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1.
Inorg Chem ; 63(19): 8750-8763, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38693869

RESUMEN

Using a quinoline substituted Qsal ligand, Hqsal-5-Brq (Hqsal-5-Brq = N-(5-bromo-8-quinolyl)salicylaldimine), four FeIII complexes, [Fe(qsal-5-Brq)2]A·CH3OH (Y = NO3- (1NO3), BF4- (2BF4), PF6- (3PF6), OTf- (4OTf), were prepared and characterized. Structure analysis revealed that complex 2BF4 contained two species (2BF4(P1̅) and 2BF4(C2/c)). In these compounds except 3PF6, the [Fe(qsal-5-Brq)2]+ cations form 1D chains through π-π interactions and other weak interactions. Adjacent chains are connected to form the 2D "Chain Layer" structures and 3D structures through various supramolecular interactions. For 3PF6, a "Dimer Chain" structure is formed from the loosely connected dimers. Magnetic studies revealed that compounds 1NO3 and 2BF4(P1̅) displayed abrupt hysteretic SCO with the transition temperature T1/2↓ = 235 K, T1/2↑ = 240 K for 1NO3 and T1/2↓ = 230 K, T1/2↑ = 235 K for 2BF4(P1̅), while compounds 3PF6 and 4OTf are in the HS state. Desolvation of the complexes significantly modifies their SCO properties: the desolvated 1NO3 and 2BF4 show a gradual SCO, desolvated 3PF6 undergoes a two-step SCO, and desolvated 4OTf exhibits a hysteretic transition. Overall, this work reported the FeIII-SCO complexes of the quinoline-substituted Hqsal ligand and highlighted the potential of these ligands for the development of interesting FeIII-SCO materials.

2.
Opt Express ; 32(7): 12200-12212, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571050

RESUMEN

As an integral component of the laser interferometry measurement system, the tilt-to-length (TTL) coupling noise inside the telescope stands out as a critical noise factor that requires meticulous consideration. In the TianQin project, the non-geometric TTL-coupled noise inside the telescope should be less than 0.22 pm/Hz1/2. Additionally, the wavefront aberration RMS at the small pupil of the telescope needs to be better than 0.0065 λ. These requirements set for the telescope are exceptionally stringent. To address this challenge, this study aims to relax the wavefront aberration requirements by mitigating non-geometric TTL coupling noise, while ensuring the non-geometric TTL coupling noise remains below 0.22 pm/Hz1/2. By controlling the coupling aberration proportion, the wavefront aberration RMS at the small pupil of the telescope can be relaxed to 0.014 λ. Alternatively, optimizing the Gaussian beam waist radius can relax the wavefront aberration RMS to 0.016 λ. By simultaneously utilizing two optimization methods, the wavefront aberration at the small pupil of the telescope can be reduced to 0.033 λ, resulting in an impressive success rate of 91.15% in meeting the noise requirements.

3.
Infect Med (Beijing) ; 3(1): 100090, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38444745

RESUMEN

Background: Since the first human infection with H9N2 virus was reported in 1998, the number of cases of H9N2 infection has exceeded one hundred by 2021. However, there is no systematic description of the biological characteristics of H9N2 viruses isolated from humans. Methods: Therefore, this study analyzed the pathogenicity in mice of all available H9N2 viruses isolated from human cases in China from 2013 to 2021. Results: Although most of the H9N2 viruses analyzed showed low or no pathogenicity in mice, the leucine to glutamine substitution at residue 226 (L226Q) in the hemagglutinin (HA) protein rapidly emerged during the adaptation of H9N2 viruses, and was responsible for severe infections and even fatalities. HA amino acid 226Q conferred a remarkable competitive advantage on H9N2 viruses in mice relative to viruses containing 226L, increasing their virulence, infectivity, and replication. Conclusion: Thus, our study demonstrates that the adaptive substitution HA L226Q rapidly acquired by H9N2 viruses during the course of infection in mice contributed to their high pathogenicity.

4.
Viruses ; 16(3)2024 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-38543719

RESUMEN

H4 avian influenza viruses (AIVs) have been widely detected in live poultry markets in China. However, the potential public health impact of H4 AIVs remains largely uncertain. Here, we fully analyzed the distribution and phylogenetic relationship of H4 AIVs in China. We obtained 31 isolates of H4 viruses in China during 2009-2022 through surveillance in poultry-associated environments, such as live poultry markets and poultry farms. Genomic sequence analysis together with publicly available data revealed that frequent reassortment and introduction of H4 AIV from wild birds to poultry may have occurred. We identified 62 genotypes among 127 whole genome sequences of H4 viruses in China, indicating that H4 AIVs had great genetic diversity in China. We also investigated molecular markers and found that drug resistance mutations frequently occurred in the M2 protein and a few mutations related to receptor binding and the host signature in H4 AIVs. Our study demonstrates the cross-species transmission potential of H4 AIVs in China and provides some reference significance for its risk assessment.


Asunto(s)
Virus de la Influenza A , Gripe Aviar , Animales , Filogenia , Genoma Viral , Virus de la Influenza A/genética , Evolución Biológica , Aves de Corral , China/epidemiología
5.
Nat Commun ; 15(1): 653, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38253575

RESUMEN

Transition metal dichalcogenides, by virtue of their two-dimensional structures, could provide the largest active surface for reactions with minimal materials consumed, which has long been pursued in the design of ideal catalysts. Nevertheless, their structurally perfect basal planes are typically inert; their surface defects, such as under-coordinated atoms at the surfaces or edges, can instead serve as catalytically active centers. Here we show a reaction probability > 90 % for adsorbed methanol (CH3OH) on under-coordinated Pt sites at surface Te vacancies, produced with Ar+ bombardment, on layered PtTe2 - approximately 60 % of the methanol decompose to surface intermediates CHxO (x = 2, 3) and 35 % to CHx (x = 1, 2), and an ultimate production of gaseous molecular hydrogen, methane, water and formaldehyde. The characteristic reactivity is attributed to both the triangular positioning and varied degrees of oxidation of the under-coordinated Pt at Te vacancies.

6.
Sci Rep ; 13(1): 18424, 2023 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-37891423

RESUMEN

Prostate cancer (PCa) patients with lymph node involvement (LNI) constitute a single-risk group with varied prognoses. Existing studies on this group have focused solely on those who underwent prostatectomy (RP), using statistical models to predict prognosis. This study aimed to develop an easily accessible individual survival prediction tool based on multiple machine learning (ML) algorithms to predict survival probability for PCa patients with LNI. A total of 3280 PCa patients with LNI were identified from the Surveillance, Epidemiology, and End Results (SEER) database, covering the years 2000-2019. The primary endpoint was overall survival (OS). Gradient Boosting Survival Analysis (GBSA), Random Survival Forest (RSF), and Extra Survival Trees (EST) were used to develop prognosis models, which were compared to Cox regression. Discrimination was evaluated using the time-dependent areas under the receiver operating characteristic curve (time-dependent AUC) and the concordance index (c-index). Calibration was assessed using the time-dependent Brier score (time-dependent BS) and the integrated Brier score (IBS). Moreover, the beeswarm summary plot in SHAP (SHapley Additive exPlanations) was used to display the contribution of variables to the results. The 3280 patients were randomly split into a training cohort (n = 2624) and a validation cohort (n = 656). Nine variables including age at diagnosis, race, marital status, clinical T stage, prostate-specific antigen (PSA) level at diagnosis, Gleason Score (GS), number of positive lymph nodes, radical prostatectomy (RP), and radiotherapy (RT) were used to develop models. The mean time-dependent AUC for GBSA, RSF, and EST was 0.782 (95% confidence interval [CI] 0.779-0.783), 0.779 (95% CI 0.776-0.780), and 0.781 (95% CI 0.778-0.782), respectively, which were higher than the Cox regression model of 0.770 (95% CI 0.769-0.773). Additionally, all models demonstrated almost similar calibration, with low IBS. A web-based prediction tool was developed using the best-performing GBSA, which is accessible at https://pengzihexjtu-pca-n1.streamlit.app/ . ML algorithms showed better performance compared with Cox regression and we developed a web-based tool, which may help to guide patient treatment and follow-up.


Asunto(s)
Escisión del Ganglio Linfático , Neoplasias de la Próstata , Masculino , Humanos , Pronóstico , Escisión del Ganglio Linfático/métodos , Ganglios Linfáticos/patología , Neoplasias de la Próstata/patología , Antígeno Prostático Específico
7.
Sensors (Basel) ; 23(12)2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37420726

RESUMEN

This paper proposes the design of a 360° map establishment and real-time simultaneous localization and mapping (SLAM) algorithm based on equirectangular projection. All equirectangular projection images with an aspect ratio of 2:1 are supported for input image types of the proposed system, allowing an unlimited number and arrangement of cameras. Firstly, the proposed system uses dual back-to-back fisheye cameras to capture 360° images, followed by the adoption of the perspective transformation with any yaw degree given to shrink the feature extraction area in order to reduce the computational time, as well as retain the 360° field of view. Secondly, the oriented fast and rotated brief (ORB) feature points extracted from perspective images with a GPU acceleration are used for tracking, mapping, and camera pose estimation in the system. The 360° binary map supports the functions of saving, loading, and online updating to enhance the flexibility, convenience, and stability of the 360° system. The proposed system is also implemented on an nVidia Jetson TX2 embedded platform with 1% accumulated RMS error of 250 m. The average performance of the proposed system achieves 20 frames per second (FPS) in the case with a single-fisheye camera of resolution 1024 × 768, and the system performs panoramic stitching and blending under 1416 × 708 resolution from a dual-fisheye camera at the same time.


Asunto(s)
Aceleración , Algoritmos , Vehículos Autónomos , Registros
8.
China CDC Wkly ; 5(7): 143-151, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-37009519

RESUMEN

Introduction: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has generated 2,431 variants over the course of its global transmission over the past 3 years. To better evaluate the genomic variation of SARS-CoV-2 before and after the optimization of coronavirus disease 2019 (COVID-19) prevention and control strategies, we analyzed the genetic evolution branch composition and genomic variation of SARS-CoV-2 in both domestic and imported cases in China (the data from Hong Kong and Macau Special Administrative Regions and Taiwan, China were not included) from September 26, 2022 to January 29, 2023. Methods: Analysis of the number of genome sequences, sampling time, dynamic changes of evolutionary branches, origin, and clinical typing of SARS-CoV-2 variants submitted by 31 provincial-level administrative divisions (PLADs) and Xinjiang Production and Construction Corps (XPCC) was conducted to assess the accuracy and timeliness of SARS-CoV-2 variant surveillance. Results: From September 26, 2022 to January 29, 2023, 20,013 valid genome sequences of domestic cases were reported in China, with 72 evolutionary branches. Additionally, 1,978 valid genome sequences of imported cases were reported, with 169 evolutionary branches. The prevalence of the Omicron variants of SARS-CoV-2 in both domestic and imported cases was consistent with that of international epidemic variants. Conclusions: This study provides an overview of the prevalence of Omicron variants of SARS-CoV-2 in China. After optimizing COVID-19 prevention and control strategies, no novel Omicron variants of SARS-CoV-2 with altered biological characteristics or public health significance have been identified since December 1, 2022.

9.
Emerg Infect Dis ; 29(6): 1191-1201, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37069608

RESUMEN

The continuous evolution of avian influenza viruses (AIVs) of subtype H3 in China and the emergence of human infection with AIV subtype H3N8 highlight their threat to public health. Through surveillance in poultry-associated environments during 2009-2022, we isolated and sequenced 188 H3 AIVs across China. Performing large-scale sequence analysis with publicly available data, we identified 4 sublineages of H3 AIVs established in domestic ducks in China via multiple introductions from wild birds from Eurasia. Using full-genome analysis, we identified 126 distinct genotypes, of which the H3N2 G23 genotype predominated recently. H3N8 G25 viruses, which spilled over from birds to humans, might have been generated by reassortment between H3N2 G23, wild bird H3N8, and poultry H9N2 before February 2021. Mammal-adapted and drug-resistance substitutions occasionally occurred in H3 AIVs. Ongoing surveillance for H3 AIVs and risk assessment are imperative for potential pandemic preparedness.


Asunto(s)
Subtipo H3N8 del Virus de la Influenza A , Subtipo H9N2 del Virus de la Influenza A , Gripe Aviar , Humanos , Animales , Subtipo H3N8 del Virus de la Influenza A/genética , Subtipo H3N2 del Virus de la Influenza A/genética , Subtipo H9N2 del Virus de la Influenza A/genética , Genoma Viral , Filogenia , Aves , Aves de Corral , China/epidemiología , Mamíferos
10.
Brain Sci ; 13(1)2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36672075

RESUMEN

Background: The number of geriatric traumatic brain injury (TBI) patients is increasing every year due to the population's aging in most of the developed countries. Unfortunately, there is no widely recognized tool for specifically evaluating the prognosis of geriatric TBI patients. We designed this study to compare the prognostic value of different machine learning algorithm-based predictive models for geriatric TBI. Methods: TBI patients aged ≥65 from the Medical Information Mart for Intensive Care-III (MIMIC-III) database were eligible for this study. To develop and validate machine learning algorithm-based prognostic models, included patients were divided into a training set and a testing set, with a ratio of 7:3. The predictive value of different machine learning based models was evaluated by calculating the area under the receiver operating characteristic curve, sensitivity, specificity, accuracy and F score. Results: A total of 1123 geriatric TBI patients were included, with a mortality of 24.8%. Non-survivors had higher age (82.2 vs. 80.7, p = 0.010) and lower Glasgow Coma Scale (14 vs. 7, p < 0.001) than survivors. The rate of mechanical ventilation was significantly higher (67.6% vs. 25.9%, p < 0.001) in non-survivors while the rate of neurosurgical operation did not differ between survivors and non-survivors (24.3% vs. 23.0%, p = 0.735). Among different machine learning algorithms, Adaboost (AUC: 0.799) and Random Forest (AUC: 0.795) performed slightly better than the logistic regression (AUC: 0.792) on predicting mortality in geriatric TBI patients in the testing set. Conclusion: Adaboost, Random Forest and logistic regression all performed well in predicting mortality of geriatric TBI patients. Prognostication tools utilizing these algorithms are helpful for physicians to evaluate the risk of poor outcomes in geriatric TBI patients and adopt personalized therapeutic options for them.

12.
Dalton Trans ; 51(41): 15854-15862, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36190513

RESUMEN

The development of low-cost catalysts for the water oxidation reaction (WOR) is important for solving the bottleneck issues in water splitting and benefits the widespread utilization of renewable energy sources. Herein, four cobalt(II) triazolylpyridine complexes, namely [Co(DTE)2(H2O)2](ClO4)2·CH3COCH3 (1), [Co(DTE)2Cl2]·2CH3OH (2) (DTE = (1-(2-acetoxymethyl)-4-(2-pyridyl)1,2,3-triazole), [Co(DTEL)2(CH3OH)2](ClO4)2 (3), and [Co(DTEL)2Cl2]·H2O (4) (DTEL = (1-(2-hydroxy)-4-(2-pyridyl)1,2,3-triazole), were synthesized and characterized. The crystal structures of 1-3 were determined by X-ray single crystal diffraction analysis. The electrocatalytic water oxidation by 1-4 was studied in 0.1 M NaOAc-HOAc solutions. Complexes 1-4 were single-site molecular catalysts for the WOR under near-neutral conditions. The overpotentials for the WOR were 440 mV and 480 mV. The faradaic efficiencies were 77-92%. The rate constants kcat were 0.21-0.96 s-1. The catalytic activities were affected by the pendant groups of DTE and DTEL. Complexes with DTE (1 and 2) showed better activities than those with DTEL (3 and 4). Moreover, complexes 1-4 adsorbed on indium-doped tin oxide (ITO) and glassy carbon electrode surfaces were active for the WOR. A mechanism was proposed for the WOR catalyzed by 1-4.

13.
Stud Health Technol Inform ; 290: 627-631, 2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-35673092

RESUMEN

Electronic health records (EHRs) at medical institutions provide valuable sources for research in both clinical and biomedical domains. However, before such records can be used for research purposes, protected health information (PHI) mentioned in the unstructured text must be removed. In Taiwan's EHR systems the unstructured EHR texts are usually represented in the mixing of English and Chinese languages, which brings challenges for de-identification. This paper presented the first study, to the best of our knowledge, of the construction of a code-mixed EHR de-identification corpus and the evaluation of different mature entity recognition methods applied for the code-mixed PHI recognition task.


Asunto(s)
Confidencialidad , Registros Electrónicos de Salud , Lenguaje , Procesamiento de Lenguaje Natural , Taiwán
14.
Org Lett ; 24(25): 4694-4698, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35727008

RESUMEN

We demonstrate that dibenzocyclooctendiones (DBCDOs) are efficient chemical reagents for the site-specific labeling of arginine-containing biomolecules. Unlike the commonly used probes, DBCDOs undergo an irreversible ring-contracted rearrangement with the guanidinium group on arginine residues under mild reaction conditions. The regioselective dual-labeled arginine residues were obtained in a one-pot reaction with our tested substrates. The efficiency of DBCDOs reactions and their ease of synthesis make DBCDOs an attractive choice for the site-selective bioconjugation of arginine.


Asunto(s)
Arginina
15.
Emerg Infect Dis ; 28(7): 1332-1344, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35476714

RESUMEN

The recent rise in the frequency of influenza A(H5N6) infections in China has raised serious concerns about whether the risk for human infection has increased. We surveyed epidemiologic, clinical, and genetic data of human infections with A(H5N6) viruses. Severe disease occurred in 93.8% of cases, and the fatality rate was 55.4%. Median patient age was 51 years. Most H5N6 hemagglutinin (HA) genes in human isolates in 2021 originated from subclade 2.3.4.4b; we estimated the time to most recent common ancestor as June 16, 2020. A total of 13 genotypes with HA genes from multiple subclades in clade 2.3.4.4 were identified in human isolates. Of note, 4 new genotypes detected in 2021 were the major causes of increased H5N6 virus infections. Mammalian-adapted mutations were found in HA and internal genes. Although we found no evidence of human-to-human transmission, continuous evolution of H5N6 viruses may increase the risk for human infections.


Asunto(s)
Virus de la Influenza A , Gripe Aviar , Gripe Humana , Animales , China/epidemiología , Humanos , Mamíferos , Persona de Mediana Edad , Filogenia , Virus Reordenados/genética
17.
Zhen Ci Yan Jiu ; 46(8): 635-41, 2021 Aug 25.
Artículo en Chino | MEDLINE | ID: mdl-34472747

RESUMEN

OBJECTIVE: To observe the effect of Sanjiao acupuncture(triple energizer acupuncture)on the small G protein guanosine triphosphate enzyme subfamily protein RhoA/Rho kinase (ROCK) pathway in Alzheimer's disease mice, and explore its effect on learning and memory function and neurosynaptic plasticity. METHODS: Forty SAMP8 senile dementia mice were randomly divided into model, Sanjiao acupuncture (acupuncture), non acupoint acupuncture (non-acupoint) and fasudil groups, with 10 mice in each group, another 10 SAMR normal aging mice were selected as normal aging group. Mice in the acupuncture group were treated with acupuncture intervention on "Danzhong"(CV18), "Zhongwan"(CV13), "Qihai"(BL24) and bilateral "Xuehai"(SP10) and "Zusanli" (ST36). Mice in the non-acupoint group were treated with acupuncture at each of the left and right non-acupoints under the ribs and mice in the fasudil group were intraperitoneally injected with fasudil (25 mg/kg). The mice in each group were given medicine or acupuncture on the second day after grouping for 28 continuously days, once a day. Morris water maze test was used to test the learning and memory ability of mice. HE staining was used to observe the pathological changes of neurons in hippocampus. The number of hippocampal neuron dendritic spine was detected by FD fast Golgi staining kit. The contents of ß-amyloid 42 (Aß42) and phosphorylated tau protein (p-tau) in hippocampus were detected by ELISA. Western blot was used to detect the protein relative expression levels of RhoA, ROCK, F-actin and p-cofilin in hippocampus. RESULTS: Compared with those in the normal aging group, the hippocampal neurons of the model group were disorderly arranged, the number of neuron was reduced, the escape latency, hippocampal Aß42 and p-tau contents, RhoA and ROCK protein expressions increased (P<0.05), the number of crossing the original platform, the number of neuronal dendritic spines, expressions of F-actin and p-cofilin decreased (P<0.05). After the interventions, there was no statistically significant difference in the above indicators in the non-acupoint group relevant to the model group (P>0.05). The acupuncture group and fasudil group improved the hippocampal pathological damage. The escape latency, hippocampal Aß42 and p-tau contents, the expressions of RhoA and ROCK protein decreased (P<0.05), and the number of crossing the original platform, the number of hippocampal neuron dendritic spines, expressions of F-actin and p-cofilin increased (P<0.05) in both of the acupuncture and fasudil groups in contrast to the model and non-acupoint groups. Compared with the acupuncture group, there was no significant difference in the above indicators in the fasudil group (P>0.05). CONCLUSION: Sanjiao acupuncture may inhibit the activation of the RhoA/ROCK pathway, so as to improve the learning and memory function of AD mice, increase the number of hippocampal neuron dendritic spines, and promote synaptic plasticity.


Asunto(s)
Terapia por Acupuntura , Enfermedad de Alzheimer , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/terapia , Animales , Aprendizaje , Ratones , Plasticidad Neuronal , Quinasas Asociadas a rho/genética
18.
Zhongguo Zhong Yao Za Zhi ; 46(13): 3270-3287, 2021 Jul.
Artículo en Chino | MEDLINE | ID: mdl-34396746

RESUMEN

The multi-component pharmacokinetic study of Chinese herbal extracts elaborates the in vivo processes,including absorption,distribution,metabolism,and excretion,of multiple bioactive components,which is of significance in revealing pharmacodynamic material basis of Chinese herbal medicine. In recent years,with the innovation in ideas,and development of techniques and methods on traditional Chinese medicine( TCM) research,the pharmacokinetic studies of Chinese herbal extracts were extensively performed,and notable progress has been made. This paper reviewed the advancement of multi-component pharmacokinetics of Chinese herbal extracts in recent five years from analysis technology of biological sample,the pharmacokinetic characteristics of Chinese herbal medicine with complex system,and the impacts of processing and pathological state on pharmacokinetics of Chinese herbal extracts,aiming to provide a reference for quality control,product development and rational medication of Chinese herbal extracts.


Asunto(s)
Medicamentos Herbarios Chinos , China , Humanos , Medicina Tradicional China , Control de Calidad
19.
Rev Sci Instrum ; 92(4): 044102, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-34243438

RESUMEN

We have developed an experimental system to simultaneously measure surface structure, morphology, composition, chemical state, and chemical activity for samples in gas phase environments. This is accomplished by simultaneously measuring x-ray photoelectron spectroscopy (XPS) and grazing incidence x-ray scattering in gas pressures as high as the multi-Torr regime while also recording mass spectrometry. Scattering patterns reflect near-surface sample structures from the nano-scale to the meso-scale, and the grazing incidence geometry provides tunable depth sensitivity of structural measurements. Scattered x rays are detected across a broad range of angles using a newly designed pivoting-UHV-manipulator for detector positioning. At the same time, XPS and mass spectrometry can be measured, all from the same sample spot and under ambient conditions. To demonstrate the capabilities of this system, we measured the chemical state, composition, and structure of Ag-behenate on a Si(001) wafer in vacuum and in O2 atmosphere at various temperatures. These simultaneous structural, chemical, and gas phase product probes enable detailed insights into the interplay between the structure and chemical state for samples in gas phase environments. The compact size of our pivoting-UHV-manipulator makes it possible to retrofit this technique into existing spectroscopic instruments installed at synchrotron beamlines. Because many synchrotron facilities are planning or undergoing upgrades to diffraction limited storage rings with transversely coherent beams, a newly emerging set of coherent x-ray scattering experiments can greatly benefit from the concepts we present here.

20.
Infect Dis Poverty ; 10(1): 60, 2021 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-33957986

RESUMEN

BACKGROUND: Recurrent infections of animal hosts with avian influenza viruses (AIVs) have posted a persistent threat. It is very important to understand the avian influenza virus distribution and characteristics in environment associated with poultry and wild bird. The aim of this study was to analyze the geographic and seasonal distributions of AIVs in the 31 provinces, municipalities and autonomous region (PMA) of China, compare the AIVs prevalence in different collecting sites and sampling types, analyze the diversity of AIVs subtypes in environment. METHODS: A total of 742 005 environmental samples were collected from environmental samples related to poultry and wild birds in different locations in the mainland of China during 2014-2018. Viral RNA was extracted from the environmental samples. Real-time RT-PCR assays for influenza A, H5, H7 and H9 subtypes were performed on all the samples to identify subtypes of influenza virus. The nucleic acid of influenza A-positive samples were inoculated into embryonated chicken eggs for virus isolation. Whole-genome sequencing was then performed on Illumina platform. SPSS software was used to paired t test for the statistical analysis. ArcGIS was used for drawing map. Graphpad Prism was used to make graph. RESULTS: The nucleic acid positivity rate of influenza A, H5, H7 and H9 subtypes displayed the different characteristics of geographic distribution. The nucleic acid positivity rates of influenza A were particularly high (25.96%-45.51%) in eleven provinces covered the Central, Eastern, Southern, Southwest and Northwest of China. The nucleic acid positivity rates of H5 were significantly high (11.42%-13.79%) in two provinces and one municipality covered the Southwest and Central of China. The nucleic acid positivity rates of H7 were up to 4% in five provinces covered the Eastern and Central of China. The nucleic acid positivity rates of H9 were higher (13.07%-2.07%) in eleven PMA covered the Southern, Eastern, Central, Southwest and Northwest of China. The nucleic acid positivity rate of influenza A, H5, H7 and H9 showed the same seasonality. The highest nucleic acid positivity rates of influenza A, H5, H7, H9 subtypes were detected in December and January and lowest from May to September. Significant higher nucleic acid positivity rate of influenza A, H5, H7 and H9 were detected in samples collected from live poultry markets (LPM) (30.42%, 5.59%, 4.26%, 17.78%) and poultry slaughterhouses (22.96%, 4.2%, 2.08%, 12.63%). Environmental samples that were collected from sewage and chopping boards had significantly higher nucleic acid positivity rates for influenza A (36.58% and 33.1%), H5 (10.22% and 7.29%), H7(4.24% and 5.69%)and H9(21.62% and 18.75%). Multiple subtypes of AIVs including nine hemagglutinin (HA) and seven neuraminidase (NA) subtypes were isolated form the environmental samples. The H5, H7, and H9 subtypes accounted for the majority of AIVs in environment. CONCLUSIONS: In this study, we found the avian influenza viruses characteristics of geographic distribution, seasonality, location, samples types, proved that multiple subtypes of AIVs continuously coexisted in the environment associated with poultry and wild bird, highlighted the need for environmental surveillance in China.


Asunto(s)
Gripe Aviar , Orthomyxoviridae , Animales , Pollos , China/epidemiología , Monitoreo del Ambiente , Gripe Aviar/epidemiología
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