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1.
Acta Biomater ; 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34775123

RESUMO

Bacterial resistance to antibiotics have become one of the most severe threats in global public health, so the development of new-style antimicrobial agents is urgent. In this work, quaternized carbon quantum dots (qCQDs) with broad-spectrum antibacterial activity were synthesized by a simple green "one-pot" method using dimethyl diallyl ammonium chloride and glucose as reaction precursors. The qCQDs displayed satisfactory antibacterial activity against both Gram-positive and gram-negative bacteria. In rat models of wounds infected with mixed bacteria, qCQDs obviously restored the weight of rats, significantly reduced the death of rats from severe infection, and promoted the recovery and healing of infected wounds. Biosafety tests confirmed that qCQDs had no obvious toxic and side effects during the testing stage. The analysis of quantitative proteomics revealed that qCQDs mainly acted on ribosomal proteins in Staphylococcus aureus (Gram-positive bacteria) and significantly down-regulated proteins associated with citrate cycle in Escherichia coli (Gram-negative bacteria). Meanwhile, real-time quantitative PCR confirmed that the variation trend of genes corresponding to the proteins associated with ribosome and citrate cycle was consistent with the proteomic results after treatment of qCQDs, suggesting that qCQDs has a new antibacterial mechanism which is different from the reported carbon quantum dots with antibacterial action. STATEMENT OF SIGNIFICANCE: : With the development of the research on carbon quantum dots, the application of carbon quantum dots in the field of medicine has attracted extensive attention. In this paper, quaternized carbon quantum dots (qCQDs) with antimicrobial activity prepared by specific methods were studied, including antimicrobial spectrum, antimicrobial mechanism and in vivo antimicrobial application. The antimicrobial mechanism of qCQDs was studied by proteomics and RT-qRCR, and the different mechanisms of qCQDs against Gram-positive and Gram-negative bacteria were also found. This study provides a research foundation for the application of carbon quantum dots in antimicrobial field, and also expands the application range of carbon quantum dots in medicine field.

2.
PLoS Negl Trop Dis ; 15(10): e0009911, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34710095

RESUMO

Wolbachia are maternally transmitted intracellular bacteria that can naturally and artificially infect arthropods and nematodes. Recently, they were applied to control the spread of mosquito-borne pathogens by causing cytoplasmic incompatibility (CI) between germ cells of females and males. The ability of Wolbachia to induce CI is based on the prevalence and polymorphism of Wolbachia in natural populations of mosquitoes. In this study, we screened the natural infection level and diversity of Wolbachia in field-collected mosquitoes from 25 provinces of China based on partial sequence of Wolbachia surface protein (wsp) gene and multilocus sequence typing (MLST). Among the samples, 2489 mosquitoes were captured from 24 provinces between July and September, 2014 and the remaining 1025 mosquitoes were collected month-by-month in Yangzhou, Jiangsu province between September 2013 and August 2014. Our results showed that the presence of Wolbachia was observed in mosquitoes of Aedes albopictus (97.1%, 331/341), Armigeres subalbatus (95.8%, 481/502), Culex pipiens (87.0%, 1525/1752), Cx. tritaeniorhynchus (17.1%, 14/82), but not Anopheles sinensis (n = 88). Phylogenetic analysis indicated that high polymorphism of wsp and MLST loci was observed in Ae. albopictus mosquitoes, while no or low polymorphisms were in Ar. subalbatus and Cx. pipiens mosquitoes. A total of 12 unique mutations of deduced amino acid were identified in the wsp sequences obtained in this study, including four mutations in Wolbachia supergroup A and eight mutations in supergroup B. This study revealed the prevalence and polymorphism of Wolbachia in mosquitoes in large-scale regions of China and will provide some useful information when performing Wolbachia-based mosquito biocontrol strategies in China.

3.
Anal Chim Acta ; 1179: 338853, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34535261

RESUMO

The content of deferasirox (DEF) in plasma is significant in ß-thalassemia patient that needs long-term transfusion therapy, while the effective and simple strategy for DEF monitoring is still limited. The carbon dots (CDs) prepared from citric acid monohydrate and glutathione exhibit weakly modulated fluorescence intensity to several common metal ions containing Cu2+. Interestingly, the process of interaction of Cu2+ and DEF forms the chelation of Cu2+ and DEF (Cu-DEF) with the absorbance wavelength of DEF at 320 nm shifting to 332 nm for Cu-DEF. And the obtained Cu-DEF will effectively quench CDs through inner filter effect (IFE). Accordingly, a facile signal-off fluorescent method based on CDs as probe is developed for DEF detection using Cu2+ as medium. And the proposed method exhibits linear range of 0.5-20 µg/mL with the detection limit of 0.33 µg/mL for DEF under the optimized conditions. Moreover, the developed assay is further expanded to test the content of DEF in dispersible tablet and plasma with accuracy and reproducibility. Such cost-effective and sensitive fluorescent assay just through simple mixing operation present a valuable strategy for drug monitoring.


Assuntos
Carbono , Pontos Quânticos , Deferasirox , Corantes Fluorescentes , Humanos , Reprodutibilidade dos Testes , Espectrometria de Fluorescência
4.
CNS Neurosci Ther ; 27(12): 1531-1539, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34551193

RESUMO

AIM: The role of vascular dementia (VaD)-associated genes in Alzheimer's disease (AD) remains elusive despite similar clinical and pathological features. We aimed to explore the relationship between these genes and AD in the Chinese population. METHODS: Eight VaD-associated genes were screened by a targeted sequencing panel in a sample of 3604 individuals comprising 1192 AD patients and 2412 cognitively normal controls. Variants were categorized into common variants and rare variants according to minor allele frequency (MAF). Common variant (MAF ≥ 0.01)-based association analysis was conducted by PLINK 1.9. Rare variant (MAF < 0.01) association study and gene-based aggregation testing of rare variants were performed by PLINK 1.9 and Sequence Kernel Association Test-Optimal (SKAT-O test), respectively. Age at onset (AAO) and Mini-Mental State Examination (MMSE) association studies were performed with PLINK 1.9. Analyses were adjusted for age, gender, and APOE ε4 status. RESULTS: Four common COL4A1 variants, including rs874203, rs874204, rs16975492, and rs1373744, exhibited suggestive associations with AD. Five rare variants, NOTCH3 rs201436750, COL4A1 rs747972545, COL4A1 rs201481886, CST3 rs765692764, and CST3 rs140837441, showed nominal association with AD risk. Gene-based aggregation testing revealed that HTRA1 was nominally associated with AD. In the AAO and MMSE association studies, variants in GSN, ITM2B, and COL4A1 reached suggestive significance. CONCLUSION: Common variants in COL4A1 and rare variants in HTRA1, NOTCH3, COL4A1, and CST3 may be implicated in AD pathogenesis. Besides, GSN, ITM2B, and COL4A1 are probably involved in the development of AD endophenotypes.

5.
Infect Genet Evol ; 93: 104993, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34242774

RESUMO

Avian influenza virus (AIV) H7N9 that emerged in 2013 in eastern China is a novel zoonotic agent mainly circulating in poultry without clinical signs but causing severe disease with high fatality in humans in more than 5 waves. Since the emergence of highly pathogenic (HP) H7N9 variants in 2016, it has induced heavy losses in the poultry industry leading to the implementation of an intensive nationwide vaccination program at the end of wave 5 (September 2017). To characterize the ongoing evolution of H7N9 AIV, we conducted analyses of H7N9 glycoprotein genes obtained from 2013 to 2019. Bayesian analyses revealed a decreasing population size of HP H7N9 variants post wave 5. Phylogenetic topologies revealed that two novel small subclades were formed and carried several fixed amino acid mutations that were along HA and NA phylogenetic trees since wave 5. Some of the mutations were located at antigenic sites or receptor binding sites. The antigenic analysis may reveal a significant antigenic drift evaluated by hemagglutinin inhibition (HI) assay and the antigenicity of H7N9 AIV might evolute in large leaps in wave 7. Molecular simulations found that the mutations (V135T, S145P, and L226Q) around the HA receptor pocket increased the affinity to α2,3-linked sialic acid (SIA) while decreased to α2,6-linked SIA. Altered affinity may suggest that HP H7N9 variations aggravate the pathogenicity to poultry but lessen the threat to public health. Selection analyses showed that the HP H7N9 AIV experienced an increasing selection pressure since wave 5, and the national implementation of vaccination might intensify the role of natural selection during the evolution waves 6 and 7. In summary, our data provide important insights about the genetic and antigenic diversity of circulating HP H7N9 viruses from 2017 to 2019. Enhanced surveillance is urgently warranted to understand the current situation of HP H7N9 AIV.

6.
Sci Rep ; 11(1): 12079, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103541

RESUMO

Urban flooding can be predicted by using different modeling approaches. This study considered different methods of modeling the dynamic flow interactions between pipe systems and surface flooding in urban areas. These approaches can be divided into two categories based on surface runoff collection units. This paper introduces a new hydrodynamic model that couples the storm water management model and the 2D overland model. The model's efficiency was validated based on the aforementioned experimental dataset; agreement was verified by correlation values above 0.6. Additionally, this study used different approaches and compared their accuracy in predicting flooding patterns. The results show that the use of sub-catchments to model the collection of surface runoff was not predictive of the inundation process, indicating a lower goodness of fit with the recorded values than that of adopting cells. Moreover, to determine which method of adopting cells to collect runoff could better predict rainstorm-induced inundation, an error and correlation analysis was conducted. The analysis found low error and high correlation, suggesting that inundation can be effectively predicted by the new approaches. Ultimately, this study contributes to existing work on numerical analysis of the interaction methods of urban flooding.

7.
Mater Sci Eng C Mater Biol Appl ; 123: 111971, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33812599

RESUMO

Widespread bacterial infection and the spread of antibiotic resistance exhibit increasing threat to the public and thus require new antibacterial strategies. Carbon quantum dots (CQDs) have been extensively investigated to play fluorescent, catalytic roles and even potential biomedical functions containing sterilization. However, synthetic understanding of the interaction of CQDs and bacteria, the exhibition of antibacterial ability, and the risk of resistance evolution remain lacking. Herein, a simple one-pot method was fabricated to prepare positively charged CQDs (PC-CQDs) as a broad-spectrum antibacterial agent. PC-CQDs possessed effective antibacterial activity against all tested Gram-positive, Gram-negative, and drug-resistant bacteria. Investigation of the antibacterial mechanism of PC-CQDs indicated that small-sized PC-CQDs functionalized with -NH2 and -NH induced strong adherence behavior on the bacterial cell membrane. Moreover, the entry of PC-CQDs caused conformational changes in the genes and generation of reactive oxygen species in the bacteria. Safety evaluation illustrated that PC-CQDs did not trigger detectable drug resistance or hemolysis. Furthermore, PC-CQDs effectively promoted the antibacterial treatment of mixed Staphylococcus aureus and Escherichia coli infected wound in rats with low in vivo toxicity. These results suggested that PC-CQDs are a potential antibacterial candidate for real wound healing applications in complex bacterial infections and even resistant bacteria-caused infections.


Assuntos
Pontos Quânticos , Animais , Antibacterianos/farmacologia , Bactérias , Carbono , Ratos , Cicatrização
8.
Front Immunol ; 12: 645426, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33659011

RESUMO

Marek's disease virus (MDV) is a highly oncogenic alphaherpesvirus that causes deadly T-cell lymphomas and serves as a natural virus-induced tumor model in chickens. The most efficacious vaccine, CVI988/Rispens (CVI988), against MD has been used for several decades. However, the mechanisms leading to protective immunity following vaccination are not fully understood. In this study, employing multi-parameter flow cytometry, we performed a comprehensive analysis of T cell responses in CVI988-vaccinated chickens. CVI988 vaccination induced significant expansion of γδ T cells and CD8α+ T cells but not CD4+ T cells in spleen, lung and blood at early time-points. The expansion of these cells was CVI988-specific as infection with very virulent MDV RB1B did not elicit expansion of either γδ or CD8α+ T cells. Phenotypic analysis showed that CVI988 vaccination elicited preferential proliferation of CD8α+ γδ T cells and CD8αα co-receptor expression was upregulated on γδ T cells and CD8α+ T cells after immunization. Additionally, cell sorting and quantitative RT-PCR showed that CVI988 vaccination activated γδ T cells and CD8α+ T cells which exhibited differential expression of cytotoxic and T cell-related cytokines. Lastly, secondary immunization with CVI988 induced the expansion of CD8+ T cells but not γδ T cells at higher magnitude, compared to primary immunization, suggesting CVI988 did induce memory CD8+ T cells but not γδ T cells in chickens. Our results, for the first time, reveal a potential role of γδ T cells in CVI988-induced immune protection and provide new insights into the mechanism of immune protection against oncogenic MDV.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/farmacologia , Galinhas , Herpesvirus Galináceo 2/imunologia , Doenças das Aves Domésticas , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Vacinas Virais/farmacologia , Animais , Galinhas/imunologia , Galinhas/virologia , Doença de Marek/imunologia , Doença de Marek/prevenção & controle , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/virologia , Vacinação
9.
BMC Vet Res ; 17(1): 80, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33588843

RESUMO

BACKGROUND: Genotype S H9N2 viruses have become predominant in poultry in China since 2010. These viruses frequently donate their whole internal gene segments to other emerging influenza A subtypes such as the novel H7N9, H5N6, and H10N8 viruses. We recently reported that the PB2 and M genes of the genotype S H9N2 virus, which are derived from the G1-like virus, enhance the fitness of H5Nx and H7N9 avian influenza viruses in chickens and mice. However, whether the G1-like PB2 and M genes are preferentially incorporated into progeny virions during virus reassortment remains unclear; whether the G1-like PB2 and M genes from different subtypes are differentially incorporated into new virion progeny remains unknown. RESULTS: We conducted a reassortment experiment with the use of a H7N9 virus as the backbone and found that G1-like M/PB2 genes were preferentially incorporated in progeny virions over F/98-like M/PB2 genes. Importantly, the preference varied among G1-like M/PB2 genes of different subtypes. When competing with F/98-like M/PB2 genes during reassortment, both the M and PB2 genes from the H7N9 virus GD15 showed an advantage, whereas only the PB2 gene from the H9N2 virus CZ73 and the M gene from the H9N2 virus AH320 displayed the advantage. CONCLUSION: Our findings highlight the preferential and variable advantages of H9N2-derived G1-like M and PB2 genes in incorporating them into H7N9 progeny virions over SH14-derived F/98-like M/PB2 genes.


Assuntos
Subtipo H7N9 do Vírus da Influenza A/genética , Vírus da Influenza A Subtipo H9N2/genética , Vírus Reordenados/genética , Animais , Embrião de Galinha , Coinfecção , Cães , Genótipo , Células HEK293 , Humanos , Células Madin Darby de Rim Canino , Vírus Reordenados/crescimento & desenvolvimento , Proteínas da Matriz Viral/genética , Vírion
10.
Viruses ; 12(12)2020 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-33291218

RESUMO

Avian influenza virus (AIV) emerged and has continued to re-emerge, continuously posing great threats to animal and human health. The detection of hemagglutination inhibition (HI) or virus neutralization antibodies (NA) is essential for assessing immune protection against AIV. However, the HI/NA-independent immune protection is constantly observed in vaccines' development against H7N9 subtype AIV and other subtypes in chickens and mammals, necessitating the analysis of the cellular immune response. Here, we established a multi-parameter flow cytometry to examine the innate and adaptive cellular immune responses in chickens after intranasal infection with low pathogenicity H7N9 AIV. This assay allowed us to comprehensively define chicken macrophages, dendritic cells, and their MHC-II expression, NK cells, γδ T cells, B cells, and distinct T cell subsets in steady state and during infection. We found that NK cells and KUL01+ cells significantly increased after H7N9 infection, especially in the lung, and the KUL01+ cells upregulated MHC-II and CD11c expression. Additionally, the percentages and numbers of γδ T cells and CD8 T cells significantly increased and exhibited an activated phenotype with significant upregulation of CD25 expression in the lung but not in the spleen and blood. Furthermore, B cells showed increased in the lung but decreased in the blood and spleen in terms of the percentages or/and numbers, suggesting these cells may be recruited from the periphery after H7N9 infection. Our study firstly disclosed that H7N9 infection induced local and systemic cellular immune responses in chickens, the natural host of AIV, and that the flow cytometric assay developed in this study is useful for analyzing the cellular immune responses to AIVs and other avian infectious diseases and defining the correlates of immune protection.


Assuntos
Galinhas/imunologia , Galinhas/virologia , Imunidade Celular , Subtipo H7N9 do Vírus da Influenza A/imunologia , Influenza Aviária/imunologia , Imunidade Adaptativa , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Biomarcadores , Citometria de Fluxo , Imunidade Inata , Influenza Aviária/virologia , Linfócitos T/imunologia , Linfócitos T/metabolismo
11.
Front Chem ; 8: 591860, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195095

RESUMO

Fluoride anions play a key role in human health and chemical engineering, such as in organic synthesis and biological processes. The development of high-sensitivity naked-eye detection sensors for fluoride anions in organic solutions is crucial and challenging. In this study, (3Z,3'Z)-3,3'-[4,4,9,9-tetrakis(4-hexylphenyl)-4,9-dihydro-s-indaceno(1,2-b:5,6-b')dithiophene]-2,7-diylbis(methan-1-yl-1-ylidene) bis(6-bromo-indolin-2-one) (IDTI) was designed and used as a fluoride chemosensor for the first time. IDTI is a highly sensitive fluoride sensor with a detection limit of as low as 1 × 10-7 M. In addition, upon the reaction of IDTI with fluoride anions in a tetrahydrofuran (THF) solution, color changes from red to yellow under ambient light and from purple to green under UV light were detectable by the naked eye. These studies indicate that IDTI is a promising fluoride chemosensor.

12.
J Dairy Sci ; 103(12): 11178-11189, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33041026

RESUMO

Heat treatment is the most common method used to make milk safe; however, it leads to changes in the organoleptic and nutritional properties of milk. This study aimed to investigate the effects of different heat treatments on nutrients and microbiota of camel milk. The results showed that the nutrient composition of camel milk could be influenced by heat treatment. Ultra-high-temperature treatment of samples significantly reduced levels of camel milk proteins, vitamin C, and lactose, but did not significantly alter the amino acids content. Analysis of 16S rRNA amplicon sequences demonstrated that the composition of the intestinal microbiota of mice fed different heat-treated camel milks changed, as did the production of short-chain fatty acids as determined by gas chromatography-mass spectrometry. High temperature/short time treatment had similar effects to UHT treatment on microbial diversity of camel milk; however, the low temperature/long time treatment had different effects. In addition, higher-temperature treatments changed the abundance of key bacteria at the genus level. These results demonstrated that different heat treatments not only resulted in some nutrient loss, but also changed the proliferation of some probiotic genera. Our results could provide the basis for the potential industrial application of camel milk processing technologies.


Assuntos
Bactérias/metabolismo , Camelus , Microbioma Gastrointestinal , Temperatura Alta , Leite/química , Animais , Bactérias/classificação , Lactose/análise , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Leite/metabolismo , Nutrientes/metabolismo , Probióticos , RNA Ribossômico 16S/análise
13.
Zhongguo Zhen Jiu ; 40(7): 787-90, 2020 Jul 12.
Artigo em Chinês | MEDLINE | ID: mdl-32648406

RESUMO

In the view of the defects of the commonly used moxibustion instruments and moxa heating instruments, such as the moxa ash cannot be removed automatically, the temperature of moxibustion and moxibustion smoke is difficult to be stabilized and adjusted, and the instruments are complex and expensive, a moxibustion device with separated moxibustion smoke and heat is designed. This device can automatically remove the moxa ash and keep it on the isolation net; the temperature of the moxibustion outlet is maintained at 43-48 ℃ (effective moxibustion temperature) for more than 40 minutes, and there is no visible moxa smoke; the temperature of the moxa smoke outlet is controlled between 28-75 ℃, and the effective discharge of moxa smoke can be realized without external power equipment. This device has the advantages of stable and controllable temperature of moxibustion outlet and moxa smoke outlet, automatic removal and collection of moxa ash, separation of moxa smoke without additional power, etc., which can be used in clinical and animal experiments for moxa heating, moxa smoke removal, etc.


Assuntos
Temperatura Alta , Moxibustão/instrumentação , Fumaça , Desenho de Equipamento
14.
Colloids Surf B Biointerfaces ; 192: 111030, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32353709

RESUMO

Chondroitin sulfate (CS) plays an increasingly important role in clinical settings and pharmacy quality control. However, sensitive and simple methods for CS detection remain limited. In this work, positively charged nitrogen doped carbon dots (P-NCDs) with internal luminescence and quenching property to FAM-labeled random-sequence ssDNA (F-ssDNA) were prepared by a simple heating method. P-NCDs attached and quenched F-ssDNA through electrostatic interaction to form the system of P-NCDs and F-ssDNA (P-NCDs/F-ssDNA) with retained fluorescence intensity of P-NCDs. The highly negatively charged CS reacted electrostatically with P-NCDs and then replaced F-ssDNA in P-NCDs/F-ssDNA to recover the fluorescence intensity of the original quenched F-ssDNA while retaining the internal fluorescence intensity of P-NCDs. Thus, by using restored F-ssDNA as the signal controlled by adding CS to P-NCDs/F-ssDNA, a ratiometric fluorescence strategy based on the retained fluorescence of P-NCDs as reference signal was fabricated through synchronous fluorescence spectrometry for the sensitive detection of CS. Under the optimal experimental conditions, a linear equation for CS was obtained for CS concentration within the range of 0.05-2.0 µg/mL. The method was also successfully applied for the accurate determination of CS in joint fluid samples of arthritic patients, chondroitin sulfate tablets, and chondroitin sulfate eye drops, suggesting its appreciable application potential in the clinic.

15.
Mater Sci Eng C Mater Biol Appl ; 111: 110782, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32279744

RESUMO

Polyetheretherketone (PEEK) is an ideal implant material for orthopedic and dental application due to its high biocompatibility and mechanical property. However, biological inertness of PEEK hinders the effective clinical applications in treating bone defect, especially in the situation accompanied by bacterial infection. In this study, a layer-by-layer (LBL) deposition method with controlled cycles was developed to rapidly construct brushite (CaHPO4·2H2O) (CaP) layers containing gentamicin sulfate (GS) on PEEK to obtain CaP-and-GS modified PEEK, named as PEEK/CaP-GS. Different PEEK/CaP-GS, like PEEK/CaP-GS*3, PEEK/CaP-GS*6 and PEEK/CaP-GS*9 were conveniently prepared by repeating the LBL cycles to 3, 6 and 9 times, respectively. The morphology, structure and surface property of the fabricated PEEK/CaP-GS were carefully characterized. In vitro antibacterial experiments illustrated that all of the PEEK/CaP-GS samples had excellent and sustained antibacterial property. Cell proliferation experiments revealed the acceptable biocompatibility and cell osteogenic differentiation of PEEK/CaP-GS, especially in PEEK/CaP-GS*6. X-ray, µ-CT, and histological analysis showed that PEEK/CaP-GS exhibited in vivo antibacterial activity and osseointegration ability in the treatment of bone defect with infection. In both the in vitro and the in vivo experiments, PEEK/CaP-GS*6 prepared from the 6 LBL cycles exhibited the best antibacterial and osseointegration ability for bone healing. This work opens new avenue of the facile and effective modification of PEEK with special biological functions for clinical application, especially for the implants requiring excellent antibacterial and osseointegration ability.


Assuntos
Antibacterianos/química , Materiais Biocompatíveis/química , Fosfatos de Cálcio/química , Cetonas/química , Polietilenoglicóis/química , Animais , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Materiais Biocompatíveis/metabolismo , Materiais Biocompatíveis/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fêmur/diagnóstico por imagem , Fêmur/patologia , Humanos , Fígado/patologia , Osseointegração/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Próteses e Implantes , Ratos , Ratos Sprague-Dawley , Staphylococcus aureus/efeitos dos fármacos , Propriedades de Superfície , Microtomografia por Raio-X
16.
Cell Mol Life Sci ; 77(16): 3103-3116, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32080753

RESUMO

Marek's disease virus (MDV) is a highly oncogenic alphaherpesvirus that causes deadly T-cell lymphomas and serves as a natural virus-induced tumor model in chickens. Although Marek's disease (MD) is well controlled by current vaccines, the evolution of MDV field viruses towards increasing virulence is concerning as a better vaccine to combat very virulent plus MDV is still lacking. Our understanding of molecular and cellular immunity to MDV and its immunopathogenesis has significantly improved, but those findings about cellular immunity to MDV are largely out-of-date, hampering the development of more effective vaccines against MD. T-cell-mediated cellular immunity was thought to be of paramount importance against MDV. However, MDV also infects macrophages, B cells and T cells, leading to immunosuppression and T-cell lymphoma. Additionally, there is limited information about how uninfected immune cells respond to MDV infection or vaccination, specifically, the mechanisms by which T cells are activated and recognize MDV antigens and how the function and properties of activated T cells correlate with immune protection against MDV or MD tumor. The current review revisits the roles of each immune cell subset and its effector mechanisms in the host immune response to MDV infection or vaccination from the point of view of comparative immunology. We particularly emphasize areas of research requiring further investigation and provide useful information for rational design and development of novel MDV vaccines.


Assuntos
Galinhas/imunologia , Galinhas/virologia , Imunidade Celular/imunologia , Doença de Marek/imunologia , Vírus Oncogênicos/imunologia , Linfócitos T/imunologia , Animais , Herpesvirus Galináceo 2/imunologia , Humanos , Doença de Marek/virologia , Linfócitos T/virologia , Virulência/imunologia
17.
Anal Chim Acta ; 1103: 212-219, 2020 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-32081186

RESUMO

The expression level of miRNA-21 is closely related to the occurrence and development of cancer, especially in gastrointestinal cancer. Monitoring miRNA-21 has clinical application in the diagnosis and evaluation of gastrointestinal cancer. A turn-on ratiometric fluorescence bioassay based on the T7 exonuclease-mediated cyclic enzymatic amplification method was developed for miRNA-21 determination by using carbon dots (CDs) and FAM-labeled ssDNA as the signal source. CDs demonstrated the triple functions of built-in internal fluorescence, probe carrier, and quencher in this strategy. In the absence of miRNA-21, FAM-labeled ssDNA would be adsorbed and quenched by CDs. The addition of miRNA-21 induced cycle hydrolysis from the 5' end by the T7 exonuclease and then released the short-cleaved FAM-labeled oligonucleotides. Then, the increased FAM signal (FFAM) and the stable CD signal (FCDs) would be tested through a ratiometric routine for the quantification of miRNA-21. The FFAM/FCDs value showed a good linear relationship with the concentration of miRNA-21 in the range of 0.05-10 nM, and the detection limit for miRNA-21 was 1 pM with excellent selectivity and reproducibility. Furthermore, this sensor successfully evaluated the expression level of miRNA-21 in clinical blood samples from healthy individuals and gastrointestinal cancer patients, and the results were highly consistent with those of qRT-PCR, suggesting the great clinical application value in the diagnosis of cancer associated with miRNA-21 expression levels.


Assuntos
Técnicas Biossensoriais/métodos , Corantes Fluorescentes/química , MicroRNAs/sangue , Pontos Quânticos/química , Bacteriófago T7/enzimologia , Carbono/química , Sondas de DNA/química , Sondas de DNA/genética , DNA de Cadeia Simples/química , DNA de Cadeia Simples/genética , Exodesoxirribonucleases/química , Neoplasias Gastrointestinais/sangue , Humanos , Limite de Detecção , MicroRNAs/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Hibridização de Ácido Nucleico , Reprodutibilidade dos Testes , Espectrometria de Fluorescência
18.
Transbound Emerg Dis ; 67(2): 758-768, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31631569

RESUMO

Genotype S H9N2 avian influenza virus, which has been predominant in China since 2010, contributed its entire internal gene cassette to the genesis of novel reassortant influenza viruses, including H5Nx, H7N9 and H10N8 viruses that pose great threat to poultry and humans. A key feature of the genotype S H9N2 virus is the substitution of G1-like M and PB2 genes for the earlier F/98-like M and PB2 of genotype H virus. However, how this gene substitution has influenced viral adaptability of emerging influenza viruses in mammals remains unclear. We report here that reassortant H5Nx and H7N9 viruses with the genotype S internal gene cassette displayed enhanced replication and virulence over those with genotype H internal gene cassette in cell cultures as well as in the mouse models. We showed that the G1-like PB2 gene was associated with increased polymerase activity and improved nuclear accumulation compared with the F/98-like counterpart, while the G1-like M gene facilitated effective translocation of RNP to cytoplasm. Our findings suggest that the genotype S H9N2 internal gene cassette, which possesses G1-like M and PB2 genes, is superior to that of genotype H, in optimizing viral fitness, and thus have implications for assessing the potential risk of these gene introductions to generate emerging influenza viruses.


Assuntos
Galinhas/virologia , Vírus da Influenza A/genética , Influenza Aviária/virologia , Influenza Humana/virologia , RNA Polimerase Dependente de RNA/genética , Vírus Reordenados , Proteínas da Matriz Viral/genética , Proteínas Virais/genética , Animais , Embrião de Galinha , Cães , Feminino , Genótipo , Células HEK293 , Humanos , Subtipo H7N9 do Vírus da Influenza A/genética , Subtipo H7N9 do Vírus da Influenza A/patogenicidade , Subtipo H7N9 do Vírus da Influenza A/fisiologia , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/patogenicidade , Vírus da Influenza A Subtipo H9N2/fisiologia , Vírus da Influenza A/patogenicidade , Vírus da Influenza A/fisiologia , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos BALB C , Virulência
19.
Virol J ; 16(1): 108, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31455344

RESUMO

Bovine leukemia virus (BLV) causes enzootic bovine leucosis and is widely spread worldwide, except several European countries, Australia and New Zealand. Although BLV is highly prevalent in China, information about the genetic diversity and evolutionary dynamics of BLV among Chinese dairy herds is still lacking. To determine the genetic variability of BLV, 219 cows from four cities of Ningxia province of China were screened for BLV infection by fluorescence resonance energy transfer (FRET)-PCR and sequencing, 16 selected positive samples were subjected to molecular characterization. Phylogenetic analysis using the neighbor-joining (NJ) method on complete sequences of envelope (env) gene of BLV obtained from China and those available in GenBank (representing BLV genotypes 1-10) revealed that those Chinese strains belonged to genotypes 4 and 6. Totally, 23 mutations were identified and 16 of them were determined to be unique mutations among Chinese strains. Alignment of the deduced amino acid sequences demonstrated six mutations in glycoprotein 51 (gp51) and three mutations in glycoprotein 30 (gp30) located in the identified neutralizing domain (ND), CD8+ T cell epitope, E-epitope, B-epitope, gp51N12 and cytoplasmic domain of transmembrane protein. This study reported for the first time the BLV genotype 4 in China, and further studies are warranted to compare its immunogenicity and pathogenicity with other BLV genotypes.


Assuntos
Doenças dos Bovinos/virologia , Leucose Enzoótica Bovina/virologia , Evolução Molecular , Variação Genética , Genótipo , Vírus da Leucemia Bovina/genética , Mutação , Animais , Bovinos , China , Indústria de Laticínios , Feminino , Genes env , Vírus da Leucemia Bovina/classificação , Filogenia , Análise de Sequência de DNA , Proteínas do Envelope Viral/genética
20.
Virology ; 535: 218-226, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31325836

RESUMO

Genotype S H9N2 viruses frequently donate their internal genes to facilitate the generation of novel influenza viruses, e.g., H5N6, H7N9, and H10N8, which have caused human infection. Genotype S was originated from the replacement of F/98-like M and PB2 genes of the genotype H with those from G1-like lineage. However, whether this gene substitution will influence the viral fitness of emerging influenza viruses remains unclear. We found that H5Nx and H7N9 viruses with G1-like PB2 or M gene exhibited higher virulence and replication than those with F/98-like PB2 or M in chickens. We also determined the functional significance of G1-like PB2 in conferring increased polymerase activity and improved nucleus transportation efficiency, and facilitated RNP nuclear export by G1-like M. Our results suggest that G1-like PB2 and M genes optimize viral fitness, and thus play a crucial role in the genesis of emerging influenza viruses that cause rising prevalence in chickens.


Assuntos
Aptidão Genética , Vírus da Influenza A/crescimento & desenvolvimento , RNA Polimerase Dependente de RNA/metabolismo , Vírus Reordenados/crescimento & desenvolvimento , Proteínas da Matriz Viral/metabolismo , Proteínas Virais/metabolismo , Animais , Galinhas , Vírus da Influenza A/genética , Influenza Aviária/virologia , RNA Polimerase Dependente de RNA/genética , Vírus Reordenados/genética , Proteínas da Matriz Viral/genética , Proteínas Virais/genética , Virulência
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