Implantable system maximizes drug concentration and continuously releases drugs near the tumor,which is an effective tool to solve the difficult retention of chemotherapy drugs in bladder cancer.In this work,a novel p...Implantable system maximizes drug concentration and continuously releases drugs near the tumor,which is an effective tool to solve the difficult retention of chemotherapy drugs in bladder cancer.In this work,a novel polysaccharide supramolecular injectable hydrogel(CCA hydrogels for short)is rapidly constructed by simply mixing cationic chitosan,anionic sulfobutyl etherβ-cyclodextrin(SBE-β-CD)and a trace amount of silver ions.The injected hydrogel reconstituted and regained its shape in less than 1 h,and it can still maintain the elasticity suitable for the human body.By packaging the drug directly,the gel achieves a high concentration of doxorubicin,an anticancer drug.Using MB49-luc cells as the model of bladder tumor for anti-tumor in vivo,the CCA-DOX gel has obvious inhibitory effect on bladder tumor,and its inhibitory effect is much greater than that of free DOX.Therefore,this self-healing injectable hydrogel has great potential for in situ treatment of bladder cancer.展开更多
In order to quantitate the bovine immunodeficiency virus (BIV) infection in vitro, a BIV indicator cell line (BIVL) was established by transfecting baby hamster kidney cells with reporter plasmids containing the firef...In order to quantitate the bovine immunodeficiency virus (BIV) infection in vitro, a BIV indicator cell line (BIVL) was established by transfecting baby hamster kidney cells with reporter plasmids containing the firefly luciferase gene driven by a BIV long terminal repeat promoter. The BIV activates promoter activity of the LTR to express luciferase upon infection. BIV infection could therefore by quantified by detection of luciferase activity. Compared to standard assays used to detect BIV infection, the BIVL-based assay is 10 times more sensitive than the the CPE-based assay, and has similar sensitivity with the viral capsid protein Western blot assay. BIV indicator cell line could detect BIV infection specifically. Luciferase activity of BIV infected BIVL cells showed a time dependent manner, and 60 h post infection is the optimal time to detect BIV infection. Luciferase activity of BIVL cells correlates with the BIV capsid protein expression. Moreover, a linear relationship was found between MOI and the activated intensity of luciferase expression. In brief, the BIV indicator cell line is an easy, robust and quantitive method for monitoring BIV infection.展开更多
The ubiquitin-like modifier bISG15 is an antiviral protein found in fetal bovine lung (FBL) cells. Bovine Herpesvirus 1(BHV-1), which is a viral pathogen of cattle, can infect FBL cells and induce cytopathic effects. ...The ubiquitin-like modifier bISG15 is an antiviral protein found in fetal bovine lung (FBL) cells. Bovine Herpesvirus 1(BHV-1), which is a viral pathogen of cattle, can infect FBL cells and induce cytopathic effects. Real-time PCR assays showed that BHV-1's infection could repress the basal or inducible transcription of bISG15 in FBL cells. It demonstrates that this repression effect depends on BHV-1 viral infection and new protein synthesis. Our previous work showed that bIRF-3 was the key factor in the stimulation of bISG15 in FBL cells, so the effect of BHV-1 viral protein on bIRF-3 activating the promoter of bISG15 was confirmed. The luciferase assay showed the BHV-1 viral protein bICP0 inhibited the activation of bISG15 promoter stimulated by bIRF-3. Taken together, our work suggested that BHV-1 had some molecular mechanism to resist the cellular bISG15's antiviral functions.展开更多
BiOBr nanosheets are important photocatalytic nanomaterials. However, their biological effects remain to be explored. In this study, we investigated the antifungal effect of BiOBr nanosheets on Candida albicans. Strik...BiOBr nanosheets are important photocatalytic nanomaterials. However, their biological effects remain to be explored. In this study, we investigated the antifungal effect of BiOBr nanosheets on Candida albicans. Strikingly,the nanosheets strongly inhibited the growth of C. albicans [IC50=(96±4.7) mg/L],hyphal development and biofilm formation. Compareed to the antifungal effect of the cationic surfactant cetyltrimethylammonium bromide, the inhibitory effect of the nanosheets on fungal pathogen was attributed to cetyltrimethylammonium bromide adsorbed by the nanosheets. Thermal gravity analysis and cetyltrimethylammonium bromide release experiment indicated that only 0.42% cetyltrimethylammonium bromide on BiOBr nanosheets was released. Taken together, this study uncovers the contribution of surfactant released from the nanosheets to their antifungal activity.展开更多
On December 7,2022,China adjusted public health control measures,there have been widespread of SARS-CoV-2 infections in Chinese mainland.As the number of infected people increased,the mutation probability of SARS-CoV-...On December 7,2022,China adjusted public health control measures,there have been widespread of SARS-CoV-2 infections in Chinese mainland.As the number of infected people increased,the mutation probability of SARS-CoV-2 is also raised.Therefore,it is of great importance to monitor SARS-CoV-2 variants and its mutations in China.In this current study,665 SARS-CoV-2 genomes from China deposited in the public database were used to analyze the proportion of different variants;to determine the composition of variants in China across different provinces;and analyze specific mutation frequency,focusing on 12 immune escape residues.The results showed that no new mutations were generated on the 12 immune escape residues.The evolutionary analysis of the BF.7 variant circulating in China showed that there is an independent evolutionary branch with unique mutation sites,officially named BF.7.14 by PANGO.This variant may have been imported from Russia to Inner Mongolia at the end of September 2022 and continued its spread in China.The evolutionary analysis of BA.5.2 variant shows that the variant is composed of two sub-variants,named BA.5.2.48 and BA.5.2.49 by PANGO,respectively.This variant may have been imported from abroad to Beijing at the beginning of September 2022 and formed two sub-variants after domestic transmission.Finally,this study showed that current epidemic variants in China were already circulating in other countries,and there were no additional mutations on immune escape residues that could pose a threat to other countries.展开更多
Pseudomonas aeruginosa is a significant pathogen mainly causing healthcare-associated infections(HAIs).Newly emerging high-risk clones of P.aeruginosa with elevated virulence profiles furtherly cause severe community-...Pseudomonas aeruginosa is a significant pathogen mainly causing healthcare-associated infections(HAIs).Newly emerging high-risk clones of P.aeruginosa with elevated virulence profiles furtherly cause severe community-acquired infections(CAIs).Usually,it is not common for P.aeruginosa to co-carry exoU and exoS genes,encoding two type III secretion system(T3SS)effectors.The pathogenicity mechanism of exoS+/exoU+strains of P.aeruginosa remains unclear.Here,we provide detailed evidence for a subset of hypervirulent P.aeruginosa strains,which abundantly co-express and secrete the T3SS effectors ExoS and ExoU.The exoS+/exoU+P.aeruginosa strains were available to cause both HAIs and CAIs.The CAI-associated strains could elicit severe inflammation and hemorrhage,leading to higher death rates in a murine acute pneumonia model,and had great virulence potential in establishing chronic infections,demonstrating hypervirulence when compared to PAO1(exoS+/exoU-)and PA14(exoS-/exoU+).Both ExoS and ExoU were co-expressed and co-secreted in abundance in exoS+/exoU+strains.Their abundant protein secretion could boost exoS+/exoU+strains’potentials for cytotoxicity in vitro and pathogenicity in vivo.Genomic evidence indicates that exoU acquisition is likely mediated by horizontal gene transfer(HGT)of the pathogenicity island PAPI-2,while deletion of exoU was sufficient to mitigate virulence in the exoS+/exoU+strains.Furthermore,bioinformatics analysis showed that such exoS+/exoU+P.aeruginosa strains turned out to be widely distributed across the globe.Overall,the research provide detailed evidence for the high virulence and epidemicity of exoS+/exoU+strains of P.aeruginosa,highlighting an urgent need for surveillance against these high-risk hypervirulent strains.展开更多
Dear Editor, Enteroviruses, including poliovirus, enterovirus 71 (EV71), enterovirus 68, coxsackievirus A16, cause millions of infections every year. The infection can lead to serious human diseases and is a significa...Dear Editor, Enteroviruses, including poliovirus, enterovirus 71 (EV71), enterovirus 68, coxsackievirus A16, cause millions of infections every year. The infection can lead to serious human diseases and is a significant public health problem. Among them, EV71 is an emerging pathogen that causes severe hand, foot and mouth disease (HFMD) and neurological disease, especially in young children. Currently, there is no effective treatment to EV71-caused diseases, partially blaming to a lack of understanding EV71 replication mechanism (Solomon et al., 2010). As a member of Picornaviri-dae, EV71 infection induces a rapid induction of host shutoff, which is marked by the inhibition of cellular protein synthesis (Holland, 1963). In the meantime, viral protein synthesis takes over the cellular translational machinery. It is believed that the cellular protein synthesis shutoff benefits viral replication by relocating cellular resources and facilitating viral escape from host cell immune responses (Cao et al., 2017). Both transcription and translation inhibition have been suggested to contribute to the host protein synthesis shutoff during picornavirus infection (Holland, 1963;Belsham, 2009). However, the relative role of transcription and translation inhibition in virus-induced host shutoff is yet elusive.展开更多
Phenuiviridae,a member of the Bunyavirales order,can lead to significant human morbidity and mortality.Various phenuiviruses target specific cellular proteins and have strategies to counteract the effects of type I in...Phenuiviridae,a member of the Bunyavirales order,can lead to significant human morbidity and mortality.Various phenuiviruses target specific cellular proteins and have strategies to counteract the effects of type I interferon(IFN).Previous studies have shown that phenuiviruses infection inhibits the synthesis of type I IFNs,and viral nonstructural proteins(NSs)had been further identified as an IFN antagonist.This study found that the NSs proteins of Dabie bandavirus(DBV),Sandfly fever Sicilian virus(SFSV),and Uukuniemi virus(UUKV)can inhibit Sendai virus-induced activation of IFN-βpromoter and phosphorylation of IFN regulatory factor 3(IRF3).Moreover,detailed analysis revealed that the phenuivirus NSs protein could directly interact with retinoic acid inducible gene-I(RIG-I)and degrade it via a proteasome-dependent pathway.In short,this study demonstrate a novel mechanism of phenuiviruses to resist host antiviral immunity,which may help understand these pathogens and suggest novel therapeutic approaches.展开更多
Owing to the stimulus-responsive and dynamic properties,magnetism-driven assembly of building blocks to form ordered structures is always a marvelous topic.While abundant magnetic assemblies have been developed in ide...Owing to the stimulus-responsive and dynamic properties,magnetism-driven assembly of building blocks to form ordered structures is always a marvelous topic.While abundant magnetic assemblies have been developed in ideal physical and chemical conditions,it remains a challenge to realize magnetic assembly in complicated biological systems.Herein,we report a kind of biomacromolecule-modified magnetic nanosheets,which are mainly composed of superparamagnetic graphene oxide(Y-Fe2O3@GO),the tumor-targeting protein transferrin(TF),and the mitochondrion-targeting peptide(MitP).Such large-size nanosheets(0.5-1μm),noted as L-Fe2O3@GO-MitP-TF,can successfully in s itu assemble on the surface of tumor cells in a size-dependent and tumor cell-specific way,leading to severe inhibition of nutrient uptake for the tumor cells.More significantly,the nanostructures could efficiently confine the tumor cells,preventing both invasion and metastasis of tumor cells both in vitro and in vivo.Moreover,the 2D assemblies could remarkably disrupt the mitochondria and induce apoptosis,remarkably eradicating tumors under near-infrared(NIR)irradiation.This study sheds light on the development of new nano-systems for efficient cancer therapy and other biomedical applications.展开更多
Macrocycle confinement induced guest near-infrared(NIR)luminescence was research hotspot currently.Here in,we reported a cucurbit[7]uril(CB[7])confined 3,7-bis((E)-2-(pyridin-4-yl)vinyl)-10-Hphenothiazine bridged bis(...Macrocycle confinement induced guest near-infrared(NIR)luminescence was research hotspot currently.Here in,we reported a cucurbit[7]uril(CB[7])confined 3,7-bis((E)-2-(pyridin-4-yl)vinyl)-10-Hphenothiazine bridged bis(4-(4-bromophenyl)pyridine)(G),which not only boosted its NIR luminescence but also realized detection of HClO/ClO^(-)in living cells and lysosome imaging.Fluorescence spectroscopy experiments were performed to calculate the detection ability of probe G to HClO/ClO^(-)up to 147 nmol/L.As compared with G,supramolecular probe G■CB[7]formed after encapsulated by CB[7],the detection ability towards HClO/ClO^(-)was improved to 24 nmol/L which was ascribe to the macrocycle CB[7]confinement increasing the fluorescence intensity to 103 folds.Accompanying the excitation wavelength changing,the fluorescence red-shifted to 820 nm when excited by 570 nm light,which was used to NIR lysosome imaging.Meanwhile,the supramolecular assembly G■CB[7]was also successfully used to highly sense to exogenous HClO/ClO^(-)in RAW 264.7 cells and live animal.展开更多
Bovine foamy virus(BFV) is a complex retrovirus that infects cattle. Like all retroviruses, BFV encodes a transactivator Tas protein(BTas) that increases gene transcription from viral promoters.BFV encodes two promote...Bovine foamy virus(BFV) is a complex retrovirus that infects cattle. Like all retroviruses, BFV encodes a transactivator Tas protein(BTas) that increases gene transcription from viral promoters.BFV encodes two promoters that can interact with BTas, a conserved promoter in the 5' long terminal repeat(LTR) and a unique internal promoter(IP). Our previous study showed that BTas is acetylated by p300 at residues K66, K109, and K110, which markedly enhanced the ability of BTas to bind to DNA. However, whether these residues are important for BFV replication was not determined. Therefore, in this study we provide direct evidence that BTas is required for BFV replication and demonstrate that residues K66, K109, and K110 are critical for BTas function and BFV replication. Full-length infectious clones were generated, which were BTas deficient or contained lysine to arginine(K→R) mutations at position 66, 109, and/or 110. In vivo data indicated that K→R mutations at positions 66, 109, and 110 in BTas impaired transactivation of both the LTR and IP promoters. In addition, the K→R mutations in full-length infectious clones reduced expression of viral proteins, and the triple mutant and BTas deletion completely abrogated viral replication. Taken together, these results indicate that lysine residues at positions 66, 109, and 110 in the BTas protein are crucial for BFV replication and suggest a potential role for BTas acetylation in regulating the viral life cycle.展开更多
In this study,we prepared mitochondrion targeting peptide-grafted magnetic graphene oxide(GO)nanocarriers for efficient impairment of the tumor mitochondria.The two-dimensional GOMNP-MitP nanosheets were synthesized b...In this study,we prepared mitochondrion targeting peptide-grafted magnetic graphene oxide(GO)nanocarriers for efficient impairment of the tumor mitochondria.The two-dimensional GOMNP-MitP nanosheets were synthesized by grafting magnetic y-Fe_(2)O_(3)to the surface of GO,followed by covalent modification of mitochondrion targeting peptide(MitP).GOMNP-MitP exhibited the high capacity of loading the anticancer drug mitoxantrone(MTX),and preferentially targeted the tumor mitochondria.With the aid of alternating magnetic field(AMF),the MTX-loading GOMNP-MitP released MTX to the mitochondria,severely impairing mitochondrial functions,including attenuation of ATP production,decrease in mitochondrial membrane potential(MMP),and further leading to activation of apoptosis.This study realized high-efficient mitochondrion-ta rgeting drug delivery for anticancer therapy by twodimensional nanoplatforms.展开更多
A real-time label-free lateral offset spliced coreless fiber(CF)Mach-Zehnder interferometer(MZI)biosensor functionalized with hydrophobin Grifola frondosa I(HGFI)was proposed for the detection of cytokine tumour necro...A real-time label-free lateral offset spliced coreless fiber(CF)Mach-Zehnder interferometer(MZI)biosensor functionalized with hydrophobin Grifola frondosa I(HGFI)was proposed for the detection of cytokine tumour necrosis factor alpha(TNF-α).The nanolayer self-assembled on the optical fiber surfaces by HGFI rendered the immobilization of probe TNF-αantibody and recognition of antigen TNF-α.Trifluoroacetic acid was utilized to remove the HGFI layer from the glass surface,which was validated by field emission scanning electron microscopy(FESEM)and water contact angle(WCA).Results demonstrated that the processes of HGFI modification,antibody immobilization and specific antibody detection can be monitored in real time.The proposed biosensor exhibited good specificity,repeatability and low detection limit for TNF-α,extending its application in inflammation and disease monitoring.展开更多
Vaccination is critical for population protection from pathogenic infections.However,its efficiency is frequently compromised by a failure of antigen retention and presentation.Herein,we designed a dextran-binding pro...Vaccination is critical for population protection from pathogenic infections.However,its efficiency is frequently compromised by a failure of antigen retention and presentation.Herein,we designed a dextran-binding protein DexBP,which is composed of the carbohydrate-binding domains of Trichoderma reesei cellobiohydrolases Cel6A and Cel7A,together with the sequence of the fluorescent protein mCherry.DexBP was further prepared by engineered Escherichia coli cells and grafted to magnetic nanoparticles.The magnetic nanoparticles were integrated with a dextran/poly(vinyl alcohol)framework and a reactive oxygen species-responsive linker,obtaining magnetic polymeric microgels for carrying pathogen antigen.Similar to amoeba aggregation,the microgels self-assembled to form aggregates and further induced dendritic cell aggregation.This step-by-step assembly retained antigens at lymph nodes,promoted antigen presentation,stimulated humoral immunity,and protected the mice from lifethreatening systemic infections.This study developed a magnetic microgel-assembling platform for dynamically regulating immune response during protection of the body from dangerous infections.展开更多
Intracellular pH critically affects various biological processes,and an appropriate cytoplasmic pH is essential for ensuring bacterial growth.Glucose is the preferred carbon source for most heterotrophs;however,excess...Intracellular pH critically affects various biological processes,and an appropriate cytoplasmic pH is essential for ensuring bacterial growth.Glucose is the preferred carbon source for most heterotrophs;however,excess glucose often causes the accumulation of acidic metabolites,lowering the intracellular pH and inhibiting bacterial growth.Bacillus thuringiensis can effectively cope with glucose-induced stress;unfortunately,little is known about the regulators involved in this process.Here,we document that the target of the dual-function sRNA YhfH,the lipR gene,encodes a LacI-family transcription factor LipR as an intracellular pH regulator when B.thuringiensis BMB171 is suddenly exposed to glucose.Under glucose conditions,lipR deletion leads to early growth arrest by causing a rapid decrease in intracellular pH(~5.4).Then,the direct targets and a binding motif(GAWAWCRWTWTCAT)of LipR were identified based on the electrophoretic mobility shift assay,the DNase-I footprinting assay,and RNA sequencing,and the gapN gene encoding a key enzyme in glycolysis was directly inhibited by LipR.Furthermore,Ni^(2+)is considered a possible effector for LipR.In addition to YhfH,the lipR expression was coregulated by itself,CcpA,and AbrB.Our study reveals that LipR plays a balancing role between glucose metabolism and intracellular pH in B.thuringiensis subjected to glucose stress.展开更多
A novel salt-tolerant heterotrophic nitrification and aerobic denitrification(HN-AD)bacterium was isolated and identified as Halomonas venusta TJPU05(H.venusta TJPU05).The nitrogen removal performance of H.venusta TJP...A novel salt-tolerant heterotrophic nitrification and aerobic denitrification(HN-AD)bacterium was isolated and identified as Halomonas venusta TJPU05(H.venusta TJPU05).The nitrogen removal performance of H.venusta TJPU05 in simulated water(SW)with sole or mixed nitrogen sources and in actual wastewater(AW)with high concentration of salt and nitrogen was investigated.The results showed that 86.12%of NH_(4)^(+)-N,95.68%of NO_(3)^(-)-N,100%of NO_(2)^(-)-N and 84.57%of total nitrogen(TN)could be removed from SW with sole nitrogen sources within 24 h at the utmost.H.venusta TJPU05 could maximally remove 84.06%of NH_(4)^(+)-N,92.33%of NO_(3)^(-)-N,92.9%of NO_(2)^(-)-N and 77.73%of TN from SW with mixed nitrogen source when the salinity was above 8%.The application of H.venusta TJPU05 in treating AW with high salt and high ammonia nitrogen led to removal efficiencies of 50.96%,47.28%and 43.19%for NH_(4)^(+)-N,NO_(3)^(-)-N and TN respectively without any optimization.Furthermore,the activities of nitrogen removal–related enzymes of the strain were also investigated.The successful detection of high level activities of ammonia oxygenase(AMO),hydroxylamine oxidase(HAO),nitrate reductase(NAR)and nitrite reductase(NIR)enzymes under high salinity condition further proved the HN-AD and salt-tolerance capacity of H.venusta TJPU05.These results demonstrated that the H.venusta TJPU05 has great potential in treating high-salinity nitrogenous wastewater.展开更多
Systemic infections caused by life-threatening pathogens represent one of the main factors leading to clinical death.In this study,we developed a pathogen infection-responsive and macrophage endoplasmic reticulum-targ...Systemic infections caused by life-threatening pathogens represent one of the main factors leading to clinical death.In this study,we developed a pathogen infection-responsive and macrophage endoplasmic reticulum-targeting nanoplatform to alleviate systemic infections.The nanoplatform is composed of large-pore mesoporous silica nanoparticles(MSNs)grafted by an endoplasmic reticulum-targeting peptide,and a pathogen infection-responsive cap containing the reactive oxygen speciescleavable boronobenzyl acid linker and bovine serum albumin.The capped MSNs exhibited the capacity to high-efficiently load the antimicrobial peptide melittin,and to rapidly release the cargo triggered by H_(2)O_(2) or the pathogen-macrophage interaction system,but had no obvious toxicity to macrophages.During the interaction with pathogenic Candida albicans cells and macrophages,the melittin-loading nanoplatform MSNE+MEL+TPB strongly inhibited pathogen growth,survived macrophages,and suppressed endoplasmic reticulum stress together with pro-inflammatory cytokine secretion.In a systemic infection model,the nanoplatform efficiently prevented kidney dysfunction,alleviated inflammatory symptoms,and protected the mice from death.This study developed a macrophage organelle-targeting nanoplatform for treatment of life-threatening systemic infections.展开更多
基金National Natural Science Foundation of China(Nos.22131008 and 21971127)the Haihe Laboratory of Sustainable Chemical Transformations for financial support.
文摘Implantable system maximizes drug concentration and continuously releases drugs near the tumor,which is an effective tool to solve the difficult retention of chemotherapy drugs in bladder cancer.In this work,a novel polysaccharide supramolecular injectable hydrogel(CCA hydrogels for short)is rapidly constructed by simply mixing cationic chitosan,anionic sulfobutyl etherβ-cyclodextrin(SBE-β-CD)and a trace amount of silver ions.The injected hydrogel reconstituted and regained its shape in less than 1 h,and it can still maintain the elasticity suitable for the human body.By packaging the drug directly,the gel achieves a high concentration of doxorubicin,an anticancer drug.Using MB49-luc cells as the model of bladder tumor for anti-tumor in vivo,the CCA-DOX gel has obvious inhibitory effect on bladder tumor,and its inhibitory effect is much greater than that of free DOX.Therefore,this self-healing injectable hydrogel has great potential for in situ treatment of bladder cancer.
基金The General Foundation of Tianjin Science Committee for Applied Basic Research (08JCZDJC21000)Chinese Ministry of Education (30770081)
文摘In order to quantitate the bovine immunodeficiency virus (BIV) infection in vitro, a BIV indicator cell line (BIVL) was established by transfecting baby hamster kidney cells with reporter plasmids containing the firefly luciferase gene driven by a BIV long terminal repeat promoter. The BIV activates promoter activity of the LTR to express luciferase upon infection. BIV infection could therefore by quantified by detection of luciferase activity. Compared to standard assays used to detect BIV infection, the BIVL-based assay is 10 times more sensitive than the the CPE-based assay, and has similar sensitivity with the viral capsid protein Western blot assay. BIV indicator cell line could detect BIV infection specifically. Luciferase activity of BIV infected BIVL cells showed a time dependent manner, and 60 h post infection is the optimal time to detect BIV infection. Luciferase activity of BIVL cells correlates with the BIV capsid protein expression. Moreover, a linear relationship was found between MOI and the activated intensity of luciferase expression. In brief, the BIV indicator cell line is an easy, robust and quantitive method for monitoring BIV infection.
基金National Natural Science Foundation of China (81071343) and (30970162)
文摘The ubiquitin-like modifier bISG15 is an antiviral protein found in fetal bovine lung (FBL) cells. Bovine Herpesvirus 1(BHV-1), which is a viral pathogen of cattle, can infect FBL cells and induce cytopathic effects. Real-time PCR assays showed that BHV-1's infection could repress the basal or inducible transcription of bISG15 in FBL cells. It demonstrates that this repression effect depends on BHV-1 viral infection and new protein synthesis. Our previous work showed that bIRF-3 was the key factor in the stimulation of bISG15 in FBL cells, so the effect of BHV-1 viral protein on bIRF-3 activating the promoter of bISG15 was confirmed. The luciferase assay showed the BHV-1 viral protein bICP0 inhibited the activation of bISG15 promoter stimulated by bIRF-3. Taken together, our work suggested that BHV-1 had some molecular mechanism to resist the cellular bISG15's antiviral functions.
基金supported by Tianjin 131 Innovative Talent Training ProjectPostdoctoral Science Foundation
文摘BiOBr nanosheets are important photocatalytic nanomaterials. However, their biological effects remain to be explored. In this study, we investigated the antifungal effect of BiOBr nanosheets on Candida albicans. Strikingly,the nanosheets strongly inhibited the growth of C. albicans [IC50=(96±4.7) mg/L],hyphal development and biofilm formation. Compareed to the antifungal effect of the cationic surfactant cetyltrimethylammonium bromide, the inhibitory effect of the nanosheets on fungal pathogen was attributed to cetyltrimethylammonium bromide adsorbed by the nanosheets. Thermal gravity analysis and cetyltrimethylammonium bromide release experiment indicated that only 0.42% cetyltrimethylammonium bromide on BiOBr nanosheets was released. Taken together, this study uncovers the contribution of surfactant released from the nanosheets to their antifungal activity.
基金This work was supported by grants from consultancy project(2022-JB-06)by the Chinese Academy of Engineering(CAE).
文摘On December 7,2022,China adjusted public health control measures,there have been widespread of SARS-CoV-2 infections in Chinese mainland.As the number of infected people increased,the mutation probability of SARS-CoV-2 is also raised.Therefore,it is of great importance to monitor SARS-CoV-2 variants and its mutations in China.In this current study,665 SARS-CoV-2 genomes from China deposited in the public database were used to analyze the proportion of different variants;to determine the composition of variants in China across different provinces;and analyze specific mutation frequency,focusing on 12 immune escape residues.The results showed that no new mutations were generated on the 12 immune escape residues.The evolutionary analysis of the BF.7 variant circulating in China showed that there is an independent evolutionary branch with unique mutation sites,officially named BF.7.14 by PANGO.This variant may have been imported from Russia to Inner Mongolia at the end of September 2022 and continued its spread in China.The evolutionary analysis of BA.5.2 variant shows that the variant is composed of two sub-variants,named BA.5.2.48 and BA.5.2.49 by PANGO,respectively.This variant may have been imported from abroad to Beijing at the beginning of September 2022 and formed two sub-variants after domestic transmission.Finally,this study showed that current epidemic variants in China were already circulating in other countries,and there were no additional mutations on immune escape residues that could pose a threat to other countries.
基金supported by grants from the National Key R&D Program of China(2021YFC2302005)the Joint Funds of the International Development Research Center of Canada(109282-001)the National Key R&D Program of China(2021YFC2301004 and 2017YFE0125600).
文摘Pseudomonas aeruginosa is a significant pathogen mainly causing healthcare-associated infections(HAIs).Newly emerging high-risk clones of P.aeruginosa with elevated virulence profiles furtherly cause severe community-acquired infections(CAIs).Usually,it is not common for P.aeruginosa to co-carry exoU and exoS genes,encoding two type III secretion system(T3SS)effectors.The pathogenicity mechanism of exoS+/exoU+strains of P.aeruginosa remains unclear.Here,we provide detailed evidence for a subset of hypervirulent P.aeruginosa strains,which abundantly co-express and secrete the T3SS effectors ExoS and ExoU.The exoS+/exoU+P.aeruginosa strains were available to cause both HAIs and CAIs.The CAI-associated strains could elicit severe inflammation and hemorrhage,leading to higher death rates in a murine acute pneumonia model,and had great virulence potential in establishing chronic infections,demonstrating hypervirulence when compared to PAO1(exoS+/exoU-)and PA14(exoS-/exoU+).Both ExoS and ExoU were co-expressed and co-secreted in abundance in exoS+/exoU+strains.Their abundant protein secretion could boost exoS+/exoU+strains’potentials for cytotoxicity in vitro and pathogenicity in vivo.Genomic evidence indicates that exoU acquisition is likely mediated by horizontal gene transfer(HGT)of the pathogenicity island PAPI-2,while deletion of exoU was sufficient to mitigate virulence in the exoS+/exoU+strains.Furthermore,bioinformatics analysis showed that such exoS+/exoU+P.aeruginosa strains turned out to be widely distributed across the globe.Overall,the research provide detailed evidence for the high virulence and epidemicity of exoS+/exoU+strains of P.aeruginosa,highlighting an urgent need for surveillance against these high-risk hypervirulent strains.
文摘Dear Editor, Enteroviruses, including poliovirus, enterovirus 71 (EV71), enterovirus 68, coxsackievirus A16, cause millions of infections every year. The infection can lead to serious human diseases and is a significant public health problem. Among them, EV71 is an emerging pathogen that causes severe hand, foot and mouth disease (HFMD) and neurological disease, especially in young children. Currently, there is no effective treatment to EV71-caused diseases, partially blaming to a lack of understanding EV71 replication mechanism (Solomon et al., 2010). As a member of Picornaviri-dae, EV71 infection induces a rapid induction of host shutoff, which is marked by the inhibition of cellular protein synthesis (Holland, 1963). In the meantime, viral protein synthesis takes over the cellular translational machinery. It is believed that the cellular protein synthesis shutoff benefits viral replication by relocating cellular resources and facilitating viral escape from host cell immune responses (Cao et al., 2017). Both transcription and translation inhibition have been suggested to contribute to the host protein synthesis shutoff during picornavirus infection (Holland, 1963;Belsham, 2009). However, the relative role of transcription and translation inhibition in virus-induced host shutoff is yet elusive.
基金We thank Liu Yang for assistance in the confocal microscopy studies.We also thank Lishu Zheng for providing Sendai virus.This work was supported by the National Science Foundation of China(grant numbers 31270201)the National Basic Research Program(973 Program)of China(grant numbers 2011CB504700).
文摘Phenuiviridae,a member of the Bunyavirales order,can lead to significant human morbidity and mortality.Various phenuiviruses target specific cellular proteins and have strategies to counteract the effects of type I interferon(IFN).Previous studies have shown that phenuiviruses infection inhibits the synthesis of type I IFNs,and viral nonstructural proteins(NSs)had been further identified as an IFN antagonist.This study found that the NSs proteins of Dabie bandavirus(DBV),Sandfly fever Sicilian virus(SFSV),and Uukuniemi virus(UUKV)can inhibit Sendai virus-induced activation of IFN-βpromoter and phosphorylation of IFN regulatory factor 3(IRF3).Moreover,detailed analysis revealed that the phenuivirus NSs protein could directly interact with retinoic acid inducible gene-I(RIG-I)and degrade it via a proteasome-dependent pathway.In short,this study demonstrate a novel mechanism of phenuiviruses to resist host antiviral immunity,which may help understand these pathogens and suggest novel therapeutic approaches.
基金This work was financially funded by the National Natural Science Foundation of China(Nos.31870139,21761132008).
文摘Owing to the stimulus-responsive and dynamic properties,magnetism-driven assembly of building blocks to form ordered structures is always a marvelous topic.While abundant magnetic assemblies have been developed in ideal physical and chemical conditions,it remains a challenge to realize magnetic assembly in complicated biological systems.Herein,we report a kind of biomacromolecule-modified magnetic nanosheets,which are mainly composed of superparamagnetic graphene oxide(Y-Fe2O3@GO),the tumor-targeting protein transferrin(TF),and the mitochondrion-targeting peptide(MitP).Such large-size nanosheets(0.5-1μm),noted as L-Fe2O3@GO-MitP-TF,can successfully in s itu assemble on the surface of tumor cells in a size-dependent and tumor cell-specific way,leading to severe inhibition of nutrient uptake for the tumor cells.More significantly,the nanostructures could efficiently confine the tumor cells,preventing both invasion and metastasis of tumor cells both in vitro and in vivo.Moreover,the 2D assemblies could remarkably disrupt the mitochondria and induce apoptosis,remarkably eradicating tumors under near-infrared(NIR)irradiation.This study sheds light on the development of new nano-systems for efficient cancer therapy and other biomedical applications.
基金financially supported by the National Natural Science Foundation of China(No.22131008)Liaocheng University Start-up Fund for Doctoral Scientific Research(No.318052327)。
文摘Macrocycle confinement induced guest near-infrared(NIR)luminescence was research hotspot currently.Here in,we reported a cucurbit[7]uril(CB[7])confined 3,7-bis((E)-2-(pyridin-4-yl)vinyl)-10-Hphenothiazine bridged bis(4-(4-bromophenyl)pyridine)(G),which not only boosted its NIR luminescence but also realized detection of HClO/ClO^(-)in living cells and lysosome imaging.Fluorescence spectroscopy experiments were performed to calculate the detection ability of probe G to HClO/ClO^(-)up to 147 nmol/L.As compared with G,supramolecular probe G■CB[7]formed after encapsulated by CB[7],the detection ability towards HClO/ClO^(-)was improved to 24 nmol/L which was ascribe to the macrocycle CB[7]confinement increasing the fluorescence intensity to 103 folds.Accompanying the excitation wavelength changing,the fluorescence red-shifted to 820 nm when excited by 570 nm light,which was used to NIR lysosome imaging.Meanwhile,the supramolecular assembly G■CB[7]was also successfully used to highly sense to exogenous HClO/ClO^(-)in RAW 264.7 cells and live animal.
基金supported by grants from the National Natural Science Foundation of China(Na.31370182)Tianjin Research Program and Application Foundation and Advanced Technology(Na.12YFQNJC02300)111 Project(B08011)
文摘Bovine foamy virus(BFV) is a complex retrovirus that infects cattle. Like all retroviruses, BFV encodes a transactivator Tas protein(BTas) that increases gene transcription from viral promoters.BFV encodes two promoters that can interact with BTas, a conserved promoter in the 5' long terminal repeat(LTR) and a unique internal promoter(IP). Our previous study showed that BTas is acetylated by p300 at residues K66, K109, and K110, which markedly enhanced the ability of BTas to bind to DNA. However, whether these residues are important for BFV replication was not determined. Therefore, in this study we provide direct evidence that BTas is required for BFV replication and demonstrate that residues K66, K109, and K110 are critical for BTas function and BFV replication. Full-length infectious clones were generated, which were BTas deficient or contained lysine to arginine(K→R) mutations at position 66, 109, and/or 110. In vivo data indicated that K→R mutations at positions 66, 109, and 110 in BTas impaired transactivation of both the LTR and IP promoters. In addition, the K→R mutations in full-length infectious clones reduced expression of viral proteins, and the triple mutant and BTas deletion completely abrogated viral replication. Taken together, these results indicate that lysine residues at positions 66, 109, and 110 in the BTas protein are crucial for BFV replication and suggest a potential role for BTas acetylation in regulating the viral life cycle.
基金supported by National Natural Science Foundation of China(No.31870139)Natural Science Foundation of Tianjin(No.19JCZDJC33800)+1 种基金Tianjin Synthetic Biotechnology Innovation Capacity Improvement Project(No.TSBICIP-KJGG-006)the Fundamental Research for the Central Universities。
文摘In this study,we prepared mitochondrion targeting peptide-grafted magnetic graphene oxide(GO)nanocarriers for efficient impairment of the tumor mitochondria.The two-dimensional GOMNP-MitP nanosheets were synthesized by grafting magnetic y-Fe_(2)O_(3)to the surface of GO,followed by covalent modification of mitochondrion targeting peptide(MitP).GOMNP-MitP exhibited the high capacity of loading the anticancer drug mitoxantrone(MTX),and preferentially targeted the tumor mitochondria.With the aid of alternating magnetic field(AMF),the MTX-loading GOMNP-MitP released MTX to the mitochondria,severely impairing mitochondrial functions,including attenuation of ATP production,decrease in mitochondrial membrane potential(MMP),and further leading to activation of apoptosis.This study realized high-efficient mitochondrion-ta rgeting drug delivery for anticancer therapy by twodimensional nanoplatforms.
基金supported by the Sino-Swiss Scientific and Technological Cooperation Project supported by the Ministry of Science and Technology of China(No.2015DFG32140)the National Key Research and Development Program of China(Nos.2018YFA0900100 and 2018YFB1802302)+2 种基金the National Natural Science Foundation of China(Nos.11774181,11804250,11904180,11904262,61875091 and 62105164)the Natural Science Foundation of Tianjin City(Nos.19JCYBJC16700,20JCQNJC01480,21JCQNJC00210 and 21JCYBJC00080)the Tianjin Education Commission Scientific Research Project(Nos.2018KJ146 and 2019KJ016).
文摘A real-time label-free lateral offset spliced coreless fiber(CF)Mach-Zehnder interferometer(MZI)biosensor functionalized with hydrophobin Grifola frondosa I(HGFI)was proposed for the detection of cytokine tumour necrosis factor alpha(TNF-α).The nanolayer self-assembled on the optical fiber surfaces by HGFI rendered the immobilization of probe TNF-αantibody and recognition of antigen TNF-α.Trifluoroacetic acid was utilized to remove the HGFI layer from the glass surface,which was validated by field emission scanning electron microscopy(FESEM)and water contact angle(WCA).Results demonstrated that the processes of HGFI modification,antibody immobilization and specific antibody detection can be monitored in real time.The proposed biosensor exhibited good specificity,repeatability and low detection limit for TNF-α,extending its application in inflammation and disease monitoring.
基金This work was supported by the National Natural Science Foundation of China(Nos.3217010793 and 31870139)Tianjin Synthetic Biotechnology Innovation Capacity Improvement Project(No.TSBICIP-KJGG-006)+1 种基金the Natural Science Foundation of Tianjin(No.19JCZDJC33800)the Fundamental Research Funds for the Central Universities.
文摘Vaccination is critical for population protection from pathogenic infections.However,its efficiency is frequently compromised by a failure of antigen retention and presentation.Herein,we designed a dextran-binding protein DexBP,which is composed of the carbohydrate-binding domains of Trichoderma reesei cellobiohydrolases Cel6A and Cel7A,together with the sequence of the fluorescent protein mCherry.DexBP was further prepared by engineered Escherichia coli cells and grafted to magnetic nanoparticles.The magnetic nanoparticles were integrated with a dextran/poly(vinyl alcohol)framework and a reactive oxygen species-responsive linker,obtaining magnetic polymeric microgels for carrying pathogen antigen.Similar to amoeba aggregation,the microgels self-assembled to form aggregates and further induced dendritic cell aggregation.This step-by-step assembly retained antigens at lymph nodes,promoted antigen presentation,stimulated humoral immunity,and protected the mice from lifethreatening systemic infections.This study developed a magnetic microgel-assembling platform for dynamically regulating immune response during protection of the body from dangerous infections.
基金supported by the National Key Research and Development Program of China(2018YFA0900100)the National Natural Science Foundation of China(31670081).
文摘Intracellular pH critically affects various biological processes,and an appropriate cytoplasmic pH is essential for ensuring bacterial growth.Glucose is the preferred carbon source for most heterotrophs;however,excess glucose often causes the accumulation of acidic metabolites,lowering the intracellular pH and inhibiting bacterial growth.Bacillus thuringiensis can effectively cope with glucose-induced stress;unfortunately,little is known about the regulators involved in this process.Here,we document that the target of the dual-function sRNA YhfH,the lipR gene,encodes a LacI-family transcription factor LipR as an intracellular pH regulator when B.thuringiensis BMB171 is suddenly exposed to glucose.Under glucose conditions,lipR deletion leads to early growth arrest by causing a rapid decrease in intracellular pH(~5.4).Then,the direct targets and a binding motif(GAWAWCRWTWTCAT)of LipR were identified based on the electrophoretic mobility shift assay,the DNase-I footprinting assay,and RNA sequencing,and the gapN gene encoding a key enzyme in glycolysis was directly inhibited by LipR.Furthermore,Ni^(2+)is considered a possible effector for LipR.In addition to YhfH,the lipR expression was coregulated by itself,CcpA,and AbrB.Our study reveals that LipR plays a balancing role between glucose metabolism and intracellular pH in B.thuringiensis subjected to glucose stress.
基金the National Natural Science Foundation of China(31870139 and 81873961)the Natural Science Foundation of Tianjin(19JCZDJC33800)+1 种基金the National Training Program of Innovation and Entrepreneurship for Undergraduates(201810055105)the Fundamental Research for the Central Universities。
基金supported by the National Natural Science Foundation of China(Grant No.22075207)the Training Program of Innovation and Entrepreneurship for Undergraduates(No.201910058052).
文摘A novel salt-tolerant heterotrophic nitrification and aerobic denitrification(HN-AD)bacterium was isolated and identified as Halomonas venusta TJPU05(H.venusta TJPU05).The nitrogen removal performance of H.venusta TJPU05 in simulated water(SW)with sole or mixed nitrogen sources and in actual wastewater(AW)with high concentration of salt and nitrogen was investigated.The results showed that 86.12%of NH_(4)^(+)-N,95.68%of NO_(3)^(-)-N,100%of NO_(2)^(-)-N and 84.57%of total nitrogen(TN)could be removed from SW with sole nitrogen sources within 24 h at the utmost.H.venusta TJPU05 could maximally remove 84.06%of NH_(4)^(+)-N,92.33%of NO_(3)^(-)-N,92.9%of NO_(2)^(-)-N and 77.73%of TN from SW with mixed nitrogen source when the salinity was above 8%.The application of H.venusta TJPU05 in treating AW with high salt and high ammonia nitrogen led to removal efficiencies of 50.96%,47.28%and 43.19%for NH_(4)^(+)-N,NO_(3)^(-)-N and TN respectively without any optimization.Furthermore,the activities of nitrogen removal–related enzymes of the strain were also investigated.The successful detection of high level activities of ammonia oxygenase(AMO),hydroxylamine oxidase(HAO),nitrate reductase(NAR)and nitrite reductase(NIR)enzymes under high salinity condition further proved the HN-AD and salt-tolerance capacity of H.venusta TJPU05.These results demonstrated that the H.venusta TJPU05 has great potential in treating high-salinity nitrogenous wastewater.
基金supported by the National Natural Science Foundation of China(21705117,22174110,21904095 and 22004089)the Elite Scholar Program of Tianjin University(2019XRG-0065)+2 种基金the Program of Tianjin Science and Technology Major Project and Engineering(19ZXYXSY00090)the Program for Chang Jiang Scholars and Innovative Research Team,Ministry of Education,China(IRT-16R61)the Special Fund Project for the Central Government to Guide Local Science and Technology Development(2020)。
基金supported by the National Natural Science Foundation of China(Nos.3217010793 and 31870139)Natural Science Foundation of Tianjin(No.19JCZDJC33800)Tianjin Synthetic Biotechnology Innovation Capacity Improvement Project(No.TSBICIP-KJGG-006).
文摘Systemic infections caused by life-threatening pathogens represent one of the main factors leading to clinical death.In this study,we developed a pathogen infection-responsive and macrophage endoplasmic reticulum-targeting nanoplatform to alleviate systemic infections.The nanoplatform is composed of large-pore mesoporous silica nanoparticles(MSNs)grafted by an endoplasmic reticulum-targeting peptide,and a pathogen infection-responsive cap containing the reactive oxygen speciescleavable boronobenzyl acid linker and bovine serum albumin.The capped MSNs exhibited the capacity to high-efficiently load the antimicrobial peptide melittin,and to rapidly release the cargo triggered by H_(2)O_(2) or the pathogen-macrophage interaction system,but had no obvious toxicity to macrophages.During the interaction with pathogenic Candida albicans cells and macrophages,the melittin-loading nanoplatform MSNE+MEL+TPB strongly inhibited pathogen growth,survived macrophages,and suppressed endoplasmic reticulum stress together with pro-inflammatory cytokine secretion.In a systemic infection model,the nanoplatform efficiently prevented kidney dysfunction,alleviated inflammatory symptoms,and protected the mice from death.This study developed a macrophage organelle-targeting nanoplatform for treatment of life-threatening systemic infections.