Cost Analysis of Screening for IgA Nephropathy Using Novel Biomarkers

[Objectives] IgA nephropathy (IgAN) is the most common primary chronic glomerulonephritis and a major cause of end-stage kidney disease worldwide. Novel biomarkers, including the aberrantly glycosylated IgA1 and glycan-specific antibodies, could be useful in the diagnosis of IgAN. The aim of this study was to assess the cost analysis of IgAN screening using novel biomarkers in addition to the conventional screening compared with conventional screening alone. [Methods] To estimate the medical expense of each strategy related to renal disease for 40 years, we developed an analytical decision model. The decision tree started at “40 years of age with first-time hematuria.” It simulated 2 clinical strategies: IgAN screening using the novel biomarkers (group N) and conventional screening (group C). The analysis results were presented as medical expenses from a societal perspective. Discounting was not conducted. [Results] The expected medical expense per person for 40 years was ¥31.2 million (~$291 000) in group N and ¥33.4 million (~$312 000) in group C; hence, expense in group N was lower by ¥2.2 million (~$21 000). In group N, the expected value of IgAN increased by 5.67% points (N 48.44%, C 42.77%) and that of dialysis introduction decreased by 0.85% points (N 19.06%, C 19.91%). In the sensitivity analysis, expenses could be reduced in almost all cases except when renal biopsy using conventional screening was performed at the rate of 73% or higher. [Conclusion] Screening for IgAN using novel biomarkers would reduce renal disease–related expenses

Analytic solutions of nonlinear Cournot duopoly game

We construct a Cournot duopoly model with production externality in which reaction functions are unimodal. We consider the case of a Cournot model which has a stable equilibrium point. Then we show the existence of analytic solutions of the model. Moreover, we seek general solutions of the model in the form of nonlinear second-order difference equation

Development of an experimental rat model of hyperammonemic encephalopathy and evaluation of the effects of rifaximin

AbstractHepatic encephalopathy (HE) is a neuropsychiatric syndrome associated with hepatic dysfunction. However, the precise mechanism of HE is unclear. To elucidate the mechanism, we developed a new rat model of HE with coma using a combination of subcutaneous splenic transposition, partial hepatectomy and portal vein stenosis. In this model, blood ammonia levels increase in the postcaval vein over time and markedly increase in the cerebrospinal fluid (CSF). The distribution of ammonia in the various blood vessels in the HE model suggests that the origin of peripheral blood and CSF ammonia is the mesenteric veins that drain blood from the gastrointestinal tract. Behavioral analysis revealed decreased pain response, increased passivity, and decreased pinna and corneal reflexes, followed by the development of coma. The development of coma in this model was frequent and reproducible. Increased S100 calcium-binding protein B (S100B: a biomarker for brain injury) in venous blood, as well as damaged brain tissue, increased intracranial pressure and cerebral edema were observed in rats with coma. A very high correlation was observed between the blood ammonia concentration in the postcaval vein and the onset of coma. Rifaximin, a poorly absorbed antibiotic that targets gut flora, significantly improved symptoms of HE. Based on these results, our rat model appears to reflect the pathological state of HE associated with acute liver failure and may be a useful model for analysis of hyperammonemic encephalopathy

Sero-Epidemiological Study of Respiratory Syncytial Virus

Background: Respiratory syncytial virus (RSV) is one of the major viruses that cause respiratory infections in all generations, not only in neonates and infants. There is a limited number of reports on serological epidemiology of RSV subgroups A and B. Neutralizing test (NT) antibody reflects protective immunity but bothersome. Sero-epidemiological study should be performed using practical NT method. Methods: Two wild-type viruses subgroups A and B, isolated in 2013, and the Long strain was used as the challenge viruses. NT antibody with 100% inhibition of cytopathic effect (CPE) was examined. A total of 91 serum samples obtained from 0 to 12 years subjects without RSV infection who visited our hospital with some health problems and 121 sera obtained from healthy subjects in different age groups were used. Serological epidemiology of subgroups A and B was investigated in this study using new NT methods. Results: 1) A simple and practical NT method was developed. 2) The NT antibody titer was lowest in \u3c1 year of age (5 × 21.70 ± 2.03 against subgroup A and 5 × 20.85 ± 1.31 against subgroup B) and increased in 3 years of age or older, and high antibody titers were maintained during school age. 3) A slight difference was observed in the NT antibody titers against subgroups A and Bin young children \u3c3 years, but not after 3 years of age, reflecting the repeated infections. 4) Specific IgG antibody against RSV was measured. The IgG EIA values decreased with age. No association was observed between IgG EIA and NT titers. Conclusions: A simple NT assay method was developed in the present study. By the age of 3 years, high NT antibody titers were observed and maintained until 12 years. The IgG (EIA) values decreased with age. No association was observed between IgG (EIA) and NT titers

Psychosocial twin cohort studies in Japan: the Keio Twin Research Center (KoTReC)

The Keio Twin Research Center (KoTReC) was established in 2009 at Keio University to combine two longitudinal cohort projects — the Keio Twin Study (KTS) for adolescence and adulthood and the Tokyo Twin Cohort Project (ToTCoP) for infancy and childhood. KoTReC also conducted a two-time panel study of self-control and psychopathology in twin adolescence in 2012 and 2013 and three independent anonymous cross-sectional twin surveys (ToTcross) before 2012 — the ToTCross, the Junior and Senior High School Survey and the High School Survey. This article introduces the recent research designs of KoTReC and its publications