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1.
J Mol Cell Cardiol ; 179: 7-17, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36977444

RESUMO

Single-cell approaches have become an increasingly popular way of understanding the genetic factors behind disease. Isolation of DNA and RNA from human tissues is necessary to analyze multi-omic data sets, providing information on the single-cell genome, transcriptome, and epigenome. Here, we isolated high-quality single-nuclei from postmortem human heart tissues for DNA and RNA analysis. Postmortem human tissues were obtained from 106 individuals, 33 with a history of myocardial disease, diabetes, or smoking, and 73 controls without heart disease. We demonstrated that the Qiagen EZ1 instrument and kit consistently isolated genomic DNA of high yield, which can be used for checking DNA quality before conducting single-cell experiments. Here, we provide a method for single-nuclei isolation from cardiac tissue, otherwise known as the SoNIC method, which allows for the isolation of single cardiomyocyte nuclei from postmortem tissue by nuclear ploidy status. We also provide a detailed quality control measure for single-nuclei whole genome amplification and a pre-amplification method for confirming genomic integrity.


Assuntos
Núcleo Celular , Miocárdio , Humanos , Núcleo Celular/genética , Miócitos Cardíacos , DNA , RNA/genética , Análise de Célula Única/métodos
2.
bioRxiv ; 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36778433

RESUMO

Single-cell approaches have become an increasingly popular way of understanding the genetic factors behind disease. Isolation of DNA and RNA from human tissues is necessary to analyze multi-omic data sets, providing information on the single-cell genome, transcriptome, and epigenome. Here, we isolated high-quality single-nuclei from postmortem human heart tissues for DNA and RNA analysis. Postmortem human tissues were obtained from 106 individuals, 33 with a history of myocardial disease, diabetes, or smoking, and 73 controls without heart disease. We demonstrated that the Qiagen EZ1 instrument and kit consistently isolated genomic DNA of high yield, which can be used for checking DNA quality before conducting single-cell experiments. Here, we provide a method for single-nuclei isolation from cardiac tissue, otherwise known as the SoNIC method, which allows for the isolation of single cardiomyocyte nuclei from postmortem tissue by nuclear ploidy status. We also provide a detailed quality control measure for single-nuclei whole genome amplification and a pre-amplification method for confirming genomic integrity.

3.
PLoS One ; 17(5): e0268019, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35507605

RESUMO

It is puzzling how altruistic punishment of defectors can evolve in large groups of nonrelatives, since punishers should voluntarily bear individual costs of punishing to benefit those who do not pay the costs. Although two distinct mechanisms have been proposed to explain the puzzle, namely voluntary participation and group-level competition and selection, insights into their joint effects have been less clear. Here we investigated what could be combined effects of these two mechanisms on the evolution of altruistic punishment and how these effects can vary with nonparticipants' individual payoff and group size. We modelled altruistic punishers as those who contribute to a public good and impose a fine on each defector, i.e., they are neither pure punishers nor excluders. Our simulation results show that voluntary participation has negative effects on the evolution of cooperation in small groups regardless of nonparticipants' payoffs, while in large groups it has positive effects within only a limited range of nonparticipants' payoff. We discuss that such asymmetric effects could be explained by evolutionary forces emerging from voluntary participation. Lastly, we suggest that insights from social science disciplines studying the exit option could enrich voluntary participation models.


Assuntos
Teoria dos Jogos , Punição , Altruísmo , Evolução Biológica , Comportamento Cooperativo , Processos Grupais
4.
J Tradit Complement Med ; 10(3): 198-206, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32670814

RESUMO

Korean Red Ginseng (KRG) exerts chemopreventive effects on experimentally induced carcinogenesis through multiple mechanisms. In this study, we investigated effects of KRG on dextran sulfate sodium (DSS)-induced colitis and azoxymethane (AOM) plus DSS-induced colon carcinogenesis in mice. Male C57BL/6J mice were fed diet containing 1% KRG or a standard diet throughout the experiment. The mouse colitis was induced by administration of 3% DSS in drinking water for 1 week. DSS caused body weight loss, diarrhea, rectal bleeding and colon length shortening, and all these symptoms were ameliorated by KRG treatment. KRG inhibited DSS-induced expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) by suppressing activation of nuclear factor-kappa B (NF-κB) and signal transducer and activation of transcription 3 (STAT3). In another experiment, colon carcinogenesis was initiated by single intraperitoneal injection of AOM (10 mg/kg) and promoted by 2% DSS in drinking water. KRG administration relieved the symptoms of colitis and reduced the incidence, the multiplicity and the size of colon tumor. The up-regulation of COX-2, iNOS, c-Myc and Cyclin D1 by AOM plus DSS was attenuated in KRG fed mice which was associated with suppression of NF-κB and STAT3 activation. These results suggest that KRG is a potential candidate for chemoprevention of inflammation-associated cancer in the colon.

5.
Nanoscale ; 12(15): 8216-8229, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32118238

RESUMO

To understand the relationship between the work function and structural properties of sufficiently expanded triangular defects (size: ∼250 µm) in the 4H-SiC epitaxial layer, Kelvin probe force microscopy (KPFM) and spectroscopic [micro-Raman spectroscopy and photoluminescence (PL)] analyses were performed. Spectroscopic analysis demonstrated that the triangular defects mostly comprise the 3C polytypes and that it experiences internal stress, defects, and defect-induced carrier generation. The distinguishable areas in the triangular defects had surface potential values different from those of the 4H-SiC matrix; this could be explained by the work function difference, which arises from variations in the electron affinity of the 3C polytype as well as the positional variations of the Fermi energy level in terms of electron concentration. In addition, tensile-stress-induced surface disorder leading to variations in electron affinity was discussed. The mechanical properties of the triangular defects measured by a nanoindenter were significantly deteriorated because of many dislocation arrays and stacking faults with many broken and/or strained bonds.

6.
J Nanosci Nanotechnol ; 20(8): 4657-4660, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32126636

RESUMO

An isomeric series of phosphine oxides with N-phenyl benzimidazole such as 2-DPPI, 3-DPPI and 4-DPPI were synthesized for organic light emitting diodes (OLED). The thermal properties of DPPI isomers were determined by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). OLED devices using DPPI isomers as the emitting material were fabricated, which configuration was ITO/MoOx [30 nm]/NPB [500 nm]/DPPI [300 nm]/Alq3 [200 nm]/Liq[10 nm]/Al [120 nm]. The emitting colors of the devices were respectively a deep-blue (430 nm, 4-DPPI) and greenish-yellows (510-580 nm, 3-DPPI and 530 nm, 2-DPPI). In particular, the emitting color of 4-DPPI device was not changed during the alteration of applied voltages (6.5-11.5 V), and the CIE coordinate was a satisfactory deep-blue (0.161, 0.101).

7.
J Nanosci Nanotechnol ; 20(8): 5107-5111, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32126707

RESUMO

Additive manufacturing or three-dimensional (3D) printing is considered a disruptive technology for producing components with topologically optimized complex geometries as well as functionalities that are not achievable by traditional methods. 3D printing is expected to revolutionize the manufacturing of components. While several 3D printing systems are available, printing based on fused-deposition modeling (FDM) using thermoplastics is particularly widespread because of the simplicity and potential applicability of the method. In this study, we report the analysis of correlation between contrast and component of polylactic acid (PLA) based composite for FDM 3D printing. The pre-fabricated white composite and black composite were mixed in the fraction of 100:0, 90:10, 75:25, 50:50, 25:75, and 0:100% (v/v) and the obtained mixture was extruded using HX-35 3D filament extrusion line. The samples in different contrast were printed in disk like shape, and the gray scale filaments and 3D printed samples were measured the morphology and components using a field emission scanning electron microscope and energy dispersive X-ray spectroscopy. The CIE-lab values of the samples were measured using a colorimeter and the correlation between CIE-lab values and the components were analyzed. Although the component of Ti was linearly increased, the CIE-lab values show a clear exponential increase by increasing the white composite.

8.
J Nanosci Nanotechnol ; 19(8): 4791-4794, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30913789

RESUMO

Amyloid ß (Aß) peptide is secreted from the outside of neural cell by a neural signal pathway and it accumulated each other results in the highly toxicity amyloid plaque which is a critical causative factor in the pathogenesis of Alzheimer's Disease (AD). The peptide is considered to be a potential biomarker to diagnose AD. Here we introduce a novel poly-L-lysine (PLL) mediated nanobiosensor to detect Aß in vitro. The PLL molecules were utilized as a signal amplifier of Aß detection. The indirect enzyme-linked immunosorbent assay (ELISA) method and the sandwich ELISA method have tried to the detection of Aß. A commercially available ELISA plate was modified by PLL using a chemical agent and the amplified amino groups were activated by a functional group for the binding of Aß. The bound Aß was further modified with a primary antibody and fluorescence molecules conjugated secondary antibody by the traditional immunochemistry. In the result, the fluorescence intensity was increased by the increasing concentration of Aß, and the best Aß detection results were obtained in the PLL mediated indirect ELISA nanobiosensor. We expected that the present method would be optimized and applied for the detection of Aß in human fluid.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Técnicas Biossensoriais , Ensaio de Imunoadsorção Enzimática , Humanos , Nanotecnologia , Fragmentos de Peptídeos , Placa Amiloide , Polilisina
9.
J Nanosci Nanotechnol ; 19(3): 1786-1789, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30469267

RESUMO

Amyloid ß (Aß) is considered to be one of a potential biomarker to monitor Alzheimer's Disease (AD) not only for diagnostic purposes but for early detection. Here we describe a novel nano-biosensor for Aß mediated by poly-L-lysine (PLL) which was used for the amplification of detection signal for Aß. The indirect enzyme-linked immunosorbent assay (ELISA) method was modified using PLL for the amplification of the Aß detection signal. A commercially available ELISA plate was modified by PLL using chemical agent and the amplified amino groups were activated by a chemical agent for the detection of Aß. The detection was carried out by the traditional immunochemistry using primary antibody and fluorescence molecules conjugated secondary antibody. In the result, the fluorescence intensity was increased by the increasing treated Aß amount, and the sensitivity was approximately 2 times higher in the concentration of 2 ng/mL Aß treatment, and approximately 4 times higher in the concentration of 200 ng/mL Aß treatment compare with that of indirect ELISA detection method. We suggest our novel signal amplification method for the Aß early detection.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Ensaio de Imunoadsorção Enzimática , Humanos , Fragmentos de Peptídeos , Polilisina
10.
Sensors (Basel) ; 18(8)2018 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-30126145

RESUMO

We propose a dual-channel interface architecture that allocates high and low transition-density bit streams to two separate channels. The transmitter utilizes the stacked drivers with charge-recycling to reduce the power consumption. The direct current (DC)-coupled receiver front-end circuits manage the common-mode level variations and compensate for the channel loss. The tracked oversampling clock and data recovery (CDR), which realizes fast lock acquisition below 1 baud period and low logic latency, is shared by the two channels. Fabricated in a 65-nm low-power complementary metal-oxide semiconductor (CMOS) technology, the dual-channel transceiver achieves 12-Gb/s data rate while the transmitter consumes 20.43 mW from a 1.2-V power supply.

11.
J Nanosci Nanotechnol ; 18(10): 7120-7123, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29954544

RESUMO

Actin filament senses mechanical forces and it is transduced into biochemical signals during many cellular processes. In the disassembling process of actin filaments, cofilin plays a central role as the actin filament depolymerization. In this study, we evaluated a quantitative analysis of the actin filament-cofilin interaction change dependent upon the actin filament curvature decrease using atomic force microscopy (AFM) and a fabricated wave-like substrate. A wave-like substrate was fabricated by a maskless photo-lithography of a spin coated film on a glass substrate, and graphene oxide sheet was used for the decreasing of non-specific interaction between protein and the substrate. By single-molecule force spectroscopy, we determined rupture force of actin filament-cofilin binding on the wave-like substrate and a flat substrate. The rupture force of actin filament-cofilin binding at the curvature of -1.35 µm-1 showed a value approximately 4 times higher than the rupture force at the curvature of -0.15 µm-1. The present study will provide the possibility and quantitative evidence that mechanical stress on cytoskeletal filaments can modulate how they interact with their binding proteins.

12.
J Nanosci Nanotechnol ; 18(2): 1410-1413, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448601

RESUMO

Amyloid ß (Aß) peptide is considered to be the critical causative factor in the pathogenesis of Alzheimer's disease (AD) because the hydrophilic molecules accumulated outside of the neural cells and results in the formation of highly toxicity amyloid plaque. In this study, we probed the interaction between Aß and the antibody using atomic force microscopy (AFM). We compared two kinds of antibodies which are the antibody for Aß 1-42 (antibody42) and the antibody for Aß 1-16 (antibody16). To detect the interaction between Aß and the antibodies, the single molecular force spectroscopy was carried out using Aß modified glass substrate and the antibodies modified AFM probes. In the results, the single Aß-antibody42 dissociation constant was estimated to be 5.2 × 10-3 s-1 and the single Aß-antibody16 dissociation constant was 2.8×10-2 s-1. The Aß-antibody42 showed 5.3 times longer bond life time compare with Aß-antibody16. It suggested that antibody42 is better choice for the Aß sensor development.


Assuntos
Peptídeos beta-Amiloides/análise , Anticorpos/imunologia , Microscopia de Força Atômica , Fragmentos de Peptídeos/análise , Doença de Alzheimer/imunologia , Amiloide , Peptídeos beta-Amiloides/imunologia , Humanos , Placa Amiloide
13.
Opt Express ; 26(26): 34142-34149, 2018 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-30650842

RESUMO

Virtual reality-head mounted displays require a display with high resolution over 2000 ppi, super-fast response time and high contrast ratio for realizing super image quality at near-eyes. Several liquid crystal devices utilizing fringe-field switching (FFS) mode, having response times less than of half of conventional FFS mode, were proposed for this purpose. However, its contrast ratio is still less than 2000:1 because of intrinsic electro-optic characteristics of homogenous alignment mode and also realizing high resolution like 2000 ppi has some difficulty because twist deformation of liquid crystals can easily affect liquid crystal orientation near pixels. In this paper, we propose a vertically aligned liquid crystal device in which bend deformation occurs in a confined area by an oblique electric field, exhibiting 4 times faster decay response time than that of conventional FFS mode, higher contrast ratio over 5000:1, and pixel pitch less than 4 µm. The proposed liquid crystal device has a strong potential to be the main display for high-resolution virtual reality over 2000 ppi.

14.
Proc Natl Acad Sci U S A ; 114(5): 921-925, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-28096383

RESUMO

Smallholder agricultural systems, strongly dependent on water resources and investments in shared infrastructure, make a significant contribution to food security in developing countries. These communities are being increasingly integrated into the global economy and are exposed to new global climate-related risks that may affect their willingness to cooperate in community-level collective action problems. We performed field experiments on public goods with private and collective risks in 118 small-scale rice-producing communities in four countries. Our results indicate that increasing the integration of those communities with the broader economic system is associated with lower investments in public goods when facing collective risks. These findings indicate that local public good provision may be negatively affected by collective risks, especially in communities more integrated with the market economy.


Assuntos
Agricultura , Participação da Comunidade , Abastecimento de Alimentos , Adulto , China , Mudança Climática , Colômbia , Humanos , Nepal , Oryza , Risco , Tailândia
15.
Clin Imaging ; 40(6): 1156-1161, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27568071

RESUMO

The purpose of this work was to evaluate cases of benign ovarian mature teratoma (MT) with enhancing solid components on pelvic magnetic resonance imaging (MRI) and to correlate the MRI findings with the pathology reports. We retrospectively reviewed MRI findings and pathologic reports of 126 patients with pathologically confirmed ovarian MT. Enhancing solid components were observed in 24 (18.8%) of 128 benign MTs. The largest diameter ranged from 5.9 to 42.2 mm. The appearance was variable. Of 24 tumors, 19 (79.2%) had regular borders. On pathologic analysis, solid components of benign MTs were identified as glial tissue, thyroid tissue, fibrous stroma, or vessels.


Assuntos
Neoplasias Ovarianas/patologia , Teratoma/patologia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neoplasias Embrionárias de Células Germinativas/diagnóstico por imagem , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Ovarianas/diagnóstico por imagem , Estudos Retrospectivos , Teratoma/diagnóstico por imagem , Adulto Jovem
16.
J Nanosci Nanotechnol ; 16(6): 6322-6, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27427711

RESUMO

In this study, for the development of future molecular electronic devices, we have investigated the characteristics of the aggregates of Langmuir-Blodgett films. The characteristics of intramolecular charge transfer by J-aggregates in merocyanine dye LB films have been studied experimentally by using UV irradiation and heat treatment. In addition to intramolecular charge transfer, we also studied the conjugation and energy changes of the molecules. In case a dye is thinned by LB method, the alkyl chain is often displaced in order to form a mono-molecular film with ease. Since the molecular association form is often made by self-organization of molecules themselves, in case the dye and the alkyl chain are strongly bonded by the covalent bond, it may be said that the properties of the LB film to be built up are almost determined at the time of synthesis of film-forming molecules. Meanwhile, since, in case LB film is fabricated by the diffusion absorption method, the cohesive force between the water-soluble dye and the surface-active mono-molecular film is electrostatic, the dye molecule can move relatively freely on the air/water interface, which may be regarded as a two-dimensional crystal growth process.

17.
J Nanosci Nanotechnol ; 16(6): 6374-7, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27427721

RESUMO

We synthesized the red emission material, bis(1,4-bis(5-phenyloxazol-2-yl)phenyl) iridium(picolate) [Ir-complexes] and the blue emission material, bis (2-(2-hydroxyphenyl) benzoxazolate)zinc [Zn(HPB)2]. White Organic Light Emitting Diodes were fabricated by using Zn(HPB)2 for a blue emitting layer, Ir-complexes for a red emitting layer and a tris (8-hydroxy quinoline)aluminum [Alq3] for a green emitting layer. The important experimental results obtained, white OLED was fabricated by using double emitting layers of Zn(HPB)2 and Alq3:Ir-complexes, and hole blocking layer of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline[BCP]. We also varied the thickness of BCP. When the thickness of BCP layer was 5 nm, white emission was achieved. We obtained a maximum luminance of 5400 cd/m2 at a current density of 650 mA/cm2. The CIE coordinates was (0.339, 0.323) at voltage of 10 V.

18.
J Nanosci Nanotechnol ; 16(6): 6388-92, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27427724

RESUMO

To understand the structural stability of as-prepared octanethiol (OT) self-assembled monolayers (SAMs) with a fully covered c(4 x 2) phase on Au(111) in ultrahigh vacuum (UHV) conditions of 3 x 10(-7) Pa at room temperature, we examined OT SAM samples obtained as a function of storage period using scanning tunneling microscopy (STM). STM imaging revealed that phase transition of OT SAMs after storage in UHV for 3 days occurs from the c(4 x 2) phase to the mixed phase containing ordered c(4 x 2) and disordered phases. It was also observed that the disordered phase was mainly located at around vacancy islands and near step edges of Au(111) terraces, implying that desorption of OT molecules chemisorbed on Au(111) in UHV occurs more quickly in these regions compared with in the closely packed and ordered domains. After a longer storage in UHV for 6 days, OT SAMs with the c(4 x 2) phase were changed to the disordered phase containing a partially ordered domain with a row structure. From this study, we clearly demonstrated that OT molecules in SAMs on Au(111) are desorbed spontaneously in UHV at room temperature, resulting in the formation of disordered and row phases.

19.
J Nanosci Nanotechnol ; 16(3): 2900-3, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27455730

RESUMO

Novel materials based on Zn(HPB)2 and Ir-complexes were synthesized as blue or red emitters, respectively. White organic light emitting diodes were fabricated using the Zn(HPB)2 as a blue emitting layer, Ir-complexes as a red emitting layer and Alq3 as a green emitting layer. The obtained experimental results, were based on white OLEDs fabricated using double emission layers of Zn(HPB)2 and Alq3:Ir-complexes. The doping rate of the Ir-complexes was varied at 0.4%, 0.6%, 0.8% and 1.0%. When the doping rate of the Alq3:Ir-complexes was 0.6%, a white emission was achieved. The Commission Internationale de l'Eclairage coordinates of the device's white emission were (0.316, 0.331) at an applied voltage of 10.75 V.


Assuntos
Luz , Fluorescência
20.
J Biomed Nanotechnol ; 12(3): 546-53, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27280252

RESUMO

Cleavage of the amyloid precursor protein (APP) by secretases is critical in neural cell processes including the pathway for neural cell proliferation and that underlying the pathogenesis of Alzheimer's disease (AD). Understanding the mechanism of APP cleavage and development of a convenient tool for the accurate evaluation of APP cleavage intensity by secretases are very important in the development of new AD therapeutic targets. In this study, we developed a sophisticated technology to evaluate the APP cleavage mechanism at the nano-molecular level by atomic force microscopic (AFM) nanolithography. APP was modified on a glass substrate; nanolithography of APP cleavage by ß-secretase-modified AFM probe scanning was achieved. APP cleavage was verified by the AFM imaging and the fluorescent immunostaining. The present method will be very useful in understanding the molecular level of the APP cleavage mechanism by ß-secretase in vitro; this method will facilitate inhibitor screening for the therapeutic target of AD.


Assuntos
Secretases da Proteína Precursora do Amiloide/química , Secretases da Proteína Precursora do Amiloide/ultraestrutura , Precursor de Proteína beta-Amiloide/química , Precursor de Proteína beta-Amiloide/ultraestrutura , Microscopia de Força Atômica/métodos , Adsorção , Sítios de Ligação , Ativação Enzimática , Teste de Materiais/métodos , Fotografação/métodos , Impressão Tridimensional , Ligação Proteica
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