Elucidating Dark Energy with Future 21 cm Observations at the Epoch of Reionization

We investigate how precisely we can determine the nature of dark energy such as the equation of state (EoS) and its time dependence by using future observations of 21 cm fluctuations at the epoch of reionization (6.8 <~ z <~ 10) such as Square Kilometre Array (SKA) and Omniscope in combination with those from cosmic microwave background, baryon acoustic oscillation, type Ia supernovae and direct measurement of the Hubble constant. We consider several parametrizations for the EoS and find that future 21 cm observations will be powerful in constraining models of dark energy, especially when its EoS varies at high redshifts.Comment: 35 pages, 12 figure

Determination of neutrino mass hierarchy by 21 cm line and CMB B-mode polarization observations

We focus on the ongoing and future observations for both the 21 cm line and the CMB B-mode polarization produced by a CMB lensing, and study their sensitivities to the effective number of neutrino species, the total neutrino mass, and the neutrino mass hierarchy. We find that combining the CMB observations with future square kilometer arrays optimized for 21 cm line such as Omniscope can determine the neutrino mass hierarchy at 2 sigma. We also show that a more feasible combination of Planck + POLARBEAR and SKA can strongly improve errors of the bounds on the total neutrino mass and the effective number of neutrino species to be Delta Sigma m_nu ~ 0.12 eV and Delta N_nu ~ 0.38 at 2 sigma.Comment: 10 pages, 3 figures, to appear in Phys. Lett.

Rationale and design of a randomized trial to test the safety and non‑inferiority of canagliflozin in patients with diabetes with chronic heart failure : the CANDLE trial

Background: Because type 2 diabetes mellitus is associated strongly with an increased risk of cardiovascular diseases, the number of patients with diabetes with chronic heart failure is increasing steadily. However, clinical evidence of therapeutic strategies in such patients is still lacking. A recent randomized, placebo-controlled trial in patients with type 2 diabetes with high cardiovascular risk demonstrated that the SGLT2 inhibitor, empagliflozin, reduced the incidence of hospitalization for heart failure. Because SGLT2 inhibitors cause a reduction in body weight and blood pressure in addition to improving glycemic control, they have the potential to exert beneficial effects on the clinical pathophysiology of heart failure. The aim of the ongoing CANDLE trial is to test the safety and non-inferiority of canagliflozin, another SGLT2 inhibitor, compared with glimepiride, a sulfonylurea agent, in patients with type 2 diabetes mellitus and chronic heart failure. Methods: A total of 250 patients with type 2 diabetes who are drug-naïve or taking any anti-diabetic agents and suffering from chronic heart failure with a New York Heart Association classification I to III will be randomized centrally into either canagliflozin or glimepiride groups (1: 1) using the dynamic allocation method stratified by age (<65, ≥65 year), HbA1c level (<6.5, ≥6.5 %), and left ventricular ejection fraction (<40, ≥40 %). After randomization, all the participants will be given the add-on study drug for 24 weeks in addition to their background therapy. The primary endpoint is the percentage change from baseline in NT-proBNP after 24 weeks of treatment. The key secondary endpoints after 24 weeks of treatment are the change from baseline in glycemic control, blood pressure, body weight, lipid profile, quality of life score related to heart failure, and cardiac and renal function. Discussion: The CANDLE trial is the first to assess the safety and non-inferiority of canagliflozin in comparison with glimepiride in patients with type 2 diabetes with chronic heart failure. This trial has the potential to evaluate the clinical safety and efficacy of canagliflozin on heart failure

Investigation for the efficacy of COVID-19 vaccine in Japanese CKD patients treated with hemodialysis

Background: Dialysis patients are predisposed to severe disease and have a high mortality rate in coronavirus disease 2019 (COVID-19) due to their comorbidities and immunocompromised conditions. Therefore, dialysis patients should be prioritized for vaccination. This study aimed to examine how long the effects of the vaccine are maintained and what factors affect antibody titers. Methods: Hemodialysis patients (HD group) and age- and sex-matched non-dialysis individuals (Control group), receiving two doses of BNT162b2 vaccine, were recruited through the Japanese Society for Dialysis Therapy (JSDT) Web site in July 2021. Anti-SARS-CoV-2 immunoglobulin (IgG) (SARS-CoV-2 IgG titers) was measured before vaccination, 3 weeks after the first vaccination, 2 weeks after the second vaccination, and 3 months after the second vaccination, and was compared between Control group and HD group. Factors affecting SARS-CoV-2 IgG titers were also examined using multivariable regression analysis and stepwise regression analysis (least AIC). In addition, we compared adverse reactions in Control and HD groups and examined the relationship between adverse reactions and SARS-CoV-2 IgG titers. Results: Our study enrolled 123 participants in the Control group (62.6% men, median age 67.0 years) and 206 patients in the HD group (64.1% men, median age 66.4 years). HD group had significantly lower SARS-CoV-2 IgG titers at 3 weeks after the first vaccination (p < 0.0001), 2 weeks after second vaccination (p = 0.0002), and 3 months after the second vaccination (p = 0.045) than Control group. However, the reduction rate of SARS-CoV-2 IgG titers between 2 weeks and 3 months after the second vaccination was significantly smaller in HD group than in Control (p = 0.048). Stepwise regression analysis revealed that dialysis time was identified as the significant independent factors for SARS-CoV-2 IgG titers at 2 weeks after the second vaccination in HD group (p = 0.002) and longer dialysis time resulted in higher maximum antibody titers. The incidences of fever and nausea after the second vaccination were significantly higher in the HD group (p = 0.039 and p = 0.020). Antibody titers in those with fever were significantly higher than those without fever in both groups (HD: p = 0.0383, Control: p = 0.0096). Conclusion: HD patients had significantly lower antibody titers than age- and sex-matched non-dialysis individuals over 3 months after vaccination. Dialysis time was identified as a factor affecting SARS-CoV-2 IgG titers in HD group, with longer dialysis time resulting in higher maximum SARS-CoV-2 IgG titers