kidney grafts with MRAs by laparoscopic nephrectomy requires a longer TIT; however, transplantation can be performed safely and reliably for both donors and recipients.


Asunto(s)
Trasplante de Riñón/métodos , Laparoscopía/métodos , Donadores Vivos , Nefrectomía/métodos , Arteria Renal/cirugía , Adolescente , Adulto , Anciano , Anastomosis Quirúrgica/métodos , Niño , Preescolar , Creatinina/sangre , Rechazo de Injerto/epidemiología , Humanos , Arteria Ilíaca/cirugía , Inmunosupresores/uso terapéutico , Trasplante de Riñón/inmunología , Laparoscopía/normas , Persona de Mediana Edad , Nefrectomía/normas , Estudios Retrospectivos , Seguridad , Recolección de Tejidos y Órganos/métodos
13.
Transplant Proc ; 41(10): 4274-6, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20005383

RESUMEN

OBJECTIVE: The aim of this study was to evaluate the availability of a pancreatic allograft biopsy via a laparotpmy. PATIENTS AND METHODS: From September 2004 to November 2007, 17 pancreas transplantations were performed: 15 simultaneous pancreas and kidney transplantations (SPK), 1 pancreas transplant alone (PTA), and one pancreas after kidney transplantation (PAK). Thirteen pancreatic allograft biopsies were obtained via an open laparotomy. This study evaluated the complications associated with this procedure, the rate of obtaining an adequate sample, and the relationship between biopsy-proven rejections and laboratory markers. In SPK cases we evaluated the synchronization between pancreas and kidney rejection. The pancreatic samples were diagnosed according to the Drachenberg classification. RESULTS: No complications resulted from the procedure. The rate of obtaining adequate samples was 84.6%. Pancreas rejection correlated with elevation of the laboratory markers in 71.4%. Simultaneous pancreas and kidney rejection occurred in 62.5%, only kidney in 25%, and only pancreas in 12.5%. CONCLUSION: A pancreas graft biopsy was absolutely imperative to improve the outcome in PTA, and even in SPK cases. A pancreatic allograft biopsy via a laparotomy was a safe, necessary and easy procedure to obtain an accurate diagnosis of rejection among pancreas transplantation patients.


Asunto(s)
Biopsia/métodos , Trasplante de Páncreas/patología , Rechazo de Injerto/patología , Humanos , Trasplante de Riñón/inmunología , Trasplante de Riñón/patología , Laparotomía/métodos , Cavidad Peritoneal/diagnóstico por imagen , Cavidad Peritoneal/patología , Estudios Retrospectivos , Trasplante Homólogo/patología , Ultrasonografía
14.
Artículo en Inglés | MEDLINE | ID: mdl-18519205

RESUMEN

Epitaxial 0.67Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3)-0.33PbTiO(3) (PMN-PT) thin films with electro-optic effects were fabricated on (PMN-PT) thin films with electro-optic effects were fabricated on (La0(0.5)Sr0(0.5))CoO(3) (LSCO)/CeO(2)/YSZ-buffered Si(001) substrates using double-pulse excitation pulsed laser deposition (PLD) method with a mask placed between the target and the substrate. Epitaxial growth of PMN-PT thin films was undertaken using the two-step growth method of PMN-PT film. The PMN-PT seed layer was deposited at 500 degrees C on the LSCO/CeO(2)/YSZ/Si, which temperature was the same as that used for LSCO deposition. The PMN-PT thin films were deposited on the PMN-PT seed layer at 600 degrees C, which enables growth of high-crystallinity PMN-PT films with smooth surfaces. We obtained optimum fabrication conditions of PMNPT film with micrometer-order thickness. Resultant films showed high crystallinity with full width at half maximum (FWHM) = 0.73 deg and 1.6 mum thickness. Electro-optic properties and the refractive index value were measured at 633 nm wavelength using the prism coupling method. The obtained refractive index was 2.59. The electro-optic coefficients r(13) and r(33) were determined by applying the electrical field between a semitransparent, thin top electrode of Pt and a bottom LSCO electrode. The electro-optic coefficient was r(13) = 17 pm/V at transverse electric field (TE) mode and r(33) = 55 pm/V at transverse magnetic field (TM) mode.


Asunto(s)
Cerámica/química , Cristalización/métodos , Membranas Artificiales , Silicio/química , Conductividad Eléctrica , Ensayo de Materiales , Óptica y Fotónica
15.
J Microsc ; 229(Pt 3): 396-401, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18331485

RESUMEN

We report on the fabrication of plasmonic devices with adjustable resonances in the visible portion employing a thermal lithography method. The genuine approach enables the fabrication of nanostructured pattern at a spatial resolution comparable to other nanofabrication techniques, but at significantly larger speeds and over extended spatial domains. The fabricated structures consisted in periodically arranged nanoholes in a silver thin film and supported localized plasmon resonance (LPR) in the vicinity of 370 nm. Results from measured spectral properties were in good agreement with simulations based on rigorous diffraction theory. The method was evaluated towards a potential application to realize large-scale meta-materials with effective negative refractive index in the visible.

16.
Surg Endosc ; 20(5): 830-3, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16544074

RESUMEN

Although hand-assisted laparoscopic surgery (HALS) is very common in various laparoscopic procedures, it is rarely used for retroperitoneal endoscopic adrenalectomy because of the small working area. The authors evaluate HALS in endoscopic adrenalectomy with respect to its use as a rescue procedure in complicated cases. In their department, 47 patients underwent endoscopic adrenalectomies between 1998 and 2004. Mainly because of complicated anatomy, three primary aldosteronism cases were converted to retroperitoneal HALS. This involved making an additional 6 cm skin incision, into which the surgeon's left hand was inserted, with the palm used to create a sufficient visual field and working area. The fingers were used for tactile sensation and blunt resection. For these three cases, successful retroperitoneal HALS in endoscopic adrenalectomy resulted in no mortality or morbidity. These findings indicate that this procedure is a feasible technique for complicated benign adrenal tumor cases.


Asunto(s)
Adrenalectomía/métodos , Endoscopía/métodos , Hiperaldosteronismo/cirugía , Laparoscopía/métodos , Espacio Retroperitoneal , Terapia Recuperativa/métodos , Estudios de Factibilidad , Femenino , Mano , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
17.
Cell Mol Life Sci ; 63(3): 285-300, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16389451

RESUMEN

Neutron diffraction provides an experimental method of directly locating hydrogen atoms in proteins, a technique complimentary to ultra-high-resolution [1, 2] X-ray diffraction. Three different types of neutron diffractometers for biological macromolecules have been constructed in Japan, France and the United States, and they have been used to determine the crystal structures of proteins up to resolution limits of 1.5-2.5 A. Results relating to hydrogen positions and hydration patterns in proteins have been obtained from these studies. Examples include the geometrical details of hydrogen bonds, H/D exchange in proteins and oligonucleotides, the role of hydrogen atoms in enzymatic activity and thermostability, and the dynamical behavior of hydration structures, all of which have been extracted from these structural results and reviewed. Other techniques, such as the growth of large single crystals, the preparation of fully deuterated proteins, the use of cryogenic techniques, and a data base of hydrogen and hydration in proteins, will be described.


Asunto(s)
Hidrógeno/química , Difracción de Neutrones , Proteínas/química , Agua/química , Biología , Deuterio/química , Medición de Intercambio de Deuterio , Difracción de Neutrones/instrumentación , Conformación Proteica
18.
Abdom Imaging ; 31(3): 326-31, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16333703

RESUMEN

BACKGROUND: We sought to validate computed tomographic virtual pancreatoscopy (CT-VP) created by multidetector row CT (MD-CT) in the clinical diagnosis of intraductal papillary mucinous neoplasm (IPMN) of the pancreas. METHODS: Five cases of pancreatic IPMNs were included in this study. A nasopancreatic drainage tube was inserted and the pancreatic duct was filled with contrast medium, after which an upper abdominal scan was performed by MD-CT. CT-VP and three-dimensional (3D) CT pancreatographic images were created using a workstation and compared with images by conventional diagnostic techniques. All cases were evaluated by endoscopic retrograde pancreatography (ERP) and three cases of main duct type were assessed by intraoperative real pancreatoscopy (RP). RESULTS: In the main duct cases, papillary projections in the main pancreatic duct and branch orifices were clearly detected by CT-VP. These lesions and structures were confirmed by intraoperative RP, and the CT-VP images were clearer than RP images. In branch cases, a surface-rendering method allowed protruding lesions to be clearly detected in the dilated branches. CONCLUSION: Compared with conventional ERP or RP, CT-VP and 3D-CT pancreatographic images were finer in quality, and the procedures were less invasive, faster, and less expensive. The potential shown by CT-VP with 3D-CT pancreatography in the clinical diagnosis of pancreatic IPMNs suggests that this approach may replace ERP in the near future.


Asunto(s)
Adenocarcinoma Mucinoso/diagnóstico por imagen , Adenocarcinoma Papilar/diagnóstico por imagen , Carcinoma Ductal Pancreático/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Anciano , Medios de Contraste , Diagnóstico Diferencial , Femenino , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Interpretación de Imagen Radiográfica Asistida por Computador
19.
Tissue Cell ; 37(1): 75-9, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15695179

RESUMEN

Striated microfilament bundles attaching to the plasma membrane of cytoplasmic bridges between spermatogenic cells are described in the black snail, Semisulcospira libertina. The bundles were occasionally observed in bridges connecting spermatogonia, spermatocytes and typical spermatids. Relations between bundles and centrioles could not be detected. The bundle had electron dense cross bands with a periodicity of approximately 200 nm, and attached to the membrane with almost right angle at the cross linker level. Phalloidin cytochemistry revealed that the bundle contained F-actin. In a case, a bundle connected two cytoplasmic bridges.


Asunto(s)
Citoesqueleto de Actina/ultraestructura , Citoplasma/ultraestructura , Caracoles/ultraestructura , Animales , Membrana Celular/ultraestructura , Masculino , Microscopía Electrónica de Transmisión , Espermátides/ultraestructura , Espermatocitos/ultraestructura , Espermatogonias/ultraestructura , Testículo/ultraestructura
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