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1.
Pathol Res Pract ; 214(10): 1626-1631, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30139555

RESUMEN

This study identified chemotherapeutic agents that up-regulate programmed cell death ligand-1 (PD-L1) and galectin-9 (Gal-9) in breast cancer cells. Immunohistochemical (IHC) staining was used to evaluate changes in PD-L1 and Gal-9 expression in the tumor tissue of triple-negative breast cancer (TNBC) patients who received anthracycline- and taxane-based neoadjuvant chemotherapy. To determine whether PD-L1 and Gal-9 expression changes were attributable directly to chemotherapeutics, MDA-MB-231 cells and HS578T cells were treated with different concentrations of anthracycline and taxane. Expression levels of PD-L1 and Gal-9 were evaluated and the activation status of NFκB in MDA-MB-231 and HS578T cells was determined to identify the PD-L1 and Gal-9 up-regulation mechanism. Three cases of increased PD-L1 expression and two of increased Gal-9 expression were observed among the TNBC patients. PD-L1 and Gal-9 expression were up-regulated by anthracycline and taxane in MDA-MB-231 cells, but not in HS578T cells. Increased nuclear levels of NFκB were observed in MDA-MB-231 cells treated with 0.5 µM epirubicin. Anthracycline and taxane up-regulated PD-L1 and Gal-9 expression in some subtypes of TNBC. This study provides useful reference data for clinical trials investigating combination treatments with immune checkpoint inhibitors and chemotherapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Antígeno B7-H1/biosíntesis , Galectinas/biosíntesis , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Adulto , Antraciclinas/uso terapéutico , Antígeno B7-H1/efectos de los fármacos , Hidrocarburos Aromáticos con Puentes/uso terapéutico , Línea Celular Tumoral , Quimioterapia Adyuvante/métodos , Femenino , Galectinas/efectos de los fármacos , Humanos , Persona de Mediana Edad , Terapia Neoadyuvante/métodos , Taxoides/uso terapéutico , Neoplasias de la Mama Triple Negativas/metabolismo
2.
Opt Express ; 26(5): 5111-5117, 2018 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-29529718

RESUMEN

We demonstrated the growth of crack-free high-quality GaN-based UV vertical LEDs (VLEDs) (λ = 365 nm) on 6-inch sapphire substrates by using an ex-situ sputtered AlN nucleation layer (NL) and compared their performance with that of UV VLEDs with an in situ low temperature (LT) AlGaN NL. The X-ray diffraction (XRD) results showed that the ex-situ AlN sample contained lower densities of screw-type and edge-type threading dislocations than the in situ AlGaN NL sample. The micro-Raman results revealed that the ex-situ AlN sample was under more compressive stress than the in situ AlGaN sample. As the current was increased, the electroluminescence peaks of both of the samples blue-shifted, reached a minimum wavelength at 1000 mA, and then slightly red-shifted. Packaged VLEDs with the ex-situ AlN NL yielded 6.5% higher light output power at 500 mA than that with the in situ AlGaN NL. The maximum EQEs of the VLED with the in situ AlGaN and ex-situ AlN NLs were 43.7% and 48.2%, respectively. Based on the XRD and Raman results, the improved light output power of the ex-situ AlN sample is attributed to the lower density of TDs.

3.
Disabil Rehabil ; 39(10): 1002-1008, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-27216372

RESUMEN

PURPOSE: There is a lack of evidence-based recommendations for the physiotherapeutic intervention specifically for locomotor training in patients with cerebellar ataxia. The purpose of this study is to determine the feasibility and effect of a more specific rehabilitation strategy that aims to improve gait quality in patients with cerebellar ataxia. METHODS: Nineteen patients with degenerative cerebellar ataxia were recruited to participate in the study. The patients participated in a 12-week locomotor training program, two times per week for 1.5 h per session (a total of 24 training sessions). The treatment approach emphasized the relearning of proper gait movement strategies through intensive practice that enhances the patient's perception and control of the essential components of normal gait movement. RESULTS: A quantitative analysis of step-by-step gait performance indicated that postural sway during locomotion was reduced, and the gait movement pattern became more consistent after the 12-week locomotor training program. These improvements in gait stability persisted over the 3-month period following intervention. CONCLUSION: This study provides preliminary evidence that learning-based rehabilitation strategies targeting disease-specific locomotion symptoms may be helpful for reducing ataxic gait and improving motor control during walking in patients with cerebellar dysfunction. Implications for rehabilitation Physiotherapeutic interventions that aim to promote gait stability in cerebellar patients need to create a specific learning context that improve disease-related gait deficits. It is desirable to use explicit instructions to facilitate the conscious awareness and control of body center and posture. As patients reacquire the fundamental gait ability, providing training experience with various locomotor tasks that facilitate the transfer of learning may be helpful to increase generalizability of locomotor intervention.


Asunto(s)
Ataxia Cerebelosa/rehabilitación , Marcha/fisiología , Especialidad de Fisioterapia/métodos , Equilibrio Postural , Adulto , Anciano , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Postura , República de Corea
4.
Molecules ; 21(3): 375, 2016 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-26999102

RESUMEN

Graphene oxide (GO) is a monolayer of carbon atoms that form a dense honeycomb structure, consisting of hydroxyl and epoxide functional groups on the two accessible sides and carboxylic groups at the edges. In contrast, graphene is a two-dimensional sheet of sp2-hybridized carbon atoms packed into a honeycomb lattice. Graphene has great potential for use in biomedical applications due to its excellent physical and chemical properties. In this study, we report a facile and environmentally friendly approach for the synthesis of reduced graphene oxide (rGO) using uric acid (UA). The synthesized uric acid-reduced graphene oxide (UA-rGO) was fully characterized by ultraviolet-visible (UV-Vis) absorption spectra, X-ray diffraction (XRD), dynamic light scattering (DLS), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and Raman spectroscopy. GO and UA-rGO induced a dose-dependent decrease in cell viability and induced cytotoxicity in human ovarian cancer cells. The results from this study suggest that UA-rGO could cause apoptosis in mammalian cells. The toxicity of UA-rGO is significantly higher than GO. Based on our findings, UA-rGO shows cytotoxic effects against human ovarian cancer cells, and its synthesis is environmentally friendly. UA-rGO significantly inhibits cell viability by increasing lactate dehydrogenase (LDH) release, reactive oxygen species (ROS) generation, activation of caspase-3, and DNA fragmentation. This is the first report to describe the comprehensive effects of UA-rGO in ovarian cancer cells. We believe that the functional aspects of newly synthesized UA-rGO will provide advances towards various biomedical applications in the near future.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Grafito/química , Grafito/farmacología , Óxidos/química , Animales , Caspasa 3/metabolismo , Línea Celular Tumoral , Membrana Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Fragmentación del ADN/efectos de los fármacos , Grafito/síntesis química , Humanos , Especies Reactivas de Oxígeno , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Propiedades de Superficie , Difracción de Rayos X
5.
Materials (Basel) ; 8(10): 6728-6737, 2015 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-28793596

RESUMEN

We evaluated the strength and durability characteristics of latex-polymer-modified, pre-packed pavement repair concrete (LMPPRC) with a rapid-set binder. The rapid-set binder was a mixture of rapid-set cement and silica sand, where the fluidity was controlled using a latex polymer. The resulting mix exhibited a compressive strength of ¥21 MPa and a flexural strength of ¥3.5 MPa after 4 h of curing (i.e., the traffic opening term for emergency repairs of pavement). The ratio of latex polymer to rapid-set binder material was varied through 0.40, 0.33, 0.29, and 0.25. Mechanical characterization revealed that the mechanical performance, permeability, and impact resistance increased as the ratio of latex polymer to rapid-set binder decreased. The mixture exhibited a compressive strength of ¥21 MPa after 4 h when the ratio of latex polymer to rapid-set binder material was ¤0.29. The mixture exhibited a flexural strength of ¥3.5 MPa after 4 h when the ratio of latex polymer to rapid-set binder material was ¤0.33. The permeability resistance to chloride ions satisfied 2000 C after 7 days of curing for all ratios. The ratio of latex polymer to rapid-set binder material that satisfied all conditions for emergency pavement repair was ¤0.29.

6.
Nanoscale Res Lett ; 9(1): 248, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24940177

RESUMEN

Gold nanoparticles (AuNPs) are a fascinating class of nanomaterial that can be used for a wide range of biomedical applications, including bio-imaging, lateral flow assays, environmental detection and purification, data storage, drug delivery, biomarkers, catalysis, chemical sensors, and DNA detection. Biological synthesis of nanoparticles appears to be simple, cost-effective, non-toxic, and easy to use for controlling size, shape, and stability, which is unlike the chemically synthesized nanoparticles. The aim of this study was to synthesize homogeneous AuNPs using pharmaceutically important Ganoderma spp. We developed a simple, non-toxic, and green method for water-soluble AuNP synthesis by treating gold (III) chloride trihydrate (HAuCl4) with a hot aqueous extract of the Ganoderma spp. mycelia. The formation of biologically synthesized AuNPs (bio-AuNPs) was characterized by ultraviolet (UV)-visible absorption spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray (EDX), dynamic light scattering (DLS), and transmission electron microscopy (TEM). Furthermore, the biocompatibility of as-prepared AuNPs was evaluated using a series of assays, such as cell viability, lactate dehydrogenase leakage, and reactive oxygen species generation (ROS) in human breast cancer cells (MDA-MB-231). The color change of the solution from yellow to reddish pink and strong surface plasmon resonance were observed at 520 nm using UV-visible spectroscopy, and that indicated the formation of AuNPs. DLS analysis revealed the size distribution of AuNPs in liquid solution, and the average size of AuNPs was 20 nm. The size and morphology of AuNPs were investigated using TEM. The biocompatibility effect of as-prepared AuNPs was investigated in MDA-MB-231 breast cancer cells by using various concentrations of AuNPs (10 to 100 µM) for 24 h. Our findings suggest that AuNPs are non-cytotoxic and biocompatible. To the best of our knowledge, this is the first report to describe the synthesis of monodispersed, biocompatible, and soluble AuNPs with an average size of 20 nm using Ganoderma spp. This study opens up new possibilities of using an inexpensive and non-toxic mushroom extract as a reducing and stabilizing agent for the synthesis of size-controlled, large-scale, biocompatible, and monodispersed AuNPs, which may have future diagnostic and therapeutic applications.

7.
Development ; 141(11): 2235-44, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24866115

RESUMEN

Recently, the concept of 'neo-oogenesis' has received increasing attention, since it was shown that adult mammals have a renewable source of eggs. The purpose of this study was to elucidate the origin of these eggs and to confirm whether neo-oogenesis continues throughout life in the ovaries of the adult mammal. Adult female pigs were utilized to isolate, identify and characterize, including their proliferation and differentiation capabilities, putative stem cells (PSCs) from the ovary. PSCs were found to comprise a heterogeneous population based on c-kit expression and cell size, and also express stem and germ cell markers. Analysis of PSC molecular progression during establishment showed that these cells undergo cytoplasmic-to-nuclear translocation of Oct4 in a manner reminiscent of gonadal primordial germ cells (PGCs). Hence, cells with the characteristics of early PGCs are present or are generated in the adult pig ovary. Furthermore, the in vitro establishment of porcine PSCs required the presence of ovarian cell-derived extracellular regulatory factors, which are also likely to direct stem cell niche interactions in vivo. In conclusion, the present work supports a crucial role for c-kit and kit ligand/stem cell factor in stimulating the growth, proliferation and nuclear reprogramming of porcine PSCs, and further suggests that porcine PSCs might be the culture equivalent of early PGCs.


Asunto(s)
Ovario/citología , Células Madre/citología , Animales , Diferenciación Celular , Proliferación Celular , Reprogramación Celular , Medios de Cultivo , Femenino , Células Germinativas/citología , Estratos Germinativos/metabolismo , Cariotipificación , Ligandos , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Oogénesis , Folículo Ovárico/citología , Proteínas Proto-Oncogénicas c-kit/metabolismo , Factor de Células Madre/metabolismo , Nicho de Células Madre , Porcinos
8.
Int J Nanomedicine ; 9: 1783-97, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24741313

RESUMEN

BACKGROUND: Recently, graphene and graphene-related materials have attracted much attention due their unique properties, such as their physical, chemical, and biocompatibility properties. This study aimed to determine the cytotoxic effects of graphene oxide (GO) that is reduced biologically using Ganoderma spp. mushroom extracts in MDA-MB-231 human breast cancer cells. METHODS: Herein, we describe a facile and green method for the reduction of GO using extracts of Ganoderma spp. as a reducing agent. GO was reduced without any hazardous chemicals in an aqueous solution, and the reduced GO was characterized using a range of analytical procedures. The Ganoderma extract (GE)-reduced GO (GE-rGO) was characterized by ultraviolet-visible absorption spectroscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, dynamic light scattering, scanning electron microscopy, Raman spectroscopy, and atomic force microscopy. Furthermore, the toxicity of GE-rGO was evaluated using a sequence of assays such as cell viability, lactate dehydrogenase leakage, and reactive oxygen species generation in human breast cancer cells (MDA-MB-231). RESULTS: The preliminary characterization of reduction of GO was confirmed by the red-shifting of the absorption peak for GE-rGO to 265 nm from 230 nm. The size of GO and GE-rGO was found to be 1,880 and 3,200 nm, respectively. X-ray diffraction results confirmed that reduction processes of GO and the processes of removing intercalated water molecules and the oxide groups. The surface functionalities and chemical natures of GO and GE-rGO were confirmed using Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. The surface morphologies of the synthesized graphene were analyzed using high-resolution scanning electron microscopy. Raman spectroscopy revealed single- and multilayer properties of GE-rGO. Atomic force microscopy images provided evidence for the formation of graphene. Furthermore, the effect of GO and GE-rGO was examined using a series of assays, such as cell viability, membrane integrity, and reactive oxygen species generation, which are key molecules involved in apoptosis. The results obtained from cell viability and lactate dehydrogenase assay suggest that GO and GE-rGO cause dose-dependent toxicity in the cells. Interestingly, it was found that biologically derived GE-rGO is more toxic to cancer cells than GO. CONCLUSION: We describe a simple, green, nontoxic, and cost-effective approach to producing graphene using mushroom extract as a reducing and stabilizing agent. The proposed method could enable synthesis of graphene with potential biological and biomedical applications such as in cancer and angiogenic disorders. To our knowledge, this is the first report using mushroom extract as a reducing agent for the synthesis of graphene. Mushroom extract can be used as a biocatalyst for the production of graphene.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Extractos Celulares/química , Ganoderma/química , Grafito/administración & dosificación , Grafito/síntesis química , Nanopartículas/administración & dosificación , Nanopartículas/química , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/patología , Fraccionamiento Celular , Línea Celular Tumoral , Humanos , Oxidación-Reducción , Óxidos/administración & dosificación , Óxidos/química
9.
Colloids Surf B Biointerfaces ; 111: 376-83, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-23850746

RESUMEN

The synthesis of graphene nanosheets from graphene oxide is an interesting area of nanobiotechnology because graphene-based nanomaterials have potential applications in the biomedical field. In this study, we developed a green, rapid, and simple method for the synthesis of graphene from graphene oxide, which uses the mitochondrial polypeptide humanin as a reducing agent. Graphene was prepared via one-step reduction of graphene oxide under mild conditions in an aqueous solution, and the resulting substance was characterized using a range of analytical procedures. UV-vis absorption spectroscopy confirmed the reduction of graphene oxide to graphene. Fourier transform infrared spectroscopy was used to study the changes in the surface functionalities, and X-ray diffraction was used to investigate the crystal structure of graphene. High resolution scanning electron microscopy and atomic force microscopy were also employed to investigate the morphologies of the synthesized grapheme, and Raman spectroscopy was used to evaluate its single- and multi-layer properties. The results described here suggest that the potent reducing agent humanin may be used as a substitute for hydrazine during graphene synthesis, thereby providing a safe, biocompatible and green method for the efficient deoxygenation of graphene oxide that can be used for large-scale production and biomedical applications.


Asunto(s)
Grafito/química , Tecnología Química Verde/métodos , Péptidos y Proteínas de Señalización Intracelular/química , Conductividad Eléctrica , Humanos , Luz , Microscopía de Fuerza Atómica , Oxidación-Reducción , Tamaño de la Partícula , Dispersión de Radiación , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Termogravimetría , Difracción de Rayos X
10.
Biol Reprod ; 88(4): 88, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23467739

RESUMEN

Embryo development is a complex and tightly controlled process. Nanoparticle injury can affect normal development and lead to malformation or miscarriage of the embryo. However, the risk that these nanoparticles may pose to reproduction is not clear. In this study, chitosan nanoparticles (CSNP) of near uniform size, in the range of 100 nm, were synthesized and confirmed by a particle size analyzer and transmission electron microscopy. Morulae-stage embryo exposure to CSNP during in vitro culture caused blastocyst complications that had either no cavity or a small cavity. Furthermore, CSNP-treated embryos showed lower expression of not only trophectoderm-associated genes but also pluripotent marker genes. When blastocysts developed in both media with and without CSNP were transferred to recipients, the percentage of blastocysts resulting in viable pups was significantly reduced. These detrimental effects are linked to the reduction of total cell numbers, enhanced apoptosis, and abnormal blastocoels forming at the blastocyst stage, indicating that CSNP treatment might have long-term adverse biological effects in view of pregnancy outcome.


Asunto(s)
Quitosano/efectos adversos , Desarrollo Embrionario/efectos de los fármacos , Nanopartículas/efectos adversos , Aborto Espontáneo/inducido químicamente , Animales , Blastocisto/citología , Blastocisto/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Quitosano/administración & dosificación , Transferencia de Embrión , Femenino , Ratones , Ratones Endogámicos ICR , Nanopartículas/administración & dosificación , Embarazo
11.
Cell Reprogram ; 14(4): 353-63, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22775484

RESUMEN

In this study, we examined whether Hanganutziu-Deicher (H-D) antigens are important as an immunogenic non-α1,3-galactose (Gal) epitope in pigs with a disrupted α1,3-galactosyltransferase gene. The targeting efficiency of the AO blood genotype was achieved (2.2%) in pig fibroblast cells. A total of 1800 somatic cell nuclear transfer (SCNT) embryos were transferred to 10 recipients. One recipient developed to term and naturally delivered two piglets. The α1,3-galactosyltransferase activity in lung, liver, spleen, and testis of heterozygote α1,3-galactosyltransferase gene knockout (GalT-KO) pigs was significantly decreased, whereas brain and heart showed very low decreasing levels of α1,3-galactosyltransferase activity when compared to those of control. Enzyme-linked lectinosorbent assay showed that the heterozygote GalT-KO pig had more sialylα2,6- and sialylα2,3-linked glycan than the control. Furthermore, the heart, liver, and kidney of the heterozygote GalT-KO pig had a higher N-glycolylneuraminic acid (Neu5Gc) content than the control, whereas the lung of the heterozygote GalT-KO pig had Neu5Gc content similar to the control. Collectively, the data strongly indicated that Neu5Gc is a more critical xenoantigen to overcoming the next acute immune rejection in pig to human xenotransplantation.


Asunto(s)
Animales Modificados Genéticamente/genética , Antígenos Heterófilos , Clonación de Organismos , Galactosiltransferasas , Técnicas de Silenciamiento del Gen , Ácidos Neuramínicos , Técnicas de Transferencia Nuclear , Animales , Humanos , Porcinos , Porcinos Enanos , Trasplante Heterólogo
12.
J Biomed Biotechnol ; 2011: 560850, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22131812

RESUMEN

We examined whether deficiency of the GGTA1 gene in pigs altered the expression of several glycosyltransferase genes. Real-time RT-PCR and glycosyltransferase activity showed that 2 sialyltransferases [α2,3-sialyltransferase (α2,3ST) and α2,6-sialyltransferase (α2,6ST)] in the heterozygote GalT KO liver have higher expression levels and activities compared to controls. Enzyme-linked lectin assays indicated that there were also more sialic acid-containing glycoconjugate epitopes in GalT KO livers than in controls. The elevated level of sialic-acid-containing glycoconjugate epitopes was due to the low level of α-Gal in heterozygote GalT KO livers. Furthermore, proteomics analysis showed that heterozygote GalT KO pigs had a higher expression of NAD+-isocitrate dehydrogenase (IDH), which is related to the CMP-N-acetylneuraminic acid hydroxylase (CMAH) enzyme reaction. These findings suggest the deficiency of GGTA1 gene in pigs results in increased production of N-glycolylneuraminic acid (Neu5Gc) due to an increase of α2,6-sialyltransferase and a CMAH cofactor, NAD+-IDH. This indicates that Neu5Gc may be a critical xenoantigen. The deletion of the CMAH gene in the GalT KO background is expected to further prolong xenograft survival.


Asunto(s)
Antígenos Heterófilos/metabolismo , Galactosiltransferasas/deficiencia , Glicoproteínas/metabolismo , Hígado/enzimología , Neuraminidasa/metabolismo , Sialiltransferasas/metabolismo , Porcinos/metabolismo , Animales , Epítopos/metabolismo , Galactosiltransferasas/genética , Eliminación de Gen , Glicoconjugados/metabolismo , Glicoproteínas/genética , Isocitrato Deshidrogenasa/metabolismo , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Ácidos Neuramínicos/metabolismo , Neuraminidasa/genética , Sialiltransferasas/genética , Porcinos/genética , beta-D-Galactósido alfa 2-6-Sialiltransferasa
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