Publications by authors named "Kazushi Motomura"
Background: The reddening of the face and neck following alcohol consumption is known as Asian flush. Although genetic factors related to Asian flush have been reported to be inversely associated with duration of sleep, no study has reported an association between Asian flush and sleep satisfaction.
Methods: A cross-sectional study of 3823 Japanese people, aged 20 to 64 years was conducted.
Article Synopsis
- The COVID-19 pandemic led to a significant decline in RSV infections in 2020, but in 2021, an unusual spike and irregular seasonal patterns were observed globally, including in Osaka, Japan.
- By 2022, the epidemic size returned to normal, yet the onset timing of RSV infections remained unpredictable for 2022 and 2023.
- Attempts to forecast the 2023 RSV epidemic using historical data were unsuccessful, indicating that the seasonal patterns of RSV are still disrupted post-pandemic and that future monitoring is necessary.
Article Synopsis
- Despite the introduction of the rubella vaccine in 1977, rubella and congenital rubella syndrome (CRS) persist in Japan, highlighting flaws in the current immunization strategy.
- Universal immunization improved vaccine coverage and reduced rubella cases, but outbreaks occurred in 2012-2013 and 2018-2019 due to imported viruses and unvaccinated males.
- The study suggests that a single-dose vaccination is insufficient to fully prevent infections and CRS, emphasizing the need for a second dose to close immunization gaps and avoid future outbreaks.
Article Synopsis
- * A study involving 8,096 men over a median of 4 years found that lower serum albumin levels were associated with a higher likelihood of being underweight and experiencing height loss.
- * The findings suggest that healthy hyponutrition (low serum albumin and underweight status) is a significant risk factor for height loss, providing insights into the factors contributing to this issue among Japanese men.
Article Synopsis
- Sapovirus (SaV) is a nonenveloped RNA virus responsible for acute gastroenteritis, primarily affecting children, and currently lacks an effective vaccine.
- The study found that the VP1 capsid protein, which forms the virus's outer shell, has shown strong sequence conservation in the GI.1 genotype over 40 years, while the GI.2 genotype varied more widely.
- The research highlights a unique evolutionary mechanism preserving the VP1 P2 subdomain in GI.1, providing insights that could aid in future vaccine development against SaV.
Article Synopsis
- Human norovirus is a leading cause of acute gastroenteritis in all age groups, and this study focused on genetic variations of norovirus GI strains in hospitalized children in Chiang Mai, Thailand, from 2015 to 2021.
- A total of 2829 stool samples were analyzed, revealing that only 12 (0.4%) were positive for norovirus GI, with 58.3% of these identified as recombinant strains.
- The study found significant genetic diversity among the strains, indicating a complex landscape of both recombinant and non-recombinant norovirus GI strains contributing to gastroenteritis in the region. *
Article Synopsis
- Measles is a highly contagious viral disease that has caused significant infant mortality in developing countries, but Japan successfully eliminated it by improving vaccination and surveillance systems starting in 1978 and achieving elimination in 2015.
- Between 1982 and 2021, a comprehensive analysis of measles cases in Osaka Prefecture showed that while vaccination rates increased, the average age of susceptible individuals rose, and cases shifted from infants to young adults.
- Despite high vaccination rates and seroprevalence, a decline in antibody levels due to low measles incidence has led to rising vaccine failures, highlighting the need for booster doses to maintain immunity.
Article Synopsis
- Wastewater-based epidemiology (WBE) proved crucial during the COVID-19 pandemic as patients avoided clinics, allowing for ongoing tracking of enteric viruses in communities.
- A study was conducted analyzing raw sewage from Japan's Tohoku and Kansai regions from 2019 to 2022, focusing on major acute gastroenteritis (AGE) viruses using RT-PCR and sequence analysis.
- Findings revealed high prevalence of rotavirus A and astrovirus, with no decline in enteric viruses during the pandemic, while some strains, like norovirus GII.2, emerged and spread across the regions.
Article Synopsis
- A study in Osaka, Japan tested vaccine-induced neutralizing antibodies against various SARS-CoV-2 variants in serum samples from 32 individuals who received two doses and 10 who received a third dose of vaccine.
- The results showed that the geometric mean titres (GMTs) for key variants after the second dose were significantly lower for the Delta and Omicron BA.1 compared to the D614G strain and Alpha variant.
- After the third dose, GMTs for Omicron BA.1 and BA.2 increased significantly, suggesting that the third dose enhances the antibody response against these variants, providing valuable data for future evaluations of vaccine efficacy against emerging strains.
Article Synopsis
- Respiratory syncytial virus (RSV) in Japan has shown unusual seasonality patterns since 2017, shifting from a typical autumn-winter peak to a summer-autumn pattern, with varied reporting in subsequent years.
- Researchers developed reference thresholds for detecting the start of RSV epidemics using case data, employing a relative operating characteristic curve analysis.
- The established case-per-sentinel (CPS) values for major prefectures in Japan could help in early detection of RSV epidemics and support the potential introduction of monoclonal antibodies for prevention.
Article Synopsis
- This study investigates the shedding of rubella virus (RuV) by analyzing samples from 251 patients with acute rubella infection to better understand how the virus is excreted over time.* -
- Results show that the highest levels of viral RNA were found shortly after the rash appeared, with infectious virus detectable in various samples for up to a few days post-rash onset.* -
- The findings support improved rubella monitoring and diagnosis, suggesting that monitoring viral RNA levels can help identify infectious patients early and prevent the spread of the virus.*
Article Synopsis
- Japan conducted a longitudinal study from 2003 to 2020 on measles-specific antibody levels to assess vaccine effectiveness during different time periods before and after the elimination of measles.
- The study found that while seroprevalence of immunity increased over time, the actual antibody titers decreased, indicating a waning immunity among the population.
- The results suggested that without natural exposure to wild measles strains, the effectiveness of vaccine-induced immunity may diminish, raising concerns about potential future susceptibility to measles in Osaka.
Article Synopsis
- The study examines how longer reporting lags after COVID-19 symptoms can lead to increased transmission and outbreak potential.
- It analyzes epidemiological data from Osaka Prefecture during the early COVID-19 outbreak to identify factors that contribute to delays in reporting cases.
- Findings reveal that younger individuals, those living in high-incidence areas, and people who frequented nightlife districts experienced longer reporting lags, while healthcare workers and those with immunodeficiency reported cases more quickly.
Article Synopsis
- * Recent advancements in mass spectrometry (MS) have shown promise for identifying and typing norovirus, offering higher sensitivity than PCR techniques.
- * The study developed a mass spectrometry-based system that effectively detected over 94% of a norovirus protein, outperforming current PCR methods in distinguishing genetic variations.
Article Synopsis
- The results show an inverse correlation between infectious virus titers in nasopharyngeal swabs and RT-PCR Ct values, indicating that when Ct values exceed 30, the virus is generally undetectable.
- In saliva samples, infectious virus titers were lower, and by 10 days after symptom onset, both sample types typically had Ct values above 30, suggesting minimal risk of transmission after this period.
Full genome-based characterization of G4P[6] rotavirus strains from diarrheic patients in Thailand: Evidence for independent porcine-to-human interspecies transmission events.
Ratana Tacharoenmuang Ratigorn Guntapong Sompong Upachai Phakapun Singchai Saori Fukuda Kazushi Motomura
Virus Genes
August 2021
Article Synopsis
- The evolutionary patterns of G4P[6] rotavirus strains in humans are still unclear, particularly regarding their modes of transmission (animal to human vs. human to human).
- Two specific G4P[6] strains were identified in Thailand from patients with severe diarrhea, showing unique genetic characteristics and similarities to porcine rotavirus strains.
- Genetic and phylogenetic analyses reveal that these strains likely originated from independent transmissions between pigs and humans, which highlights the interactions and exchanges between rotavirus strains across species.
This study investigated the correlation between biochemical markers and viral load among 38 measles cases, including 15 immunologically naive patients and 23 patients with secondary vaccine failure (SVF). We examined four biochemical markers, namely, aspartate aminotransferase, alanine aminotransferase, C-reactive protein, and lactate dehydrogenase (LDH) and their relationship between virus genome copy numbers in peripheral blood mononuclear cells (PBMCs) and throat swabs as well as the concentration of measles-specific IgG. Although viral genome copies in both clinical specimens showed a significant correlation with specific IgG concentration, they had a higher correlation in PBMCs (Pearson's product-moment correlation coefficient, -0.
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- A study in Japan analyzed changes in the seasonal occurrence of respiratory syncytial virus (RSV) infection, which traditionally peaked in autumn and winter.
- The research found that RSV epidemic clusters shifted from September-December (2012-2016) to July-October (2017-2019).
- This earlier trend in RSV infections could impact clinical practices and public health strategies, although the cause of the shift remains uncertain.
Article Synopsis
- - Severe fever with thrombocytopenia syndrome (SFTS) is a tick-borne disease, and this study provides new insights into the SFTSV genome found in Osaka between 2017 and 2018 using next-generation sequencing (NGS).
- - Two genotypes of the virus, C5 and J1, were identified; C5 may have been transmitted from China via birds, while the separate lineage J1 appears localized.
- - The findings indicate distinct transmission patterns for SFTSV in Osaka, suggesting that different genotypes may be spreading separately in the local areas studied.
Article Synopsis
- In Japan, the number of patients with measles vaccination records has increased since the measles virus was eliminated, with a noted lower transmission risk from those with secondary vaccine failure (SVF) compared to primary infections.
- A study analyzed samples from 25 patients infected during a 2016 outbreak to explore both immunological and virological differences between patients with SVF and immunologically naive individuals.
- Results showed that while patients with SVF had significantly lower viral load in blood, indicating a lower transmission risk, viral quantities in throat swabs and urine were comparable to those of naive patients, with the virus isolated only from the naive group.
Article Synopsis
- Recent reports have surfaced regarding the emergence of unusual DS-1-like intergenogroup reassortant rotaviruses with G1/3/8 genotypes across various continents including Africa, Asia, Australia, Europe, and the Americas.
- In Thailand, three novel strains (G9P[8] genotype) were discovered in stool samples from children with diarrhea, and their full genomes were analyzed.
- Phylogenetic analysis revealed that these strains are unique multiple reassortants, indicating their genetic relationship with both human and co-circulating rotavirus strains, marking the first documentation of these specific reassortant strains.
Mammalian orthoreovirus (MRV), also known as reovirus, was discovered in the 1950s and became the first reported segmented double-stranded RNA virus. MRVs have since been found in a variety of animal species, including humans. However, reports on MRV infections are scarce due to the rarity of their symptomatic occurrence.
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