Characterization and pathogenicity of the porcine epidemic diarrhea virus isolated in China.

Piglet diarrhea caused by the porcine epidemic diarrhea virus (PEDV) is a common problem on pig farms in China associated with high morbidity and mortality rates. In this study, three PEDV isolates were successfully detected after the fourth blind passage in Vero cells. The samples were obtained from infected piglet farms in Jilin (Changchun), and Shandong (Qingdao) Provinces of China and were designated as CH/CC-1/2018, CH/CC-2/2018, and CH/QD/2018. According to the analysis of the complete S protein gene sequence, the CH/CC-1/2018 and CH/CC-2/2018 were allocated to the G2b branch, while CH/QD/2018 was located in the G1a interval and was closer to the vaccine strain CV777. Successful detection and identification of the isolated strains were carried out using electron microscopy and indirect immunofluorescence. Meanwhile, animal challenge experiments and viral RNA copies determination were used to compare the pathogenicity. The results showed that CH/CC-1/2018 in Changchun was more pathogenic than CH/QD/2018 in Qingdao. In conclusion, the discovery of these new strains is conducive to the development of vaccines to prevent the pandemic of PEDV, especially that the CH/CC-1/2018, and CH/CC-2/2018 were not related to the classical vaccine strain CV777.

Mass spectrometry imaging technology in metabolomics: A systematic review.

Mass spectrometry imaging (MSI) is a powerful label-free analysis technique that can provide simultaneous spatial distribution of multiple compounds in a single experiment. By combining the sensitive and rapid screening of high-throughput MS with spatial chemical information, metabolite analysis and morphological characteristics are presented in a single image. MSI can be used for qualitative and quantitative analysis of metabolic profiles and it can provide visual analysis of spatial distribution information of complex biological and microbial systems. Matrix-assisted laser desorption ionization, laser ablation electrospray ionization and desorption electrospray ionization are commonly used in MSI. Here, we summarize and compare these three technologies, as well as the applications and prospects of MSI in metabolomics.

Gas chromatography/mass spectrometry analysis of organic acid profiles in human serum: A protocol of direct ultrasound-assisted derivatization.

RATIONALE: Low-molecular-weight organic acids that generally contain one to three carboxyl groups are involved in many important biological processes; therefore, it is important to develop a quantitative method for analyzing organic acids in serum in order to allow an evaluation of metabolic changes. In this study, we evaluated a protocol for detecting 26 organic acids in serum based on ultrasound-assisted derivatization by gas chromatography/mass spectrometry (GC/MS). METHODS: Serum samples were prepared using ultrasound-assisted silane derivatization before GC/MS analysis to quantify concentrations of organic acids. Additionally, we investigated the variables affecting derivatization yields, including the extraction solvent, derivatization reagents, and derivatization conditions (reaction temperature, duration, and sonication parameters). The protocol was ultimately applied to detect organic acid profiles related to obesity. RESULTS: We used acetone as the extraction solvent and determined suitable derivatization conditions, as follows: BSTFA + 1% TMCS, 50°C, 10 min, and 100% ultrasound power. The protocol showed satisfactory linearity (r = 0.9958-0.9996), a low limit of detection (0.04-0.42 µmol/L), good reproducibility (coefficient of variation (CV) %: 0.32-13.76%), acceptable accuracy (recovery: 82.97-114.96%), and good stability within 5 days (CV%: 1.35-12.01% at room temperature, 1.24-14.09% at 4°C, and 1.01-11.67% at -20°C). Moreover, the protocol was successfully applied to obtain the organic acid profiles from obese and healthy control subjects. CONCLUSIONS: We identified and validated a protocol for ultrasound-assisted derivatization prior to GC/MS analysis for detecting 26 kinds of organic acids in serum. The results suggest the efficacy of this protocol for clinical applications to determine metabolic changes related to fluctuations in organic acid profiles.

Analysis of Combined Indicators for Risk of Osteoporotic Hip Fracture in Elderly Women.

OBJECTIVE: To compare the accuracy of combined independent risk factors in assessing the risk of hip fractures in elderly women. METHODS: Ninety elderly females who sustained hip fractures (including femoral neck fractures and intertrochanteric fractures) and 110 female outpatients without a hip fracture were included in our cross-sectional study from 24 November 2017 to 20 May 2019. The age of subjects in the present study was ≥65 years, with the mean age of 78.73 ± 7.77 and 78.09 ± 5.03 years for women with and without elderly hip fractures, respectively. Bone mineral density (BMD), Beta-carboxy terminal telopeptide (ß-CTX), N-terminal/mid region (N-MID), and 25(OH)D levels were analyzed. A novel evaluation model was established to evaluate combined indicators in assessing hip fractures in elderly women. RESULTS: Compared with the control group, taller height (155.68 ± 6.40 vs 150.97 ± 6.23, P < 0.01), higher levels of ß-CTX (525.91 ± 307.38 vs 330.94 ± 289.71, P < 0.01), and lower levels of total hip BMD (0.662 ± 0.117 vs 0.699 ± 0.111, P = 0.022), femoral neck BMD (0.598 ± 0.106 vs 0.637 ± 0.100, P = 0.009), and 25(OH)D (15.67 ± 7.23 vs 29.53 ± 10.57, P < 0.01) were found in the facture group. After adjustment for confounding factors, logistic regression analysis revealed that 25(OH)D (adjusted OR 0.837 [95% CI 0.790-0.886]; P < 0.01), femoral neck BMD (adjusted OR 0.009 [95% CI 0.000-0.969]; P = 0.048) and height (adjusted OR 1.207 [95% CI 1.116-1.306]; P < 0.01) remained risk factors for hip fractures in elderly women. Then a model including independent risk factors was established. A DeLong test showed the area under the receiver operator characteristic (ROC) (Area under the curve [AUC]) of 25(OH)D was significantly greater than that for femoral neck BMD (P < 0.01) and height (P < 0.01). The AUC of model including 25(OH)D and height was significantly greater than that of other combinations (P < 0.01). CONCLUSION: 25(OH)D, femoral neck BMD and height were associated with the occurrence of hip fractures in elderly women even after adjustment for confounding factors, and a model including 25(OH)D and height could provide better associated power than other combinations in the assessment of elderly hip fractures.

Lactobacillus plantarum surface-displayed influenza antigens (NP-M2) with FliC flagellin stimulate generally protective immune responses against H9N2 influenza subtypes in chickens.

The H9N2 avian influenza virus (AIV) causes serious economic losses to the poultry industry every year. Vaccines that induce a mucosal immune response may be successful against influenza virus infection because its transmission occurs primarily in the mucosa. To develop novel and potent oral vaccines based on Lactobacillus plantarum (L. plantarum) to control the spread of AIV in poultry industry, in the present study, we constructed and expressed fusions of the influenza antigens NP and M2 with the Salmonella Typhimurium flagellinprotein FliC on the surface of L. plantarum. Oral immunization of chicks was performed, and serum antibodies, mucosal antibodies, and specific cellular immunity were detected. Immunizing chicks with avian influenza virus was evaluated. The results showed high levels of IgG in addition to high levels of secretory immunoglobulin A (sIgA) in chickens orally administered recombinant L. plantarum. In addition, the fusion may significantly increase the levels of NP- and M2-specific T cell-mediated immunity in the case of mucosal administration of NC8-pSIP409-pgsA'-NP-M2-FliC. Recombinant NC8-pSIP409-pgsA'-NP-M2-FliC mediated effectively protected chickens against influenza virus and reduced virus titers in the lung. Our study outcomes indicate that the expression of influenza NP-M2 and a mucosal adjuvant (FliC), by L. plantarum could generate a mucosal vaccine candidate for animals in the future to defend against AIVs.

Activity-based protein profiling reveals that secondary-carbon-centered radicals of synthetic 1,2,4-trioxolanes are predominately responsible for modification of protein targets in malaria parasites.

Endoperoxide-containing antimalarials, such as artemisinin and the synthetic trioxolane OZ439, are prodrugs activated by heme to generate primary and secondary carbon-centered radicals. We employed activity-based protein profiling (ABPP) to show that the secondary-carbon-centered radical of 1,2,4-trioxolanes is primarily responsible for protein labeling in malaria parasites.

[Nitrogen mineralization rate in different soil layers and its influence factors under plastic film mulched in Danjiangkou Reservoir area, China]. / ä¸¹æ±Ÿå£åº“åŒºè¦†è†œåœŸå£¤ä¸åŒåœŸå±‚æ°®ç´ çŸ¿åŒ–é€ŸçŽ‡åŠå ¶å½±å“å› ç´ .

The objective of this study was to investigate the rate of nitrogen mineralization in various soil layers (0-10, 10-20, and 20-30 cm) and its influencing factors under plastic film mulching ridge-furrow in a corn field of Wulongchi small watershed, Danjiangkou Reservoir Area. Results showed that the rate of soil ammonification decreased with soil depth during the entire maize growth period. The rate of nitrification in seedling, jointing, and heading stages decreased in the following order: 10-20 cm > 0-10 cm > 20-30 cm, while it increased with soil depth in maturation stage. The rate of soil nitrogen mineralization decreased with the increases in soil depth in the seedling, jointing and heading stages, whereas an opposite pattern was observed in maturation stage. Compared with non-filming, film mulching promoted the soil ammonification process in 0-10 cm and the soil nitrification and nitrogen mineralization processes in jointing, heading, and maturation stages in both 0-10 and 10-20 cm. However, the rates of soil nitrification and nitrogen mineralization under film mulching were much lower than those under non-filming in seedling stage. The stepwise regression analysis indicated that the main factors influencing soil nitrogen mineralization rate varied with soil depth. Soil moisture and total N content were the dominant controller for variation of soil nitrogen mineralization in 0-10 cm layer. Soil temperature, moisture, and total N content were dominant controller for that in 10-20 cm layer. Soil temperature drove the variation of soil nitrogen mineralization in 20-30 cm layer.

Recombinant Lactobacillus plantarum expressing HA2 antigen elicits protective immunity against H9N2 avian influenza virus in chickens.

Low pathogenic H9N2 subtype avian influenza virus (AIV) can lead to moderate respiratory symptoms and low egg production rates in poultry. Due to its immunologic suppression, other various infectious pathogens give rise to the co-infection of hosts, causing heavy economic losses in the commercial poultry industry in both China and worldwide. Therefore, it is time to explore a novel, safe, and effective vaccine. We have already made use of the surface of Lactobacillus plantarum to display AIV HA2 (NC8-pSIP409-pgsA'-HA2), which demonstrated that it has a good immunogenicity. In this study, by evaluating the immune protection effect of NC8-pSIP409-pgsA'-HA2 on chickens, we found that the hemagglutination inhibition (HI) antibodies, specificity IgG antibody in chickens, the sIgA titer in broncho alveolar lavage fluids (BALF), and the T cell response were increased notably after oral vaccination with NC8-pSIP409-pgsA'-HA2. In addition, weight loss, lung titers, and lung pathologies were improved when chickens were orally vaccinated with NC8-pSIP409-pgsA'-HA2 after challenge with H9N2 AIV. This strategy lays the foundation for the development of recombinant L. plantarum oral vaccines in the prevention of AIV.

Willingness to Pay for Measures of Managing the Health Effects of Heat Wave in Beijing, China: a Cross-sectional Survey.

OBJECTIVE: There are evidences that heat wave events cause deaths and emergency cases. This article used the contingent valuation method to find the willingness to pay for the protective measures and investigated the factors that influence the willingness to pay. METHODS: A cross-sectional face-to-face household survey was completed by 637 urban long-term residents and 591 rural long-term residents aged 15-79 in Beijing, China. Binary logistic regression was used to identify factors that influenced the payment rate or payment amount for the protective measures, including independent variables for district, gender, age, education, income, air conditioner ownership, heat wave experience, and chronic non-communicable disease. RESULTS: The payment rate was 41.1% for protective measures provided by the government and 39.5% by measures provided by the market. Most of the respondents were willing to pay 40 CNY per capita annually for measures provided by the government or the market. The factors influencing willingness to pay were district, gender, income, air conditioner ownership, heat wave experience, and chronic non-communicable disease.. CONCLUSION: Protective measures for heat waves need to be provided immediately. More attention should be paid to the situation of vulnerable groups, such as people who live in urban areas, those without air conditioning, and those who have experienced a heat wave in the past.

The complete mitochondrial genome of Bombyx mori strain Jin6 (Lepidoptera: Bombycidae).

In this study, the complete mitochondrial genome of Bombyx mori strain Jin6 (Lepidoptera: Bombycidae) has been reported for the first time. It was a circular molecule of 15,648 bp in length, containing 37 typical coding genes and one non-coding AT-rich region. The overall composition of the mitogenome was A (43.05%), G (7.30%), C (11.35%), and T (38.29%). Its gene order and content were identical to the common type found in most insect mitogenomes. All protein coding genes (PCGs) started with a typical ATN initiation codon, except for the cox1 gene, which began with CGA codon. Eleven genes used standard complete termination codon TAA, whereas the cox1 and cox2 genes ended with single T. All tRNA genes displayed typical secondary cloverleaf structures as those of other insects. Additionally, the 494 bp long AT-rich region contained several structures common to the other lepidopterons, such as some structures of repeated motifs and microsatellite-like elements.

The complete mitochondrial genome of Bombyx mori strain Yu5 (Lepidoptera: Bombycidae).

The complete mitochondrial genome of Bombyx mori strain Yu5 (Lepidoptera: Bombycidae) is a circular molecule of 15,644 bp in length, containing 37 typical coding genes and one non-coding AT-rich region. The overall composition of the mitogenome was A (43.07%), G (7.34%), C (11.33%), and T (38.26%). Its gene order and content were identical to the common type found in most insect mitogenomes. All protein coding genes (PCGs) started with a typical ATN initiation codon, except for the cox1 gene, which began with CGA codon. Eleven genes used standard complete termination codon TAA, whereas the cox1 and cox2 genes ended with single T. All tRNA genes displayed typical secondary cloverleaf structures as those of other insects. Additionally, the 494 bp long AT-rich region contained several structures common to the other lepidopterons, such as some structures of repeated motifs and microsatellite-like elements and a poly-A element upstream of transfer RNA M (trnM) gene.

The complete mitochondrial genome of Bombyx mori strain Yu39 (Lepidoptera: Bombycidae).

The complete mitochondrial genome of Bombyx mori strain Yu39 (Lepidoptera: Bombycidae) is a circular molecule of 15,652 bp in length, containing 37 typical mitochondrial genes: 13 protein-coding genes (PCGs), 22 transfer RNAs, 2 ribosomal RNAs and a non-coding AT-rich region. Its gene order and arrangement are identical to the common type found in most insect mitogenomes. All PCGs start with a typical ATN codon, except for the cox1 gene, which begins with uncertained codon. All PCGs terminate in the common stop codon TAA, except for the cox1 and cox2, which use single T as their stop codons. The non-coding AT-rich region is 494-bp long, located between rrnS and trnM genes. It contains some structures of repeated motifs and microsatellite-like elements characteristic of the other lepidopterons.

The complete mitochondrial genome of Antheraea pernyi strain Yu6 (Lepidoptera: Saturniidae).

In this study, the complete mitochondrial genome of Antheraea pernyi strain Yu6 (Lepidoptera: Saturniidae) has been reported for the first time. It is a circular molecule of 15,569 bp in length, containing 37 typical coding genes and 1 non-coding AT-rich region. The overall composition of the mitogenome is A (39.27%), G (7.71%), C (12.01%), and T (41.01%). Its gene order and content are identical to the common type found in most insect mitogenomes. All protein coding genes (PCGs) start with a typical ATN initiation codon, except for the cox1 gene, which begins with TTAG codon. Nine genes used standard complete termination codon TAA, whereas the cox1, cox2, nad3, and nad5 genes end with single T. All tRNAs display typical secondary cloverleaf structures as those of other insects. Additionally, the 552 bp long AT-rich region contained several structures common to the other lepidopterons, such as some structures of repeated motifs and microsatellite-like elements. Phylogenetic analysis showed that the Antheraea pernyi Yu6 was close to Saturniidae.

Complete mitochondrial genome of Antheraea pernyi strain Yu7 (Lepidoptera: Saturniidae).

The complete mitochondrial genome of Antheraea pernyi strain Yu7 (Lepidoptera: Saturniidae) is a circular molecule of 15,572 bp in length, with 37 typical coding genes and 1 non-coding A T-rich region. All protein coding genes (PCGs) start with a typical ATN initiation codon, except for the cox1 gene, which begins with TTAG codon. Nine genes used standard complete termination codon TAA, whereas the cox1, cox2, nad3 and nad5 genes end with single T. The non-coding AT-rich region is 554 bp long. Phylogenetic analysis showed that the Antheraea pernyi Yu7 was close to Saturniidae.

UV/TiO2 photocatalytic disinfection of carbon-bacteria complexes in activated carbon-filtered water: Laboratory and pilot-scale investigation.

The occurrence of carbon-bacteria complexes in activated carbon filtered water has posed a public health problem regarding the biological safety of drinking water. The application of combined process of ultraviolet radiation and nanostructure titanium dioxide (UV/TiO2) photocatalysis for the disinfection of carbon-bacteria complexes were assessed in this study. Results showed that a 1.07 Lg disinfection rate can be achieved using a UV dose of 20 mJ cm(-2), while the optimal UV intensity was 0.01 mW cm(-2). Particle sizes ≥8 µm decreased the disinfection efficiency, whereas variation in particle number in activated carbon-filtered water did not significantly affect the disinfection efficiency. Photoreactivation ratio was reduced from 12.07% to 1.69% when the UV dose was increased from 5 mJ cm(-2) to 20 mJ cm(-2). Laboratory and on-site pilot-scale experiments have demonstrated that UV/TiO2 photocatalytic disinfection technology is capable of controlling the risk posed by carbon-bacteria complexes and securing drinking water safety.

[Rapid determination of ractopamine content in pork by using three-dimensional synchronous fluorescence spectrum coupled with APTLD].

In order to realize the rapid determination of ractopamine content in pork, quantitative determination model of ractopamine content in pork was established by using three-dimensional synchronous fluorescence spectrum coupled with alternating penalty trilinear decomposition (APTLD). Firstly, the generation mechanism of the fluorescence spectrum for ractopamine and three-dimensional synchronous fluorescence spectrum for samples were analyzed. Secondly, concentration quenching phenomenon of fluorescence of ractopamine in pork extract was investigated. Thirdly, the number of components for three linear decomposition of APTLD was set as 2 by using the core consistency diagnostic method, and the calibration curve of the relative fluorescence intensity of ractopamine between pork extract and the training sample was established for the correction of relative fluorescence intensity of prediction samples. Finally, three-dimensional synchronous fluorescence spectrum combined with APTLD was used to build the prediction model of ractopamine content in pork. The experimental results showed that the method adopted in the paper could better solve the problem of serious synchronous fluorescence spectrum overlapping between ractopamine in pork samples and backgrounds, and leave out some trivial process of chemical separation for the identification of ractopamine in pork. The determination coefficient (R2) and the root mean squared error of prediction (RMSEP) for the model proposed in this paper were 0.986 3 and 0.496 6 mg x L(-1), respectively. The method in this paper has achieved the goal of rapid quantitative detection of ractopamine content in pork.

Predictive and prognostic roles of ribonucleotide reductase M1 in patients with pancreatic cancer treated with gemcitabine: a meta-analysis.

Increasing scientific evidence suggests that ribonucleotide reductase M1 (RRM1) may be a powerful predictor of survival in patients with pancreatic cancer treated with adjuvant gemcitabine-based chemotherapy after operative resection, but many existing studies have yielded inconclusive results. This meta-analysis aimed to assess the prognostic role of RRM1 in predicting survival in patients with pancreatic cancer treated with gemcitabine. An extensive literature search for relevant studies was conducted on PubMed, Embase, Web of Science, Cochrane Library, and CBM databases from their inception through May 1st, 2013. This meta-analysis was performed using the STATA 12.0 software and crude hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated. Eight clinical studies were included in this meta-analysis with a total of 665 pancreatic cancer patients treated with adjuvant gemcitabine-based chemotherapy, including 373 patients in the high RRM1 expression group and 292 patients in the low RRM1 expression group. Our meta-analysis revealed that high RRM1 expression was associated with improved overall survival (OS) of pancreatic cancer patients (HR=1.56, 95%CI=0.95-2.17, P<0.001). High RRM1 expression also was linked to longer disease-free survival (DFS) than low RRM1 expression (HR=1.37, 95%CI=0.25-2.48, P=0.016). In conclusion, our meta-analysis suggests that high RRM1 expression may be associated with improved OS and DFS of pancreatic cancer patients treated with adjuvant gemcitabine-based chemotherapy. Detection of RRM1 expression may be a promising biomarker for gemcitabine response and prognosis in pancreatic cancer patients.

[Rapid determination of tetracycline content in duck meat using particle swarm optimization algorithm and synchronous fluorescence spectrum].

Tetracycline under the condition of NaOH could be degraded to iso tetracycline which has strong fluorescent characteristic, and the prediction model of tetracycline contents in duck meat was developed with the combination of synchronous fluorescence spectrum, wavelet de-noising, particle swarm optimization algorithm (PSO) and support vector regression (SVR), and it could realize the rapid prediction of tetracycline contents in duck meat and improve the accuracy of prediction model. In the process, 70 nm was selected as the optimum wavelength difference for the determination of tetracycline contents in duck meat by using parallel factor analysis (PARAFAC). Secondly, the db6 wavelet with 2 levels decomposition was used to reduce the noise of synchronous fluorescence spectrum, and the spectrum after wavelet de-noising was normalized, and 6 characteristic wavelengths were selected by using PSO. Lastly, the SVR model parameters (c, g) were optimized by using PSO. Furthermore, the performances of the models of PSO-SVR, PLS and PCR under the spectral condition of characteristic wavelengths selected by using PSO, and PSO-SVR under the spectral condition of full spectrum were compared. The experimental results showed that the predictive ability of the model of PSO-SVR under the spectral condition of characteristic wavelengths selected by using PSO was strongest, and the correlation coefficient and the root mean squared error of prediction were 0.952 0 and 17.6 mg x kg(-1), respectively. This work proved that PSO could extract effectively the characteristic wavelengths of tetracycline in duck meat, and the model of PSO-SVR could satisfy the request of rapid determination of tetracycline contents in duck meat.

[Study on determination of carbaryl content in duck meat based on synchronous fluorescence spectroscopy].

For the rapid detection of carbaryl residue in duck meat, synchronous fluorescence spectroscopy was used, and GA combined with SVR was used to establish regression forecasting mode for the application of forecasting carbaryl residue in duck meat. Firstly, fluorescence spectrophotometer was used to get the 3D synchronous fluorescence spectra of carbaryl hydrolysate and duck solution containing carbaryl, and 140 nm was selected as the optimum wavelength difference delta lambda; Secondly, some concentration quenching was analysed. Finally, GA was used to optimize and choose the 3D synchronous fluorescence spectra. According to the root mean square error of cross-validation (RMSECV) 21 characteristic wavelengths were chosen, then the full wavelength and 21 characteristic wavelengths were used as input characteristic variables of SVR regression forecasting model respectively. At last the results showed that characteristic wavelengths chosen by GA can get better forecasting results, and the correlation coefficient of the prediction samples set and the root mean squared error (RMSEP) were 0.976 4 and 12.232 2, respectively. The results of experiments showed that the synchronous fluorescence spectroscopy could be used to detect carbaryl residue in duck meat efficiently and rapidly when combined with GA-SVR.