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Primary hepatic mucosa-associated lymphoid tissue (MALT) lymphoma is a relatively rare disease with low malignancy, and its aetiology is unclear. A 65-year-old man presented with abdominal pain. Hepatitis virus examination revealed a previous hepatitis B virus (HBV) infection, and a carbon-13 urea breath test result was positive for the patient. Abdominal contrast-enhanced computed tomography revealed a patch of abnormal density in the right posterior lobe of the liver. The patient underwent VI segment hepatectomy and was pathologically diagnosed with hepatic MALT lymphoma. After the operation, he received quadruple anti-Helicobacter pylori (HP) therapy and refused other treatments. He has been followed up by telephone for 20 months after discharge and is now in a stable condition. In this study, we counted 105 cases of hepatic MALT lymphomas reported in English or Chinese since 1995 and summarised the clinical characteristics and concomitant diseases in this condition. Based on the literature review, we speculated that chronic infectious diseases, especially viral infections (including hepatitis C virus (HCV) and HBV) and HP infection, are associated with the pathogenesis of primary hepatic MALT lymphoma. In addition, autoimmune diseases might also play a role in this condition.
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Infecções por Helicobacter , Helicobacter pylori , Hepatite B , Linfoma de Zona Marginal Tipo Células B , Idoso , Infecções por Helicobacter/tratamento farmacológico , Hepatite B/complicações , Vírus da Hepatite B , Humanos , Linfoma de Zona Marginal Tipo Células B/complicações , Linfoma de Zona Marginal Tipo Células B/tratamento farmacológico , Linfoma de Zona Marginal Tipo Células B/patologia , MasculinoRESUMO
The cellular redox balance plays a significant role in cell fate decisions and in the regulation of responses to various kinds of stress. In this study, we defined a novel concept of the oxidative-redox metabolome, and established a method for the simultaneous quantification of 23 metabolites involved in the oxidative-redox metabolome, covering NAD+ pathway, FAD pathway, GSSG pathway, and ATP pathway by using the AB SCIEX 5500 QTRAP LC/MS/MS system. Corresponding oxidative-redox metabolomics analysis was performed in plasma of humans, hamsters and mice, and hamsters were demonstrated to display a stronger resemblance than mice to humans. The known reductant dithiothreitol (DTT) and oxidant hydrogen peroxide (H2O2) were selected to treat A549 and HeLa cells to validate the current method, showing that DTT moderately increased while H2O2 greatly decreased most analytes. Antibiotic treatment may disturb the oxidative-redox balance in vivo. By comparing the oxidative-redox metabolome in antibiotic-fed hamsters with that of control hamsters, we demonstrated a substantial metabolic disparity between the two, further verifying the applicability and reliability of our method.
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Metaboloma , Espectrometria de Massas em Tandem/métodos , Células A549 , Animais , Cromatografia Líquida de Alta Pressão , Cricetinae , Análise Discriminante , Ditiotreitol/química , Flavina-Adenina Dinucleotídeo/análise , Flavina-Adenina Dinucleotídeo/química , Flavina-Adenina Dinucleotídeo/metabolismo , Células HeLa , Humanos , Peróxido de Hidrogênio/química , Análise dos Mínimos Quadrados , Limite de Detecção , Camundongos , NAD/análise , NAD/química , NAD/metabolismo , OxirreduçãoRESUMO
Avian influenza A(H7N9) virus has caused 5 epidemic waves in China since its emergence in 2013. We investigated the dynamic changes of antibody response to this virus over 1 year postinfection in 25 patients in Suzhou City, Jiangsu Province, China, who had laboratory-confirmed infections during the fifth epidemic wave, October 1, 2016-February 14, 2017. Most survivors had relatively robust antibody responses that decreased but remained detectable at 1 year. Antibody response was variable; several survivors had low or undetectable antibody titers. Hemagglutination inhibition titer was >1:40 for <40% of the survivors. Measured in vitro in infected mice, hemagglutination inhibition titer predicted serum protective ability. Our findings provide a helpful serologic guideline for identifying subclinical infections and for developing effective vaccines and therapeutics to counter H7N9 virus infections.
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Anticorpos Antivirais/imunologia , Subtipo H7N9 do Vírus da Influenza A/imunologia , Influenza Humana/epidemiologia , Influenza Humana/imunologia , Idoso , Animais , Anticorpos Antivirais/sangue , Feminino , História do Século XXI , Hospitalização , Humanos , Subtipo H7N9 do Vírus da Influenza A/classificação , Influenza Humana/história , Influenza Humana/virologia , Masculino , Camundongos , Pessoa de Meia-Idade , Testes Sorológicos , SobreviventesRESUMO
Introduction: Rice blast disease caused by Magnaporthe oryzae has long been the main cause of rice (Oryza sativa L.) yield reduction worldwide. The quinone external inhibitor pyraclostrobin is widely used as a fungicide to effectively control the spread of pathogenic fungi, including M. oryzae. However, M. oryzae can develop resistance through multiple levels of mutation, such as target protein cytb mutation G143A/S, leading to a decrease in the effectiveness of the biocide after a period of application. Therefore, uncovering the possible mutational mechanisms from multiple perspectives will further provide feasible targets for drug development. Methods: In this work, we determined the gene expression changes in M. oryzae in response to pyraclostrobin stress and their relationship with DNA methylation by transcriptome and methylome. Results: The results showed that under pyraclostrobin treatment, endoplasmic reticulum (ER)-associated and ubiquitin-mediated proteolysis were enhanced, suggesting that more aberrant proteins may be generated that need to be cleared. DNA replication and repair processes were inhibited. Glutathione metabolism was enhanced, while lipid metabolism was impaired. The number of alternative splicing events increased. These changes may be related to the elevated methylation levels of cytosine and adenine in gene bodies. Both hypermethylation and hypomethylation of differentially methylated genes (DMGs) mainly occurred in exons and promoters. Some DMGs and differentially expressed genes (DEGs) were annotated to the same pathways by GO and KEGG, including protein processing in the ER, ubiquitin-mediated proteolysis, RNA transport and glutathione metabolism, suggesting that pyraclostrobin may affect gene expression by altering the methylation patterns of cytosine and adenine. Discussion: Our results revealed that 5mC and 6mA in the gene body are associated with gene expression and contribute to adversity adaptation in M. oryzae. This enriched the understanding for potential mechanism of quinone inhibitor resistance, which will facilitate the development of feasible strategies for maintaining the high efficacy of this kind of fungicide.
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BACKGROUND: We estimated symptomatic and asymptomatic influenza infection frequency in community-dwelling unvaccinated pregnant persons to inform risk communication. METHODS: We collected residue sera from multiple antenatal-care blood draws during October 2016-April 2017. We determined influenza infection as seroconversion with ≥ 4-fold rise in antibody titers between any two serum samples by improved hemagglutinin-inhibition assay including ether-treated B antigens. The serology data were linked to the results of nuclei acid testing (rRT-PCR) based on acute respiratory illness (ARI) surveillance. RESULTS: Among all participants, 43 %(602/1384) demonstrated serology and/or rRT-PCR evidenced infection, and 44 %(265/602) of all infections were asymptomatic. ARI-associated rRT-PCR testing identified only 10 %(61/602) of total infections. Only 1 %(5/420) of the B Victoria cases reported ARI and had a rRT-PCR positive result, compared with 33 %(54/165) of the H3N2 cases. Among influenza ARI cases with multiple serum samples, 19 %(11/58) had seroconversion to a different subtype prior to the illness. CONCLUSIONS: The incidence of influenza B infection in unvaccinated pregnant persons is under-estimated substantially. Non-pharmaceutical intervention may have suboptimal effectiveness in preventing influenza B transmission due to the less clinical manifestation compared to influenza A. The findings support maternal influenza vaccination to protect pregnant persons and reduce consequent household transmission.
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Infecções por Herpesviridae , Vacinas contra Influenza , Influenza Humana , Humanos , Feminino , Gravidez , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Vírus da Influenza A Subtipo H3N2 , Vírus da Influenza B , VacinaçãoRESUMO
BACKGROUND: Recent seasonal epidemics of influenza have been caused by human influenza A viruses of the H1N1 and H3N2 subtypes and influenza B viruses. Annual vaccination is recommended to prevent infection; however, how annual influenza vaccination influences vaccine effectiveness is largely unknown. METHODS: To investigate the impact of repeated vaccination on immune and protective effect, we performed a prospective seroepidemiologic study. Participants with or without prior vaccination (2018-2019) were enrolled during the 2019-2020 influenza season. Inactivated quadrivalent influenza vaccine (IIV4) was administered through the intramuscular route, and venous blood samples were collected regularly to test hemagglutination inhibition (HAI) titers. RESULTS: The geometric mean titers and proportion with titers ≥40 against the influenza vaccine components peaked at 30 days post-vaccination. At Day 30, the geometric mean titer and proportion with titers ≥40 in participants who had been previously vaccinated were higher for H3N2 but similar for both B lineages (Victoria and Yamagata) as compared with participants vaccinated for the first time. As for H1N1, the geometric mean titer was lower in repeated vaccinated participants, but the proportion with titers ≥40 was consistent in both groups. CONCLUSIONS: Repeated vaccination provides similar or enhanced protection as compared with single vaccination in first-time vaccinees.
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Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Humanos , Influenza Humana/prevenção & controle , Vírus da Influenza A Subtipo H3N2 , Estudos Prospectivos , Estudos Soroepidemiológicos , Vacinas de Produtos Inativados , Vacinação , Testes de Inibição da Hemaglutinação , Imunidade , Anticorpos AntiviraisRESUMO
The asymmetric unit of the title compound, C(6)H(9)ClN(4), contains four independent mol-ecules (A, B, C and D). Their main difference is the torsion angles, ranging from 1.6â (5) to 5.9â (5)°, between the methyl group and the pyrimidine plane. A pair of inter-molecular N-Hâ¯N hydrogen bonds link mol-ecules A and C into a twisted dimer with a dihedral angle of 32.9â (1)° between the two pyrimidine rings, creating an R(2) (2)(8) motif. In the packing, each two mol-ecules of B, C and D form centrosymmetric dimers through two inter-molecular N-Hâ¯N hydrogen bonds, locally creating R(2) (2)(8) motifs. The dimers of C and D are alternately bridged by A into an infinite zigzag strip, locally creating two different R(2) (2)(8) motifs with dihedral angles of 32.9â (1) and 63.4â (1)° between the pyrimidine rings. Finally, these strips together with the dimers of B associate into a complicated three-dimensional framework.
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Pyrimidines are critical nutrients and key biomolecules in nucleic acid biosynthesis and carbohydrate and lipid metabolism. Here, we proposed the concept of the pyrimidine metabolome, which covers 14 analytes in pyrimidine de novo and salvage synthetic pathways, and established a novel analytical strategy with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to efficiently illustrate pyrimidine transient distribution and dynamic balance. The lower limits of quantification (LLOQs) of all analytes were less than 10 ng/mL. Acceptable inter- and intra-day relative deviation (<15%) was detected, and good stability was obtained under different storage conditions. Metabolomics analysis revealed pyrimidine metabolic diversity in the plasma and brain among species, and a visualization strategy exhibited that pyrimidine biosynthetic metabolism is quite active in brain. Distinct metabolic features were also observed in cells with pyrimidine metabolomic disorders during proliferation and apoptosis. Absolute concentrations of pyrimidine metabolites in different bio-samples offered reference data for future pyrimidine studies.
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Metaboloma , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Metabolômica , PirimidinasRESUMO
BACKGROUND: Data on influenza incidence during pregnancy in China are limited. METHODS: From October 2015 to September 2018, we conducted active surveillance for acute respiratory illness (ARI) among women during pregnancy. Nurses conducted twice weekly phone and text message follow-up upon enrollment until delivery to identify new episodes of ARI. Nasal and throat swabs were collected ≤10 days from illness onset to detect influenza. RESULTS: In total, we enrolled 18 724 pregnant women median aged 28 years old, 37% in first trimester, 48% in second trimester, and 15% in third trimester, with seven self-reported influenza vaccination during pregnancy. In the 18-week epidemic period during October 2015 to September 2016, influenza incidence was 0.7/100 person-months (95% CI: 0.5-0.9). In the cumulative 29-week-long epidemic during October 2016 to September 2017, influenza incidence was 1.0/100 person-months (95% CI: 0.8-1.2). In the 11-week epidemic period during October 2017 to September 2018, influenza incidence was 2.1/100 person-months (95% CI: 1.9-2.4). Influenza incidence was similar by trimester. More than half of the total influenza illnesses had no elevated temperature and cough. Most influenza-associated ARIs were mild, and <5.1% required hospitalization. CONCLUSIONS: Influenza illness in all trimesters of pregnancy was common. These data may help inform decisions regarding the use of influenza vaccine to prevent influenza during pregnancy.
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Vacinas contra Influenza , Influenza Humana , Complicações Infecciosas na Gravidez , Adulto , China/epidemiologia , Feminino , Humanos , Incidência , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Masculino , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/prevenção & controleRESUMO
Nine new coordination polymers, namely, [Mn(2)(L)(H(2)O)(4)].H(2)O (1), [Cd(L)(0.5)(H(2)O)] (2), [Zn(5)(L)(2)(mu(3)-O)(2)(H(2)O)(4)].2H(2)O (3), [Zn(4)(L)(2)(mu(3)-O)(2)][Zn(H(2)O)(5)].2H(2)O (4), [Zn(2)(L)(biim-4)(0.5)(H(2)O)(3)].H(2)O (5), [Cd(2)(L)(bpy)(H(2)O)].2H(2)O.0.5(CH(3)CH(2)OH) (6), [Cu(2)(H(2)L)(2)(bpy)(2)] (7), [Cu(2)(L)(bpy)(H(2)O)] (8), and [Cu(2)(L)(bpy)(1.5)(H(2)O)(2.5)] (9), where H(4)L = 1,2,3,4-benzenetetracarboxylic acid, biim-4 = 1,1'-(1,4-butanediyl)bis(imidazole), and bpy = 4,4'-bipyridine, have been synthesized under hydrothermal conditions. Compound 1 displays a rare trinodal (3,4,7)-connected (4(2).6)(4(5).6)(4(7).6(8).8(6)) topology. 2 possesses an alpha-Po net. 3 is a novel 3D framework based on pentanuclear Zn(II) clusters. By adjustment of the pH values of the reaction mixture of 3 with a Na(2)CO(3) solution, a structurally different compound, 4, was obtained, which exhibits a 3D porous framework with the [Zn(H(2)O)(6)](2+) cations located in the channels. 5 is an unusual example of a trinodal (3,5)-connected network with a Schlafli symbol of (4(2).6)(6(2).8)(4(2).6(2).8(5).10), whereas 6, containing tetranuclear Cd(II) clusters, shows a rare (4,6)-connected (4(4).6(2))(2)(4(4).6(10).8) topology. 7 exhibits a unique polythreading network, while 8 displays a scarce trinodal (3,4,5)-connected self-penetrating network. In comparison with 8, the chiral compound 9 possesses an unprecedented tetranodal (2,4)-connected (7)(7(5).11)(6(2).7(3).8)(2)(6.7(4).10)(2) topology. The effects of the carboxylate ligands, the pH values, the reaction temperatures, the central metals, and the neutral ligands were elucidated. The IR spectra, thermogravimetric analysis, and luminescent properties for the compounds were also investigated.
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To evaluate the quality of Salvia miltiorrhiza Bunge, high-performance liquid chromatography-diode array detector (HPLC/UV-PAD), near infrared (NIR) spectroscopy, and chemometrics were used to discriminate nine components of samples from four different geographical locations. HPLC was performed with a C18 (5 µm, 4.6 mm × 250 mm) column and 0.1% formic acid aqueous solution-acetonitrile with a gradient elution system. Orthogonal partial least squares discriminant analysis was used to identify the amounts of salvianolic acid B. NIR was used to distinguish rapidly S. miltiorrhiza Bunge samples from different geographical locations. In this assay, discriminant analysis was performed, and the accuracy was found to be 100%. The combination of these two methods can be used to quickly and accurately identify S. miltiorrhiza Bunge from different geographical locations.
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Avian influenza A(H5N6) keeps evolving, causing outbreaks in birds and sporadic infections in human. Here, we report a fatal paediatric infection caused by a novel reassortant H5N6 virus. The patient was an obese 9-year-old girl. She initiated with fever and cough, then developed pneumonia, acute respiratory distress syndrome (ARDS) and respiratory failure. Lower respiratory tract aspirates and anal swabs were serially taken till the patient's death. Viral isolation, genome sequencing and phylogenetic analysis were conducted. A novel reassortant H5N6 virus was isolated from the patient. Except the PA gene, all other 7 genes of the virus belonged to H5N6 genotype A (S4-like virus). The PA gene was probably obtained from Eurasian waterfowl influenza viruses. The H5N6 virus was consistently detected from the patient's respiratory samples till the 17th day after symptom onset, but not from anal swabs or urine sample by real-time reverse transcription polymerase chain reaction (RT-PCR). Significantly elevated (32-fold) serum antibodies to H5N6 virus were observed during the patient's course of disease. Aside from the identified novel reassortant H5N6 viral strain, obesity, delayed confirmation of aetiology and specific antiviral treatment, and prolonged virus shedding could have contributed to the poor clinical outcome.
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Since metabolic process differs between humans and mice, studies were performed in hamsters, which are generally considered to be a more appropriate animal model for studies of obesity-related metabolic disorders. The modulation of gut microbiota, bile acids and the farnesoid X receptor (FXR) axis is correlated with obesity-induced insulin resistance and hepatic steatosis in mice. However, the interactions among the gut microbiota, bile acids and FXR in metabolic disorders remained largely unexplored in hamsters. In the current study, hamsters fed a 60% high-fat diet (HFD) were administered vehicle or an antibiotic cocktail by gavage twice a week for four weeks. Antibiotic treatment alleviated HFD-induced glucose intolerance, hepatic steatosis and inflammation accompanied with decreased hepatic lipogenesis and elevated thermogenesis in subcutaneous white adipose tissue (sWAT). In the livers of antibiotic-treated hamsters, cytochrome P450 family 7 subfamily B member 1 (CYP7B1) in the alternative bile acid synthesis pathway was upregulated, contributing to a more hydrophilic bile acid profile with increased tauro-ß-muricholic acid (TßMCA). The intestinal FXR signaling was suppressed but remained unchanged in the liver. This study is of potential translational significance in determining the role of gut microbiota-mediated bile acid metabolism in modulating diet-induced glucose intolerance and hepatic steatosis in the hamster.
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Self-assembly of a tetradentate ligand, N, N'-bi(salicylidene)-2,6-pyridinediamine (H 2L), with Cu(II) or Co(II), affords a dinuclear [Cu 2L 2] complex ( 1) or a trinuclear [Co 3L 3] complex ( 2), which were characterized by the single crystal X-ray diffraction study. The coordination geometry of the Cu (II) centers in 1 is between square planar and tetrahedral, with the ligand adopting a cis-cis conformation to give a centrally symmetric structure, which can be regarded as a mesocate. However, the coordination geometry of Co (II) centers in 2 is distortedly tetrahedral, and the ligand adopts a cis-trans conformation. The whole complex of 2 is of a pseudo- C 3 symmatrical, torus-like structure, which can be regarded as a circular helicate. Both the mesocate and the helicate exhibit expanded supramolecular structures due to elaborate intercomplex pi-stacking interactions. These two complexes were also characterized by element analysis, IR spectra, and TGA. To verify the stability of 2, ESI-MS was carried out on both the crystal and the powdered samples. Variable temperature magnetic susceptibility measurements reveal that both 1 and 2 display antiferromagnetic properties. DFT calculations were carried out on 1 to verify the antiferromagnetic coupling between intracluster metal centers.
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BACKGROUND: The effectiveness of influenza vaccine among nursery school children has not been systematically studied. We conducted a cohort study of children from 13 nursery schools in Suzhou, China, to estimate the effectiveness of influenza vaccine against laboratory-confirmed influenza during 2016-17. METHODS: Children aged 36-72â¯months were chosen from 13 nursery schools from 3 District in Suzhou. The surveillance started 2â¯weeks after vaccination during October 2016-February 2017. Class teachers reported the names of students with ILI (influenza-like illness) to study clinicians on each school day. Further, local physicians collected the student's nasopharyngeal swab or throat swab, either at a study clinic or at the child's home. The swabs were sent to the National Influenza Network Laboratory in Suzhou Center for Disease Control and Prevention for influenza testing by RT-PCR. RESULT: A total of 4614 children were enrolled, of which 15 children (vaccinated: 2; unvaccinated: 13) were lost to follow-up. Of the remaining 4599 children, 558 swabs were collected. Among these swabs, 70 samples tested positive for influenza virus; 17 in the vaccinated group (B Victoria: 2; H3N2: 15) and 53 in the unvaccinated group (B Victoria: 14; A(H1N1)pdm09: 1; H3N2: 38). The overall influenza vaccine effectiveness (VE) during the influenza season of 2016-2017 was 20.6%. The incidence of developing ILI symptoms and healthcare seeking behavior through clinical visits was significantly lower in vaccinated children than in the unvaccinated group. CONCLUSION: Influenza vaccine protection in vaccinated and unvaccinated children showed no statistical difference and the VE percentage varied for different virus subtypes. However, the incidence rate of developing ILI and healthcare seeking behavior was significant lower in the vaccinated group than in the unvaccinated children. Larger studies are required to estimate the VE according to the influenza type, subtype, and lineage during influenza seasons in China in the future.
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Vacinas contra Influenza/imunologia , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Escolas Maternais , Criança , Pré-Escolar , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Incidência , Vacinas contra Influenza/administração & dosagem , Masculino , Nasofaringe/virologia , Orthomyxoviridae/classificação , Orthomyxoviridae/isolamento & purificação , Faringe/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Resultado do TratamentoRESUMO
BACKGROUND: We actively followed a cohort of nursery school children in Suzhou, China to assess the impact of vaccination with trivalent influenza vaccine on the prevention of influenza like illness (ILI). METHODS: We enrolled children aged 36 to 72 months from 13 nursery schools in Suzhou starting two weeks after vaccination during October 2015-February 2016. Every school-day, teachers reported the names of students with ILI to study clinicians, who collected the student's nasopharyngeal swab or throat swab, either at a study clinic or the child's home. Swabs were sent to the Suzhou Center for Disease Control and Prevention's laboratory for influenza testing by RT-PCR. RESULTS: In total, 3278 children were enrolled; 83 (3%) were lost to follow-up, while 3195 (vaccinated: 1492, unvaccinated: 1703) were followed for 24 weeks. During the study, 40 samples tested positive; 17 in the vaccinated (B Victoria: 12; A(H1N1)pdm09: 5) and 23 in the unvaccinated group (B Victoria: 10; B Yamagata: 2; A(H1N1)pdm09: 11). The VE estimates were: 16% overall (95%CI:-58%,56%), 48% (-47%,84%) for influenza A(H1N1)pdm09, 43% (-650%,98%) for influenza B Yamagata, and -37% (-227%,42%) for influenza B Victoria. Data were analyzed by vaccinated and unvaccinated groups based on enrollees' vaccination records. CONCLUSIONS: The VE for A(H1N1)pdm09 was moderate but not significant. Mismatching of B lineage may have compromised trivalent influenza vaccine effectiveness during the 2015-2016 influenza season among nursery school children in Suzhou, China. Additional larger studies are warranted to inform policy related to quadrivalent influenza vaccine licensure in China in the future.
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Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Centers for Disease Control and Prevention, U.S. , Criança , Pré-Escolar , China , Estudos de Coortes , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Masculino , Escolas Maternais , Estações do Ano , Estados Unidos , Vacinação/métodosRESUMO
PURPOSE: Road traffic injuries have become a major public health problem in China. This study aimed to develop statistical models for predicting road traffic deaths and to analyze seasonality of deaths in China. METHODS: A seasonal autoregressive integrated moving average (SARIMA) model was used to fit the data from 2000 to 2011. Akaike Information Criterion, Bayesian Information Criterion, and mean absolute percentage error were used to evaluate the constructed models. Autocorrelation function and partial autocorrelation function of residuals and Ljung-Box test were used to compare the goodness-of-fit between the different models. The SARIMA model was used to forecast monthly road traffic deaths in 2012. RESULTS: The seasonal pattern of road traffic mortality data was statistically significant in China. SARIMA (1, 1, 1) (0, 1, 1)12 model was the best fitting model among various candidate models; the Akaike Information Criterion, Bayesian Information Criterion, and mean absolute percentage error were -483.679, -475.053, and 4.937, respectively. Goodness-of-fit testing showed nonautocorrelations in the residuals of the model (Ljung-Box test, Q = 4.86, P = .993). The fitted deaths using the SARIMA (1, 1, 1) (0, 1, 1)12 model for years 2000 to 2011 closely followed the observed number of road traffic deaths for the same years. The predicted and observed deaths were also very close for 2012. CONCLUSIONS: This study suggests that accurate forecasting of road traffic death incidence is possible using SARIMA model. The SARIMA model applied to historical road traffic deaths data could provide important evidence of burden of road traffic injuries in China.
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Acidentes de Trânsito/estatística & dados numéricos , Morte , Modelos Estatísticos , Estações do Ano , Teorema de Bayes , China/epidemiologia , Humanos , IncidênciaRESUMO
This research aimed to explore the application of autoregressive integrated moving average (ARIMA) model of time series analysis in predicting road traffic injury (RTI) in China and to provide scientific evidence for the prevention and control of RTI. Database was created based on the data collected from monitoring sites in China from 1951 to 2011. The ARIMA model was made. Then it was used to predict RTI in 2012. The ARIMA model of the RTI cases was Yt = e(YËt-1+0.456â¿Yt-1+et) (et stands for random error). The residual error with 16 lags was white noise and the Ljung-Box test statistic for the model was no statistical significance. The model fitted the data well. True value of RTI cases in 2011 was within 95% CI of predicted values obtained from present model. The model was used to predict value of RTI cases in 2012, and the predictor (95%CI) was 207 838 (107 579-401 536). The ARIMA model could fit the trend of RTI in China.