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1.
Nat Commun ; 15(1): 886, 2024 Jan 30.
Article in English | MEDLINE | ID: mdl-38286824

ABSTRACT

Turbulent energy dissipation is a fundamental process in plasma physics that has not been settled. It is generally believed that the turbulent energy is dissipated at electron scales leading to electron energization in magnetized plasmas. Here, we propose a micro accelerator which could transform electrons from isotropic distribution to trapped, and then to stream (Strahl) distribution. From the MMS observations of an electron-scale coherent structure in the dayside magnetosheath, we identify an electron flux enhancement region in this structure collocated with an increase of magnetic field strength, which is also closely associated with a non-zero parallel electric field. We propose a trapping model considering a field-aligned electric potential together with the mirror force. The results are consistent with the observed electron fluxes from ~50 eV to ~200 eV. It further demonstrates that bidirectional electron jets can be formed by the hourglass-like magnetic configuration of the structure.

2.
IEEE Trans Neural Netw Learn Syst ; 34(9): 5614-5628, 2023 Sep.
Article in English | MEDLINE | ID: mdl-34855602

ABSTRACT

Along with the advancement of manipulation technologies, image modification is becoming increasingly convenient and imperceptible. To tackle the challenging image tampering detection problem, this article presents an attentional cross-domain deep architecture, which can be trained end-to-end. This architecture is composed of three convolutional neural network (CNN) streams to extract three types of features, including visual perception, resampling, and local inconsistency features, from spatial and frequency domains. The multitype and cross-domain features are then combined to formulate hybrid features to distinguish manipulated regions from nonmanipulated parts. Compared with other deep architectures, the proposed one spans a more complementary and discriminative feature space by integrating richer types of features from different domains in a unified end-to-end trainable framework and thus can better capture artifacts caused by different types of manipulations. In addition, we design and train a module called tampering discriminative attention network (TDA-Net) to highlight suspicious parts. These part-level representations are then integrated with the global ones to further enhance the discriminating capability of the hybrid features. To adequately train the proposed architecture, we synthesize a large dataset containing various types of manipulations based on DRESDEN and COCO. Experiments on four public datasets demonstrate that the proposed model can localize various manipulations and achieve the state-of-the-art performance. We also conduct ablation studies to verify the effectiveness of each stream and the TDA-Net module.

3.
J Geophys Res Space Phys ; 127(4): e2022JA030280, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35866073

ABSTRACT

At Mercury, several processes can release ions and neutrals out of the planet's surface. Here we present enhancements of planetary ions (Na+-group ions) in Mercury's northern magnetospheric cusp during flux transfer event (FTE) "showers." FTE showers are intervals of intense dayside magnetopause reconnection, during which FTEs are observed in quick succession, that is, only separated by a few seconds. This study identifies 1953 FTE shower intervals and 1795 Non-FTE shower intervals. During the shower intervals, this study shows that the FTEs form a solar wind entry layer equatorward of the northern magnetospheric cusp. In this entry layer, solar wind ions are accelerated and move downward (i.e., planetward) toward the cusp, which sputter upward-moving planetary ions with a particle flux of 1 × 1011 m-2 s-1 within 1 min. The precipitation rate is estimated to increase by an order of magnitude during FTE showers, to 2 × 1025 s-1, and the neutral density of the exosphere could vary by >10% in response to this FTE-driven sputtering. Such rapid large-scale variations driven by dayside reconnection may explain the minute-to-minute changes in Mercury's exosphere, especially on the high latitudes, observed by ground-based telescopes on Earth. Our MESSENGER in situ observation of enhanced planetary ions in the entry layer likely corresponds to an escape channel for Mercury's planetary ions. Comprehensive, future multipoint measurements made by BepiColombo will greatly enhance our understanding of the processes contributing to Mercury's dynamic exosphere and magnetosphere.

4.
Bioresour Technol ; 358: 127383, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35644455

ABSTRACT

Biological valorization of lignin to bioplastics is a promising route to improve biorefinery efficiency and address environmental challenges. A two-stage screening procedure had been designed to successfully identify four ligninolytic bacteria from soil samples. The isolated bacteria displayed substrate preference of guaiacyl- and hydroxyphenyl-based aromatics, but they effectively synthesized polyhydroxyalkanoates (PHAs). B. cepacia B1-2 and P. putida KT3-1 accumulated 27.3% and 20.9% PHA in cells and achieved a titer of 280.9 and 204.1 mg/L, respectively, from p-hydroxybenzoic acid. The isolated bacteria exhibited good ligninolytic performance indicated by the degradation of ß-O-4 linkage and small molecules. B. cepacia B1-2 grew well on actual lignin substrate and yielded a PHA titer of 87.2 mg/L. With the design of fed-batch mode, B. cepacia B1-2 produced the highest PHA titer of 1420 mg/L from lignin-derived aromatics. Overall, isolated ligninolytic bacteria show good PHA accumulation capacity, which are the promising host strains for lignin valorization.


Subject(s)
Lignin , Polyhydroxyalkanoates , Bacteria/metabolism , Lignin/chemistry , Polyhydroxyalkanoates/metabolism
5.
Front Microbiol ; 13: 923664, 2022.
Article in English | MEDLINE | ID: mdl-35707171

ABSTRACT

As the most abundant natural aromatic resource, lignin valorization will contribute to a feasible biobased economy. Recently, biological lignin valorization has been advocated since ligninolytic microbes possess proficient funneling pathways of lignin to valuable products. In the present study, the potential to convert an actual lignin stream into polyhydroxyalkanoates (PHAs) had been evaluated using ligninolytic genome-reduced Pseudomonas putida. The results showed that the genome-reduced P. putida can grow well on an actual lignin stream to successfully yield a high PHA content and titer. The designed fermentation strategy almost eliminated the substrate effects of lignin on PHA accumulation. Employing a fed-batch strategy produced the comparable PHA contents and titers of 0.35 g/g dried cells and 1.4 g/L, respectively. The molecular mechanism analysis unveiled that P. putida consumed more small and hydrophilic lignin molecules to stimulate cell growth and PHA accumulation. Overall, the genome-reduced P. putida exhibited a superior capacity of lignin bioconversion and promote PHA accumulation, providing a promising route for sustainable lignin valorization.

6.
PLoS Negl Trop Dis ; 16(1): e0010048, 2022 01.
Article in English | MEDLINE | ID: mdl-34986169

ABSTRACT

BACKGROUND: The first community transmission of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta variant of concern (VOC) in Guangzhou, China occurred between May and June 2021. Herein, we describe the epidemiological characteristics of this outbreak and evaluate the implemented containment measures against this outbreak. METHODOLOGY/PRINCIPAL FINDINGS: Guangzhou Center for Disease Control and Prevention provided the data on SARS-CoV-2 infections reported between 21 May and 24 June 2021. We estimated the incubation period distribution by fitting a gamma distribution to the data, while the serial interval distribution was estimated by fitting a normal distribution. The instantaneous effective reproductive number (Rt) was estimated to reflect the transmissibility of SARS-CoV-2. Clinical severity was compared for cases with different vaccination statuses using an ordinal regression model after controlling for age. Of the reported local cases, 7/153 (4.6%) were asymptomatic. The median incubation period was 6.02 (95% confidence interval [CI]: 5.42-6.71) days and the means of serial intervals decreased from 5.19 (95% CI: 4.29-6.11) to 3.78 (95% CI: 2.74-4.81) days. The incubation period increased with age (P<0.001). A hierarchical prevention and control strategy against COVID-19 was implemented in Guangzhou, with Rt decreasing from 6.83 (95% credible interval [CrI]: 3.98-10.44) for the 7-day time window ending on 27 May 2021 to below 1 for the time window ending on 8 June and thereafter. Individuals with partial or full vaccination schedules with BBIBP-CorV or CoronaVac accounted for 15.3% of the COVID-19 cases. Clinical symptoms were milder in partially or fully vaccinated cases than in unvaccinated cases (odds ratio [OR] = 0.26 [95% CI: 0.07-0.94]). CONCLUSIONS/SIGNIFICANCE: The hierarchical prevention and control strategy against COVID-19 in Guangzhou was timely and effective. Authorised inactivated vaccines are likely to contribute to reducing the probability of developing severe disease. Our findings have important implications for the containment of COVID-19.


Subject(s)
COVID-19 Vaccines/therapeutic use , COVID-19/epidemiology , COVID-19/prevention & control , Communicable Disease Control/methods , SARS-CoV-2/isolation & purification , Adult , Aged , Basic Reproduction Number , COVID-19/transmission , China/epidemiology , Female , Humans , Male , Middle Aged , Primary Prevention/methods , Severity of Illness Index , Vaccination/statistics & numerical data , Young Adult
7.
Tumori ; 107(3): 216-225, 2021 Jun.
Article in English | MEDLINE | ID: mdl-32762285

ABSTRACT

PURPOSE: To retrospectively explore the survival predictors and treatment efficacy of advanced pneumonic-type lung adenocarcinoma (P-ADC). METHODS: Retrospective analysis of clinical data and survival follow-up was undertaken on 41 patients with advanced P-ADC from January 1, 2009, to April 30, 2019. Analysis on tumor biomarkers such as carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), and the cytokeratin-19-fragment (Cyfra21-1) were undertaken. The patients in this study were divided into three groups based on usage of tyrosine kinase inhibitor (TKI): TKI therapy group (including combination with chemotherapy), non-TKI therapy group (chemotherapy alone), and palliative care group. RESULTS: More than half of the patients had higher levels of tumor biomarkers and the incidence of NSE was highest (81.8%), followed by CEA (74.4%) and Cyfra21-1 (74.1%). All patients had abnormal findings on chest computed tomography and with adenocarcinoma pathology. The overall survival (OS) time was 10.4 months in TKI group, 8.8 months in the non-TKI group, and 2.1 months in the palliative care group. Patients with higher level of serum Cyfra21-1 had insignificantly shorter survival time compared to those with normal Cyfra21-1 (p = 0.067). TKI therapy and non-TKI therapy provided a better prognosis prediction compared to palliative care. TKI therapy improved prognosis compared to non-TKI therapy. The comprehensive based TKI therapy provided improved OS vs the non-TKI therapy. CONCLUSION: TKI-based therapy could improve the prognosis and OS for advanced P-ADC. This study recommends the analysis of EGFR mutations for all patients with advanced P-ADC.


Subject(s)
Adenocarcinoma of Lung/drug therapy , Adenocarcinoma of Lung/mortality , Lung Neoplasms/drug therapy , Lung Neoplasms/mortality , Protein Kinase Inhibitors/therapeutic use , Adenocarcinoma of Lung/metabolism , Aged , Antigens, Neoplasm/metabolism , Biomarkers, Tumor/metabolism , Female , Humans , Keratin-19/metabolism , Lung Neoplasms/pathology , Male , Middle Aged , Prognosis , Retrospective Studies , Treatment Outcome
8.
Nat Commun ; 11(1): 5616, 2020 Nov 05.
Article in English | MEDLINE | ID: mdl-33154395

ABSTRACT

NASA's Magnetospheric Multi-Scale (MMS) mission is designed to explore the proton- and electron-gyroscale kinetics of plasma turbulence where the bulk of particle acceleration and heating takes place. Understanding the nature of cross-scale structures ubiquitous as magnetic cavities is important to assess the energy partition, cascade and conversion in the plasma universe. Here, we present theoretical insight into magnetic cavities by deriving a self-consistent, kinetic theory of these coherent structures. By taking advantage of the multipoint measurements from the MMS constellation, we demonstrate that our kinetic model can utilize magnetic cavity observations by one MMS spacecraft to predict measurements from a second/third spacecraft. The methodology of "observe and predict" validates the theory we have derived, and confirms that nested magnetic cavities are self-organized plasma structures supported by trapped proton and electron populations in analogous to the classical theta-pinches in laboratory plasmas.

9.
Mar Drugs ; 18(8)2020 Aug 12.
Article in English | MEDLINE | ID: mdl-32806493

ABSTRACT

The ongoing development of new production methods may lead to the commercialization of N-acetyl chitooligosaccharides (NACOS), such as chitosan oligosaccharides (COS). The bioactivity of NACOS, although not well detailed, differs from that of COS, as they have more acetyl groups than COS. We used two enzymatically produced NACOS with different molecular compositions and six NACOS (NACOS1-6) with a single degree of polymerization to verify their immunomodulatory effects on the RAW264.7 macrophage cell line. We aimed to identify any differences between COS and various NACOS with a single degree of polymerization. The results showed that NACOS had similar immune enhancement effects on RAW264.7 cells as COS, including the generation of reactive oxygen species (ROS), phagocytotic activity, and the production of pro-inflammation cytokines (IL-1ß, IL-6, and TNF-α). However, unlike COS and lipopolysaccharide (LPS), NACOS1 and NACOS6 significantly inhibited nitric oxide (NO) production. Besides their immune enhancement effects, NACOS also significantly inhibited the LPS-induced RAW264.7 inflammatory response with some differences between various polymerization degrees. We confirmed that the NF-κB pathway is associated with the immunomodulatory effects of NACOS on RAW264.7 cells. This study could inform the application of NACOS with varying different degrees of polymerization in human health.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Immunologic Factors/pharmacology , Macrophages/drug effects , Oligosaccharides/pharmacology , Animals , Interleukin-1beta/genetics , Interleukin-1beta/metabolism , Interleukin-6/genetics , Interleukin-6/metabolism , Macrophages/immunology , Macrophages/metabolism , Mice , NADPH Oxidase 2/genetics , NADPH Oxidase 2/metabolism , NF-kappa B/metabolism , Nitric Oxide Synthase Type II/genetics , Nitric Oxide Synthase Type II/metabolism , Phagocytosis/drug effects , RAW 264.7 Cells , Reactive Oxygen Species/metabolism , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism
10.
Proc Natl Acad Sci U S A ; 117(28): 16193-16198, 2020 07 14.
Article in English | MEDLINE | ID: mdl-32601186

ABSTRACT

A distinct class of aurora, called transpolar auroral arc (TPA) (in some cases called "theta" aurora), appears in the extremely high-latitude ionosphere of the Earth when interplanetary magnetic field (IMF) is northward. The formation and evolution of TPA offers clues about processes transferring energy and momentum from the solar wind to the magnetosphere and ionosphere during a northward IMF. However, their formation mechanisms remain poorly understood and controversial. We report a mechanism identified from multiple-instrument observations of unusually bright, multiple TPAs and simulations from a high-resolution three-dimensional (3D) global MagnetoHydroDynamics (MHD) model. The observations and simulations show an excellent agreement and reveal that these multiple TPAs are generated by precipitating energetic magnetospheric electrons within field-aligned current (FAC) sheets. These FAC sheets are generated by multiple-flow shear sheets in both the magnetospheric boundary produced by Kelvin-Helmholtz instability between supersonic solar wind flow and magnetosphere plasma, and the plasma sheet generated by the interactions between the enhanced earthward plasma flows from the distant tail (less than -100 RE) and the enhanced tailward flows from the near tail (about -20 RE). The study offers insight into the complex solar wind-magnetosphere-ionosphere coupling processes under a northward IMF condition, and it challenges existing paradigms of the dynamics of the Earth's magnetosphere.

11.
Nat Commun ; 11(1): 1668, 2020 Apr 03.
Article in English | MEDLINE | ID: mdl-32245960

ABSTRACT

Energy circulation in geospace lies at the heart of space weather research. In the inner magnetosphere, the steep plasmapause boundary separates the cold dense plasmasphere, which corotates with the planet, from the hot ring current/plasma sheet outside. Theoretical studies suggested that plasmapause surface waves related to the sharp inhomogeneity exist and act as a source of geomagnetic pulsations, but direct evidence of the waves and their role in magnetospheric dynamics have not yet been detected. Here, we show direct observations of a plasmapause surface wave and its impacts during a geomagnetic storm using multi-satellite and ground-based measurements. The wave oscillates the plasmapause in the afternoon-dusk sector, triggers sawtooth auroral displays, and drives outward-propagating ultra-low frequency waves. We also show that the surface-wave-driven sawtooth auroras occurred in more than 90% of geomagnetic storms during 2014-2018, indicating that they are a systematic and crucial process in driving space energy dissipation.

12.
Sci Total Environ ; 663: 227-235, 2019 May 01.
Article in English | MEDLINE | ID: mdl-30711589

ABSTRACT

OBJECTIVE: To explore the relationship between meteorological factors and scarlet fever incidence from 2006 to 2017 in Guangzhou, the largest subtropical city of Southern China, and assist public health prevention and control measures. METHODS: Data for weekly scarlet fever incidence and meteorological variables from 2006 to 2017 in Guangzhou were collected from the National Notifiable Disease Report System (NNDRS) and the Guangzhou Meteorological Bureau (GZMB). Distributed lag nonlinear models (DLNMs) were conducted to estimate the effect of meteorological factors on weekly scarlet fever incidence in Guangzhou. RESULTS: We observed nonlinear effects of temperature, relative humidity, and wind velocity. The risk was the highest when the weekly mean temperature was 31 °C during lag week 14, yielding a relative risk (RR) of 1.48 (95% CI: 1.01-2.17). When relative humidity was 43.5% during lag week 0, the RR was 1.49 (95% CI: 1.04-2.12); the highest RR (1.55, 95% CI: 1.20-1.99) was reached when relative humidity was 93.5% during lag week 20. When wind velocity was 4.4 m/s during lag week 13, the RR was highest at 3.41 (95% CI: 1.57-7.44). Positive correlations were observed among weekly temperature ranges and atmospheric pressure with scarlet fever incidence, while a negative correlation was detected with aggregate rainfall. The cumulative extreme effect of meteorological variables on scarlet fever incidence was statistically significant, except for the high effect of wind velocity. CONCLUSION: Weekly mean temperature, relative humidity, and wind velocity had double-trough effects on scarlet fever incidence; high weekly temperature range, high atmospheric pressure, and low aggregate rainfall were risk factors for scarlet fever morbidity. Our findings provided preliminary, but fundamental, information that may be useful for a better understanding of epidemic trends of scarlet fever and for developing an early warning system. Laboratory surveillance for scarlet fever should be strengthened in the future.


Subject(s)
Humidity , Scarlet Fever/epidemiology , Wind , China/epidemiology , Incidence , Meteorological Concepts , Nonlinear Dynamics , Scarlet Fever/microbiology , Temperature , Urban Population/statistics & numerical data
13.
Asia Pac J Ophthalmol (Phila) ; 5(2): 127-32, 2016.
Article in English | MEDLINE | ID: mdl-26765037

ABSTRACT

PURPOSE: To compare the 24-hour ocular perfusion pressure (OPP) among patients with primary open angle glaucoma (POAG) and those with suspected POAG identified in a population-based study in China. METHODS: Forty-seven patients with POAG and 35 with suspected POAG attended the 24-hour OPP study. Intraocular pressure (IOP) and blood pressure (BP) were measured at 2, 6, and 10 AM and 2, 6, and 10 PM. Subjects were not taking any medications to lower IOP, which was measured with Goldmann applanation in an upright sitting position. Blood pressure was measured in a supine position using a digital automatic BP monitor (OMRON, model HEM-907). Mean arterial pressure was calculated as diastolic BP + 1[Fraction Slash]3 × (systolic BP - diastolic BP). Mean OPP (MOPP) was defined as 2[Fraction Slash]3 × mean arterial pressure - IOP, systolic OPP (SOPP) was defined as 2[Fraction Slash]3 × systolic BP - IOP, and diastolic OPP (DOPP) was defined as 2[Fraction Slash]3 × diastolic BP - IOP. RESULTS: After adjustment for age, sex, and IOP, the maximum, mean, and minimum SOPP, DOPP, and MOPP were statistically significantly lower in subjects with POAG than in those with suspected POAG (P < 0.05). The minimum MOPP, SOPP, and DOPP occurred from 10 AM to 2 PM in approximately 60% of eyes with POAG and between 20% and 30% of minimum MOPP, SOPP, and DOPP occurred around 10 PM. CONCLUSIONS: Systolic OPP, DOPP, and MOPP were consistently lower in eyes with POAG than in those with suspected POAG, providing further evidence that OPP plays a role in the development of glaucoma.


Subject(s)
Arterial Pressure/physiology , Blood Pressure/physiology , Glaucoma, Open-Angle/physiopathology , Intraocular Pressure/physiology , Aged , Antihypertensive Agents/pharmacology , China , Circadian Rhythm/physiology , Female , Humans , Male , Middle Aged , Tonometry, Ocular
14.
Zhonghua Liu Xing Bing Xue Za Zhi ; 34(9): 900-5, 2013 Sep.
Article in Chinese | MEDLINE | ID: mdl-24331967

ABSTRACT

OBJECTIVE: To analyze the results of avian influenza surveillance program in Guangzhou from 2006 to 2012 and to evaluate the risk of infections with H5, H7 and H9 subtypes avian influenza viruses. METHODS: Avian influenza surveillance system in Guangzhou consisted five components:serum surveillance on occupational population, environmental specimen surveillance of avian influenza virus, avian flu emergency surveillance, influenza viruses surveillance on ILI patient and surveillance on pneumonia of unknown causes. Hemagglutination inhibition test was conducted to detect the antibodies against H5, H7 and H9 while RT-PCR was used to test the nucleic acid of H5, H7 and H9 viruses. RESULTS: From 2006 to 2012, 4103 serum specimens were collected from occupational populations and the overall positive rate of H5/H7/H9 antibodies was 3.82% . The antibody positive rates for H5, H7 and H9 were 0.22% ,0.00% and 3.70% respectively. 4 serum specimens for H5 and H9 simultaneously showed antibody positive. The positive rate of H9 among occupational populations(4.21%)appeared higher than that from the control population(2.16%). 2028 specimens were collected from poultry sites and 55 samples found positive for H5 nucleic acid (positive rate:2.71%), 14 samples positive for H9 nucleic acid (positive rate:0.69%), 5 specimens, simultaneously positive for H5 and H9 nucleic acids. However, none of the samples showing H7 nucleic acid positive. From 2006 to 2012, all the tested H5/H7/H9 virus were negative from the respiratory/serum specimens among those close contacts of patients or high risk groups through the avian flu emergency surveillance program,ILI patient influenza virus surveillance programs or pneumonia of unknown causes surveillance program. CONCLUSION: Contamination of H5/H9 avian influenza virus did exist in the poultry sites in Guangzhou, especially in the wet Markets. The H5/H9 avian influenza virus caused asymptomatic infection was proved to be existed within the population exposed to the poultry, suggesting that the poultry occupational population in Guangzhou was under the risk of avian influenza virus infection.


Subject(s)
Influenza, Human/prevention & control , Influenza, Human/virology , Population Surveillance , Adult , Animals , China/epidemiology , Environmental Monitoring , Female , Humans , Influenza A virus , Influenza in Birds/epidemiology , Influenza, Human/epidemiology , Male , Middle Aged , Occupational Exposure/prevention & control , Poultry
15.
Zhonghua Yu Fang Yi Xue Za Zhi ; 47(12): 1089-94, 2013 Dec.
Article in Chinese | MEDLINE | ID: mdl-24529265

ABSTRACT

OBJECTIVE: To investigate the epidemic characteristics and pathogenic spectrum of community acquired pneumonia (CAP) in Guangzhou from 2009 to 2012. METHOD: 14 major comprehensive hospitals were selected from 11 districts as sentinel hospitals for CAP cases surveillance, including 18 982 223 in total during the 4 years. The characteristics of pathogenic spectrum of CAP were stratified and analyzed by year, age and season. RESULTS: 18 982 223 cases were included in the surveillance from year 2009 to 2012, in which 56 618 cases were CAP. The number of CAP cases increased from 8677 in year 2009 to 19 947 in year 2012 in Guangzhou; while the percentage of visits for CAP raised from 0.22% (8677/3 893 800) to 0.41% (19 947/4 839 766). The difference showed statistical significance (χ(2) = 2693.00, P < 0.05). Among the hospitalized CAP cases, 66.05% (10 954/16 585) were aged ≤ 5 years old or > 66 years old. The percentage of cases infected by a single pathogen was 88.11% (14 613/16 585), while co-infected cases accounted for 4.17% (691/16 585). Bacteria accounted for the largest proportion of 65.25% (10 821/16 585) as a single pathogen, followed by mycoplasma 13.54% (2245/16 585), virus 9.01% (1494/16 585) and chlamydia 0.32% (53/16 585). The proportion of virus infection was increasing from 4.74% to 11.64%. The difference showed statistical significance (χ(2) = 135.32, P < 0.05). Bacteria infection was the leading causes for CAP cases in all age groups; however the percentage increased with the increasing of ages. The rate of bacterial infection was increased from 48.35% (2993/6191) among children aged ≤ 5 years old to 81.31% (3873/4763) among adults aged over 65 years (χ(2) = 1632.00, P < 0.05). The rate of atypical pathogens (mycoplasma, chlamydia) for children ( ≤ 15 years old) (25.99%, 1805/6945) was higher than that for adults aged ≥ 16 years old (5.12%, 494/9640) (χ(2) = 2.11, P < 0.05). The effect from season on the pathogenic spectrum was not observed.433 hospitalized CAP cases were dead from 2009 to 2012. Case fatality rate was highest among people aged over 65 years old (4.70%, 224/4763) and lowest among children aged between 6 to 15 years old (0.27%, 2/754). CONCLUSION: The incidence of community acquired pneumonia was rising in Guangzhou from 2009 to 2012. Bacteria was the dominant pathogen. Children and old people were the high-risk population of community acquired pneumonia; while co-infection was still at low level.


Subject(s)
Community-Acquired Infections/epidemiology , Pneumonia/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , China/epidemiology , Community-Acquired Infections/microbiology , Female , Humans , Infant , Male , Middle Aged , Pneumonia/microbiology , Sentinel Surveillance , Young Adult
17.
Chinese Journal of Epidemiology ; (12): 900-905, 2013.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-320976

ABSTRACT

<p><b>OBJECTIVE</b>To analyze the results of avian influenza surveillance program in Guangzhou from 2006 to 2012 and to evaluate the risk of infections with H5, H7 and H9 subtypes avian influenza viruses.</p><p><b>METHODS</b>Avian influenza surveillance system in Guangzhou consisted five components:serum surveillance on occupational population, environmental specimen surveillance of avian influenza virus, avian flu emergency surveillance, influenza viruses surveillance on ILI patient and surveillance on pneumonia of unknown causes. Hemagglutination inhibition test was conducted to detect the antibodies against H5, H7 and H9 while RT-PCR was used to test the nucleic acid of H5, H7 and H9 viruses.</p><p><b>RESULTS</b>From 2006 to 2012, 4103 serum specimens were collected from occupational populations and the overall positive rate of H5/H7/H9 antibodies was 3.82% . The antibody positive rates for H5, H7 and H9 were 0.22% ,0.00% and 3.70% respectively. 4 serum specimens for H5 and H9 simultaneously showed antibody positive. The positive rate of H9 among occupational populations(4.21%)appeared higher than that from the control population(2.16%). 2028 specimens were collected from poultry sites and 55 samples found positive for H5 nucleic acid (positive rate:2.71%), 14 samples positive for H9 nucleic acid (positive rate:0.69%), 5 specimens, simultaneously positive for H5 and H9 nucleic acids. However, none of the samples showing H7 nucleic acid positive. From 2006 to 2012, all the tested H5/H7/H9 virus were negative from the respiratory/serum specimens among those close contacts of patients or high risk groups through the avian flu emergency surveillance program,ILI patient influenza virus surveillance programs or pneumonia of unknown causes surveillance program.</p><p><b>CONCLUSION</b>Contamination of H5/H9 avian influenza virus did exist in the poultry sites in Guangzhou, especially in the wet Markets. The H5/H9 avian influenza virus caused asymptomatic infection was proved to be existed within the population exposed to the poultry, suggesting that the poultry occupational population in Guangzhou was under the risk of avian influenza virus infection.</p>


Subject(s)
Adult , Animals , Female , Humans , Male , Middle Aged , China , Epidemiology , Environmental Monitoring , Influenza A virus , Influenza in Birds , Epidemiology , Influenza, Human , Epidemiology , Virology , Occupational Exposure , Population Surveillance , Poultry
18.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-355736

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the epidemic characteristics and pathogenic spectrum of community acquired pneumonia (CAP) in Guangzhou from 2009 to 2012.</p><p><b>METHOD</b>14 major comprehensive hospitals were selected from 11 districts as sentinel hospitals for CAP cases surveillance, including 18 982 223 in total during the 4 years. The characteristics of pathogenic spectrum of CAP were stratified and analyzed by year, age and season.</p><p><b>RESULTS</b>18 982 223 cases were included in the surveillance from year 2009 to 2012, in which 56 618 cases were CAP. The number of CAP cases increased from 8677 in year 2009 to 19 947 in year 2012 in Guangzhou; while the percentage of visits for CAP raised from 0.22% (8677/3 893 800) to 0.41% (19 947/4 839 766). The difference showed statistical significance (χ(2) = 2693.00, P < 0.05). Among the hospitalized CAP cases, 66.05% (10 954/16 585) were aged ≤ 5 years old or > 66 years old. The percentage of cases infected by a single pathogen was 88.11% (14 613/16 585), while co-infected cases accounted for 4.17% (691/16 585). Bacteria accounted for the largest proportion of 65.25% (10 821/16 585) as a single pathogen, followed by mycoplasma 13.54% (2245/16 585), virus 9.01% (1494/16 585) and chlamydia 0.32% (53/16 585). The proportion of virus infection was increasing from 4.74% to 11.64%. The difference showed statistical significance (χ(2) = 135.32, P < 0.05). Bacteria infection was the leading causes for CAP cases in all age groups; however the percentage increased with the increasing of ages. The rate of bacterial infection was increased from 48.35% (2993/6191) among children aged ≤ 5 years old to 81.31% (3873/4763) among adults aged over 65 years (χ(2) = 1632.00, P < 0.05). The rate of atypical pathogens (mycoplasma, chlamydia) for children ( ≤ 15 years old) (25.99%, 1805/6945) was higher than that for adults aged ≥ 16 years old (5.12%, 494/9640) (χ(2) = 2.11, P < 0.05). The effect from season on the pathogenic spectrum was not observed.433 hospitalized CAP cases were dead from 2009 to 2012. Case fatality rate was highest among people aged over 65 years old (4.70%, 224/4763) and lowest among children aged between 6 to 15 years old (0.27%, 2/754).</p><p><b>CONCLUSION</b>The incidence of community acquired pneumonia was rising in Guangzhou from 2009 to 2012. Bacteria was the dominant pathogen. Children and old people were the high-risk population of community acquired pneumonia; while co-infection was still at low level.</p>


Subject(s)
Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Young Adult , China , Epidemiology , Community-Acquired Infections , Epidemiology , Microbiology , Pneumonia , Epidemiology , Microbiology , Sentinel Surveillance
19.
Zhonghua Liu Xing Bing Xue Za Zhi ; 32(6): 554-8, 2011 Jun.
Article in Chinese | MEDLINE | ID: mdl-21781470

ABSTRACT

OBJECTIVE: To assess the relationship between cardiovascular risk factors and osteoporosis. METHODS: 2202 women aged 50 - 73 years were included in this cross-sectional study from the communities in Guangzhou, from July 2008 to January 2010. Cardiovascular risk factors including age, years since menopause, physical activity, anthropometrics, body composition, blood pressure, fasting serum lipids, glucose and uric acid, intima-media thickness (IMT) of carotid artery were assessed. Ultrasonic bone density (speed of sound) at the radius and tibia were determined. Osteoporosis was defined as T-score ≤ -2.5. Common factors for the cardiovascular risk factors were extracted using the factor analysis method. RESULTS: Eight common factors representing obesity, lean mass, blood triglycerides and uric acid, cholesterol, age, blood pressure, IMT and physical activity were extracted. Data from the Multivariate logistic regression showed a dose-dependent association of greater scores of age and IMT factors and lower score of lean mass factor with the increased risk of osteoporosis at the radius and tibia. As compared with the bottom quartile, the OR (95%CI) of radius and tibia osteoporosis were 0.62 (0.44 - 0.88) and 0.62 (0.48 - 0.80) for lean mass factor, 4.02 (2.72 - 5.94) and 3.68 (2.81 - 4.82) for age factor, 1.41 (1.00 - 2.00) and 1.54 (1.19 - 2.00) for IMT factors, respectively. Moreover, greater blood pressure score was associated with higher risk of radius osteoporosis while the higher obese score, was correlated with the increased risk of tibia osteoporosis. CONCLUSION: The cardiovascular-related risk factors of greater IMT, obesity, blood pressure and lower lean mass scores were associated with increased osteoporosis risks while called for more concern among the Chinese women.


Subject(s)
Cardiovascular Diseases/epidemiology , Osteoporosis, Postmenopausal/epidemiology , Aged , China/epidemiology , Cross-Sectional Studies , Female , Humans , Middle Aged , Risk Factors
20.
Chinese Journal of Epidemiology ; (12): 554-558, 2011.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-273142

ABSTRACT

Objective To assess the relationship between cardiovascular risk factors and osteoporosis. Methods 2202 women aged 50-73 years were included in this cross-sectional study from the communities in Guangzhou, from July 2008 to January 2010. Cardiovascular risk factors including age, years since menopause, physical activity, anthropometrics, body composition, blood pressure, fasting serum lipids, glucose and uric acid, intima-media thickness(IMT) of carotid artery were assessed. Ultrasonic bone density (speed of sound) at the radius and tibia were determined. Osteoporosis was defined as T-score≤-2.5. Common factors for the cardiovascular risk factors were extracted using the factor analysis method. Results Eight common factors representing obesity, lean mass, blood triglycerides and uric acid, cholesterol, age, blood pressure, IMT and physical activity were extracted. Data from the Multivariate logistic regression showed a dose-dependent association of greater scores of age and IMT factors and lower score of lean mass factor with the increased risk of osteoporosis at the radius and tibia. As compared with the bottom quartile, the OR (95%CI) of radius and tibia osteoporosis were 0.62 (0.44-0.88) and 0.62 (0.48-0.80) for lean mass factor, 4.02 (2.72-5.94) and 3.68(2.81-4.82) for age factor, 1.41 (1.00-2.00) and 1.54 (1.19-2.00) for IMT factors, respectively. Moreover, greater blood pressure score was associated with higher risk of radius osteoporosis while the higher obese score, was correlated with the increased risk of tibia osteoporosis. Conclusion The cardiovascular-related risk factors of greater IMT, obesity, blood pressure and lower lean mass scores were associated with increased osteoporosis risks while called for more concern among the Chinese women.

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