1.Sample Preparation and Imaging of Single Adenovirus Particle Using Atomic Force Microscopy in Liquid.
Yan LIANG ; Li CHEN ; Mariska G M van ROSMALEN ; Gijs J L WUITE ; Wouter H ROOS
Chinese Journal of Virology 2015;31(6):601-606
Atomic force microscopy (AFM), as a sophisticated imaging tool with nanoscale resolution, is widely used in virus research and the application of functional viral particles. To investigate single viruses by AFM in a physiologically relevant environment (liquid), an appropriate surface treatment to properly adhere the viruses to the substrate is essential. Here we discuss hydrophobic treated glass coverslips as a suitable substrate for the adhesion of single adenovirus particle (Adenovirus type 5 F35, Ad5F35) when studied with AFM in liquid. From the high resolution AFM images, the orientation of the adhered virus particles can be distinguished. Furthermore, the particles exhibit the expected height of -90 nm. This illustrates that the viruses adhere to the substrate firmly without large deformations. Hence, the described method works well on (fragile) viruses. The described experimental approach can be widely used for AFM studies in liquid of virus structure and mechanics as well as for investigating the interaction of viruses with cellular receptors.
Adenoviridae
;
chemistry
;
Imaging, Three-Dimensional
;
Microscopy, Atomic Force
;
methods
;
Virion
;
chemistry
3.Mitochondrial DNA and STR analyses for human DNA from maggots crop contents: A forensic entomology case from central-southern China
Li, X. ; Cai, J.F.* ; Guo, Y.D. ; Xiong, F. ; Zhang, L. ; Feng, H. ; Meng, F.M. ; Fu, Y. ; Li, J.B. ; Chen, Y.Q.
Tropical Biomedicine 2011;28(2):333-338
Insect larvae and adult insects found on human corpses can provide important
forensic evidence however it is useful to be able to prove evidence of association. Without
this, it could be claimed that the insect evidence was a contaminant or had been planted on
the body. This paper describes how mitochondrial DNA (mtDNA) and STR analysis of the crop
contents of larvae of the blowfly Aldrichina grahami collected from separated body parts
was used to provide evidence of association.
4.Analysis on long-term trends of cervical cancer mortality and years of life lost in Tianjin, 1999-2015.
W L ZHENG ; H ZHANG ; D Z WANG ; S ZHANG ; S PANG ; C K LI ; G H JIANG
Chinese Journal of Epidemiology 2019;40(1):64-69
Objective: To analyze the mortality and years of life lost (YLL) trends of cervical cancer in Tianjin, and provide references for the research and prevention programs of cervical cancer. Methods: Mortality rate, standard mortality rate, cumulative rate (0-74 years-old) and truncated rate (35-64 years-old) of cervical cancer from 1999 to 2015 were calculated. The annual percentage change of the mortality rate and YLL rate were analyzed by using Joinpoint regression analysis, and the trend in different age-groups were analyzed. Results: From 1999 to 2015, 1 741 cases died of cervical cancer in Tianjin, the average crude mortality rate was 2.15/100 000. The average age-standardized rate of (ASR) China and ASR world were 1.47/100 000 and 1.50/100 000 respectively. The average YLL was 3 347.97 person-years. Deaths occurred in those aged 0-34 years, 35-64 years and 65 years and over accounted for 3.10%, 57.84% and 39.06% of the total, respectively. The mortality rate of cervical cancer in urban area was higher than that in rural area, with a ratio of 1.37∶1 between urban area and rural area. The age-specific mortality rate of cervical cancer during 1999-2015 increased with age. Two peaks of mortality rate were observed in those aged 50 years and aged 75 years, during 2014-2015. From 1999 to 2011, the mortality rate of cervical cancer was stable (APC=-0.2%, P=0.80), but there was a rapid increase from 2011 to 2015 (APC=21.6%, P<0.01). But group aged 20-49 years, it showed an upward trend from 1999 to 2015 (APC=6.9%, P<0.01). For group aged 50-69 years, it showed a downward trend from 1999 to 2007 (APC=-9.2%, P<0.01), and an upward trend from 2007 to 2015 (APC=14.5%, P<0.01). For group aged 70 years and over, it showed a downward trend from 1999 to 2009 (APC=-10.2%, P<0.01), but the difference in the mortality were not significant from 2009 to 2015 (APC=7.8%, P=0.10). Since 2008, the YLL rate of cervical cancer in group aged 50-70 years had exceeded that in group aged >70 years and the gap gradually widened. Conclusions: There had been a rapid increase trend of cervical cancer mortality since 2011 in Tianjin. Women aged 50-70 years were the main group of life loss.
Adolescent
;
Adult
;
Aged
;
China/epidemiology*
;
Female
;
Humans
;
Incidence
;
Middle Aged
;
Mortality/trends*
;
Regression Analysis
;
Residence Characteristics
;
Survival Rate/trends*
;
Uterine Cervical Neoplasms/mortality*
;
Young Adult
5.Transmission cluster and network of HIV-1 CRF01_AE strain in China, 1996-2014.
X L WANG ; L JIA ; H P LI ; Y J LIU ; J W HAN ; T Y LI ; J Y LI ; L LI
Chinese Journal of Epidemiology 2019;40(1):84-88
Objective: To understand the transmission patterns and risk factors of HIV-1 strain CRF01_AE subtypes in China, and to provide guidance for the implementation of precise intervention. Methods: A total of 2 094 CRF01_AE pol sequences were collected in 19 provinces in China between 1996 and 2014. Phylogenetic tree was constructed by PhyML 3.0 software to select the transmission clusters. Transmission network was constructed by Cytoscape 3.6.0, which was further used for exploring of the major risk factors. Results: Of the 2 094 sequences, 12.18% (255/2 094) were in clusters. A total of 82 transmission clusters were identified. The numbers of clusters and contained sequences in intra-provincial transmission (61, 173) were significantly more than those in inter-provincial transmission (21, 82). The ratio of transmission clustering in MSM increased over time from 2.41% (2/83) during 1996-2008 to 23.61% (72/305) during 2013-2014, showing a significant upward trend (χ(2)=27.800, df=1, P=0.000). The proportion of MSM with inter-provincial transmission clusters were higher than those with intra-provincial transmission clusters, which increased from 0.67% (2/297) during 1996-2008 to 6.36%(30/472) during 2013-2014, showing a significant upward trend (χ(2)=20.276, df=1, P=0.000). The transmission rate in homosexuals of the inter-transmission clusters (86.59%, 71/82) was higher than that of intra-provincial transmission clusters (56.65%, 98/173), and the difference was statistically significant (χ(2)=22.792, P=0.000). The proportion of inter-provincial transmission clusters with more than 2 transmission routes (33.33%, 7/21) was higher than that of intra-provincial clusters (13.11%, 8/61), and the difference was statistically significant (χ(2)=4.273, P=0.039). Results from the transmission network analysis indicated that the proportion of high risk population (degree≥4) with inter-provincial transmission clusters (51.22%, 42/82) was significantly higher than that with intra-provincial transmission clusters (26.59%, 46/173), and the difference was statistically significant (χ(2)=14.932, P=0.000). Inter-provincial clusters were mainly detected in and and MSM. Conclusions: Complex transmission networks were found for HIV-1 CRF01_AE strains in the mainland of China. Inter-provincial transmission clusters increased rapidly, MSM played an important role in the wide spread of the strain. More researches in transmission networks are needed to guide the precision intervention.
China/epidemiology*
;
HIV Infections/virology*
;
HIV-1/isolation & purification*
;
Homosexuality, Male/statistics & numerical data*
;
Humans
;
Male
;
Phylogeny
6.Genetic characteristics of hemagglutinin and neuraminidase of avian influenza A (H7N9) virus in Guizhou province, 2014-2017.
Y H WAN ; L ZHUANG ; Q N ZHENG ; L J REN ; L FU ; W J JIANG ; G P TANG ; D Z ZHANG ; S J LI
Chinese Journal of Epidemiology 2018;39(11):1465-1471
Objective: To understand the molecular characteristics of hemagglutinin (HA) and neuraminidase (NA) as well as the disease risk of influenza virus A H7N9 in Guizhou province. Methods: RNAs were extracted and sequenced from HA and NA genes of H7N9 virus strains obtained from 18 cases of human infection with H7N9 virus and 6 environmental swabs in Guizhou province during 2014-2017. Then the variation and the genetic evolution of the virus were analyzed by using a series of bioinformatics software package. Results: Homology analysis of HA and NA genes revealed that 2 strains detected during 2014-2015 shared 98.8%-99.2% and 99.2% similarities with vaccine strains A/Shanghai/2/2013 and A/Anhui/1/2013 recommended by WHO, respectively. Two strains detected in 2016 and 14 strains detected in 2017 shared 98.2%-99.3% and 97.6%-98.8% similarities with vaccine strain A/Hunan/02650/2016, respectively. Other 6 stains detected in 2017 shared 99.1%-99.4% and 98.9%-99.3% similarities with strain A/Guangdong/17SF003/2016, respectively. Phylogenetic analysis showed that all the strains were directly evolved in the Yangtze River Delta evolution branch, but they were derived from different small branch. PEVPKRKRTAR↓GLF was found in 6 of 24 strains cleavage site sequences of HA protein, indicating the characteristic of highly pathogenic avian influenza virus. Mutations A134V, G186V and Q226L at the receptor binding sites were found in the HA. All the strains had a stalk deletion of 5 amino acid residue "QISNT" in NA protein, and drug resistance mutation R294K occurred in strain A/Guizhou-Danzhai/18980/2017. In addition, potential glycosylation motifs mutations NCS42NCT were found in the NA of 9 of 24 strains. Conclusions: HA and NA genes of avian influenza A (H7N9) virus showed genetic divergence in Guizhou province during 2014-2017. The mutations of key sites might enhance the virulence of the virus, human beings are more susceptible to it. Hence, the risk of infection is increasing.
Animals
;
Base Sequence
;
Birds
;
China/epidemiology*
;
Genome, Viral
;
Hemagglutinin Glycoproteins, Influenza Virus/immunology*
;
Hemagglutinins/genetics*
;
Humans
;
Influenza A Virus, H7N9 Subtype/isolation & purification*
;
Influenza in Birds
;
Influenza, Human/virology*
;
Neuraminidase/genetics*
;
Phylogeny
;
RNA, Viral/genetics*
;
Sequence Analysis, DNA
7.Stratified sampling survey of major human parasitic diseases in Henan province.
B L XU ; H W ZHANG ; Y DENG ; Z L CHEN ; W Q CHEN ; D L LU ; Y L ZHANG ; Y L ZHAO ; X M LIN ; Q HUANG ; C Y YANG ; Y LIU ; R M ZHOU ; P LI ; J S CHEN ; L J HE ; D QIAN
Chinese Journal of Epidemiology 2018;39(3):322-328
Objective: To understand the prevalence of major human parasitic diseases and related factors in Henan province. Methods: This stratified sampling survey was carried out according to the requirement of national survey protocol of major human parasitic diseases, 2014-2015. The prevalence of soil-transmitted helminths infection, taeniasis and intestinal protozoiasis were surveyed in 104 sites selected from 35 counties (districts) and the prevalence of clonorchiasis was surveyed in 62 sites selected from 37 townships. In each survey spot, 250 persons were surveyed. A total of 26 866 persons and 15 893 persons were surveyed. Modified Kato-Katz thick smear was used to detect the eggs of intestinal helminthes. Tube fecal culture was used to identify the species of hookworm. The Enterobius eggs were detected in children aged 3 to 6 years by using adhesive tape. The cyst and trophozoite of intestinal protozoa were examined with physiological saline direct smear method and iodine stain method. Results: The overall infestation rate of intestinal parasites was2.02% in Henan, and the worm infection rate was higher than protozoa infection rate. Fourteen kinds of intestinal parasites were found, including nematode (5 species), trematode (2 species), and protozoan (7 species). The infection rate of Enterobius vermicularis was highest, and Qinba Mountain ecological area had the highest infestation rate of intestinal parasites in 4 ecological areas of Henan. There was no significant difference in intestinal parasite infection rate between males and females (χ(2)=3.630, P=0.057), and the differences in intestinal parasite infection rate among different age groups had significance (χ(2)=124.783, P=0.000 1). The infection rate reached the peak in age group ≤9 years and the major parasite was Enterobius vermicularis. Furthermore the overall human infection rate of parasite showed a downward trend with the increase of educational level of the people (χ(2)=70.969, P=0.000 1), the differences had significance (χ(2)=120.118, P=0.000 1). For different populations, the infection rate of intestinal parasites was highest among preschool children. The infection of intestinal helminth was mainly mild, only 2 severe cases were detected. The infection rate of Clonorchis sinensis in urban residents was only 0.006%. Logistic regression analysis showed that being preschool children (χ(2)=15.765, P=0.000 1) and drinking well water (χ(2)=45.589, P=0.000 1) were the risk factors for intestinal parasite infection, and annual income per capita of farmers was the protective factor against intestinal parasite infection. The infection rates of protozoa and intestinal parasites decreased sharply compared with the results of previous two surveys, and the rate of intestinal helminth infection also dropped sharply compared with the second survey. The numbers of protozoa, helminth and intestinal parasites detected in this survey were all less than the numbers found in the previous two surveys. Conclusions: Compared the results of three surveys in Henan, the infection rate of protozoa and intestinal parasites showed a downward trend. The prevention and treatment of Enterobius vermicularis infection in children should be the key point of parasitic disease control in the future.
Animals
;
Child
;
Child, Preschool
;
Clonorchiasis/epidemiology*
;
Farmers
;
Feces/parasitology*
;
Female
;
Helminthiasis/epidemiology*
;
Helminths
;
Humans
;
Intestinal Diseases, Parasitic/parasitology*
;
Male
;
Prevalence
;
Protective Factors
;
Risk Factors
;
Rural Population
;
Soil Microbiology
;
Surveys and Questionnaires
;
Taeniasis/epidemiology*
;
Trematode Infections/parasitology*
;
Urban Population
;
Water Wells
9.Evaluation of CT diagnostic criteria for peri-pancreatic artery and vein invasion in pancreatic carcinoma.
Hui LI ; Kang-Rong ZHOU ; Da-Yong JIN ; Wen-Hui LOU
Chinese Journal of Oncology 2007;29(2):147-150
UNLABELLEDOBJECTIVE; To evaluate the clinical value of different CT diagnostic criteria for peripancreatic artery and vein invasion in pancreatic carcinoma through comparison with the findings on surgical exploration.
METHODSOf 72 patients of having suspected pancreatic carcinoma were examined by multiplane spiral CT. Among 43 confirmed by surgical pathology; 15 underwent pancreaticoduodenectomy; 28 were found to have unresectable tumors. The peri-pancreatic major vessels including the superior mesenteric artery, celiac artery, hepatic artery, superior mesenteric vein and portal vein were explored carefully during surgical exploration.
RESULTSThe criteria for peri-pancreatic artery invasion was the presence of one of the following signs: artery embeded in tumor, or more than half of the artery circumference involved by tumor with wall irregularity or stenosis. The sensitivity of the above described criteria was 75.0% (12/16). If the criteria of tumor involvement exceeding half of the vessel circumference were adhered to, the sensitivity was 87.5% (14/16), which was high than the former, but the specificity was lower than that of the former one (90.2% versus 95.1%). The criteria for peri-pancreatic vein invasion was presence of any of the following signs: vein obliteration, more than half of the vein circumference involved by tumor, vein wall irregularity, vein stenosis, tear-drop sign of superior mesenteric artery. The sensitivity of the above described criteria was 92.9% (39/42), higher than that of the criteria that more than half of the vessel circumference was involved by the tumor (69.0%, 29/42), but the specificity of both criteria was the same (97.4%, 37/38).
CONCLUSIONFor assessing peri-pancreatic artery and vein invasion, using the combination of different CT diagnostic criteria has higher accuracy than when using only criteria of more than half of vessel circumference involved by tumor.
Adult ; Aged ; Carcinoma, Pancreatic Ductal ; diagnosis ; surgery ; Celiac Artery ; diagnostic imaging ; Female ; Hepatic Artery ; diagnostic imaging ; Humans ; Male ; Mesenteric Artery, Superior ; diagnostic imaging ; Mesenteric Veins ; diagnostic imaging ; Middle Aged ; Neoplasm Invasiveness ; Pancreatic Neoplasms ; diagnosis ; surgery ; Pancreaticoduodenectomy ; Portal Vein ; diagnostic imaging ; Reproducibility of Results ; Sensitivity and Specificity ; Tomography, Spiral Computed ; methods
10.Validation of the Paediatric Hearing Impairment Caregiver Experience (PHICE) Questionnaire.
Lynne H Y LIM ; Ling XIANG ; Naomi L Y WONG ; Kevin C P YUEN ; Ruijie LI
Annals of the Academy of Medicine, Singapore 2014;43(7):362-370
INTRODUCTIONThe paediatric hearing impairment caregiver experience (PHICE) questionnaire is a 68-item instrument that assesses the stress experienced by caregivers of children with hearing impairment (HI). While the questionnaire has been validated in the United States, it may need to be modified for use in the Singapore context due to the differing healthcare system, costing and culture related to caregiving for children with HI. This study aims to modify and validate the PHICE questionnaire to increase its relevance and ease of use in Singapore.
MATERIALS AND METHODSThe original PHICE questionnaire was filled out by 127 caregivers of HI children managed at the otolaryngology clinic of the National University Hospital (NUH). An expert panel was convened to assess the questionnaire for its suitability for use in Singapore. Exploratory factor analysis was conducted to evaluate the underlying factor structure of the original PHICE questionnaire. Items with high cross-loadings were removed and a new factor structure was adopted which was further analysed using confirmatory factor analysis (CFA). Cronbach's alpha (α) was computed to determine the internal consistency of the new subscales.
RESULTSItems that are less relevant in Singapore and those with high cross-loadings were removed. A 5-factor structure with only 42 items remaining and corresponding to the factors: " Policy", "Healthcare", "Education", "Support" and "Adaptation" was adopted. CFA suggests a good model fit for the modified questionnaire, improved from the 8-factor structure of the original PHICE. Cronbach's α were high (>0.7) for each new subscale.
CONCLUSIONThe original PHICE questionnaire has been shortened and reorganised in terms of the subscales composition. The resulting instrument is structurally valid and internally consistent. It is a simple and useful tool for identifying factors related to caregiving that can negatively impact rehabilitation outcomes for children with HI in Singapore. Removal of some sign language items makes this modified version less useful for caregivers, places or countries where sign language is the main focus of rehabilitation for children with HI.
Adolescent ; Caregivers ; Child ; Child, Preschool ; Female ; Hearing Loss ; therapy ; Humans ; Infant ; Infant, Newborn ; Male ; Singapore ; Surveys and Questionnaires