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1.
J Environ Manage ; 366: 121812, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39002463

RESUMO

Improving gas-liquid mass transfer efficiency in aeration systems contributes to energy savings, cost reduction, and enhanced efficiency in wastewater treatment. However, due to the complex nonlinear interactions among bubbles in turbulence, understanding the transport mechanisms of non-uniform bubble clusters in turbulence remains unclear. This study employs a combined approach of experimental research and numerical simulations to investigate the shape, diameter distribution, trajectory, and velocity of bubbles under different aeration port sizes and flow rates. The diameter distribution of bubble clusters exhibits a bimodal distribution. Bubble trajectories during ascent mainly exhibit two types of motion patterns: "Z" shaped and linear. Increasing aeration port size and flow rate both lead to an increase in the maximum bubble diameter. Higher initial flow rates and smaller port sizes induce greater lateral velocity fluctuations in bubbles. The proposed numerical simulation method serves as a reference for simulating the transport of non-uniform bubble clusters.


Assuntos
Simulação por Computador , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Modelos Teóricos
2.
J Am Chem Soc ; 145(9): 5496-5505, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36812021

RESUMO

Achieving transition-metal-catalyzed reactions of diene-ynes/diene-enes and carbon monoxide (CO) to deliver [4 + 2 + 1] cycloadducts, rather than the kinetically favored [2 + 2 + 1] products, is challenging. Here, we report that this can be solved by adding a cyclopropyl (CP) cap to the diene moiety of the original substrates. The resulting CP-capped diene-ynes/diene-enes can react with CO under Rh catalysis to give [4 + 2 + 1] cycloadducts exclusively without forming [2 + 2 + 1] products. This reaction has a broad scope and can be used to synthesize useful 5/7 bicycles with a CP moiety. Of the same importance, the CP moiety in the [4 + 2 + 1] cycloadducts can act as an intermediate group for further transformations so that other challenging bicyclic 5/7 and tricyclic 5/7/5, 5/7/6, and 5/7/7 skeletons, some of which are widely found in natural products, can be accessed. The mechanism of this [4 + 2 + 1] reaction has been investigated by quantum chemical calculations, and the role of the CP group in avoiding the possible side [2 + 2 + 1] reaction has been identified, showing that the [4 + 2 + 1] is controlled by releasing the ring strain in the methylenecyclopropyl (MCP) group (about 7 kcal/mol) in the CP-capped dienes.

3.
Chin J Traumatol ; 26(3): 139-146, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36344366

RESUMO

PURPOSE: High explosives are used to produce blast waves to study their biological effects. The lungs are considered as the critical target organ in blast-effect studies. The degree of lung hemorrhaging is related to both the explosive power and the increased lung weight. We studied the characteristics of the biological effects from an air explosion of a thermobaric bomb in a high-altitude environment and the lethality and lung injury severity of goats in different orientations and distances. METHODS: Goats were placed at 2.5, 3, 4, and 5 m from the explosion center and exposed them to an air blast at an altitude of 4700-meter. A group of them standing oriented to the right side and the other group seated facing the explosion center vertically. The lung injuries were quantified according to the percentage of surface area contused, and using the pathologic severity scale of lung blast injury (PSSLBI) to score the 4 injury categories (slight, moderate, serious and severe) as 1, 2, 3, and 4, respectively. The lung coefficient (lung weight [g]/body weight [kg]) was the indicator of pulmonary edema and was related to lung injury severity. Blast overpressure data were collected using blast test devices placed at matching locations to represent loadings to goats. All statistical analyses were performed using SPSS, version 26.0, statistical software (SPSS, Inc., Chicago, IL, USA). RESULTS: In total, 127 goats were involved in this study. Right-side-standing goats had a significantly higher mortality rate than those seated vertical-facing (p < 0.05). At the 2.5 m distance, the goat mortality was nearly 100%, whereas at 5 m, all the goats survived. Lung injuries of the right-side-standing goats were 1 - 2 grades more serious than those of seated goats at the same distances, the scores of PSSLBI were significantly higher than the seated vertical-facing goats (p < 0.05). The lung coefficient of the right-side-standing goats were significantly higher than those of seated vertical-facing (p < 0.05). Mortality, PSSLBI, and the lung coefficient results indicated that the right-side-standing goats experienced severer injuries than the seated vertical-facing goats, and the injuries were lessened as the distance increased. The blast overpressure was consistent with these results. CONCLUSION: The main killing factors of the thermobaric bomb in the high-altitude environment were blast overpressure, blast wind propulsions and burn. The orientation and distances of the goats significantly affected the blast injury severity. These results may provide a research basis for diagnosing, treating and protecting against injuries from thermobaric explosions.


Assuntos
Traumatismos por Explosões , Lesão Pulmonar , Animais , Lesão Pulmonar/etiologia , Cabras , Explosões , Pulmão/patologia
4.
J Trop Pediatr ; 68(1)2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-35043965

RESUMO

Kawasaki disease (KD) is associated with allergy. As immunoglobulin E (IgE), a key element of allergic reactions, is related with coronary heart disease, we evaluated the serum total IgE levels, and investigated its clinical relevance in 339 children with KD. These patients were classified as high IgE group and normal IgE group according to the reference value of IgE. Serum IgE levels in the high group (279.76 ± 202.54 IU/mL) significantly increased compared with the normal group (5.51 ± 15.79 IU/mL) (p < 0.001). There were also no significant differences in the frequency of major clinical manifestation between the two groups. The number of patients who developed coronary artery lesions (CALs) was significantly higher in the high group (p = 0.004), and the serum levels of IgE were also markedly higher in the KD patients with CALs than in patients without CALs (p = 0.002). High total serum IgE was an independent prognostic for CALs in the multivariate analysis. In conclusion, serum IgE levels may be associated with CALs in children with KD.


Assuntos
Doença da Artéria Coronariana , Síndrome de Linfonodos Mucocutâneos , Criança , Doença da Artéria Coronariana/etiologia , Humanos , Imunoglobulina E , Imunoglobulinas Intravenosas/uso terapêutico , Lactente , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/diagnóstico
5.
J Med Virol ; 93(8): 4846-4855, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33565614

RESUMO

To understand host-pathogen interactions and develop effective prevention and control strategies for human adenovirus (HAdV), it is essential to explore the characteristics of HAdV shedding. Hospitalized children <14 years who had severe HAdV pneumonia were tested for HAdV DNA by quantitative real-time PCR in nasopharyngeal aspirate (NPA). A total of 132 children were enrolled, including 102 patients with HAdV type 7 (HAdV-7) infection and 12 patients with HAdV type 3 (HAdV-3) infection. A total of 1372 qualified NPA samples were collected. There was a significant negative correlation between the viral load of HAdV and the course of the disease (Spearman r = -0.547, p = .000). HAdV-7 load decreased at a rate of 0.089 log10 copies/mL per day (95% CI: -0.096 to -0.081; R 2 = 0.332), and the duration of viral shedding was predicted to be 96.9 days (y = 8.624-0.089x). However, HAdV-3 load decreased more quickly (95% CI: - 0.229 to - 0.143; R 2 = 0.403), and the duration of viral shedding was 51.4 days (y = 9.558-0.186x). The median viral load of the HAdV-7 group at weeks 2 and 3, and more than 3 weeks postinfection was higher than that of the HAdV-3 group. No significant differences in the duration of viral shedding were found in different gender, age (>2 vs. ≤2 years), and with or without underlying diseases groups. Viral shedding in children with severe HAdV pneumonia persisted, among which HAdV-7 lasted longer than 3 months and the viral load decreased slowly than HAdV-3.


Assuntos
Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/fisiologia , Pneumonia Viral/virologia , Eliminação de Partículas Virais , Criança , Pré-Escolar , Feminino , Genótipo , Humanos , Lactente , Cinética , Masculino , Nasofaringe/virologia , Sorogrupo , Carga Viral
6.
Virol J ; 18(1): 238, 2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34847913

RESUMO

PURPOSE: To evaluate viral loads in children with human adenovirus (HAdV) pneumonia at different stages of disease and compare the viral load between upper and lower respiratory tract samples. METHODS: We prospectively enrolled children who required invasive ventilation for HAdV pneumonia. Nasopharyngeal aspirate (NPA) and tracheal aspirate (TA) samples were collected throughout the entire period of invasive ventilation. Viral detection and quantification were performed using quantitative real-time polymerase chain reaction. RESULTS: Ninety-four children were enrolled. The median age of the children was 12.0 months (IQR: 11.0-24.0), and > ninety percent of patients were aged between 6 and 59 months. Seven hundred and nine paired NPA-TA samples were collected. The median viral loads of the NPA and TA samples were 7.31 log10 and 7.50 log10 copies/mL, respectively. Viral loads generally decreased steadily over time. The median viral load after 1, 2, 3, and > 3 weeks of the disease course was 8.65, 7.70, 6.69, and 5.09 log10 copies/mL, respectively, in NPA samples and 8.67, 7.79, 7.08, and 5.53 log10 copies/mL, respectively, in TA samples. Viral load showed a significant negative correlation with time since symptom onset in both NPA samples (Spearman r = - 0.607, P = 0.000) and TA samples (Spearman r = - 0.544, P = 0.000). The predicted duration of HAdV shedding was 60.17 days in the NPA group and 65.81 days in the TA group. Viral loads in NPA and TA from the same subjects correlated well with each other (R2 = 0.694). HAdV loads in NPA and TA were most comparable during the early phase of infection (95% limits of agreement, - 1.36 to 1.30 log10 copies/mL, R2 = 0.746). Variation increased during the late phase of infection (i.e., in follow-up samples), with viral loads remaining significantly higher in TA than NPA. CONCLUSIONS: In children with HAdV pneumonia, viral loads in both NPA and TA steadily decreased during the course of the disease, and the predicted duration of viral shedding was more than 2 months. The HAdV DNA load of NPA is highly correlated with that of TA, especially in the initial phase of infection.


Assuntos
Adenovírus Humanos , Ventilação não Invasiva , Pneumonia , Infecções Respiratórias , Adenovírus Humanos/genética , Criança , Pré-Escolar , Humanos , Lactente , Nasofaringe , Carga Viral
7.
Mediators Inflamm ; 2021: 6650928, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33824623

RESUMO

OBJECTIVES: Interleukin-10 (IL-10) has been suggested as a biomarker of disease activity in patients with adult-onset Still's disease (AOSD). In this study, we evaluated the serum IL-10 levels and investigated its clinical relevance in systemic-onset juvenile idiopathic arthritis (SoJIA). METHODS: IL-10 levels were determined in 21 patients diagnosed with SoJIA and 35 patients with fever diseases which were suspected as SoJIA, and IL-10 levels were compared between SoJIA patients with regard to disease activity, disease courses, and other biomarkers. RESULTS: Patients with SoJIA had significantly higher levels of IL-10 compared to patients with other febrile diseases. The serum levels of IL-10 were significantly higher in active SoJIA compared to inactive and positively correlated with known disease activity markers such as erythrocyte sedimentation rate (ESR), C-reactive protein level (CRP), ferritin (FER), and IL-6 levels. Moreover, the levels of IL-10 at diagnosis were significantly higher in SoJIA patients with a nonmonocyclic pattern than in patients with a monocyclic pattern. Compared to CRP, ESR, FER, and IL-6, IL-10 levels were superior in predicting monocyclic patients from nonmonocyclic patients. CONCLUSION: Compared to other febrile diseases, SoJIA patients have markedly higher levels of IL-10 which may assist with diagnosis. And a clear association of serum IL-10 levels with disease activity and disease courses in SoJIA was found. These results suggest that serum IL-10 might be a reliable clinical marker in SoJIA.


Assuntos
Artrite Juvenil , Interleucina-10/sangue , Biomarcadores/sangue , Sedimentação Sanguínea , Humanos
8.
Nano Lett ; 20(1): 152-157, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31841348

RESUMO

We demonstrate fourth-order quantum beat between sunlight and single photons from a quantum dot. With a fast time-resolved detection system, we observed high-visibility quantum beat between the independent photons of different frequencies from the two astronomically separated light sources. The temporal dynamics of the beat oscillation indicate the coherent behavior of the interfering photons, and the raw visibility of two-photon interference shows violation of the classical limit with a frequency mismatch of three-times the line width.

9.
J Virol ; 93(15)2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31118252

RESUMO

Human noroviruses (huNoVs) recognize histo-blood group antigens (HBGAs) as host susceptibility factors. GII.13 and GII.21 huNoVs form a unique genetic lineage that emerged from mainstream GII NoVs via development of a new, nonconventional glycan binding site (GBS) that binds Lea antigen. This previous finding raised the question of whether the new GII.13/21 GBS really has such a narrow glycan binding spectrum. In this study, we provide solid phenotypic and structural evidence indicating that this new GBS recognizes a group of glycans with a common terminal ß-galactose (ß-Gal). First, we found that P domain proteins of GII.13/21 huNoVs circulating at different times bound three glycans sharing a common terminal ß-Gal, including Lec, lactose, and mucin core 2. Second, we solved the crystal structures of the GII.13 P dimers in complex with Lec and mucin core 2, which showed that ß-Gal is the major binding saccharide. Third, nonfat milk and lactose blocked the GII.13/21 P domain-glycan binding, which may explain the low prevalence of GII.13/21 viruses. Our data provide new insight into the host interactions and epidemiology of huNoVs, which would help in the control and prevention of NoV-associated diseases.IMPORTANCE Evidence from both phenotypic binding assay and structural study support the observed interactions of human noroviruses (huNoVs) with histo-blood group antigens (HBGAs) as receptors or attachment factors, affecting their host susceptibility. GII.13 and GII.21 genotypes form a unique genetic lineage that differs from the mainstream GII huNoVs in their unconventional glycan binding site. Unlike the previous findings that GII.13/21 genotypes recognize only Lea antigen, we found in this study that they can interact with a group of glycans with a common terminal ß-Gal, including Lec, lactose, and mucin core 2. However, this wide glycan binding spectrum in a unique binding mode of the GII.13/21 huNoVs appears not to increase their prevalence, probably due to the existence of decoy glycan receptors in human gastrointestinal tract limiting their infection. Our findings shed light on the host interaction and epidemiology of huNoVs, which would impact the strategy of huNoV control and prevention.


Assuntos
Antígeno CA-19-9/metabolismo , Galactose/metabolismo , Norovirus/fisiologia , Ligação Viral , Antígenos de Grupos Sanguíneos/metabolismo , Genótipo , Humanos , Norovirus/classificação , Norovirus/genética , Ligação Proteica
10.
Opt Express ; 28(13): 18917-18930, 2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32672180

RESUMO

We report a proof-of-principle demonstration of Shor's algorithm with photons generated by an on-demand semiconductor quantum dot single-photon source for the first time. A fully compiled version of Shor's algorithm for factoring 15 has been accomplished with a significantly reduced resource requirement that employs the four-photon cluster state. Genuine multiparticle entanglement properties are confirmed to reveal the quantum character of the algorithm and circuit. The implementation realizes the Shor's algorithm with deterministic photonic qubits, which opens new applications for cluster state beyond one-way quantum computing.

11.
Virol J ; 16(1): 44, 2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30944006

RESUMO

BACKGROUND: Since H7N9 influenza A virus (H7N9) was first reported in 2013, five waves of outbreaks have occurred, posing a huge threat to human health. In preparation for a potential H7N9 epidemic, it is essential to evaluate the efficacy of anti-H7N9 drugs with an appropriate model. METHODS: Well-differentiated pseudostratified human airway epithelium (HAE) cells were grown at the air-liquid interface, and the H7N9 cell tropism and cytopathic effect were detected by immunostaining and hematoxylin-eosin (HE) staining. The H7N9 replication kinetics and anti-H7N9 effect of recombinant human α2b (rhIFN-α2b) and rhIFN-λ1 were compared with different cell lines. The H7N9 viral load and interferon-stimulated gene (ISG) expression were quantified by real-time PCR assays. RESULTS: H7N9 could infect both ciliated and non-ciliated cells within the three-dimensional (3D) HAE cell culture, which reduced the number of cilia and damaged the airways. The H7N9 replication kinetics differed between traditional cells and 3D HAE cells. Interferon had antiviral activity against H7N9 and alleviated epithelial cell lesions; the antiviral activity of rhIFN-α2b was slightly better than that of rhIFN-λ1. In normal cells, rhIFN-α2b induced a greater amount of ISG expression (MX1, OAS1, IFITM3, and ISG15) compared with rhIFN-λ1, but in 3D HAE cells, this trend was reversed. CONCLUSIONS: Both rhIFN-α2b and rhIFN-λ1 had antiviral activity against H7N9, and this protection was related to the induction of ISGs. The 3D cell culture model is suitable for evaluating interferon antiviral activity because it can demonstrate realistic in vivo-like effects.


Assuntos
Subtipo H7N9 do Vírus da Influenza A/efeitos dos fármacos , Interferon alfa-2/farmacologia , Interleucinas/farmacologia , Tropismo Viral , Replicação Viral/efeitos dos fármacos , Antivirais/farmacologia , Linhagem Celular , Citocinas/genética , Células Epiteliais/virologia , Humanos , Subtipo H7N9 do Vírus da Influenza A/imunologia , Interferons , Pulmão/citologia , Proteínas de Membrana/genética , Proteínas de Resistência a Myxovirus/genética , Proteínas de Ligação a RNA/genética , Ubiquitinas/genética
12.
Arch Virol ; 164(9): 2401-2410, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31243554

RESUMO

Rodent populations are known to be reservoirs of viruses with the potential to infect humans. However, a large number of such viruses remain undiscovered. In this study, we investigated the shedding of unknown viruses in long-tailed ground squirrel (Spermophilus undulatus) feces by high-throughput sequencing. A novel and highly divergent virus related to members of the genus Hepacivirus was identified in ground squirrel liver. This virus, tentatively named RHV-GS2015, was found to have a genome organization that is typical of hepaciviruses, including a long open reading frame encoding a polyprotein of 2763 aa. Sequence alignment of RHV-GS2015 with the most closely related hepaciviruses yielded p-distances of the NS3 and NS5B regions of 0.546 and 0.476, respectively, supporting the conclusion that RHV-GS2015 is a member of a new hepacivirus species, which we propose to be named "Hepacivirus P". Phylogenetic analysis of the NS3 and NS5B regions indicated that RHV-GS2015 shares common ancestry with other rodent hepaciviruses (species Hepacivirus E, and species Hepacivirus F), Norway rat hepacivirus 1 (species Hepacivirus G), and Norway rat hepacivirus 2 (species Hepacivirus H). A phylogenetic tree including the seven previously identified rodent hepaciviruses revealed extreme genetic heterogeneity among these viruses. RHV-GS2015 was detected in 7 out of 12 ground squirrel pools and was present in liver, lung, and spleen tissues. Furthermore, livers showed extremely high viral loads of RHV-GS2015, ranging from 2.5 × 106 to 2.0 × 108 copies/g. It is reasonable to assume that this novel virus is hepatotropic, like hepatitis C virus. The discovery of RHV-GS2015 extends our knowledge of the genetic diversity and host range of hepaciviruses, helping to elucidate their origins and evolution.


Assuntos
Hepacivirus/genética , Hepacivirus/isolamento & purificação , Sciuridae/virologia , Animais , China , Variação Genética , Genoma Viral , Hepacivirus/classificação , Hepacivirus/fisiologia , Especificidade de Hospedeiro , Fases de Leitura Aberta , Filogenia , Proteínas Virais/genética
13.
Arch Virol ; 164(9): 2385-2388, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31209596

RESUMO

The discovery and analysis of pathogens carried by non-human primates are important for understanding zoonotic infections in humans. We identified a highly divergent astrovirus (AstV) from fecal matter from a rhesus monkey in China, which has been tentatively named "monkey-feces-associated AstV" (MkAstV). The full-length genome of MkAstV was determined to be 7377 nt in length. It exhibits the standard genomic AstV organization of three open reading frames (ORFs) and is most closely related to duck AstV (28%, 49%, and 35% amino acid sequence identity in ORF1a, ORF1b, and ORF2, respectively). Coincidentally, while this report was being prepared, an astrovirus sequence from Hainan black-spectacled toad became available in the GenBank database, showing 95%, 94% and 92% aa sequence identity in ORF1a, ORF1b and ORF2, respectively, to the corresponding ORFs of MkAstV. Phylogenetic analysis of ORF1a, ORF1b, and ORF2 indicated that MkAstV and the amphibian-related astroviruses formed an independent cluster in the genus Avastrovirus. The host of MkAstV remains unknown. Epidemiological and serological studies of this novel virus should be undertaken in primates, including humans.


Assuntos
Astroviridae/isolamento & purificação , Fezes/virologia , Macaca mulatta/virologia , Sequência de Aminoácidos , Animais , Astroviridae/classificação , Astroviridae/genética , China , Genoma Viral , Fases de Leitura Aberta , Filogenia , Alinhamento de Sequência , Proteínas Virais/genética
14.
BMC Infect Dis ; 19(1): 595, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31288749

RESUMO

BACKGROUND: Noroviruses (NVs) are an important cause of acute gastroenteritis (AGE) worldwide. There are limited data on the prevalence and molecular characterization of NVs in children in Hohhot, China. METHODS: Between January 2012 and December 2017, 1863 stool samples were collected at Maternal and Child Health Hospital in Hohhot. All samples were screened for NVs by real-time reverse transcription polymerase chain reaction (real-time RT-PCR). RESULTS: NVs were detected in 24.15% of these inpatient cases, ranging from 12.78 to 32.92% in different years. NV was detected throughout the year, with a peak in winter. Based on sequence analysis of the partial VP1 gene, the 306 identified NV strains were divided into six genotypes: GII.3 (71.24%), GII.4 (23.53%), and GII.2, GII.5, GII.6, and GII.13 (total 5.23%). Based on further sequence analysis of the RNA-dependent RNA polymerase (RdRp), GII.P12/GII.3, GII.Pe/GII.4, and GII.P4/GII.4 were identified as predominant genotypes, accounting for 92.6% of genotyped strains. The median age of the children with NV infection was 8.0 (range 0-59) months. However, children infected with GII.3 were younger (median 7.0 months) than GII.4-positive patients (median 10.0 months). CONCLUSION: NV contributed greatly to AGE among hospitalized children in Hohhot in China. Continuous surveillance is important for understanding the local prevalence and characterization of NV.


Assuntos
Infecções por Caliciviridae/diagnóstico , Gastroenterite/diagnóstico , Norovirus/genética , Doença Aguda , Infecções por Caliciviridae/epidemiologia , Criança Hospitalizada , Pré-Escolar , China/epidemiologia , Fezes/virologia , Feminino , Gastroenterite/epidemiologia , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Norovirus/classificação , Norovirus/isolamento & purificação , Filogenia , Prevalência , RNA Viral/isolamento & purificação , RNA Viral/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Estações do Ano
15.
Virol J ; 15(1): 161, 2018 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-30340611

RESUMO

BACKGROUND: Rotaviruses (RVs) are a major cause of acute children gastroenteritis. The rotavirus P [10] belongs to P[I] genogroup of group A rotaviruses that mainly infect animals, while the rotavirus P [10] was mainly identified from human infection. The rotavirus P [10] is an unusual genotype and the recognition pattern of cellular receptors remains unclear. METHODS: We expressed and purified the RV P [10] VP8* protein and investigated the saliva and oligosaccharide binding profiles of the protein. A homology model of the P [10] VP8* core protein was built and the superimposition structural analysis of P [10] VP8* protein on P [19] VP8* in complex with mucin core 2 was performed to explore the possible docking structural basis of P [10] VP8* and mucin cores. RESULTS: Our data showed that rotavirus P [10] VP8* protein bound to all ABO secretor and non-secretor saliva. The rotavirus P [10] could bind strongly to mucin core 2 and weakly to mucin core 4. The homology modeling indicated that RV P [10] VP8* binds to mucin core 2 using a potential glycan binding site that is the same to P [19] VP8* belonging to P[II] genogroup. CONCLUSION: Our results suggested an interaction of rotavirus P [10] VP8* protein with mucin core 2 and mucin core 4. These findings offer potential for elucidating the mechanism of RV A host specificity, evolution and epidemiology.


Assuntos
Polissacarídeos/química , Proteínas de Ligação a RNA/química , Infecções por Rotavirus/virologia , Rotavirus/genética , Proteínas não Estruturais Virais/química , Sítios de Ligação , Escherichia coli/genética , Gastroenterite/virologia , Humanos , Simulação de Acoplamento Molecular , Mucinas/química , Mucinas/metabolismo , Polissacarídeos/metabolismo , Ligação Proteica , Proteínas de Ligação a RNA/metabolismo , Saliva/química , Saliva/virologia , Análise de Sequência de Proteína , Proteínas não Estruturais Virais/metabolismo
16.
Arch Virol ; 163(5): 1187-1193, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29387970

RESUMO

To establish an animal model for the newly identified Marmota Himalayana hepatovirus, MHHAV, so as to develop a better understanding of the infection of hepatitis A viruses. Five experimental woodchucks (Marmota monax) were inoculated intravenously with the purified MHHAV from wild woodchuck feces. One animal injected with PBS was defined as a control. Feces and blood were routinely collected. After the animals were subjected to necropsy, different tissues were collected. The presence of viral RNA and negative sense viral RNA was analyzed in all the samples and histopathological and in situ hybridization analysis was performed for the tissues. MHHAV infection caused fever but no severe symptoms or death. Virus was shed in feces beginning at 2 dpi, and MHHAV RNA persisted in feces for ~2 months, with a biphasic increase, and in blood for ~30 days. Viral RNA was detected in all the tissues, with high levels in the liver and spleen. Negative-strand viral RNA was detected only in the liver. Furthermore, the animals showed histological signs of hepatitis at 45 dpi. MHHAV can infect M. monax and is associated with hepatic disease. Therefore, this animal can be used as a model of HAV pathogenesis and to evaluate antiviral and anticancer therapeutics.


Assuntos
Modelos Animais de Doenças , Vírus da Hepatite A/patogenicidade , Hepatite A , Hepatite Viral Animal , Marmota , Animais , Fezes/virologia , Hepatite A/patologia , Hepatite A/fisiopatologia , Hepatite A/virologia , Vírus da Hepatite A/genética , Vírus da Hepatite A/isolamento & purificação , Vírus da Hepatite A/fisiologia , Hepatite Viral Animal/patologia , Hepatite Viral Animal/fisiopatologia , Hepatite Viral Animal/virologia , Fígado/patologia , Fígado/virologia , RNA Viral/isolamento & purificação , Baço/patologia , Baço/virologia
17.
BMC Gastroenterol ; 18(1): 114, 2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-30005618

RESUMO

BACKGROUND: Acute diarrheal illness (ADI) is an important public health problem worldwide. We estimated the morbidity, distribution, and burden of self-reported ADI in China over the last three decades. METHODS: We used the keywords "diarrhea and morbidity" to identify studies published in Chinese by searching CNKI, WANFANG, Chongqing VIP, and SinoMed. Studies published in English were identified using the keywords "diarrhea, morbidity, and China" to search Pubmed/Medline, Embase, and Cochrane Library Data. All articles published before Dec 31, 2014 were included in the search. Data were extracted and the pooled 2-week incidence rate of ADI was calculated using the fixed-effects or random-effects model according to statistical testing for homogeneity. The incidences of each subgroup (organized by age, location, study period) were also calculated. Publication bias was examined using Begg's test. Data manipulation and statistical analyses were undertaken using R-2.15.1 software. RESULTS: We estimated that the pooled 2-week prevalence of ADI in China was 2.04% (95% CI: 1.48-2.79) and that the corresponding incidence rate was 0.53 (95% CI: 0.38-0.73) episodes per person-year. The ADI rate was highest among children aged < 5 years (1.43 episodes per person-year), and it was slightly higher in males than in females (0.58 vs 0.52 episodes per person-year). From 1980 to 2012, there was a significant decrease in the incidence of ADI, from 0.82 to 0.48 episodes per person-year, but the ADI incidence was consistent over the last two decades. Additionally, the incidence of ADI was higher in rural areas and in west China and peaked in the summer months. CONCLUSIONS: The current study indicates that ADI caused a substantial disease burden in China in the last 30 years, especially in rural areas and west China, where sanitation conditions were relatively poor. These findings highlight the importance of further investigation of the specific causes of and effective preventive measures for ADI.


Assuntos
Diarreia/epidemiologia , Adolescente , Distribuição por Idade , Criança , Pré-Escolar , China/epidemiologia , Efeitos Psicossociais da Doença , Feminino , Humanos , Incidência , Masculino , Prevalência , População Rural/estatística & dados numéricos , Estações do Ano , Autorrelato , Distribuição por Sexo , Fatores de Tempo , População Urbana/estatística & dados numéricos
18.
Biomed Environ Sci ; 31(2): 136-145, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29606192

RESUMO

OBJECTIVE: Newly identified human rhinovirus C (HRV-C) and human bocavirus (HBoV) cannot propagate in vitro in traditional cell culture models; thus obtaining knowledge about these viruses and developing related vaccines are difficult. Therefore, it is necessary to develop a novel platform for the propagation of these types of viruses. METHODS: A platform for culturing human airway epithelia in a three-dimensional (3D) pattern using Matrigel as scaffold was developed. The features of 3D culture were identified by immunochemical staining and transmission electron microscopy. Nucleic acid levels of HRV-C and HBoV in 3D cells at designated time points were quantitated by real-time polymerase chain reaction (PCR). Levels of cytokines, whose secretion was induced by the viruses, were measured by ELISA. RESULTS: Properties of bronchial-like tissues, such as the expression of biomarkers CK5, ZO-1, and PCK, and the development of cilium-like protuberances indicative of the human respiration tract, were observed in 3D-cultured human airway epithelial (HAE) cultures, but not in monolayer-cultured cells. Nucleic acid levels of HRV-C and HBoV and levels of virus-induced cytokines were also measured using the 3D culture system. CONCLUSION: Our data provide a preliminary indication that the 3D culture model of primary epithelia using a Matrigel scaffold in vitro can be used to propagate HRV-C and HBoV.


Assuntos
Infecções por Enterovirus/virologia , Enterovirus/crescimento & desenvolvimento , Bocavirus Humano/crescimento & desenvolvimento , Infecções por Parvoviridae/virologia , Cultura Primária de Células/métodos , Mucosa Respiratória/virologia , Colágeno , Combinação de Medicamentos , Enterovirus/isolamento & purificação , Ensaio de Imunoadsorção Enzimática , Células Epiteliais/virologia , Bocavirus Humano/isolamento & purificação , Humanos , Laminina , Proteoglicanas , Reação em Cadeia da Polimerase em Tempo Real , Cultura de Vírus
19.
Entropy (Basel) ; 20(11)2018 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33266593

RESUMO

In this study, a comparative analysis of the statistical index (SI), index of entropy (IOE) and weights of evidence (WOE) models was introduced to landslide susceptibility mapping, and the performance of the three models was validated and systematically compared. As one of the most landslide-prone areas in Shaanxi Province, China, Shangnan County was selected as the study area. Firstly, a series of reports, remote sensing images and geological maps were collected, and field surveys were carried out to prepare a landslide inventory map. A total of 348 landslides were identified in study area, and they were reclassified as a training dataset (70% = 244 landslides) and testing dataset (30% = 104 landslides) by random selection. Thirteen conditioning factors were then employed. Corresponding thematic data layers and landslide susceptibility maps were generated based on ArcGIS software. Finally, the area under the curve (AUC) values were calculated for the training dataset and the testing dataset in order to validate and compare the performance of the three models. For the training dataset, the AUC plots showed that the WOE model had the highest accuracy rate of 76.05%, followed by the SI model (74.67%) and the IOE model (71.12%). In the case of the testing dataset, the prediction accuracy rates for the SI, IOE and WOE models were 73.75%, 63.89%, and 75.10%, respectively. It can be concluded that the WOE model had the best prediction capacity for landslide susceptibility mapping in Shangnan County. The landslide susceptibility map produced by the WOE model had a profound geological and engineering significance in terms of landslide hazard prevention and control in the study area and other similar areas.

20.
J Gen Virol ; 98(4): 612-623, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28100306

RESUMO

With advances in viral surveillance and next-generation sequencing, highly diverse novel astroviruses (AstVs) and different animal hosts had been discovered in recent years. However, the existence of AstVs in marmots had yet to be shown. Here, we identified two highly divergent strains of AstVs (tentatively named Qinghai Himalayanmarmot AstVs, HHMAstV1 and HHMAstV2), by viral metagenomic analysis in liver tissues isolated from wild Marmota himalayana in China. Overall, 12 of 99 (12.1 %) M. himalayana faecal samples were positive for the presence of genetically diverse AstVs, while only HHMAstV1 and HHMAstV2 were identified in 300 liver samples. The complete genomic sequences of HHMAstV1 and HHMAstV2 were 6681 and 6610 nt in length, respectively, with the typical genomic organization of AstVs. Analysis of the complete ORF 2 sequence showed that these novel AstVs are most closely related to the rabbit AstV, mamastrovirus 23 (with 31.0 and 48.0 % shared amino acid identity, respectively). Phylogenetic analysis of the amino acid sequences of ORF1a, ORF1b and ORF2 indicated that HHMAstV1 and HHMAstV2 form two distinct clusters among the mamastroviruses, and may share a common ancestor with the rabbit-specific mamastrovirus 23. These results suggest that HHMAstV1 and HHMAstV2 are two novel species of the genus Mamastrovirus in the Astroviridae. The remarkable diversity of these novel AstVs will contribute to a greater understanding of the evolution and ecology of AstVs, although additional studies will be needed to understand the clinical significance of these novel AstVs in marmots, as well as in humans.


Assuntos
Infecções por Astroviridae/veterinária , Astroviridae/classificação , Astroviridae/isolamento & purificação , Marmota/virologia , Animais , Astroviridae/genética , Infecções por Astroviridae/virologia , China , Análise por Conglomerados , Fezes/virologia , Ordem dos Genes , Genoma Viral , Fígado/virologia , Metagenômica , Filogenia , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Sintenia
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