Confirmed cases of avian influenza A(H7N9) virus infection in humans continue to occur in mainland China. Few confirmed cases have occurred in poultry workers despite potentially higher rates of exposure.
In order to investigate the lesions and proteins with differential expression in cells infected with the 2009 A (H1N1) virus and to determine the specific proteins involved in cell damage, the present study has been performed. BEAS-2B cells were infected with the 2009 A (H1N1) influenza virus or the seasonal H1N1 influenza virus for 12, 24, 48, and 72 h, and cell cycle and apoptosis were analyzed with flow cytometry. Total cellular proteins were extracted and underwent two-dimensional gel electrophoresis. The differentially expressed proteins underwent mass spectrometry for identification. The results showed that after 12 h, cells infected with the virus strain sourced from severe cases had the highest apoptosis rate (P?0.05). After 48 h, cells infected with the virus strain sourced from fatal cases and severe cases had the highest apoptosis rate (P?0.05), and after 72 h, cells infected with virus strains from fatal cases and ordinary cases had the highest apoptosis rate (P?0.05). All the four influenza virus strains induced cell cycle arrest mainly at the G0/G1 phase. Eighteen differentially expressed proteins were identified, including galectin-1, cofilin-1, protein DJ-1, proteasome subunit ? type-5, macrophage migration inhibitory factor, translationally controlled tumor protein, profilin 1, and interferon ?-2. Galectin-1 was specifically observed in BEAS-2B infected with 2009 A (H1N1) influenza viruses, and cofilin-1 was specifically observed in BEAS-2B cells in the late stage of 2009 A (H1N1) influenza virus infection. In conclusion, differential effects of the 2009 A (H1N1) influenza virus and seasonal H1N1 influenza virus were identified on the cell cycle and apoptosis, and galectin-1 may play a role in cell apoptosis induced by 2009 A (H1N1) influenza virus.
To explore the correlation of human chorionic gonadotrophin (hCG) level in the follicular fluid on oocyte retrieval day with the number of oocytes retrieved, maturation rate, embryonic development, and pregnancy outcome in controlled ovarian stimulation cycles.
Hand, foot, and mouth disease (HFMD) affects more than one million children, is responsible for several hundred child deaths every year in China and is the cause of widespread concerns in society. Only a small fraction of HFMD cases will develop further into severe HFMD with neurologic complications. A timely and accurate diagnosis of severe HFMD is essential for assessing the risk of progression and planning the appropriate treatment. Human serum can reflect the physiological or pathological states, which is expected to be an excellent source of disease-specific biomarkers. In the present study, a comparative serological proteome analysis between severe HFMD patients and healthy controls was performed via a two-dimensional difference gel electrophoresis (2D-DIGE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) strategy. Fifteen proteins were identified as differentially expressed in the sera of the severe HFMD patients compared with the controls. The identified proteins were classified into different groups according to their molecular functions, biological processes, protein classes and physiological pathways by bioinformatics analysis. The up-regulations of two identified proteins, serum amyloid A (SAA) and clusterin (CLU), were confirmed in the sera of the HFMD patients by ELISA assay. This study not only increases our background knowledge about and scientific insight into the mechanisms of HFMD, but also reveals novel potential biomarkers for the clinical diagnosis of severe HFMD.
The drivers of influenza seasonality remain heavily debated, especially in tropical/subtropical regions where influenza activity can peak in winter, during the rainy season, or remain constant throughout the year. We compared the epidemiological and evolutionary patterns of seasonal influenza epidemics in Hong Kong and Shenzhen, two adjacent cities in subtropical southern China. This comparison represents a unique natural experiment as connectivity between these two cities has increased over the past decade. We found that while summer influenza epidemics in Shenzhen used to peak 1-3 months later than those in Hong Kong, the difference decreased after 2005 (p<0.0001). Phylogenetic analysis revealed that influenza isolates from Shenzhen have become genetically closer to those circulating in Hong Kong over time (p=0.045). Further, although Shenzhen isolates used to be more distant from the global putative source of influenza viruses than isolates from Hong Kong (p<0.001), this difference has narrowed (p=0.02). Overall, our study reveals that the influenza activities show remarkably distinct epidemiological and evolutionary patterns in adjacent subtropical cities and suggests that human mobility patterns can play a major role on influenza dynamics in the Subtropics.
Genome-wide association studies (GWAS) of ischemic stroke (IS) have been performed on several cohorts of Caucasian or African population and Japanese, resulting in somewhat inconsistent conclusion. We aimed to identify susceptibility loci for IS by exome sequencing in a Chinese Han population. Exome sequencing was used to screen susceptibility loci among 100 cases and 100 matched controls. Significant SNPs from the first stage were verified in up to 3,554 participants from three hospital-based case-control studies. In the initial exome sequencing analysis, rs10489177 in c1orf156 gene located on chromosome 1q24 (p?1?×?10(-8)) and rs17118 in XYLB gene located on chromosome 3p21 (p?1?×?10(-6)) were found to be significantly associated with IS. In the following validation stage, significantly increased odds ratios were observed in individuals with rs10489177 GG (OR?=?2.02, 95 % CI?=?1.35-3.03) or rs17118 AA genotype (OR?=?1.50, 95 % CI?=?1.17-1.91). The rs10489177 GG genotype was associated with significantly increased risk for IS in individuals without hypertension (OR?=?2.78, 95 % CI?=?1.59-4.86) and in individuals without diabetes (OR?=?1.93, 95 % CI?=?1.27-2.94). In contrast, the rs17118 AA genotype may significantly increase the risk for IS, particularly for individuals with hypertension (OR?=?1.73, 95 % CI?=?1.08-2.78) and for individuals without diabetes (OR?=?1.52, 95 % CI?=?1.17-1.98) or non-smoker (OR?=?1.59, 95 % CI?=?1.16-2.19). Collectively, our study identified two novel loci (rs17118 and rs10489177) which were associated with an increased risk for IS in Chinese Han populations. Further studies are needed to confirm these associations in other populations and elucidate the biological mechanisms underlying the observed associations.
Myxovirus resistance A (MxA) is an antiviral protein induced by type I interferons ? and ? (IFN-? and IFN-?) that can inhibit virus replication. We examined whether the MxA polymorphisms were related to the risk and severity of enterovirus 71 (EV71) infection in Chinese populations. The MxA C-123A and G-88T polymorphisms were genotyped in two independent case-control populations in China by polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) analysis. Multivariate logistic regression analysis was used to calculate adjusted odds ratios (ORs) and 95 % confidence intervals (95 % CIs). MxA messenger RNA was quantified by real-time quantitative PCR in peripheral blood mononuclear cells (PBMCs) from 45 healthy children and 19 patients with EV71 infection. Significantly decreased susceptibility to EV71 infection was observed for the -123A allele and -88T allele carriers, with ORs (95 % CIs) estimated as 0.56 (0.39-0.81) and 0.64 (0.47-0.88), respectively, in the northern population. This association was confirmed in the southern population, with ORs (95 % CIs) estimated as 0.58 (0.38-0.89) and 0.67(0.47-0.95), respectively. The A- 123T- 88 haplotype was also significantly associated with lower risk of EV71 infection in both the northern (OR = 0.62; 95 % CI = 0.44-0.85) and the southern population (OR = 0.63; 95 % CI = 0.43-0.92). Furthermore, we observed higher MxA messenger RNA levels in IFN?1a-stimulated PBMCs from the -123A or -88T allele carriers compared with that from nocarriers. Our findings suggest that polymorphisms in the MxA promoter may play a role in mediating the susceptibility to EV71 infection in Chinese population.
On December 29, 2011, a man infected with a subclade of the H5N1 virus was confirmed in Shenzhen, China. The clinical symptoms and immune factors of the patient were investigated and the phylogenetic and molecular characteristics of the virus were analyzed. High fever, rapid development of serious pneumonia and multi-organ failure were the main clinical symptoms. Arterial blood gas analysis showed that PaCO2 rose sharply and PO2 decreased. Leukocyte and platelet counts decreased rapidly. Peripheral blood lymphocyte counts indicated lymphopenia and inverted ratios of CD4(+) to CD8(+) cells. Cytokine analysis showed that the levels of serum IL-6, IL-10, and IFN-r continued to increase, whereas the levels of IL-12 and TNFs decreased during the clinical course. MCP-1 and IP-10 remained at a high level after infection. Phylogenetic analysis confirmed that the virus A/Shenzhen/1/2011 belongs to the new subclade 184.108.40.206. An Arg (R) insertion at P6 and an RP8I substitution in the HA cleavage site motif were detected in the virus. Compared to the vaccine strain, 16 specific substitutions occurred in the HA1 protein. Some of them were located on the receptor-binding site, glycosylation site and the region of the antigenic determinant. In summary, serious complications and immune system disorders were the main features of the infection with H5N1. Gene variation did not weaken the highly pathogenic features of viruses and the pathogenicity and antigenicity of the new subclade virus were changed.
Genome-wide single nucleotide polymorphism (SNP) association studies recently identified two SNPs (rs11833579 and rs12425791) on chromosome 12p13 that are associated with ischemic stroke (IS) in Caucasian or Black persons from America and the Netherlands. Our aim was to determine whether these SNPs were associated with IS in Chinese Han population.
Type B influenza virus is one of the major epidemic strains and responsible for considerable mortality and morbidity. Rapidly and accurately identifying different influenza B virus lineages, i.e., B/Yamagata (B/Y) and B/Victoria (B/V), is desirable during the flu season. However, the available rapid techniques lack sensitivity, and the usual methods for identifying influenza viruses require expansion of virus in tissue culture or embryonated hens eggs. Thus, we developed several sets of primer pairs that were able to detect and distinguish B/Y and B/V in a single real-time PCR assay. Used in conjunction with two sets of specific primers that exhibited purine at 3 end of at least one primer targeting on HA gene of B/Y and B/V lineages allows us to accurately identify approximately 10(2) copies per microliter for B/Y and B/V with intra- and inter-assay coefficient of variation (CV) <4%. When it was used to test 17,765 throat swab specimens obtained in the 2006-2010 influenza surveillance season, this method was comparable to hemagglutination inhibition assay in detection, typing and subtyping of influenza viruses with 100% true-negative (specificity) and 100% true-positive (sensitivity). Taken together, this method provides sensitive and robust tool for routine diagnosis and on-time epidemiological examination for WHO decisions on vaccine composition.
Use of multiplex real-time reverse transcription polymerase chain reaction (RT-PCR) for the simultaneous detection of influenza type B virus and influenza A virus subtypes H5N1, H3N2, and H1N1 has been described. The method exhibited a high specificity and sensitivity of approximately 10(1)-10(2) copies per microliter or 10(-3)-10(-2) TCID50/L for each subtype, as well as a high reproducibility with coefficient of variation (CV) ranging from 0.27% to 4.20%. The assays can be performed commendably on various models of real-time PCR instruments; including ABI7500, ROCH 2.0, and Mx3005p. In an analysis of 436 clinical samples from patients during the year 2009, this detection method has successfully identified 261 positive samples, as compared to only 189 positive samples using the conventional cell culture systems, and at the same time further differentiated them as 35 type B, 21 subtype H1N1, and 205 subtype H3N2. The results indicate that the multiplex real-time RT-PCR method is a potential tool for rapid screening of influenza virus from a large pool of clinical samples during flu pandemics and facilitates early influenza virus identification in most public health laboratories around the world.
Increasing evidences for the role of tumor necrosis factor-alpha (TNF-alpha) in the occurrence of ischemic stroke (IS) have shown that it belongs to pro-inflammatory cytokines and carries functional polymorphisms (TNF-alpha -238G/A and TNF-alpha -308G/A) in its promoter region, which affect their transcription rate and plasma cytokine level. We determined the association between these polymorphisms and the occurrence of IS in the Chinese Han and Uyghur populations.
Polymorphisms of G-572C and G-174C in the interleukin-6 (IL-6) promoter can affect both the transcription and secretion of IL-6 and may be involved in inflammation related to and the pathogenesis of ischemic stroke (IS). However, whether IL-6 polymorphisms are indeed risk factors for IS remains controversial. We recruited 748 Chinese IS patients diagnosed by magnetic resonance imaging (MRI) within 24h of symptom onset and 748 normal healthy controls from two ethnic populations and performed two case-control studies in order to assess the nature of the polymorphisms of IL-6 and any links with IS. Common polymorphic loci in the IL-6 gene promoter were determined by TaqMan SNP genotyping assays. Multivariate logistic regression analysis was used to examine the association between IL-6 genotypes and a diagnosis of IS. We found that the C allele frequency at the -174 promoter region of IL-6 was extremely low in both IS patients and controls in both ethnic groups. The G allele of the promoter single nucleotide polymorphism (SNP) G-572C was more common in IS subjects than controls (P=0.004, corrected for multiple testing) in the Han population but not in the Uyghur population. GC carriage therefore increased the risk of IS in the Han ethnic group (OR 1.45, 95% CI 1.13-1.86). In addition, the differences in GG and GC frequency between the two ethnic populations were significant. The C allele frequency at the -174 promoter region of IL-6 was rare in Chinese IS patients and controls from either ethnic group. We conclude that IL-6-572GC may be an independent risk factor for IS in the Chinese Han population.
There is evidence in experimental animals for the urolithiasis and carcinogenicity of melamine, but no evidence for melamine in humans. To evaluate any association between melamine-contaminated powdered formula (MCPF) feeding and urolithiasis, and further the MCPF feeding and oxidative damage to DNA in infants. A cross-sectional study was carried out to assess urolithiasis and urinary 8-hydroxy-2-deoxyguanosine (8-OHdG) in four groups of infants according to the type of feeding: (1) Infants receiving over 90% of their intake as MCPF. (2) Infants receiving 50-90% of their intake as MCPF. (3) Infants receiving less than 50% of their intake as MCPF. (4) Infants receiving over 90% of their intake as imported milk powdered formula free of melamine contamination. Groups 1 to 3 are the observation groups, and Group 4 is the reference group. There is a significant correlation between urolithiasis and percentage of MCPF intake. The mean urinary 8-OHdG concentrations for Groups 1, 2, 3, and 4 were: 2.03 +/- 0.52, 1.67 +/- 0.28, 1.90 +/- 0.39, and 1.85 +/- 0.47 micromoles per mole of creatinine, respectively. There were no significant differences in the mean urinary 8-OHdG concentrations among the observation and control groups. There were also no correlation between mean urinary 8-OHdG excretions and percentage of MCPF intake. Our data suggested that melamine exposure were associated with urolithiasis, but it might not cause any increase in oxidative damage of DNA in infants.
Previous investigations have indicated that cooks are exposed to polycyclic aromatic hydrocarbons (PAHs) from cooking-oil fumes. However, Emission of PAH and their carcinogenic potencies from cooking oil fumes sources have not been investigated among cooks. To investigate the urinary excretion of a marker for oxidative DNA damage, 8-hydroxydeoxyguanosine (8-OHdG), in different groups of cooks and different exposure groups, and to study the association between 8-OHdG and 1-hydroxypyrene(1-OHP), a biological marker for PAH exposure. Urine samples were collected from different groups of cooks (n = 86) and from unexposed controls (n = 36); all were male with similar age and smoking habits. The health status, occupational history, smoking, and alcohol consumption 24 h prior to sampling was estimated from questionnaires. The urine samples were frozen for later analyses of 8-OHdG and 1-OHP levels by high-performance liquid chromatography. Excretion in urine of 8-OHdG was similar for controls (mean 1.2micromol/mol creatinine, n = 36), and for those who had been in the kitchen with an exhaust-hood operating (mean 1.5micromol/mol creatinine, n = 45). Cooks exposed to cooking-oil fumes without exhaust-hood operation had significantly increased excretion of 8-OHdG (mean 2.3micromol/mol creatinine, n = 18), compared with controls. The urinary levels of ln 1-OHP and ln 8-OHdG were still significantly correlated in a multiple regression analysis. The results indicate that exposure to PAH or possibly other compounds in cooking-oil fumes may cause oxidative DNA damage.
In the past 3 years, the 2009 pandemic influenza virus H1N1 (pH1N1) has led to many severe or fatal cases. The virus-related factors that cause severe or fatal disease are not clear. The clinical and molecular characteristics of pH1N1 infections with severe or fatal disease were examined to understand the correlation between pH1N1 infection and disease severity. Since 2009, three pH1N1 influenza epidemic outbreaks have occurred in Shenzhen, China. One hundred forty-six severe cases were confirmed in the first wave in 2009. In severe cases, a high proportion (49.3%) of patents displayed high fever (>39.0°C), and 73.2% of patients had pneumonia and tracheobronchitis. Seven fatal cases were recorded: three with viral encephalitis and four with respiratory failure. The results of sequencing and phylogenetic analysis showed that the viruses from fatal or severe cases were scattered throughout the phylogenetic tree. Four substitutions (D222G, D222N, D222E, and Q223R) were observed on the 220-loop of the receptor-binding sites of the HA gene. Both D222G and D222N were associated statistically with severe disease. The 2011 viruses had evolved into two distinct branches. Ten specific point mutations occurred in the 2011 virus. In summary, high fever, lower respiratory tract infections and serious complications were the main features of severe cases. Gene variation seemed not to be the main reason for severe disease. Vaccination is the effective mean to prevent infection and severe disease.
To develop a method to rapidly detect the N1 and N2 subtype of influenza virus by fluorescence real-time quantitative PCR.
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