Huanchun Chen - Academia.edu (original) (raw)
Papers by Huanchun Chen
Oncotarget, Jan 26, 2016
Bovine herpesvirus 1 (BoHV-1) UL51 protein (pUL51) is a tegument protein of BoHV-1 whose function... more Bovine herpesvirus 1 (BoHV-1) UL51 protein (pUL51) is a tegument protein of BoHV-1 whose function is currently unknown. Here, we aimed to illustrate the specific role of pUL51 in virion morphogenesis and its importance in BoHV-1 virulence. To do so, we constructed a BoHV-1 bacterial artificial chromosome (BAC). We used recombinant BAC and transgenic techniques to delete a major part of the UL51 open reading frame. Deletion of pUL51 resulted in severe viral growth defects, as evidenced by lower single and multi-step growth kinetics, reduced plaque size, and the accumulation of non-enveloped capsids in the cytoplasm of infected cells. Using tagged BoHV-1 recombinant viruses, it was determined that the pUL51 protein completely co-localized with the cis-Golgi marker protein GM-130. Taken altogether, pUL51 was demonstrated to play a critical role in BoHV-1 growth and it is involved in viral maturation and egress. Moreover, an in vivo analysis showed that the pUL51 mutant exhibited reduce...
Journal of virology, Jan 2, 2016
Japanese encephalitis virus (JEV) can invade the central nervous system, and consequently induce ... more Japanese encephalitis virus (JEV) can invade the central nervous system, and consequently induce neuroinflammation, which is characterized by profound neuronal cells damage accompanied by astrogliosis and microgliosis. Albeit microRNAs (miRNAs) have emerged as major regulatory non-coding RNAs with profound effects on inflammatory response, it is unknown how astrocytic miRNAs regulate JEV-induced inflammation. Here, we found the involvement of miR-19b-3p in regulating JEV-induced inflammatory response in vitro and in vivo. The data demonstrated that miR-19b-3p is up-regulated in cultured cells and mice brain tissues during JEV infection. Overexpression of miR-19b-3p led to increased production of inflammatory cytokines, including tumor necrosis factor-α, interleukin-6, interleukin-1β, and chemokine (C-C motif) ligand 5, after JEV infection, whereas knockdown of miR-19b-3p had completely opposite effects. Mechanistically, miR-19b-3p modulated the JEV-induced inflammatory response via ...
Standards in Genomic Sciences, 2016
Avian pathogenic Escherichia coli is an important etiological agent of avian colibacillosis, whic... more Avian pathogenic Escherichia coli is an important etiological agent of avian colibacillosis, which manifests as respiratory, hematogenous, meningitic, and enteric infections in poultry. It is also a potential zoonotic threat to human health. The diverse genomes of APEC strains largely hinder disease prevention and control measures. In the current study, pyrosequencing was used to analyze and characterize APEC strain ACN001 (= CCTCC 2015182(T) = DSMZ 29979(T)), which was isolated from the liver of a diseased chicken in China in 2010. Strain ACN001 belongs to extraintestinal pathogenic E. coli phylogenetic group B1, and was highly virulent in chicken and mouse models. Whole genome analysis showed that it consists of six different plasmids along with a circular chromosome of 4,936,576 bp, comprising 4,794 protein-coding genes, 108 RNA genes, and 51 pseudogenes, with an average G + C content of 50.56 %. As well as 237 coding sequences, we identified 39 insertion sequences, 12 predicated genomic islands, 8 prophage-related sequences, and 2 clustered regularly interspaced short palindromic repeats regions on the chromosome, suggesting the possible occurrence of horizontal gene transfer in this strain. In addition, most of the virulence and antibiotic resistance genes were located on the plasmids, which would assist in the distribution of pathogenicity and multidrug resistance elements among E. coli populations. Together, the information provided here on APEC isolate ACN001 will assist in future study of APEC strains, and aid in the development of control measures.
Http Dx Doi Org 10 1080 02508060508691864, Jan 22, 2009
Human activities and climatic change have greatly impacted hydrological cycles and water resource... more Human activities and climatic change have greatly impacted hydrological cycles and water resources planning in the Yellow River basin. In order to assess these impacts, a semi-distributed monthly water balance model was proposed and developed to simulate and predict the hydrological processes in the middle and lower Yellow River basin. GIS techniques were used as a tool to analyze topography, river networks, land-use, human activities, vegetation, and soil characteristics. The model parameters were calibrated in 35 gauged sub-basins in the middle Yellow River, and then the relationships between the model parameters and the basin physical characteristics were established. A parameterization scheme was developed in which the model parameters were estimated for each grid element by regression and optimization methods. Based on the different outputs of general circulation models (GCMs) and regional climate models (RCMs), the sensitivities to global warming of hydrology and water resources for the Yellow River basin were studied. The proposed models are capable of producing both the magnitude and timing of runoff and water resources conditions. The runoffs are found to be very sensitive to temperature increases and rainfall decreases. Results of the study also indicated that runoff is more sensitive to variation in precipitation than to increase in temperature. The additional uncertainty of climate change has posed a challenge to the existing water resources management practices, and the integration of water resources management will be necessary to enhance the water use efficiency in the Yellow River basin.
Spie Proceedings Series, 2005
Http Dx Doi Org 10 1080 01496395 2013 811424, Oct 18, 2013
Journal of the American Oil Chemists Society, May 1, 1997
A fungal isolate Wuji-H4 with a dense-lobe rosette growth pattern on malt extract agar was identi... more A fungal isolate Wuji-H4 with a dense-lobe rosette growth pattern on malt extract agar was identified as Mortierella alpina Peyronel. It was capable of producing 504 mg/L of arachidonic acid (AA) in the screening medium. Its AA content accounted for 42.4% of the total fatty acids. The AA yield was raised to 1,817 mg/L by a step-by-step approach, which uncovered
Scientific reports, 2015
Mycobacterium tuberculosis (Mtb) remains a leading cause of morbidity and mortality worldwide, as... more Mycobacterium tuberculosis (Mtb) remains a leading cause of morbidity and mortality worldwide, as two billion people are latently infected with Mtb. To address Mtb drug resistance and the limitations of current vaccines, the characteristics of candidate Mtb vaccines need to be explored. Here, we report the three-dimensional structure of Rv0315 at 1.70 Å resolution, a novel immunostimulatory antigen of Mtb, and demonstrate that Rv0315 is an inactive β-1,3-glucanase of the glycoside hydrolase 16 (GH16) family. Our study further elaborates the molecular basis for the lack of glucan recognition by Rv0315. Rv0315 has a large open groove, and this particular topology cannot bind oligosaccharide chains in solution, thus explaining the lack of detectable hydrolytic activity towards its substrate. Additionally, we identified Glu-176, a conserved catalytic residue in GH16 endo-β-1,3-glucanases, as essential for Rv0315 to induce immunological responses. These results indicate that Rv0315 likel...
Scientific reports, 2015
H5N1 influenza A virus (IAV) causes severe respiratory diseases and high mortality rates in anima... more H5N1 influenza A virus (IAV) causes severe respiratory diseases and high mortality rates in animals and humans. MicroRNAs are being increasingly studied to evaluate their potential as therapeutic entities to combat viral infection. However, mechanistic studies delineating the roles of microRNAs in regulating host-H5N1 virus interactions remain scarce. Here, we performed microRNA microarray analysis using A549 human lung epithelial cells infected with a highly pathogenic avian influenza virus. The microRNA expression profile of infected cells identified a small number of microRNAs being dysregulated upon H5N1 influenza A virus infection. Of the differentially expressed microRNAs, miR-136 was up-regulated 5-fold and exhibited potent antiviral activity in vitro against H5N1 influenza A virus, as well as vesicular stomatitis virus. On the one hand, 3'-untranslated region (UTR) reporter analysis revealed a miR-136 binding site in the 3' UTR of IL-6. However, on the other hand, we...
Infection and immunity, Jan 8, 2015
The highly pathogenic Streptococcus suis (S. suis) infection can cause septic shock, and the dise... more The highly pathogenic Streptococcus suis (S. suis) infection can cause septic shock, and the disease is characterized by a high level of inflammatory cytokines and high mortality. Our previous study indicated that TREM-1 (triggering receptor expressed onmyeloid cells 1) was up-regulated in swine spleen cells in response to S. suis infection. The role of TREM-1 signaling in enhancing the pro-inflammatory response promoted us to examine its effect on the outcome of S. suis infection. In the present study, the recombinant extracellular domain of TREM-1 (rTREM-1) and an agonistic TREM-1 antibody was used to inhibit and activate TREM-1 signaling to evaluate its role in neutrophil activation, pathogen clearance, pro-inflammatory cytokine response and the outcome of the highly pathogenic S. suis infection in a mouse model. Blocking TREM-1 signaling could cause a more severe pro-inflammatory response and increase mortality in response to S. suis infection, while its activation could exert t...
PloS one, 2015
To determine the nationwide status of persistent BVDV infection in different bovine species in Ch... more To determine the nationwide status of persistent BVDV infection in different bovine species in China and compare different test methods, a total of 1379 serum samples from clinical healthy dairy cattle, beef cattle, yaks (Bos grunniens), and water buffalo (Bubalus bubalis) were collected in eight provinces of China from 2010 to 2013. The samples were analyzed using commercial antibody (Ab) and antigen (Ag) detection kits, and RT-PCR based on the 5'-UTR and Npro gene sequencing. Results showed that the overall positive rates for BVDV Ab, Ag and RT-PCR detection were 58.09% (801/1379), 1.39% (14/1010), and 22.64% (146/645), respectively, while the individual positive rates varied among regions, species, and farms. The average Ab-positive rates for dairy cattle, beef cattle, yaks, and water buffalo were 89.49% (298/333), 63.27% (248/392), 45.38% (236/520), and 14.18% (19/134), respectively, while the Ag-positive rates were 0.00% (0/116), 0.77% (3/392), 0.82% (3/368), and 5.97% (8/1...
PloS one, 2014
Streptococcus suis serotype 2 is an important zoonotic pathogen causing severe infections in pigs... more Streptococcus suis serotype 2 is an important zoonotic pathogen causing severe infections in pigs and humans. The pathogenesis of S. suis 2 infections, however, is still poorly understood. Spx proteins are a group of global regulators involved in stress tolerance and virulence. In this study, we characterized two orthologs of the Spx regulator, SpxA1 and SpxA2 in S. suis 2. Two mutant strains (ΔspxA1 and ΔspxA2) lacking the spx genes were constructed. The ΔspxA1 and ΔspxA2 mutants displayed different phenotypes. ΔspxA1 exhibited impaired growth in the presence of hydrogen peroxide, while ΔspxA2 exhibited impaired growth in the presence of SDS and NaCl. Both mutants were defective in medium lacking newborn bovine serum. Using a murine infection model, we demonstrated that the abilities of the mutant strains to colonize the tissues were significantly reduced compared to that of the wild-type strain. The mutant strains also showed a decreased level of survival in pig blood. Microarray ...
BioMed research international, 2013
Antihypertensive drugs have been linked to new-onset diabetes (NOD); however, data on the effect ... more Antihypertensive drugs have been linked to new-onset diabetes (NOD); however, data on the effect of these drugs on the development of NOD in hypertensive patients has not been well determined in a clinical setting. The aim was to investigate the association between antihypertensive drugs and NOD in Taiwan. We conducted a retrospective study of hypertensive Taiwanese patients receiving antihypertensive drugs treatment between January 2006 and December 2011. Clinical information and laboratory parameters were collected by reviewing the medical records. We estimated the odds ratios (ORs) of NOD associated with antihypertensive drug use; nondiabetic subjects served as the reference group. A total of 120 NOD cases were identified in 1001 hypertensive patients during the study period. The risk of NOD after adjusting sex, age, baseline characteristics, and lipid profiles was higher among users of thiazide diuretics (OR, 1.65; 95% confidence interval (CI), 1.12-2.45) and nondihydropyridine ...
Virus genes, 2006
S1 gene fragment containing receptor-binding region was amplified by several sets of primers usin... more S1 gene fragment containing receptor-binding region was amplified by several sets of primers using Over-Lap PCR. The native S1 gene was modified at A + T abundant regions; n.t.777-1683, n.t.1041-1050, n.t.1236-1248, n.t.1317-1335, n.t.1590-1605; based on the same amino acid sequences. The modified gene was cloned into a yeast expression vector pPIC9K. The resultant plasmid pPIC9K- S1 was transformed into Pichia pastoris GS 115 and the protein expression was induced with methanol. SDS-PAGE confirmed that the recombinant SI was secreted in the supernatant of induced GS 115. The protein yield reached 69 mg/l. ELISA and Western blot demonstrated that the S1 could react with the convalescent sera of people infected by SARS-CoV. Furthermore, ligand blot assay showed that the recombinant S1 could react with ACE2, the receptor of SARS-CoV. The molecular mass of expressed S1 was about 70 kDa, which was higher than that of the 30 kDa expected. PNGase F deglycosylation resulted in a protein ba...
Vaccine, Jan 25, 2015
Streptococcus suis serotype 2 (S. suis 2) is an important zoonotic pathogen that can also cause e... more Streptococcus suis serotype 2 (S. suis 2) is an important zoonotic pathogen that can also cause epidemics of life-threatening infections in humans. Surface proteins of pathogens play a critical role in the interaction with host system or environment, as they take part in processes like virulence, cytotoxicity, adhesion, signaling or transport, etc. Thus, surface proteins identified by the screening of immunoproteomic techniques are promising vaccine candidates or diagnostic markers. In this study, four membrane associated proteins (MAP) identified by immunoproteomic method were cloned and expressed as recombinant proteins with his-tag. Screening for vaccine candidates were firstly performed by protection assay in vivo and immunization with Sbp markedly protected mice against systemic S. suis 2 infection. The immune responses and protective of Sbp were further evaluated. The results showed that Sbp could elicit a strong humoral antibody response and protect mice from lethal challenge...
Vaccine, 2009
Haemophilus parasuis is the aetiological agent of Glässer's disease, which is responsible for... more Haemophilus parasuis is the aetiological agent of Glässer's disease, which is responsible for cases of fibrinous polyserositis, polyarthritis and meningitis in young pigs. To develop more effective vaccines, an immunoproteome-based approach was used to analyze the outer membrane proteins of H. parasuis serovar 5. A total of 15 proteins with high immunogenicity were identified and all were showed to be
Euphytica, 2014
ABSTRACT Salinity is a major constraint to the sustainability and expansion of maize cultivation.... more ABSTRACT Salinity is a major constraint to the sustainability and expansion of maize cultivation. Plant salt tolerance is a quantitative trait controlled by multiple genes. In the present study, we constructed a high density genetic map based on high quality SNP markers from 161 F2:5 recombinant inbred line populations derived from the cross between two maize inbred lines contrasting in salinity tolerance. QTL analysis was conducted in saline field and the hydroponic culture. For saline field, field germination rate and field salt tolerance ranking were used as salinity tolerance indicators to conduct QTL detection. For hydroponic culture, salt tolerance ranking, shoot fresh weight, shoot dry weight, tissue water content, shoot Na+ concentration, shoot K+ concentration, and shoot K+/Na+ ratio were used. Through unconditional QTL analysis, we detected 20 additive and nine epistatic QTLs, of which 12 and two showed significant QTL by treatment (Q × T) interaction effects, respectively. Moreover, the use of conditional analysis model allowed us to detect nine conditional QTLs. The QTLs were mainly clustered on chromosomes 1, 3 and 5. The five unconditional and three conditional QTLs reported here could individually explain more than 20 % of the phenotypic variation. The QTLs identified here could be helpful to improve salt tolerance in maize by marker-assisted selection and shed new light on understanding the genetic basis of salt tolerance in maize.
Injury, 2015
Haemorrhagic shock after traumatic injury carries a high mortality. Therapeutic hypothermia has b... more Haemorrhagic shock after traumatic injury carries a high mortality. Therapeutic hypothermia has been widely used in critical illness to improve the outcome in haemorrhagic shock by activation of cardiac pro-survival signalling pathways. However, the role played by the mitochondria in the cardioprotective effects of therapeutic hypothermia remains unclear. We investigated the effects of therapeutic hypothermia on mitochondrial function and integrity after haemorrhagic shock using an in vitro ischaemia-reperfusion model. H9c2 cardiomyocytes received a simulated ischaemic reperfusion injury under normothermic (37°C) and hypothermic (31°C) conditions. The cardiomyocytes were treated with hypoxic condition for 18h in serum-free, glucose-free culture medium at pH 6.9 and then shifted to re-oxygenation status for 6h in serum-containing cell culture medium at pH 7.4. Cellular survival, mitochondrial integrity, energy metabolism and calcium homeostasis were studied. Hypothermia treatment les...
Journal of Clinical Biochemistry and Nutrition, 2014
Type 2 diabetes is a risk factor for Alzheimer&am... more Type 2 diabetes is a risk factor for Alzheimer's disease and mild cognitive impairment. Folate insufficiency fosters a decline in the sole methyl donor, S-adenosylmethionine, and decreases methylation potential, which is associated with Alzheimer's disease in non-diabetic patients. However, little is known in diabetic patients. We analyzed plasma levels of S-adenosylmethionine, S-adenosylhomocysteine and serum level of folate in 100 elderly type 2 diabetic patients with and without mild cognitive impairment. S-adenosylmethionine/S-adenosylhomocysteine ratio was used to reflect the methylation potential. Patients with mild cognitive impairment had significantly lower levels of S-adenosylmethionine, folate and S-adenosylmethionine/S-adenosylhomocysteineratios. Furthermore, logistic regression analysis indicated the plasma S-adenosylmethionine, S-adenosylmethionine/S-adenosylhomocysteine ratio and serum folate (OR, 0.96, 0.698, 0.72, respectively; p<0.05) were negatively associated with risk of mild cognitive impairment, even after adjusting for related covariates. In addition, folate level was positively correlated with S-adenosylmethionine and the S-adenosylmethionine/S-adenosylhomocysteine ratio (r = 0.38, 0.46, respectively; p<0.05) among patients within the middle tertile of folate levels (6.3-9.1 µg/L). These findings indicate mild cognitive impairment is associated with lower levels of S-adenosylmethionine, folate and weakened methylation potential; plasma S-adenosylmethionine and methylation potential may be predicted by serum folate within a suitable range of folate concentrations in diabetic patients.
Oncotarget, Jan 26, 2016
Bovine herpesvirus 1 (BoHV-1) UL51 protein (pUL51) is a tegument protein of BoHV-1 whose function... more Bovine herpesvirus 1 (BoHV-1) UL51 protein (pUL51) is a tegument protein of BoHV-1 whose function is currently unknown. Here, we aimed to illustrate the specific role of pUL51 in virion morphogenesis and its importance in BoHV-1 virulence. To do so, we constructed a BoHV-1 bacterial artificial chromosome (BAC). We used recombinant BAC and transgenic techniques to delete a major part of the UL51 open reading frame. Deletion of pUL51 resulted in severe viral growth defects, as evidenced by lower single and multi-step growth kinetics, reduced plaque size, and the accumulation of non-enveloped capsids in the cytoplasm of infected cells. Using tagged BoHV-1 recombinant viruses, it was determined that the pUL51 protein completely co-localized with the cis-Golgi marker protein GM-130. Taken altogether, pUL51 was demonstrated to play a critical role in BoHV-1 growth and it is involved in viral maturation and egress. Moreover, an in vivo analysis showed that the pUL51 mutant exhibited reduce...
Journal of virology, Jan 2, 2016
Japanese encephalitis virus (JEV) can invade the central nervous system, and consequently induce ... more Japanese encephalitis virus (JEV) can invade the central nervous system, and consequently induce neuroinflammation, which is characterized by profound neuronal cells damage accompanied by astrogliosis and microgliosis. Albeit microRNAs (miRNAs) have emerged as major regulatory non-coding RNAs with profound effects on inflammatory response, it is unknown how astrocytic miRNAs regulate JEV-induced inflammation. Here, we found the involvement of miR-19b-3p in regulating JEV-induced inflammatory response in vitro and in vivo. The data demonstrated that miR-19b-3p is up-regulated in cultured cells and mice brain tissues during JEV infection. Overexpression of miR-19b-3p led to increased production of inflammatory cytokines, including tumor necrosis factor-α, interleukin-6, interleukin-1β, and chemokine (C-C motif) ligand 5, after JEV infection, whereas knockdown of miR-19b-3p had completely opposite effects. Mechanistically, miR-19b-3p modulated the JEV-induced inflammatory response via ...
Standards in Genomic Sciences, 2016
Avian pathogenic Escherichia coli is an important etiological agent of avian colibacillosis, whic... more Avian pathogenic Escherichia coli is an important etiological agent of avian colibacillosis, which manifests as respiratory, hematogenous, meningitic, and enteric infections in poultry. It is also a potential zoonotic threat to human health. The diverse genomes of APEC strains largely hinder disease prevention and control measures. In the current study, pyrosequencing was used to analyze and characterize APEC strain ACN001 (= CCTCC 2015182(T) = DSMZ 29979(T)), which was isolated from the liver of a diseased chicken in China in 2010. Strain ACN001 belongs to extraintestinal pathogenic E. coli phylogenetic group B1, and was highly virulent in chicken and mouse models. Whole genome analysis showed that it consists of six different plasmids along with a circular chromosome of 4,936,576 bp, comprising 4,794 protein-coding genes, 108 RNA genes, and 51 pseudogenes, with an average G + C content of 50.56 %. As well as 237 coding sequences, we identified 39 insertion sequences, 12 predicated genomic islands, 8 prophage-related sequences, and 2 clustered regularly interspaced short palindromic repeats regions on the chromosome, suggesting the possible occurrence of horizontal gene transfer in this strain. In addition, most of the virulence and antibiotic resistance genes were located on the plasmids, which would assist in the distribution of pathogenicity and multidrug resistance elements among E. coli populations. Together, the information provided here on APEC isolate ACN001 will assist in future study of APEC strains, and aid in the development of control measures.
Http Dx Doi Org 10 1080 02508060508691864, Jan 22, 2009
Human activities and climatic change have greatly impacted hydrological cycles and water resource... more Human activities and climatic change have greatly impacted hydrological cycles and water resources planning in the Yellow River basin. In order to assess these impacts, a semi-distributed monthly water balance model was proposed and developed to simulate and predict the hydrological processes in the middle and lower Yellow River basin. GIS techniques were used as a tool to analyze topography, river networks, land-use, human activities, vegetation, and soil characteristics. The model parameters were calibrated in 35 gauged sub-basins in the middle Yellow River, and then the relationships between the model parameters and the basin physical characteristics were established. A parameterization scheme was developed in which the model parameters were estimated for each grid element by regression and optimization methods. Based on the different outputs of general circulation models (GCMs) and regional climate models (RCMs), the sensitivities to global warming of hydrology and water resources for the Yellow River basin were studied. The proposed models are capable of producing both the magnitude and timing of runoff and water resources conditions. The runoffs are found to be very sensitive to temperature increases and rainfall decreases. Results of the study also indicated that runoff is more sensitive to variation in precipitation than to increase in temperature. The additional uncertainty of climate change has posed a challenge to the existing water resources management practices, and the integration of water resources management will be necessary to enhance the water use efficiency in the Yellow River basin.
Spie Proceedings Series, 2005
Http Dx Doi Org 10 1080 01496395 2013 811424, Oct 18, 2013
Journal of the American Oil Chemists Society, May 1, 1997
A fungal isolate Wuji-H4 with a dense-lobe rosette growth pattern on malt extract agar was identi... more A fungal isolate Wuji-H4 with a dense-lobe rosette growth pattern on malt extract agar was identified as Mortierella alpina Peyronel. It was capable of producing 504 mg/L of arachidonic acid (AA) in the screening medium. Its AA content accounted for 42.4% of the total fatty acids. The AA yield was raised to 1,817 mg/L by a step-by-step approach, which uncovered
Scientific reports, 2015
Mycobacterium tuberculosis (Mtb) remains a leading cause of morbidity and mortality worldwide, as... more Mycobacterium tuberculosis (Mtb) remains a leading cause of morbidity and mortality worldwide, as two billion people are latently infected with Mtb. To address Mtb drug resistance and the limitations of current vaccines, the characteristics of candidate Mtb vaccines need to be explored. Here, we report the three-dimensional structure of Rv0315 at 1.70 Å resolution, a novel immunostimulatory antigen of Mtb, and demonstrate that Rv0315 is an inactive β-1,3-glucanase of the glycoside hydrolase 16 (GH16) family. Our study further elaborates the molecular basis for the lack of glucan recognition by Rv0315. Rv0315 has a large open groove, and this particular topology cannot bind oligosaccharide chains in solution, thus explaining the lack of detectable hydrolytic activity towards its substrate. Additionally, we identified Glu-176, a conserved catalytic residue in GH16 endo-β-1,3-glucanases, as essential for Rv0315 to induce immunological responses. These results indicate that Rv0315 likel...
Scientific reports, 2015
H5N1 influenza A virus (IAV) causes severe respiratory diseases and high mortality rates in anima... more H5N1 influenza A virus (IAV) causes severe respiratory diseases and high mortality rates in animals and humans. MicroRNAs are being increasingly studied to evaluate their potential as therapeutic entities to combat viral infection. However, mechanistic studies delineating the roles of microRNAs in regulating host-H5N1 virus interactions remain scarce. Here, we performed microRNA microarray analysis using A549 human lung epithelial cells infected with a highly pathogenic avian influenza virus. The microRNA expression profile of infected cells identified a small number of microRNAs being dysregulated upon H5N1 influenza A virus infection. Of the differentially expressed microRNAs, miR-136 was up-regulated 5-fold and exhibited potent antiviral activity in vitro against H5N1 influenza A virus, as well as vesicular stomatitis virus. On the one hand, 3'-untranslated region (UTR) reporter analysis revealed a miR-136 binding site in the 3' UTR of IL-6. However, on the other hand, we...
Infection and immunity, Jan 8, 2015
The highly pathogenic Streptococcus suis (S. suis) infection can cause septic shock, and the dise... more The highly pathogenic Streptococcus suis (S. suis) infection can cause septic shock, and the disease is characterized by a high level of inflammatory cytokines and high mortality. Our previous study indicated that TREM-1 (triggering receptor expressed onmyeloid cells 1) was up-regulated in swine spleen cells in response to S. suis infection. The role of TREM-1 signaling in enhancing the pro-inflammatory response promoted us to examine its effect on the outcome of S. suis infection. In the present study, the recombinant extracellular domain of TREM-1 (rTREM-1) and an agonistic TREM-1 antibody was used to inhibit and activate TREM-1 signaling to evaluate its role in neutrophil activation, pathogen clearance, pro-inflammatory cytokine response and the outcome of the highly pathogenic S. suis infection in a mouse model. Blocking TREM-1 signaling could cause a more severe pro-inflammatory response and increase mortality in response to S. suis infection, while its activation could exert t...
PloS one, 2015
To determine the nationwide status of persistent BVDV infection in different bovine species in Ch... more To determine the nationwide status of persistent BVDV infection in different bovine species in China and compare different test methods, a total of 1379 serum samples from clinical healthy dairy cattle, beef cattle, yaks (Bos grunniens), and water buffalo (Bubalus bubalis) were collected in eight provinces of China from 2010 to 2013. The samples were analyzed using commercial antibody (Ab) and antigen (Ag) detection kits, and RT-PCR based on the 5'-UTR and Npro gene sequencing. Results showed that the overall positive rates for BVDV Ab, Ag and RT-PCR detection were 58.09% (801/1379), 1.39% (14/1010), and 22.64% (146/645), respectively, while the individual positive rates varied among regions, species, and farms. The average Ab-positive rates for dairy cattle, beef cattle, yaks, and water buffalo were 89.49% (298/333), 63.27% (248/392), 45.38% (236/520), and 14.18% (19/134), respectively, while the Ag-positive rates were 0.00% (0/116), 0.77% (3/392), 0.82% (3/368), and 5.97% (8/1...
PloS one, 2014
Streptococcus suis serotype 2 is an important zoonotic pathogen causing severe infections in pigs... more Streptococcus suis serotype 2 is an important zoonotic pathogen causing severe infections in pigs and humans. The pathogenesis of S. suis 2 infections, however, is still poorly understood. Spx proteins are a group of global regulators involved in stress tolerance and virulence. In this study, we characterized two orthologs of the Spx regulator, SpxA1 and SpxA2 in S. suis 2. Two mutant strains (ΔspxA1 and ΔspxA2) lacking the spx genes were constructed. The ΔspxA1 and ΔspxA2 mutants displayed different phenotypes. ΔspxA1 exhibited impaired growth in the presence of hydrogen peroxide, while ΔspxA2 exhibited impaired growth in the presence of SDS and NaCl. Both mutants were defective in medium lacking newborn bovine serum. Using a murine infection model, we demonstrated that the abilities of the mutant strains to colonize the tissues were significantly reduced compared to that of the wild-type strain. The mutant strains also showed a decreased level of survival in pig blood. Microarray ...
BioMed research international, 2013
Antihypertensive drugs have been linked to new-onset diabetes (NOD); however, data on the effect ... more Antihypertensive drugs have been linked to new-onset diabetes (NOD); however, data on the effect of these drugs on the development of NOD in hypertensive patients has not been well determined in a clinical setting. The aim was to investigate the association between antihypertensive drugs and NOD in Taiwan. We conducted a retrospective study of hypertensive Taiwanese patients receiving antihypertensive drugs treatment between January 2006 and December 2011. Clinical information and laboratory parameters were collected by reviewing the medical records. We estimated the odds ratios (ORs) of NOD associated with antihypertensive drug use; nondiabetic subjects served as the reference group. A total of 120 NOD cases were identified in 1001 hypertensive patients during the study period. The risk of NOD after adjusting sex, age, baseline characteristics, and lipid profiles was higher among users of thiazide diuretics (OR, 1.65; 95% confidence interval (CI), 1.12-2.45) and nondihydropyridine ...
Virus genes, 2006
S1 gene fragment containing receptor-binding region was amplified by several sets of primers usin... more S1 gene fragment containing receptor-binding region was amplified by several sets of primers using Over-Lap PCR. The native S1 gene was modified at A + T abundant regions; n.t.777-1683, n.t.1041-1050, n.t.1236-1248, n.t.1317-1335, n.t.1590-1605; based on the same amino acid sequences. The modified gene was cloned into a yeast expression vector pPIC9K. The resultant plasmid pPIC9K- S1 was transformed into Pichia pastoris GS 115 and the protein expression was induced with methanol. SDS-PAGE confirmed that the recombinant SI was secreted in the supernatant of induced GS 115. The protein yield reached 69 mg/l. ELISA and Western blot demonstrated that the S1 could react with the convalescent sera of people infected by SARS-CoV. Furthermore, ligand blot assay showed that the recombinant S1 could react with ACE2, the receptor of SARS-CoV. The molecular mass of expressed S1 was about 70 kDa, which was higher than that of the 30 kDa expected. PNGase F deglycosylation resulted in a protein ba...
Vaccine, Jan 25, 2015
Streptococcus suis serotype 2 (S. suis 2) is an important zoonotic pathogen that can also cause e... more Streptococcus suis serotype 2 (S. suis 2) is an important zoonotic pathogen that can also cause epidemics of life-threatening infections in humans. Surface proteins of pathogens play a critical role in the interaction with host system or environment, as they take part in processes like virulence, cytotoxicity, adhesion, signaling or transport, etc. Thus, surface proteins identified by the screening of immunoproteomic techniques are promising vaccine candidates or diagnostic markers. In this study, four membrane associated proteins (MAP) identified by immunoproteomic method were cloned and expressed as recombinant proteins with his-tag. Screening for vaccine candidates were firstly performed by protection assay in vivo and immunization with Sbp markedly protected mice against systemic S. suis 2 infection. The immune responses and protective of Sbp were further evaluated. The results showed that Sbp could elicit a strong humoral antibody response and protect mice from lethal challenge...
Vaccine, 2009
Haemophilus parasuis is the aetiological agent of Glässer's disease, which is responsible for... more Haemophilus parasuis is the aetiological agent of Glässer's disease, which is responsible for cases of fibrinous polyserositis, polyarthritis and meningitis in young pigs. To develop more effective vaccines, an immunoproteome-based approach was used to analyze the outer membrane proteins of H. parasuis serovar 5. A total of 15 proteins with high immunogenicity were identified and all were showed to be
Euphytica, 2014
ABSTRACT Salinity is a major constraint to the sustainability and expansion of maize cultivation.... more ABSTRACT Salinity is a major constraint to the sustainability and expansion of maize cultivation. Plant salt tolerance is a quantitative trait controlled by multiple genes. In the present study, we constructed a high density genetic map based on high quality SNP markers from 161 F2:5 recombinant inbred line populations derived from the cross between two maize inbred lines contrasting in salinity tolerance. QTL analysis was conducted in saline field and the hydroponic culture. For saline field, field germination rate and field salt tolerance ranking were used as salinity tolerance indicators to conduct QTL detection. For hydroponic culture, salt tolerance ranking, shoot fresh weight, shoot dry weight, tissue water content, shoot Na+ concentration, shoot K+ concentration, and shoot K+/Na+ ratio were used. Through unconditional QTL analysis, we detected 20 additive and nine epistatic QTLs, of which 12 and two showed significant QTL by treatment (Q × T) interaction effects, respectively. Moreover, the use of conditional analysis model allowed us to detect nine conditional QTLs. The QTLs were mainly clustered on chromosomes 1, 3 and 5. The five unconditional and three conditional QTLs reported here could individually explain more than 20 % of the phenotypic variation. The QTLs identified here could be helpful to improve salt tolerance in maize by marker-assisted selection and shed new light on understanding the genetic basis of salt tolerance in maize.
Injury, 2015
Haemorrhagic shock after traumatic injury carries a high mortality. Therapeutic hypothermia has b... more Haemorrhagic shock after traumatic injury carries a high mortality. Therapeutic hypothermia has been widely used in critical illness to improve the outcome in haemorrhagic shock by activation of cardiac pro-survival signalling pathways. However, the role played by the mitochondria in the cardioprotective effects of therapeutic hypothermia remains unclear. We investigated the effects of therapeutic hypothermia on mitochondrial function and integrity after haemorrhagic shock using an in vitro ischaemia-reperfusion model. H9c2 cardiomyocytes received a simulated ischaemic reperfusion injury under normothermic (37°C) and hypothermic (31°C) conditions. The cardiomyocytes were treated with hypoxic condition for 18h in serum-free, glucose-free culture medium at pH 6.9 and then shifted to re-oxygenation status for 6h in serum-containing cell culture medium at pH 7.4. Cellular survival, mitochondrial integrity, energy metabolism and calcium homeostasis were studied. Hypothermia treatment les...
Journal of Clinical Biochemistry and Nutrition, 2014
Type 2 diabetes is a risk factor for Alzheimer&am... more Type 2 diabetes is a risk factor for Alzheimer's disease and mild cognitive impairment. Folate insufficiency fosters a decline in the sole methyl donor, S-adenosylmethionine, and decreases methylation potential, which is associated with Alzheimer's disease in non-diabetic patients. However, little is known in diabetic patients. We analyzed plasma levels of S-adenosylmethionine, S-adenosylhomocysteine and serum level of folate in 100 elderly type 2 diabetic patients with and without mild cognitive impairment. S-adenosylmethionine/S-adenosylhomocysteine ratio was used to reflect the methylation potential. Patients with mild cognitive impairment had significantly lower levels of S-adenosylmethionine, folate and S-adenosylmethionine/S-adenosylhomocysteineratios. Furthermore, logistic regression analysis indicated the plasma S-adenosylmethionine, S-adenosylmethionine/S-adenosylhomocysteine ratio and serum folate (OR, 0.96, 0.698, 0.72, respectively; p<0.05) were negatively associated with risk of mild cognitive impairment, even after adjusting for related covariates. In addition, folate level was positively correlated with S-adenosylmethionine and the S-adenosylmethionine/S-adenosylhomocysteine ratio (r = 0.38, 0.46, respectively; p<0.05) among patients within the middle tertile of folate levels (6.3-9.1 µg/L). These findings indicate mild cognitive impairment is associated with lower levels of S-adenosylmethionine, folate and weakened methylation potential; plasma S-adenosylmethionine and methylation potential may be predicted by serum folate within a suitable range of folate concentrations in diabetic patients.