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1.
PLoS Biol ; 21(3): e3002039, 2023 03.
Article in English | MEDLINE | ID: mdl-36930652

ABSTRACT

Coronaviruses (CoVs) comprise a group of important human and animal pathogens. Despite extensive research in the past 3 years, the host innate immune defense mechanisms against CoVs remain incompletely understood, limiting the development of effective antivirals and non-antibody-based therapeutics. Here, we performed an integrated transcriptomic analysis of porcine jejunal epithelial cells infected with porcine epidemic diarrhea virus (PEDV) and identified cytidine/uridine monophosphate kinase 2 (CMPK2) as a potential host restriction factor. CMPK2 exhibited modest antiviral activity against PEDV infection in multiple cell types. CMPK2 transcription was regulated by interferon-dependent and interferon regulatory factor 1 (IRF1)-dependent pathways post-PEDV infection. We demonstrated that 3'-deoxy-3',4'-didehydro-cytidine triphosphate (ddhCTP) catalysis by Viperin, another interferon-stimulated protein, was essential for CMPK2's antiviral activity. Both the classical catalytic domain and the newly identified antiviral key domain of CMPK2 played crucial roles in this process. Together, CMPK2, viperin, and ddhCTP suppressed the replication of several other CoVs of different genera through inhibition of the RNA-dependent RNA polymerase activities. Our results revealed a previously unknown function of CMPK2 as a restriction factor for CoVs, implying that CMPK2 might be an alternative target of interfering with the viral polymerase activity.


Subject(s)
Coronavirus Infections , Coronavirus , Porcine epidemic diarrhea virus , Humans , Animals , Swine , Interferons , Antiviral Agents/pharmacology , Proteins/genetics , Porcine epidemic diarrhea virus/genetics
2.
J Virol ; 98(4): e0006424, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38488360

ABSTRACT

As one of the most important causative agents of severe gastroenteritis in children, piglets, and other young animals, species A rotaviruses have adversely impacted both human health and the global swine industry. Vaccines against rotaviruses (RVs) are insufficiently effective, and no specific treatment is available. To understand the relationships between porcine RV (PoRV) infection and enterocytes in terms of the cellular lipid metabolism, we performed an untargeted liquid chromatography mass spectrometry (LC-MS) lipidomics analysis of PoRV-infected IPEC-J2 cells. Herein, a total of 451 lipids (263 upregulated lipids and 188 downregulated lipids), spanning sphingolipid, glycerolipid, and glycerophospholipids, were significantly altered compared with the mock-infected group. Interestingly, almost all the ceramides among these lipids were upregulated during PoRV infection. LC-MS analysis was used to validated the lipidomics data and demonstrated that PoRV replication increased the levels of long-chain ceramides (C16-ceramide, C18-ceramide, and C24-ceramide) in cells. Furthermore, we found that these long-chain ceramides markedly inhibited PoRV infection and that their antiviral actions were exerted in the replication stage of PoRV infection. Moreover, downregulation of endogenous ceramides with the ceramide metabolic inhibitors enhanced PoRV propagation. Increasing the levels of ceramides by the addition of C6-ceramide strikingly suppressed the replication of diverse RV strains. We further found that the treatment with an apoptotic inhibitor could reverse the antiviral activity of ceramide against PoRV replication, demonstrating that ceramide restricted RV infection by inducing apoptosis. Altogether, this study revealed that ceramides played an antiviral role against RV infection, providing potential approaches for the development of antiviral therapies.IMPORTANCERotaviruses (RVs) are among the most important zoonosis viruses, which mainly infected enterocytes of the intestinal epithelium causing diarrhea in children and the young of many mammalian and avian species. Lipids play an essential role in viral infection. A comprehensive understanding of the interaction between RV and lipid metabolism in the enterocytes will be helpful to control RV infection. Here, we mapped changes in enterocyte lipids following porcine RV (PoRV) infection using an untargeted lipidomics approach. We found that PoRV infection altered the metabolism of various lipid species, especially ceramides (derivatives of the sphingosine). We further demonstrated that PoRV infection increased the accumulation of ceramides and that ceramides exerted antiviral effects on RV replication by inducing apoptosis. Our findings fill a gap in understanding the alterations of lipid metabolism in RV-infected enterocytes and highlight the antiviral effects of ceramides on RV infection, suggesting potential approaches to control RV infection.


Subject(s)
Ceramides , Rotavirus Infections , Rotavirus , Animals , Ceramides/metabolism , Lipid Metabolism , Lipidomics , Rotavirus/physiology , Swine , Enterocytes/metabolism , Enterocytes/virology , Rotavirus Infections/metabolism , Cell Line
3.
J Virol ; 98(5): e0021224, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38591886

ABSTRACT

Porcine rotaviruses (PoRVs) cause severe economic losses in the swine industry. P[7] and P[23] are the predominant genotypes circulating on farms, but no vaccine is yet available. Here, we developed a bivalent subunit PoRV vaccine using truncated versions (VP4*) of the VP4 proteins from P[7] and P[23]. The vaccination of mice with the bivalent subunit vaccine elicited more robust neutralizing antibodies (NAbs) and cellular immune responses than its components, even at high doses. The bivalent subunit vaccine and inactivated bivalent vaccine prepared from strains PoRVs G9P[7] and G9P[23] were used to examine their protective efficacy in sows and suckling piglets after passive immunization. The immunized sows showed significantly elevated NAbs in the serum and colostrum, and the suckling piglets acquired high levels of sIgA antibodies from the colostrum. Challenging subunit-vaccinated or inactivated-vaccinated piglets with homologous virulent strains did not induce diarrhea, except in one or two piglets, which had mild diarrhea. Immunization with the bivalent subunit vaccine and inactivated vaccine also alleviated the microscopic lesions in the intestinal tissues caused by the challenge with the corresponding homologous virulent strain. However, all the piglets in the challenged group displayed mild to watery diarrhea and high levels of viral shedding, whereas the feces and intestines of the piglets in the bivalent subunit vaccine and inactivated vaccine groups had lower viral loads. In summary, our data show for the first time that a bivalent subunit vaccine combining VP4*P[7] and VP4*P[23] effectively protects piglets against the diarrhea caused by homologous virulent strains.IMPORTANCEPoRVs are the main causes of diarrhea in piglets worldwide. The multisegmented genome of PoRVs allows the reassortment of VP4 and VP7 genes from different RV species and strains. The P[7] and P[23] are the predominant genotypes circulating in pig farms, but no vaccine is available at present in China. Subunit vaccines, as nonreplicating vaccines, are an option to cope with variable genotypes. Here, we have developed a bivalent subunit candidate vaccine based on a truncated VP4 protein, which induced robust humoral and cellular immune responses and protected piglets against challenge with homologous PoRV. It also appears to be safe. These data show that the truncated VP4-protein-based subunit vaccine is a promising candidate for the prevention of PoRV diarrhea.


Subject(s)
Rotavirus Vaccines , Vaccines, Subunit , Animals , Female , Mice , Antibodies, Neutralizing/blood , Antibodies, Neutralizing/immunology , Antibodies, Viral/blood , Antibodies, Viral/immunology , Capsid Proteins/immunology , Capsid Proteins/genetics , Diarrhea/prevention & control , Diarrhea/virology , Diarrhea/veterinary , Diarrhea/immunology , Genotype , Immunity, Cellular , Mice, Inbred BALB C , Rotavirus/immunology , Rotavirus Infections/prevention & control , Rotavirus Infections/veterinary , Rotavirus Infections/immunology , Rotavirus Infections/virology , Rotavirus Vaccines/immunology , Rotavirus Vaccines/administration & dosage , Swine , Swine Diseases/prevention & control , Swine Diseases/virology , Swine Diseases/immunology , Vaccination , Vaccines, Subunit/immunology , Vaccines, Subunit/administration & dosage , Vaccines, Synthetic/immunology , Vaccines, Synthetic/administration & dosage
4.
J Immunol ; 210(3): 271-282, 2023 02 01.
Article in English | MEDLINE | ID: mdl-36548460

ABSTRACT

Swine coronavirus-porcine epidemic diarrhea virus (PEDV) with specific susceptibility to pigs has existed for decades, and recurrent epidemics caused by mutant strains have swept the world again since 2010. In this study, single-cell RNA sequencing was used to perform for the first time, to our knowledge, a systematic analysis of pig jejunum infected with PEDV. Pig intestinal cell types were identified by representative markers and identified a new tuft cell marker, DNAH11. Excepting enterocyte cells, the goblet and tuft cells confirmed susceptibility to PEDV. Enrichment analyses showed that PEDV infection resulted in upregulation of cell apoptosis, junctions, and the MAPK signaling pathway and downregulation of oxidative phosphorylation in intestinal epithelial cell types. The T cell differentiation and IgA production were decreased in T and B cells, respectively. Cytokine gene analyses revealed that PEDV infection downregulated CXCL8, CXCL16, and IL34 in tuft cells and upregulated IL22 in Th17 cells. Further studies found that infection of goblet cells with PEDV decreased the expression of MUC2, as well as other mucin components. Moreover, the antimicrobial peptide REG3G was obviously upregulated through the IL33-STAT3 signaling pathway in enterocyte cells in the PEDV-infected group, and REG3G inhibited the PEDV replication. Finally, enterocyte cells expressed almost all coronavirus entry factors, and PEDV infection caused significant upregulation of the coronavirus receptor ACE2 in enterocyte cells. In summary, this study systematically investigated the responses of different cell types in the jejunum of piglets after PEDV infection, which deepened the understanding of viral pathogenesis.


Subject(s)
Coronavirus Infections , Porcine epidemic diarrhea virus , Swine , Animals , Porcine epidemic diarrhea virus/genetics , Transcriptome , Intestine, Small/pathology , Intestines/pathology , Sequence Analysis, RNA
5.
J Virol ; 97(11): e0095823, 2023 Nov 30.
Article in English | MEDLINE | ID: mdl-37846983

ABSTRACT

IMPORTANCE: As an emerging porcine enteropathogenic coronavirus that has the potential to infect humans, porcine deltacoronavirus (PDCoV) is receiving increasing attention. However, no effective commercially available vaccines against this virus are available. In this work, we designed a spike (S) protein and receptor-binding domain (RBD) trimer as a candidate PDCoV subunit vaccine. We demonstrated that S protein induced more robust humoral and cellular immune responses than the RBD trimer in mice. Furthermore, the protective efficacy of the S protein was compared with that of inactivated PDCoV vaccines in piglets and sows. Of note, the immunized piglets and suckling pig showed a high level of NAbs and were associated with reduced virus shedding and mild diarrhea, and the high level of NAbs was maintained for at least 4 months. Importantly, we demonstrated that S protein-based subunit vaccines conferred significant protection against PDCoV infection.


Subject(s)
Coronavirus Infections , Coronavirus , Swine Diseases , Vaccines, Subunit , Animals , Female , Humans , Mice , Coronavirus/genetics , Coronavirus Infections/prevention & control , Coronavirus Infections/veterinary , Deltacoronavirus , Swine , Vaccines, Subunit/administration & dosage
6.
Microb Pathog ; 190: 106612, 2024 May.
Article in English | MEDLINE | ID: mdl-38467166

ABSTRACT

Rotavirus group A (RVA) is a main pathogen causing diarrheal diseases in humans and animals. Various genotypes are prevalent in the Chinese pig herd. The genetic diversity of RVA lead to distinctly characteristics. In the present study, a porcine RVA strain, named AHFY2022, was successfully isolated from the small intestine tissue of piglets with severe diarrhea. The AHFY2022 strain was identified by cytopathic effects (CPE) observation, indirect immunofluorescence assay (IFA), electron microscopy (EM), high-throughput sequencing, and pathogenesis to piglets. The genomic investigation using NGS data revealed that AHFY2022 exhibited the genotypes G9-P[23]-I5-R1-C1-M1-A8-N1-T1-E1-H1, using the online platform the Bacterial and Viral Bioinformatics Resource Center (BV-BRC) (https://www.bv-brc.org/). Moreover, experimental inoculation in 5-day-old and 27-day-old piglets demonstrated that AHFY2022 caused severe diarrhea, fecal shedding, small intestinal villi damage, and colonization in all challenged piglets. Taken together, our results detailed the virological features of the porcine rotavirus G9P[23] from China, including the whole-genome sequences, genotypes, growth kinetics in MA104 cells and the pathogenicity in suckling piglets.


Subject(s)
Diarrhea , Genome, Viral , Genotype , Phylogeny , Rotavirus Infections , Rotavirus , Swine Diseases , Animals , Rotavirus/genetics , Rotavirus/isolation & purification , Rotavirus/classification , Rotavirus/pathogenicity , Swine , Rotavirus Infections/virology , Rotavirus Infections/veterinary , China , Swine Diseases/virology , Diarrhea/virology , Diarrhea/veterinary , Intestine, Small/virology , Intestine, Small/pathology , Feces/virology , High-Throughput Nucleotide Sequencing
7.
Development ; 147(18)2020 09 28.
Article in English | MEDLINE | ID: mdl-32988975

ABSTRACT

Teleost zebrafish and neonatal mammalian hearts exhibit the remarkable capacity to regenerate through dedifferentiation and proliferation of pre-existing cardiomyocytes (CMs). Although many mitogenic signals that stimulate zebrafish heart regeneration have been identified, transcriptional programs that restrain injury-induced CM renewal are incompletely understood. Here, we report that mutations in gridlock (grl; also known as hey2), encoding a Hairy-related basic helix-loop-helix transcriptional repressor, enhance CM proliferation and reduce fibrosis following damage. In contrast, myocardial grl induction blunts CM dedifferentiation and regenerative responses to heart injury. RNA sequencing analyses uncover Smyd2 lysine methyltransferase (KMT) as a key transcriptional target repressed by Grl. Reduction in Grl protein levels triggered by injury induces smyd2 expression at the wound myocardium, enhancing CM proliferation. We show that Smyd2 functions as a methyltransferase and modulates the Stat3 methylation and phosphorylation activity. Inhibition of the KMT activity of Smyd2 reduces phosphorylated Stat3 at cardiac wounds, suppressing the elevated CM proliferation in injured grl mutant hearts. Our findings establish an injury-specific transcriptional repression program in governing CM renewal during heart regeneration, providing a potential strategy whereby silencing Grl repression at local regions might empower regeneration capacity to the injured mammalian heart.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors/genetics , Heart/physiology , Lysine/genetics , Methyltransferases/genetics , Regeneration/genetics , Transcription, Genetic/genetics , Vertebrates/genetics , Zebrafish Proteins/genetics , Animals , Animals, Newborn , Cell Differentiation/genetics , Cell Proliferation/genetics , Myocardium/metabolism , Myocytes, Cardiac/metabolism , Phosphorylation/genetics , STAT3 Transcription Factor/genetics , Signal Transduction/genetics , Zebrafish/genetics
8.
J Virol ; 96(18): e0102422, 2022 09 28.
Article in English | MEDLINE | ID: mdl-36037478

ABSTRACT

Zoonotic coronaviruses represent an ongoing threat to public health. The classical porcine epidemic diarrhea virus (PEDV) first appeared in the early 1970s. Since 2010, outbreaks of highly virulent PEDV variants have caused great economic losses to the swine industry worldwide. However, the strategies by which PEDV variants escape host immune responses are not fully understood. Complement component 3 (C3) is considered a central component of the three complement activation pathways and plays a crucial role in preventing viral infection. In this study, we found that C3 significantly inhibited PEDV replication in vitro, and both variant and classical PEDV strains induced high levels of interleukin-1ß (IL-1ß) in Huh7 cells. However, the PEDV variant strain reduces C3 transcript and protein levels induced by IL-1ß compared with the PEDV classical strain. Examination of key molecules of the C3 transcriptional signaling pathway revealed that variant PEDV reduced C3 by inhibiting CCAAT/enhancer-binding protein ß (C/EBP-ß) phosphorylation. Mechanistically, PEDV nonstructural protein 1 (NSP1) inhibited C/EBP-ß phosphorylation via amino acid residue 50. Finally, we constructed recombinant PEDVs to verify the critical role of amino acid 50 of NSP1 in the regulation of C3 expression. In summary, we identified a novel antiviral role of C3 in inhibiting PEDV replication and the viral immune evasion strategies of PEDV variants. Our study reveals new information on PEDV-host interactions and furthers our understanding of the pathogenic mechanism of this virus. IMPORTANCE The complement system acts as a vital link between the innate and the adaptive immunity and has the ability to recognize and neutralize various pathogens. Activation of the complement system acts as a double-edged sword, as appropriate levels of activation protect against pathogenic infections, but excessive responses can provoke a dramatic inflammatory response and cause tissue damage, leading to pathological processes, which often appear in COVID-19 patients. However, how PEDV, as the most severe coronavirus causing diarrhea in piglets, regulates the complement system has not been previously reported. In this study, for the first time, we identified a novel mechanism of a PEDV variant in the suppression of C3 expression, showing that different coronaviruses and even different subtype strains differ in regulation of C3 expression. In addition, this study provides a deeper understanding of the mechanism of the PEDV variant in immune escape and enhanced virulence.


Subject(s)
Complement C3 , Coronavirus Infections , Porcine epidemic diarrhea virus , Swine Diseases , Viral Nonstructural Proteins , Virus Replication , Animals , Antiviral Agents , COVID-19/immunology , Cell Line, Tumor , Complement C3/immunology , Coronavirus Infections/immunology , Coronavirus Infections/virology , Humans , Interleukin-1beta/genetics , Interleukin-1beta/immunology , Swine , Swine Diseases/immunology , Swine Diseases/virology , Viral Nonstructural Proteins/metabolism , Virus Replication/physiology
9.
Mutagenesis ; 37(3-4): 213-225, 2022 10 26.
Article in English | MEDLINE | ID: mdl-35869703

ABSTRACT

Two prototypical genotoxicants, benzo[a]pyrene (B[a]P) and colchicine (COL), were selected as model compounds to deduce their quantitative genotoxic dose-response relationship at low doses in a multi-endpoint genotoxicity assessment platform. Male Sprague-Dawley rats were treated with B[a]P (2.5-80 mg/kg bw/day) and COL (0.125-2 mg/kg bw/day) daily for 28 days. The parameters included were as follows: comet assay in the peripheral blood and liver, Pig-a gene mutation assay in the peripheral blood, and micronucleus test in the peripheral blood and bone marrow. A significant increase was observed in Pig-a mutant frequency in peripheral blood for B[a]P (started at 40 mg/kg bw/day on Day 14, started at 20 mg/kg bw/day on Day 28), whereas no statistical difference for COL was observed. Micronucleus frequency in reticulocytes of the peripheral blood and bone marrow increased significantly for B[a]P (80 mg/kg bw/day on Day 4, started at 20 mg/kg bw/day on Days 14 and 28 in the blood; started at 20 mg/kg bw/day on Day 28 in the bone marrow) and COL (started at 2 mg/kg bw/day on Day 14, 1 mg/kg bw/day on Day 28 in the blood; started at 1 mg/kg bw/day on Day 28 in the bone marrow). No statistical variation was found in indexes of comet assay at all time points for B[a]P and COL in the peripheral blood and liver. The dose-response relationships of Pig-a and micronucleus test data were analyzed for possible point of departures using three quantitative approaches, i.e., the benchmark dose, breakpoint dose, and no observed genotoxic effect level. The practical thresholds of the genotoxicity of B[a]P and COL estimated in this study were 0.122 and 0.0431 mg/kg bw/day, respectively, and our results also provided distinct genotoxic mode of action of the two chemicals.


Subject(s)
Benzo(a)pyrene , Colchicine , Rats , Animals , Male , Benzo(a)pyrene/toxicity , Colchicine/toxicity , Rats, Sprague-Dawley , Erythrocytes , Micronucleus Tests/methods , Comet Assay/methods , Reticulocytes , DNA Damage , Dose-Response Relationship, Drug , Mutagenicity Tests/methods
10.
J Appl Toxicol ; 41(4): 595-606, 2021 04.
Article in English | MEDLINE | ID: mdl-33067908

ABSTRACT

The micronucleus test (MNT) is the most widely applied short-term assay to detect clastogens or spindle disruptors. The use of flow cytometry (FCM) has been reported for micronucleated erythrocytes scoring in peripheral blood. The aim of this study was to develop a novel and practical protocol for MNT in rat peripheral blood by FCM, with the method validation. CD71-fluorescein isothiocyanate and DRAQ5 were adopted for the fluorescent staining of proteins and DNA, respectively, to detect micronuclei. To validate the method, groups of male Sprague-Dawley rats (five per group) received two oral gavage doses at 0 and 24 h of six chemicals (four positive mutagens: ethyl methanesulphonate [EMS], cyclophosphamide [CP], colchicine [COL], and ethyl nitrosourea [ENU]; two nongenotoxic chemicals: sodium saccharin and eugenol). Blood samples were collected from the tail vein before and on the five continuous days after treatments; all of which were analyzed for micronuclei presence by both the manual (Giemsa staining) and FCM methods. The FCM-based method consistently demonstrated highly sensitive responses for micronucleus detection at all concentrations and all time points for EMS, CP, COL, and ENU. Sodium saccharin and eugenol could be identified as negative in this protocol. Results obtained with the FCM-based method correlated well with the micronucleus frequencies (r = 0.659-0.952), and the proportion of immature erythrocytes (r = 0.915-0.981) tested by Giemsa staining. The method reported here, with easy operation, low background, and requirement for a regular FCM, could be an efficient system for micronucleus scoring.


Subject(s)
Flow Cytometry/methods , Leukocytes, Mononuclear/chemistry , Micronucleus Tests/methods , Mutagens/toxicity , Nitrosourea Compounds/toxicity , Reticulocytes , Animals , Colchicine/toxicity , Cyclophosphamide/toxicity , Ethyl Methanesulfonate/analogs & derivatives , Ethyl Methanesulfonate/toxicity , Eugenol/toxicity , Male , Rats , Rats, Sprague-Dawley , Saccharin/toxicity
11.
Microb Pathog ; 142: 104077, 2020 Feb 18.
Article in English | MEDLINE | ID: mdl-32084579

ABSTRACT

Alpha-linolenic acid (ALA), an important component of polyunsaturated fatty acids (PUFAs), possesses potent anti-inflammatory properties. To date, the effects of ALA on acute lung injury (ALI) remains unknown. This study was designed to investigate the potential protective effects of ALA on LPS-induced ALI and the underpinning mechanisms. An animal model of ALI was established via intratracheally injection of lipopolysaccharide (LPS, 1 mg/kg). We found that lung wet/dry weight ratio and protein concentration in Bronchoalveolar lavage fluid (BALF) were dramatically decreased by ALA pretreatment. Treatment with ALA significantly alleviated the infiltration of total cells and neutrophils, while increased the number of the macrophages. ALA significantly inhibited the secretion of proinflammatory cytokines including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1ß (IL-1ß) and increased anti-inflammatory cytokine. Moreover, we found that the levels of myeloperoxidase (MPO) and malondialdehyde (MDA) were highly increased in LPS-induced ALI, while the activities of glutathione (GSH) and superoxide dismutase (SOD) were decreased, which were reversed by ALA. ALA attenuated LPS-induced histopathological changes and apoptosis. Furthermore, ALA significantly inhibited the phosphorylation of IκBα and NF-κB (p65) activation in ALI. ALA showed anti-inflammatory effects in mice with LPS-induced ALI. NF-κB pathway may be involved in ALA mediated protective effects.

12.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(1): 67-73, 2020 Jan.
Article in Zh | MEDLINE | ID: mdl-31950792

ABSTRACT

OBJECTIVE: To develop and verify a flow cytometric measurement of reticulocytes (RETs) micronucleus in rat bone marrow. METHODS: In our flow cytometric protocol, reticulocytes, leukocytes and DNA were labeled by anti-CD71-fluorescein isothiocyanate (FITC), anti-CD45-phycoerythrin (PE) and DRAQ5, respectively. Sprague-Dawley (SD) rats were assigned to four treatment groups randomly, and were exposed to ethyl methanesulfonate (EMS), cyclophosphamide (CP), ethyl nitrosourea (ENU) and colchicine (COL) respectively. Each treatment group was divided into four subgroups (5 rats per subgroup) according to different exposure dosage. A exposure dose of 0 was used as vehicle control for each group. Rats were administered with testing mutagens by gavage twice with a 24 h interval. Bone marrow from both femurs were collected 24 h after the last administration. The frequency of micronucleated reticulocytes (MN-RETs) and the percentage of reticulocytes (RETs%) were determined by flow cytometric measurement established in this study. And the manual counting method with microscope (by Giemsa staining) was conducted at the same time. RESULTS: A method for detection of reticulocyte micronucleus in bone marrow based on flow cytometry was successfully established. The MN-RETs in rat bone marrow of 20 SD rats treated by vehicle (i.e., background value of MN-RETs) was 0.83‰±0.12‰ by this method. The background value of MN-RETs in manual enumeration method was 1.43‰±0.44‰. It was obvious that the flow cytometric method had lower background value and more stable results. The trend, in which MN-RETs ascended and RETs% descended with increasing dose, can be detected by both methods in rats that exposed to EMS, CP, ENU and COL. Both methods were good to detect the correlation of induced-MN-RETs with four testing mutagens (the correlation coefficients were ranged from 0.834 3 to 0.913 7). CONCLUSION: With its sensitivity, rapidity, easy operation and low background value, the three-color flow cytometric enumerative protocol established in our laboratory can be used as a good substitute for manual micronucleus counting method and used in genotoxicity assessment of chemical substances.


Subject(s)
Bone Marrow , Flow Cytometry , Reticulocytes , Animals , Micronucleus Tests , Rats , Rats, Sprague-Dawley , Reticulocytes/cytology
13.
Appl Microbiol Biotechnol ; 103(21-22): 8825-8838, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31637492

ABSTRACT

Microbial-induced CaCO3 precipitation has been widely applied in bacterial-based self-healing concrete. However, the limited biogenetic CaCO3 production by bacteria after they were introduced into the incompatible concrete matrix is a major challenge of this technology. In the present study, the potential of combining two metabolic pathways, urea hydrolysis and nitrate reduction, simultaneously in one bacteria strain for improving the bacterial CaCO3 yield has been investigated. One bacterial strain, Ralstonia eutropha H16, which has the highest Ca2+ tolerance and is capable of performing both urea hydrolysis and nitrate reduction in combined media was selected among three bacterial candidates based on the enzymatic examinations. Results showed that H16 does not need oxygen for urea hydrolysis and urease activity was determined primarily by cell concentration. However, the additional urea in the combined medium slowed down the nitrate reduction rate to 7 days until full NO3- decomposition. Moreover, the nitrate reduction of H16 was significantly restricted by an increased Ca2+ ion concentration in the media. Nevertheless, the overall CaCO3 precipitation yield can be improved by 20 to 30% after optimization through the combination of two metabolic pathways. The highest total CaCO3 precipitation yield achieved in an orthogonal experiment was 14 g/L. It can be concluded that Ralstonia eutropha H16 is a suitable bacterium for simultaneous activation of urea hydrolysis and nitrate reduction for improving the CaCO3 precipitation and it can be studied later, on activation of multiple metabolic pathways in bacteria-based self-healing concrete.


Subject(s)
Calcium Carbonate/metabolism , Cupriavidus necator/metabolism , Nitrates/metabolism , Urea/metabolism , Chemical Precipitation , Construction Materials/microbiology , Cupriavidus necator/enzymology , Hydrolysis
14.
Wei Sheng Yan Jiu ; 48(6): 976-1000, 2019 Nov.
Article in Zh | MEDLINE | ID: mdl-31875825

ABSTRACT

OBJECTIVE: This study was designed to determine the genotoxicity of 2-methylfuran based on a multi-endpoint genotoxicity test system. METHODS: The SPF-grade male SD rats(n = 30) were randomized to six treatment groups, i. e. 4 treatment groups(25, 50, 100 and 150 mg/kg), a control group(vegetable oil) and a positive groups(N-ethyl-N-nitrosourea, 80 mg/kg). All treatments were administrated by gavage for continuous 3 days. Tail vein blood for comet assay was collected at 3 h after the final administration. Pig-a gene mutation assays were performed on days 0(one day before gavage), 14 and 28. Micronucleus tests in peripheral blood using flow cytometry were performed on days 0 and 4. RESULTS: A statistically significant increase in tail intensity was observed at 150 mg/kg for peripheral blood in comet assay. There was no significant difference among the groups in mutant cell frequency of erythrocytes and reticulocytes at 2 timepoints in Pig-a gene mutation assay, and no significant difference among the groups in the frequency of micronucleus in micronucleus test. CONCLUSION: The result of genotoxicity tests suggested that 2-methylfuran was probably not mutagenic in vivo after acute exposure.


Subject(s)
Erythrocytes , Animals , Comet Assay , Furans , Male , Micronucleus Tests , Mutagenicity Tests , Rats , Rats, Sprague-Dawley
15.
Wei Sheng Yan Jiu ; 47(4): 525-553, 2018 Jul.
Article in Zh | MEDLINE | ID: mdl-30081975

ABSTRACT

OBJECTIVE: To make recommendations on the design and analysis of Piga gene mutation assay on the basis of the historical control data. METHODS: All negative historical control data( total: 128) were collected to create the historical control data base, and descriptive statistics was used to determine the distribution of the data. The power of the number of animals per group, number of measured cells per animal and number of groups were discussed through simulation test based on historical data base. RESULTS: The group mean of mutant red blood cells( RBCs~(CD59-)) and mutant reticulocytes ( RETs~(CD59-)) were 26. 63 × 10~(-6) and 35. 85 × 10~(-6), respectively, and the standard deviation were 27. 71 × 10~(-6) and 31. 06 × 10~(-6), respectively. By mapping the frequencies of data, the variables had skewed distributions and translated to normal distributions after logarithmic transformation. The confidence level for population means were 100% and 92% for RBCs( 1 × 10~6 cells per animal) and RETs( 0. 3 × 10~6 cells per animal), and it increased to 100% when 1 × 10~6 cells was scored for RETs. Group sizes of 5 had low statistical power while the minimal detectable difference was 2 times. The power had increased to > 80% when 4- or 5- fold of minimal detectable difference was employed. CONCLUSION: In brief, the recommendations include:① A log( 10) transformation of mutant frequencies often has been found satisfactory for data when parametric method such as an analysis of variance are used. ② Young adult animals( approximately 6 weeks of age rats) are recommended in this assay. ③ The recommended number of RETs and RBCs are > 1 × 10~6 and > 5 × 10~7, respectively. ④ Based on power calculations, 3 treatment groups and 1 negative control group are appropriate when fourfold increase was employed. ⑤ Group sizes of 6 or 7 are recommended but 5 analyzable animals per group may be acceptable when 4 test groups were used.


Subject(s)
Erythrocytes/drug effects , Membrane Proteins/genetics , Mutagens/toxicity , Mutation/genetics , Reticulocytes/drug effects , Animals , Erythrocytes/metabolism , Mutagenicity Tests/methods , Rats , Reticulocytes/metabolism
16.
J Surg Res ; 204(2): 288-296, 2016 08.
Article in English | MEDLINE | ID: mdl-27565063

ABSTRACT

BACKGROUND: CXCR3, a G-protein coupled chemokine receptor, has been shown to play a critical role in recruiting inflammatory cells into lungs in several studies. However, its roles in polymicrobial septic acute lung injury (ALI) is yet unknown. Therefore, the purpose of this study was to elucidate the protective effects of CXCR3 blockade on pulmonary microvascular endothelial cells (PMVECs) in septic ALI and explore potential mechanisms. MATERIALS AND METHODS: ALI was induced by polymicrobial sepsis through cecal ligation and puncture surgery. The expression of CXCR3 on pulmonary microvascular endothelial cells was measured 24 h after cecal ligation and puncture surgery. In addition, the protective effects of neutralizing antibody were detected, including protein concentration, inflammation cell counts, lung ​wet-to-dry ratio, and lung damages. In human umbilical vein endothelial cells (HUVECs) culture condition, CXCR3 expression was measured after exposure to tumor necrosis factor-α. The permeability and apoptosis ratio were detected through CXCR3 gene silencing on HUVECs. The p38 mitogen-activated protein kinase (MAPK) was analyzed with Western blot. RESULTS: CXCR3 expression was upregulated both in vivo and in vitro. After CXCR3 neutralizing antibody administrated intraperitoneally, the protein concentration, inflammatory cell counts in BALF and lung ​wet-to-dry ratio were decreased significantly, as well as the lung tissue damages. In vitro, CXCR3 gene silencing inhibited tumor necrosis factor-α and CXCL10-induced hyperpermeability and apoptosis in HUVECs. In addition, p38 mitogen-activated protein kinase activation was essential for CXCR3-mediated apoptosis. CONCLUSIONS: CXCR3 blockade exerts protective effects on ALI at least partly by inhibiting endothelial cells apoptosis and decreasing the leakage of protein-rich fluid and inflammatory cells. Blockade of CXCR3 may be a promising therapeutic strategy for severe sepsis-induced ALI.


Subject(s)
Acute Lung Injury/metabolism , Endothelial Cells/metabolism , Receptors, CXCR3/metabolism , Sepsis/complications , Acute Lung Injury/etiology , Acute Lung Injury/pathology , Acute Lung Injury/prevention & control , Animals , Apoptosis , Chemokine CXCL10/metabolism , Human Umbilical Vein Endothelial Cells , Humans , Lung/pathology , MAP Kinase Signaling System , Male , Mice, Inbred C57BL , Pulmonary Edema/etiology , Pulmonary Edema/metabolism , Receptors, CXCR3/antagonists & inhibitors , Tumor Necrosis Factor-alpha/metabolism
17.
RNA Biol ; 12(1): 82-91, 2015.
Article in English | MEDLINE | ID: mdl-25826415

ABSTRACT

BACKGROUND: Berberine (BBR) is a natural alkaloid derived from a traditional Chinese herbal medicine. However, the exact mechanisms underlying the different effects of berberine on MM cells have not been fully elucidated. METHODS: A systematic analysis assay integrated common signaling pathways modulated by the 3 miRNA clusters and mRNAs in MM cells after BBR treatment. The role of the mir-99a ∼ 125b cluster, an important oncomir in MM, was identified by comparing the effects of t-anti-mirs with complete complementary antisense locked nucleic acids (LNAs) against mature mir-125b (anti-mir-125b). RESULTS: Three miRNAs clusters (miR-99a ∼ 125b, miR-17 ∼ 92 and miR-106 ∼ 25) were significantly down-regulated in BBR-treated MM cells and are involved in multiple cancer-related signaling pathways. Furthermore, the top 5 differentially regulated genes, RAC1, NFκB1, MYC, JUN and CCND1 might play key roles in the progression of MM. Systematic integration revealed that 3 common signaling pathways (TP53, Erb and MAPK) link the 3 miRNA clusters and the 5 key mRNAs. Meanwhile, both BBR and seed-targeting t-anti-mir-99a ∼ 125b cluster LNAs significantly induced apoptosis, G2-phase cell cycle arrest and colony inhibition. CONCLUSIONS: our results suggest that BBR suppresses multiple myeloma cells, partly by down-regulating the 3 miRNA clusters and many mRNAs, possibly through TP53, Erb and MAPK signaling pathways. The mir-99a ∼ 125b cluster might be a novel target for MM treatment. These findings provide new mechanistic insight into the anticancer effects of certain traditional Chinese herbal medicine compounds.


Subject(s)
Alkaloids/pharmacology , Berberine/pharmacology , MicroRNAs/metabolism , Multiple Myeloma/metabolism , RNA, Messenger/metabolism , Signal Transduction/drug effects , Cell Line, Tumor , G2 Phase Cell Cycle Checkpoints , Humans , Multiple Myeloma/pathology , Oligoribonucleotides, Antisense/metabolism
18.
Int J Gynaecol Obstet ; 164(1): 86-98, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37337776

ABSTRACT

OBJECTIVE: To assess the association between interpregnancy interval (IPI) and gestational diabetes mellitus (GDM). METHODS: Data of this retrospective cohort study were obtained from the National Vital Statistics System (NVSS) 2020. The participants were divided into different groups according to different IPI (<6, 6-11, 12-17, 18-23, 24-59 (reference), 60-119, ≥120 months). Multivariate logistic models were constructed to evaluate the association between IPI and GDM. Subgroup analysis was further performed. RESULTS: A total of 1 515 263 women were included, with 123 951 (8.18%) having GDM. Compared with the 24-59 months group, the <6 months (odds ratio [OR] 0.64, 95% confidence interval [CI] 0.46-0.90, P = 0.009), 12-17 months (OR 0.96, 95% CI 0.94-0.98, P < 0.001), and 18-23 months (OR 0.94, 95% CI 0.93-0.96, P < 0.001) groups had a significantly lower risk of GDM, while the 60-119 months (OR 1.13, 95% CI 1.11-1.15, P < 0.001) and ≥120 months (OR 1.18, 95% CI 1.15-1.21, P < 0.001) groups had a significantly higher risk of GDM. No significant difference was observed in the risk of GDM between the 6-11 and 24-59 months groups (P = 0.542). The PI-GDM association varied across different groups of age, pre-pregnancy body mass index, pre-pregnancy smoking status, history of cesarean section, history of preterm birth, prior terminations, and parity. CONCLUSION: An IPI of 18-23 months may be a better interval than 24-59 months in managing the risk of GDM.


Subject(s)
Diabetes, Gestational , Premature Birth , Pregnancy , Infant, Newborn , Female , Humans , Diabetes, Gestational/epidemiology , Cohort Studies , Cesarean Section , Retrospective Studies , Birth Intervals , Premature Birth/epidemiology , Body Mass Index , Risk Factors
19.
Risk Manag Healthc Policy ; 17: 549-557, 2024.
Article in English | MEDLINE | ID: mdl-38496372

ABSTRACT

Purpose: Coronary artery disease (CAD) patients frequently face readmissions due to suboptimal disease management. Prediction models are pivotal for detecting early unplanned readmissions. This review offers a unified assessment, aiming to lay the groundwork for enhancing prediction models and informing prevention strategies. Methods: A search through five databases (PubMed, Web of Science, EBSCOhost, Embase, China National Knowledge Infrastructure) up to September 2023 identified studies on prediction models for coronary artery disease patient readmissions for this review. Two independent reviewers used the CHARMS checklist for data extraction and the PROBAST tool for bias assessment. Results: From 12,457 records, 15 studies were selected, contributing 30 models targeting various CAD patient groups (AMI, CABG, ACS) from primarily China, the USA, and Canada. Models utilized varied methods such as logistic regression and machine learning, with performance predominantly measured by the c-index. Key predictors included age, gender, and hospital stay duration. Readmission rates in the studies varied from 4.8% to 45.1%. Despite high bias risk across models, several showed notable accuracy and calibration. Conclusion: The study highlights the need for thorough external validation and the use of the PROBAST tool to reduce bias in models predicting readmission for CAD patients.

20.
Virology ; 597: 110130, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38850894

ABSTRACT

Porcine rotavirus (PoRV) is one of the main pathogens causing diarrhea in piglets, and multiple genotypes coexist. However, an effective vaccine is currently lacking. Here, the potential adjuvant of nonstructural protein 4 (NSP4) and highly immunogenic structural protein VP4 prompted us to construct recombinant NSP486-175aa (NSP4*) and VP426-476aa (VP4*) proteins, combine them as immunogens to evaluate their efficacy. Results indicated that NSP4* enhanced systemic and local mucosal responses induced by VP4*. The VP4*-IgG, VP4*-IgA in feces and IgA-secreting cells in intestines induced by the co-immunization were significantly higher than those induced by VP4* alone. Co-immunization of NSP4* and VP4* also induced strong cellular immunity with significantly increased IFN-λ than the single VP4*. Summarily, the NSP4* as a synergistical antigen exerted limited effects on the PoRV NAbs elevation, but conferred strong VP4*-specific mucosal and cellular efficacy, which lays the foundation for the development of a more effective porcine rotavirus subunit vaccine.

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