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1.
J Phys Chem Lett ; 14(11): 2750-2757, 2023 Mar 23.
Article in English | MEDLINE | ID: mdl-36897319

ABSTRACT

Biomass ethanol is regarded as a renewable resource but it is not economically viable to transform it to high-value industrial chemicals at present. Herein, a simple, green, and low-cost CuCl2-ethanol complex is reported for ethanol dehydration to produce ethylene and acetal simultaneously with high selectivity under sunlight irradiation. Under N2 atmosphere, the generation rates of ethylene and acetal were 165 and 3672 µmol g-1 h-1, accounting for 100% in gas products and 97% in liquid products, respectively. An outstanding apparent quantum yield of 13.2% (365 nm) and the maximum conversion rate of 32% were achieved. The dehydration reactions start from the photoexcited CuCl2-ethanol complex, and then go through the energy transfer (EnT) and ligand to metal charge transfer (LMCT) mechanisms to produce ethylene and acetal, respectively. The formation energies of the CuCl2-ethanol complex and the key intermediate radicals (e.g., ·OH, CH3CH2·, and CH3CH2O·) were validated to clarify the mechanisms. Different from previous CuCl2-based oxidation and addition reactions, this work is anticipated to supply new insights into the dehydration reaction of ethanol to produce useful chemical feedstocks.

2.
Small Methods ; 7(3): e2201467, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36631288

ABSTRACT

Post-treatment is an essential passivation step for the state-of-the-art perovskite solar cells (PSCs) but the additional role is not yet exploited. In this work, perovskite film is fabricated under ambient air with wide humidity window and identify that chloride redistribution induced by post-treatment plays an important role in high performance. The chlorine/iodine ratio on the perovskite surface increases from 0.037 to 0.439 after cyclohexylmethylammonium iodide (CHMAI) treatment and the PSCs deliver a champion power conversion efficiency (PCE) of 24.42% (certificated 23.60%). The maximum external quantum efficiency of electroluminescence (EQEEL ) reaches to 10.84% with a radiance of 170 W sr-1  m-2 , forming the reciprocity relation between EQEEL and nonradiative open-circuit voltage loss (86.0 mV). After thermal annealing, 2D component of perovskite will increase while chloride decline, leading to improved photovoltage but reduced fill factor. Hence, it distinguishes that chloride enrichment can improve charge transport/recombination simultaneously and 2D passivation can suppress the nonradiative recombination. Moreover, CHMAI can leverage their roles in charge transport/recombination for better performance than phenylethylammonium iodide (Cl/I = 0.114, PCE = 23.32%), due to the stronger binding energy of Cl- . This work provides the insight that the chloride fixation can improve the photovoltaic performance.

3.
Lancet Reg Health West Pac ; 8: 100094, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33585828

ABSTRACT

BACKGROUND: China implemented containment measures to stop SARS-CoV-2 transmission in response to the COVID-19 epidemic. After the first epidemic wave, we conducted population-based serological surveys to determine extent of infection, risk factors for infection, and neutralization antibody levels to assess the real infections in the random sampled population. METHODS: We used a multistage, stratified cluster random sampling strategy to conduct serological surveys in three areas - Wuhan, Hubei Province outside Wuhan, and six provinces selected on COVID-19 incidence and containment strategy. Participants were consenting individuals >1 year old who resided in the survey area >14 days during the epidemic. Provinces screened sera for SARS-CoV-2-specific IgM, IgG, and total antibody by two lateral flow immunoassays and one magnetic chemiluminescence enzyme immunoassay; positive samples were verified by micro-neutralization assay. FINDINGS: We enrolled 34,857 participants (overall response rate, 92%); 427 were positive by micro-neutralization assay. Wuhan had the highest weighted seroprevalence (4•43%, 95% confidence interval [95%CI]=3•48%-5•62%), followed by Hubei-ex-Wuhan (0•44%, 95%CI=0•26%-0•76%), and the other provinces (<0•1%). Living in Wuhan (adjusted odds ratio aOR=13•70, 95%CI= 7•91-23•75), contact with COVID-19 patients (aOR=7•35, 95%CI=5•05-10•69), and age over 40 (aOR=1•36, 95%CI=1•07-1•72) were significantly associated with SARS-CoV-2 infection. Among seropositives, 101 (24%) reported symptoms and had higher geometric mean neutralizing antibody titers than among the 326 (76%) without symptoms (30±2•4 vs 15±2•1, p<0•001). INTERPRETATION: The low overall extent of infection and steep gradient of seropositivity from Wuhan to the outer provinces provide evidence supporting the success of containment of the first wave of COVID-19 in China. SARS-CoV-2 infection was largely asymptomatic, emphasizing the importance of active case finding and physical distancing. Virtually the entire population of China remains susceptible to SARS-CoV-2; vaccination will be needed for long-term protection. FUNDING: This study was supported by the Ministry of Science and Technology (2020YFC0846900) and the National Natural Science Foundation of China (82041026, 82041027, 82041028, 82041029, 82041030, 82041032, 82041033).

4.
Hepatology ; 72(2): 389-398, 2020 08.
Article in English | MEDLINE | ID: mdl-32359177

ABSTRACT

BACKGROUND AND AIMS: Coronavirus disease 2019 (COVID-19) is a new infectious disease. To reveal the hepatic injury related to this disease and its clinical significance, we conducted a multicenter retrospective cohort study that included 5,771 adult patients with COVID-19 pneumonia in Hubei Province. APPROACH AND RESULTS: We reported the distributional and temporal patterns of liver injury indicators in these patients and determined their associated factors and death risk. Longitudinal liver function tests were retrospectively analyzed and correlated with the risk factors and death. Liver injury dynamic patterns differed in alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and total bilirubin (TBIL). AST elevated first, followed by ALT, in severe patients. ALP modestly increased during hospitalization and largely remained in the normal range. The fluctuation in TBIL levels was mild in the non-severe and the severe groups. AST abnormality was associated with the highest mortality risk compared with the other indicators of liver injury during hospitalization. Common factors associated with elevated liver injury indicators were lymphocyte count decrease, neutrophil count increase, and male gender. CONCLUSION: The dynamic patterns of liver injury indicators and their potential risk factors may provide an important explanation for the COVID-19-associated liver injury. Because elevated liver injury indicators, particularly AST, are strongly associated with the mortality risk, our study indicates that these parameters should be monitored during hospitalization.


Subject(s)
Betacoronavirus , Coronavirus Infections/mortality , Coronavirus Infections/physiopathology , Liver/physiopathology , Pneumonia, Viral/mortality , Pneumonia, Viral/physiopathology , Adult , Aged , Alanine Transaminase/blood , Alkaline Phosphatase/blood , Aspartate Aminotransferases/blood , Bilirubin/blood , Biomarkers , COVID-19 , Female , Humans , Longitudinal Studies , Male , Middle Aged , Pandemics , Retrospective Studies , SARS-CoV-2
5.
Vaccine ; 38(16): 3210-3217, 2020 04 03.
Article in English | MEDLINE | ID: mdl-32173094

ABSTRACT

INTRODUCTION: Endemic measles persists in China, despite >95% reported coverage of two measles-containing vaccine doses and nationwide campaign that vaccinated >100 million children in 2010. An increasing proportion of infections now occur among adults and there is concern that persistent susceptibility in adults is an obstacle to measles elimination in China. We performed a case-control study in six Chinese provinces between January 2012 to June 2013 to identify risk factors for measles virus infection and susceptibility among adults. METHODS: Persons ≥15 years old with laboratory-confirmed measles were age and neighborhood matched with three controls. Controls had blood specimens collected to determine their measles IgG serostatus. We interviewed case-patients and controls about potential risk factors for measles virus infection and susceptibility. Unadjusted and adjusted matched odds ratios and 95% confidence intervals (CIs) were calculated via conditional logistic regression. We calculated attributable fractions for infection for risk factors that could be interpreted as causal. RESULTS: 899 cases and 2498 controls were enrolled. Among controls, 165 (6.6%) were seronegative for measles IgG indicating persistent susceptibility to infection. In multivariable analysis, hospital visit and travel outside the prefecture in the prior 1-3 weeks were significant risk factors for measles virus infection. Occupation and reluctance to accept measles vaccination were significant risk factors for measles susceptibility. The calculated attributable fraction of measles cases from hospital visitation was 28.6% (95% CI: 20.6-38.8%). CONCLUSIONS: Exposure to a healthcare facility was the largest risk factor for measles virus infection in adults in China. Improved adherence to hospital infection control practices could reduce risk of ongoing measles virus transmission and increase the likelihood of achieving and sustaining measles elimination in China. The use of control groups stratified by serological status identified distinct risk factors for measles virus infection and susceptibility among adults.


Subject(s)
Measles virus , Measles , Adolescent , Adult , Case-Control Studies , Child , China/epidemiology , Disease Outbreaks , Humans , Infant , Measles/epidemiology , Measles/prevention & control , Measles Vaccine , Risk Factors , Vaccination
8.
MMWR Morb Mortal Wkly Rep ; 68(48): 1112-1116, 2019 Dec 06.
Article in English | MEDLINE | ID: mdl-31805034

ABSTRACT

In 2005, the World Health Organization (WHO) Western Pacific Region countries, including China, resolved to eliminate measles by 2012 or as soon as feasible thereafter (1). As of 2018, nine* of the 37 Western Pacific Region countries or areas† had eliminated§ measles. China's Measles Elimination Action Plan 2006-2012 included strengthening routine immunization; conducting measles risk assessments, followed by supplementary immunization activities (SIAs) with measles-containing vaccine (MCV) at national and subnational levels; strengthening surveillance and laboratory capacity; and investigating and responding to measles outbreaks. Most recently, progress toward measles elimination in China was described in a 2014 report documenting measles elimination efforts in China during 2008-2012 and a resurgence in 2013 (2). This report describes progress toward measles elimination in China during January 2013-June 2019.¶ Measles incidence per million persons decreased from 20.4 in 2013 to 2.8 in 2018; reported measles-related deaths decreased from 32 in 2015 to one in 2018 and no deaths in 2019 through June. Measles elimination in China can be achieved through strengthening the immunization program's existing strategy by ensuring sufficient vaccine supply; continuing to improve laboratory-supported surveillance, outbreak investigation and response; strengthening school entry vaccination record checks; vaccinating students who do not have documentation of receipt of 2 doses of measles-rubella vaccine; and vaccinating health care professionals and other adults at risk for measles.


Subject(s)
Disease Eradication , Disease Outbreaks/prevention & control , Measles/prevention & control , Population Surveillance , Adolescent , Child , Child, Preschool , China/epidemiology , Disease Outbreaks/statistics & numerical data , Female , Humans , Immunization Programs , Incidence , Infant , Male , Measles/epidemiology , Measles/mortality , Measles Vaccine/administration & dosage
9.
China CDC Wkly ; 1(2): 21-25, 2019 Dec.
Article in English | MEDLINE | ID: mdl-34594595

ABSTRACT

What is already known about this topic? China has historically had high measles incidence and many associated deaths. A comprehensive measles elimination plan during 2006-2012 substantially reduced measles incidence; however, a resurgence occurred during 2013-2015. What is added by this report? In China, measles surveillance, outbreak response, research, and program evaluation were used to strengthen routine immunization and target immunization activities for eliminating measles. Measles incidence declined from 31 per million in 2015 to 2.8 in 2018; only one measles-associated death has been reported during 2018-June 2019. What are the implications for public health practice? The World Health Organization-recommended strategy to eliminate measles can be effective, including in large, densely populated countries like China.

10.
Int Urol Nephrol ; 50(7): 1285-1292, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29549623

ABSTRACT

BACKGROUND: Tonsillitis can promote the progression of IgA nephropathy (IgAN) by aggravating immunopathologic response. Th22 cell disorder is involved in the pathogenesis of IgAN with tonsillitis. This study was determined to explore the possible mechanism of IgAN with tonsillitis underlying Th22 cell chemotaxis response to the effect of CCL20, CCL22, and CCL27. METHODS: This research was conducted on 65 subjects including 16 healthy controls (HC group), 5 patients with  renal carcinoma (HTC group) and 44 patients with IgAN between 2015 and 2016. According to clinical symptoms and results of throat swab culture, patients with IgAN were divided into two groups: IgAN with tonsillitis (IgAN + tonsillitis, n = 14) and IgAN patients without tonsillitis (IgAN, n = 30). Distribution of Th22 cells in IgAN patients was determined. The expression of CCL20, CCL22, and CCL27 in both peripheral blood and kidneys of IgAN patients was investigated. Severity of pathological lesions in IgAN patients was analyzed. Coculture assay and transwell assay were performed to explore the impacts of human mesangial cells (HMC) on Th22 cell chemotaxis and Th22 cell local accumulation under hemolytic streptococcus (HS) infection. RESULTS: Th22 cell percentages in IgAN patients increased compared with healthy controls. This increased Th22 cell percentage was positively correlated with the renal lesions of IgAN patients. Correspondingly, the expression of CCL20, CCL22, and CCL27 in renal tissue increased in IgAN patients. Tonsillitis exacerbated these overrepresentations of Th22 cells and chemokines. It was found that HMC could produce CCL20, CCL22, and CCL27. The supernatant of HMC was chemotactic for Th22 cells. This activity of HMC was stimulated by HS infection, whereas treatment of anti-CCL20, anti-CCL22, and anti-CCL27 antibodies partly blocked this chemoattractant effect of HMC. CONCLUSIONS: Tonsil infection may aggravate the renal pathological lesions of IgAN by exacerbating Th22 cell accumulation. Our data suggested a collaboration between HMC and Th22 cells in IgAN with tonsillitis underlying the effects of CCL20, CCL22, and CCL27.


Subject(s)
Acute Kidney Injury/etiology , Chemokine CCL22/immunology , Glomerulonephritis, IGA/complications , Glomerulonephritis, IGA/pathology , Th2 Cells/immunology , Tonsillitis/complications , Acute Kidney Injury/pathology , Acute Kidney Injury/physiopathology , Adult , Analysis of Variance , Biopsy, Needle , Case-Control Studies , Cells, Cultured , Chemokine CCL22/metabolism , Chemotaxis/immunology , Coculture Techniques , Disease Progression , Enzyme-Linked Immunosorbent Assay , Female , Flow Cytometry , Glomerulonephritis, IGA/diagnosis , Humans , Immunohistochemistry , Male , Statistics, Nonparametric , Th2 Cells/metabolism , Tonsillitis/diagnosis
11.
BMC Infect Dis ; 17(1): 742, 2017 12 02.
Article in English | MEDLINE | ID: mdl-29197328

ABSTRACT

BACKGROUND: The goal of polio eradication is to complete elimination and containment of all wild, vaccine-related and Sabin polioviruses. Vaccine-derived poliovirus (VDPV) surveillance in China from 2001-2013 is summarized in this report, which has important implications for the global polio eradication initiative. METHODS: Acute flaccid paralysis (AFP) cases and their contacts with VDPVs isolated from fecal specimens were identified in our AFP surveillance system or by field investigation. Epidemiological and laboratory information for these children were analyzed and the reasons for the VDPV outbreak was explored. RESULTS: VDPVs were isolated from a total of 49 children in more than two-thirds of Chinese provinces from 2001-2013, including 15 VDPV cases, 15 non-polio AFP cases and 19 contacts of AFP cases or healthy subjects. A total of 3 circulating VDPVs (cVDPVs) outbreaks were reported in China, resulting in 6 cVDPVs cases who had not been vaccinated with oral attenuated poliomyelitis vaccine. Among the 4 immunodeficiency-associated VDPVs (iVDPVs) cases, the longest duration of virus excretion was about 20 months. In addition, one imported VDPV case from Myanmar was detected in Yunnan Province. CONCLUSIONS: Until all wild, vaccine-related and Sabin polioviruses are eradicated in the world, high quality routine immunization and sensitive AFP surveillance should be maintained, focusing efforts on underserved populations in high risk areas.


Subject(s)
Disease Eradication , Paralysis/epidemiology , Paralysis/virology , Poliovirus Vaccines/immunology , Antibodies, Viral/blood , Child , Child, Preschool , China/epidemiology , Female , Healthy Volunteers , Humans , Infant , Male , Myanmar , Poliomyelitis/epidemiology , Poliomyelitis/prevention & control , Poliovirus/immunology , Poliovirus Vaccine, Oral/therapeutic use , Poliovirus Vaccines/therapeutic use , Time Factors , Vaccination Coverage
12.
PLoS Med ; 14(4): e1002255, 2017 04.
Article in English | MEDLINE | ID: mdl-28376084

ABSTRACT

BACKGROUND: Industrialization and demographic transition generate nonstationary dynamics in human populations that can affect the transmission and persistence of infectious diseases. Decades of increasing vaccination and development have led to dramatic declines in the global burden of measles, but the virus remains persistent in much of the world. Here we show that a combination of demographic transition, as a result of declining birth rates, and reduced measles prevalence, due to improved vaccination, has shifted the age distribution of susceptibility to measles throughout China. METHODS AND FINDINGS: We fit a novel time-varying catalytic model to three decades of age-specific measles case reporting in six provinces in China to quantify the change in the age-specific force of infection for measles virus over time. We further quantified the impact of supplemental vaccination campaigns on the reduction of susceptible individuals. The force of infection of measles has declined dramatically (90%-97% reduction in transmission rate) in three industrialized eastern provinces during the last decade, driving a concomitant increase in both the relative proportion and absolute number of adult cases, while three central and western provinces exhibited dynamics consistent with endemic persistence (24%-73% reduction in transmission rate). The reduction in susceptible individuals due to supplemental vaccination campaigns is frequently below the nominal campaign coverage, likely because campaigns necessarily vaccinate those who may already be immune. The impact of these campaigns has significantly improved over time: campaigns prior to 2005 were estimated to have achieved less than 50% reductions in the proportion susceptible in the target age classes, but campaigns from 2005 onwards reduced the susceptible proportion by 32%-87%. A limitation of this study is that it relies on case surveillance, and thus inference may be biased by age-specific variation in measles reporting. CONCLUSIONS: The age distribution of measles cases changes in response to both demographic and vaccination processes. Combining both processes in a novel catalytic model, we illustrate that age-specific incidence patterns reveal regional differences in the progress to measles elimination and the impact of vaccination controls in China. The shift in the age distribution of measles susceptibility in response to demographic and vaccination processes emphasizes the importance of progressive control strategies and measures to evaluate program success that anticipate and react to this transition in observed incidence.


Subject(s)
Measles/epidemiology , Models, Theoretical , Population Dynamics , Adult , Age Distribution , Child , China/epidemiology , Humans , Incidence , Measles/prevention & control , Measles/transmission , Measles Vaccine/therapeutic use , Vaccination/statistics & numerical data
14.
Vaccine ; 34(51): 6553-6560, 2016 12 12.
Article in English | MEDLINE | ID: mdl-27013438

ABSTRACT

INTRODUCTION: Endemic measles persists in China, despite >95% reported coverage of two measles-containing vaccine doses and nationwide campaign that vaccinated more than 100 million children in 2010. We performed a case-control study in six Chinese provinces during January 2012 through June 2013 to identify risk factors for measles infection among children aged 0-7 months. METHODS: Children with laboratory-confirmed measles were neighborhood matched with three controls. We interviewed parents of case and control infants on potential risk factors for measles. Adjusted matched odds ratios (mOR) and 95% confidence intervals (CIs) were calculated by multivariable conditional logistic modeling. We calculated attributable fractions for risk factors that could be interpreted as causal. RESULTS: Eight hundred thirty cases and 2303 controls were enrolled. In multivariable analysis, male sex (mOR 1.6 [1.3, 2.0]), age 5-7 months (mOR 3.9 [3.0, 5.1]), migration between counties (mOR 2.3 [1.6, 3.4]), outpatient hospital visits (mOR 9.4 [6.6, 13.3]) and inpatient hospitalization (mOR 107.1 [48.8, 235.1]) were significant risk factors. The calculated attributable fractions for hospital visits was 43.1% (95% CI: 40.1, 47.5%) adjusted for age, sex and migration. CONCLUSIONS: Hospital visitation was the largest risk factor for measles infection in infants. Improved hospital infection control practices would accelerate measles elimination in China.


Subject(s)
Measles/epidemiology , Case-Control Studies , China/epidemiology , Female , Humans , Infant , Infant, Newborn , Male , Risk Factors
15.
PLoS One ; 11(2): e0149468, 2016.
Article in English | MEDLINE | ID: mdl-26894876

ABSTRACT

BACKGROUND: The disease burden associated with influenza in developing tropical and subtropical countries is poorly understood owing to the lack of a comprehensive disease surveillance system and information-exchange mechanisms. The impact of influenza on outpatient visits, hospital admissions, and deaths has not been fully demonstrated to date in south China. METHODS: A time series Poisson generalized additive model was used to quantitatively assess influenza-like illness (ILI) and influenza disease burden by using influenza surveillance data in Zhuhai City from 2007 to 2009, combined with the outpatient, inpatient, and respiratory disease mortality data of the same period. RESULTS: The influenza activity in Zhuhai City demonstrated a typical subtropical seasonal pattern; however, each influenza virus subtype showed a specific transmission variation. The weekly ILI case number and virus isolation rate had a very close positive correlation (r = 0.774, P < 0.0001). The impact of ILI and influenza on weekly outpatient visits was statistically significant (P < 0.05). We determined that 10.7% of outpatient visits were associated with ILI and 1.88% were associated with influenza. ILI also had a significant influence on the hospitalization rates (P < 0.05), but mainly in populations <25 years of age. No statistically significant effect of influenza on hospital admissions was found (P > 0.05). The impact of ILI on chronic obstructive pulmonary disease (COPD) was most significant (P < 0.05), with 33.1% of COPD-related deaths being attributable to ILI. The impact of influenza on the mortality rate requires further evaluation. CONCLUSIONS: ILI is a feasible indicator of influenza activity. Both ILI and influenza have a large impact on outpatient visits. Although ILI affects the number of hospital admissions and deaths, we found no consistent influence of influenza, which requires further assessment.


Subject(s)
Cost of Illness , Hospitalization/statistics & numerical data , Influenza, Human/economics , Aged , Ambulatory Care/statistics & numerical data , China/epidemiology , Female , Humans , Influenza, Human/epidemiology , Influenza, Human/mortality , Influenza, Human/virology , Male , Middle Aged , Models, Statistical , Poisson Distribution , Respiratory Tract Infections/economics
16.
Vaccine ; 34(51): 6545-6552, 2016 12 12.
Article in English | MEDLINE | ID: mdl-26876440

ABSTRACT

INTRODUCTION: Endemic measles persists in China, despite >95% reported coverage of two measles-containing vaccine doses and nationwide campaign that vaccinated more than 100 million children in 2010. In 2011, almost half of the 9943 measles cases in China occurred in children eligible for measles vaccination. We conducted a case-control study during 2012-2013 to identify risk factors for measles infection in children aged 8 months-14 years. METHODS: Children with laboratory-confirmed measles were age- and neighborhood-matched with three controls. We interviewed parents of case and control infants on potential risk factors for measles. We calculated adjusted matched odds ratios and 95% confidence intervals of risk factors. We calculated attributable fractions for risk factors that could be interpreted as causal and vaccine efficacy (VE) for the measles containing vaccine (MCV) used in the Chinese immunization program. RESULTS: In all, 969 case-patients and 2845 controls were enrolled. In multivariable analysis, lack of measles vaccination both overall (mOR 22.7 [16.6, 31.1] and when stratified by region (east region, mOR 74.2 [27.3, 202]; central/western regions mOR 17.4 [12.5, 24.3]), hospital exposure (mOR 63.0, 95% CI [32.8, 121]), and migration among counties (overall mOR 3.0 [2.3, 3.9]) were significant risk factors. The calculated VE was 91.9-96.1% for a single dose of MCV and 96.6-99.5% for 2 doses. CONCLUSIONS: Lack of vaccination was the leading risk factor for measles infection, especially in children born since the 2010 supplementary immunization activity. Reducing missed vaccination opportunities, improving immunization access for migrant children, and strengthening school/kindergarten vaccine checks are needed to strengthen the routine immunization program and maintain progress toward measles elimination in China.


Subject(s)
Measles Vaccine/administration & dosage , Measles/epidemiology , Measles/prevention & control , Vaccination/statistics & numerical data , Adolescent , Case-Control Studies , Child , Child, Preschool , China/epidemiology , Female , Humans , Infant , Male , Risk Factors
17.
Article in English | MEDLINE | ID: mdl-24857374

ABSTRACT

Counterfeits in the medicine market make the authentication of snakes used for Chinese medicine a challenge to Chinese drug regulatory control agencies. This paper explores existing methods that can be used to quickly and accurately distinguish Zaocys (Z. dhumnades) from its counterfeits for routine identification of snake meats in food and drug control laboratories. In this research, the Cytochrome Oxidase I (COI) fragments of 51 samples from 17 species of snakes were amplified using Polymerase Chain Reaction (PCR) and sequenced. The inter- and intra-specific variations of COI sequences were analyzed and compared based on Kimura-2-parameter (K-2P) distances; the minimal interspecific K-2P distance was 0.0934, which was bigger than the maximum intraspecific K-2P distance in Z. dhumnades (0.0523), indicating that Zaocys can be separated from its counterfeits. The Neighbor-Joining (N-J) tree of the snakes was constructed and the results show that snakes of the same species cluster with 100% bootstrap values. Since the Zaocys and its counterfeits are of different species, they can be distinguished using the N-J tree method. Another 10 samples of Zaocys from markets and drug stores were identified at the species level, among which 5 samples were proven to be the counterfeits--Ptyas korros.


Subject(s)
DNA Barcoding, Taxonomic , Electron Transport Complex IV/genetics , Snakes/genetics , Animals , Medicine, Chinese Traditional , Phylogeny , Species Specificity
18.
Zhonghua Liu Xing Bing Xue Za Zhi ; 36(6): 629-33, 2015 Jun.
Article in Chinese | MEDLINE | ID: mdl-26564639

ABSTRACT

OBJECTIVE: To identify the cause of an outbreak of foot pain syndrome among students from a senior high school in Foshan. METHODS: We defined a suspect case as onset of foot pain/numbness with unknown reason among students and teachers in a school of Foshan city, from February 10 to March 16, 2014. A suspect case was noticed as having both food pain and numbness. All the cases were searched through reviewing medical records in the nearby hospitals and school's clinic, also the records of absenteeism in school. Clinical information was collected from all the students, using a standardized questionnaire. Daily temperature was collected from all the students, between January 1 and March 31, 2014. A 1 : 2 individual matched case-control study was conducted to identify related risk factors on this epidemic. We interviewed all the cases and controls on their diet, physical activities and measures used for warming. RESULTS: A total of 407 case-students were identified, with an attack rate (AR) as 26.5%. The AR was 37.3% in girls, compared to 12.9% in boys. The difference was statistically significant (χ² = 115.1, P < 0.01). Boarding students had a higher AR (31.8%) than the commuting students (16.2%). The difference was statistically significant (χ² = 43.2, P < 0.01). In girls, boarding students had higher AR (46.1%) than those commuting students (18.5%). The difference was statistically significant (χ² = 61.4, P < 0.01). No statistically significant difference was found between boarding or commuting students in boys. Outdoor temperature was coming down from 23 °C on February 6 to 6 °C on February 13, but gradually rose to 23 °C on February 28. There was a positive relationship (r = 0.65, P = 0.002) noticed between daily maximum temperature and the number of cases during February 13-28. Results from this case-control study showed that factors as lacking physical activities (OR = 2.8, 95% CI: 1.5-5.6), feeling cold in bed (OR = 3.0, 95% CI: 1.3-7.0) and having experienced similar symptoms (OR = 3.4, 95% CI: 1.1-11.0) could increase the risk of this disease. CONCLUSION: This outbreak was possibly caused by the abrupt fluctuation of temperature within a short period.


Subject(s)
Disease Outbreaks , Foot Diseases/epidemiology , Pain/epidemiology , Schools , Students/statistics & numerical data , Case-Control Studies , China/epidemiology , Female , Humans , Male , Residence Characteristics/statistics & numerical data , Risk Factors , Surveys and Questionnaires , Syndrome , Temperature , Time Factors , Transportation/statistics & numerical data
19.
PLoS One ; 10(7): e0133983, 2015.
Article in English | MEDLINE | ID: mdl-26208216

ABSTRACT

BACKGROUND: A measles outbreak occurred in a western county of China in 2013, the year after China's historic nadir of measles. We conducted a field investigation to identify gaps in measles vaccination coverage and immunization program weaknesses, and to provide recommendations for measles outbreak response and immunization program improvement. METHODS: We analyzed surveillance data from 2008 to 2013 to describe the measles epidemiology of the county. Measles-containing vaccine coverage was estimated using two methods: previously-reported administrative coverage and an estimation of coverage by clinic-kept vaccination records (n = 542). We conducted a rapid field coverage assessment in a migrant population village to evaluate coverage after emergency vaccination. We conducted a review of hospital records of measles cases to address the role hospital transmission played during the early stage of this outbreak. RESULTS: There were 153 cases in the outbreak, primarily among children too young to vaccinate, unvaccinated children less than 3 years old, and adults. Measles-containing vaccine coverage by the field assessment showed that 20% of children aged 8-17 months had zero doses, and 9% of ≥2 years old children had fewer than two doses. The vaccination statuses of all adult cases were either zero doses or unknown. At least 61% of cases had been hospitalized. The proportion of cases who had been hospital-exposed 7 to 21 days prior to rash onset decreased from 52% to 22% after hospitals strengthen their isolation measures. CONCLUSIONS: This outbreak was a result of measles vaccination coverage gaps among young children and adults, and insufficient hospital isolation of cases. The lower coverage seen in the field estimation compared with reported coverage showed that reported coverage could have been overestimated. Hospitals were sites of transmission in the early stage of the outbreak. A strict hospital isolation policy could decrease spread of measles. Emergency vaccination was associated with stopping measles transmission in low coverage areas.


Subject(s)
Disease Outbreaks , Measles Vaccine , Measles/epidemiology , Adolescent , Adult , Child , Child, Preschool , China , Female , History, 21st Century , Hospitalization , Humans , Infant , Infant, Newborn , Male , Measles/history , Measles/prevention & control , Measles/transmission , Measles Vaccine/immunology , Population Surveillance , Seasons , Vaccination , Young Adult
20.
Pediatrics ; 135(4): e1032-7, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25733758

ABSTRACT

In July 2013, the National Immunization Program of China was notified by the US Centers for Disease Control and Prevention that measles was detected in 3 newly adopted, special needs children with cerebral palsy (CP) from China. We report an investigation of measles transmission in China that led to infection of these children. Interviews were conducted with welfare institute staff and panel physicians; health records of the potentially exposed population were reviewed; and immunization coverage was assessed among institute residents. Five residents with CP, all unvaccinated against measles, among who were the 3 adoptees, were linked epidemiologically into 3 generations of measles transmission antecedent to the US outbreak. In a random sample of residents, first dose of measles containing vaccine (MCV1) and MCV2 coverage was 16 of 17 (94%) and 7 of 11 (64%) among children with CP, and 100% (32 of 32) and 96% (21 of 22) among children without CP. Vaccinators reported reluctance to vaccinate children with CP because the China pharmacopeia lists encephalopathy as a contraindication to vaccination. Panel physicians reported to investigators no necessity of vaccination for adoptees to the United States if US parents sign an affidavit exempting the child from vaccination. We recommend that the China pharmacopeia vaccine contraindications be reviewed and updated, the United States should reconsider allowing vaccination exemptions for internationally adopted children unless there are true medical contraindications to vaccination, and US pediatricians should counsel adopting parents to ensure that their child is up-to-date on recommended vaccinations before coming to the United States.


Subject(s)
Adoption , Asian People/statistics & numerical data , Cerebral Palsy/epidemiology , Disease Outbreaks , Measles/epidemiology , Measles/transmission , Brain Injuries/epidemiology , Brain Injuries/ethnology , Cerebral Palsy/ethnology , Child , Child, Preschool , China/ethnology , Cross-Sectional Studies , Female , Humans , Immunization Programs , Infant , Male , Measles/ethnology , Measles/prevention & control , Measles Vaccine/administration & dosage , Rehabilitation Centers/statistics & numerical data , United States
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