Publications by authors named "Yen Doan"

Inter-genogroup reassortment of Rotavirus A (RVA) strains has highlighted the spread of unusual RVA strains worldwide. We previously reported the equine-like G3 RVA as the predominant strain in Indonesia in 2015-2016. However, since July 2017, typical human genotypes G1 and G3 have replaced these strains completely.

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Unlabelled: There are four genogroups and 18 genotypes of human sapoviruses (HuSaVs) responsible for acute gastroenteritis. To comprehend their antigenic and virological differences, it is crucial to obtain viral stocks of the different strains. Previously, we utilized the human duodenum-derived cell line HuTu80, and glycocholate, a conjugated bile acid, to replicate and propagate GI.

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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.
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To conduct an epidemiological study of hepatitis E virus (HEV) in Japanese wild boars, we collected 179 serum and 162 fecal specimens from wild boars in eight Japanese prefectures; 39 of the serum samples (21.8%) were positive for anti-HEV IgG antibodies. RT-qPCR revealed HEV RNA in 11 serum samples (6.

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Background: Worldwide, noroviruses are the leading cause of acute gastroenteritis (AGE) in people of all age groups. In India, norovirus rates between 1.4 to 44.

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Rotavirus (RVA) is a leading cause of childhood gastroenteritis. RVA vaccines have reduced the global disease burden; however, the emergence of intergenogroup reassortant strains is a growing concern. During surveillance in Ghana, we observed the emergence of G9P[4] RVA strains in the fourth year after RVA vaccine introduction.

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Rotavirus (RV), norovirus (NoV), sapovirus (SaV), and human astrovirus (HAstV) are the most common viral causes of gastroenteritis in children worldwide. From 2016 to 2021, we conducted a cross-sectional descriptive study to determine the prevalence of these viruses in hospitalized children under five years old in Nam Dinh and Thua Thien Hue provinces in Vietnam during the pilot introduction of the RV vaccine, Rotavin-M1 (POLYVAC, Hanoi, Vietnam). We randomly selected 2317/6718 (34%) acute diarrheal samples from children <5 years of age enrolled at seven sentinel hospitals from December 2016 to May 2021; this period included one year surveillance pre-vaccination from December 2016 to November 2017.

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In-situ chemical oxidation (ISCO) is a commonly used method for the remediation of environmental contaminants in groundwater systems. However, traditional ISCO methods are associated with several limitations, including safety and handling concerns, rebound of groundwater contaminants, and difficulty in reaching all areas of contamination. To overcome these limitations, novel Controlled-Release Biodegradable Polymer (CRBP) pellets containing the oxidant KMnO₄ were designed and tested.

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Norovirus (NoV) is a leading cause of epidemic and sporadic gastroenteritis in people of all ages. Humans are the primary source of NoV and household contact is one of the risk factors for NoV transmission. However, the mechanisms underlying person-to-person NoV transmission are poorly understood.

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Highly positively charged poly(vinyl benzyl trimethylammonium chloride) (PVBMA) was successfully synthesized with approximately 82% of yield. The PVBMA was characterized by the molecular weight (M ) of 343.45 g mol and the molecular weight distribution, (Đ) of 2.

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A Japanese rabbit hepatitis E virus (HEV) strain, JP-59, has been identified in a feral rabbit. When this virus was transmitted to a Japanese white rabbit, it caused persistent HEV infection. The JP-59 strain shares an <87.

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Sapovirus (SaV) infections are a public health problem because they cause acute gastroenteritis in humans of all ages, both sporadically and as outbreaks. However, only a limited amount of SaV sequence information, especially whole-genome sequences for all the SaV genotypes, is publicly available. Therefore, in this study, we determined the full/near-full-length genomic sequences of 138 SaVs from the 2001 to 2015 seasons in 13 prefectures across Japan.

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Genotype 1 hepatitis E virus (HEV-1), unlike other genotypes of HEV, has a unique small open reading frame known as ORF4 whose function is not yet known. ORF4 is located in an out-framed manner in the middle of ORF1, which encodes putative 90 to 158 amino acids depending on the strains. To explore the role of ORF4 in HEV-1 replication and infection, we cloned the complete genome of wild-type HEV-1 downstream of a T7 RNA polymerase promoter, and the following ORF4 mutant constructs were prepared: the first construct had TTG instead of the initiation codon ATG (A2836T), introducing an M→L mutation in ORF4 and a D→V mutation in ORF1.

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Rotavirus A (RVA) is a major viral cause of acute gastroenteritis (AGE) worldwide. G12 RVA strains have emerged globally since 2007. There has been no report of the whole genome sequences of G12 RVAs in Indonesia.

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The adsorption and transformation of tetracyclines (TCs) antibiotics, including oxytetracycline (OTC), chlortetracycline (CTC), and tetracycline (TC), on the sodium dodecyl sulfate (SDS) surfactant-modified α-AlO particles were comprehensively investigated in this study. The TCs adsorption was significantly enhanced by using the modified adsorbents compared with the use of the unmodified adsorbents. The experimental conditions were systematically optimized and found to be pH 4, NaCl 1 mM, the contact time of 180 min, and the adsorbent dosage of 25 mg.

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We devised a reverse genetics system to generate an infectious human sapovirus (HuSaV) GII.3 virus. Capped/uncapped full-length RNAs derived from HuSaV GII.

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Although cell culture systems for hepatitis E virus (HEV) have been established by using cell lines such as PLC/PRF/5 and A549, small-animal models for this virus are limited. Since Mongolia gerbils are susceptible to genotype 1, 3 and 4 HEV (HEV-1, HEV-3 and HEV4), we intraperitoneally inoculated Mongolia gerbils with HEV-5, HEV-7, HEV-8, rabbit HEV or rat HEV in addition to the above three genotypes to investigate the infectivity and to assess whether Mongolia gerbil is an appropriate animal model for HEV infection. The results indicated that (i) HEV-5 and rat HEV were effectively replicated in the Mongolia gerbils in the same manner as HEV-4: large amounts of the viral RNA were detected in the feces and livers, and high titers of the serum anti-HEV IgG antibodies were induced in all animals.

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Objective: We aim to investigate whether the availability of over-the-counter EC varies by neighborhood income level, independent vs chain pharmacies, or urban vs rural pharmacies.

Study Design: We conducted a cross-sectional "mystery shopper" telephone survey in July 2019 to ascertain whether sampled pharmacies stocked EC. Pharmacies located in 12 Pennsylvania counties were randomly sampled after stratification by neighborhood income level.

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Rat hepatitis E virus (rat HEV) was first identified in wild rats and was classified as the species   in the genera , which is genetically different from the genotypes HEV-1 to HEV-8, which are classified as the species  . Although recent reports suggest that rat HEV transmits to humans and causes hepatitis, the infectivity of rat HEV to non-human primates such as cynomolgus and rhesus monkeys remains controversial. To investigate whether rat HEV infects non-human primates, we inoculated one cynomolgus monkey and five rhesus monkeys with a V-105 strain of rat HEV via an intravenous injection.

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Bactrian camel hepatitis E virus (HEV) is a novel HEV belonging to genotype 8 (HEV-8) in the species of the genus in the family . HEV-8 cross-transmits to cynomolgus monkeys and has a potential risk for zoonotic infection. Until now, neither a cell-culture system to grow the virus nor a reverse genetics system to generate the virus has been developed.

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Mammalian orthoreoviruses (MRVs) have been identified in various mammalian species, including humans, bats, and pigs. However, isolation and complete genome sequences of MRVs from wild boars have not yet been reported. In this study, we isolated, sequenced, and analyzed an MRV from a free-living wild boar in Japan using the porcine-sapelovirus-resistant cell line N1380.

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The objective of the present study is to investigate removal of cationic dye, rhodamine B (RhB), in water environment using a high-performance absorbent based on metal oxide nanomaterials toward green chemistry. The adsorption of sodium dodecyl sulfate (SDS) onto synthesized alpha alumina (-AlO) material (0) at different ionic strengths under low pH was studied to fabricate a new adsorbent as SDS-modified -AlO material (1). The RhB removal using 1 was much higher than 0 under the same experimental conditions.

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Noroviruses are recognized as a leading cause of outbreaks and sporadic cases of acute gastroenteritis (AGE) among individuals of all ages worldwide, especially in children <5 years old. We investigated the epidemiology of noroviruses among hospitalized children at two hospitals in East Java, Indonesia. Stool samples were collected from 966 children with AGE during September 2015-July 2019.

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