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To elucidate the seroprevalence and rate of asymptomatic infection with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) in Japanese children, serological analysis was performed using serum samples collected from March 2020 to February 2023. A total of 1493 serum samples were collected during the first study period (March 2020 to February 2021). None of the serum samples was positive for SARS‐CoV‐2 antibody. In the second period (March 2021 to February 2022), seven of the 1055 patients (0.7%) experienced SARS‐CoV‐2 infection. The third period (March 2022 to February 2023) was divided into three terms: from March to June 30, 2022; from July to October 2022; and from November 2022 to February 2023. The seroprevalence gradually increased throughout this period, with rates of 6.0%, 18.6%, and 30.4% in the three terms, respectively. Pediatric cases of asymptomatic SARS‐CoV‐2 infection occurred after the surge of Omicron variants. Since none of the SARS‐CoV‐2 antibody‐positive patients had a previous history of coronavirus disease 2019, the seroprevalence rate in this study may represent the rate of asymptomatic infection. [ABSTRACT FROM AUTHOR]

Chemists have long sought to regulate the reactivity of H2, to yield hydride ions, hydrogen atoms, or electrons on demand. One source of inspiration for achieving this control is [NiFe]hydrogenase ([NiFe]H2ase), which reacts with H2 to form various hydrogen active species such as NiIII hydride species, NiII hydride species, and NiI low‐valent species. Chemists have attempted to synthesize these hydrogen active species not only as models for the active species of [NiFe]H2ase, but also as electron transfer catalysts. However, the synthesis of NiI complex directly from H2 has not been reported. This paper reports the first example of a single‐step synthesis of a NiI complex, via reaction of a NiII complex with H2, stable for over 3 months at room temperature and we further demonstrate a reductive coupling of acridinium ions as part of a reaction cycle. [ABSTRACT FROM AUTHOR]

Multisystem inflammatory syndrome in children (MIS‐C) was reported as a severe complication of coronavirus disease 2019; an infection with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), and was suggested to be associated with Kawasaki disease (KD) in terms of severe systemic inflammation and mucocutaneous symptoms. Because severe gastrointestinal symptoms and systemic shock are more frequently observed with MIS‐C, patients with mild MIS‐C might have been diagnosed with KD. In this study, titers of IgG antibodies against the SARS‐CoV‐2 S (S‐IgG) and N proteins (N‐IgG) were measured in 99 serum samples collected from patients with KD treated between January 2020 and December 2021 to evaluate the relationship between KD and SARS‐CoV‐2 infection. S‐IgG were detected in only one patient out of 99 patients. This patient had coronavirus disease 2019 (COVID‐19) 10 months before KD onset, and was unlikely MIS‐C. According to characters of S‐IgG and N‐IgG, the patients was unlikely infected with SARS‐CoV‐2 just before the onset of KD. In addition to this study, the 26th Nationwide Survey and previous studies showed an association between KD and SARS‐CoV‐2 to be unlikely. In conclusion, SARS‐CoV‐2 infection was not observed in patients with KD until Delta predominance in Japan by the method of detecting SARS‐CoV‐2 IgG. [ABSTRACT FROM AUTHOR]

This paper reports the first example of C−H arylation of benzene under mild conditions, using H2 as an electron source {turnover numbers (TONs)=0.7–2.0 for 24 h}. The reaction depends on a Rh‐based electron storage catalyst, and proceeds at room temperature and in aqueous solution. Furthermore, the H2 is inactive during the radical transfer step, greatly reducing unwanted side reactions. [ABSTRACT FROM AUTHOR]

Dioxygen-tolerant [NiFe] hydrogenases catalyze not only the conversion of H2 into 2H+ and 2e- but also the reduction of O2 to H2O. Chemists have sought to mimic such bifunctional catalysts with structurally simpler compounds to facilitate analysis and improvement. Herein, we report a new [NiFe]-based catalyst for O2 reduction via an O2 adduct. Structural investigations reveal the first example of a side-on iron(IV) peroxo complex. [ABSTRACT FROM AUTHOR]

Dioxygen-tolerant [NiFe] hydrogenases catalyze not only the conversion of H2 into 2H+ and 2e- but also the reduction of O2 to H2O. Chemists have sought to mimic such bifunctional catalysts with structurally simpler compounds to facilitate analysis and improvement. Herein, we report a new [NiFe]-based catalyst for O2 reduction via an O2 adduct. Structural investigations reveal the first example of a side-on iron(IV) peroxo complex. [ABSTRACT FROM AUTHOR]

Chemists have long sought to regulate the reactivity of H2, to yield hydride ions, hydrogen atoms, or electrons on demand. One source of inspiration for achieving this control is [NiFe]hydrogenase ([NiFe]H2ase), which reacts with H2 to form various hydrogen active species such as NiIII hydride species, NiII hydride species, and NiI low‐valent species. Chemists have attempted to synthesize these hydrogen active species not only as models for the active species of [NiFe]H2ase, but also as electron transfer catalysts. However, the synthesis of NiI complex directly from H2 has not been reported. This paper reports the first example of a single‐step synthesis of a NiI complex, via reaction of a NiII complex with H2, stable for over 3 months at room temperature and we further demonstrate a reductive coupling of acridinium ions as part of a reaction cycle. [ABSTRACT FROM AUTHOR]

Reported herein is an electrode for dihydrogen (H2) oxidation, and it is based on [NiFe]Hydrogenase from Citrobacter sp. S-77 ([NiFe]S77). It has a 637 times higher mass activity than Pt (calculated based on 1 mg of [NiFe]S77 or Pt) at 50 mV in a hydrogen half-cell. The [NiFe]S77 electrode is also stable in air and, unlike Pt, can be recovered 100 % after poisoning by carbon monoxide. Following characterization of the [NiFe]S77 electrode, a fuel cell comprising a [NiFe]S77 anode and Pt cathode was constructed and shown to have a a higher power density than that achievable by Pt. [ABSTRACT FROM AUTHOR]

Von blau zu rot: Die Struktur und die Lumineszenzeigenschaften des Gadolinium(III) ‐ Komplexes 1 wurden untersucht. Durch abwechselnde Bestrahlung und O2 ‐ Einwirkung kann die Lumineszenz von 1 in THF bei Raumtemperatur reversibel geschaltet werden, wobei sich die Emissionsfarbe ändert (siehe Bild). Dabei spielt die lichtinduzierte Phosphoreszenz von 1 eine Schlüsselrolle. [ABSTRACT FROM AUTHOR]

We provide confirmation of our proposed design principles for a H2 activation catalytic cycle by constructing a new catalyst. We have been able to obtain a crystal structure to confirm our proposition that a reduced, dinuclear species stores electrons from hydrogen molecules in a metal-metal bond. [ABSTRACT FROM AUTHOR]

We report the successful increase in performance of a fuel cell based on organometallic catalysis. An organometallic [NiIIRuIV] peroxo complex functions as cathode catalyst and was designed following mechanistic consideration of the cell. It was confirmed that the organometallic [NiIIRuIV] peroxo catalyst could function in the fuel cell with a 240 % increase in power output over our previous systems. This organometallic catalyst can act in both solid and solution phases and allows observation of the mechanism, hence providing us further opportunity for future improvement. [ABSTRACT FROM AUTHOR]

ABSTRACT Severe pneumonia and leukocytosis are characteristic, frequently observed, clinical findings in pediatric patients with pandemic A/H1N1/2009 influenza virus infection. The aim of this study was to elucidate the role of cytokines and chemokines in complicating pneumonia and leukocytosis in patients with pandemic A/H1N1/2009 influenza virus infection. Forty-seven patients with pandemic A/H1N1/2009 influenza virus infection were enrolled in this study. Expression of interleukin (IL)-10 ( P = 0.027) and IL-5 ( P = 0.014) was significantly greater in patients with pneumonia than in those without pneumonia. Additionally, serum concentrations of interferon-γ ( P = 0.009), tumor necrosis factor-α ( P = 0.01), IL-4 ( P = 0.024), and IL-2 ( P = 0.012) were significantly lower in pneumonia patients with neutrophilic leukocytosis than in those without neutrophilic leukocytosis. Of the five serum chemokine concentrations assessed, only IL-8 was significantly lower in pneumonia patients with neutrophilic leukocytosis than in those without leukocytosis ( P = 0.001). These cytokines and chemokines may play important roles in the pathogenesis of childhood pneumonia associated with A/H1N1/2009 influenza virus infection. [ABSTRACT FROM AUTHOR]

The monitoring of active human herpesvirus 6 (HHV-6) B infection is important for distinguishing between the reactivation and latent state of the virus. The aim of this present study is to develop a quantitative reverse transcription polymerase chain reaction (RT-PCR) assay for diagnosis of active viral infection. Primers and probes for in house quantitative RT-PCR methods were designed to detect the three kinetic classes of HHV-6B mRNAs (U90, U12, U100). Stored PBMCs samples collected from 10 patients with exanthem subitum (primary HHV-6B infection) and 15 hematopoietic stem cell transplant recipients with HHV-6B reactivation were used to evaluate reliability for testing clinical samples. Excellent linearity was obtained with high correlation efficiency between the diluted RNA (1-100 ng/reaction) and Ct value of each gene transcript. The U90 and U12 gene transcripts were detected in all of the peripheral blood mononuclear cells (PBMCs) samples collected in acute period of primary HHV-6B infection. Only one convalescent PBMCs sample was positive for the U90 gene transcript. Additionally, the reliability of HHV-6B quantitative RT-PCRs for diagnosis of viral reactivation in hematopoietic transplant recipients was evaluated. Relative to virus culture, U90 quantitative RT-PCR demonstrated the highest assay sensitivity, specificity, positive predictive value, and negative predictive value. Thus, this method could be a rapid and lower cost alternative to virus culture, which is difficult to perform generally, for identifying active HHV-6B infection. J. Med. Virol. 84:1388-1395, 2012. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Rotavirus (RV) antigenemia has been reported in patients with gastroenteritis; however, the exact mechanism remains unclear. In order to elucidate the mechanism of RV antigenemia, an association between RV antigenemia and matrix metalloproteinase (MMP) were analyzed. The object of this study was to elucidate the role of MMPs and tissue inhibitors of metalloproteinases (TIMPs) in the pathogenesis of RV antigenemia. Forty children admitted to hospital with RV gastroenteritis were enrolled in this study. Paired serum samples were collected at the time of admission and discharge. Enzyme-linked immunosorbent assays (ELISA) were used to detect serum concentrations of viral antigens, MMP-1, -2, -9, -13, TIMP -1, and -2. Cytokines were measured using flow cytometric beads array. RV antigens were significantly higher in serum collected at the time of admission than discharge ( P < 0.001). MMP-9 concentrations were significantly higher in serum collected at the time of admission than discharge ( P < 0.001). MMP-2 concentrations were significantly lower in serum collected at the time of admission than discharge ( P < 0.001). A weak but a significantly positive association ( P = 0.034) was observed between RV antigen and MMP-9 in serum collected at the time of admission, and inverse association was observed between RV antigen and MMP-2. In addition, a weak but significantly positive association ( P = 0.002) was observed between IL-6 and MMP-9. These data suggest that MMPs may contribute to the pathogenesis of RV antigenemia. J. Med. Virol. 84:986-991, 2012. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

ABSTRACT The aims of this study were to elucidate the kinetics of Epstein-Barr virus (EBV) DNA load in serially collected peripheral blood mononuclear cells of patients with primary EBV infection, and to determine the correlated host factors. Blood samples were collected from 24 patients with primary EBV infection. EBV DNA copy numbers were measured using real-time polymerase chain reaction. Based on the kinetics of EBV DNA load, the 24 patients were divided into two groups: rapid regression and slow regression. Eighteen of the 24 patients (75%) were included in the slow regression and 6 (25%) in the rapid regression group. No statistically significant differences were observed between the two groups in clinical features and laboratory findings. However, acute phase (3 to 10 days after the onset of the illness) serum samples from six children in the slow regression and four in the rapid regression group revealed significantly higher serum interleukin (IL)-1β ( P= 0.018), IL-12 ( P= 0.009), tumor necrosis factor-α ( P= 0.019), interferon-inducible protein 10, and monokine induced by interferon γ concentrations in the rapid regression than the slow regression group. On the other hand, sera from six children in the slow regression and four in the rapid regression group in the convalescent phase (14 to 21 days after the onset of the illness) showed no statistically significant differences between the two groups in these biomarker concentrations. Based on this, it was concluded that the kinetics of EBV DNA load can be divided to two different patterns after primary EBV infection, and immune response might be associated with viral clearance. [ABSTRACT FROM AUTHOR]

Two genetic diagnosis systems using reverse transcription-loop-mediated isothermal amplification (RT-LAMP) technology were evaluated: one for detecting the HA gene of the pandemic influenza A/H1N1 2009 virus (H1pdm RT-LAMP) and the other for detecting the matrix gene of the influenza A virus (TypeA RT-LAMP). The competence of these two RT-LAMP assay kits for the diagnosis of the pandemic influenza A/H1N1 2009 virus was compared using real-time RT-PCR assays developed recently on viruses isolated and clinical specimens collected from patients with suspected infection. TypeA RT-LAMP and H1pdm RT-LAMP showed almost the same sensitivity as real-time RT-PCR for viruses isolated. The sensitivity and specificity of TypeA RT-LAMP and H1pdm RT-LAMP were 96.3% and 88.9%, respectively, for clinical specimens. Considering that the ability of the two RT-LAMP assay kits for detection of the pandemic influenza A/H1N1 2009 virus was comparable to that of the real-time RT-PCR assays, and that the assays were completed within 1 hr and did not require any expensive equipment, these two RT-LAMP assays are promising rapid diagnostic tests for the pandemic influenza A/H1N1 2009 virus at the hospital bedside. J. Med. Virol. 83:10-15, 2011. © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Examines the application of tissue engineering in oral implant surgery in Tokyo, Japan. Model of sinus augmentation procedure in rabbit; Evaluation of soft tissue management; Response of the gingiva and the peri-implant mucosa.

We present a case of primary Epstein-Barr virus (EBV) infection with erythema multiforme. A 1-year-old Japanese boy presented with skin eruptions, including typical target lesions and a low-grade fever. Just before the skin biopsy, 95 copies/μg DNA of EBV genome was detected in peripheral blood mononuclear cells, which subsequently increased to 6,834 copies/μg DNA. Skin tissue collected from the skin lesion showed the typical pathologic findings of erythema multiforme. EBV-encoded small nuclear RNA signals were not detected in the skin tissue by in situ hybridization. [ABSTRACT FROM AUTHOR]

Der Bau einer Brennstoffzelle mit der [NiFe]Hydrogenase (H2ase) S ‐ 77 als Wasserstoffanode wird von P. Ogo et al. in der Zuschrift auf S. 9041 ff. vorgestellt. Die Massenaktivität des Enzyms ist mehr als 600 ‐ mal größer als die von Platin, es ist an Luft stabil und kann nach Vergiftung durch CO zurückgewonnen werden. [ABSTRACT FROM AUTHOR]

The construction of a fuel cell using the [NiFe]hydrogenase (H2ase) S‐77 as the hydrogen anode is described by P. Ogo et al. in their Communication on page 8895 ff. The enzyme has a mass activity that is over 600 times greater than that of platinum, is stable to air, and can be recovered after CO poisoning. [ABSTRACT FROM AUTHOR]

An ingENious spin on fuel cells The cover picture shows a gENie watching an organometallic fuel cell to observe its reaction mechanism. In their Full Paper on p.   1368 ff., T. Hibino, S. Ogo et   al. describe an organometallic [NiIIRuIV] peroxo catalyst that functions as the cathode in a fuel cell with a 240 % increase in power output over their previous systems. The organometallic catalyst is active in both solid and solution phases and allows for observation of the mechanism, providing opportunity for further improvemENt to the hydrogEN economy. [ABSTRACT FROM AUTHOR]

Dioxygen-tolerant [NiFe] hydrogenases catalyze not only the conversion of H2 into 2H+ and 2e- but also the reduction of O2 to H2O. Chemists have sought to mimic such bifunctional catalysts with structurally simpler compounds to facilitate analysis and improvement. Herein, we report a new [NiFe]-based catalyst for O2 reduction via an O2 adduct. Structural investigations reveal the first example of a side-on iron(IV) peroxo complex. [ABSTRACT FROM AUTHOR]

Dioxygen-tolerant [NiFe] hydrogenases catalyze not only the conversion of H2 into 2H+ and 2e- but also the reduction of O2 to H2O. Chemists have sought to mimic such bifunctional catalysts with structurally simpler compounds to facilitate analysis and improvement. Herein, we report a new [NiFe]-based catalyst for O2 reduction via an O2 adduct. Structural investigations reveal the first example of a side-on iron(IV) peroxo complex. [ABSTRACT FROM AUTHOR]