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1.
PLoS Pathog ; 20(1): e1011967, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38271479

RESUMO

Given the serious neurological complications and deaths associated with enterovirus 71 (EV71) infection, there is an urgent need to develop effective antivirals against this viral infection. In this study, we demonstrated that two Cathelicidin-derived peptides, LL-18 and FF-18 were more potent against EV71 infection than the parent peptide LL-37, which is the mature and processed form of Cathelicidin. These peptides could directly bind to the EV71 virus particles, but not to coxsackievirus, indicative of their high specificity. The binding of peptides with the virus surface occupied the viral canyon region in a way that could block virus-receptor interactions and inhibit viral uncoating. In addition, these peptide analogues could also relieve the deleterious effect of EV71 infection in vivo. Therefore, Cathelicidin-derived peptides might be excellent candidates for further development of antivirals to treat EV71 infection.


Assuntos
Enterovirus Humano A , Infecções por Enterovirus , Enterovirus , Humanos , Catelicidinas/farmacologia , Internalização do Vírus , Antivirais/metabolismo
2.
J Virol ; 98(2): e0174923, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38189249

RESUMO

Enterovirus 71 (EV71) is one of the major pathogens causing hand, foot, and mouth disease in children under 5 years old, which can result in severe neurological complications and even death. Due to limited treatments for EV71 infection, the identification of novel host factors and elucidation of mechanisms involved will help to counter this viral infection. N-terminal acetyltransferase 6 (NAT6) was identified as an essential host factor for EV71 infection with genome-wide CRISPR/Cas9 screening. NAT6 facilitates EV71 viral replication depending on its acetyltransferase activity but has little effect on viral release. In addition, NAT6 is also required for Echovirus 7 and coxsackievirus B5 infection, suggesting it might be a pan-enterovirus host factor. We further demonstrated that NAT6 is required for Golgi integrity and viral replication organelle (RO) biogenesis. NAT6 knockout significantly inhibited phosphatidylinositol 4-kinase IIIß (PI4KB) expression and PI4P production, both of which are key host factors for enterovirus infection and RO biogenesis. Further mechanism studies confirmed that NAT6 formed a complex with its substrate actin and one of the PI4KB recruiters-acyl-coenzyme A binding domain containing 3 (ACBD3). Through modulating actin dynamics, NAT6 maintained the integrity of the Golgi and the stability of ACBD3, thereby enhancing EV71 infection. Collectively, these results uncovered a novel mechanism of N-acetyltransferase supporting EV71 infection.IMPORTANCEEnterovirus 71 (EV71) is an important pathogen for children under the age of five, and currently, no effective treatment is available. Elucidating the mechanism of novel host factors supporting viral infection will reveal potential antiviral targets and aid antiviral development. Here, we demonstrated that a novel N-acetyltransferase, NAT6, is an essential host factor for EV71 replication. NAT6 could promote viral replication organelle (RO) formation to enhance viral replication. The formation of enterovirus ROs requires numerous host factors, including acyl-coenzyme A binding domain containing 3 (ACBD3) and phosphatidylinositol 4-kinase IIIß (PI4KB). NAT6 could stabilize the PI4KB recruiter, ACBD3, by inhibiting the autophagy degradation pathway. This study provides a fresh insight into the relationship between N-acetyltransferase and viral infection.


Assuntos
Enterovirus Humano A , Infecções por Enterovirus , Acetiltransferases N-Terminal , Fosfotransferases (Aceptor do Grupo Álcool) , Criança , Pré-Escolar , Humanos , 1-Fosfatidilinositol 4-Quinase/metabolismo , Actinas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antivirais , Coenzima A/metabolismo , Infecções por Coxsackievirus , Enterovirus Humano A/fisiologia , Infecções por Enterovirus/metabolismo , Infecções por Enterovirus/virologia , Proteínas de Membrana/metabolismo , Acetiltransferases N-Terminal/metabolismo , Biogênese de Organelas , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Replicação Viral/fisiologia
3.
J Virol ; 97(8): e0080223, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37504573

RESUMO

The human astrovirus (HAstV) is a non-enveloped, single-stranded RNA virus that is a common cause of gastroenteritis. Most non-enveloped viruses use membrane disruption to deliver the viral genome into a host cell after virus uptake. The virus-host factors that allow for HAstV cell entry are currently unknown but thought to be associated with the host-protease-mediated viral maturation. Using in vitro liposome disruption analysis, we identified a trypsin-dependent lipid disruption activity in the capsid protein of HAstV serotype 8. This function was further localized to the P1 domain of the viral capsid core, which was both necessary and sufficient for membrane disruption. Site-directed mutagenesis identified a cluster of four trypsin cleavage sites necessary to retain the lipid disruption activity, which is likely attributed to a short stretch of sequence ending at arginine 313 based on mass spectrometry of liposome-associated peptides. The membrane disruption activity was conserved across several other HAstVs, including the emerging VA2 strain, and effective against a wide range of lipid identities. This work provides key functional insight into the protease maturation process essential to HAstV infectivity and presents a method to investigate membrane penetration by non-enveloped viruses in vitro. IMPORTANCE Human astroviruses (HAstVs) are an understudied family of viruses that cause mild gastroenteritis but have recent cases associated with a more severe neural pathogenesis. Many important elements of the HAstV life cycle are not well understood, and further elucidating them can help understand the various forms of HAstV pathogenesis. In this study, we utilized an in vitro liposome-based assay to describe and characterize a previously unreported lipid disruption activity. This activity is dependent on the protease cleavage of key sites in HAstV capsid core and can be controlled by site-directed mutagenesis. Our group observed this activity in multiple strains of HAstV and in multiple lipid conditions, indicating this may be a conserved activity across the AstV family. The discovery of this function provides insight into HAstV cellular entry, pathogenesis, and a possible target for future therapeutics.


Assuntos
Infecções por Astroviridae , Gastroenterite , Mamastrovirus , Humanos , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/química , Mamastrovirus/genética , Tripsina , Lipossomos , Peptídeos/genética , Lipídeos , Filogenia
4.
Clin Sci (Lond) ; 138(1): 23-42, 2024 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-38060817

RESUMO

Reductions in Na+-K+-ATPase (NKA) activity and expression are often observed in the progress of various reason-induced heart failure (HF). However, NKA α1 mutation or knockdown cannot cause spontaneous heart disease. Whether the abnormal NKA α1 directly contributes to HF pathogenesis remains unknown. Here, we challenge NKA α1+/- mice with isoproterenol to evaluate the role of NKA α1 haploinsufficiency in isoproterenol (ISO)-induced cardiac dysfunction. Genetic knockdown of NKA α1 accelerated ISO-induced cardiac cell hypertrophy, heart fibrosis, and dysfunction. Further studies revealed decreased Krebs cycle, fatty acid oxidation, and mitochondrial OXPHOS in the hearts of NKA α1+/- mice challenged with ISO. In ISO-treated conditions, inhibition of NKA elevated cytosolic Na+, further reduced mitochondrial Ca2+ via mNCE, and then finally down-regulated cardiac cell energy metabolism. In addition, a supplement of DRm217 alleviated ISO-induced heart dysfunction, mitigated cardiac remodeling, and improved cytosolic Na+ and Ca2+ elevation and mitochondrial Ca2+ depression in the NKA α1+/- mouse model. The findings suggest that targeting NKA and mitochondria Ca2+ could be a promising strategy in the treatment of heart disease.


Assuntos
Insuficiência Cardíaca , Miócitos Cardíacos , Camundongos , Animais , Isoproterenol/metabolismo , Isoproterenol/farmacologia , Miócitos Cardíacos/metabolismo , Cálcio/metabolismo , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Cardiomegalia/induzido quimicamente , Cardiomegalia/genética , Cardiomegalia/metabolismo , Adenosina Trifosfatases/metabolismo
5.
Nano Lett ; 23(19): 9096-9104, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37748028

RESUMO

Vertical-cavity surface-emitting lasers (VCSELs) represent an attractive light source to integrate with OAM structures to realize chip-scale vortex lasers. Although pioneering endeavors of VCSEL-based vortex lasers have been reported, they cannot achieve large topological charges (less than l = 5) due to the insufficient space-bandwidth product (SBP) caused by the inherent limited device size. Here, by integrating a nanoprinted OAM phase structure on the VCSELs, we demonstrate a vortex microlaser with a low threshold and simple structure. A monolithic microlaser array with addressable control of vortex beams with different topological charges (l = 1 to l = 5) was achieved. Nanoprinting offers high degrees of freedom for the manipulation of spatial structures. To address the challenge of insufficient SBP, two-layer cascaded spiral phase plates were designed. Thereby, a vortex beam with l = 15 and mode purity of 83.7% was obtained. Our work paves the way for future chip-scale OAM-based information multiplexing with more channels.

6.
J Virol ; 96(6): e0011922, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35170979

RESUMO

Enterovirus 71 (EV71) is deemed a reemergent pathogen, with recent outbreaks worldwide. EV71 infection causes hand, foot, and mouth disease (HFMD) and has been associated with severe cardiac and central nervous system complications and even death. Viruses need host factors to complete their life cycle; therefore, the identification of the host factors for EV71 infection is pivotal to new antiviral research. Emerging evidence has highlighted the importance of protein acetylation during infection by various human viruses. The endoplasmic reticulum (ER), as the prominent organelle of EV71 replication, also has a unique acetylation regulation mechanism. However, the pathogenesis of EV71 and its relationship with the ER-based acetylation machinery are not fully understood. In this study, we demonstrated for the first time that the ER-resident acetyltransferase N-acetyltransferase 8 (NAT8) is a host factor for EV71 infection. Inhibiting NAT8 with CRISPR or a small compound significantly suppressed EV71 infection in SK-N-SH cells. NAT8 promoted EV71 replication in an acetyltransferase-activity-dependent manner. Additionally, we found that NAT8 facilitates EV71 infection by interacting with EV71 2B, 3AB, and 3C proteins and increasing the stability of these proteins. These results uncovered a novel function of NAT8 and elucidated a new mechanism underlying the regulation of EV71 replication. IMPORTANCE EV71 is one of the most common pathogens causing HFMD in young children, and some patients experience severe or fatal neurological consequences. To ensure efficient replication, the virus must hijack multiple host factors for its own benefit. Here, we show that the ER-resident acetyltransferase NAT8 is a host factor for EV71 infection. EV71 fails to complete its infection in various cells in the absence of NAT8. We further show that NAT8 benefits EV71 replication in an acetyltransferase-activity-dependent manner. Finally, we show that NAT8 facilitates EV71 infection by interacting with EV71 2B, 3AB, and 3C proteins and increasing the stability of these proteins. These results uncovered a novel function of NAT8 in EV71 infection and elucidated a new mechanism underlying the regulation of EV71 replication.


Assuntos
Acetiltransferases , Enterovirus Humano A , Infecções por Enterovirus , Proteínas não Estruturais Virais , Replicação Viral , Acetiltransferases/metabolismo , Enterovirus Humano A/fisiologia , Humanos , Proteínas não Estruturais Virais/metabolismo
7.
Int J Mol Sci ; 24(4)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36835162

RESUMO

As the greatest defense organ of the body, the skin is exposed to endogenous and external stressors that produce reactive oxygen species (ROS). When the antioxidant system of the body fails to eliminate ROS, oxidative stress is initiated, which results in skin cellular senescence, inflammation, and cancer. Two main possible mechanisms underlie oxidative stress-induced skin cellular senescence, inflammation, and cancer. One mechanism is that ROS directly degrade biological macromolecules, including proteins, DNA, and lipids, that are essential for cell metabolism, survival, and genetics. Another one is that ROS mediate signaling pathways, such as MAPK, JAK/STAT, PI3K/AKT/mTOR, NF-κB, Nrf2, and SIRT1/FOXO, affecting cytokine release and enzyme expression. As natural antioxidants, plant polyphenols are safe and exhibit a therapeutic potential. We here discuss in detail the therapeutic potential of selected polyphenolic compounds and outline relevant molecular targets. Polyphenols selected here for study according to their structural classification include curcumin, catechins, resveratrol, quercetin, ellagic acid, and procyanidins. Finally, the latest delivery of plant polyphenols to the skin (taking curcumin as an example) and the current status of clinical research are summarized, providing a theoretical foundation for future clinical research and the generation of new pharmaceuticals and cosmetics.


Assuntos
Carcinogênese , Senescência Celular , Inflamação , Estresse Oxidativo , Polifenóis , Humanos , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Senescência Celular/fisiologia , Curcumina/farmacologia , Inflamação/metabolismo , Neoplasias/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo
8.
Protein Expr Purif ; 195-196: 106080, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35304262

RESUMO

This study aimed to develop an effective method for the expression and purification of the Dermatophagoides farinae serpin protein and to establish an experimental foundation for elucidating its role in the temperature stress response. The total RNA of D. farinae was extracted, and specific primers were designed for serpin amplification. Serpin was joined with pET32a vector and transformed into BL21 (DE3) cells. Expression of recombinant proteins was induced. Proteins were extracted by enzymatic lysis or enzymatic lysis combined with ultrasonication. Recombinant proteins were purified by Ni-NTA method. SDS-PAGE was conducted to evaluate protein expression, extraction, and purification efficiency. Agarose gel electrophoresis and sequencing analysis showed that the amplified serpin open reading frame was 1284 bp, encoding a hydrophilic and stable protein with a relative molecular weight of 48.30 kD. SDS-PAGE demonstrated that there was a specific band at 55-70 kD, which was consistent with the predicted size of the recombinant pET32a-Serpin protein. Enzymatic lysis combined with 30% ultrasonic power promoted the release of soluble protein more effectively than enzymatic lysis alone. 16 °C for 4 h was optimal for inducing expression. The optimal imidazole concentrations for washing non-His-tagged protein and eluting His-tagged protein were determined to be 20 mM and 200 mM, respectively. In this study, A prokaryotic expression and purification system for the D. farinae serpin protein was successfully established, providing a technical reference for functional gene research in mites at the protein level.


Assuntos
Dermatophagoides farinae , Serpinas , Animais , Clonagem Molecular , Dermatophagoides farinae/genética , Proteínas Recombinantes/genética , Serpinas/genética
9.
Molecules ; 27(6)2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35335279

RESUMO

In this study, ultrasonic-assisted cellulase extraction (UCE) was applied to extract flavonoids and polyphenols from the Nymphaea hybrid flower. The extraction conditions were optimized using the response surface method (RSM) coupled with a Box-Behnken design. The crude extract of Nymphaea hybrid (NHE) was further purified using AB-8 macroporous resins, and the purified extract (NHEP) was characterized by FTIR and HPLC. In vitro activity determination by chemical method showed that NHEP displayed strong free radical scavenging abilities against the DPPH and ABTS radicals, good reduction power, and hyaluronidase inhibition. The cell viability by CCK-8 assays showed that NHEP had no significant cytotoxicity for B16 and HaCaT cells when the concentration was below 100 µg/mL and 120 µg/mL, respectively. NHEP with a concentration of 20-160 µg/mL can more effectively reduce the ROS level in H2O2 damaged HaCaT cells compared with 10 µg/mL of VC. The 40 µg/mL of NHEP had similar activity against intracellular melanin production in the B16 melanoma cells compared with 20 µg/mL Kojic acid. Good activities of antioxidation, whitening and protective effect against H2O2-induced oxidative damage promote the potential for NHEP as a functional raw material in the field of cosmetics and medicine.


Assuntos
Celulase , Nymphaea , Antioxidantes/química , Antioxidantes/farmacologia , Flores , Células HaCaT , Humanos , Peróxido de Hidrogênio/farmacologia , Melaninas , Estresse Oxidativo , Espécies Reativas de Oxigênio
10.
Microb Pathog ; 155: 104922, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33932545

RESUMO

Acinetobacter baumannii is an important pathogen in clinical. The factors of biofilm formation, antibiotic resistance and motility contribute great to A. baumannii in persisting in stressed environment, and further leads to nosocomial infections. 70 A. baumannii clinical isolates were investigated for their clinical characteristics of infection. Among the tested strains, 54 (77.1%) isolates were obtained from ICUs, with the frequency of multidrug-resistance (MDR) at 55.7%, and that of extensively drug-resistance (XDR) at 31.4%. 97.1% of the clinical isolates could form biofilms, in which 4.3% possessed weak biofilm formation ability, while 41.4% and 51.4% were moderate and strong biofilm producers, respectively. A strong correlation between antibiotic resistance and biofilm formation ability was found that all the resistant strains could form biofilms, with the majority in moderate and strong levels, but 2.9% sensitive isolates had no such ability. However, the sensitive strains that could produce biofilms showed stronger biofilm formation capacity in the early stage before 24 h compared to the resistant isolates, though they became weaker afterwards. 24 biofilm-related genes and two blaOXA genes were found in both biofilm-forming and non-biofilm-forming strains, but with higher prevalence in the strains that could produce biofilms. No correlation was detected between twitching motility with antibiotic susceptibility or biofilm formation. These results raised a viewpoint that examining timepoint is a key factor for determining the biofilm formation ability, and further highlighted the importance of the appropriate surveillance and control measures in preventing the emergence and transmission of MDR and XDR A. baumannii.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Acinetobacter baumannii/genética , Antibacterianos/farmacologia , Biofilmes , Farmacorresistência Bacteriana Múltipla/genética , Humanos
12.
Opt Express ; 27(2): 774-782, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30696158

RESUMO

We apply the antenna coherence theory in order to evaluate characteristic behavior of phase-coherent VCSEL arrays. Large 19-element phase-locked VCSEL arrays with a near-diffraction-limited beam were firstly realized using proton implantation technology. The central lobe intensity is about four times that of side lobes in far-field patterns. The angular full width at half maximum (FWHM) of the far field lobes is only 1.42 degrees. A good matching between theory and experiment opens new perspectives for optimizing devices.

13.
Toxicol Appl Pharmacol ; 349: 62-71, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29702141

RESUMO

Na+-K+-ATPase has close relationship with myocardial ischemia/reperfusion (IR) injury. Activation of Na+-K+-ATPase with its DR region specific antibody produces cardioprotective effect. In this study, we aimed to explore whether DRm217, a proved DR region specific antibody, could protect myocardial cells against IR injury and uncover the mechanisms under it. By employing H9c2 myocardial cell and SD rat, we found that DRm217 protected cardiac cells against IR-induced cell injury and apoptosis. DRm217 produced protective effect via stabilizing Na+-K+-ATPase membrane expression and inhibiting Na+-K+-ATPase/Src/NADPH oxidase dependent ROS accumulation. PI3K/Akt and ERK1/2 participated in DRm217-induced cardiomyocyte survival, but not in DRm217-related ROS reduction. Therefore, DRm217 can be used as a potential cardioprotective adjuvant in myocardial IR therapy and interference of Na+-K+-ATPase/ROS pathway will be a promising modality for clinical myocardial IR therapy.


Assuntos
Cardiotônicos/farmacologia , Membrana Celular/enzimologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Redes e Vias Metabólicas/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
14.
Exp Cell Res ; 357(2): 243-251, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28551376

RESUMO

Depressed Na+/K+-ATPase activity has long been reported to be involved in diabetic-related cardiomyocyte death and cardiac dysfunction. However, the nature of directly regulating Na+-K+-ATPase in diabetic-related myocardial diseases remains unknown. Hyperglycemia is believed as one of major factors responsible for diabetic-related myocardial apoptosis and dysfunction. In this study, whether inhibiting Na+-K+-ATPase by ouabain or activating Na+-K+-ATPase by DRm217 has functions on high glucose (HG) -induced myocardial injury was investigated. Here we found that addition of DRm217 or ouabain to HG-treated cells had opposite effects. DRm217 decreased but ouabain increased HG-induced cell injury and apoptosis. This was mediated by changing Na+-K+-ATPase activity and Na+-K+-ATPase cell surface expression. The inhibition of Na+-K+-ATPase endocytosis alleviated HG-induced ROS accumulation. Na+-K+-ATPase·c-Src dependent NADPH oxidase/ROS pathway was also involved in the effects of ouabain and DRm217 on HG-induced cell injury. These novel results may help us to understand the important role of the Na+-K+-ATPase in diabetic cardiovascular diseases.


Assuntos
Miócitos Cardíacos/metabolismo , Transdução de Sinais , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Apoptose/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , Endocitose/efeitos dos fármacos , Glucose/farmacologia , Transporte de Íons/efeitos dos fármacos , Miocárdio/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , NADPH Oxidases/metabolismo , Ouabaína/farmacologia , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
15.
Apoptosis ; 22(4): 531-543, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28181111

RESUMO

Reduced Na+-K+-ATPase activity has close relationship with cardiomyocyte death. Reactive oxygen species (ROS) also plays an important role in cardiac cell damage. It has been proved that Na+-K+-ATPase and ROS form a feed-forward amplifier. The aim of this study was to explore whether DRm217, a proved Na+/K+-ATPase's DR-region specific monoclonal antibody and direct activator, could disrupt Na+-K+-ATPase/ROS amplifier and protect cardiac cells from ROS-induced injury. We found that DRm217 protected myocardial cells against hydrogen peroxide (H2O2)-induced cardiac cell injury and mitochondrial dysfunction. DRm217 also alleviated the effect of H2O2 on inhibition of Na+-K+-ATPase activity, Na+-K+-ATPase cell surface expression, and Src phosphorylation. H2O2-treatment increased intracellular ROS, mitochondrial ROS and induced intracellular Ca2+, mitochondrial Ca2+ overload. DRm217 closed Na+-K+-ATPase/ROS amplifier, alleviated Ca2+ accumulation and finally inhibited ROS and mitochondrial ROS generation. These novel results may help us to understand the important role of the Na+-K+-ATPase in oxidative stress and oxidative stress-related disease.


Assuntos
Anticorpos Monoclonais/farmacologia , Mioblastos/enzimologia , Miócitos Cardíacos/enzimologia , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , ATPase Trocadora de Sódio-Potássio/fisiologia , Animais , Anticorpos Monoclonais/imunologia , Sinalização do Cálcio , Linhagem Celular , Ativação Enzimática/imunologia , Humanos , Peróxido de Hidrogênio/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/fisiologia , Camundongos , Mioblastos/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Técnicas de Cultura de Órgãos , Fosforilação , Processamento de Proteína Pós-Traducional , Ratos , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , ATPase Trocadora de Sódio-Potássio/imunologia , Quinases da Família src/fisiologia
16.
Tumour Biol ; 39(5): 1010428317701645, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28459204

RESUMO

Although gene therapy has brought new insights into the treatment of malignant melanoma, targeting delivery of nucleic acid which targets critical oncogene/anti-oncogene in vivo is still a bottleneck in the therapeutic application. Our previous in vitro studies have found that the oncogene Livin could serve as a potential molecular target by small interfering RNA for gene therapy of malignant melanoma. However, how to transport Livin small interfering RNA into malignant melanoma cells specifically and efficiently in vivo needs further investigation. Cumulative evidence has suggested that single-chain antibody-mediated small interfering RNA targeted delivery is an effective way to silence specific genes in human cancer cells. Indeed, this study designed a protamine-single-chain antibody fusion protein, anti-MM scFv-tP, to deliver Livin small interfering RNA into LiBr cells. Further experiments confirmed the induction of cell apoptosis and suppression of cell proliferation by anti-MM scFv-tP in LiBr cells, along with efficient silence of Livin gene both in vitro and in vivo. Altogether, our findings provide a feasible approach to transport Livin small interfering RNA to malignant melanoma cells which would be a new therapeutic strategy for combating malignant melanoma.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Carcinogênese/genética , Proteínas Inibidoras de Apoptose/genética , Melanoma/terapia , Terapia de Alvo Molecular , Proteínas de Neoplasias/genética , RNA Interferente Pequeno/uso terapêutico , Proteínas Adaptadoras de Transdução de Sinal/uso terapêutico , Animais , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Terapia Genética , Humanos , Proteínas Inibidoras de Apoptose/uso terapêutico , Melanoma/genética , Melanoma/patologia , Camundongos , Proteínas de Neoplasias/uso terapêutico , RNA Interferente Pequeno/genética , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Appl Opt ; 55(20): 5439-43, 2016 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-27409323

RESUMO

Implant-defined vertical-cavity surface-emitting laser (VCSEL) arrays can be designed to operate in in-phase mode. However, the nonuniformities in fabrication process impact the resonance selection and the devices do not follow expected trends. Coherent coupling was demonstrated in three-element VCSEL arrays via phase tuning of elements. In-phase mode and out-of-phase mode were both achieved in most of the arrays. Moreover, coherent coupling can decrease the threshold current of elements in the array. Improved output power was also clearly observed when the array operated in the in-phase mode. Arbitrary phase combination of the array elements can be obtained via the phase tuning. This technology is able to improve the reproducibility and practicability of the implant-defined coherently coupled VCSEL array.

18.
Acta Biochim Biophys Sin (Shanghai) ; 48(10): 883-893, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27563007

RESUMO

Hyperglycemia is one of the major factors responsible for the myocardial apoptosis and dysfunction in diabetes. Many studies have proved that there is a close relationship between decreased Na+/K+-ATPase activity and diabetic cardiomyopathy. However, the effect of directly activated Na+/K+-ATPase on high glucose-induced myocardial injury is still unknown. Here we found that DRm217, a Na+/K+-ATPase's DR-region specific monoclonal antibody and direct activator, could prevent high glucose-induced H9c2 cell injury, reactive oxygen species (ROS) release, and mitochondrial dysfunction. High glucose-treatment decreased Na+/K+-ATPase activity and increased intracellular Ca2+ level, whereas DRm217 increased Na+/K+-ATPase activity and alleviated Ca2+ overload. Inhibition of Ca2+ overload or closing sodium calcium exchanger (NCX channel) could reverse high glucose-induced ROS increasing and cell injury. In addition, DRm217 could significantly attenuate high glucose-induced p38, JNK and ERK1/2 phosphorylation, which were involved in high glucose-induced cell injury and ROS accumulation. Our findings suggest that DRm217 may protect against the deleterious effects of high glucose in the heart. Prevention of high glucose-induced myocardial cell injury by specific Na+/K+-ATPase activator may be an attractive therapeutic option.


Assuntos
Anticorpos Monoclonais/farmacologia , Apoptose/efeitos dos fármacos , Glucose/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Western Blotting , Cálcio/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Camundongos Endogâmicos BALB C , Microscopia de Fluorescência , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , ATPase Trocadora de Sódio-Potássio/imunologia
19.
Opt Lett ; 40(10): 2349-52, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26393736

RESUMO

In-phase coherently coupled vertical cavity surface emitting laser (VCSEL) hexagonal arrays were fabricated using proton implantation. The near-field profiles, far-field profiles, and emission spectra under different injection currents were tested and analyzed. The arrays can maintain in-phase single mode in a considerably wide current range from 10 mA (I(th)) to 35 mA (3.5×I(th)), exhibiting excellent beam quality. The far-field divergence angle of the in-phase coupled array is 2.5 degrees. Approximately 29% of total power is localized in the central lobe. Compared with square structure arrays, hexagonal arrays can maintain a more stable in-phase mode because of stronger coupling among the elements. The maximum output power of 4.9 mW was obtained under pulse wave condition. The simulation of far-field was carried out to match the in-phase operation test results. The performance enhancement of the array is attainable if the condition of heat dissipation is better. The process procedure of proton implantation is relatively simple and of low cost. It can be used as an alternative to coherently coupled array implementations.

20.
Virol J ; 12: 56, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25889836

RESUMO

BACKGROUND: Enterovirus 71 (EV71) is one of the major etiological pathogens of hand, foot and mouth disease (HFMD) and can cause severe cerebral and pulmonary complications and even fatality. MicroRNAs (miRNAs), a class of small non-coding RNA molecules, play an important role in post-transcriptional regulation of gene expression and thereby influencing various physiological and pathological processes. Increasing evidence suggests that miRNAs act as key effector molecules in the complicated pathogen-host interactions. However, the roles of miRNAs in EV71 infection and pathogenesis are not well understood. METHODS: To identify special miRNAs involved in EV71 infection, a microarray assay was performed to study the expression pattern of miRNAs in EV71-infected human rhabdomyosarcoma cells (RD cells) and uninfected RD cells. We further predicted the putative target genes for the dysregulated miRNAs using the online bioinformatic algorithms (TargetScan, miRanda and PicTar) and carried out functional annotation including GO enrichment and KEGG pathway analysis for miRNA predicted targets. Then, the results of microarray were further confirmed by quantitative RT-PCR. RESULTS: Totally, 45 differentially expressed miRNAs ware identified by microarray, among which 36 miRNAs were up-regulated and 9 were down-regulated. 7166 predicted target genes for the dysregulated miRNAs were revealed by using TargetScan in conjunction with miRanda and PicTar. The GO annotation suggested that predicted targets of miRNAs were enriched into the category of signal transduction, regulation of transcription, metabolic process, protein phosphorylation, apoptotic process and immune response. KEGG pathway analysis suggested that these predicted target genes were involved in many important pathways, mainly including endocytosis and focal adhesion, MAPK signaling pathway, hypertrophic cardiomyopathy, melanogenesis and ErbB signaling pathway. The expression levels of 8 most differentially up-regulated miRNAs and 3 most differentially down-regulated miRNAs were confirmed by qRT-PCR. The expressions of hsa-miR-4530, hsa-miR-4492, hsa-miR-6125, hsa-miR-494-3p, hsa-miR-638, hsa-miR-6743-5p, hsa-miR-4459 and hsa-miR-4443 detected by qRT-PCR were consistent with the microarray data. CONCLUSION: These results might extend our understanding to the regulatory mechanism of miRNAs underlying the pathogenesis of EV71 infection, thus strengthening the preventative and therapeutic strategies of HFMD caused by EV71.


Assuntos
Enterovirus Humano A/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno , MicroRNAs/biossíntese , Linhagem Celular Tumoral , Biologia Computacional , Perfilação da Expressão Gênica , Humanos , MicroRNAs/genética , Análise em Microsséries , Reação em Cadeia da Polimerase em Tempo Real
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