Development of a Rapid Approach for Detecting Sharp Eyespot Resistance in Seedling-Stage Wheat and Its Application in Chinese Wheat Cultivars.

Sharp eyespot, caused by Rhizoctonia cerealis, has become one of the most severe diseases affecting global wheat production in recent decades. Quick and efficient screening methods are required to accelerate the development of cultivars for sharp eyespot resistance in wheat breeding. Here, a two-step colonized wheat kernels (TSCWK) method for the inoculation and classification of sharp eyespot resistance in seedlings was established in a greenhouse. After preliminary verification of the reliability of the method in two replicates, 196 wheat cultivars were assessed for sharp eyespot resistance, and significant correlations were identified among the four replicates (r = 0.78 to 0.84; P < 0.01). Furthermore, the 196 cultivars were scored for sharp eyespot resistance at the milk-ripe stage using traditional toothpick inoculation in the field. Correlation and linear regression analysis showed that the application of this approach at the seedling stage showed good consistency with the traditional field method. Moreover, the scoring of 442 cultivars using the TSCWK method indicated that most cultivars from the Huanghuai valley were susceptible to R. cerealis, suggesting an urgent need to improve sharp eyespot resistance in this region. Additionally, the relative resistance index of sharp eyespot decreased in the surveyed cultivars of the region with time. This study offers a rapid and effective approach for the identification of wheat sharp eyespot resistance and provides valuable germplasm for improving sharp eyespot resistance in wheat breeding.

CYP3A4*1B Polymorphism and Cancer Risk: A Meta-Analysis Based on 55 Case-control Studies.

Published data on the association between CYP3A4*1B polymorphism and cancer risk are inconclusive. To derive a more precise estimation of the association, we conducted a meta-analysis. A systematic search of the PubMed database was performed. A total of 55 separate studies including 22072 cancer cases and 25433 controls were involved in this meta-analysis. We found a significant association between CYP3A4*1B and cancer risk in the overall population in dominant model (AG+GG vs. AA: OR=1.142, 95% CI=1.006-1.295). No significant association was found in recessive model (GG vs. AG+AA: OR=1.156, 95% CI=0.941-1.419), heterozygous model (AG vs. AA: OR=1.109, 95% CI=0.977-1.259), or homozygous model (GG vs. AA: OR=1.213, 95% CI=0.950-1.549). We performed subgroup meta-analysis based on the difference of ethnicity and cancer type. Ethnic subgroup analyses revealed no significant associations of African or Caucasian ethnicities in any genetic models. In the subgroup analysis by Cancer types, we observed an increased risk for leukemia in dominant model and heterozygous model. Excluding studies with controls not in HWE, a significant association was found in dominant model and heterozygous model. In summary, this meta-analysis suggests that the CYP3A4*1B polymorphism might play a modest role in susceptibility to cancer, especially for leukemia.

Persistence of immune responses to vaccine against haemorrhagic fever with renal syndrome in healthy adults aged 16-60 years: results from an open-label2-year follow-up study.

BACKGROUND: Approximately 2 million doses of vaccine against haemorrhagic fever with renal syndrome (HFRS) have been used annually in China. However, there were limited studies focused on persistence of immune responses to HFRS vaccine in healthy adults. A phase 4, multicentre, open trial has been undertaken to assess antibody persistence after HFRS vaccination of healthy adolescents and adults aged 16-60 years. METHODS: The vaccine was administered as a three-dose series at 0, 2 weeks and 6 months, including two primary doses and one booster dose. Anti-hantavirus IgG antibodies were measured by enzyme-linked immunosorbent test (ELISA) pre-vaccination and 1.5, 7 and 24 months after the initial vaccination. RESULTS: A total of 143 individuals aged 16-60 years were included. The median OD (range) values of IgG antibody were 0.005 (0.004-0.016), 0.116 (0.036-0.620), 0.320 (0.065-0.848) and 0.128 (0.011-0.649) pre-vaccination and at 1 month after the two primary doses, 1 month after the booster dose and 18 months after the booster dose. The positivity rate was 7.7%, 40.6%, 62.2% and 48.2%, respectively. CONCLUSIONS: The two primary doses could help healthy individuals to generate an immune response, and this three-dose series may be better than a two-dose regimen.

Long-term persistence of anti-hantavirus antibodies in sera of patients undergoing hemorrhagic fever with renal syndrome and subjects vaccinated against the disease.

Background China has the highest prevalence of hemorrhagic fever with renal syndrome (HFRS) and accounts for 90% of the total cases worldwide. However, the long-term persistence of anti-hantavirus antibodies in sera of patients with HFRS and subjects vaccinated against the disease remains unclear. The aim of the present study was to investigate the prevalence of anti-hantavirus IgG antibodies in sera of patients with prior HFRS, versus subjects vaccinated against the disease and controls in Shaanxi, China. Methods Six hundred individuals were included in this study. We quantified anti-hantavirus IgG antibodies in HFRS patients (n = 100), vaccinees (n = 200), controls from endemic regions (n = 200), and controls from non-endemic regions (n = 100) in China. Results The median optical density (OD) values (range) were 0.803 (0.008-1.813), 0.075 (0.004-1.565), 0.026 (0-1.179), and 0.015 (0.009-0.118) for HFRS patients, vaccinated subjects, endemic controls, and non-endemic controls, respectively. There was a strikingly significant difference between the HFRS group and each non-HFRS group (p < 0.001). The vaccinated subjects were also significantly different from the endemic controls. The time since the acute phase was correlated with the OD values of the HFRS patients. Conclusions Our study suggests that HFRS patients gain long-lasting protection and that vaccination may be an effective way to stimulate antibody production.

Changes in rodent abundance and weather conditions potentially drive hemorrhagic fever with renal syndrome outbreaks in Xi'an, China, 2005-2012.

BACKGROUND: Increased risks for hemorrhagic fever with renal syndrome (HFRS) caused by Hantaan virus have been observed since 2005, in Xi'an, China. Despite increased vigilance and preparedness, HFRS outbreaks in 2010, 2011, and 2012 were larger than ever, with a total of 3,938 confirmed HFRS cases and 88 deaths in 2010 and 2011. METHODS AND FINDINGS: Data on HFRS cases and weather were collected monthly from 2005 to 2012, along with active rodent monitoring. Wavelet analyses were performed to assess the temporal relationship between HFRS incidence, rodent density and climatic factors over the study period. Results showed that HFRS cases correlated to rodent density, rainfall, and temperature with 2, 3 and 4-month lags, respectively. Using a Bayesian time-series Poisson adjusted model, we fitted the HFRS outbreaks among humans for risk assessment in Xi'an. The best models included seasonality, autocorrelation, rodent density 2 months previously, and rainfall 2 to 3 months previously. Our models well reflected the epidemic characteristics by one step ahead prediction, out-of-sample. CONCLUSIONS: In addition to a strong seasonal pattern, HFRS incidence was correlated with rodent density and rainfall, indicating that they potentially drive the HFRS outbreaks. Future work should aim to determine the mechanism underlying the seasonal pattern and autocorrelation. However, this model can be useful in risk management to provide early warning of potential outbreaks of this disease.

The first human infection with severe fever with thrombocytopenia syndrome virus in Shaanxi Province, China.

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease discovered in China in 2009. In July 2013, the first human infection with SFTS virus (SFTSV) was detected in Shaanxi Province, Western China. METHODS: A seroprevalence study among humans was carried out in an SFTS endemic village; specifically, serum samples were collected from 363 farmers in an SFTS endemic village in Shaanxi Province. The presence of SFTSV antibodies in serum was determined using an ELISA. RESULTS: SFTSV antibodies were found in a total of 20 people (5.51%), with no significant difference between males and females (6.93% and 4.42%, respectively; Chi-square=1.29, p=0.25). Moreover, the SFTSV antibody positive rate was not significantly different across different age groups (Chi-square=2.23, p=0.69). CONCLUSIONS: SFTSV readily infects humans with outdoor exposure. The results of the serological study indicate that the virus circulates widely in Shaanxi Province. SFTSV represents a public health threat in China.

[Comparison of direct immune-fluorescent assay and real-time quantitative PCR in detecting the Hantavirus].

OBJECTIVE: To compare the differences between the direct immuno-fluorescent assay (DFA) and real-time quantitative PCR in detecting the Hantavirus (HV) in rat lungs. METHODS: From April to October in 2012, a total of 479 rats were caught by mouse-trap in residential or wild areas in Huxian, Jingyang, and Meixian of Shaanxi province, where haemorrhagic fever with renal syndrome (HFRS) was highly prevalent. The rats were dissected to take the two lungs, one was frozen and applied immuno-fluorescent assay to detect HV antigen while the other one was extracted its RNA and detected HV nucleic acid by real-time quantitative PCR. Then we compared the positive rate of the two methods. RESULTS: Out of the 479 rats, 105 were caught from residential areas and the other 374 were caught from wild areas. Among the 105 rats caught from residential areas, no HV were detected out neither by DFA nor by real-time quantitative PCR. Among the 374 wild rats, 13.1% (49/374) were detected HV positive by DFA and 14.7% (55/374) were detected HV positive by real-time quantitative PCR. The difference showed no statistical significance (χ(2) = 0.402, P = 0.526). When detecting each lung sample, the HV positive rate was 10.2% (49/479) under the detection by DFA while the HV positive rate was 11.5% (55/479) under the detection by real-time quantitative PCR. The difference had no statistical significance (χ(2) = 1.286, P = 0.257) and the consistency coefficient was 68.2% under the paired chi-square test analysis, which showed high consistency (u = 11.759, P < 0.05). The sensitivity of real-time quantitative PCR to detect HV was 77.6% (38/49) comparing with DFA as standard, and the specificity was 96.1% (413/430). Out of the 9 suspected HV positive sample detected by DFA, 6 were confirmed positive by real-time quantitative PCR and 3 were denied. CONCLUSION: Compared with the DFA, real-time quantitative PCR could also be used to detect the infection of HV in rats, and the result might be more stable.

[Analysis the viral etiology of fever and respiratory tract infection syndrome in Shaanxi province].

OBJECTIVE: Analysis the viral pathogenic spectrum for patients with fever and respiratory tract infection syndrome in Shaanxi province during 2010 and investigate the molecular epidemiology characteristics of respiratory syncytial virus. METHODS: A total of 208 patients' pharyngeal swabs were collected based on surveillance definition from January 2010 to January 2011 and screened for sixteen human respiratory virus types/subtypes by Qiaxcel-based multiplex reverse transcription-PCR assay, including HRV,HCoV, Flu, HPIV, ADV, HRSV, HMPV and HBoV and investigate molecular epidemiology of HRSV by sequencing and phylogenetic analysis of the C-terminal second hypervariable region of the G gene. RESULTS: 109 out of 208 specimens (53%) were positive for one or more viruses. HRSV(42. 2%) was the dominant pathogen detected, followed by Flu(24. 5%), PIV(20%), HRV(13.6%) and ADV( 10.9%),there were also 8 strains of HCoV, 5 strains of HMPV and 3 strains of HBoV detected. The results showed that 22 specimens were positive for two or more viruses, PIV (14/22) was the most frequently detected viral agent among co-infection specimens, and the highest incidence of mixed infection is aged 15-39 years group (P < 0.05). The overall viral detection rate was no related to age. In addition to Flu, HMPV and PIV, other viruses (HRV, HBoV, HCoV, ADV, RSV) mainly infected 0 to 4 years old children. Among 46 HRSV positive specimens, 42 HRSV-A strains clustered into NA1 genotype and two HRSV-B strains clustered into two genotypes, BA9 and GB2. CONCLUSION: HRSV is the dominate pathogen collected from patients with fever and respiratory tract infection syndrome in Shaanxi and HRSV A is the predominant subtype. For most viruses, infection was most prevalent among children aged <4 years. PIV was the most common pathogen in co-infection.

[Genetic characterization of human parainfluenza virus 3 circulating in Gansu and Shaanxi Provinces from 2009 to 2011].

To investigate the genetic characterization of Human parainfluenza virus-3 (HPIV-3) circulating in Gansu and Shaanxi Provinces of China, 719 throat swabs were collected from pediatric patients with acute respiratory infections from 2009-2011. Multiplex RT-PCR was used to screen common respiratory viral pathogens. For HPIV-3-positive specimens, nested RT-PCR was used to amplify the HN gene of HPIV-3. The nucleotides of Hemagglutinin-neuraminidase(HN)gene of 13 HPIV-3 positive strains identified in Gansu and Shaanxi Provinces were successfully sequenced and compared with those downloaded from GenBank. The phylogenetic analysis based on the nucleotides sequence of HN gene showed that 13 HPIV-3 strains belonged to sub-cluster C3 with little sequence variation (overall nucleotide divergence of 0.2%-2.3% and amino acid divergence at 0-1.1%). Compared with the complete gene of HPIV-3 strains from U.S.A., Canada, and Australia, the biggest divergence of the nucleotide and amino acid lovels was 6.0% and 3.4%, respectively. The nucleotide divergence between shaanxi09-2 and shaanxi10-H0091 was 0.9%, while the nucleotide divergence between shaanxi10-H005 and gansull-62110372 was 0.5%, between shaanxi09-2 and BJ/291/09 was 0.6%. However, there was no amino acid divergence among them. It is likely that HPIV-3 virus had been transmitting in Gansu and Shaanxi Provinces for several years. Human parainfluenza virus-3 (HPIV-3) circulated in Gansu and Shaanxi Provinces from 2009 to 2011 belonged to sub-cluster C3.

[Long term epidemiological effects of vaccination on hemorrhagical fever with renal syndrome (HFRS) in Shaanxi provincial HFRS epidemic areas].

OBJECTIVE: To evaluate the protective rate and the variation of HFRS-IgG on hemorrhagical fever with renal syndrome (HFRS) vaccine. METHODS: Cluster, random sampling and cross-sectional study were used to assess the protective rate of HFRS vaccination. Level of HFRS-IgG was detected with ELISA in epidemic and non-epidemic areas of HFRS. RESULTS: Curve equation was obtained as Yprotective rate=(0.863+0.283/Xvaccination term)×100% by protective rate with vaccination term. Protective rates showed a reducing trend, 90% after 7-8 years of vaccination, 88% after 10 years, and 94% on average. Absorbance (A) value of HFRS-IgG was 4 times higher in persons with vaccination than those without, in the epidemic area. Higher antibody level could be obtained after primary vaccination, but the level of antibody had a 50% reduction after 5-10 years of vaccination, and a 60% reduction after 10 years of vaccination. CONCLUSION: HFRS antibody had a 50% reduction after 5-10 years of vaccination. The protective rate of HFRS vaccination had a 90% loss, after 7-8 years of vaccination. Booster dose was necessary after 7 years of vaccination.

CYP1A1 Ile462Val polymorphism and susceptibility to lung cancer: a meta-analysis based on 32 studies.

Lung cancer is the second most common human malignant disease and the leading cause of cancer-related mortality worldwide. The effect of CYP1A1 IleVal polymorphism on susceptibility to lung cancer has been researched extensively over the last two decades. However, controversial results were obtained. To provide a more robust estimate of the effect, a meta-analysis was carried out. We systematically searched the PubMed database for studies published before August 2010, without language restriction. On the basis of our search criteria, a total of 32 studies (5126 patients and 6974 controls) were included in the meta-analysis. Overall, CYP1A1 IleVal polymorphism is associated with lung cancer risk (GG vs. AG+AA: odds ratio=1.61, 95% confidence interval: 1.19-2.17; GG vs. AA: odds ratio=1.70, 95% confidence interval: 1.23-2.35). Ethnic subgroup analyses showed that a significant association was found in Asians, but not in Africans, Caucasians, or other populations. In subgroup analyses by histology, the result is not reliable. In conclusion, this meta-analysis suggests that the CYP1A1 IleVal polymorphism might play a modest role in susceptibility to lung cancer, especially in Asians.

TP53 codon 72 polymorphism and colorectal cancer susceptibility: a meta-analysis.

Colorectal cancer constitutes a significant proportion of the global burden of cancer morbidity and mortality. A number of studies have been conducted to explore whether TP53 codon 72 polymorphism is associated with colorectal cancer susceptibility. However, controversial results were obtained. In order to derive a more precise estimation of the relationship, we systematically searched Medline, Google scholar, and Ovid database for studies reported before May 2010. A total of 3603 colorectal cancer cases and 5524 controls were included. TP53 codon 72 polymorphism was not associated with colorectal cancer risk in all genetic models (for dominant model: OR = 0.99, 95% CI: 0.86-1.15; for recessive model: OR = 1.00, 95% CI: 0.81-1.23; for Arg/Pro vs. Arg/Arg: OR = 1.00, 95% CI: 0.87-1.15; for Pro/Pro vs. Arg/Arg: OR = 0.97, 95% CI: 0.76-1.25). In the subgroup analyses by ethnic groups and sources of controls, no significant associations were found in all models. Taken together, this meta-analysis suggested that the biologically usefulness of TP53 codon 72 polymorphism as a selection marker in colorectal cancer susceptibility may be very limited.

Prokaryotic expression, purification and activity assay of recombinant vascular endothelial growth factor.

OBJECTIVE: To express human vascular endothelial growth factor (hVEGF(165)) in E. coli JM109 in the form of fusion protein by genetic engineering and test the biological activity and immunological competence of the expressed protein. METHODS: hVEGF(165) gene was subcloned by PCR and inserted into pQE30 plasmid. hVEGF(165) fusion protein was expressed in E. coli JM109 and purified by Ni(2+)-NTA. The immunological competence of the expressed protein was tested by means of Western blotting and enzyme-linked immunosorbent assay (ELISA), and its biological activity was assayed by chicken chorioallantoic membrane (CAM) and Matrigel angiogenesis assay. RESULTS: The recombinant hVEGF(165) fusion protein was successfully expressed in E. coli JM109 and its expression accounted for 30% of the total cellular protein. The purified protein presented a single band of 23 kD in SDS-PAGE. Western blotting, ELISA, CAM and matrigel angiogenesis assay showed excellent immunologic competence and biological activity of the recombinant protein. CONCLUSION: Recombinant hVEGF(165) protein with excellent biological activity has been successfully expressed in E.coli JM109, which may facilitate future study in construction of prefabricated tissue-engineered bone graft.