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1.
Nat Nanotechnol ; 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959929

RESUMO

Chirality-the property of an object wherein it is distinguishable from its mirror image-is of widespread interest in chemistry and biology1-6. Regioselective magnetization of one-dimensional semiconductors enables anisotropic magnetism at room temperature, as well as the manipulation of spin polarization-the properties essential for spintronics and quantum computing technology7. To enable oriented magneto-optical functionalities, the growth of magnetic units has to be achieved at targeted locations on a parent nanorod. However, this challenge is yet to be addressed in the case of materials with a large lattice mismatch. Here, we report the regioselective magnetization of nanorods independent of lattice mismatch via buffer intermediate catalytic layers that modify interfacial energetics and promote regioselective growth of otherwise incompatible materials. Using this strategy, we combine materials with distinct lattices, chemical compositions and magnetic properties, that is, a magnetic component (Fe3O4) and a series of semiconducting nanorods absorbing across the ultraviolet and visible spectrum at specific locations. The resulting heteronanorods exhibit optical activity as induced by the location-specific magnetic field. The regioselective magnetization strategy presented here enables a path to designing optically active nanomaterials for chirality and spintronics.

2.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(11): 1133-1135, 2019 Nov 10.
Artigo em Chinês | MEDLINE | ID: mdl-31703144

RESUMO

OBJECTIVE: To identify a novel human leukocyte antigen (HLA) B allele in a Chinese Han individual and construct its three-dimensional structure. METHODS: The initial HLA genotyping was performed by PCR-sequence-based typing (PCR-SBT). The ambiguous allele was confirmed with single-strand DNA sequencing. The DNA sequence was analyzed to identify the difference between the novel allele and its closest matching allele. Finally, the three-dimensional molecular structure of the novel allele was constructed using a Swiss-Model. RESULTS: One allele of the subject at the HLA-B locus was B*44:03:01, whilst the other was a novel allele which differed from the closest matching allele B*51:01:01:01 by nucleotide (nt) 329 A to C in exon 2, resulting in an amino acid change at codon 86 (p.Asn86Thr). CONCLUSION: A novel HLA-B allele has been identified and officially named as HLA-B*51:159 by the WHO Nomenclature Committee for Factors of the HLA System. The three-dimensional structure of B*51:159 was simulated.


Assuntos
Grupo com Ancestrais do Continente Asiático , Antígenos HLA-B/química , Antígenos HLA-B/genética , Alelos , Sequência de Bases , Humanos , Conformação Molecular , Análise de Sequência de DNA
3.
ACS Nano ; 13(9): 10074-10084, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31430428

RESUMO

An in situ forming hydrogel has emerged as a promising wound dressing recently. As physically cross-linked hydrogels are normally unstable, most in situ forming hydrogels are chemically cross-linked. However, big concerns have remained regarding the slow gelation and the potential toxicity of residual functional groups from cross-linkers or the polymer matrix. Herein, we report a sprayable in situ forming hydrogel composed of poly(N-isopropylacrylamide166-co-n-butyl acrylate9)-poly(ethylene glycol)-poly(N-isopropylacrylamide166-co-n-butyl acrylate9) copolymer (P(NIPAM166-co-nBA9)-PEG-P(NIPAM166-co-nBA9), denoted as PEP) and silver-nanoparticles-decorated reduced graphene oxide nanosheets (Ag@rGO, denoted as AG) in response to skin temperature. This thermoresponsive hydrogel exhibits intriguing sol-gel irreversibility at low temperatures for the stable dressing of a wound, which is attributed to the inorganic/polymeric dual network and abundant coordination interactions between Ag@rGO nanosheets and PNIPAM. The biocompatibility and antibacterial ability against methicillin-resistant Staphylococcus aureus (MRSA) of this PEP-AG hydrogel wound dressing are confirmed in vitro and in vivo, which could transparently promote the healing of a MRSA-infected skin defect.

4.
Biomaterials ; 216: 119248, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31226569

RESUMO

Neurodegenerative disorders such as Huntington's disease (HD) are fundamentally caused by accumulation of misfolded aggregate-prone proteins. Previous investigations have shown that these toxic protein aggregates could be degraded through autophagy induced by small molecules as well as by nanomaterials. However, whether engineered nanomaterials have the capacity to degrade these protein aggregates via the ubiquitin-proteasome system (UPS), the other major pathway for intracellular protein turnover, was unknown. Herein, we have synthesized biocompatible MnFe2O4 nanoparticles (NPs) and demonstrated their unique effect in accelerating the clearance of mutant huntingtin (Htt) protein exhibiting 74 glutamine repeats [Htt(Q74)]. UPS, rather than autophagy, was responsible for the efficient Htt(Q74) degradation facilitated by MnFe2O4 NPs. Meanwhile, we demonstrated that MnFe2O4 NPs enhanced K48-linked ubiquitination of GFP-Htt(Q74). Moreover, ubiqinlin-1, but not p62/SQSTM1, served as the ubiquitin receptor that mediated the enhanced degradation of Htt(Q74) by MnFe2O4 NPs. Our findings may have implications for developing novel nanomedicine for the therapy of HD and other polyglutamine expansion diseases.

5.
Biomater Sci ; 7(3): 867-875, 2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30648710

RESUMO

As an active natural ingredient extracted from the plant Rheum palmatum, emodin exhibits various pharmacological activities, especially the inhibition of tumor growth and migration. However, the anticancer activity of emodin is limited mainly due to its poor solubility and the lack of specific targeting. Herein, we employed liposome to load emodin into the lipid bilayer, and high-performance ferromagnetic iron oxide nanocubes were simultaneously encapsulated in the hydrophilic bilayer. The optimized magnetic liposomal emodin nanocomposite (MLE) exhibited a 24.1% increase in the efficiency of killing MCF-7 cancer cells at a low concentration of 16 µg mL-1 compared with that of the hydrophobic free emodin. A further 8.67% enhancement of the killing efficiency was obtained by magnetic targeting. Benefitting from the high ferromagnetism, the transverse relaxivity (r2) of MLE was measured to be as high as 392.9 mM-1 s-1. With guidance from the external magnetic field, the effective accumulation of this magnetic liposome in the tumor region of a 4T1 breast tumor bearing mouse was observed by both MR tracking and fluorescence imaging, which should be beneficial for decreasing the required therapeutic dose of emodin. Hemolysis, cytotoxicity and biochemistry assays confirmed the excellent biocompatibility of this magnetic liposomal carrier. The anti-tumor therapeutic effect of MLE was further investigated in vivo, and the tumor in the therapeutic group was almost eliminated, indicating that this magnetic liposomal emodin could serve as a novel magnetically guided theranostic nanoagent.


Assuntos
Emodina/química , Lipossomos/química , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Emodina/uso terapêutico , Emodina/toxicidade , Feminino , Compostos Férricos/química , Hemólise/efeitos dos fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Células MCF-7 , Imagem por Ressonância Magnética , Magnetismo , Camundongos , Camundongos Endogâmicos BALB C , Nanocompostos/química , Nanocompostos/toxicidade , Transplante Heterólogo
6.
J Liposome Res ; 29(2): 133-141, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30022692

RESUMO

The purpose of this study was to optimize the preparation conditions of podophyllotoxin liposomes (PPT-Lips), and to investigate their effects on PC3 cells. PPT-Lips were prepared by using a thin-film dispersion method. In order to achieve maximum drug encapsulation efficiency (EE), the process and formulation variables were optimized by response surface methodology (RSM). The optimum preparation conditions were cholesterol to lecithin ratio of 3.6:40 (w/w), lipid to drug ratio of 15.8:1 (w/w), and the ultrasonic intensity of 35% (total power of 400 W). The experimental EE of PPT-Lips was 90.425%, which was consistent with the theoretically predicted value. The characterization studies showed that PPT-Lips were well-dispersible spherical particles with an average size of 106 nm and a zeta potential of -10.1 mV. A gradual and time-dependent pattern of PPT from liposomes was found in in vitro drug release with a cumulative release amount up to 70.3% in 24 h. Results of cell viability experiments on PC3 cells demonstrated that PPT-Lips exhibited more effective anticancer activity in comparison with free PPT. Therefore, PPT-Lips represent an efficient and promising drug delivery system for PPT.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Lipossomos/química , Nanopartículas/química , Podofilotoxina/farmacologia , Antineoplásicos Fitogênicos/administração & dosagem , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Colesterol/química , Cromatografia Líquida de Alta Pressão , Liberação Controlada de Fármacos , Humanos , Lecitinas/química , Masculino , Células PC-3 , Podofilotoxina/administração & dosagem
7.
PeerJ ; 6: e5369, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30065898

RESUMO

Cecropins, originally found in insects, are a group of cationic antimicrobial peptides. Most cecropins have an amphipathic N-terminal segment and a largely hydrophobic C-terminal segment, and normally form a helix-hinge-helix structure. In this study, we developed the novel 32-residue cecropin-like peptide cecropin DH by deleting the hinge region (Alanine-Glycine-Proline) of cecropin B isolated from Chinese oak silk moth, Antheraea pernyi. Cecropin DH possesses effective antibacterial activity, particularly against Gram-negative bacteria, with very low cytotoxicity against mammalian cells. Interactions between cecropin DH and the highly anionic lipopolysaccharide (LPS) component of the Gram-negative bacterial outer membrane indicate that it is capable of dissociating LPS micelles and disrupting LPS aggregates into smaller assemblies, which may play a vital role in its antimicrobial activity. Using LPS-stimulated mouse macrophage RAW264.7 cells, we found that cecropin DH exerted higher potential anti-inflammatory activity than cecropin B, as demonstrated by the inhibition of pro-inflammatory cytokines nitric oxide production and secretion of tumor necrosis factor-α. In conclusion, cecropin DH has potential as a therapeutic agent for both antibacterial and anti-inflammatory applications.

8.
Nat Commun ; 9(1): 2974, 2018 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-30061682

RESUMO

Biomimetic assembly of high-quality nanosheets into nacre-like structures can produce macroscopic films with favorable mechanical and optical performances due to the intrinsic properties and high level of ordering of the nanoscale building blocks. Natural ground mica is abundant and exhibits great application potential. However, large size and low aspect ratio greatly limit its biomimetic assembly. Moreover, exfoliation of ground mica into high-quality nanosheets remains a significant challenge. Here, we report that large-scale exfoliation of ground mica into mono- or few-layered mica nanosheets with a production rate of ~1.0 g h-1 can be successfully achieved. The mica nanosheets are then assembled into strong biomimetic polymeric mica film that inherits the high electric insulation, excellent visible transmittance, and unique ultraviolet-shielding properties of natural mica. Its overall performance is superior to that of natural sheet mica and other biomimetic films, making the polymeric mica film a suitable substrate for flexible and transparent devices.

9.
ACS Appl Mater Interfaces ; 10(37): 31044-31053, 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30148600

RESUMO

As a pharmaceutical excipient, dextran serves as an efficient ligand for stabilizing some clinically available inorganic nanomaterials such as iron oxide nanocrystals. Herein, dextran-capped nanosized europium(III) hydroxides [Eu(OH)3] nanoclusters (NCs) composed of 5 nm Eu(OH)3 nanoparticles have been large-scale synthesized via a microwave-accelerated hydrothermal reaction. The as-synthesized Eu(OH)3 NCs exhibited excellent physiological stability and biocompatibility both in vitro and in vivo and possessed considerable pro-proliferative activities in human umbilical vein endothelial cells (HUVECs). To investigate the epigenetic modulation of Eu(OH)3 NCs-elicited proliferation, the newly developed high-throughput next generation sequencing technology was employed herein. As a result, we have screened 371 dysregulated miRNAs in Eu(OH)3 NCs-treated HUVECs and obtained 26 potentially functional miRNAs in promoting cell proliferation. Furthermore, upregulated miR-199a-3p was predicted, validated, and eventually confirmed to be a crucial modulator in the pro-proliferative activity of Eu(OH)3 NCs by targeting zinc fingers and homeoboxes protein 1 (ZHX1). Importantly, these findings provide potential therapeutic strategy for ischemic heart/limb diseases and tissue regeneration by combination of nanomedicine and gene therapy with Eu(OH)3 NCs and miR-199a-3p-ZHX1 axis modulation.


Assuntos
MicroRNAs/metabolismo , Micro-Ondas , Nanopartículas/química , Proliferação de Células/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos
10.
Nanoscale ; 10(39): 18502-18509, 2018 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-29896584

RESUMO

Near infrared light (NIR) photodetectors based on one-dimensional semiconductor nanowires have generated considerable interest due to their practical application in versatile fields. We present a facile yet efficient approach to rationally integrating KCu7S4 semiconductor nanowires by the Langmuir-Blodgett (LB) technique. A self-powered near infrared (NIR) light photodetector is fabricated by transferring a close-packed KCu7S4 nanowire monolayer to the surface of a silicon wafer. The as-fabricated Si/KCu7S4 heterojunction with a close-packed and well-aligned nanowire array exhibits splendid photovoltaic performance when illuminated by NIR light, allowing the detection of NIR light without an exterior power supply. The photodetector exhibits a high sensitivity to NIR light (980 nm, 295.3 µW cm-2) with responsivity (R) 15 mA W-1 and detectivity (D*) 2.15 × 1012 cm Hz1/2 W-1. Significantly, the device shows the capability to work under high pulsed light irradiation up to 50 kHz with a high-speed response (response time τr 7.4 µs and recovery time τf 8.6 µs). This facilitates the fabrication of low-cost and high-speed photodetectors and integrated optoelectronic sensor circuitry.

11.
Biomater Sci ; 5(12): 2403-2415, 2017 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-29072715

RESUMO

It is a significant challenge to develop nanoscale magnetic resonance imaging (MRI) contrast agents with high performance of relaxation. In this work, Gd3+-doped CaF2-based core-shell nanoparticles (CaF2:Yb,Er@CaF2:Gd) of sub-10 nm size were controllably synthesized by a facile sequential growth method. The as-prepared hydrophilic CaF2:Yb,Er@CaF2:Gd nanoparticles modified using PEG-PAA di-block copolymer benefited from the presence of Gd only in the outer CaF2 layer of the nanoparticles, which exhibited r1 as high as 21.86 mM-1 s-1 under 3.0 T, seven times as high as that of commercially used gadopentetate dimeglumine (Gd-DTPA). Low cytotoxicity, no hemolysis phenomenon and no potential gadolinium ion leakage phenomenon of the hydrophilic CaF2:Yb,Er@CaF2:Gd nanoparticles have been observed and confirmed. Clear vascular details can be observed in magnetic resonance angiography and obvious MR signal of 4T1 tumor area could be significantly improved by intravenous injection of the hydrophilic CaF2:Yb,Er@CaF2:Gd nanoparticles at a low dosage in mice. A series of in vivo biological safety evaluations confirmed the good biocompatibility of the hydrophilic CaF2:Yb,Er@CaF2:Gd nanoparticles, which might be employed in clinical blood pool imaging and tumor diagnosis as a safe and efficient MRI probe.


Assuntos
Angiografia por Ressonância Magnética/métodos , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Neoplasias/diagnóstico , Animais , Meios de Contraste/química , Meios de Contraste/uso terapêutico , Gadolínio/química , Gadolínio/uso terapêutico , Células HeLa , Humanos , Imagem por Ressonância Magnética/métodos , Camundongos , Nanopartículas/uso terapêutico , Neoplasias/patologia , Itérbio/química , Itérbio/uso terapêutico
12.
Sci Rep ; 7(1): 13851, 2017 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-29062048

RESUMO

With the emerging of drug-resistant bacterial and fungal pathogens, there raise the interest of utilizing versatile antimicrobial biomaterials to treat the acute wound. Herein, we report the spraying mediated assembly of a bio-inspired Ag@reduced graphene-sodium alginate (AGSA) composite film for effective wound healing. The obtained film displayed lamellar microstructures similar to the typical "brick-and-mortar" structure in nacre. In this nacre-mimic structure, there are abundant interfacial interactions between nanosheets and polymeric matrix, leading to remarkable reinforcement. As a result, the tensile strength, toughness and Young's modulus have been improved 2.8, 2.3 and 2.7 times compared with pure sodium alginate film, respectively. In the wound healing study, the AGSA film showed effective antimicrobial activities towards Pseudomonas aeruginosa, Escherichia coli and Candida albicans, demonstrating the ability of protecting wound from pathogenic microbial infections. Furthermore, in vivo experiments on rats suggested the effect of AGSA film in promoting the recovery of wound sites. According to MTT assays, heamolysis evaluation and in vivo toxicity assessment, the composite film could be applied as a bio-compatible material in vitro and in vivo. Results from this work indicated such AGSA film has promising performance for wound healing and suggested great potential for nacre-mimic biomaterials in tissue engineering applications.


Assuntos
Alginatos/química , Proliferação de Células , Grafite/química , Nácar/administração & dosagem , Óxidos/química , Prata/química , Compostos de Sódio/química , Cicatrização , Animais , Biomimética , Módulo de Elasticidade , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Teste de Materiais , Nácar/química , Ratos , Ratos Sprague-Dawley , Resistência à Tração
13.
J Biol Chem ; 292(40): 16571-16577, 2017 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-28808052

RESUMO

Mavacamten, formerly known as MYK-461 is a recently discovered novel small-molecule modulator of cardiac myosin that targets the underlying sarcomere hypercontractility of hypertrophic cardiomyopathy, one of the most prevalent heritable cardiovascular disorders. Studies on isolated cells and muscle fibers as well as intact animals have shown that mavacamten inhibits sarcomere force production, thereby reducing cardiac contractility. Initial mechanistic studies have suggested that mavacamten primarily reduces the steady-state ATPase activity by inhibiting the rate of phosphate release of ß-cardiac myosin-S1, but the molecular mechanism of action of mavacamten has not been described. Here we used steady-state and presteady-state kinetic analyses to investigate the mechanism of action of mavacamten. Transient kinetic analyses revealed that mavacamten modulates multiple steps of the myosin chemomechanical cycle. In addition to decreasing the rate-limiting step of the cycle (phosphate release), mavacamten reduced the number of myosin-S1 heads that can interact with the actin thin filament during transition from the weakly to the strongly bound state without affecting the intrinsic rate. Mavacamten also decreased the rate of myosin binding to actin in the ADP-bound state and the ADP-release rate from myosin-S1 alone. We, therefore, conclude that mavacamten acts on multiple stages of the myosin chemomechanical cycle. Although the primary mechanism of mavacamten-mediated inhibition of cardiac myosin is the decrease of phosphate release from ß-cardiac myosin-S1, a secondary mechanism decreases the number of actin-binding heads transitioning from the weakly to the strongly bound state, which occurs before phosphate release and may provide an additional method to modulate myosin function.


Assuntos
Difosfato de Adenosina/química , Trifosfato de Adenosina/química , Benzilaminas/química , Miosinas Cardíacas/química , Subfragmentos de Miosina/química , Sarcômeros/química , Uracila/análogos & derivados , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Miosinas Cardíacas/metabolismo , Cardiomegalia/metabolismo , Bovinos , Subfragmentos de Miosina/metabolismo , Sarcômeros/metabolismo , Uracila/química
14.
J Biomed Nanotechnol ; 13(11): 1435-1445, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31271130

RESUMO

As a phenyltetralin-type lignin isolated from roots and rhizomes of Podophyllum hexandrum, podophyllotoxin (POD) possesses a great deal of biological activities, especially the anticancer activity via preventing the division of cancerous cells. However, its practical clinical application as an anticancer agent is hindered by its poor water solubility and serious side effects. Herein, we enclosed the POD into the hydrophobic cavity of natural phosphatidylcholine based liposomes to improve its solubility and thus, enhance the chemotherapeutic effect. Modified gold nanorods (GNRs) were further conjugated onto the liposomal POD composite (GLP) for enhanced photothermal stability. The extinction coefficient of GLP aqueous dispersion at 808 nm was calculated to be 8.08 Lg-1 cm-1, and the photothermal conversion efficiency was calculated to be 46.1%. In addition, the release of POD from GLP composite was effectively triggered by NIR irradiation. Compared with the cellular viabilities in the single chemotherapy group (54.6%) and the single photothermal therapy group (66.9%), only 10.3% 4T1 cells were survived after photothermal and chemotherapy simultaneously in the GLP group after exposure to 808 nm NIR laser at an intensity of 1.0 W/cm² for 5 min. The cytotoxicity and hemolysis assay further demonstrated the excellent biocompatibility of POD based liposomal composite. Overall, the GNRs conjugated liposomal POD is a promising therapeutic nanoagent for synergistic chemo-thermal therapy.

15.
PLoS Negl Trop Dis ; 10(10): e0005076, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27760141

RESUMO

OBJECTIVE: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging hemorrhagic fever caused by a tick-borne bunyavirus (SFTSV) in East Asian countries. The role of human leukocyte antigen (HLA) in resistance and susceptibility to SFTSV is not known. We investigated the correlation of HLA locus A, B and DRB1 alleles with the occurrence of SFTS. METHODS: A total of 84 confirmed SFTS patients (patient group) and 501 unrelated non-SFTS patients (healthy individuals as control group) from Shandong Province were genotyped by PCR-sequence specific oligonucleotide probe (PCR-SSOP) for HLA-A, B and DRB1 loci.Allele frequency was calculated and compared using χ2 test or the Fisher's exact test. A corrected P value was calculated with a bonferronis correction. Odds Ratio (OR) and 95% confidence intervals (CI) were calculated by Woolf's method. RESULTS: A total of 11 HLA-A, 23 HLA-B and 12 HLA-DRB1 alleles were identified in the patient group, whereas 15 HLA-A, 30 HLA-B and 13 HLA-DRB1 alleles were detected in the control group. The frequencies of A*30 and B*13 in the SFTS patient group were lower than that in the control group (P = 0.0341 and 0.0085, Pc = 0.5115 and 0.252). The ORs of A*30 and B*13 in the SFTS patient group were 0.54 and 0.49, respectively. The frequency of two-locus haplotype A*30-B*13 was lower in the patient group than in the control group(5.59% versus 12.27%, P = 0.037,OR = 0.41, 95%CI = 0.18-0.96) without significance(Pc>0.05). A*30-B*13-DRB1*07 and A*02-B*15-DRB1*04 had strong associations with SFTS resistance and susceptibility respectively (Pc = 0.0412 and 0.0001,OR = 0.43 and 5.07). CONCLUSION: The host HLA class I polymorphism might play an important role with the occurrence of SFTS. Negative associations were observed with HLA-A*30, HLA-B*13 and Haplotype A*30-B*13, although the associations were not statistically significant. A*30-B*13-DRB1*07 had negative correlation with the occurrence of SFTS; in contrast, haplotype A*02-B*15-DRB1*04 was positively correlated with SFTS.


Assuntos
Infecções por Bunyaviridae/genética , Frequência do Gene , Predisposição Genética para Doença , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Cadeias HLA-DRB1/genética , Phlebovirus , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções por Bunyaviridae/sangue , Infecções por Bunyaviridae/virologia , Feminino , Genótipo , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Phlebovirus/isolamento & purificação , Reação em Cadeia da Polimerase , Polimorfismo Genético
16.
Science ; 351(6273): 617-21, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26912705

RESUMO

Hypertrophic cardiomyopathy (HCM) is an inherited disease of heart muscle that can be caused by mutations in sarcomere proteins. Clinical diagnosis depends on an abnormal thickening of the heart, but the earliest signs of disease are hyperdynamic contraction and impaired relaxation. Whereas some in vitro studies of power generation by mutant and wild-type sarcomere proteins are consistent with mutant sarcomeres exhibiting enhanced contractile power, others are not. We identified a small molecule, MYK-461, that reduces contractility by decreasing the adenosine triphosphatase activity of the cardiac myosin heavy chain. Here we demonstrate that early, chronic administration of MYK-461 suppresses the development of ventricular hypertrophy, cardiomyocyte disarray, and myocardial fibrosis and attenuates hypertrophic and profibrotic gene expression in mice harboring heterozygous human mutations in the myosin heavy chain. These data indicate that hyperdynamic contraction is essential for HCM pathobiology and that inhibitors of sarcomere contraction may be a valuable therapeutic approach for HCM.


Assuntos
Adenosina Trifosfatases/antagonistas & inibidores , Benzilaminas/administração & dosagem , Miosinas Cardíacas/antagonistas & inibidores , Cardiomiopatia Hipertrófica Familiar/tratamento farmacológico , Contração Miocárdica/efeitos dos fármacos , Cadeias Pesadas de Miosina/antagonistas & inibidores , Sarcômeros/efeitos dos fármacos , Uracila/análogos & derivados , Animais , Benzilaminas/química , Miosinas Cardíacas/genética , Cardiomiopatia Hipertrófica Familiar/patologia , Cardiomiopatia Hipertrófica Familiar/fisiopatologia , Células Cultivadas , Modelos Animais de Doenças , Fibrose , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/patologia , Heterozigoto , Humanos , Masculino , Camundongos , Camundongos Endogâmicos , Mutação , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Cadeias Pesadas de Miosina/genética , Ratos , Uracila/administração & dosagem , Uracila/química
17.
Protein Expr Purif ; 116: 98-104, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26297993

RESUMO

Design of experiment (DoE) is a statistics-based technique for experimental design that could overcome the shortcomings of traditional one-factor-at-a-time (OFAT) approach for protein purification optimization. In this study, a DoE approach was applied for optimizing purification of a recombinant single-chain variable fragment (scFv) against type 1 insulin-like growth factor receptor (IGF-1R) expressed in Escherichia coli. In first capture step using Capto L, a 2-level fractional factorial analysis and successively a central composite circumscribed (CCC) design were used to identify the optimal elution conditions. Two main effects, pH and trehalose, were identified, and high recovery (above 95%) and low aggregates ratio (below 10%) were achieved at the pH range from 2.9 to 3.0 with 32-35% (w/v) trehalose added. In the second step using cation exchange chromatography, an initial screening of media and elution pH and a following CCC design were performed, whereby the optimal selectivity of the scFv was obtained on Capto S at pH near 6.0, and the optimal conditions for fulfilling high DBC and purity were identified as pH range of 5.9-6.1 and loading conductivity range of 5-12.5 mS/cm. Upon a further gel filtration, the final purified scFv with a purity of 98% was obtained. Finally, the optimized conditions were verified by a 20-fold scale-up experiment. The purities and yields of intermediate and final products all fell within the regions predicted by DoE approach, suggesting the robustness of the optimized conditions. We proposed that the DoE approach described here is also applicable in production of other recombinant antibody constructs.


Assuntos
Receptor IGF Tipo 1/imunologia , Anticorpos de Cadeia Única/imunologia , Anticorpos de Cadeia Única/isolamento & purificação , Cromatografia de Afinidade/métodos , Cromatografia por Troca Iônica/métodos , Clonagem Molecular/métodos , Escherichia coli/genética , Humanos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Projetos de Pesquisa , Anticorpos de Cadeia Única/química , Anticorpos de Cadeia Única/genética , Solubilidade
18.
Transfus Apher Sci ; 51(1): 58-64, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25129827

RESUMO

BACKGROUND: In China apheresis platelets (PLTs) are stored in plasma for only 5 days, resulting in PLT inventory pressures. Anandamide (ANA) was reported to be a potential agent to inhibit PLT apoptosis. The aim of this study was to evaluate the characteristics of extended storage PLTs in plasma treated with ANA in vitro. METHODS: Apheresis PLTs (n = 20) were prepared in plasma treated with ANA, and stored at 22 °C for up to 11 days. On day 1, 3, 5, 7, 9 and 11, PLTs were tested for PLT count, mean PLT volume (MPV), PLT distribution width (PDW), pH, pCO(2), pO(2), hypotonic shock response (HSR), phosphatidylserine (PS) exposure and soluble P-selectin content. RESULTS: PLTs stored in plasma with/without ANA didn't show significant differences during the first 5 days of storage. From the 7(th) day on, PLTs stored in plasma with ANA displayed significantly lower PS expression, soluble P-selectin content and higher HSR scores than those stored in plasma without ANA (P <0.05), respectively. CONCLUSION: The extended storage of PLTs in plasma treated with 0.5 µmol/l ANA showed better characteristics of the PLTs, compared with the control group, which was suggested to potentially alleviate the PLT storage lesion.


Assuntos
Ácidos Araquidônicos/farmacologia , Plaquetas/metabolismo , Preservação de Sangue/métodos , Bloqueadores dos Canais de Cálcio/farmacologia , Endocanabinoides/farmacologia , Plasma , Plaquetoferese , Alcamidas Poli-Insaturadas/farmacologia , Feminino , Humanos , Masculino , Fatores de Tempo
19.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 31(4): 518-21, 2014 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25119926

RESUMO

OBJECTIVE: To confirm 17 rare HLA alleles detected during routine HLA typing and deduce their haplotypes. METHODS: Bi-allelic sequence-based typing and Luminex DNA PCR-SSOP assay were applied for the initial or repeat HLA typing, respectively. The rare HLA alleles were confirmed with mono-allelic sequence-based typing. Predicted haplotypes of the rare alleles were inferred based on the frequencies of HLA alleles and haplotypes in Han population. RESULTS: The authenticity of the total 17 rare HLA alleles was proven, and 18 predicted haplotypes associated with the rare alleles were recognized. A*11:12 and DRB1*13:19 were detected twice among unrelated individuals. CONCLUSION: Study of rare HLA alleles and predicted haplotype can provide useful information for donor searching and transplantation, and enrich polymorphisms of HLA in this population.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Cadeias HLA-DRB1/genética , Alelos , Grupo com Ancestrais do Continente Asiático/etnologia , Frequência do Gene , Haplótipos , Humanos
20.
Tumour Biol ; 35(9): 8893-901, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24894673

RESUMO

Hepatocellular carcinomas are an aggressive malignancy mainly due to metastasis or postsurgical recurrence. Expression of E-cadherin is strongly reduced in Hepatocellular carcinoma (HCC) tissues, and its downregulation is connected to invasiveness and metastasis in hepatocellular carcinomas. The previous study showed that the supernatant from activated macrophages can downregulate the expression of E-cadherin in HCC cells. The partial known molecular mechanism is that tyrosine kinases c-Src- and EGFR phosphorylate ß-catenin and E-cadherin leading to destabilization of E-cadherin/ß-catenin complex. The aim of this study is to clarify other mechanism by which activated macrophages downregulate the expression of E-cadherin. We detect the expression of E-cadherin and macrophage infiltration in hepatocellular carcinoma tissues by double-staining immunohistochemistry and evaluate the relationship between macrophages and E-cadherin expression in hepatocellular carcinoma cells in vitro experiments. We found that reduced expression of E-cadherin was associated with macrophage infiltration along the border between the tumor nest and stroma in hepatocellular carcinoma tissues. Besides, protein expression of E-cadherin was significantly decreased in hepatocellular carcinoma cells co-cultured with macrophages derived from THP-1 cells. Consistently, mRNA expression of E-cadherin was also decreased in cancer cells co-cultured with THP-1-differentiated macrophages. Moreover, the downregulation of E-cadherin expression was companied by upregulation of Slug expression in cancer cells with conditional medium from THP-1-differentiated macrophage culture. The change in expression of E-cadherin and Slug was abrogated when NF-κB signaling pathway was blocked. All the findings suggested that macrophages contributed to the decreased expression of E-cadherin by NF-κB/Slug pathway in hepatocellular carcinomas.


Assuntos
Caderinas/biossíntese , Macrófagos/metabolismo , NF-kappa B/metabolismo , Fatores de Transcrição/metabolismo , Animais , Western Blotting , Caderinas/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Células Cultivadas , Técnicas de Cocultura , Regulação para Baixo , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Ativação de Macrófagos , Macrófagos/imunologia , NF-kappa B/genética , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Fatores de Transcrição da Família Snail , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Fatores de Transcrição/genética
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