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1.
Front Microbiol ; 12: 752537, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803973

RESUMO

Mycobacteria encounter a number of environmental changes during infection and respond using different mechanisms. Small RNA (sRNA) is a post-transcriptionally regulatory system for gene functions and has been investigated in many other bacteria. This study used Mycobacterium tuberculosis and Mycobacterium bovis Bacillus Calmette-Guérin (BCG) infection models and sequenced whole bacterial RNAs before and after host cell infection. A comparison of differentially expressed sRNAs using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) and target prediction was carried out. Six pathogenically relevant stress conditions, growth rate, and morphology were used to screen and identify sRNAs. From these data, a subset of sRNAs was differentially expressed in multiple infection groups and stress conditions. Many were found associated with lipid metabolism. Among them, ncBCG427 was significantly downregulated when BCG entered into macrophages and was associated with increased biofilm formation. The reduction of virulence possibility depends on regulating lipid metabolism.

2.
Injury ; 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34689988

RESUMO

OBJECTIVE: To explore the clinical characteristics and the short-term efficacy of posterior operation for traumatic lumbar spondylolisthesis. METHODS: All 28 patients (between January 2013 and June 2018) were treated with lumbar pedicle screw fixation combined with posterior intervertebral fusion. The clinical data and imaging materials of these patients were retrospectively analyzed. RESULTS: The mean follow-up period was 24.3 months (12-36 months). The average VAS score and JOA score were significantly improved after surgery, and the difference was statistically significant (P<0.05).The last follow-up X-ray showed that 16 cases were degree 0 and 12 cases were degree I according to Meyerding grading, which were statistically improved compared with preoperative. Postoperative CT indicated lumbar internal fixation well, and the lumbar fusion rate was 100%. The Frankel grading of neurological function was significantly improved compared with preoperative. CONCLUSION: Acute traumatic lumbar spondylolisthesis is caused by severe trauma and mostly occurred at L4/L5 and L5/S1 level. Early posterior reduction, decompression and intervertebral fusion can achieve satisfactory clinical and radiological outcome.

3.
PLoS One ; 16(10): e0257920, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34618810

RESUMO

Tuberculosis (TB), a contagious disease mainly caused by Mycobacterium tuberculosis (M. tb), Mycobacterium bovis (M. bovis), and Mycobacterium caprae (M. caprae), poses a major global threat to the health of humans and many species of animals. Developing an ante-mortem detection technique for different species would be of significance in improving the surveillance employing a One Health strategy. To achieve this goal, a universal indirect ELISA was established for serologically detecting Mycobacterium tuberculosis complex infection for multiple live hosts by using a fusion protein of MPB70, MPB83, ESAT6, and CFP10 common in M. tb, M. bovis, and M. caprae as the coating antigen (MMEC) and HRP-labeled fusion protein A and G as a secondary antibody. After testing the known positive and negative sera, the receiver operating characteristic curves were constructed to decide the cut-off values. Then, the diagnostic sensitivity and specificity of MMEC/AG-iELISA were determined as 100.00% (95% CI: 96.90%, 100.00%) and 100.00% (95% CI: 98.44%, 100.00%) for M. bovis infection of cattle, 100.00% (95% CI: 95.00%, 100.00%) and 100.0% (95% CI: 96.80%, 100.00%) for M. bovis infection of sheep, 90.74% (95% CI: 80.09%, 95.98%) and 98.63% (95% CI: 95.14%, 99.76%) for M. bovis infection of cervids, 100.00% (95% CI: 15.81%, 100.00%) and 98.81% (95% CI: 93.54%, 99.97%) for M. bovis infection of monkeys, 100.00% (95% CI: 86.82%, 100.00%) and 94.85% (95% CI: 91.22%, 97.03%) for M. tb infection of humans. Furthermore, this MMEC/AG-iELISA likely detects M. caprae infection in roe deer. Thus this method has a promising application in serological TB surveillance for multiple animal species thereby providing evidence for taking further action in TB control.


Assuntos
Ensaio de Imunoadsorção Enzimática , Mycobacterium tuberculosis/isolamento & purificação , Testes Sorológicos , Tuberculose/diagnóstico , Animais , Animais Selvagens/microbiologia , Anticorpos Antibacterianos/química , Anticorpos Antibacterianos/imunologia , Bovinos , Cervos/microbiologia , Testes Diagnósticos de Rotina , Humanos , Mycobacterium bovis/isolamento & purificação , Mycobacterium bovis/patogenicidade , Mycobacterium tuberculosis/genética , Ovinos/microbiologia , Tuberculose/microbiologia
4.
Front Pharmacol ; 12: 628950, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34497508

RESUMO

Diabetic nephropathy (DN) is a common diabetes associated complication. Thus, it is important to understand the pathological mechanism of DN and find the appropriate therapeutic strategy for it. Dl-3-n-Butylphthalide (DL-NBP) has anti-inflammatory and antioxidant effects, and been widely used for the treatment of stroke and cardiovascular diseases. In this study, we selected three different doses (20, 60, and 120 mg⋅kg-1 d-1) of DL-NBP and attempted to elucidate its role and molecular mechanism underlying DN. We found that DL-NBP, especially at the dose of 60 or 120 mg⋅kg-1 d-1, could significantly ameliorate diabetes-induced elevated blood urea nitrogen (BUN) and creatinine level, and alleviate renal fibrosis. Additionally, the elevated expressions of collagen and α-smooth muscle actin (α-SMA) in the kidney from db/db mice were found to be significantly suppressed after DL-NBP treatment. Furthermore, mechanistic studies revealed that DL-NBP inhibits pro-inflammatory cytokine levels, thereby ameliorating the development of renal fibrosis. Moreover, we found that DL-NBP could not only reduce the endoplasmic reticulum stress (ERS), but also suppress activation of the renin-angiotensin system to inhibit vascular endothelial growth factor (VEGF) level, which subsequently reduces the podocyte apoptosis in kidney of db/db mice. In a word, our findings suggest that DL-NBP may be a potential therapeutic drug in the treatment of DN.

5.
Lab Invest ; 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521991

RESUMO

Bioactive glass (BG) has recently shown great promise in soft tissue repair, especially in wound healing; however, the underlying mechanism remains unclear. Pyroptosis is a novel type of programmed cell death that is involved in various traumatic injury diseases. Here, we hypothesized that BG may promote wound healing through suppression of pyroptosis. To test this scenario, we investigated the possible effect of BG on pyroptosis in wound healing both in vivo and in vitro. This study showed that BG can accelerate wound closure, granulation formation, collagen deposition, and angiogenesis. Moreover, western blot analysis and immunofluorescence staining revealed that BG inhibited the expression of pyroptosis-related proteins in vivo and in vitro. In addition, while BG regulated the expression of connexin43 (Cx43), it inhibited reactive oxygen species (ROS) production. Cx43 activation and inhibition experiments further indicate that BG inhibited pyroptosis in endothelial cells by decreasing Cx43 expression and ROS levels. Taken together, these studies suggest that BG promotes wound healing by inhibiting pyroptosis via Cx43/ROS signaling pathway.

6.
mBio ; 12(5): e0101321, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34517752

RESUMO

Phage P1 is a temperate phage which makes the lytic or lysogenic decision upon infecting bacteria. During the lytic cycle, progeny phages are produced and the cell lyses, and in the lysogenic cycle, P1 DNA exists as a low-copy-number plasmid and replicates autonomously. Previous studies at the bulk level showed that P1 lysogenization was independent of multiplicity of infection (MOI; the number of phages infecting a cell), whereas lysogenization probability of the paradigmatic phage λ increases with MOI. However, the mechanism underlying the P1 behavior is unclear. In this work, using a fluorescent reporter system, we demonstrated this P1 MOI-independent lysogenic response at the single-cell level. We further observed that the activity of the major repressor of lytic functions (C1) is a determining factor for the final cell fate. Specifically, the repression activity of P1, which arises from a combination of C1, the anti-repressor Coi, and the corepressor Lxc, remains constant for different MOI, which results in the MOI-independent lysogenic response. Additionally, by increasing the distance between phages that infect a single cell, we were able to engineer a λ-like, MOI-dependent lysogenization upon P1 infection. This suggests that the large separation of coinfecting phages attenuates the effective communication between them, allowing them to make decisions independently of each other. Our work establishes a highly quantitative framework to describe P1 lysogeny establishment. This system plays an important role in disseminating antibiotic resistance by P1-like plasmids and provides an alternative to the lifestyle of phage λ. IMPORTANCE Phage P1 has been shown potentially to play an important role in disseminating antibiotic resistance among bacteria during lysogenization, as evidenced by the prevalence of P1 phage-like elements in animal and human pathogens. In contrast to phage λ, a cell fate decision-making paradigm, P1 lysogenization was shown to be independent of MOI. In this work, we built a simple genetic model to elucidate this MOI independency based on the gene-regulatory circuitry of P1. We also proposed that the effective communication between coinfecting phages contributes to the lysis-lysogeny decision-making of P1 and highlighted the significance of spatial organization in the process of cell fate determination in a single-cell environment. Finally, our work provides new insights into different strategies acquired by viruses to interact with their bacterial hosts in different scenarios for their optimal survival.

7.
Prev Vet Med ; 196: 105477, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34482152

RESUMO

Abattoir surveillance is an integral component of a bovine tuberculosis (bTB) eradication programme. The objective of this study was to determine the prevalence of bTB among culled adult dairy cows in Wuhan, China and to further assess two diagnostic procedures as an adjunct to the confirmation of M. bovis in animals with TB-like lesions. The study was conducted in an abattoir located in Wuhan, China over a period of 41 days from June to July 2019. A total of 171 culled adult dairy cows were sampled and inspected, and blood samples collected from 134 of these. The viscera and lymph nodes of the carcasses were visually inspected and palpated for TB-like lesions. A total of 28.1 % (48/171) of the carcasses had gross TB-like lesions. 89.6 % (43/48) of the animals with TB-like lesions were positive to a PCR procedure for bTB. The sensitivity and specificity for post-mortem examination for TB-like lesions using a Bayesian latent class analysis model was estimated to be 60.8 % and 86.6 %, respectively. A seroprevalence of 20.9 % (28/134) was recorded for antibody response to M. bovis antigens MPB70 and MPB83 based on an ELISA procedure. There was a low-moderate agreement between the ELISA and PCR results in the detection of bTB (Kappa = 0.46, 95 % CI: 0.24-0.67). The study confirms a high prevalence of bTB among culled adult dairy cows in the abattoir and highlights the need to implement surveillance for bTB based on post-mortem examination and ELISA and PCR methods in association with backward tracing of infected dairy herds.


Assuntos
Mycobacterium bovis , Tuberculose Bovina , Matadouros , Abate de Animais , Animais , Teorema de Bayes , Bovinos , China/epidemiologia , Indústria de Laticínios , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Reação em Cadeia da Polimerase/veterinária , Prevalência , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Tuberculose Bovina/epidemiologia
8.
Pathogens ; 10(7)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209358

RESUMO

(1) Background: Tuberculosis (TB) in humans is a serious chronic epidemic disease caused by Mycobacterium tuberculosis (M. tb). The diagnosis of TB, especially extra-pulmonary TB (EPTB), is difficult. Isolation of M. tb from culture has a low sensitivity in patients with TB and an even lower sensitivity in cases of EPTB. Although Xpert MTB/RIF assays and serological tests are more sensitive than the above tests, they still lack sensitivity for EPTB diagnosis. (2) Methods: To improve the accuracy of TB diagnosis, a Rv0222-Rv2657c-Rv1509 fusion protein based iELISA was constructed, the diagnosis of TB, pulmonary TB (PTB) and EPTB was then evaluated. Sera of 40 TB patients including 14 with PTB, 14 with EPTB and 12 with no information about the form of TB, and five pneumonia patients were investigated. (3) Results: The sensitivity of the ELISA in TB, PTB and EPTB patients was 80% (95% CI: 64.4, 90.9%), 85.7% (95% CI: 57.2, 98.2%) and 92.8% (95% CI: 66.1, 99.8%), respectively, with a specificity of 70% (95% CI: 53.5, 83.4%). Both the sensitivity and specificity with this fusion protein were higher than for CFP10/ESAT6 (used as reference antigen) fusion protein (71.4%; 95% CI: 41.9, 91.6%, and 67.5%; 95% CI: 50.9, 81.4%), respectively, in cases of EPTB. All pneumonia patients' sera tested negative in both ELISAs. (4) Conclusion: use of these new fusion proteins as antigens in serological assays has the potential to improve the diagnosis of all forms of TB in humans, especially EPTB.

9.
Water Res ; 200: 117202, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34015576

RESUMO

Warm lime softening is commonly used to reduce hardness, silica, and a small fraction of organic matter from steam-assisted gravity drainage (SAGD) produced water through the addition of lime, soda ash, MgO, coagulant and flocculant. We report a systematic study on the impact of solution chemistry on the epichlorohydrin-dimethylamine coagulant demand for the treatment of synthetic SAGD produced water. Concentrations of magnesium, calcium, sodium bicarbonate, clay (mimicking suspended solids), sodium metasilicate (representing silica), and humic acid (mimicking dissolved organic matter) were varied to study their impact on coagulant demand. The impact of the concentration of lime, soda ash, and MgO on coagulant demand was also studied. Within the studied concentration range, the coagulant dose increased linearly with increasing concentration of humic acid (Ycoagulant = 29 + 0.703XHA) and silica (Ycoagulant = 52 + 0.537Xsilica), and increased slightly with increasing concentration of lime and soda ash, but remained almost unchanged with increasing concentration of dissolved hardness, clay, or MgO. The observations were correlated to the understanding of the electrokinetic properties of CaCO3 and Mg(OH)2 particles in lime softening. The findings provide insights for evaluating onsite coagulant dose and optimizing the process.


Assuntos
Abrandamento da Água , Água , Compostos de Cálcio , Óxidos , Polímeros , Vapor
10.
Oxid Med Cell Longev ; 2020: 8586314, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33354279

RESUMO

There is a high incidence of acute and chronic skin defects caused by various reasons in clinically practice. The repair and functional reconstruction of skin defects have become a major clinical problem, which needs to be solved urgently. Previous studies have shown that fibroblast growth factor 10 (FGF10) plays a functional role in promoting the proliferation, migration, and differentiation of epithelial cells. However, little is known about the effect of FGF10 on the recovery process after skin damage. In this study, we found that the expression of endogenous FGF10 was increased during wound healing. We prepared FGF10-loaded poly(lactic-co-glycolic acid) (FGF10-PLGA) microspheres, and it could sustain release of FGF10 both in vitro and in vivo, accelerating wound healing. Further analysis revealed that compared with FGF10 alone, FGF10-PLGA microspheres significantly improved granulation formation, collagen synthesis, cell proliferation, and blood vessel density. In the meantime, we found that FGF10-PLGA microspheres inhibited the expression of endoplasmic reticulum (ER) stress markers. Notably, activating ER stress with tunicamycin (TM) reduced therapeutic effects of FGF10-PLGA microspheres in wound healing, whereas inhibition of ER stress with 4-phenyl butyric acid (4-PBA) improved the function of FGF10-PLGA microspheres. Taken together, this study indicates that FGF10-PLGA microspheres accelerate wound healing presumably through modulating ER stress.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fator 10 de Crescimento de Fibroblastos/farmacologia , Microesferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/farmacologia , Cicatrização/efeitos dos fármacos , Ferimentos e Lesões , Administração Tópica , Animais , Masculino , Camundongos , Camundongos Endogâmicos ICR , Ferimentos e Lesões/tratamento farmacológico , Ferimentos e Lesões/metabolismo , Ferimentos e Lesões/patologia
11.
Water Res ; 186: 116415, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32927423

RESUMO

Significant effort has been made to measure and understand the surface charge of CaCO3 and Mg(OH)2 particles. Many laboratory experiments have been reported on zeta potential of natural and prepared CaCO3 and a few have also been published for Mg(OH)2, however, there are very few reported measurements of zeta potential of CaCO3 and Mg(OH)2 particles at conditions relevant to lime softening, despite lime softening being a common and established process for water treatment. The present study aims to understand the interactions and electrokinetic properties of these two particles in lime softening. Effects of various experimental parameters such as pH, temperature, aging, inorganic carbon (CO32-/HCO3-), and divalent cations (Ca2+/Mg2+) on the electrokinetic properties (i.e. zeta potential) of CaCO3 and Mg(OH)2 particles were individually studied. The interactions between humic acid (mimicking natural organic matter), silicate (representing silica), clay (mimicking suspended solids) and CaCO3/Mg(OH)2 particles were studied, as well as the interactions between CaCO3 and Mg(OH)2. Thermodynamic modeling was used to predict precipitates as a function of solution chemistry and assist with data interpretation. The results provide considerable insight into factors that are of importance to lime softening.


Assuntos
Hidróxido de Magnésio , Purificação da Água , Carbonato de Cálcio , Abrandamento da Água
12.
J Biosci Bioeng ; 130(6): 588-595, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32798135

RESUMO

The non-conventional yeast Pichia kudriavzevii is considered to be a promising biotechnological host for the production of organic acids under low-pH conditions. However, little is known about the low-pH stress response in P. kudriavzevii, which significantly restricts its future development. In this study, P. kudriavzevii N-X showed great tolerance to low-pH stress, but the cell aggregation upon extremely acidic conditions might be unfavorable for low-pH fermentation. We therefore conducted RNA-Seq to compare global gene expression of P. kudriavzevii N-X in response to different pH stresses. Totally 434 genes were identified to be differentially expressed genes (DEGs), and annotation and enrichment analysis suggested that multiple genes associated with regulation of membrane lipid composition, filamentous growth and arginine metabolism were differentially expressed. The increased specific activity of arginase and intracellular ammonia concentration of P. kudriavzevii cultured at pH 2.0 further implied potential roles of arginine in response to extreme low-pH conditions. Extracellular supplementation of 5 mM arginine resulted in increased pHi and cell growth at pH 2.0, meanwhile the cell aggregation was partially suppressed. Additionally, overexpression of ARG J involving in arginine synthesis can also enhance the cell growth and reduce the aggregation effect. These results suggested that increasing arginine flux might be an alternative approach in the developing of P. kudriavzevii as a platform host for production of organic acids under low-pH conditions.


Assuntos
Arginina/metabolismo , Estresse Oxidativo/genética , Pichia/genética , Pichia/metabolismo , Transcrição Genética , Fermentação , Concentração de Íons de Hidrogênio
13.
Vet Microbiol ; 242: 108564, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32122616

RESUMO

Long noncoding RNAs (lncRNAs) play important roles in the antiviral responses. However, little is known about the identification and functions of swine lncRNAs in response to pseudorabies virus type II (PRV-II). Here, we detected the expression profiles of host lncRNAs from a wild-type (PRV-II DX) and gE/TK deficient (gE-TK-PRV) PRV-II infected cells. RNA-seq identified 664 differentially expressed (DE) lncRNAs from PRV-DX infected cells, 654 DE lncRNAs from gE-TK-PRV infected cells and 276 DE lncRNAs between PRV-DX and gE-TK-PRV infected cells. The potential functions of the significant differentially expressed (SDE) lncRNAs were involved in interleukin secretion, axon extension and metabolic process based on the gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Moreover, the expression patterns of sixteen SDE lncRNAs determined by RT-qPCR exhibited high correlation (r > 0.95) with those by RNA-seq results. Western blotting assay displayed the lncA02830 did not code for protein, and the silencing of lncA02830 could significantly up-regulate the transcription levels of IRF3, IFNß as well as MX1 and inhibit the replication of PRV-II. Taken together, these data highlighted the potentials of lncRNA as targets for antiviral therapy and provided some novel knowledge of the mechanisms underlying the host interaction with PRV-II.


Assuntos
Herpesvirus Suídeo 1/genética , Interações entre Hospedeiro e Microrganismos , RNA Longo não Codificante/genética , Replicação Viral , Animais , Células Cultivadas , Herpesvirus Suídeo 1/fisiologia , Sequenciamento de Nucleotídeos em Larga Escala , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/imunologia , Imunidade Inata , Pseudorraiva/virologia , Suínos , Regulação para Cima , Proteínas do Envelope Viral/genética
14.
Adv Sci (Weinh) ; 7(2): 1902162, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31993290

RESUMO

Smart structures with manipulatable properties are highly demanded in many fields. However, there is a critical challenge in the pursuit of transparent windows that allow optical waves (wavelength of µm-nm) for transmitting while blocking microwave (wavelength of cm) in terms of absorbing electromagnetic energy, specifically for meeting the frequency requirement for the 5th generation (5G) mobile networks. For fundamentally establishing novel manipulatable microwave absorbing structures, here, new polymeric aqueous gels as both optically transparent materials and microwave absorbing materials are demonstrated, in which polar networks play significant roles in attenuating electromagnetic energy. By manipulating the hydrogen bonding networks, the resulting optically transparent solid-state gels are able to offer the capabilities for absorbing microwaves. Interestingly, such gels can be switched into an optically opaque state via converting the amorphous state into a polycrystal state when the temperature is decreased. Such ionic conductive gels can endow the assembled sandwich windows with effective microwave absorbing capability in the range of 15-40 GHz, covering a branch of 5G frequency bands. The results highlight a new strategy for using ionic conductive gels to design and fabricate manipulatable microwave stealth structures for various applications.

15.
Virology ; 542: 1-7, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31957661

RESUMO

To begin its infection, a bacteriophage first needs to adsorb to cells. The adsorption site on the cell surface may influence viral DNA injection, gene expression and cell-fate development. Here, we study the early steps of the infection cycle of coliphage P1, focusing on their correlation with spatial locations at the single-cell level. By fluorescently labeling P1 virions, we found that P1 shows no spatial preference on cell surface adsorption. In addition, live-cell phage DNA imaging revealed that adsorption sites do not affect the success rate for P1 in injecting its DNA into the cell. Furthermore, the lysis-lysogeny decision of P1 does not depend on the adsorption site, based on fluorescence reporters for the lytic and lysogenic pathways. These findings highlight the different infection strategies used by the two paradigmatic coliphages differ from those found in the paradigmatic phage lambda, highlighting that different infection strategies are used by phages.


Assuntos
Bacteriófago P1/patogenicidade , Escherichia coli/virologia , Adsorção , Bacteriófago P1/genética , Bacteriófago P1/fisiologia , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/fisiologia , Membrana Celular/virologia , Citoplasma/virologia , DNA Viral/genética , DNA Viral/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Lisogenia , Microscopia de Fluorescência , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Análise de Célula Única , Ligação Viral
16.
J Virol ; 93(20)2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31341057

RESUMO

A relatively stable and flexible capsid is critical to the viral life cycle. However, the capsid dynamics and cytosol trafficking of porcine circovirus type 2 (PCV2) during its infectious cycle are poorly understood. Here, we report the structural stability and conformation flexibility of PCV2 virions by genome labeling and the use of three monoclonal antibodies (MAbs) against the native capsid of PCV2. Genome labeling showed that the infectivity of the PCV2 virion was not affected by conjugation with deoxy-5-ethynylcytidine (EdC). Heat stability experiments indicated that PCV2 capsids started to disassemble at 65°C, causing binding incompetence for all antibodies, and the viral genome was released without capsid disassembly upon heating at 60°C. Antibody binding experiments with PCV2 showed that residues 186 to 192 were concealed in the early endosomes of epithelial PK-15 and monocytic 3D4/31 cells with or without chloroquine treatment and then exposed in PK-15 cytosol and the 3D4/31 nucleus. Viral propagation and localization experiments showed that PCV2 replication and cytosol trafficking were not significantly affected by microtubule depolymerization in monocytic 3D4/31 cells treated with nocodazole. These findings demonstrated that nuclear targeting of viral capsids involved conformational changes, the PCV2 genome was released from the assembled capsid, and the transit of PCV2 particles was independent of microtubules in 3D4/31 cells.IMPORTANCE Circovirus is the smallest virus known to replicate autonomously. Knowledge of viral genome release may provide understanding of viral replication and a method to artificially inactivate viral particles. Currently, little is known about the release model of porcine circovirus type 2 (PCV2). Here, we report the release of the PCV2 genome from assembled capsid and the intracellular trafficking of infectious PCV2 by alterations in the capsid conformation. Knowledge of PCV2 capsid stability and dynamics is essential to understanding its infectious cycle and lays the foundation for discovering powerful targets for therapeutic and prophylactic intervention.


Assuntos
Infecções por Circoviridae/virologia , Circovirus/fisiologia , Montagem de Vírus , Internalização do Vírus , Capsídeo/química , Capsídeo/metabolismo , Proteínas do Capsídeo/química , Proteínas do Capsídeo/metabolismo , Células Cultivadas , Endossomos , Genoma Viral , Interações Hospedeiro-Patógeno , Microtúbulos/metabolismo , Conformação Proteica , Relação Estrutura-Atividade
17.
Microbiol Resour Announc ; 8(17)2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31023797

RESUMO

Multiple antimicrobial-resistant strains of Salmonella enterica serovar Newport have been recorded. Study on phages infecting S. Newport may provide new therapeutics or diagnostics for this pathogen. Here, we describe the complete genome sequence of the T4-like phage Melville that uses S. Newport as one of its hosts.

18.
FEBS Open Bio ; 8(12): 1943-1952, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30524945

RESUMO

The novel zinc finger protein 121 (ZNF121) has been demonstrated to physically and functionally associate with the MYC oncoprotein to regulate cell proliferation and likely breast cancer development. To further understand how ZNF121 functions in cell proliferation and carcinogenesis, we identified and characterized the interaction of ZNF121 with zinc finger and BRCA1-interacting protein with a KRAB domain 1 (ZBRK1), a breast and ovarian cancer susceptibility protein 1 (BRCA1)-interacting protein, using the yeast two-hybrid assay and other approaches. We also found that ZNF121 bound to BRCA1. Functionally, ZFN121 suppressed the expression of ANG1 and HMGA2, two common downstream targets of ZBRK1 and BRCA1. Interestingly, ZNF121 also regulated the expression of BRCA1 and ZBRK1. These findings suggest that ZNF121 is likely a member of the BRCA1/CtIP/ZBRK1 repressor complex that plays a role in breast cancer.

19.
ACS Appl Mater Interfaces ; 10(47): 40815-40823, 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30384586

RESUMO

Smart materials and structures with tunable electromagnetic (EM) properties are highly demanded for active environmental sensitive systems. As polar molecules in the environment, in this work, water and ice are utilized as wetting and freezing conditions to manipulate the electromagnetic response behaviors in a graphene-based composite material, aiming to achieve a smart weather-manipulated EM metamaterial. Owing to the introduced polar water and ice phase in the self-assembled porous electromagnetic attenuating networks, energy consumption of EM waves is significantly altered via multiple scattering of polar induced interfaces. In frozen conditions, a wide absorption band (2-18 GHz) with efficient absorption (reflection loss < -10 dB) has been obtained. Additionally, the mechanical feature of the as-assembled metamaterials could also be manipulated via altering the weather conditions in terms of changing the phase of the introduced water. Interestingly, the mechanical properties could be massively changed while the broadband absorption capability has rarely been impacted. Implication of the results highlights an efficient method for fabricating smart EM metamaterials that are capable of being manipulated by the environment.

20.
J Chromatogr Sci ; 55(3): 284-290, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-27884874

RESUMO

Mogrol, the aglycone of mogrosides, is a potential pharmacologically active ingredient isolated from the fruits of Siraitia grosvenorii. The aim of this study was to develop and validate an LC-MS-MS method for the quantification of mogrol in rat plasma. Protein precipitation extraction procedure using methanol/water (1:1, v/v) was employed to extract mogrol from rat plasma. Chromatographic separation was performed on a reverse-phase Agilent Zorbax XDB C18 column (50 mm × 2.1 mm, 3.5 µm) with gradient elution using a mobile phase containing methanol and water, both of which contained 0.1% formic acid at a flow rate of 0.50 mL/min. The analyte was monitored by tandem-mass spectrometry with positive electrospray ionization mode. The precursor/product transitions (m/z) in the positive ion mode were 459.3→423.3 and 386.2→122.3 for mogrol and internal standard, respectively. The method was validated over the concentration range of 10.0-10,000 ng/mL with a lower limit of quantification of 10.0 ng/mL in rat plasma. Validation experiments included tests for specificity, precision, accuracy, matrix effect, and stability under different storage and handling conditions. This method was successfully utilized to pharmacokinetic evaluation of mogrol after intravenous and oral administration of a single dose in rats at 2.0 and 5.0 mg/kg, respectively. The oral absolute bioavailability (F) of mogrol was estimated to be 10.3 ± 2.15% with an elimination half-life (t1/2) value of 2.41 ± 0.11 h.


Assuntos
Cromatografia de Fase Reversa/métodos , Cucurbitaceae/química , Espectrometria de Massas em Tandem/métodos , Triterpenos/sangue , Administração Intravenosa , Administração Oral , Animais , Disponibilidade Biológica , Modelos Lineares , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Triterpenos/química , Triterpenos/farmacocinética
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