RESUMO
Lipid metabolism reprogramming stands as a fundamental hallmark of cancer cells. Unraveling the core regulators of lipid biosynthesis holds the potential to find promising therapeutic targets in pancreatic ductal adenocarcinoma (PDAC). Here, it is demonstrated that platelet-derived growth factor C (PDGFC) orchestrated lipid metabolism, thereby facilitated the malignant progression of PDAC. Expression of PDGFC is upregulated in PDAC cohorts and is corelated with a poor prognosis. Aberrantly high expression of PDGFC promoted proliferation and metastasis of PDAC both in vitro and in vivo. Mechanistically, PDGFC accelerated the malignant progression of PDAC by upregulating fatty acid accumulation through sterol regulatory element-binding protein 1 (SREBP1), a key transcription factor in lipid metabolism. Remarkably, Betulin, an inhibitor of SREBP1, demonstrated the capability to inhibit proliferation and metastasis of PDAC cell lines, along with attenuating the process of liver metastasis in vivo. Overall, the study underscores the pivotal role of PDGFC-mediated lipid metabolism in PDAC progression, suggesting PDGFC as a potential biomarker for PDAC metastasis. Targeting PDGFC-induced lipid metabolism emerges as a promising therapeutic strategy for metastatic PDAC, with the potential to improve clinical outcomes.
RESUMO
ABSTRACT: The precise movement of the maxilla is particularly important for orthognathic surgery, especially for patients with maxillary segmentation. In this preliminary study, the authors present a new tooth bone combined with a supporting osteotomy guide and positioning guide to guide the osteotomy and reduction of the maxilla. Through our preoperative simulation and postoperative image fusion, the authors found that the overlapping area is more than 90%. According to compare of the virtual plans and the postoperative results based on distances from the maxillary land- marks to the horizontal plane, sagittal plane, and coronal plane, the surgical error was about 2mm. Our T-shaped guide provides a reliable method for patients with maxillary segmental osteotomy, which may be a useful alternative to the intermediate.
Assuntos
Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Placas Ósseas , Humanos , Imageamento Tridimensional/métodos , Maxila/cirurgia , Procedimentos Cirúrgicos Ortognáticos/métodos , Osteotomia de Le Fort/métodosRESUMO
Unmanned aerial vehicle (UAV) multispectral remote sensing can be used to monitor multiple water quality parameters, such as suspended solids, turbidity, total phosphorus, and chlorophyll. Establishing a stable and accurate water quality parameter inversion model is a prerequisite for this work. The matching pixel-by-pixel (MPP) algorithm is an inversion algorithm for high resolution features of UAV images; however, it is associated with problems of excessive computation and over-fitting. To overcome these problems, the optimize-MPP (OPT-MPP) algorithm is proposed. In this study, Qingshan Lake in Hangzhou City, Zhejiang Province, was used as the research area. Forty-five samples were collected to construct the OPT-MPP algorithm inversion model for two water quality parameters:the suspended sediments concentration (SS) and turbidity (TU). The results showed that the optimal suspended sediment concentration inversion model had a determination coefficient (R2) of 0.7870 and a comprehensive error of 0.1308. The optimal turbidity inversion model had a R2 of 0.8043 and a comprehensive error of 0.1503. Hence, the inversion of the spatial distribution information for water quality parameters in each experimental area of QingShan Lake was realized by using the optimal models of the two established parameters.
Assuntos
Tecnologia de Sensoriamento Remoto , Qualidade da Água , Algoritmos , Clorofila , LagosRESUMO
Live-attenuated influenza vaccines (LAIVs) are now available for the prevention of influenza, with LAIV strains generally derived from serial passage in cultures or by reverse genetics (RG). The receptor-binding domain (RBD) in haemagglutinin (HA) of influenza virus is responsible for viral binding to the avian-type 2,3-α-linked or human-type 2,6-α-linked sialic acid receptor; however, the virulence determinants in the RBD of H5N1 virus remain largely unknown. In the present study, serial passage of H5N1 virus A/Vietnam/1194/2004 in Madin-Darby canine kidney cells resulted in the generation of adapted variants with large-plaque morphology, and genomic sequencing of selected variants revealed two specific amino acid substitutions (K193E and G225E) in the RBD. RG was used to generate H5N1 viruses containing either single or double substitutions in HA. The RG virus containing K193E and G225E mutations (rVN-K193E/G225E) demonstrated large-plaque morphology, enhanced replication and genetic stability after serial passage, without changing the receptor-binding preference. Importantly, in vivo virulence assessment demonstrated that rVN-K193E/G225E was significantly attenuated in mice. Microneutralization and haemagglutination inhibition assays demonstrated that immunization with rVN-K193E/G225E efficiently induced a robust antibody response against WT H5N1 virus in mice. Taken together, our experiments demonstrated that K193E and G225E mutations synergistically attenuated H5N1 virus without enhancing the receptor-binding avidity, and that the RG virus rVN-K193E/G225E represents a potential H5N1 LAIV strategy that deserves further development. These findings identify the RBD as a novel attenuation target for live vaccine development and highlight the complexity of RBD interactions.
Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Virus da Influenza A Subtipo H5N1/genética , Vacinas contra Influenza/genética , Vacinas contra Influenza/imunologia , Influenza Humana/virologia , Mutação de Sentido Incorreto , Animais , Anticorpos Antivirais , Cães , Feminino , Glicoproteínas de Hemaglutininação de Vírus da Influenza/administração & dosagem , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Humanos , Imunização , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/química , Influenza Humana/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Terciária de Proteína , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/química , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vacinas ViraisAssuntos
Adenocarcinoma/diagnóstico , Adenocarcinoma/secundário , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/secundário , Neoplasias da Bexiga Urinária/complicações , Neoplasias Urogenitais/diagnóstico , Neoplasias Urogenitais/secundário , Adenocarcinoma/cirurgia , Cistectomia , Humanos , Masculino , Pessoa de Meia-Idade , Pênis/cirurgia , Escroto/cirurgia , Neoplasias Cutâneas/cirurgia , Resultado do Tratamento , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/secundário , Neoplasias da Bexiga Urinária/cirurgia , Neoplasias Urogenitais/cirurgiaRESUMO
UNLABELLED: Over the course of two waves of infection, H7N9 avian influenza A virus has caused 436 human infections and claimed 170 lives in China as of July 2014. To investigate the prevalence and genetic diversity of H7N9, we surveyed avian influenza viruses in poultry in Jiangsu province within the outbreak epicenter. We found frequent occurrence of H7N9/H9N2 coinfection in chickens. Molecular clock phylogenetic analysis confirms coinfection by H7N9/H9N2 viruses and also reveals that the identity of the H7N9 outbreak lineage is confounded by ongoing reassortment between outbreak viruses and diverse H9N2 viruses in domestic birds. Experimental inoculation of a coinfected sample in cell culture yielded two reassortant H7N9 strains with polymerase segments from the original H9N2 strain. Ongoing reassortment between the H7N9 outbreak lineage and diverse H9N2 viruses may generate new strains with the potential to infect humans, highlighting the need for continued viral surveillance in poultry and humans. IMPORTANCE: We found frequent occurrence of H7N9/H9N2 coinfection in chickens. The H7N9 outbreak lineage is confounded by ongoing reassortment between H7N9 and H9N2 viruses. The importance of H9N2 viruses as the source of novel avian influenza virus infections in humans requires continuous attention.
Assuntos
Coinfecção/veterinária , Subtipo H7N9 do Vírus da Influenza A/isolamento & purificação , Vírus da Influenza A Subtipo H9N2/isolamento & purificação , Influenza Aviária/virologia , Vírus Reordenados/isolamento & purificação , Animais , China/epidemiologia , Coinfecção/epidemiologia , Coinfecção/virologia , Evolução Molecular , Subtipo H7N9 do Vírus da Influenza A/genética , Vírus da Influenza A Subtipo H9N2/genética , Influenza Aviária/epidemiologia , Epidemiologia Molecular , Aves Domésticas , Vírus Reordenados/genéticaRESUMO
OBJECTIVE: To investigate the recent emerged endemic region of tick-borne encephalitis (TBE) regarding its natural reserves, in Charles Hilary, northern Xinjiang and to isolate and characterize the viral geographic strain. METHODS: Using indirect fluorescent assay to detect tick-borne encephalitis virus (TBEV) specific IgG antibodies from serum of local residents including 2 unconfirmed viral encephalitis patients in 2011 spring-summer. Viruses were isolated from tick samples by inoculating BALB/c mice and BHK-21 cells. For phylogenetic analysis. TBEV NS1 gene fragments were detected by RT-PCR and then subjected to sequence alignment. RESULTS: 1760 ticks were captured from the fields to have found that Ixodes persulcatus were dominated among the tick population. Two viral encephalitis patients were diagnosed as TBEV infection. In addition, 35.4% (23/65) local residents were detected positive for presence of TBEV specific-IgG antibodies in serum. After inoculation, morbidity and mortality of BALB/c mice were 72.9% (70/96) and 55.7% (44/79), respectively. TBEV specific-fragments were amplified from brain tissue of dead mice and cells culture supernatant. NS1 sequence alignment showed that the viral isolates were clustered into TBEV far-eastern sub-type, phylogenetically, and were mostly close to the isolates from northeastern China (99%) and Russian strain (98%). CONCLUSION: In this study, a new endemic loci of TBE was firstly described in Charles Hilary natural reserve, northern Xinjiang. TBEV geographic isolates belonged to TBEV far-eastern subtype while Ixodes persulcatus and Dermacentor silvarum played crucial roles for disease transition.
Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/genética , Encefalite Transmitida por Carrapatos/epidemiologia , Encefalite Transmitida por Carrapatos/transmissão , Adulto , Animais , China/epidemiologia , Vírus da Encefalite Transmitidos por Carrapatos/imunologia , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Encefalite Transmitida por Carrapatos/virologia , Feminino , Humanos , Masculino , Camundongos , RNA Viral/genéticaRESUMO
Amur virus (AMRV) is a member of the genus Hantavirus in the family Bunyaviridae. In this study, we determined for the first time the complete genome sequence of the AMRV H8205 strain, which was isolated from a patient with hemorrhagic fever with renal syndrome (HFRS) in China. The complete nucleotide sequence of the S segment of AMRV H8205 is 1699 nt long, with a 5' noncoding region (5'NC) of 36 nt, followed by a coding sequence of 1290 nt and a 3'NC of 373 nt. The complete sequence of the M segment is 3615 nt long, with a 5'NC of 40 nt, followed by a coding sequence of 3408 nt and a 3'NC of 167 nt. The complete sequence of the L segment is 6536 nt long, with a 5'NC of 37 nt, followed by a coding sequence of 6453 nt and a 3'NC of 40 nt. The major open reading frame (ORF) of each of the three segments (S, nt 37-1326; M, nt 41-3445; L, nt 38-6490) has a coding capacity of 430 aa, 1135 aa, 2151 aa, respectively. Phylogenetic analysis of the nucleotide sequences using the NJ method indicated that H8205 virus, together with the Amur strains isolated from Far-Eastern Russia and Korea, forms a well-supported lineage. Our results will provide insights into the genetic diversity of hantaviruses (HNTV).
Assuntos
Bunyaviridae/classificação , Bunyaviridae/genética , Genoma Viral , Animais , China , Chlorocebus aethiops , Dados de Sequência Molecular , Filogenia , Células VeroRESUMO
The present paper outlined pesticide registration status for traditional Chinese medicines (TCMs) and summarized the characteristics of pesticide contamination in different regions of some widely used TCMs by retrieving last 10 years' literatures. At present, the problems of pesticide residues for TCM include less pesticide registrations, widespread high-residue organochlorine pesticides contamination, pesticide abuse, irregular GAP bases and imperfect pesticide limit standards, etc. According to the current situation, we should adopt some control measures to strengthen the quality control of TCMs so as to ensure the safety of TCMs and related products.
Assuntos
Contaminação de Medicamentos/estatística & dados numéricos , Medicina Tradicional Chinesa/métodos , Resíduos de Praguicidas/análise , Animais , China , Contaminação de Medicamentos/prevenção & controle , Humanos , Sistema de RegistrosRESUMO
In this study, the complete genomic nucleotide sequence of Chikungunya virus (CHIKV) strain S27 African prototype was determined and three 21 nucleotides repeated sequence elements (RSEs) at positions 11398-11418, 11533-11553, and 11620-11640 in the 3' untranslated region (3'UTR) were confirmed. In addition, the 3'UTRs of all CHIKV strains deposited in GenBank were analyzed. The results displayed that the majority of the CHIKV strains consisted of the three 21 nucleotides RSEs in the 3'UTRs, and the third RSE was the most conservative. The conservation of the three RSEs of 21 nucleotides within the 3'UTR of CHIKV genome may play an important role on the virus replication cycle.
Assuntos
Regiões 3' não Traduzidas , Vírus Chikungunya/genética , Genoma Viral , RNA Viral/genética , Sequências Repetitivas de Ácido Nucleico , Análise de Sequência de DNA , Infecções por Alphavirus/epidemiologia , Infecções por Alphavirus/virologia , Febre de Chikungunya , Vírus Chikungunya/isolamento & purificação , Surtos de Doenças , Humanos , Dados de Sequência Molecular , Tanzânia/epidemiologiaRESUMO
Tick-borne encephalitis (TBEV) is prevalent over a wide area of the Eurasian continent. TBE viruses cause severe encephalitis in humans, with serious sequelae, and have a significant impact on public health in these endemic regions. To gain insight into genetic evolution of tick-borne encephalitis virus (TBEV) in China, the complete genomic sequences of two TBEV strains Senzhang and MDJ01, which were isolated in 1953 and 2001 respectively, were characterized. The complete genome sequences of two strains were all consist 10,784 nucleotides and there are 364 nucleotides deletion in the 3' nontranslated region. Compared with other TBEV strains, homology range from 85.2% (Zausaev) to 99.6% (MDJ02 and MDJ03) on the level of nucleotide. Phylogenetic trees based on the complete genome, open reading frame and E gene nucleotide sequences all showed that the strains Senzhang and MDJ01 belong to Far-Eastern subtype and cluster with other Chinese TBEV strains. All these implied that TBEVs prevalent in China were highly conservative, other measurement should be taken to improve protective efficacy of present vaccine.
Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/genética , Genoma Viral , RNA Viral/genética , Análise de Sequência de DNA , China , Análise por Conglomerados , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Humanos , Dados de Sequência Molecular , Filogenia , Deleção de Sequência , Homologia de Sequência do Ácido NucleicoRESUMO
West Nile virus (WNV) non-structural protein 1 (NS1) elicits protective immune responses during infection of animals. WNV NS1-specific antibody responses can provide the basis for serological diagnostic reagents, so the antigenic sites in NS1 that are targeted by host immune responses need to be identified and the conservation of these sites among the Japanese encephalitis virus (JEV) serocomplex members also needs to be defined. The present study describes the mapping of linear B-cell epitopes in WNV NS1. We screened eight NS1-specific mAbs and antisera (polyclonal antibodies; pAbs) from mice immunized with recombinant NS1 for reactivity against 35 partially overlapping peptides covering the entire WNV NS1. The screen using mAbs identified four WNV-specific (including Kunjin virus) epitopes, located at aa 21-36, 101-116, 191-206 and 261-276 in WNV NS1. However, using pAbs, only three WNV-specific epitopes were identified, located at positions 101-116, 191-206 and 231-246. Two of these epitopes (aa 21-36 and 261-276) had different reactivity with mAbs and pAbs. The knowledge and reagents generated in this study have potential applications in differential diagnostics and epitope-based marker vaccine development for WNV and viruses of the JEV serocomplex.
Assuntos
Vírus da Encefalite Japonesa (Espécie)/imunologia , Encefalite Japonesa/virologia , Mapeamento de Epitopos , Epitopos de Linfócito B/imunologia , Proteínas não Estruturais Virais/imunologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/imunologia , Linhagem Celular , Vírus da Encefalite Japonesa (Espécie)/química , Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/imunologia , Epitopos de Linfócito B/química , Epitopos de Linfócito B/genética , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Alinhamento de Sequência , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética , Febre do Nilo Ocidental/imunologia , Vírus do Nilo Ocidental/química , Vírus do Nilo Ocidental/genéticaRESUMO
BACKGROUND: The West Nile virus (WNV) nonstructural protein 1 (NS1) is an important antigenic protein that elicits protective antibody responses in animals and can be used for the serological diagnosis of WNV infection. Although previous work has demonstrated the vital role of WNV NS1-specific antibody responses, the specific epitopes in the NS1 have not been identified. RESULTS: The present study describes the identification of two linear B-cell epitopes in WNV NS1 through screening a phage-displayed random 12-mer peptide library with two monoclonal antibodies (mAbs) 3C7 and 4D1 that directed against the NS1. The mAbs 3C7 and 4D1 recognized phages displaying peptides with the consensus motifs LTATTEK and VVDGPETKEC, respectively. Exact sequences of both motifs were found in the NS1 ((895)LTATTEK(901) and (925)VVDGPETKEC(934)). Further identification of the displayed B cell epitopes were conducted using a set of truncated peptides expressed as MBP fusion proteins. The data indicated that (896)TATTEK(901) and (925)VVDGPETKEC(934) are minimal determinants of the linear B cell epitopes recognized by the mAbs 3C7 and 4D1, respectively. Antibodies present in the serum of WNV-positive horses recognized the minimal linear epitopes in Western blot analysis, indicating that the two peptides are antigenic in horses during infection. Furthermore, we found that the epitope recognized by 3C7 is conserved only among WNV strains, whereas the epitope recognized by 4D1 is a common motif shared among WNV and other members of Japanese encephalitis virus (JEV) serocomplex. CONCLUSIONS: We identified TATTEK and VVDGPETKEC as NS1-specific linear B-cell epitopes recognized by the mAbs 3C7 and 4D1, respectively. The knowledge and reagents generated in this study may have potential applications in differential diagnosis and the development of epitope-based marker vaccines against WNV and other viruses of JEV serocomplex.
Assuntos
Epitopos de Linfócito B/imunologia , Biblioteca de Peptídeos , Proteínas não Estruturais Virais/imunologia , Vírus do Nilo Ocidental/imunologia , Animais , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Antivirais/sangue , Western Blotting , Epitopos de Linfócito B/genética , Doenças dos Cavalos/imunologia , Cavalos , Programas de Rastreamento , Camundongos , Camundongos Endogâmicos BALB C , Proteínas não Estruturais Virais/genética , Febre do Nilo Ocidental/imunologia , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/genéticaRESUMO
BACKGROUND: The West Nile virus (WNV) capsid (C) protein is one of the three viral structural proteins, encapsidates the viral RNA to form the nucleocapsid, and is necessary for nuclear and nucleolar localization. The antigenic sites on C protein that are targeted by humoral immune responses have not been studied thoroughly, and well-defined B-cell epitopes on the WNV C protein have not been reported. RESULTS: In this study, we generated a WNV C protein-specific monoclonal antibody (mAb) and defined the linear epitope recognized by the mAb by screening a 12-mer peptide library using phage-display technology. The mAb, designated as 6D3, recognized the phages displaying a consensus motif consisting of the amino acid sequence KKPGGPG, which is identical to an amino acid sequence present in WNV C protein. Further fine mapping was conducted using truncated peptides expressed as MBP-fusion proteins. We found that the KKPGGPG motif is the minimal determinant of the linear epitope recognized by the mAb 6D3. Western blot (WB) analysis demonstrated that the KKPGGPG epitope could be recognized by antibodies contained in WNV- and Japanese encephalitis virus (JEV)-positive equine serum, but was not recognized by Dengue virus 1-4 (DENV1-4)-positive mice serum. Furthermore, we found that the epitope recognized by 6D3 is highly conserved among the JEV serocomplex of the Family Flaviviridae. CONCLUSION: The KKPGGPG epitope is a JEV serocomplex-specific linear B-cell epitope recognized by the 6D3 mAb generated in this study. The 6D3 mAb may serve as a novel reagent in development of diagnostic tests for JEV serocomplex infection. Further, the identification of the B-cell epitope that is highly conserved among the JEV serocomplex may support the rationale design of vaccines against viruses of the JEV serocomplex.
Assuntos
Anticorpos Monoclonais/análise , Proteínas do Capsídeo/química , Sequência Conservada , Vírus da Encefalite Japonesa (Espécie)/química , Epitopos de Linfócito B/química , Biblioteca de Peptídeos , Vírus do Nilo Ocidental/química , Sequência de Aminoácidos , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Vírus da Encefalite Japonesa (Espécie)/genética , Vírus da Encefalite Japonesa (Espécie)/imunologia , Encefalite Japonesa/imunologia , Encefalite Japonesa/virologia , Mapeamento de Epitopos , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Humanos , Dados de Sequência Molecular , Alinhamento de Sequência , Febre do Nilo Ocidental/imunologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/genética , Vírus do Nilo Ocidental/imunologiaRESUMO
A duplex real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay was improved for simultaneous detection of highly pathogenic H5N1 avian influenza virus and pandemic H1N1 (2009) influenza virus, which is suitable for early diagnosis of influenza-like patients and for epidemiological surveillance. The sensitivity of this duplex real-time RT-PCR assay was 0.02 TCID50 (50% tissue culture infective dose) for H5N1 and 0.2 TCID50 for the pandemic H1N1, which was the same as that of each single-target RT-PCR for pandemic H1N1 and even more sensitive for H5N1 with the same primers and probes. No cross reactivity of detecting other subtype influenza viruses or respiratory tract viruses was observed. Two hundred and thirty-six clinical specimens were tested by comparing with single real-time RT-PCR and result from the duplex assay was 100% consistent with the results of single real-time RT-PCR and sequence analysis.
Assuntos
Surtos de Doenças , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Virus da Influenza A Subtipo H5N1/isolamento & purificação , Influenza Humana/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Animais , Linhagem Celular , Primers do DNA/genética , Cães , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Virus da Influenza A Subtipo H5N1/genética , Influenza Humana/epidemiologia , CamundongosRESUMO
To develop colloidal gold immunochromatographic strips for the direct detection of the Streptococcus suis serotype 2 antigen, colloidal gold was prepared by reduction of a gold salt with sodium citrate and coupled with polyclonal antibody against S. suis serotype 2. The optimal concentrations of the capture antibody and the coating antibody were determined to be 22mug/mL and 2.0mg/mL, respectively, and that of the blocking buffer was determined to be 1.5% bovine serum albumin. Different serotypes of S. suis and other related bacteria were used to evaluate the sensitivity, specificity, and stability of the immunochromatographic strips. The detection sensitivity was found to be as high as 10(6)CFU/mL. There was no cross-reaction of the antibodies with other serotypes of S. suis (except with SS1/2, which shares some common sugar residues or antigenic determinants with serotype 2) and other related bacteria. In conclusion, we developed colloidal gold immunochromatographic strips that had high sensitivity and specificity. This method proved to be feasible, convenient, rapid, and effective for detecting S. suis serotype 2.
Assuntos
Cromatografia/métodos , Imunoensaio/métodos , Infecções Estreptocócicas/veterinária , Streptococcus suis/isolamento & purificação , Doenças dos Suínos/diagnóstico , Animais , Anticorpos Antibacterianos , Bovinos , Coloide de Ouro , Sorotipagem/métodos , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/microbiologia , Streptococcus suis/classificação , Streptococcus suis/imunologia , Suínos/microbiologia , Doenças dos Suínos/microbiologiaRESUMO
BACKGROUND: To express the prM-E protein in Sf9 cells, and lay a basis for further study on the function of the viral proteins and development of specific diagnostic reagents. METHODS: The recombinant prM-E protein of tick-borne encephalitis virus was expressed in insect cell Sf9 by RT-PCR amplification of prM-E gene, construction of donor plasmid of Bac-to-Bac baculovirus expression system, homologous recombination of donor plasmid with bacmid DNA at the site of Tn7 and transfection of insect cell Sf9. RESULTS: Recombinant subviral particles, about 30 nm in diameter, consisting of prM-E were observed by electron microscope in the supernatant of infected cells, which indicated that infected cells released virus-like particles (VLPs) into the culture medium. The results of Western-blot and the indirect immunofluorescence assay (IFA) showed that the recombinant proteins retained antigenic and conformational structures similar to those of native virus proteins. Using the recombinant prM-E as antigens to detect samples of patient sera by ELISA and IFA, all of 16 sera from patients with tick-borne encephalitis were positive and all of 6 sera from other patients were negative. CONCLUSION: The prM-E protein expressed in insect cells retains good antigenicity.
Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/genética , Proteínas do Envelope Viral/genética , Animais , Western Blotting , Linhagem Celular , Técnica Indireta de Fluorescência para Anticorpo , Regulação Viral da Expressão Gênica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Spodoptera , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/metabolismoRESUMO
To screen small animals susceptible to SARS-CoV, five species of animals, including guinea pig, hamster, albino hamster, chicken and rat, were experimentally infected with SARS-CoV strain BJ-01 by different routes. On the basis of this, further cynomolgus and rhesus macaques were selected and experimentally inoculated SARS-CoV, the quality they serve as animal model for SARS was evaluated. The results showed that, all five species of small animals chosed were not susceptible to SARS-CoV, no characterized changes in clinical sign and histopathology were observed after infection, but from the lung samples of large rat and pig guinea, the genomic RNA of SARS-CoV could be detected by RT-PCR at day 14 post infection, this suggested that SARS-CoV could replicate in these animals. After inoculated with SARS-CoV, all inoculated cynomolgus and rhesus macaques had developed interstitial pneumonia of differing severity. These changes on histopathology were similar to that seen in SARS patients, but the pathological lesions were less severe than that of human. Except interstitial pneumonia, no other characterized pathological changes were observed. This suggested cynomolgus and rhesus macaques were not the ideal animal model for SARS in fact, but they could serve as animal model for SARS when a more ideal animal model is absent.
Assuntos
Modelos Animais de Doenças , Síndrome Respiratória Aguda Grave/virologia , Animais , Galinhas , Humanos , Macaca fascicularis , Macaca mulatta , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Síndrome Respiratória Aguda Grave/patologia , Replicação ViralRESUMO
AIM: To investigate the expression of phosphorylating p38 mitogen-activated protein kinase (MAPK) in rat small intestine after ischemia-reperfusion (I/R) insult and its relationship with the localization of intestinal stem cells. METHODS: Forty-eight Wistar rats were divided randomly into three groups, namely intestinal ischemia-reperfusion group (R), intestinal ischemia group (I) and sham-operated control group (C). In group I, the animals were killed 45 minutes after superior mesenteric artery (SMA) occlusion, while in group R the rats sustained SMA occlusion for 45 minutes and reperfusion for 2, 6, 12 or 24 hours respectively. In sham-operated control group, SMA was separated, but without occlusion. The activity of plasma diamine oxidase (DAO) was determined. Intestinal tissue samples were also taken for histological analysis and immunohistochemical analysis of MAPK p38 detection and intestinal stem cell localization. RESULTS: The changes in histological structure and plasma DAO levels indicated that the intestinal barrier was damaged after intestinal I/R injury. In group C and I, each crypt contained 5-6 p38 MAPK positive cells, which were mainly located in the lower region of the crypts. This was consistent with the distribution of intestinal stem cells. The presence of positive cells in crypts increased with the time of reperfusion and reached its peak at 12 hours after reperfusion (35.6 %). CONCLUSION: After intestinal I/R injury, the expression of phosphorylating-p38 MAPK in small intestine increased with the duration of reperfusion, and its distribution coincided with that of intestinal stem cells and their daughter cells, indicating that phosphorylating-p38 might be a possible marker of intestinal stem cells.
Assuntos
Intestino Delgado/irrigação sanguínea , Intestino Delgado/enzimologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/patologia , Células-Tronco/patologia , Animais , Ativação Enzimática , Intestino Delgado/patologia , Masculino , Fosforilação , Ratos , Ratos Wistar , Proteínas Quinases p38 Ativadas por MitógenoRESUMO
OBJECTIVE: To investigate the expression characteristics of protooncogene c-jun and its related gene p38 in different developmental intestinal epithelial cells in rats, and to explore their biological roles in the intestinal wound healing after injury. METHODS: Immunohistochemical techniques were used to detect the expressions of c-jun, p38 and proliferating cell nuclear antigen (PCNA). RESULTS: The positive expression of c-jun in intestinal epithelial cells at the early development stage (from E14 d to P28 d) was much stronger and more extensive than that in mature rats, and migrated from bottom to top of villus with epithelial cellular development. The positive expression of PCNA was similar with c-jun during the same time, but the distinction between them was location of their expression. The expression of c-jun in mature rat only lay in the top of villus, while the expression of PCNA was limited to intestinal crypts. The expression of p38 during stages of development and mature, mainly was in mitogenic cells. CONCLUSION: The results indicate that the strong expression of tumor gene c-jun at the early development and mature stages of intestinal epithelial cells at the special region is related to cellular differentiation, and p38 is probable correlate with cellular mitogenesis.