Phase Transformation of Metastable Cu2ZnGeO4 with a Wurtz-Kesterite Structure at Elevated Temperatures.

The thermal stability and high-temperature phase transformation of metastable Cu2ZnGeO4 were investigated in an Ar atmosphere by thermogravimetry, differential thermal analysis, and high-temperature X-ray diffraction. Three Cu-deficient CuI2-xZnGeO4-2/x phases with a wurtzite-related structure were observed, with varying amounts of copper deficiency. The metastable Cu2ZnGeO4 was stable at approximately 275 °C and transformed into intermediate phases. The intermediate phases had a wurtz-kesterite structure with a small number of copper and oxygen vacancies, which later transformed into a high-temperature phase at approximately 425 °C. The crystal structure of the high-temperature phase was assumed to be a deficient wurtzite-related structure with hexagonal closely packed oxygen and deficient copper sites on the order of tens of a percent. The high-temperature phase decomposed into stable Cu2O, GeO2, and Zn2GeO4 phases above 550 °C. The mechanism for the formation of the phase with a large amount of copper deficiency is discussed, leading to an understanding of the formation process for the copper-deficient phase of complex compounds containing monovalent copper.

Molecular typing, antibiotic susceptibility, and biofilm production in nonencapsulated Streptococcus pneumoniae isolated from children in Japan.

The prevalence of nonencapsulated Streptococcus pneumoniae (NESp) has increased with the introduction of pneumococcal conjugate vaccines in children; however, the bacteriological characteristics of NESp have not been sufficiently clarified. In this study, NESp strains isolated from the nasopharyngeal carriage of children from four nursery schools in Japan were analyzed for molecular type, antibiotic susceptibility, and biofilm productivity. A total of 152 putative S. pneumoniae strains were identified by optochin-susceptibility analysis, of which 21 were not serotypeable by slide agglutination, quellung reaction, or multiplex PCR. Among these 21 strains, three were lytA-negative and, therefore, not S. pneumoniae. The remaining 18 strains were positive for lytA, ply, pspK, and bile solubility and were confirmed as NESp. Therefore, the isolation rate of NESp in the S. pneumoniae strains in this study was 12.0% (18/149). Molecular-typing analyses classified five strains as two existing sequence types (STs; ST7502 and ST7786), and 13 strains formed four novel STs. Horizontal spread was suspected, because strains with the same ST were often isolated from the same nursery school. The NESp isolates were generally susceptible to most antimicrobials, with the exception of macrolides; however, all isolates possessed more than one abnormal penicillin-binding protein gene. Furthermore, NESp strains were more effective than encapsulated counterparts at forming biofilms, which showed obvious differences in morphology. These data indicated that NESp strains should be continuously monitored as emerging respiratory pathogens.

Characterization of Influenza A(H1N1)pdm09 Viruses Isolated in the 2018-2019 and 2019-2020 Influenza Seasons in Japan.

The influenza A(H1N1)pdm09 virus that emerged in 2009 causes seasonal epidemic worldwide. The virus acquired several amino acid substitutions that were responsible for antigenic drift until the 2018-2019 influenza season. Viruses possessing mutations in the NA and PA proteins that cause reduced susceptibility to NA inhibitors and baloxavir marboxil, respectively, have been detected after antiviral treatment, albeit infrequently. Here, we analyzed HA, NA, and PA sequences derived from A(H1N1)pdm09 viruses that were isolated during the 2018-2019 and 2019-2020 influenza seasons in Japan. We found that A(H1N1)pdm09 viruses possessing the D187A and Q189E substitutions in HA emerged and dominated during the 2019-2020 season; these substitutions in the antigenic site Sb, a high potency neutralizing antibody-eliciting site for humans, changed the antigenicity of A(H1N1)pdm09 viruses. Furthermore, we found that isolates possessing the N156K substitution, which was predicted to affect the antigenicity of A(H1N1)pdm09 virus at the laboratory level, were detected at a frequency of 1.0% in the 2018-2019 season but 10.1% in the 2019-2020 season. These findings indicate that two kinds of antigenically drifted viruses-N156K and D187A/Q189E viruses-co-circulated during the 2019-2020 influenza season in Japan.

Salivary cortisol monitoring: determination of reference values in healthy children and application in asthmatic children.

Venipuncture testing of adrenocortical function in asthmatic infants and young children receiving inhaled corticosteroids can raise cortisol levels and mask physiological responses. This study aimed to establish reference ranges for salivary cortisol levels and evaluate the safety and effects of jet-nebulized budesonide inhalation suspension (BIS) on salivary cortisol levels and patient outcomes in infants and young children with mild or persistent asthma. Reference salivary cortisol levels were determined in healthy children aged 6 months to 4 years old. A 12-week multicenter, randomized, parallel-group, open-label study was performed involving 53 age-matched asthmatic children who received either 0.5 mg/day of BIS or 40-60 mg/day of cromolyn sodium inhalation suspension (CIS) via compressor nebulizer. The effective measuring range of salivary cortisol concentration in asthmatic children was 0.12-3.00 micrograms/dL. The upper and lower limits of the reference range were 0.827 and 0.076 micrograms/dL, respectively. No significant difference was seen from baseline through week 12 in the CIS and BIS groups. BIS was safe in these patients, with no inhibitory effects on adrenocortical function. Salivary cortisol measurement offers a useful and accurate tool for testing adrenocortical function in infants and young children. Longer-term studies that incorporate testing of the hypothalamic-pituitary-adrenal axis are warranted to confirm our findings.

Antigenic variants of influenza B viruses isolated in Japan during the 2017-2018 and 2018-2019 influenza seasons.

BACKGROUND: Here, we genetically and antigenically analyzed influenza B viruses (IBVs) isolated in Japan during the 2017-2018 and 2018-2019 influenza seasons. METHODS: A total of 68 IBVs (61 B/Yamagata/16/88-like [B/Yamagata]-lineage and 7 B/Victoria/2/87-like [B/Victoria]-lineage) were antigenically and genetically characterized by using hemagglutination inhibition (HI) assays and phylogenetic analysis, respectively. The susceptibility of IBVs to neuraminidase (NA) inhibitors was assessed by using a fluorescence-based NA inhibition assay. RESULTS: All 61 B/Yamagata-lineage isolates were genetically closely related to B/Phuket/3073/2013, the vaccine strain for these two seasons. Eleven B/Yamagata-lineage isolates tested were antigenically similar to B/Phuket/3073/2013 by the HI test. Seven B/Victoria-lineage isolates were genetically closely related to B/Texas/02/2013, the WHO-recommended vaccine strain for the 2017-2018 season; however, they were antigenically distinct from B/Texas/02/2013 with an eightfold or 16-fold difference in HI titer. Of these 7 isolates, 4 possessed a two-amino-acid deletion at positions 162 and 163 in hemagglutinin (HA) and the other 3 had a three-amino-acid deletion at positions 162-164 in HA. Importantly, the variants with the three-amino-acid deletion appeared to be antigenically different from the B/Colorado/06/2017 virus with the two-amino-acid deletion, the vaccine strain for the 2018-2019 season with a fourfold or eightfold difference in HI titer. One B/Yamagata-lineage isolate carrying a G407S mutation in its NA showed a marked reduction in susceptibility to zanamivir, peramivir, and laninamivir. CONCLUSIONS: These results highlight the need for continued monitoring for the prevalence of the antigenic variant with the three-amino-acid deletion and the variant with reduced NA inhibitor susceptibility.

Influenza A variants with reduced susceptibility to baloxavir isolated from Japanese patients are fit and transmit through respiratory droplets.

Here we report the isolation of the influenza A/H1N1 2009 pandemic (A/H1N1pdm) and A/H3N2 viruses carrying an I38T mutation in the polymerase acidic protein-a mutation that confers reduced susceptibility to baloxavir marboxil-from patients before and after treatment with baloxavir marboxil in Japan. These variants showed replicative abilities and pathogenicity that is similar to those of wild-type isolates in hamsters; they also transmitted efficiently between ferrets by respiratory droplets.

Diarrhea as a minor adverse effect due to oral polio vaccine.

Using the adverse events monitoring system of Japan, we observed diarrhea cases in approximately 10% of patients who received oral poliovirus vaccine (OPV). This study was conducted to investigate whether diarrhea among children aged 0 to 1 is caused by OPV or by other factors such contact at the doctor's office and/or with others outside the home. We conducted a survey of the health of children after regular health check-ups and after the administration of the OPV. The data from the health check-ups were used as a control for the OPV case group. We compared the first-OPV dose vaccination group as well as the second-OPV dose vaccination group to the health check-up group. For cases of diarrhea, the odds ratio of the OPV group to the health check-up group was 1.776. Our findings strongly suggest that post-OPV cases of mild diarrhea are closely related to the administration of the OPV.

Synthesis, structure, and fluorescence properties of a calcium-based metal-organic framework.

The solvothermal reaction of a mixture of calcium acetylacetonate and 1,4-naphthalenedicarboxylic acid (H2NDC) in a solution containing ethanol and distilled water gave rise to a metal-organic framework (MOF), {(H3O+)2[Ca(NDC)(C2H5O)(OH)]}4·1.1H2O. This MOF possesses a new structure composed of calcium clusters and H2NDC linker anions and shows a unique fluorescence property; it exhibits a fluorescence peak at 395 nm (λ ex = 350 nm) at room temperature, which is blue-shifted compared with that exhibited by the free H2NDC ligand. One of the possible mechanisms for this fluorescence is likely attributable to a ligand-to-metal charge transfer (LMCT) transition and is the first example of a calcium-based MOF exhibiting blue-shifted fluorescence due to LMCT.

An epidemiological study on Japanese autism concerning routine childhood immunization history.

To assess the causal association of autism with measles, mumps, and rubella (MMR) vaccine versus that with monovalent measles, mumps, and rubella immunization, a 1:2 sex-adjusted logistic regression analysis was conducted using data on subjects who were growing up in the Tokyo area between 1988 and 1992. When MMR immunization was used as a reference, monovalent measles immunization (odds ratio [OR] = 5.33, 99% confidence interval [CI]: 1.03-27.74), non-mumps immunization (OR = 8, 99%CI: 1.33-48.2), and non-rubella immunization (OR = 8.57, 99%CI: 1.30-56.4) with development of autistic spectrum disorders (ASD) were significantly increased. These results suggest a decreased risk of developing ASD with MMR compared to monovalent antigens. However, our findings may reflect potential selection bias due to requiring written consent, possible delayed vaccination in suspected autism cases, and small sample size (case = 21). For the case group and the control group, immunization completeness rate of each antigen, regardless of the timing of immunization, was 90.5% versus 100% in measles, 42.9% versus 78.6% in mumps (P < 0.01), 52.3% versus 83.3% in rubella (P < 0.01), 14.3% versus 45.2% in varicella (P < 0.01), 100% versus 90.5% in polio>2, 100% versus 97.6% in Diphtheria (D), pertussis, and tetanus (T)>3, 85.7% versus 66.7% in DT, 95.2% versus 92.9% in BCG, and 52.4% versus 81.0% in Japanese encephalitis>3 (P<0.01). Only two case subjects and four control subjects received their measles, mumps, and rubella immunizations separately, suggesting that few Japanese parents might have had concerns about the safety of MMR vaccine. A nation-wide study would be a practical measure to scientifically judge the safety of MMR and other routine childhood immunizations.

Wavelength dependence of polyyne preparation by liquid-phase laser ablation using pellet targets.

The amount of polyynes produced by Nd:YAG laser (355, 532, and 1064 nm) ablation of fullerene and graphite pellet targets was the largest for 1064 nm ablation, contrary to the powder target in the previous report. This result is believed to come from the difference in the main polyyne-production area in liquids in the optical cell, depending on the pellet and powder targets.