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1.
Nat Commun ; 7: 11781, 2016 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-27283225

RESUMO

Two-dimensional electron gases at oxide surfaces or interfaces show exotic ordered states of matter, like superconductivity, magnetism or spin-polarized states, and are a promising platform for alternative oxide-based electronics. Here we directly image a dense population of randomly distributed ferromagnetic domains of ∼40 nm typical sizes at room temperature at the oxygen-deficient surface of SrTiO3, a non-magnetic transparent insulator in the bulk. We use laser-based photoemission electron microscopy, an experimental technique that gives selective spin detection of the surface carriers, even in bulk insulators, with a high spatial resolution of 2.6 nm. We furthermore find that the Curie temperature in this system is as high as 900 K. These findings open perspectives for applications in nano-domain magnetism and spintronics using oxide-based devices, for instance through the nano-engineering of oxygen vacancies at surfaces or interfaces of transition-metal oxides.

2.
Transplant Proc ; 46(4): 1071-3, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24815131

RESUMO

INTRODUCTION: Multiorgan procurement is not an easy procedure and requires special technique and training. Since sufficient donors are not available for on-site training in Japan, establishment of the educational program for multiorgan procurement is mandatory. MATERIALS AND METHODS: Development of e-learning and simulation using pigs are our main goals. E-learning contains three dimensional computer graphic (3DCG) animations of the multiorgan procurement, explanation of both donor criteria and procurement procedure, and self-assessment examination. To clarify the donor criteria, the risk factors to 3-month survival of the recipients were analyzed in 138 adult cases of liver transplantation. The 3DCG animation for liver procurement was developed, which was used in the lecture prior to the simulation on August 10, 2013. The results of the examination after this lecture (exam 2013) were compared with the results after the lecture without using animation in 2012 (exam 2012). The simulation was performed by 97 trainees divided into 9 teams, and the surveys were conducted. RESULTS: The risk factors for early outcome of the recipients were cold ischemia time (≥ 10 hours), Model for End-stage Liver Disease score (≥ 20), and donor age (≥ 55 years). Results of examination showed that overall percentage of the correct answers was significantly higher in exam 2013 than in exam 2012 (48.3% vs 32.7%; P = .0001). The survey after the simulation of multiorgan procurement revealed that most trainees thought that the simulation was useful and should be continued. CONCLUSION: The novel educational program could allow young surgeons to make precise assessments and perform the exact procedure in the multiorgan procurement.


Assuntos
Seleção do Doador/métodos , Educação de Pós-Graduação em Medicina/métodos , Hepatopatias/cirurgia , Transplante de Fígado/educação , Doadores de Tecidos , Coleta de Tecidos e Órgãos/educação , Fatores Etários , Animais , Isquemia Fria/efeitos adversos , Gráficos por Computador , Instrução por Computador , Currículo , Avaliação Educacional , Humanos , Hepatopatias/diagnóstico , Transplante de Fígado/efeitos adversos , Pessoa de Meia-Idade , Modelos Animais , Desenvolvimento de Programas , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Inquéritos e Questionários , Suínos , Resultado do Tratamento
3.
Transplant Proc ; 46(2): 640-3, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24656034

RESUMO

A 61-year-old Japanese woman, who had undergone hemodialysis because of chronic glomerulonephritis, received a living renal transplant from her ABO blood type-compatible spouse. HLA typing of A, B and DRB showed 3/6 mismatches. Complement-dependent cytotoxicity crossmatches, HLA antibody screening with the use of flow panel reactive antibody (PRA), and flow cytometry crossmatches (FCXM) were all negative. Tacrolimus, mycophenolate mofetil, methylprednisolone (MP), and basiliximab induction were used as the standard immunosuppressive therapy. After renal transplantation, her serum creatinine level favorably decreased, but urine output was not sufficiently obtained, contrary to our expectations. Doppler sonography revealed disappearance of diastolic arterial flow on postoperative day 2. The episode biopsy showed acute antibody-mediated rejection (AMR) based on the current Banff classification, although FCXM and flow PRA were still negative. To determine the cause of acute AMR, we expanded the HLA typing at high resolution levels to Cw, DQB1, and DPB1. Retrospective analysis of perioperative sera demonstrated the presence of low levels of donor-specific HLA IgG and moderate levels of IgM antibody against DQB1 before transplantation. There was an elevation of IgM antibody at the time of rejection, whereas IgG antibody showed no remarkable change. AMR was successfully treated with plasma exchange, low-dose intravenous immunoglobulin, high-dose intravenous MP pulse, and rituximab.


Assuntos
Autoanticorpos/imunologia , Rejeição de Enxerto/imunologia , Cadeias beta de HLA-DQ/imunologia , Neoplasias Renais/imunologia , Feminino , Citometria de Fluxo , Humanos , Imunossupressores/administração & dosagem , Pessoa de Meia-Idade
4.
Reprod Biomed Online ; 13(6): 801-6, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17169199

RESUMO

Fertilization failure (complete fertilization failure or low fertilization rates) after intracytoplasmic sperm injection (ICSI) can occur in rare cases. In the majority of these cases, the unfertilized oocytes are inactivated. Assisted oocyte activation was applied as a treatment option for a case of low fertilization rate as a clinical trial. A patient with a low fertilization rate (ranging from 0% to 33.3%; mean = 17.0%) after eight previous ICSI cycles at another hospital, was diagnosed with fertilization failure. The most likely cause of fertilization failure was failure of oocyte activation. Therefore, artificial oocyte activation by strontium treatment was combined with ICSI to achieve viable fertilized oocytes. Oocytes were stimulated with strontium (10 mM SrCl(2), 60 min) approximately 30 min after ICSl. Six injected oocytes were stimulated and all were then successfully fertilized. Two blastocysts were transferred into the uterus, resulting in a pregnancy and birth. A second pregnancy was achieved following implantation of two cryopreserved embryos (one blastocyst and one morula). In conclusion, strontium treatment was found to be an effective method for artificial oocyte activation in a case with a low fertilization rate after ICSI.


Assuntos
Infertilidade/terapia , Oócitos/efeitos dos fármacos , Injeções de Esperma Intracitoplásmicas/métodos , Estrôncio/farmacologia , Adulto , Transferência Embrionária , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Resultado da Gravidez
5.
Clin Nephrol ; 66(3): 202-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16995343

RESUMO

Patients with infective endocarditis (IE) often have renal complications which may include infarcts, abscesses and glomerulonephritis (GN). Furthermore, it is generally accepted that there is an association between IE and anti-neutrophil cytoplasmic antibody (ANCA). Here, we report the case of a 24-year-old man who developed rapidly progressive GN in the course of IE due to infection with alpha-streptococcus. The initial clinical manifestation of the condition was severe sacroiliitis without fever. Sandwich ELISA showed that the patient was positive for PR3-ANCA at low titer, and the classical complement pathway was also activated. Renal biopsy demonstrated several lesions: focal embolic GN, GN with immune deposits and focal and segmental crescentic necrotizing GN. Treatment with antibiotics and steroids led to eradication of the infection, and resolution of the renal disease was accompanied by immediate disappearance of PR3-ANCA and hypocomplementemia. During a 4-year follow-up period, no recurrence was observed. There have only been 7 case reports of GN associated with IE and PR3-ANCA in which the renal pathology has been described, and the current report is the first to document renal pathology in a patient with isolated pulmonic valve IE and PR3-ANCA. Moreover, this report is the first to show a change in renal biopsy findings in response to treatment. A review of the 7 literature cases and that of our patient showed that none involved pauci-immune GN. Hence, further studies are needed to clarify the prevalence of pauci-immune GN in ANCA-positive IE patients.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos/metabolismo , Endocardite Bacteriana/complicações , Glomerulonefrite/complicações , Rim/patologia , Mieloblastina/metabolismo , Valva Pulmonar/microbiologia , Adulto , Biópsia , Progressão da Doença , Ecocardiografia Transesofagiana , Endocardite Bacteriana/diagnóstico por imagem , Humanos , Rim/ultraestrutura , Masculino , Metanálise como Assunto
6.
Aliment Pharmacol Ther ; 21 Suppl 2: 111-5, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15943857

RESUMO

BACKGROUND: It has been reported that inhibitors of gastric acid secretion prevent bleeding after endoscopic mucosal resection for mucosal gastric neoplasm. However, uncertain whether an histamine2-receptor antagonist or proton-pump inhibitor is more effective. AIM: To evaluate prospectively the effectiveness of famotidine or omeprazole for ulcer management after endoscopic mucosal resection. METHODS: From July 2003 to October 2004, 57 patients were randomly assigned to famotidine or omeprazole for the management of endoscopic mucosal resection. Both drugs were given intravenously for the first 2 days, thereafter by mouth. The bleeding rates after endoscopic mucosal resection, the effects on the healing of endoscopic mucosal resection-induced ulceration, and cost-benefits were compared. RESULTS: Twenty-eight patients received famotidine and 29 received omeprazole. No significant difference was observed between the two groups in patient characteristics. The bleeding rates after endoscopic mucosal resection were not significantly different (18% vs. 14%) between the groups. Similarly, no differences were seen in the size of the endoscopic mucosal resection-induced ulceration at 1, 30 and 60 days after resection between groups. The total costs of anti-secretory agents demonstrated a significant cost-benefit to those treated with famotidine (10,420 yen vs. 17,782 yen). CONCLUSIONS: Famotidine is suggested as a better alternative to omeprazole for the management of endoscopic mucosal resection, as it showed a clear cost-benefit, and the healing results after endoscopic mucosal resection were similar for the two treatment strategies.


Assuntos
Endoscopia Gastrointestinal/efeitos adversos , Famotidina/uso terapêutico , Hemorragia Gastrointestinal/prevenção & controle , Antagonistas dos Receptores H2 da Histamina/uso terapêutico , Omeprazol/uso terapêutico , Hemorragia Pós-Operatória/prevenção & controle , Idoso , Antiulcerosos/economia , Antiulcerosos/uso terapêutico , Análise Custo-Benefício , Endoscopia Gastrointestinal/economia , Famotidina/economia , Feminino , Mucosa Gástrica , Hemorragia Gastrointestinal/economia , Antagonistas dos Receptores H2 da Histamina/economia , Humanos , Masculino , Omeprazol/economia , Hemorragia Pós-Operatória/economia , Estudos Prospectivos , Neoplasias Gástricas/economia , Neoplasias Gástricas/cirurgia , Úlcera Gástrica/economia , Úlcera Gástrica/prevenção & controle
7.
Clin Nephrol ; 63(5): 368-74, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15909596

RESUMO

We present the case of a 69-year-old man with nephrotic syndrome and renal insufficiency, who developed lobular glomerulonephritis. An electron microscopy examination of a renal biopsy showed microtubular structures of 24 nm in diameter in the subendothelial space and the paramesangial area. These deposits were PAS-positive and Congo red-negative, and revealed predominantly positive staining for kappa light chain. There was no evidence of diseases with highly organized glomerular deposits, such as amyloidosis, cryoglobulinemia, systemic lupus erythematosus or paraproteinemia. Therefore, the patient was diagnosed to have immunotactoid glomerulopathy (ITG). During a seven-year course he has not developed any disease known to be associated with organized glomerular immune deposits. Hence, we believe ITG occurred as a primary glomerular disease in this case. We also highlight cases of ITG with microtubular deposits that have been reported in Japan, compare these cases to previous reports, and show that the characteristics of the Japanese cases are male predominance; a high incidence of membranoproliferative glomerulonephritis (MPGN); a low incidence of monoclonal gammopathy and hematological malignancies and a higher incidence of hypocomplementemia.


Assuntos
Glomerulonefrite Membranoproliferativa/imunologia , Glomerulonefrite Membranoproliferativa/patologia , Imunoglobulina G/análise , Microtúbulos/ultraestrutura , Idoso , Alprostadil/uso terapêutico , Biópsia por Agulha , Análise Química do Sangue , Transfusão de Sangue , Terapia Combinada , Dilazep/uso terapêutico , Seguimentos , Glomerulonefrite Membranoproliferativa/terapia , Humanos , Imuno-Histoquímica , Japão , Testes de Função Renal , Masculino , Proteinúria/diagnóstico , Proteinúria/terapia , Medição de Risco , Índice de Gravidade de Doença , Resultado do Tratamento
8.
Transplant Proc ; 36(2 Suppl): 251S-256S, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15041348

RESUMO

Chronic CSA nephrotoxicity is the second most important diagnosis responsible for the late graft failure. CSA associated arteriolopathy (CAA) is a well-known lesion of chronic CSA nephrotoxicity. The clinicopathological characteristics and the significance of CSA nephrotoxicity have changed following reduction in CSA doses and implementation of monitoring of blood levels. Seventy-four CAA patients on CSA therapy were classified as functioning (n=30) or loss groups (n=44). There was no significant difference in severity of CAA. The concomitant lesion of chronic rejection, but not the severity of CAA, was the most important risk factor for graft loss. Among 54 recipients with focal segmental glomerulosclerosis lesions (FGS), 32 (59%) were diagnosed as CAA associated glomerulopathy (CAG). Eighteen of the 32 CAG patients lost their grafts upon follow-up. Decreasing the CSA dosage to maintain lower blood levels than the usually optimal concentrations, but not discontinuation of CSA, has been useful to retard the progression of graft dysfunction in half of 15 isolated pure CAG patients. Patients with increasing daily proteinuria exceeding 2 grams lost their graft function despite CSA reductions. CAA is not a specific lesion of chronic CSA nephrotoxicity; the FGS lesion is also a nonspecific lesion often seen in renal allografts. Isolated chronic CSA arteriolopathy of severe degree has a fairly good prognosis under controlled CSA therapy. The FGS lesion accompanying CAA is considered to be CSA-associated glomerulopathy. These data contribute to therapeutic plans for renal transplant patients during long-term CSA treatment.


Assuntos
Ciclosporina/toxicidade , Transplante de Rim/patologia , Transplante de Rim/fisiologia , Arteríolas/efeitos dos fármacos , Arteríolas/patologia , Doença Crônica , Sobrevivência de Enxerto/efeitos dos fármacos , Sobrevivência de Enxerto/fisiologia , Humanos , Imunossupressores/toxicidade , Artéria Renal/efeitos dos fármacos , Artéria Renal/patologia , Falha de Tratamento , Resultado do Tratamento
9.
Transplant Proc ; 36(2 Suppl): 461S-464S, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15041388

RESUMO

We investigated the clinical benefits of cyclosporine microemulsion preconcentrate (CyA-MEPC; Neoral) in 16 de novo renal transplant recipients. The dose of CyA-MEPC was managed from AUC(0-4h), with serial target values of AUC(0-4h) at 5000-->4000-->3000-->2000 ng. hr/mL. The frequency of acute rejection episodes was 25%. The decreased renal function reached a low value of 12.5%, and creatinine was stable. Therefore, setting the target AUC(0-4h) value in the early phase at 5000 ng.hr/mL is an effective strategy to prevent acute rejection episodes. The single dose of Neoral given immediately after the renal transplant was 6 mg/kg (making a daily dose of 12 mg/kg). Thereafter, the dose-normalized AUC(0-4h) was set at a constant value to 4 weeks posttransplant. At week 4, the single dose was decreased to 4 mg/kg twice daily (a daily dose of 8 mg/kg). From these studies a daily dose of 12 mg/kg is suggested to be the appropriate amount for the first dose immediately after transplant. The renal biopsy performed at 6 months posttransplant showed neither cyclosporine-induced renal impairments, nor findings of chronic rejection, suggesting that 2000 ng.hr/mL is an appropriate target AUC(0-4h) value in the maintenance phase. These results suggest that it is possible to set the target value of C2 monitoring in the maintenance phase to a value slightly lower than that proposed from other studies.


Assuntos
Ciclosporina/farmacocinética , Ciclosporina/uso terapêutico , Absorção Intestinal/fisiologia , Transplante de Rim/imunologia , Ácido Micofenólico/análogos & derivados , Adulto , Área Sob a Curva , Ciclosporina/administração & dosagem , Ciclosporina/sangue , Quimioterapia Combinada , Feminino , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/prevenção & controle , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/farmacocinética , Imunossupressores/uso terapêutico , Transplante de Rim/fisiologia , Masculino , Ácido Micofenólico/uso terapêutico , Período Pós-Operatório , Fatores de Tempo
18.
Hepatogastroenterology ; 48(40): 1195-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11490832

RESUMO

BACKGROUND/AIMS: Hemorrhagic gastric ulcer is a more serious disorder in elderly patients than in young patients. This study aimed to evaluate the efficacy of endoscopic treatment for hemorrhagic gastric ulcer in patients aged 80 years or more. METHODOLOGY: A total of 269 patients underwent endoscopic treatment for hemorrhagic gastric ulcer with hemoclipping and pure ethanol injection, either alone or in combination. These patients were divided into two groups: elderly (> or = 80 years old) and younger (< 80 years) groups. The clinical data, endoscopic findings and outcomes of endoscopic treatment were compared between these two groups. RESULTS: Patients in the elderly group had a significantly higher incidence of concomitant disease (73% vs. 23%), anemia (7.9 +/- 2.1 g/dL vs. 9.3 +/- 2.8 g/dL) and large ulcer (23% vs. 6%) compared with the younger group. However, all patients in the elderly group underwent endoscopic hemostasis successfully with no complications and no deaths. The rebleeding rate was not significantly different (8% vs. 4%) between the two groups. CONCLUSIONS: Elderly patients with hemorrhagic gastric ulcer have high incidences of severe ulcer disease and concomitant medical problems. Endoscopic hemostasis for hemorrhagic gastric ulcer is effective and safe, even for such elderly patients.


Assuntos
Endoscopia Gastrointestinal , Úlcera Péptica Hemorrágica/cirurgia , Úlcera Gástrica/complicações , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Feminino , Humanos , Masculino , Úlcera Péptica Hemorrágica/epidemiologia , Úlcera Gástrica/epidemiologia
20.
Gastrointest Endosc ; 53(4): 427-30, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11275881

RESUMO

BACKGROUND: Endoscopic hemoclipping is known to be highly effective as hemostatic treatment for upper gastrointestinal bleeding. However, the efficacy and safety of hemoclipping for Mallory-Weiss syndrome (MWS) have not been reported. Thus, the aim of the present study was to assess prospectively the usefulness of endoscopic hemoclipping for MWS bleeding. METHODS: This study was conducted from January 1994 to August 1999. Hemoclipping was performed when active bleeding (spurting, streaming or oozing), visible vessels or fresh adhesive clots were found on endoscopic examination. Patients who did not have any of these findings were conservatively treated. Follow-up endoscopy was performed within 24 hours, after 5 days and between 1 and 2 months after the procedure. RESULTS: MWS was diagnosed in a total of 58 patients during the study. Hemoclipping was performed in 26 patients and was technically successful in all cases. The average number of hemoclips used was 2.8 +/- 1.6 (range 1 to 8). The number of hemoclips required for hemostasis depended on the nature of the bleeding. No complications, recurrent bleeding, or deaths resulted. Follow-up endoscopy showed no evidence of hemoclip-induced tissue injury and no impairment of Mallory-Weiss tears. CONCLUSION: Endoscopic hemoclipping provided an effective and safe modality for obtaining hemostasis when bleeding is due to MWS.


Assuntos
Hemorragia Gastrointestinal/cirurgia , Gastroscopia/métodos , Hemostase Endoscópica/métodos , Síndrome de Mallory-Weiss/cirurgia , Feminino , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/patologia , Humanos , Masculino , Síndrome de Mallory-Weiss/patologia , Pessoa de Meia-Idade
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