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1.
Small ; 20(27): e2307210, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38279606

RESUMO

Sepsis is a life-threatening condition that can progress to septic shock as the body's extreme response to pathogenesis damages its own vital organs. Staphylococcus aureus (S. aureus) accounts for 50% of nosocomial infections, which are clinically treated with antibiotics. However, methicillin-resistant strains (MRSA) have emerged and can withstand harsh antibiotic treatment. To address this problem, curcumin (CCM) is employed to prepare carbonized polymer dots (CPDs) through mild pyrolysis. Contrary to curcumin, the as-formed CCM-CPDs are highly biocompatible and soluble in aqueous solution. Most importantly, the CCM-CPDs induce the release of neutrophil extracellular traps (NETs) from the neutrophils, which entrap and eliminate microbes. In an MRSA-induced septic mouse model, it is observed that CCM-CPDs efficiently suppress bacterial colonization. Moreover, the intrinsic antioxidative, anti-inflammatory, and anticoagulation activities resulting from the preserved functional groups of the precursor molecule on the CCM-CPDs prevent progression to severe sepsis. As a result, infected mice treated with CCM-CPDs show a significant decrease in mortality even through oral administration. Histological staining indicates negligible organ damage in the MRSA-infected mice treated with CCM-CPDs. It is believed that the in vivo studies presented herein demonstrate that multifunctional therapeutic CPDs hold great potential against life-threatening infectious diseases.


Assuntos
Armadilhas Extracelulares , Staphylococcus aureus Resistente à Meticilina , Polímeros , Sepse , Animais , Sepse/tratamento farmacológico , Armadilhas Extracelulares/efeitos dos fármacos , Polímeros/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Neutrófilos/efeitos dos fármacos , Carbono/química , Carbono/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Curcumina/farmacologia , Curcumina/uso terapêutico , Curcumina/química , Humanos
2.
Nano Lett ; 23(11): 4916-4922, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37257060

RESUMO

Understanding and characterizing the mechanical behavior of colloidal nanocrystal (NC) assemblies are important for developing nanocrystalline materials with exceptional mechanical properties for robust electronic, thermoelectric, photovoltaic, and optoelectronic devices. However, the limited ranges of Young's modulus, hardness, and fracture toughness (≲1-10 GPa, ≲50-500 MPa, and ≲10-50 kPa m1/2, respectively) in as-synthesized NC assemblies present challenges for their mechanical stability and therefore their practical applications. In this work, we demonstrate using a combination of nanoindentation measurements and coarse-grained modeling that the mechanical response of assemblies of as-synthesized NCs is governed by the van der Waals interactions of the organic surface ligands. More importantly, we report tremendous ∼60× enhancements in Young's modulus and hardness and an ∼80× enhancement in fracture toughness of CdSe NC assemblies through a simple inorganic Sn2S64- ligand exchange process. Moreover, our observation of softening in nanocrystalline materials with decreasing CdSe NC diameter is consistent with atomistic simulations.

3.
Int J Mol Sci ; 25(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38256117

RESUMO

Atherosclerosis is an inflammatory disease of the arteries associated with alterations in lipid and other metabolism and is a major cause of cardiovascular disease (CVD). LDL consists of several subclasses with different sizes, densities, and physicochemical compositions. Small dense LDL (sd-LDL) is a subclass of LDL. There is growing evidence that sd-LDL-C is associated with CVD risk, metabolic dysregulation, and several pathophysiological processes. In this study, we present a straightforward membrane device filtration method that can be performed with simple laboratory methods to directly determine sd-LDL in serum without the need for specialized equipment. The method consists of three steps: first, the precipitation of lipoproteins with magnesium harpin; second, the collection of effluent from a 100 nm filter; and third, the quantification of sd-LDL-ApoB in the effluent with an SH-SAW biosensor. There was a good correlation between ApoB values obtained using the centrifugation (y = 1.0411x + 12.96, r = 0.82, n = 20) and filtration (y = 1.0633x + 15.13, r = 0.88, n = 20) methods and commercially available sd-LDL-C assay values. In addition to the filtrate method, there was also a close correlation between sd-LDL-C and ELISA assay values (y = 1.0483x - 4489, r = 0.88, n = 20). The filtration treatment method also showed a high correlation with LDL subfractions and NMR spectra ApoB measurements (y = 2.4846x + 4.637, r = 0.89, n = 20). The presence of sd-LDL-ApoB in the effluent was also confirmed by ELISA assay. These results suggest that this filtration method is a simple and promising pretreatment for use with the SH-SAW biosensor as a rapid in vitro diagnostic (IVD) method for predicting sd-LDL concentrations. Overall, we propose a very sensitive and specific SH-SAW biosensor with the ApoB antibody in its sensitive region to monitor sd-LDL levels by employing a simple delay-time phase shifted SH-SAW device. In conclusion, based on the demonstration of our study, the SH-SAW biosensor could be a strong candidate for the future measurement of sd-LDL.


Assuntos
Antígenos de Grupos Sanguíneos , Doenças Cardiovasculares , Humanos , LDL-Colesterol , Tecnologia , Anticorpos , Artérias
4.
J Biol Chem ; 298(6): 101957, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35452675

RESUMO

Japanese encephalitis is a mosquito-borne disease caused by the Japanese encephalitis virus (JEV) that is prevalent in Asia and the Western Pacific. Currently, there is no effective treatment for Japanese encephalitis. Curcumin (Cur) is a compound extracted from the roots of Curcuma longa, and many studies have reported its antiviral and anti-inflammatory activities. However, the high cytotoxicity and very low solubility of Cur limit its biomedical applications. In this study, Cur carbon quantum dots (Cur-CQDs) were synthesized by mild pyrolysis-induced polymerization and carbonization, leading to higher water solubility and lower cytotoxicity, as well as superior antiviral activity against JEV infection. We found that Cur-CQDs effectively bound to the E protein of JEV, preventing viral entry into the host cells. In addition, after continued treatment of JEV with Cur-CQDs, a mutant strain of JEV was evolved that did not support binding of Cur-CQDs to the JEV envelope. Using transmission electron microscopy, biolayer interferometry, and molecular docking analysis, we revealed that the S123R and K312R mutations in the E protein play a key role in binding Cur-CQDs. The S123 and K312 residues are located in structural domains II and III of the E protein, respectively, and are responsible for binding to receptors on and fusing with the cell membrane. Taken together, our results suggest that the E protein of flaviviruses represents a potential target for the development of CQD-based inhibitors to prevent or treat viral infections.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Pontos Quânticos , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Carbono , Vírus da Encefalite Japonesa (Espécie)/química , Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/tratamento farmacológico , Simulação de Acoplamento Molecular , Proteínas do Envelope Viral/metabolismo
5.
J Med Virol ; 95(11): e29243, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-38009231

RESUMO

The fight against hand, foot, and mouth disease (HFMD) remains an arduous challenge without existing point-of-care (POC) diagnostic platforms for accurate diagnosis and prompt case quarantine. Hence, the purpose of this salivary biomarker discovery study is to set the fundamentals for the realization of POC diagnostics for HFMD. Whole salivary proteome profiling was performed on the saliva obtained from children with HFMD and healthy children, using a reductive dimethylation chemical labeling method coupled with high-resolution mass spectrometry-based quantitative proteomics technology. We identified 19 upregulated (fold change = 1.5-5.8) and 51 downregulated proteins (fold change = 0.1-0.6) in the saliva samples of HFMD patients in comparison to that of healthy volunteers. Four upregulated protein candidates were selected for dot blot-based validation assay, based on novelty as biomarkers and exclusions in oral diseases and cancers. Salivary legumain was validated in the Singapore (n = 43 healthy, 28 HFMD cases) and Taiwan (n = 60 healthy, 47 HFMD cases) cohorts with an area under the receiver operating characteristic curve of 0.7583 and 0.8028, respectively. This study demonstrates the feasibility of a broad-spectrum HFMD POC diagnostic test based on legumain, a virus-specific host systemic signature, in saliva.


Assuntos
Doença de Mão, Pé e Boca , Criança , Humanos , Doença de Mão, Pé e Boca/diagnóstico , Biomarcadores/metabolismo , Cisteína Endopeptidases/genética , Curva ROC
6.
Nano Lett ; 22(12): 4669-4676, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35639612

RESUMO

Colloidal nanocrystal (NC) assemblies are promising for optoelectronic, photovoltaic, and thermoelectric applications. However, using these materials can be challenging in actual devices because they have a limited range of thermal conductivity and elastic modulus, which results in heat dissipation and mechanical robustness challenges. Here, we report thermal transport and mechanical measurements on single-domain colloidal PbS nanocrystal superlattices (NCSLs) that have long-range order as well as measurements on nanocrystal films (NCFs) that are comparatively disordered. Over an NC diameter range of 3.0-6.1 nm, we observe that NCSLs have thermal conductivities and Young's moduli that are up to ∼3 times higher than those of the corresponding NCFs. We also find that these properties are more sensitive to NC diameter in NCSLs relative to NCFs. Our measurements and computational modeling indicate that stronger ligand-ligand interactions due to enhanced ligand interdigitation and alignment in NCSLs account for the improved thermal transport and mechanical properties.


Assuntos
Nanopartículas , Ligantes , Nanopartículas/química
7.
Langmuir ; 38(43): 13279-13287, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36256617

RESUMO

Gallium-based liquid metals (LMs) combine metallic properties with the deformability of a liquid, which makes them promising candidates for a variety of applications. To broaden the range of physical and chemical properties, a variety of solid additives have been incorporated into the LMs in the literature. In contrast, only a handful of secondary fluids have been incorporated into LMs to create foams (gas-in-LM) or emulsions (liquid-in-LM). LM foams readily form through mixing of LM in air, facilitated by the formation of a native oxide on the LM. In contrast, LM breaks up into microdroplets when mixed with a secondary liquid such as silicone oil. Stable silicone oil-in-LM emulsions form only during mixing of the oil with LM foam. In this work, we investigate the fundamental mechanism underlying this process. We describe two possible microscale mechanisms for emulsion formation: (1) oil replacing air in the foam or (2) oil creating additional features in the foam. The associated foam-to-emulsion density difference demonstrates that emulsions predominantly form through the addition of oxide-covered silicone oil capsules to the LM foam. We demonstrate this through density and surface wettability measurements and multiscale imaging of LM foam mixed with varied silicone oil contents in air or nitrogen environments. We also demonstrate the presence of a continuous silicone oil film on the emulsion surface and that this oil film prevents the embrittlement of contacting aluminum.

8.
Soft Matter ; 17(36): 8269-8275, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34397076

RESUMO

Gallium based liquid metals (LM) have prospective biomedical, stretchable electronics, soft robotics, and energy storage applications, and are being widely adopted as thermal interface materials. The danger of gallium corroding most metals used in microelectronics requires the cumbersome addition of "barrier" layers or LM break-up into droplets within an inert matrix such as silicone oil. Such LM-in-oil emulsions are stabilized by native oxide on the droplets but have decreased thermal performance. Here we show that mixing of the silicone oil into an LM-air foam yields emulsions with inverted phases. We investigate the stability of these oil-in-LM emulsions through a range of processing times and oil viscosities, and characterize the impact of these parameters on the materials' structure and thermal property relationships. We demonstrate that the emulsion with 40 vol% of 10 cSt silicone oil provides a unique thermal management material with a 10 W m-1 K-1 thermal conductivity and an exterior lubricant thin film that completely prevents corrosion of contacting aluminum.

9.
J Virol ; 93(10)2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30814289

RESUMO

Infection by enteroviruses can cause severe neurological complications in humans. The interactions between the enteroviral and host proteins may facilitate the virus replication and be involved in the pathogenicity of infected individuals. It has been shown that human enteroviruses possess various mechanisms to suppress host innate immune responses in infected cells. Previous studies showed that infection by enterovirus 71 (EV71) causes the degradation of MDA5, which is a critical cytoplasmic pathogen sensor in the recognition of picornaviruses for initiating transcription of type I interferons. In the present study, we demonstrated that the RNA-dependent RNA polymerase (RdRP; also denoted 3Dpol) encoded by EV71 interacts with the caspase activation and recruitment domains (CARDs) of MDA5 and plays a role in the inhibition of MDA5-mediated beta interferon (IFN-ß) promoter activation and mRNA expression. In addition, we found that the 3Dpol protein encoded by coxsackievirus B3 also interacted with MDA5 and downregulated the antiviral signaling initiated by MDA5. These findings indicate that enteroviral RdRP may function as an antagonist against the host antiviral innate immune response.IMPORTANCE Infection by enteroviruses causes severe neurological complications in humans. Human enteroviruses possess various mechanisms to suppress the host type I interferon (IFN) response in infected cells to establish viral replication. In the present study, we found that the enteroviral 3Dpol protein (or RdRP), which is a viral RNA-dependent RNA polymerase for replicating viral RNA, plays a role in the inhibition of MDA5-mediated beta interferon (IFN-ß) promoter activation. We further demonstrated that enteroviral 3Dpol protein interacts with the caspase activation and recruitment domains (CARDs) of MDA5. These findings indicate that enteroviral RdRP functions as an antagonist against the host antiviral response.


Assuntos
Enterovirus Humano A/metabolismo , Helicase IFIH1 Induzida por Interferon/metabolismo , RNA Polimerase Dependente de RNA/metabolismo , Domínio de Ativação e Recrutamento de Caspases/genética , Domínio de Ativação e Recrutamento de Caspases/fisiologia , Enterovirus/genética , Enterovirus/metabolismo , Enterovirus Humano A/genética , Enterovirus Humano B/metabolismo , Infecções por Enterovirus/virologia , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Interferon Tipo I/metabolismo , Helicase IFIH1 Induzida por Interferon/genética , Interferon beta/metabolismo , Interferons/metabolismo , Interferons/fisiologia , RNA Viral/genética , RNA Polimerase Dependente de RNA/genética , Transdução de Sinais , Replicação Viral
10.
PLoS Pathog ; 14(5): e1007086, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29782554

RESUMO

RNA viruses induce specialized membranous structures for use in genome replication. These structures are often referred to as replication organelles (ROs). ROs exhibit distinct lipid composition relative to other cellular membranes. In many picornaviruses, phosphatidylinositol-4-phosphate (PI4P) is a marker of the RO. Studies to date indicate that the viral 3A protein hijacks a PI4 kinase to induce PI4P by a mechanism unrelated to the cellular pathway, which requires Golgi-specific brefeldin A-resistance guanine nucleotide exchange factor 1, GBF1, and ADP ribosylation factor 1, Arf1. Here we show that a picornaviral 3CD protein is sufficient to induce synthesis of not only PI4P but also phosphatidylinositol-4,5-bisphosphate (PIP2) and phosphatidylcholine (PC). Synthesis of PI4P requires GBF1 and Arf1. We identified 3CD derivatives: 3CDm and 3CmD, that we used to show that distinct domains of 3CD function upstream of GBF1 and downstream of Arf1 activation. These same 3CD derivatives still supported induction of PIP2 and PC, suggesting that pathways and corresponding mechanisms used to induce these phospholipids are distinct. Phospholipid induction by 3CD is localized to the perinuclear region of the cell, the outcome of which is the proliferation of membranes in this area of the cell. We conclude that a single viral protein can serve as a master regulator of cellular phospholipid and membrane biogenesis, likely by commandeering normal cellular pathways.


Assuntos
Peptídeo Hidrolases/metabolismo , Fosfolipídeos/biossíntese , Picornaviridae/enzimologia , Proteínas Virais/metabolismo , Fator 1 de Ribosilação do ADP/metabolismo , Brefeldina A/farmacologia , Membrana Celular/ultraestrutura , Dactinomicina/farmacologia , Complexo de Golgi/efeitos dos fármacos , Complexo de Golgi/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Células HeLa , Humanos , Microscopia Eletrônica de Transmissão , Biogênese de Organelas , Fosfatos de Fosfatidilinositol/metabolismo , Poliovirus/enzimologia , Inibidores da Síntese de Proteínas/farmacologia , Piridinas/farmacologia , Quinolinas/farmacologia
11.
J Biomed Sci ; 27(1): 22, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31910851

RESUMO

Upon EV-A71 infection of a host cell, EV-A71 RNA is translated into a viral polyprotein. Although EV-A71 can use the cellular translation machinery to produce viral proteins, unlike cellular translation, which is cap-dependent, the viral RNA genome of EV-A71 does not contain a 5' cap and the translation of EV-A71 protein is cap-independent, which is mediated by the internal ribosomal entry site (IRES) located in the 5' UTR of EV-A71 mRNA. Like many other eukaryotic viruses, EV-A71 manipulates the host cell translation devices, using an elegant RNA-centric strategy in infected cells. During viral translation, viral RNA plays an important role in controlling the stage of protein synthesis. In addition, due to the cellular defense mechanism, viral replication is limited by down-regulating translation. EV-A71 also utilizes protein factors in the host to overcome antiviral responses or even use them to promote viral translation rather than host cell translation. In this review, we provide an introduction to the known strategies for EV-A71 to exploit cellular translation mechanisms.


Assuntos
Enterovirus Humano A/fisiologia , Infecções por Enterovirus/metabolismo , Regulação Viral da Expressão Gênica/fisiologia , Sítios Internos de Entrada Ribossomal , Biossíntese de Proteínas/fisiologia , RNA Viral/metabolismo , Humanos
12.
Virol J ; 17(1): 21, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024541

RESUMO

BACKGROUND: Human enterovirus 71 (EV-A71) is a non-enveloped virus that has a single stranded positive sense RNA genome. In a previous study, we showed that miR-876-5p upregulation was observed in the serum of patients with severe EV-A71 infection. Micro-876-5p (miR-876-5p) is a circulating miRNA that can be identified to modulate EV-A71 infections through both in vitro and in vivo studies. However, the regulatory mechanisms that involve miR-876-5p in the EV-A71 infection cycle remain unclear. METHODS: We demonstrated that miR-876-5p facilitated EV-A71 replication and expression by overexpression and knocking-down of miR-876-5p through the transfection of miR-876-5p plasmid and miR-876-5p inhibitor. Although miR-876-5p suppressed CREB5 expression, luciferase reporter assay confirmed this. We also evaluated the role of miR-876-5p in the EV-A71 infection cycle by CREB5 mediated by transfection with an anti-miR-876-5P inhibitor or in combination with an si-CREB5 plasmid. RESULTS: MicroR-876-5p was upregulated in EV-A71-infected neuroblastoma cells. Overexpression of miR-876-5p or knockdown of cyclic-AMP responsive element binding protein 5 (CREB5) promoted EV-A71 replication. The downregulation of miR-876-5p inhibited the accumulation of viral RNA and the production of viral proteins. Interestingly, CREB5 overexpression also suppressed EV-A71 replication. Our in vitro studies reveal that miR-876-5p directly targets CREB5. Finally, downregulation of CREB5 protein abated the inhibitory effect of anti-miR-876-5p and induced inhibitory effect of EV-A71 replication. CONCLUSIONS: Our results suggest that intracellular miR-876-5p promotes EV-A71 replication indirectly by targeting the host CREB5 protein.


Assuntos
Enterovirus Humano A/fisiologia , Interações entre Hospedeiro e Microrganismos/genética , MicroRNAs/genética , Replicação Viral , Animais , Antivirais , Linhagem Celular Tumoral , Proteína A de Ligação a Elemento de Resposta do AMP Cíclico/genética , Regulação para Baixo , Enterovirus Humano A/genética , Humanos , Camundongos , Camundongos Endogâmicos ICR , Neuroblastoma , Organismos Livres de Patógenos Específicos
13.
Soft Matter ; 16(25): 5801-5805, 2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32436530

RESUMO

Foaming of gallium-based liquid metals improves their processability and-seemingly in contrast to processing of other metal foams-can be achieved through shear-mixing in air without addition of solid microparticles. Resolving this discrepancy, systematic processing-structure-property characterization demonstrates that many crumpled oxide particles are generated prior to air bubble accumulation.

14.
Angew Chem Int Ed Engl ; 59(24): 9556-9563, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32107835

RESUMO

The ongoing interest in colloidal nanocrystal solids for electronic and photonic devices necessitates that their thermal-transport properties be well understood because heat dissipation frequently limits performance in these devices. Unfortunately, colloidal nanocrystal solids generally possess very low thermal conductivities. This very low thermal conductivity primarily results from the weak van der Waals interaction between the ligands of adjacent nanocrystals. We overcome this thermal-transport bottleneck by crosslinking the ligands to exchange a weak van der Waals interaction with a strong covalent bond. We obtain thermal conductivities of up to 1.7 Wm-1 K-1 that exceed prior reported values by a factor of 4. This improvement is significant because the entire range of prior reported values themselves only span a factor of 4 (i.e., 0.1-0.4 Wm-1 K-1 ). We complement our thermal-conductivity measurements with mechanical nanoindentation measurements that demonstrate ligand crosslinking increases Young's modulus and sound velocity. This increase in sound velocity is a key bridge between mechanical and thermal properties because sound velocity and thermal conductivity are linearly proportional according to kinetic theory. Control experiments with non-crosslinkable ligands, as well as transport modeling, further confirm that ligand crosslinking boosts thermal transport.

15.
Small ; 15(41): e1902641, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31468672

RESUMO

It is demonstrated that carbon quantum dots derived from curcumin (Cur-CQDs) through one-step dry heating are effective antiviral agents against enterovirus 71 (EV71). The surface properties of Cur-CQDs, as well as their antiviral activity, are highly dependent on the heating temperature during synthesis. The one-step heating of curcumin at 180 °C preserves many of the moieties of polymeric curcumin on the surfaces of the as-synthesized Cur-CQDs, resulting in superior antiviral characteristics. It is proposed that curcumin undergoes a series of structural changes through dehydration, polymerization, and carbonization to form core-shell CQDs whose surfaces remain a pyrolytic curcumin-like polymer, boosting the antiviral activity. The results reveal that curcumin possesses insignificant inhibitory activity against EV71 infection in RD cells [half-maximal effective concentration (EC50 ) >200 µg mL-1 ] but exhibits high cytotoxicity toward RD cells (half-maximal cytotoxic concentration (CC50 ) <13 µg mL-1 ). The EC50 (0.2 µg mL-1 ) and CC50 (452.2 µg mL-1 ) of Cur-CQDs are >1000-fold lower and >34-fold higher, respectively, than those of curcumin, demonstrating their far superior antiviral capabilities and high biocompatibility. In vivo, intraperitoneal administration of Cur-CQDs significantly decreases mortality and provides protection against virus-induced hind-limb paralysis in new-born mice challenged with a lethal dose of EV71.


Assuntos
Antivirais/farmacologia , Carbono/química , Curcumina/farmacologia , Pontos Quânticos/química , Animais , Encéfalo/virologia , Morte Celular/efeitos dos fármacos , Curcumina/química , Enterovirus/efeitos dos fármacos , Fator de Iniciação Eucariótico 4G/metabolismo , Feminino , Masculino , Camundongos Endogâmicos ICR , Músculos/virologia , Fosforilação/efeitos dos fármacos , Pontos Quânticos/ultraestrutura , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Vírion/efeitos dos fármacos , Vírion/metabolismo , Difração de Raios X , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
16.
Int J Mol Sci ; 17(11)2016 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-27801783

RESUMO

Natural compounds from soft corals have been increasingly used for their antitumor therapeutic properties. This study examined 11-epi-sinulariolide acetate (11-epi-SA), an active compound isolated from the cultured soft coral Sinularia flexibilis, to determine its potential antitumor effect on four hepatocellular carcinoma cell lines. Cell viability was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and the results demonstrated that 11-epi-SA treatment showed more cytotoxic effect toward HA22T cells. Protein profiling of the 11-epi-SA-treated HA22T cells revealed substantial protein alterations associated with stress response and protein synthesis and folding, suggesting that the mitochondria and endoplasmic reticulum (ER) play roles in 11-epi-SA-initiated apoptosis. Moreover, 11-epi-SA activated caspase-dependent apoptotic cell death, suggesting that mitochondria-related apoptosis genes were involved in programmed cell death. The unfolded protein response signaling pathway-related proteins were also activated on 11-epi-SA treatment, and these changes were accompanied by the upregulated expression of growth arrest and DNA damage-inducible protein (GADD153) and CCAAT/enhancer binding protein (C/EBP) homologous protein (CHOP), the genes encoding transcription factors associated with growth arrest and apoptosis under prolonged ER stress. Two inhibitors, namely salubrinal (Sal) and SP600125, partially abrogated 11-epi-SA-related cell death, implying that the protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK)-activating transcription factor (ATF) 6-CHOP or the inositol-requiring enzyme 1 alpha (IRE1α)-c-Jun N-terminal kinase (JNK)-cJun signal pathway was activated after 11-epi-SA treatment. In general, these results suggest that 11-epi-SA exerts cytotoxic effects on HA22T cells through mitochondrial dysfunction and ER stress cell death pathways.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Diterpenos/química , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Animais , Antozoários/química , Antracenos/administração & dosagem , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Sobrevivência Celular/efeitos dos fármacos , Cinamatos/administração & dosagem , Diterpenos/administração & dosagem , Diterpenos/síntese química , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/biossíntese , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Transdução de Sinais/efeitos dos fármacos , Tioureia/administração & dosagem , Tioureia/análogos & derivados , Fator de Transcrição CHOP/biossíntese , Fator de Transcrição CHOP/genética , Resposta a Proteínas não Dobradas/efeitos dos fármacos
17.
Mar Drugs ; 12(10): 5295-315, 2014 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-25342459

RESUMO

13-acetoxysarcocrassolide (13-AC), an active compound isolated from cultured Formosa soft coral Sarcophyton crassocaule, was found to possess anti-proliferative and apoptosis-inducing activities against AGS (human gastric adenocarcinoma cells) gastric carcinoma cells. The anti-tumor effects of 13-AC were determined by MTT assay, colony formation assessment, cell wound-healing assay, TUNEL/4,6-Diamidino-2-phenylindole (DAPI) staining, Annexin V-fluorescein isothiocyanate/propidium iodide (PI) staining and flow cytometry. 13-AC inhibited the growth and migration of gastric carcinoma cells in a dose-dependent manner and induced both early and late apoptosis as assessed by flow cytometer analysis. 13-AC-induced apoptosis was confirmed through observation of a change in ΔΨm, up-regulated expression levels of Bax and Bad proteins, down-regulated expression levels of Bcl-2, Bcl-xl and Mcl-1 proteins, and the activation of caspase-3, caspase-9, p38 and JNK. Furthermore, inhibition of p38 and JNK activity by pretreatment with SB03580 (a p38-specific inhibitor) and SP600125 (a JNK-specific inhibitor) led to rescue of the cell cytotoxicity of 13-AC-treated AGS cells, indicating that the p38 and the JNK pathways are also involved in the 13-AC-induced cell apoptosis. Together, these results suggest that 13-AC induces cell apoptosis against gastric cancer cells through triggering of the mitochondrial-dependent apoptotic pathway as well as activation of the p38 and JNK pathways.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma/metabolismo , Diterpenos/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/metabolismo , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Regulação para Cima/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo , Proteína de Morte Celular Associada a bcl/metabolismo , Proteína bcl-X/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
18.
J Phys Condens Matter ; 36(42)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39025116

RESUMO

Gallium-based liquid metals (LMs) have surface tension an order of magnitude higher than water and break up into micro-droplets when mixed with other liquids. In contrast, silicone oil readily mixes into LM foams to create oil-in-LM emulsions with oil inclusions. Previously, the LM was foamed through rapid mixing in air for an extended duration (over 2 h). This process first results in the internalization of oxide flakes that form at the air-liquid interface. Once a critical fraction of these randomly shaped solid flakes is reached, air bubbles internalize into the LM to create foams that can internalize secondary liquids. Here, we introduce an alternative oil-in-LM emulsion fabrication method that relies on the prior addition of SiO2micro-particles into the LM before mixing it with the silicone oil. This particle-assisted emulsion formation process provides a higher control over the composition of the LM-particle mixture before oil addition, which we employ to systematically study the impact of particle characteristics and content on the emulsions' composition and properties. We demonstrate that the solid particle size (0.8µm to 5µm) and volume fraction (1%-10%) have a negligible impact on the internalization of the oil inclusions. The inclusions are mostly spherical with diameters of 20-100µm diameter and are internalized by forming new, rather than filling old, geometrical features. We also study the impact of the particle characteristics on the two key properties related to the functional application of the LM emulsions in the thermal management of microelectronics. In particular, we measure the impact of particles and silicone oil on the emulsion's thermal conductivity and its ability to prevent deleterious gallium-induced corrosion and embrittlement of contacting metal substrates.

19.
Cell Biol Int ; 37(12): 1308-19, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23956153

RESUMO

Foreskin fibroblast-like stromal cells (FDSCs) are progenitors isolated from human tissue that can differentiate into diverse cell types. Many types of stem cells can differentiate into hepatocyte-like cells, which could be used for drug testing or in liver regeneration therapy, but whether FDSCs can be converted into functional hepatocytes is unknown. FDSCs show divergent properties when cultured in distinct media, forming spheres in Dulbecco's modified Eagle's medium (DMEM) containing F12, epidermal growth factor (EGF), and basic fibroblast growth factor (b-FGF), but have fibroblast-like morphology when cultured in DMEM-based growth medium. Both cell populations express the typical mesenchymal stem cell markers CD90, CD105, and CD73, but the p75 neurotrophin receptor (p75NTR) was detected only in FDSC spheres. Both types of FDSCs can differentiate into hepatocyte-like cells, which express typical liver markers, including albumin and hepatocyte paraffin 1 (Hep Par1), along with liver-specific biological activities. When plasmids containing the human hepatitis B virus (HBV) genome were transfected transiently into FDSCs, differentiated hepatocyte-like cells secrete large amounts of HBe and HBs antigens. FDSCs could be used for clinical hepatic therapy and/or serve as a model of HBV.


Assuntos
Diferenciação Celular , Prepúcio do Pênis/citologia , Hepatócitos/citologia , Células Estromais/citologia , Biomarcadores/metabolismo , Células Cultivadas , Criança , Fibroblastos/citologia , Genes Virais/genética , Antígenos de Superfície da Hepatite B/metabolismo , Antígenos E da Hepatite B/metabolismo , Vírus da Hepatite B/genética , Hepatócitos/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Plasmídeos/genética , Plasmídeos/metabolismo , Células Estromais/metabolismo , Transfecção
20.
Biosensors (Basel) ; 13(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37366970

RESUMO

Point-of-care testing (POCT), also known as on-site or near-patient testing, has been exploding in the last 20 years. A favorable POCT device requires minimal sample handling (e.g., finger-prick samples, but plasma for analysis), minimal sample volume (e.g., one drop of blood), and very fast results. Shear horizontal surface acoustic wave (SH-SAW) biosensors have attracted a lot of attention as one of the effective solutions to complete whole blood measurements in less than 3 min, while providing a low-cost and small-sized device. This review provides an overview of the SH-SAW biosensor system that has been successfully commercialized for medical use. Three unique features of the system are a disposable test cartridge with an SH-SAW sensor chip, a mass-produced bio-coating, and a palm-sized reader. This paper first discusses the characteristics and performance of the SH-SAW sensor system. Subsequently, the method of cross-linking biomaterials and the analysis of SH-SAW real-time signals are investigated, and the detection range and detection limit are presented.


Assuntos
Acústica , Técnicas Biossensoriais , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Técnicas Biossensoriais/métodos , Imunoensaio/métodos , Som
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