NADC34-like porcine reproductive and respiratory syndrome virus(PRRSV),which first appeared in China in 2017,is currently one of the main epidemic strains in China.In this study,we found that a new variant of NADC34-l...NADC34-like porcine reproductive and respiratory syndrome virus(PRRSV),which first appeared in China in 2017,is currently one of the main epidemic strains in China.In this study,we found that a new variant of NADC34-like PRRSV evolved,named the L1A variant.The phylogenetics,epidemic status,and pathogenicity of the LA variants were subsequently comprehensively evaluated.Based on the results of the ORF5 phylogenetic analysis,the L1A variants were classified as NADC34-like PPRSV.All the strains had the same discontinuous 131-aa deletion in the NSP2 region(similar to that in the NADC30).Recombination analysis revealed that the L1A variants were recombinant viruses that contained an NADC30-like PRRSV skeleton,a nonstructural protein-encoding gene region obtained in part from JXA1-like PRRSV and a ORF2-ORF6 gene region partly obtained from NADC34-like PRRSV and that exhibited similar recombination patterns.We successfully isolated the L1A variant TZJ2756 from PAMs and Marc-145 cells.In animal experiments,TZJ2756 exhibited moderate pathogenicity in piglets,causing obvious clinical symptoms,namely,persistent fever,significantly reduced body weight,interstitial edema and severe interstitial pneumonia in the lungs,and prolonged high-load viremia.L1A variants have been detected in at least 12 provinces in China and share many similar epidemiological characteristics with the American L1C variant.This research will enhance our understanding of the prevalence of L1A variants and furnish valuable data for the ongoing monitoring of NADC34-like PRRSV in China.展开更多
Oral immunization is an alternative or supplementary approach that can significantly improve dog vaccination coverage,especially for free-roaming dogs.Safe and effective oral rabies vaccines for dogs are still being s...Oral immunization is an alternative or supplementary approach that can significantly improve dog vaccination coverage,especially for free-roaming dogs.Safe and effective oral rabies vaccines for dogs are still being sought.In our previous studies,we generated a genetically modified rabies virus(RABV) ERA strain,rERAG_(333E),containing a mutation from arginine(Arg,R) to glutamic acid(Glu,E) at residue 333 of the G protein(G_(333E)).Our previous results demonstrated that rERAG_(333E) was safe for adult mice and dogs,and oral vaccination with rERAG_(333E) induced a strong and long-lasting protective immune response in dogs.Here,we further investigated the safety and immunogenicity of rERAG_(333E) in nontarget species,including suckling mice,rhesus monkeys,foxes,raccoon dogs,piglets,goats,and sheep.Suckling mice studies demonstrated that the G_(333E) mutation significantly reduced the virulence of the ERA strain.All of the suckling mice aged 10 days and above survived and showed no apparent signs of disease after intracerebral inoculation with rERAG_(333E).Animal studies demonstrated that rERAG_(333E) was safe in rhesus monkeys,foxes,raccoon dogs,piglets,goats,and sheep.None of those animals inoculated orally with 10 times the intended field dose of rERAG_(333E) showed abnormal clinical signs before and after the booster immunization with Rabvac 3,an inactivated rabies vaccine.Meanwhile,oral inoculation with rERAG_(333E) induced strong neutralizing antibody(NA) responses to RABV in rhesus monkeys,foxes,raccoon dogs,and piglets.These results demonstrated that rERAG_(333E) has the potential to serve as a safe oral rabies vaccine for dogs.展开更多
Background The decline in reproductive performance of aged hens is mainly attributed to oxidative damage in reproductive organs,hepatic lipid metabolism disorders,and intestinal microbiota dysbiosis.Glycyrrhizin(GL)ha...Background The decline in reproductive performance of aged hens is mainly attributed to oxidative damage in reproductive organs,hepatic lipid metabolism disorders,and intestinal microbiota dysbiosis.Glycyrrhizin(GL)has been proven to enhance antioxidant capacity,regulate lipid metabolism and gut microbiota in mammals,but its efficacy in hens remains unclear.Hence,this study aimed to investigate whether dietary GL supplementation improves reproductive performance in hens during the late laying stage by modulating intestinal microbiota composition,hepatic lipid metabolism and ovarian antioxidant status.Results Dietary supplementation with 100 mg/kg GL significantly improved the egg production rate,egg quality,and hatching rate in aged breeder hens(P<0.05).GL supplementation also increased the serum levels of HDLC,TP and ALB,and enhanced the antioxidant capacity in both serum and ovary(P<0.05).In addition,dietary GL elevated the serum progesterone(P4)levels by enhancing the transcription level of steroid synthesis key enzymes(CYP11A1 and 3β-HSD)in the ovary(P<0.05).Dietary GL also promoted the synthesis and transport of vitellogenin(VTG)by upregulating the VTG-Ⅱ(P<0.05)and APOV1(P=0.077)expression levels in the liver,thereby increasing the number of grade follicles and small yellow follicles.Moreover,dietary GL enhanced hepatic fatty acidβ-oxidation by upregulating PPARαand CPT-I(P<0.05),and downregulating ACC expression levels(P<0.05).In agreement,liver metabolomics analysis revealed that dietary GL supplementation significantly altered hepatic metabolism,with 389 differentially identified metabolites(P<0.05).The key metabolites(e.g.,taurocholic acid,tauroursodeoxycholic acid,nicotinuric acid,glycodeoxycholic acid(hydrate))were identified,and they were mainly functionally enriched in betaalanine metabolism nicotinate,taurine and hypotaurine metabolism(P<0.05).Finally,16S rRNA gene sequencing revealed that dietary GL reversed age-induced changes in gut microbiota composition,characterized by a significant increase in Lactobacillus abundance and a decrease in Bacteroides(P<0.05).Conclusions These results collectively demonstrate that dietary supplementation with 100 mg/kg GL improved reproductive performance by reversing age-induced changes in gut microbiota,enhancing hepatic vitellogenin synthesis,and ameliorating ovarian function in aged breeder hens.This study suggests that dietary GL is a potential strategy to improve reproductive performance in broiler breeder hens during the late laying period.展开更多
Potency is one of the most important indexes of inactivated vaccines.A number of methods have been established to assay the potency,of which the NIH test and single-dose mouse protection test are the "prescribed ...Potency is one of the most important indexes of inactivated vaccines.A number of methods have been established to assay the potency,of which the NIH test and single-dose mouse protection test are the "prescribed methods".Here,we report a method to semi-quantitatively assay the potency of an inactivated rabies vaccine,which uses fewer animals and takes less time to complete.Depending on the quality requirements of a vaccine(e.g.minimum potency),a rabies reference vaccine is,for example,diluted to the minimum potency,and 50 μL of the dilution is taken to inoculate 10 mice.The same amount of the test rabies vaccine is inoculated into another 10 mice.After two weeks,all mice are bled and serum samples are assayed for viral neutralizing antibody by the fluorescent antibody virus neutralization(FAVN) test.By comparing the median and interquartile range of antibody titers of the reference vaccine with those of the test vaccine,the test vaccine potency can be semi-quantitatively judged as to whether it is in accord with the required quality.The reliability of this method was also confirmed in dogs.The procedure can be recommended for batch potency testing during inactivated rabies vaccine production.展开更多
Thousands of tons of pharmaceutically active substances are used in veterinary medicines in intensive livestock and poultry production, but most of the drugs are poorly absorbed by animals and excreted with the animal...Thousands of tons of pharmaceutically active substances are used in veterinary medicines in intensive livestock and poultry production, but most of the drugs are poorly absorbed by animals and excreted with the animal feces. The veterinary medicines can cause various kinds of harmful impact to the environment. Now the relevant research has been a hot all over the world. With the feces excreted to the environment, the veterinary medicines can be accumulated in the soil and water, and produce all sorts of reaction. Some medicines can cause toxic effect to animals, plants and microorganisms. The article summarized the residue, the environmental impact, the transformation and the development direction of the veterinary medicine in the environment to supply frame of reference for further research.展开更多
This study was conducted to evaluate the incidence of avian coccidiosis and its associated various risk factors such as age,type of birds and season in a private veterinary clinic in Bukuru,Plateau State Ngeria.A tota...This study was conducted to evaluate the incidence of avian coccidiosis and its associated various risk factors such as age,type of birds and season in a private veterinary clinic in Bukuru,Plateau State Ngeria.A total of 9406 cases during 2013–2017 were analysed and 1556 of them were positive for coccidiosis.There are several reports on the prevalence of avian coccidiosis by previous researchers;however,in this study we evaluated the prevalence of avian coccidiosis in the study area and its economic impacts.Total prevalence of 12.14%in 2013,18.78%in 2014,18.21%in 2015,16.82%in 2016 and 19.07%in 2017 were reported.An overall prevalence of 85.02%was recorded.The average prevalence of coccidiosis based on this five years study is 17%.The association between coccidiosis and age of the birds was determined and age 5-8 weeks becomes most effective period with wet season having high percentage prevalence of coccidiosis.Based on the type of birds,coccidiosis is prevalence almost in equal proportion in both broilers and layers.The losses caused by avian coccidiosis could be both direct and indirect components which may include the cost of control measures,inadequate good hygiene practices,production losses and lack of prophylaxis treatment.The control of avian coccidiosis can be achieved through good sanitary measures by avoiding water spillage on the pen floor,overcrowded stocking density,the use of prophylaxis-anticoccidials and proper good vaccination practices.展开更多
Background:Fruits of Indian gooseberry or Amla or Aonla(Phyllanthus emblica)are important ingredients in many Ayurvedic medicines,but little is known about its leaves.Methods:Different extracts and crude alkaloids of ...Background:Fruits of Indian gooseberry or Amla or Aonla(Phyllanthus emblica)are important ingredients in many Ayurvedic medicines,but little is known about its leaves.Methods:Different extracts and crude alkaloids of P.emblica leaves were evaluated for their antimicrobial activity against clinically important microbes using agar well diffusion assay.The antimicrobial activity of methanolic extract(ME)of P.emblica leaves was also compared with similarly prepared methanolic extracts from leaves of Yellow Kaner(Cascabela peruviana),Parijaat or Harsingar(Nyctanthes arbor-tristis),Custard apple(Annona squamosa),Garlic vine(Mansoa alliacea),Shami plant(Prosopis cineraria),Madar(Calotropis gigantea),and Bael(Aegle marmelos).Results:The ME of leaves of P.emblica was the most potent preparation against bacteria and yeast.Of the 338 strains of microbes belonging to 100 species(96 bacteria and four Candida species),the ME of P.emblica inhibited the growth of 300 strains.A total of 84.62%,96.39%,and 100%of 221 G−bacteria,111 G+bacteria,and 6 Candida species strains,respectively,were inhibited by ME of P.emblica leaves at≤36 mg/well.The aqueous extract of P.emblica leaves also inhibited a similar number of bacterial strains,but at higher concentrations,while the ether extract could inhibit only staphylococci.The alkaloid from P.emblica leaves and the ME from leaves of other plants had insignificant antimicrobial activity at similar≤36 mg/well concentration.Conclusion:The study concluded that the ME of P.emblica leaves may be a useful source of a potent,wide-spectrum antimicrobial substance(s).展开更多
Background:Achromobacter xylosoxidans(A.xylosoxidans)subspecies strains are known to be opportunistic environmental inhabitants.Among the two species,A.xylosoxidans ssp.xylosoxidans is more commonly reported cause of ...Background:Achromobacter xylosoxidans(A.xylosoxidans)subspecies strains are known to be opportunistic environmental inhabitants.Among the two species,A.xylosoxidans ssp.xylosoxidans is more commonly reported cause of nosocomial infections colonizing the hospital environment and medical devices,while A.xylosoxidans ssp.denitrificans(AD)strains are widely distributed in the abiotic environment.The present retrospective observational study was aimed at understanding the occurrence of AD infections in the Bareilly region,and to look into the effective herbal and conventional antimicrobial resistance profile of the strains identified at the laboratory.Methods:The present retrospective study analysed Clinical Microbiology laboratory data of Indian veterinary research Institute.The data for the last 14 years(2011-2024)was retrieved,tabulated and analysed using MS Excel program to determine significance of occurrence,and variation in antimicrobial resistance of the strains isolated from different sources usingχ2 and odds ratio analysis.Results:The study revealed that AD was detectable as a potential pathogen not only from environmental samples but also from 51 clinical cases(either as pure culture or mixed infection),and also from healthy humans and animals.The pathogen was most commonly associated with deaths in animals and birds due to septicaemia and was isolated is single pathogen from blood samples.It was also detected as single pathogen from cases of abortions,metritis,and urinary tract infections.However,from cases of haemorrhagic enteritis,diarrhoea,mastitis,wound infections,pyoderma and abscesses,and middle ear infections AD was isolated in association of one or more potentially pathogenic bacteria.Of the 80 isolates in the study,68 had multiple drug resistance,and 21 produced metallo-β-lactamases responsible for resistance against most of theβ-lactam antibiotics,including cephalosporins and carbapenems.The most effective antibiotic was gentamicin,inhibiting 90.67%of the isolates,followed by tigecycline(85.00%),ciprofloxacin(80.77%),piperacillin tazobactam(80.65%);other antibiotics were effective against less than 80%of the isolates.Among the herbal antimicrobials,cinnamaldehyde,cinnamon oil,carvacrol,and ajowan oil inhibited 98.41%,85.07%,85.00%,and 83.75%of the isolates,respectively.Conclusion:The study concluded that in the Bareilly region in India,multiple-drug-resistance AD may be an emerging pathogen prevalent in environment and apparently healthy animals.More studies are warranted to understand the AD strains at molecular level to understand their zoonotic potential and circulation in the environment.展开更多
The Salmonella pathogenicity islands(SPIs) play crucial roles in the progression of Salmonella infection. In this study, we constructed an improved λ Red homologous recombination system to prepare single and triple d...The Salmonella pathogenicity islands(SPIs) play crucial roles in the progression of Salmonella infection. In this study, we constructed an improved λ Red homologous recombination system to prepare single and triple deletion mutants of 3 prominent SPIs(SPI-1, 2, and 3), aiming at the impact of deletion on morphology, carbon source metabolism, adhesion and invasion capacity, in vivo colonization, and immune efficacy in chicks. Our examination revealed that the surface of the single deletion mutants(SM6ΔSPI1, ΔSPI2, and ΔSPI3) exhibited a more rugged texture and appeared to be enveloped in a layer of transparent colloid, whereas the morphology of the triple deletion mutant(SM6ΔSPI1&2&3) remained unaltered when compared to the parent strain. The carbon metabolic spectrum of the SPI mutants underwent profound alterations, with a notable and statistically significant modification observed in 30 out of 95 carbon sources, primarily carbohydrates(17 out of 30). Furthermore, the adhesion capacity of the 4 mutants to Caco-2 cells was significantly reduced when compared to that of the parent strain. Moreover,the invasion capacity of mutants SM6ΔSPI1 and SM6ΔSPI1&2&3 exhibited a substantial decrease, while it was enhanced to varying degrees for SM6ΔSPI3 and SM6ΔSPI2. Importantly, none of the 4 mutants induced any clinical symptoms in the chicks. However, they did transiently colonize the spleen and liver. Notably, the SM6ΔSPI1&2&3mutant was rapidly cleared from both the spleen and liver within 8 days post-infection and no notable pathological changes were observed in the organs. Additionally, when challenged, the mutants immunized groups displayed a significant increase in antibody levels and alterations in the CD3+CD4+ and CD3+CD8+ subpopulations, and the levels of IL-4 and IFN-γ cytokines in the SM6ΔSPI1&2&3 immunized chicken serum surpassed those of other groups.In summary, the successful construction of the 4 SPI mutants lays the groundwork for further exploration into the pathogenic(including metabolic) mechanisms of SPIs and the development of safe and effective live attenuated Salmonella vaccines or carriers.展开更多
The inappropriate use of cephalosporins lead to the occurrence and global spread of bacteria resistant to these antimicrobials.In this study,we isolated four Escherichia albertii strains from broilers in eastern China...The inappropriate use of cephalosporins lead to the occurrence and global spread of bacteria resistant to these antimicrobials.In this study,we isolated four Escherichia albertii strains from broilers in eastern China.The antimicrobial susceptibility and genomic characterization of these E.albertii isolates were determined.Our results revealed that these four E.albertii isolates exhibited resistance to tetracyclines,chloramphenicol,β-lactams,aminoglycosides,polymyxin B,sulfonamides,quinolones,and other antimicrobials.Among them,EA04 isolate was multidrug resistant and harbored extended-spectrumβ-lactamases(ESBL)genes blaCTX-Mand blaTEM.Whole genome sequencing and core-genome multilocus sequence typing(cgMLST)based on all ST4638 E.albertii for EA04 inferred highly probable epidemiological links between selected human isolates.Additionally,the ESBL genes blaTEM-141and blaCTX-M-55were coexistent in an approximately 75 kb Inc FII plasmid pEA04.2 in EA04.Comparative analysis indicated that genes blaTEM-141and blaCTX-M-55were located in IS15-blaCTX-M-55-wbu C-blaTEM-141-IS26 region,which similar structures were identified in various bacteria.Furthermore,the plasmid pEA04.2 could be transferable to E.coli EC600 and lead to the resistance to third-generation cephalosporins.These results suggested that chicken potentially serve as a reservoir for multidrug resistant E.albertii,which increases the risk of horizontal transfer of antimicrobial resistance between humans,animals and environment.展开更多
Salmonella enterica serovar Typhimurium,the causative agent of gastroenteritis,is one of the most successful intracellular pathogens.Although certain host factors for Salmonella infection have been unveiled,the factor...Salmonella enterica serovar Typhimurium,the causative agent of gastroenteritis,is one of the most successful intracellular pathogens.Although certain host factors for Salmonella infection have been unveiled,the factors mediating Salmonella entry,particularly the invasion process,remain obscure.Here,we have unearthed β2 integrin,a crucial member of the integrin family,as an important host factor facilitating Salmonella invasion.It is demonstrated that overexpression of β2 integrin promotes Salmonella invasion,while the knockdown of β2 integrin significantly diminishes the extent of invasion.Moreover,Salmonella exhibits specific binding affinity towards β2 integrin,and the block of β2 integrin on cell surface substantially reduces the infection of cells in vitro.The ectodomain soluble protein of β2 integrin neutralized Salmonella infection both in cells(in vitro)and in mice(in vivo).Additionally,Salmonella protein YrbD directly interacts with β2 integrin to facilitate its invasion.To our knowledge,this study showed for the first time that the protein YrbD mediates Salmonella adhesion and internalization into host cells by interacting with β2 integrin.These findings not only broaden our understanding of the mechanisms underlying Salmonella entry,but also identify a prospective target for therapeutic control.展开更多
As an emerging genotype,the G9 genotype rotaviruses(RVs)are widespread among humans and pigs,and have been reported in many countries and regions in the recent years.Moreover,porcine G9 strains could cross the intersp...As an emerging genotype,the G9 genotype rotaviruses(RVs)are widespread among humans and pigs,and have been reported in many countries and regions in the recent years.Moreover,porcine G9 strains could cross the interspecies barrier to infect human.To investigate the epidemic trends of porcine G9 strains as well as the cross-immunoreactivity among different isolates,an epidemiological investigation about porcine G9 genotype RVs(PoRVs)was performed during the period 2020-2023 in multiple provinces of China.A total of nine representative strains were identified.The phylogenetic analysis based on viral VP7 gene showed that these strains mainly clustered with lineages Ⅲ and Ⅵ,which revealed the predominant G9 PoRVs in China.Moreover,a new lineage,lineage Ⅶ,was identified,and strains of this lineage were found to be circulating in Guangdong and Taiwan.Except lineages Ⅰ and Ⅳ,some isolates from other lineages could co-circulate in pigs and humans.Three G9 strains,namely 923H,923E,and 923X,which belonged to the largest sub-lineage Ⅲ,were isolated.Then,the significant cross-reactivity was observed among strains of the same or different lineages.This study is the first to systematically investigate the genetic and immunogenetic characteristics of porcine G9 genotype rotavirus in China,as well as the potential cross-species transmission between pigs and humans,providing a valuable direction for the effective prevention of porcine rotavirus.展开更多
Dear editor,As of 2023,the domestic cat population in China reached 65 million,surpassing dogs to become the most numerous companion animal in the country.Feline calicivirus(FCV)infection,one of the three most prevale...Dear editor,As of 2023,the domestic cat population in China reached 65 million,surpassing dogs to become the most numerous companion animal in the country.Feline calicivirus(FCV)infection,one of the three most prevalent infectious diseases in cats,poses a severe threat to feline health.FCV,classified under the Caliciviridae family(genus Vesivirus).展开更多
African swine fever(ASF)is an acute,hemorrhagic,and highly contagious disease in pigs caused by the African swine fever virus(ASFV).Our previous studies have demonstrated that deletion of the MGF360-9L gene weakens AS...African swine fever(ASF)is an acute,hemorrhagic,and highly contagious disease in pigs caused by the African swine fever virus(ASFV).Our previous studies have demonstrated that deletion of the MGF360-9L gene weakens ASFV virulence in pigs,yet the underlying mechanism remains unclear.To investigate the mechanism of MGF360-9L regulating ASFV pathogenicity,the relationship between MGF360-9L and host proteins was identified by mass spectrometry.We found that host protein DEAD-box helicase 20(DDX20)interacted with and colocalized with MGF360-9L.Overexpression of DDX20 inhibited ASFV replication,whereas knockdown of DDX20 had the opposite effects.Moreover,DDX20 inhibited ASFV replication by promoting the activation of type I interferon signaling.Surprisingly,DDX20 was gradually degraded following ASFV infection.Mechanistically,MGF360-9L promoted the autophagic degradation of DDX20 by recruiting autophagy-related protein Ras-related protein Rab-1A(Rab1A).Silencing Rab1A suppressed ASFV replication,while overexpression of Rab1A exhibited the opposite effects.Furthermore,Rab1A,MGF360-9L and DDX20 could form a complex to facilitate the degradation of DDX20.Knockdown of Rab1A impaired MGF360-9L-mediated degradation of DDX20 during ASFV infection.In summary,our study demonstrates that MGF360-9L targets DDX20 for autophagy degradation to antagonize its antiviral function and facilitate ASFV replication.This finding broadens our understanding of the regulatory network between ASFV and its host,and provides new insights into the pathogenesis and immune evasion mechanisms of ASFV.展开更多
Background:Although many sugars are known antibacterial in higher concentrations(>50%W/V)and a few at low concentrations too(≤1 mg/mL),most of the studies are limited to only a few reference isolates,therefore no ...Background:Although many sugars are known antibacterial in higher concentrations(>50%W/V)and a few at low concentrations too(≤1 mg/mL),most of the studies are limited to only a few reference isolates,therefore no concrete conclusion can be drawn.Methods:This study evaluated the antimicrobial potential of 19 sugars against 8000 isolates of bacteria belonging to 46 genera and also against 30 reference strains of microbes of 14 different species.To determine susceptibility to sugars,a sugar-disc(1 mg)diffusion assay was performed on Mueller Hinton agar using the same method used for antimicrobial susceptibility of microbial strains.Results:In the study,of 3,336 isolates of Gram-positive bacteria 147(4.35%)were susceptible to one or more sugars but only 16(0.37%)of the 4644 isolates of Gram-negative bacteria were susceptible to one or other sugar.Gram-positive bacteria were significantly more often susceptible to one or more sugars than isolates of Gram-negative bacteria(OR 13.33,CI99,6.74–26.37).A total of 163 test-isolates(2.04%)but none of the reference strains were sugar susceptible.Most of the isolates susceptible to sugars(135 of 2,295)were members of the Bacillaceae(36/679)and Micrococcaceae(99/1,616)family.However,out of 5,705 isolates belonging to other bacterial families,only 28 isolates(0.49%)were susceptible to one or more sugars.The most effective to least effective sugars as antibacterial were mannose,inositol,mannitol,sucrose,raffinose,ribose,xylose,trehalose,dulcitol,maltose,lactose,inulin,salicin,melibiose,sorbitol,adonitol,arabinose,glucose,and esculin,inhibiting 69,58,23,14,11,10,10,7,7,7,6,6,5,5,5,5,2,1,and 1 of the test-isolates,respectively.Conclusion:The results are still intriguing in determining the utility of sugar susceptibility of different bacteria and are still beyond making any conclusion for their therapeutic utility.However,the study can be concluded that Gram-positive bacteria are generally more susceptible to lower concentrations of different sugars than Gram-negative bacteria,and various sugars have variable selectivity in their antibacterial effect on multiple types of bacteria.展开更多
Avian metapneumovirus(aMPV),a paramyxovirus,causes acute respiratory diseases in turkeys and swollen head syndrome in chickens.This study established a reverse genetics system for aMPV subtype B LN16-A strain based on...Avian metapneumovirus(aMPV),a paramyxovirus,causes acute respiratory diseases in turkeys and swollen head syndrome in chickens.This study established a reverse genetics system for aMPV subtype B LN16-A strain based on T7 RNA polymerase.Full-length cDNA of the LN16-A strain was constructed by assembling 5 cDNA fragments between the T7 promoter and hepatitis delta virus ribozyme.Transfection of this plasmid,along with the supporting plasmids encoding the N,P,M2-1,and L proteins of LN16-A into BSR-T7/5 cells,resulted in the recovery of aMPV subtype B.To identify an effective insertion site,the enhanced green fluorescent protein(EGFP)gene was inserted into different sites of the LN16-A genome to generate recombinant LN16-As.The results showed that the expression levels of EGFP at the site between the G and L genes of LN16-A were significantly higher than those at the other two sites(between the leader and N genes or replacing the SH gene).To verify the availability of the site between G and L for foreign gene expression,the VP2 gene of very virulent infectious bursal disease virus(vvIBDV)was inserted into this site,and recombinant LN16-A(rLN16A-vvVP2)was successfully rescued.Single immunization of specificpathogen-free chickens with rLN16A-vvVP2 induced high levels of neutralizing antibodies and provided 100%protection against the virulent aMPV subtype B and vvIBDV.Establishing a reverse genetics system here provides an important foundation for understanding aMPV pathogenesis and developing novel vector vaccines.展开更多
Infectious bursal disease(IBD)is an acute,highly contagious disease that affects chicks(Müller et al.2003).IBD mainly damages the immune organs of chicks,especially the central immune organ,causing immune suppres...Infectious bursal disease(IBD)is an acute,highly contagious disease that affects chicks(Müller et al.2003).IBD mainly damages the immune organs of chicks,especially the central immune organ,causing immune suppression in diseased chicks(Muller et al.2012).The pathogenic infectious bursal disease virus(IBDV)is a member of the Avira virus genus in the Birnaviridae family.(Harkness et al.1975;Dobos et al.1979;Müller et al.1979).IBDV is prevalent worldwide,causing serious economic losses to the global poultry industry.Currently,vaccination remains the most cost-effective way to prevent IBDV.展开更多
Influenza A viruses(IAVs)are single-stranded negative-sense RNA viruses that continually challenge animal and human health.In IAV-infected cells,host RNA-binding proteins play key roles in the life cycle of IAV by dir...Influenza A viruses(IAVs)are single-stranded negative-sense RNA viruses that continually challenge animal and human health.In IAV-infected cells,host RNA-binding proteins play key roles in the life cycle of IAV by directly binding to viral RNA.Here,we examined the role of the host RNA-binding protein nucleophosmin-1(NPM1)in IAV replication.We found that,as a nucleolar phosphoprotein,NPM1 directly binds to viral RNA(vRNA)and inhibits the replication of various subtypes of IAV.NPM1 binding to vRNA competitively reduces the assembly of the viral ribonucleoprotein complex and the viral polymerase activity,thereby reducing the generation of progeny viral RNA and virions.The RNA-binding activity of NPM1,with the key residues T199,T219,T234,and T237,is essential for its anti-influenza function.Taken together,our findings demonstrate that NPM1 acts as an RNA-binding protein and interacts with IAV vRNA to suppress viral replication.展开更多
In this study,we developed a highly sensitive enzyme-linked immunosorbent assay(ELISA)using newly produced monoclonal antibodies(mAbs)for detecting horse/donkey IL-1βin cell culture medium and serum samples.The mAbs ...In this study,we developed a highly sensitive enzyme-linked immunosorbent assay(ELISA)using newly produced monoclonal antibodies(mAbs)for detecting horse/donkey IL-1βin cell culture medium and serum samples.The mAbs were generated via the use of a KLH-conjugated peptide and purified equine IL-1βprotein as separate immunogens.Notably,the generated mAbs(3G8 and 5G3)demonstrated no cross-reactivity with other major inflammatory mediators,including IL-1α,IL-1Ra,TNF-α,and SAA.The IL-1βassay,which is based on the screened mAbs,exhibits a detection range of 200-10,000 pg/mL,meeting clinical detection requirements.The coefficients of variation for the repeatability and reproducibility of the assay were both less than 5%,indicating an acceptable level of variation.Subsequently,84 equine and 24 asinine serum samples were collected,and the IL-1βconcentration was measured with both our assay and a commercial kit in parallel.Our results revealed no significant difference between the in-house and commercial ELISA kits for the detection of IL-1βconcentrations in horse sera.Moreover,our ELISA method demonstrated superior sensitivity for IL-1βdetection in donkey samples compared to existing commercial assays.These findings suggest that the newly developed ELISA provides a reliable analytical method for detecting IL-1βin both equine and asinine samples.展开更多
Objective:The objective of this study was to determine the level of methotrexate(MTX)toxicity in the intestines of mice and to evaluate the protective effect of probiotics composed of Streptococcus,Bifidobacterium,and...Objective:The objective of this study was to determine the level of methotrexate(MTX)toxicity in the intestines of mice and to evaluate the protective effect of probiotics composed of Streptococcus,Bifidobacterium,and Lactobacillus species on intestinal cells during MTX treatment.Methods:Mice were divided into three groups:control,MTX group(received MTX injections),and MTX+probiotics group(received MTX injections along with a diet containing probiotics).Morphological and histological changes,the level of mitochondrial DNA(mtDNA)damage,the level of lipid peroxidation products,and gene expression in the mice’s small intestine were assessed.Results:We demonstrated that intraperitoneal MTX injections significantly increased mtDNA damage in the liver(p<0.001),small intestine(p<0.001),and blood of mice(p<0.01).MTX elevated the quantity of lipid peroxidation products in the liver and small intestine,indicating its strong prooxidative properties.MTX induced structural changes in the mice’s intestines,characterized by leukocytic infiltration of tissues.Probiotic therapy in mice partially mitigated the morphological and histological changes in the small intestine induced by MTX,reduced oxidative stress,and promoted increased expression of quinone oxidoreductase 1(Nqo1),which participates in both cell protection against oxidative stress and drug/xenobiotic detoxification.Probiotics prevented the upregulation of the proinflammatory cytokine IL-1b in the small intestine and induced increased expression of genes associated with the Nuclear factor erythroid 2-related factor 2/Antioxidant response element(Nrf2/ARE)pathway,an important mechanism of cell protection.Conclusions:Probiotics can be considered an effective approach to reducing the toxicity of MTX during psoriasis or cancer treatment.展开更多
基金supported by grants from the National Natural Science Foundation of China(32172890 and 32002315)the National Key Research and Development Program of China(2022YFF0711004)+3 种基金the Natural Science Foundation of Heilongjiang Province,China(YQ2022C042)the State Key Laboratory of Veterinary Biotechnology Foundation of China(SKLVBF202208)the Postdoctoral Fellowship Program of CPSF,China(GZC20233062)the National Center of Technology Innovation for Pigs,China(NCTIP-XD/C09)。
文摘NADC34-like porcine reproductive and respiratory syndrome virus(PRRSV),which first appeared in China in 2017,is currently one of the main epidemic strains in China.In this study,we found that a new variant of NADC34-like PRRSV evolved,named the L1A variant.The phylogenetics,epidemic status,and pathogenicity of the LA variants were subsequently comprehensively evaluated.Based on the results of the ORF5 phylogenetic analysis,the L1A variants were classified as NADC34-like PPRSV.All the strains had the same discontinuous 131-aa deletion in the NSP2 region(similar to that in the NADC30).Recombination analysis revealed that the L1A variants were recombinant viruses that contained an NADC30-like PRRSV skeleton,a nonstructural protein-encoding gene region obtained in part from JXA1-like PRRSV and a ORF2-ORF6 gene region partly obtained from NADC34-like PRRSV and that exhibited similar recombination patterns.We successfully isolated the L1A variant TZJ2756 from PAMs and Marc-145 cells.In animal experiments,TZJ2756 exhibited moderate pathogenicity in piglets,causing obvious clinical symptoms,namely,persistent fever,significantly reduced body weight,interstitial edema and severe interstitial pneumonia in the lungs,and prolonged high-load viremia.L1A variants have been detected in at least 12 provinces in China and share many similar epidemiological characteristics with the American L1C variant.This research will enhance our understanding of the prevalence of L1A variants and furnish valuable data for the ongoing monitoring of NADC34-like PRRSV in China.
基金supported by the Natural Science Foundation of Heilongjiang Province,China (YQ2022C040)。
文摘Oral immunization is an alternative or supplementary approach that can significantly improve dog vaccination coverage,especially for free-roaming dogs.Safe and effective oral rabies vaccines for dogs are still being sought.In our previous studies,we generated a genetically modified rabies virus(RABV) ERA strain,rERAG_(333E),containing a mutation from arginine(Arg,R) to glutamic acid(Glu,E) at residue 333 of the G protein(G_(333E)).Our previous results demonstrated that rERAG_(333E) was safe for adult mice and dogs,and oral vaccination with rERAG_(333E) induced a strong and long-lasting protective immune response in dogs.Here,we further investigated the safety and immunogenicity of rERAG_(333E) in nontarget species,including suckling mice,rhesus monkeys,foxes,raccoon dogs,piglets,goats,and sheep.Suckling mice studies demonstrated that the G_(333E) mutation significantly reduced the virulence of the ERA strain.All of the suckling mice aged 10 days and above survived and showed no apparent signs of disease after intracerebral inoculation with rERAG_(333E).Animal studies demonstrated that rERAG_(333E) was safe in rhesus monkeys,foxes,raccoon dogs,piglets,goats,and sheep.None of those animals inoculated orally with 10 times the intended field dose of rERAG_(333E) showed abnormal clinical signs before and after the booster immunization with Rabvac 3,an inactivated rabies vaccine.Meanwhile,oral inoculation with rERAG_(333E) induced strong neutralizing antibody(NA) responses to RABV in rhesus monkeys,foxes,raccoon dogs,and piglets.These results demonstrated that rERAG_(333E) has the potential to serve as a safe oral rabies vaccine for dogs.
基金supported and funded by the National Key Research and Development Program of China(2023YFD1300801)the Agricultural Science and Technology Innovation Program in Chinese Academy of Agricultural Sciences(ASTIP-IAS-08)。
文摘Background The decline in reproductive performance of aged hens is mainly attributed to oxidative damage in reproductive organs,hepatic lipid metabolism disorders,and intestinal microbiota dysbiosis.Glycyrrhizin(GL)has been proven to enhance antioxidant capacity,regulate lipid metabolism and gut microbiota in mammals,but its efficacy in hens remains unclear.Hence,this study aimed to investigate whether dietary GL supplementation improves reproductive performance in hens during the late laying stage by modulating intestinal microbiota composition,hepatic lipid metabolism and ovarian antioxidant status.Results Dietary supplementation with 100 mg/kg GL significantly improved the egg production rate,egg quality,and hatching rate in aged breeder hens(P<0.05).GL supplementation also increased the serum levels of HDLC,TP and ALB,and enhanced the antioxidant capacity in both serum and ovary(P<0.05).In addition,dietary GL elevated the serum progesterone(P4)levels by enhancing the transcription level of steroid synthesis key enzymes(CYP11A1 and 3β-HSD)in the ovary(P<0.05).Dietary GL also promoted the synthesis and transport of vitellogenin(VTG)by upregulating the VTG-Ⅱ(P<0.05)and APOV1(P=0.077)expression levels in the liver,thereby increasing the number of grade follicles and small yellow follicles.Moreover,dietary GL enhanced hepatic fatty acidβ-oxidation by upregulating PPARαand CPT-I(P<0.05),and downregulating ACC expression levels(P<0.05).In agreement,liver metabolomics analysis revealed that dietary GL supplementation significantly altered hepatic metabolism,with 389 differentially identified metabolites(P<0.05).The key metabolites(e.g.,taurocholic acid,tauroursodeoxycholic acid,nicotinuric acid,glycodeoxycholic acid(hydrate))were identified,and they were mainly functionally enriched in betaalanine metabolism nicotinate,taurine and hypotaurine metabolism(P<0.05).Finally,16S rRNA gene sequencing revealed that dietary GL reversed age-induced changes in gut microbiota composition,characterized by a significant increase in Lactobacillus abundance and a decrease in Bacteroides(P<0.05).Conclusions These results collectively demonstrate that dietary supplementation with 100 mg/kg GL improved reproductive performance by reversing age-induced changes in gut microbiota,enhancing hepatic vitellogenin synthesis,and ameliorating ovarian function in aged breeder hens.This study suggests that dietary GL is a potential strategy to improve reproductive performance in broiler breeder hens during the late laying period.
基金the China National"863"Program(Approval No.2011AA10A212)Special Fund for Agro-Scientific Research in the Public Interest(ApprovalNo.201203056)
文摘Potency is one of the most important indexes of inactivated vaccines.A number of methods have been established to assay the potency,of which the NIH test and single-dose mouse protection test are the "prescribed methods".Here,we report a method to semi-quantitatively assay the potency of an inactivated rabies vaccine,which uses fewer animals and takes less time to complete.Depending on the quality requirements of a vaccine(e.g.minimum potency),a rabies reference vaccine is,for example,diluted to the minimum potency,and 50 μL of the dilution is taken to inoculate 10 mice.The same amount of the test rabies vaccine is inoculated into another 10 mice.After two weeks,all mice are bled and serum samples are assayed for viral neutralizing antibody by the fluorescent antibody virus neutralization(FAVN) test.By comparing the median and interquartile range of antibody titers of the reference vaccine with those of the test vaccine,the test vaccine potency can be semi-quantitatively judged as to whether it is in accord with the required quality.The reliability of this method was also confirmed in dogs.The procedure can be recommended for batch potency testing during inactivated rabies vaccine production.
文摘Thousands of tons of pharmaceutically active substances are used in veterinary medicines in intensive livestock and poultry production, but most of the drugs are poorly absorbed by animals and excreted with the animal feces. The veterinary medicines can cause various kinds of harmful impact to the environment. Now the relevant research has been a hot all over the world. With the feces excreted to the environment, the veterinary medicines can be accumulated in the soil and water, and produce all sorts of reaction. Some medicines can cause toxic effect to animals, plants and microorganisms. The article summarized the residue, the environmental impact, the transformation and the development direction of the veterinary medicine in the environment to supply frame of reference for further research.
文摘This study was conducted to evaluate the incidence of avian coccidiosis and its associated various risk factors such as age,type of birds and season in a private veterinary clinic in Bukuru,Plateau State Ngeria.A total of 9406 cases during 2013–2017 were analysed and 1556 of them were positive for coccidiosis.There are several reports on the prevalence of avian coccidiosis by previous researchers;however,in this study we evaluated the prevalence of avian coccidiosis in the study area and its economic impacts.Total prevalence of 12.14%in 2013,18.78%in 2014,18.21%in 2015,16.82%in 2016 and 19.07%in 2017 were reported.An overall prevalence of 85.02%was recorded.The average prevalence of coccidiosis based on this five years study is 17%.The association between coccidiosis and age of the birds was determined and age 5-8 weeks becomes most effective period with wet season having high percentage prevalence of coccidiosis.Based on the type of birds,coccidiosis is prevalence almost in equal proportion in both broilers and layers.The losses caused by avian coccidiosis could be both direct and indirect components which may include the cost of control measures,inadequate good hygiene practices,production losses and lack of prophylaxis treatment.The control of avian coccidiosis can be achieved through good sanitary measures by avoiding water spillage on the pen floor,overcrowded stocking density,the use of prophylaxis-anticoccidials and proper good vaccination practices.
基金supported by grants from CAAST-ACLH(NAHEP/CAAST/2018-19)of the ICAR-World Bank-funded National Agricultural Higher Education Project(NAHEP).
文摘Background:Fruits of Indian gooseberry or Amla or Aonla(Phyllanthus emblica)are important ingredients in many Ayurvedic medicines,but little is known about its leaves.Methods:Different extracts and crude alkaloids of P.emblica leaves were evaluated for their antimicrobial activity against clinically important microbes using agar well diffusion assay.The antimicrobial activity of methanolic extract(ME)of P.emblica leaves was also compared with similarly prepared methanolic extracts from leaves of Yellow Kaner(Cascabela peruviana),Parijaat or Harsingar(Nyctanthes arbor-tristis),Custard apple(Annona squamosa),Garlic vine(Mansoa alliacea),Shami plant(Prosopis cineraria),Madar(Calotropis gigantea),and Bael(Aegle marmelos).Results:The ME of leaves of P.emblica was the most potent preparation against bacteria and yeast.Of the 338 strains of microbes belonging to 100 species(96 bacteria and four Candida species),the ME of P.emblica inhibited the growth of 300 strains.A total of 84.62%,96.39%,and 100%of 221 G−bacteria,111 G+bacteria,and 6 Candida species strains,respectively,were inhibited by ME of P.emblica leaves at≤36 mg/well.The aqueous extract of P.emblica leaves also inhibited a similar number of bacterial strains,but at higher concentrations,while the ether extract could inhibit only staphylococci.The alkaloid from P.emblica leaves and the ME from leaves of other plants had insignificant antimicrobial activity at similar≤36 mg/well concentration.Conclusion:The study concluded that the ME of P.emblica leaves may be a useful source of a potent,wide-spectrum antimicrobial substance(s).
基金supported by grants from CAAST-ACLH(NAHEP/CAAST/2018-19)of the ICAR-World Bank-funded National Agricultural Higher Education Project(NAHEP).
文摘Background:Achromobacter xylosoxidans(A.xylosoxidans)subspecies strains are known to be opportunistic environmental inhabitants.Among the two species,A.xylosoxidans ssp.xylosoxidans is more commonly reported cause of nosocomial infections colonizing the hospital environment and medical devices,while A.xylosoxidans ssp.denitrificans(AD)strains are widely distributed in the abiotic environment.The present retrospective observational study was aimed at understanding the occurrence of AD infections in the Bareilly region,and to look into the effective herbal and conventional antimicrobial resistance profile of the strains identified at the laboratory.Methods:The present retrospective study analysed Clinical Microbiology laboratory data of Indian veterinary research Institute.The data for the last 14 years(2011-2024)was retrieved,tabulated and analysed using MS Excel program to determine significance of occurrence,and variation in antimicrobial resistance of the strains isolated from different sources usingχ2 and odds ratio analysis.Results:The study revealed that AD was detectable as a potential pathogen not only from environmental samples but also from 51 clinical cases(either as pure culture or mixed infection),and also from healthy humans and animals.The pathogen was most commonly associated with deaths in animals and birds due to septicaemia and was isolated is single pathogen from blood samples.It was also detected as single pathogen from cases of abortions,metritis,and urinary tract infections.However,from cases of haemorrhagic enteritis,diarrhoea,mastitis,wound infections,pyoderma and abscesses,and middle ear infections AD was isolated in association of one or more potentially pathogenic bacteria.Of the 80 isolates in the study,68 had multiple drug resistance,and 21 produced metallo-β-lactamases responsible for resistance against most of theβ-lactam antibiotics,including cephalosporins and carbapenems.The most effective antibiotic was gentamicin,inhibiting 90.67%of the isolates,followed by tigecycline(85.00%),ciprofloxacin(80.77%),piperacillin tazobactam(80.65%);other antibiotics were effective against less than 80%of the isolates.Among the herbal antimicrobials,cinnamaldehyde,cinnamon oil,carvacrol,and ajowan oil inhibited 98.41%,85.07%,85.00%,and 83.75%of the isolates,respectively.Conclusion:The study concluded that in the Bareilly region in India,multiple-drug-resistance AD may be an emerging pathogen prevalent in environment and apparently healthy animals.More studies are warranted to understand the AD strains at molecular level to understand their zoonotic potential and circulation in the environment.
基金supported by the National KeyR&DProgramof China(2022YFF0710500)the National Natural Science Foundation of China(32172853 and 32373013)the Central Public-interest Scientific Institution Basal Research Fund,China(1610302022001).
文摘The Salmonella pathogenicity islands(SPIs) play crucial roles in the progression of Salmonella infection. In this study, we constructed an improved λ Red homologous recombination system to prepare single and triple deletion mutants of 3 prominent SPIs(SPI-1, 2, and 3), aiming at the impact of deletion on morphology, carbon source metabolism, adhesion and invasion capacity, in vivo colonization, and immune efficacy in chicks. Our examination revealed that the surface of the single deletion mutants(SM6ΔSPI1, ΔSPI2, and ΔSPI3) exhibited a more rugged texture and appeared to be enveloped in a layer of transparent colloid, whereas the morphology of the triple deletion mutant(SM6ΔSPI1&2&3) remained unaltered when compared to the parent strain. The carbon metabolic spectrum of the SPI mutants underwent profound alterations, with a notable and statistically significant modification observed in 30 out of 95 carbon sources, primarily carbohydrates(17 out of 30). Furthermore, the adhesion capacity of the 4 mutants to Caco-2 cells was significantly reduced when compared to that of the parent strain. Moreover,the invasion capacity of mutants SM6ΔSPI1 and SM6ΔSPI1&2&3 exhibited a substantial decrease, while it was enhanced to varying degrees for SM6ΔSPI3 and SM6ΔSPI2. Importantly, none of the 4 mutants induced any clinical symptoms in the chicks. However, they did transiently colonize the spleen and liver. Notably, the SM6ΔSPI1&2&3mutant was rapidly cleared from both the spleen and liver within 8 days post-infection and no notable pathological changes were observed in the organs. Additionally, when challenged, the mutants immunized groups displayed a significant increase in antibody levels and alterations in the CD3+CD4+ and CD3+CD8+ subpopulations, and the levels of IL-4 and IFN-γ cytokines in the SM6ΔSPI1&2&3 immunized chicken serum surpassed those of other groups.In summary, the successful construction of the 4 SPI mutants lays the groundwork for further exploration into the pathogenic(including metabolic) mechanisms of SPIs and the development of safe and effective live attenuated Salmonella vaccines or carriers.
基金supported by the National Key Research and Development Program of China(2021YFD1800402)the National Natural Science Foundation of China(32172856,31972654 and 32302881)+1 种基金the Natural Science Foundation of Shanghai,China(22ZR1476100 and 23ZR1476600)the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences(SHVRI-ASTIP-2014-8)。
文摘The inappropriate use of cephalosporins lead to the occurrence and global spread of bacteria resistant to these antimicrobials.In this study,we isolated four Escherichia albertii strains from broilers in eastern China.The antimicrobial susceptibility and genomic characterization of these E.albertii isolates were determined.Our results revealed that these four E.albertii isolates exhibited resistance to tetracyclines,chloramphenicol,β-lactams,aminoglycosides,polymyxin B,sulfonamides,quinolones,and other antimicrobials.Among them,EA04 isolate was multidrug resistant and harbored extended-spectrumβ-lactamases(ESBL)genes blaCTX-Mand blaTEM.Whole genome sequencing and core-genome multilocus sequence typing(cgMLST)based on all ST4638 E.albertii for EA04 inferred highly probable epidemiological links between selected human isolates.Additionally,the ESBL genes blaTEM-141and blaCTX-M-55were coexistent in an approximately 75 kb Inc FII plasmid pEA04.2 in EA04.Comparative analysis indicated that genes blaTEM-141and blaCTX-M-55were located in IS15-blaCTX-M-55-wbu C-blaTEM-141-IS26 region,which similar structures were identified in various bacteria.Furthermore,the plasmid pEA04.2 could be transferable to E.coli EC600 and lead to the resistance to third-generation cephalosporins.These results suggested that chicken potentially serve as a reservoir for multidrug resistant E.albertii,which increases the risk of horizontal transfer of antimicrobial resistance between humans,animals and environment.
基金supported by the National Key R&D Program of China(2022YFF0710500)the the National Natural Science Foundation,China(31802192,32172853 and 32373013)+2 种基金the Natural Science Foundation of Heilongjiang Province of China(C2018070)China Postdoctoral Science Foundation(2017M620076)the Central Public-interest Scientific Institution Basal Research Fund,China(1610302022001)。
文摘Salmonella enterica serovar Typhimurium,the causative agent of gastroenteritis,is one of the most successful intracellular pathogens.Although certain host factors for Salmonella infection have been unveiled,the factors mediating Salmonella entry,particularly the invasion process,remain obscure.Here,we have unearthed β2 integrin,a crucial member of the integrin family,as an important host factor facilitating Salmonella invasion.It is demonstrated that overexpression of β2 integrin promotes Salmonella invasion,while the knockdown of β2 integrin significantly diminishes the extent of invasion.Moreover,Salmonella exhibits specific binding affinity towards β2 integrin,and the block of β2 integrin on cell surface substantially reduces the infection of cells in vitro.The ectodomain soluble protein of β2 integrin neutralized Salmonella infection both in cells(in vitro)and in mice(in vivo).Additionally,Salmonella protein YrbD directly interacts with β2 integrin to facilitate its invasion.To our knowledge,this study showed for the first time that the protein YrbD mediates Salmonella adhesion and internalization into host cells by interacting with β2 integrin.These findings not only broaden our understanding of the mechanisms underlying Salmonella entry,but also identify a prospective target for therapeutic control.
基金supported by the National Natural Science Foundation of China(Grant no.32402927).
文摘As an emerging genotype,the G9 genotype rotaviruses(RVs)are widespread among humans and pigs,and have been reported in many countries and regions in the recent years.Moreover,porcine G9 strains could cross the interspecies barrier to infect human.To investigate the epidemic trends of porcine G9 strains as well as the cross-immunoreactivity among different isolates,an epidemiological investigation about porcine G9 genotype RVs(PoRVs)was performed during the period 2020-2023 in multiple provinces of China.A total of nine representative strains were identified.The phylogenetic analysis based on viral VP7 gene showed that these strains mainly clustered with lineages Ⅲ and Ⅵ,which revealed the predominant G9 PoRVs in China.Moreover,a new lineage,lineage Ⅶ,was identified,and strains of this lineage were found to be circulating in Guangdong and Taiwan.Except lineages Ⅰ and Ⅳ,some isolates from other lineages could co-circulate in pigs and humans.Three G9 strains,namely 923H,923E,and 923X,which belonged to the largest sub-lineage Ⅲ,were isolated.Then,the significant cross-reactivity was observed among strains of the same or different lineages.This study is the first to systematically investigate the genetic and immunogenetic characteristics of porcine G9 genotype rotavirus in China,as well as the potential cross-species transmission between pigs and humans,providing a valuable direction for the effective prevention of porcine rotavirus.
基金supported by grants from the National Key Research and Development Program of China(Grant No.2022YFD1800100)National Natural Science Foundation of China(Grant No.32272982)Natural Science Foundation of Shanghai(Grant No.23ZR1477100).
文摘Dear editor,As of 2023,the domestic cat population in China reached 65 million,surpassing dogs to become the most numerous companion animal in the country.Feline calicivirus(FCV)infection,one of the three most prevalent infectious diseases in cats,poses a severe threat to feline health.FCV,classified under the Caliciviridae family(genus Vesivirus).
基金supported by the grants from the open competition program of top ten critical priorities of Agricultural Science and Technology Innovation for the 14th Five-Year Plan of Guangdong Province(2024KJ14)the Fundamental Research Funds for the Central Universities(lzujbky-2022-ct02)+7 种基金the Project of National Center of Technology Innovation for Pigs(NCTIP-XD/C03)the Youth Innovation Program of the Chinese Academy of Agricultural Sciences(Y2025QC33)the Major Science and Technology Project of Gansu Province(22ZD6NA001 and 22ZD6NA012)the Innovation Program of Chinese Academy of Agricultural Sciences(CAAS-CSLPDCP-2023002 and CAAS-ASTIP-2025-LVRI)the China Postdoctoral Science Foundation(2023M743830)the Earmarked Fund for CARS-35 and CARS-39-13he Fundamental Research Funds for Innovation Team of Gansu Province(23JRRA546,23JRRA548)the Basic Scientific Research Fund of LVRI(1610312021009).
文摘African swine fever(ASF)is an acute,hemorrhagic,and highly contagious disease in pigs caused by the African swine fever virus(ASFV).Our previous studies have demonstrated that deletion of the MGF360-9L gene weakens ASFV virulence in pigs,yet the underlying mechanism remains unclear.To investigate the mechanism of MGF360-9L regulating ASFV pathogenicity,the relationship between MGF360-9L and host proteins was identified by mass spectrometry.We found that host protein DEAD-box helicase 20(DDX20)interacted with and colocalized with MGF360-9L.Overexpression of DDX20 inhibited ASFV replication,whereas knockdown of DDX20 had the opposite effects.Moreover,DDX20 inhibited ASFV replication by promoting the activation of type I interferon signaling.Surprisingly,DDX20 was gradually degraded following ASFV infection.Mechanistically,MGF360-9L promoted the autophagic degradation of DDX20 by recruiting autophagy-related protein Ras-related protein Rab-1A(Rab1A).Silencing Rab1A suppressed ASFV replication,while overexpression of Rab1A exhibited the opposite effects.Furthermore,Rab1A,MGF360-9L and DDX20 could form a complex to facilitate the degradation of DDX20.Knockdown of Rab1A impaired MGF360-9L-mediated degradation of DDX20 during ASFV infection.In summary,our study demonstrates that MGF360-9L targets DDX20 for autophagy degradation to antagonize its antiviral function and facilitate ASFV replication.This finding broadens our understanding of the regulatory network between ASFV and its host,and provides new insights into the pathogenesis and immune evasion mechanisms of ASFV.
基金supported by grants received from CAAST-ACLH(NAHEP/CAAST/2018-19)of ICAR-World Bank-funded National Agricultural Higher Education Project(NAHEP).
文摘Background:Although many sugars are known antibacterial in higher concentrations(>50%W/V)and a few at low concentrations too(≤1 mg/mL),most of the studies are limited to only a few reference isolates,therefore no concrete conclusion can be drawn.Methods:This study evaluated the antimicrobial potential of 19 sugars against 8000 isolates of bacteria belonging to 46 genera and also against 30 reference strains of microbes of 14 different species.To determine susceptibility to sugars,a sugar-disc(1 mg)diffusion assay was performed on Mueller Hinton agar using the same method used for antimicrobial susceptibility of microbial strains.Results:In the study,of 3,336 isolates of Gram-positive bacteria 147(4.35%)were susceptible to one or more sugars but only 16(0.37%)of the 4644 isolates of Gram-negative bacteria were susceptible to one or other sugar.Gram-positive bacteria were significantly more often susceptible to one or more sugars than isolates of Gram-negative bacteria(OR 13.33,CI99,6.74–26.37).A total of 163 test-isolates(2.04%)but none of the reference strains were sugar susceptible.Most of the isolates susceptible to sugars(135 of 2,295)were members of the Bacillaceae(36/679)and Micrococcaceae(99/1,616)family.However,out of 5,705 isolates belonging to other bacterial families,only 28 isolates(0.49%)were susceptible to one or more sugars.The most effective to least effective sugars as antibacterial were mannose,inositol,mannitol,sucrose,raffinose,ribose,xylose,trehalose,dulcitol,maltose,lactose,inulin,salicin,melibiose,sorbitol,adonitol,arabinose,glucose,and esculin,inhibiting 69,58,23,14,11,10,10,7,7,7,6,6,5,5,5,5,2,1,and 1 of the test-isolates,respectively.Conclusion:The results are still intriguing in determining the utility of sugar susceptibility of different bacteria and are still beyond making any conclusion for their therapeutic utility.However,the study can be concluded that Gram-positive bacteria are generally more susceptible to lower concentrations of different sugars than Gram-negative bacteria,and various sugars have variable selectivity in their antibacterial effect on multiple types of bacteria.
基金supported by the grants from the National Key Research and Development Program of China(2022YFD1800604)the China Agriculture Research System(CARS-41)the Heilongjiang Touyan Innovation Team Program,China。
文摘Avian metapneumovirus(aMPV),a paramyxovirus,causes acute respiratory diseases in turkeys and swollen head syndrome in chickens.This study established a reverse genetics system for aMPV subtype B LN16-A strain based on T7 RNA polymerase.Full-length cDNA of the LN16-A strain was constructed by assembling 5 cDNA fragments between the T7 promoter and hepatitis delta virus ribozyme.Transfection of this plasmid,along with the supporting plasmids encoding the N,P,M2-1,and L proteins of LN16-A into BSR-T7/5 cells,resulted in the recovery of aMPV subtype B.To identify an effective insertion site,the enhanced green fluorescent protein(EGFP)gene was inserted into different sites of the LN16-A genome to generate recombinant LN16-As.The results showed that the expression levels of EGFP at the site between the G and L genes of LN16-A were significantly higher than those at the other two sites(between the leader and N genes or replacing the SH gene).To verify the availability of the site between G and L for foreign gene expression,the VP2 gene of very virulent infectious bursal disease virus(vvIBDV)was inserted into this site,and recombinant LN16-A(rLN16A-vvVP2)was successfully rescued.Single immunization of specificpathogen-free chickens with rLN16A-vvVP2 induced high levels of neutralizing antibodies and provided 100%protection against the virulent aMPV subtype B and vvIBDV.Establishing a reverse genetics system here provides an important foundation for understanding aMPV pathogenesis and developing novel vector vaccines.
基金supported by grants from the National Key R&D Program of China(2022YFD1801000)the Natural Science Foundation of Shanghai,China(24ZR1479200)。
文摘Infectious bursal disease(IBD)is an acute,highly contagious disease that affects chicks(Müller et al.2003).IBD mainly damages the immune organs of chicks,especially the central immune organ,causing immune suppression in diseased chicks(Muller et al.2012).The pathogenic infectious bursal disease virus(IBDV)is a member of the Avira virus genus in the Birnaviridae family.(Harkness et al.1975;Dobos et al.1979;Müller et al.1979).IBDV is prevalent worldwide,causing serious economic losses to the global poultry industry.Currently,vaccination remains the most cost-effective way to prevent IBDV.
基金supported by funding from the National Natural Science Foundation of China(U23A20243 and 32272972 to QZ,32172820 to SX)the Major Science and Technology Project of Gansu Province(22ZD6NA001 to SX)+1 种基金the Youth Innovation Program(Y2023QC30)the Agricultural Science and Technology Innovation Program(CAAS-ASTIP-JBGS-20210102 to SX)of the Chinese Academy of Agricultural Sciences.
文摘Influenza A viruses(IAVs)are single-stranded negative-sense RNA viruses that continually challenge animal and human health.In IAV-infected cells,host RNA-binding proteins play key roles in the life cycle of IAV by directly binding to viral RNA.Here,we examined the role of the host RNA-binding protein nucleophosmin-1(NPM1)in IAV replication.We found that,as a nucleolar phosphoprotein,NPM1 directly binds to viral RNA(vRNA)and inhibits the replication of various subtypes of IAV.NPM1 binding to vRNA competitively reduces the assembly of the viral ribonucleoprotein complex and the viral polymerase activity,thereby reducing the generation of progeny viral RNA and virions.The RNA-binding activity of NPM1,with the key residues T199,T219,T234,and T237,is essential for its anti-influenza function.Taken together,our findings demonstrate that NPM1 acts as an RNA-binding protein and interacts with IAV vRNA to suppress viral replication.
基金supported by grants from the Heilongjiang Provincial Natural Science Foundation of China(LH2022 C109 to DQ L)the National Natural Science Foundation of China(32372985 to YZ L)+1 种基金the National Key Research and Development Program of China(2023YFD1802500 to YZ L)the Tianchi Talent Introduction Plan(IWA2023 to XJ W).
文摘In this study,we developed a highly sensitive enzyme-linked immunosorbent assay(ELISA)using newly produced monoclonal antibodies(mAbs)for detecting horse/donkey IL-1βin cell culture medium and serum samples.The mAbs were generated via the use of a KLH-conjugated peptide and purified equine IL-1βprotein as separate immunogens.Notably,the generated mAbs(3G8 and 5G3)demonstrated no cross-reactivity with other major inflammatory mediators,including IL-1α,IL-1Ra,TNF-α,and SAA.The IL-1βassay,which is based on the screened mAbs,exhibits a detection range of 200-10,000 pg/mL,meeting clinical detection requirements.The coefficients of variation for the repeatability and reproducibility of the assay were both less than 5%,indicating an acceptable level of variation.Subsequently,84 equine and 24 asinine serum samples were collected,and the IL-1βconcentration was measured with both our assay and a commercial kit in parallel.Our results revealed no significant difference between the in-house and commercial ELISA kits for the detection of IL-1βconcentrations in horse sera.Moreover,our ELISA method demonstrated superior sensitivity for IL-1βdetection in donkey samples compared to existing commercial assays.These findings suggest that the newly developed ELISA provides a reliable analytical method for detecting IL-1βin both equine and asinine samples.
基金This research was carried out within the State Assignment of the Ministry of Science and Higher Education of the Russian Federation(project FZGW-2024-0003).
文摘Objective:The objective of this study was to determine the level of methotrexate(MTX)toxicity in the intestines of mice and to evaluate the protective effect of probiotics composed of Streptococcus,Bifidobacterium,and Lactobacillus species on intestinal cells during MTX treatment.Methods:Mice were divided into three groups:control,MTX group(received MTX injections),and MTX+probiotics group(received MTX injections along with a diet containing probiotics).Morphological and histological changes,the level of mitochondrial DNA(mtDNA)damage,the level of lipid peroxidation products,and gene expression in the mice’s small intestine were assessed.Results:We demonstrated that intraperitoneal MTX injections significantly increased mtDNA damage in the liver(p<0.001),small intestine(p<0.001),and blood of mice(p<0.01).MTX elevated the quantity of lipid peroxidation products in the liver and small intestine,indicating its strong prooxidative properties.MTX induced structural changes in the mice’s intestines,characterized by leukocytic infiltration of tissues.Probiotic therapy in mice partially mitigated the morphological and histological changes in the small intestine induced by MTX,reduced oxidative stress,and promoted increased expression of quinone oxidoreductase 1(Nqo1),which participates in both cell protection against oxidative stress and drug/xenobiotic detoxification.Probiotics prevented the upregulation of the proinflammatory cytokine IL-1b in the small intestine and induced increased expression of genes associated with the Nuclear factor erythroid 2-related factor 2/Antioxidant response element(Nrf2/ARE)pathway,an important mechanism of cell protection.Conclusions:Probiotics can be considered an effective approach to reducing the toxicity of MTX during psoriasis or cancer treatment.
