北川駿名誉教授の人となり

Orientador: Walmir de Freitas FilhoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de ComputaçãoResumo: Atualmente, cargas de diversos tipos de consumidores têm se tornado cada vez mais sensíveis a variações e interrupções de energia. Na maioria das vezes, falhas no fornecimento de energia são resultados da ocorrência de defeitos (faltas) em sistemas de distribuição de energia elétrica. Estes defeitos prejudicam a confiabilidade do fornecimento de energia e podem resultar em afundamento de tensão, interrupções momentâneas ou sustentadas e em elevados custos operacionais. Em vista disto, cada vez mais, os consumidores estão conscientes sobre o assunto e observa-se a necessidade da elaboração de soluções eficientes para melhorar os índices de confiabilidade e de qualidade do fornecimento de energia elétrica. Um dos métodos mais eficazes para melhorar os índices de confiabilidade e qualidade de energia elétrica em sistemas de distribuição consiste no desenvolvimento de técnicas rápidas e precisas de localização de defeitos na rede. Embora os métodos de localização de defeito empregados em alimentadores de distribuição ainda sejam rudimentares, a integração de técnicas de medição, comunicação, do conhecimento da configuração da rede e atuação de religadores em tempo real, além de dados provenientes dos Sistemas de Informações Geográficas em sistemas de distribuição permite o desenvolvimento de métodos mais eficientes, que exploram informações provenientes de diferentes locais da rede (informações distribuídas) e não apenas da subestação. Neste contexto, este trabalho explora métodos de localização de defeitos baseados em medidas de tensão provenientes de diferentes locais de modernos sistemas de distribuição. Três métodos foram investigados: (1) o primeiro, baseado na correspondência de valores de tensão, utiliza os parâmetros elétricos da rede e duas ou mais medidas de tensão ao longo do alimentador; (2) o segundo método, baseado na correspondência da corrente de falta, utiliza os parâmetros elétricos da rede e uma quantidade maior de medidas de tensão que o primeiro método; (3) finalmente, o terceiro método, baseado no mapeamento das zonas de tensão reduzida, não necessita do conhecimento completo dos parâmetros da rede, no entanto, é necessário utilizar uma maior quantidade de medidores que nos outros dois métodos. Os resultados dos testes realizados mostram que de acordo com a disponibilidade de medição de tensão ao longo do alimentador, um destes métodos pode ser escolhido para localizar o defeito de maneira eficazAbstract: Nowadays, loads from different classes of customers have become more sensitive to variations and interruptions from power supply. Frequently, failures in electrical energy delivery are caused by occurrences of faults in distribution systems. Such faults decrease the reliability of power delivery, increase operational costs and may result in power quality problems, such as voltage sag, short or long term outages. Since the customers consciousness is increasing, the need of efficient solutions to improve reliability and power quality indices is also increasing. One of the most efficient approaches to improve such indices in distribution systems is to develop fast and accurate fault location techniques for aerial feeders. Even though fault location methods dedicated to distribution feeders are still rudimentary, the recent integration of measurement, communication, real time knowledge of feeder configuration and reclosers trip and Geographic System Information allows the development of more efficient solutions, which explores information from different places from the grid (distributed information) and not only from the substation. In this context, this work explores fault location methods based on voltage measurements applied to modern distribution systems. Three methods were investigated: (1) the first one is based on matching voltage values, this method requires the network electrical parameters and two or more voltage meters installed along the feeder; (2) the second method is based on the correspondence of fault current, this method uses the network electrical parameters and a higher quantity of meters than the first method; (3) finally, the third method is based on the identification of low voltage zones, this method does not require network electrical parameters, however it needs a higher quantity of voltage meters than the other two methods. The test results show that according to the voltage measurement availability along the feeder, one of these methods can be chosen to efficiently locate the faultDoutoradoEnergia EletricaDoutora em Engenharia Elétric

Long-term outcome of islet transplantation on insulin-dependent diabetes mellitus: An observational cohort study

Aims/Introduction: Among 619 patients diagnosed as insulin‐dependent diabetes mellitus or type 1 diabetes at Kyoto University, Kyoto, Japan, seven patients were selected as the ITx group and 26 age‐matched patients with no endogenous insulin secretion were selected as the MDI/CSII group. Hemoglobin A1c, aspartate aminotransferase/alanine aminotransferase (AST/ALT) and creatinine were assessed retrospectively at 1, 2, 5 and 10 years for both groups; serum C‐peptide immunoreactivity was assessed for the ITx group. Major clinical events were also assessed. Results: Hemoglobin A1c improvement in ITx was significant at 1 year (8.4% [7.8–9.9%] at baseline to 7.1% [6.3–7.4%] in ITx vs 8.2% [7.4–9.8%] at baseline to 8.1% [7.3–9.5%] in MDI/CSII, P < 0.01 between groups), and was maintained at 2 years (7.4% [6.3–8.2%] vs 8.4% [7.4–9.6%], P = 0.11). The increase of stimulated C‐peptide immunoreactivity was significant at 1 year (0.57 ng/mL [0.26–0.99 ng/mL], P < 0.05 from baseline) and 2 years (0.43 ng/mL [0.19–0.67 ng/mL], P < 0.05), although it became insignificant thereafter. There was no significant difference in AST/ALT or creatinine at 10 years, although a transient AST/ALT elevation was observed in ITx. In regard to clinical events, the occurrence of severe hypoglycemia was 14% vs 31% (relative risk 0.46, P = 0.64), that of infectious disease was 43% vs 12% (relative risk 3.71, P = 0.09) and digestive symptoms was 43% vs 7.7% (relative risk 5.57, P = 0.05) in ITx vs MDI/CSII, respectively. No patient died in either group. Conclusions: The present findings showed that ITx was considered to contribute to the reduction of hypoglycemia and better glycemic control with tolerable, but attention‐requiring, risks over a period of 10 years compared with MDI/CSII

Reduced glycemic variability and flexible graft function after islet transplantation: A case report

To date, studies of patients with islet transplantation addressing intermittently scanned continuous glucose monitoring profile and the flexibility of the graft islet function under different doses of insulin administration, both of which reflect the real daily life of patients, are quite limited. Here, we report a case of a 46‐year‐old woman who received islet transplantation after kidney transplantation. The patient was followed up over a period of 2 years after initial islet transplantation. Our results show that intermittently scanned continuous glucose monitoring can be useful for monitoring the reduction of glycemic variability, and suggest the appropriate regulation of insulin secretion from graft islets during mixed‐meal test by using different doses of exogenous insulin administration. Additionally, during the 2‐year observational period, glucagon elevation was detected only at hypoglycemia, whereas the level was within the normal range at normoglycemia or hyperglycemia

Pretransplant serum hepatitis C virus RNA levels predict response to antiviral treatment after living donor liver transplantation.

[Background]Given the limited efficacy and high adverse event rate associated with treatment of recurrent hepatitis C after liver transplantation, an individualized treatment strategy should be considered. The aim of this study was to identify predictors of response to antiviral therapy for hepatitis C after living donor liver transplantation (LDLT) and to study the associated adverse events. [Methods]A retrospective chart review was performed on 125 hepatitis C virus (HCV)-positive LDLT recipients who received interferon plus ribavirin and/or peginterferon plus ribavirin therapy at Kyoto University between January 2001 and June 2011. [Results]Serum HCV RNA reached undetectable levels within 48 weeks in 77 (62%) of 125 patients, and these patients were defined as showing virological response (VR). Of 117 patients, 50 (43%) achieved sustained VR (SVR). Predictive factors associated with both VR and SVR by univariate analysis included low pretransplant serum HCV RNA levels, a non-1 HCV genotype, and low pretreatment serum HCV RNA levels. In addition, LDLT from ABO-mismatched donors was significantly associated with VR, and white cell and neutrophil counts before interferon therapy were associated with SVR. Multivariate analysis showed that 2 variables–pretransplant serum HCV RNA level less than 500 kIU/mL and a non-1 HCV genotype–remained in models of both VR and SVR and that an ABO mismatch was associated with VR. No variables with a significant effect on treatment withdrawal were found. [Conclusions]Virological response to antiviral therapy in patients with hepatitis C recurring after LDLT can be predicted prior to transplant, based on pretransplant serum HCV-RNA levels and HCV genotype. LDLT from ABO-mismatched donors may contribute to more efficacious interferon therapy

Percutaneous coronary intervention strategy for acute coronary syndrome caused by spontaneous coronary artery dissection for relieving ongoing ischemia—Case series and literature review

AbstractAlthough spontaneous coronary artery dissection (SCAD) is one of the causes of acute coronary syndrome (ACS) or sudden cardiac death, its standard management, especially primary percutaneous coronary intervention (PCI) in ACS patients with ongoing ischemia, has not been established. We experienced three ACS patients with SCAD who were treated with a different strategy of primary PCI. Each PCI strategy led to different clinical and procedural results. We describe here such PCI strategies and results, and also discuss the literature regarding primary PCI strategies for SCAD-induced ACS patients with ongoing ischemia.<Learning objective: SCAD is a cause of ACS. However, the treatment strategy of primary PCI for SCAD has not been fully investigated. We used different PCI strategies for three SCAD patients with ongoing ischemia. Our case series suggested that plain old balloon angioplasty is an acceptable option to avoid coronary stenting because the majority of patients were young menstruating women. Coronary vasospasm might be associated with SCAD. Treatment with vasodilators could be a potential pharmacological option for avoiding recurrence of SCAD.

Masked CKD in hyperthyroidism and reversible CKD status in hypothyroidism

IntroductionWhile it is well known that thyroid function may affect kidney function, the transition of the chronic kidney disease (CKD) status before and after treatment for thyroid disorders, as well as the factors affecting this change, remains to be explored. In the present study, we focused on the change in kidney function and their affecting factors during the treatment for both hyperthyroidism and hypothyroidism. Methods Eighty-eight patients with hyperthyroidism and fifty-two patients with hypothyroidism were enrolled in a retrospective and longitudinal case series to analyze the changes in kidney function and their affecting factors after treatment for thyroid disorders. Results Along with the improvement of thyroid function after treatment, there was a significant decrease in estimated glomerular filtration rate (eGFR) in hyperthyroidism (an average Delta eGFR of -41.1 mL/min/1.73 m(2)) and an increase in eGFR in hypothyroidism (an average Delta eGFR of 7.1 mL/min/1.73 m(2)). The multiple linear regression analysis revealed that sex, eGFR, free thyroxine (FT4) and free triiodothyronine (FT3) could be considered independent explanatory variables for Delta eGFR in hyperthyroidism, while age, eGFR, and FT3 were detected as independent explanatory variables in hypothyroidism. In addition, the stratification by kidney function at two points, pre- and post-treatment for thyroid disorders, revealed that 4.5% of the participants with hyperthyroidism were pre-defined as non-CKD and post-defined as CKD, indicating the presence of "masked" CKD in hyperthyroidism. On the other hand, 13.5% of the participants with hypothyroidism presented pre-defined CKD and post-defined non-CKD, indicating the presence of "reversible" CKD status in hypothyroidism. Conclusions We uncovered the population of masked CKD in hyperthyroidism and reversible CKD status in hypothyroidism, thereby re-emphasizing the importance of a follow-up to examine kidney function after treatment for hyperthyroidism and the routine evaluation of thyroid function in CKD patients as well as the appropriate hormone therapy if the patient has hypothyroidism

Multidimensional background examination of young underweight Japanese women: focusing on their dieting experiences

IntroductionThis study examines the background of underweight young women in Japan from multiple perspectives, focusing on whether they have ever dieted.MethodsA screening survey was administered to 5,905 underweight (BMI &lt; 18.5 kg/m2) women aged 18–29 years, who could report their birth weight recorded in their mother-child handbook. Valid responses were obtained from 400 underweight and 189 normal-weight women. The survey collected data regarding height, weight (BMI), body image and perception of weight, dieting experience, exercise habits from elementary school age onwards, and current eating habits. Additionally, five standardized questionnaires were used (EAT-26, eHEALTH, SATAQ-3 JS, TIPI-J, and RSES). The primary analysis was a comparative analysis (t-test/χ2)—with the presence or absence of underweight and diet experience as independent variables, and each questionnaire as a dependent variable.ResultsThe screening survey revealed that approximately 24% of the total population was underweight, with a low mean BMI. Of the respondents, more than half reported their body image as skinny and a small percentage as obese. Compared with the non-diet-experienced group (NDG), the diet-experienced group (DG) had a significantly higher proportion of past to current exercise habits. There was a significantly higher percentage of disagreement responses from the DG for weight and food gain than for the NDG. The NDG weighed significantly less than the DG in terms of birth weight, and lost weight easier than the DG. Additionally, the NDG was significantly more likely to agree with increasing weight and food intake. The NDG’s exercise habits were below 40% from elementary school age to the present, predominantly owing to a dislike for exercise and a lack of opportunity to implement it. In the standardized questionnaire, the DG was significantly higher for EAT-26, eHEALTH, SATAQ-3 JS, and Conscientiousness (TIPI-J), whereas the NDG was only significantly higher for Openness (TIPI-J).DiscussionThe results suggest the need for different health education programs for underweight women who desire to lose weight and experience dieting and for those who do not. This study’s results are reflected in the development of sports opportunities optimized for each individual, and in the development of measures to ensure adequate nutritional intake

Characterization of the novel mutant A78T-HERG from a long QT syndrome type 2 patient: Instability of the mutant protein and stabilization by heat shock factor 1

Background:The human ether-a-go-go-related gene (HERG) encodes the α-subunit of rapidly activating delayed-rectifier potassium channels. Mutations in this gene cause long QT syndrome type 2 (LQT2). In most cases, mutations reduce the stability of the channel protein, which can be restored by heat shock (HS). Methods: We identified the novel mutant A78T-HERG in a patient with LQT2. The purpose of the current study was to characterize this mutant protein and test whether HS and heat shock factors (HSFs) could stabilize the mutant protein. A78T-HERG and wild-type HERG (WT-HERG) were expressed in HEK293 cells and analyzed by immunoblotting, immunoprecipitation, immunofluorescence, and whole-cell patch clamping. Results: When expressed in HEK293 cells, WT-HERG gave rise to immature and mature forms of the protein at 135 and 155 kDa, respectively. A78T-HERG gave rise only to the immature form, which was heavily ubiquitinated. The proteasome inhibitor MG132 increased the expression of immature A78T-HERG and increased both the immature and mature forms of WT-HERG. WT-HERG, but not A78T-HERG, was expressed on the plasma membrane. In whole-cell patch clamping experiments, depolarizing pulses evoked E4031-sensitive HERG channel currents in cells transfected with WT-HERG, but not in cells transfected with A78T-HERG. The A78V mutant, but not A78G mutant, remained in the immature form similarly to A78T. Maturation of the A78T-HERG protein was facilitated by HS, expression of HSF-1, or exposure to geranyl geranyl acetone. Conclusions: A78T-HERG was characterized by protein instability and reduced expression on the plasma membrane. The stability of the mutant was partially restored by HSF-1, indicating that HSF-1 is a target for the treatment for LQT2 caused by the A78T mutation in HERG