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1.
Cell ; 173(2): 430-442.e17, 2018 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-29606353

RESUMEN

Fetal hemoglobin (HbF, α2γ2) level is genetically controlled and modifies severity of adult hemoglobin (HbA, α2ß2) disorders, sickle cell disease, and ß-thalassemia. Common genetic variation affects expression of BCL11A, a regulator of HbF silencing. To uncover how BCL11A supports the developmental switch from γ- to ß- globin, we use a functional assay and protein binding microarray to establish a requirement for a zinc-finger cluster in BCL11A in repression and identify a preferred DNA recognition sequence. This motif appears in embryonic and fetal-expressed globin promoters and is duplicated in γ-globin promoters. The more distal of the duplicated motifs is mutated in individuals with hereditary persistence of HbF. Using the CUT&RUN approach to map protein binding sites in erythroid cells, we demonstrate BCL11A occupancy preferentially at the distal motif, which can be disrupted by editing the promoter. Our findings reveal that direct γ-globin gene promoter repression by BCL11A underlies hemoglobin switching.


Asunto(s)
Proteínas Portadoras/metabolismo , Hemoglobina Fetal/genética , Proteínas Nucleares/metabolismo , Secuencia de Bases , Sitios de Unión , Proteínas Portadoras/genética , Línea Celular , Cromatina/metabolismo , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Células Eritroides/citología , Células Eritroides/metabolismo , Edición Génica , Humanos , Proteínas Nucleares/genética , Regiones Promotoras Genéticas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Represoras , Dedos de Zinc/genética , Globinas beta/genética , Talasemia beta/genética , Talasemia beta/patología , gamma-Globinas/genética
2.
Sensors (Basel) ; 21(24)2021 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-34960429

RESUMEN

Rail corrugation appears as oscillatory wear on the rail surface caused by the interaction between the train wheels and the railway. Corrugation shortens railway service life and forces early rail replacement. Consequently, service can be suspended for days during rail replacement, adversely affecting an important means of transportation. We propose an inspection method for rail corrugation using computer vision through an algorithm based on feature descriptors to automatically distinguish corrugated from normal surfaces. We extract seven features and concatenate them to form a feature vector obtained from a railway image. The feature vector is then used to build support vector machine. Data were collected from seven different tracks as video streams acquired at 30 fps. The trained support vector machine was used to predict test frames of rails as being either corrugated or normal. The proposed method achieved a high performance, with 97.11% accuracy, 95.52% precision, and 97.97% recall. Experimental results show that our method is more effective in identifying corrugated images than reference state-of the art works.


Asunto(s)
Algoritmos , Máquina de Vectores de Soporte , Computadores , Transportes
3.
Pharmacol Res ; 160: 105147, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32814167

RESUMEN

EPHB6 is a metastasis inhibitory gene that is frequently decreased or deficiency in non-small cell lung cancer (NSCLC), which contributed to the subsequent development of distant metastasis. These suggested the possibility that reactivation of EPHB6 might prevent the metastasis of NSCLC. Nevertheless, EPHB6 expression might also promote cancer cell growth and inhibit cell apoptosis by activating Akt and ERK pathway, apart from inhibition of migration and invasion. In the present study, we developed a novel quinazolin-4(3H)-one analog (DFX24) as a potential PI3Kα inhibitor, which inhibited both cell proliferation and metastasis of NSCLC cell lines. Investigation to the molecular mechanisms revealed DFX24 inhibited the cell growth and metastasis via inhibition of PI3Kα and ERK activity, as well as the increase in EPHB6 expression. In addition, DFX24 also induced cell cycle arrest and tumor cell apoptosis by inhibiting PI3K/Akt pathway and activating mitochondria-dependent pathway, respectively. These findings suggested that DFX24 might be considered as a novel drug candidate and may provide a potential therapy for NSCLC.


Asunto(s)
Antineoplásicos/farmacología , Derivados del Benceno/farmacología , Carcinoma de Pulmón de Células no Pequeñas/prevención & control , Neoplasias Pulmonares/prevención & control , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Morfolinas/farmacología , Metástasis de la Neoplasia/prevención & control , Fosfatidilinositol 3-Quinasas/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Piridinas/farmacología , Quinazolinas/farmacología , Receptores de la Familia Eph/efectos de los fármacos , Receptores de la Familia Eph/metabolismo , Sulfonamidas/farmacología , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Proteína Oncogénica v-akt/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
4.
Molecules ; 25(3)2020 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-31979361

RESUMEN

Oxypeucedanin (OPD), a furocoumarin compound from Angelica dahurica (Umbelliferae), exhibits potential antiproliferative activities in human cancer cells. However, the underlying molecular mechanisms of OPD as an anticancer agent in human hepatocellular cancer cells have not been fully elucidated. Therefore, the present study investigated the antiproliferative effect of OPD in SK-Hep-1 human hepatoma cells. OPD effectively inhibited the growth of SK-Hep-1 cells. Flow cytometric analysis revealed that OPD was able to induce G2/M phase cell cycle arrest in cells. The G2/M phase cell cycle arrest by OPD was associated with the downregulation of the checkpoint proteins cyclin B1, cyclin E, cdc2, and cdc25c, and the up-regulation of p-chk1 (Ser345) expression. The growth-inhibitory activity of OPD against hepatoma cells was found to be p53-dependent. The p53-expressing cells (SK-Hep-1 and HepG2) were sensitive, but p53-null cells (Hep3B) were insensitive to the antiproliferative activity of OPD. OPD also activated the expression of p53, and thus leading to the induction of MDM2 and p21, which indicates that the antiproliferative activity of OPD is in part correlated with the modulation of p53 in cancer cells. In addition, the combination of OPD with gemcitabine showed synergistic growth-inhibitory activity in SK-Hep-1 cells. These findings suggest that the anti-proliferative activity of OPD may be highly associated with the induction of G2/M phase cell cycle arrest and upregulation of the p53/MDM2/p21 axis in SK-HEP-1 hepatoma cells.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Furocumarinas/farmacología , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Neoplasias Hepáticas/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Angelica/química , Protocolos de Quimioterapia Combinada Antineoplásica , Proteína Quinasa CDC2/metabolismo , Carcinoma Hepatocelular/metabolismo , Proliferación Celular/efectos de los fármacos , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/metabolismo , Ciclina B1/metabolismo , Ciclina E/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Sinergismo Farmacológico , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Transducción de Señal/efectos de los fármacos , Fosfatasas cdc25/metabolismo , Gemcitabina
5.
Mediators Inflamm ; 2019: 7651470, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31182933

RESUMEN

Lumbar spinal stenosis (LSS) is a major cause of chronic low back pain; however, only a few therapies which have been used in clinics still have limited effects on functional recovery. SHINBARO2 is a refined traditional formulation for inflamed lesions and relieve pain of muscular skeletal disease. This study aimed at investigating the effects of SHINBARO2 on LSS and at determining its underlying molecular mechanism in rat models. The LSS rat models were set up by surgical operations in 6-week-old male Sprague-Dawley rats. SHINBARO2 was orally or intraperitoneally administered for 14 days. The motor and sensory ability of rats were evaluated using the activity cage and hot plate method. On the termination day, total vertebrae including the disc and spinal cord were excised for ex vivo study. SHINBARO2 improved locomotor functions and pain sensitivity in LSS rat models. Mechanism study suggested that SHINBARO2 inhibited the production of nitric oxide and prostaglandin E2 in tissues from LSS-induced rats. SHINBARO2 also suppressed the expression of proinflammatory cytokines including tumor necrosis factor-α and interleukin-1ß. The activation of NF-κB by LSS surgery was effectively reduced by SHINBARO2, which coincided with the inhibition of IκB degradation. In addition, brain-derived neurotrophic factor (BDNF), a potent promoter of neurite growth, and its downstream ERK signaling were also regulated by SHINBARO2. These findings suggest that the effect of SHINBARO2 might be associated in part with the anti-inflammation and pain control in LSS rat models.


Asunto(s)
Antiinflamatorios/uso terapéutico , Estenosis Espinal/tratamiento farmacológico , Animales , Antiinflamatorios/química , Western Blotting , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Inmunohistoquímica , Interleucina-1beta/metabolismo , Locomoción/fisiología , Masculino , FN-kappa B/metabolismo , Ratas , Ratas Sprague-Dawley , Estenosis Espinal/inmunología , Estenosis Espinal/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
6.
J Dairy Sci ; 102(12): 10845-10849, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31629522

RESUMEN

The aim of this study was to analyze the ß-glucan contents, physicochemical features, and microbial communities in milk kefir prepared using Saccharomyces cerevisiae KU200284 isolated from cucumber jangajji, a fermented vegetable commonly eaten in Korean. Three types of milk kefir were manufactured, with (1) activated kefir grain, (2) activated kefir grain with commercial S. cerevisiae BOF, and (3) activated kefir grain with S. cerevisiae KU200284. ß-Glucan contents of milk kefir using kefir grain and kefir grain with S. cerevisiae strains BOF and KU200284 were 8.29, 8.59, and 8.57%, respectively. The pH, titratable acidity, viscosity, Brix level, and alcohol contents of milk kefir using kefir grain with S. cerevisiae strains were acceptable compared with milk kefir using only kefir grain. In milk kefir produced using kefir grains and S. cerevisiae strains, 16S rRNA reads showed representative strains of Lactobacillus kefiranofaciens (>72% relative abundance) and Acetobacter fabarum (>16% relative abundance). In particular, milk kefir using kefir grain with S. cerevisiae KU200284 had the highest relative abundance of L. kefiranofaciens. In addition, the internal transcribed sequence (ITS) rRNA reads in tested milk kefir showed representative strains of Kluyveromyces marxianus (>52% relative abundance) and Saccharomyces cerevisiae (>16% relative abundance). In contrast, milk kefir using S. cerevisiae strains had higher relative abundance of S. cerevisiae (>37%). The ß-glucan production, physicochemical properties, and microbial community profiling indicate that S. cerevisiae KU200284 could be used in functional dairy products as a starter culture.


Asunto(s)
Kéfir/microbiología , Probióticos/metabolismo , Saccharomyces cerevisiae/metabolismo , Acetobacter/aislamiento & purificación , Animales , Fermentación , Kluyveromyces/aislamiento & purificación , Lactobacillus/aislamiento & purificación , Microbiota , ARN Ribosómico 16S , beta-Glucanos/análisis
7.
Int J Mol Sci ; 20(24)2019 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-31835356

RESUMEN

Electrospinning has gained great interest in the field of regenerative medicine, due to its fabrication of a native extracellular matrix-mimicking environment. The micro/nanofibers generated through this process provide cell-friendly surroundings which promote cellular activities. Despite these benefits of electrospinning, a process was introduced to overcome the limitations of electrospinning. Cell-electrospinning is based on the basic process of electrospinning for producing viable cells encapsulated in the micro/nanofibers. In this review, the process of cell-electrospinning and the materials used in this process will be discussed. This review will also discuss the applications of cell-electrospun structures in tissue engineering. Finally, the advantages, limitations, and future perspectives will be discussed.


Asunto(s)
Materiales Biomiméticos/química , Matriz Extracelular/química , Nanofibras/química , Ingeniería de Tejidos , Andamios del Tejido/química , Animales , Humanos , Medicina Regenerativa
8.
Int J Cancer ; 141(2): 220-230, 2017 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-28240776

RESUMEN

Chemotherapy, one of the principal approaches for cancer patients, plays a crucial role in controlling tumor progression. Clinically, tumors reveal a satisfactory response following the first exposure to the chemotherapeutic drugs in treatment. However, most tumors sooner or later become resistant to even chemically unrelated anticancer agents after repeated treatment. The reduced drug accumulation in tumor cells is considered one of the significant mechanisms by decreasing drug permeability and/or increasing active efflux (pumping out) of the drugs across the cell membrane. The mechanisms of treatment failure of chemotherapeutic drugs have been investigated, including drug efflux, which is mediated by extracellular vesicles (EVs). Exosomes, a subset of EVs with a size range of 40-150 nm and a lipid bilayer membrane, can be released by all cell types. They mediate specific cell-to-cell interactions and activate signaling pathways in cells they either fuse with or interact with, including cancer cells. Exosomal RNAs are heterogeneous in size but enriched in small RNAs, such as miRNAs. In the primary tumor microenvironment, cancer-secreted exosomes and miRNAs can be internalized by other cell types. MiRNAs loaded in these exosomes might be transferred to recipient niche cells to exert genome-wide regulation of gene expression. How exosomal miRNAs contribute to the development of drug resistance in the context of the tumor microenvironment has not been fully described. In this review, we will highlight recent studies regarding EV-mediated microRNA delivery in formatting drug resistance. We also suggest the use of EVs as an advancing method in antiresistance treatment.


Asunto(s)
Resistencia a Antineoplásicos , Exosomas/metabolismo , MicroARNs/genética , Neoplasias/genética , Animales , Antineoplásicos/uso terapéutico , Comunicación Celular , Exosomas/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Transducción de Señal , Microambiente Tumoral
9.
Development ; 141(7): 1480-91, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24574008

RESUMEN

Neurovascular alignment is a common anatomical feature of organs, but the mechanisms leading to this arrangement are incompletely understood. Here, we show that vascular endothelial growth factor (VEGF) signaling profoundly affects both vascularization and innervation of the pancreatic islet. In mature islets, nerves are closely associated with capillaries, but the islet vascularization process during embryonic organogenesis significantly precedes islet innervation. Although a simple neuronal meshwork interconnects the developing islet clusters as they begin to form at E14.5, the substantial ingrowth of nerve fibers into islets occurs postnatally, when islet vascularization is already complete. Using genetic mouse models, we demonstrate that VEGF regulates islet innervation indirectly through its effects on intra-islet endothelial cells. Our data indicate that formation of a VEGF-directed, intra-islet vascular plexus is required for development of islet innervation, and that VEGF-induced islet hypervascularization leads to increased nerve fiber ingrowth. Transcriptome analysis of hypervascularized islets revealed an increased expression of extracellular matrix components and axon guidance molecules, with these transcripts being enriched in the islet-derived endothelial cell population. We propose a mechanism for coordinated neurovascular development within pancreatic islets, in which endocrine cell-derived VEGF directs the patterning of intra-islet capillaries during embryogenesis, forming a scaffold for the postnatal ingrowth of essential autonomic nerve fibers.


Asunto(s)
Vasos Sanguíneos/fisiología , Comunicación Celular/genética , Islotes Pancreáticos/irrigación sanguínea , Islotes Pancreáticos/inervación , Neovascularización Fisiológica/fisiología , Factor A de Crecimiento Endotelial Vascular/fisiología , Animales , Vasos Sanguíneos/embriología , Células Cultivadas , Embrión de Mamíferos , Endotelio Vascular/embriología , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiología , Femenino , Islotes Pancreáticos/embriología , Ratones , Ratones Transgénicos , Factor A de Crecimiento Endotelial Vascular/genética
10.
Bioorg Med Chem ; 25(13): 3396-3405, 2017 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-28478865

RESUMEN

The overproduction of nitric oxide (NO) plays an important role in a variety of pathophysiological processes, including inflammation. Therefore, the suppression of NO production is a promising target in the design of anti-inflammatory agents. In the present study, a series of phthalimide analogs was synthesized, and their anti-inflammatory activities were evaluated using lipopolysaccharide (LPS)-stimulated NO production in cultured murine macrophage RAW264.7 cells. A structure-activity relationship study showed that the free hydroxyl group at C-4 and C-6 and the bulkiness of the N-substituted alkyl chain are associated with biological activity. Among the series of phthalimide derivatives, compound IIh exhibited potent inhibitory activity, with an IC50 value of 8.7µg/mL. Further study revealed that the inhibitory activity of compound IIh was correlated with the down-regulation of the mRNA and protein expression of LPS-stimulated inducible nitric oxide synthase (iNOS). Compound IIh also suppressed the induction of the pro-inflammatory cytokines tumor necrosis factor-α and interleukin-1ß in LPS-stimulated RAW 264.7 cells. The anti-inflammatory activity of compound IIh was also found to be associated with the suppression of the Toll-like receptor (TLR)4 signaling pathway by down-regulating the activation of interferon regulatory factor 3 (IRF-3) and interferon-ß and signal transducer expression. These findings demonstrate that novel phthalimides might be potential candidates for the development of anti-inflammatory agents.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Citocinas/antagonistas & inhibidores , Lipopolisacáridos/antagonistas & inhibidores , Óxido Nítrico Sintasa de Tipo II/antagonistas & inhibidores , Óxido Nítrico/antagonistas & inhibidores , Ftalimidas/farmacología , Animales , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Citocinas/metabolismo , Relación Dosis-Respuesta a Droga , Lipopolisacáridos/farmacología , Ratones , Estructura Molecular , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa de Tipo II/metabolismo , Ftalimidas/síntesis química , Ftalimidas/química , Células RAW 264.7 , Relación Estructura-Actividad
11.
J Nat Prod ; 79(4): 1097-104, 2016 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-27064730

RESUMEN

The antitumor activity of spicatoside A (1), a steroidal saponin isolated from the tuber of Liriope platyphylla, and its underlying mechanisms were investigated in HCT116 human colorectal cancer cells. Compound 1 induced autophagy and apoptotic cell death and inhibited tumor growth in a nude mouse xenograft model implanted with HCT116 cells. Treatment with 1 for 24 h enhanced the formation of acidic vesicular organelles in the cytoplasm, indicating the induction of the onset of autophagy. This event was associated with the regulation of autophagic markers including microtubule-associated protein 1 light chain 3 (LC3)-II, p62, beclin 1, lysosomal-associated membrane protein 1 (LAMP 1), and cathepsin D by inhibiting the PI3K/Akt/mTOR signaling pathway, regulating mitogen-activated protein kinase (MAPK) signaling, and increasing p53 levels. However, a prolonged exposure to 1 resulted in apoptosis characterized by the accumulation of a sub-G1 cell population and an annexin V/propidium iodide (PI)-positive cell population. Apoptosis induced by 1 was associated with the regulation of apoptotic proteins including Bcl-2, Bax, and Bid, the release of cytochrome c into the cytosol, and the accumulation of cleaved poly-ADP-ribose polymerase (PARP). Further study revealed that cleavage of beclin 1 by caspases plays a critical role in the 1-mediated switch from autophagy to apoptosis. Taken together, these findings highlight the significance of 1 in the modulation of crosstalk between autophagy and apoptosis, as well as the potential use of 1 as a novel candidate in the treatment of human colorectal cancer cells.


Asunto(s)
Autofagia/efectos de los fármacos , Liliaceae/química , Saponinas/farmacología , Animales , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis , Beclina-1 , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales , Células HCT116 , Humanos , Proteínas de la Membrana , Ratones , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Estructura Molecular , Fosfatidilinositol 3-Quinasas/metabolismo , Saponinas/química , Saponinas/aislamiento & purificación , Transducción de Señal/efectos de los fármacos
12.
Molecules ; 21(12)2016 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-27999400

RESUMEN

Probiotics have been demonstrated as a new paradigm to substitute antibiotic treatment for dental caries, gingivitis, and chronic periodontitis. The present work was conducted to compare the characteristics of oral care probiotics: Weissella cibaria CMU (Chonnam Medical University) and four commercial probiotic strains. Survival rates under poor oral conditions, acid production, hydrogen peroxide production, as well as inhibition of biofilm formation, coaggregation, antibacterial activity, and inhibition of volatile sulfur compounds were evaluated. The viability of W. cibaria CMU was not affected by treatment of 100 mg/L lysozyme for 90 min and 1 mM hydrogen peroxide for 6 h. Interestingly, W. cibaria produced less acid and more hydrogen peroxide than the other four probiotics. W. cibaria inhibited biofilm formation by Streptococcus mutans at lower concentrations (S. mutans/CMU = 8) and efficiently coaggregated with Fusobacterium nucleatum. W. cibaria CMU and two commercial probiotics, including Lactobacillus salivarius and Lactobacillus reuteri, showed high antibacterial activities (>97%) against cariogens (S. mutans and Streptococcus sobrinus), and against periodontopathogens (F. nucleatum and Porphyromonas gingivalis). All of the lactic acid bacterial strains in this study significantly reduced levels of hydrogen sulfide and methyl mercaptan produced by F. nucleatum and P. gingivalis (p < 0.05). These results suggest that W. cibaria CMU is applicable as an oral care probiotic.


Asunto(s)
Biopelículas , Caries Dental/prevención & control , Probióticos , Weissella/metabolismo , Fusobacterium/fisiología , Peróxido de Hidrógeno/metabolismo , Lactobacillus/metabolismo , Muramidasa/metabolismo , Streptococcus mutans/fisiología , Compuestos de Azufre/metabolismo
13.
Korean J Physiol Pharmacol ; 20(4): 367-78, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27382353

RESUMEN

Recently, it was reported that the role of mitochondria-reactive oxygen species (ROS) generating pathway in cisplatin-induced apoptosis is remarkable. Since a variety of molecules are involved in the pathway, a comprehensive approach to delineate the biological interactions of the molecules is required. However, quantitative modeling of the mitochondria-ROS generating pathway based on experiment and systemic analysis using the model have not been attempted so far. Thus, we conducted experiments to measure the concentration changes of critical molecules associated with mitochondrial apoptosis in both human mesothelioma H2052 and their ρ(0) cells lacking mitochondrial DNA (mtDNA). Based on the experiments, a novel mathematical model that can represent the essential dynamics of the mitochondrial apoptotic pathway induced by cisplatin was developed. The kinetic parameter values of the mathematical model were estimated from the experimental data. Then, we have investigated the dynamical properties of this model and predicted the apoptosis levels for various concentrations of cisplatin beyond the range of experiments. From parametric perturbation analysis, we further found that apoptosis will reach its saturation level beyond a certain critical cisplatin concentration.

14.
Virol J ; 12: 27, 2015 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-25886579

RESUMEN

BACKGROUND: Enteroviruses (EVs) are the leading cause of aseptic meningitis worldwide. Detection of enteroviral RNA in clinical specimens has been demonstrated to improve the management of patient care, especially that of neonates and young children. FINDINGS: To establish a sensitive and reliable assay for routine laboratory diagnosis, we compared the sensitivity and specificity of the GeneXpert Enterovirus Assay (GXEA) with that of the reverse transcription polymerase chain reaction (RT-PCR) based assay referred to as real-time one step RT-PCR (RTo-PCR). The sensitivity/specificity produced by GXEA and RTo-PCR were 100%/100% and 65%/100%, respectively. CONCLUSIONS: Both methods evaluated in this article can be used for detection of enterovirus in clinical specimens and these nucleic acid amplification methods are useful assays for the diagnosis of enteroviral infection.


Asunto(s)
Infecciones por Enterovirus/virología , Enterovirus/aislamiento & purificación , Meningitis/virología , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Enterovirus/genética , Infecciones por Enterovirus/líquido cefalorraquídeo , Infecciones por Enterovirus/diagnóstico , Humanos , Meningitis/líquido cefalorraquídeo , Meningitis/diagnóstico , Técnicas de Diagnóstico Molecular , ARN Viral/líquido cefalorraquídeo
15.
Virol J ; 12: 101, 2015 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-26141063

RESUMEN

BACKGROUND: In Korea, every vaccine lot is tested by the National Center for Lot Release (NCLR) in accordance with the national lot release procedures to ensure the safety and efficacy of vaccines. These quality tests examine the virus content in varicella vaccines via plaque assays (either the agar overlay method [AOM] or plaque staining method [PSM]), according to the procedures suggested by the Korean Reference Material for the Varicella Vaccine (KRMVV) or the manufacturer's standard in-house protocol. AIM: To standardize the virus content tests, viral titers in the KRMVV were measured using the PSM at four participating laboratories in a collaborative study. With the aim of developing a standardized method using the KRMVV as a positive control, we compared the ability of the two test methods, AOM and PSM, to accurately and reproducibly determine the virus content of two commercial varicella vaccines. RESULTS: The results showed that the standardized method (PSM) was more suitable for quality control analysis of the varicella vaccine. CONCLUSION: Use of a standardized method (PSM) according to the Korean reference material will improve the reliability and objectivity of lot release testing.


Asunto(s)
Vacuna contra la Varicela/inmunología , Tecnología Farmacéutica/métodos , Tecnología Farmacéutica/normas , Carga Viral/métodos , Carga Viral/normas , Humanos , Reproducibilidad de los Resultados , República de Corea , Ensayo de Placa Viral/métodos , Ensayo de Placa Viral/normas
16.
J Nat Prod ; 78(12): 2983-93, 2015 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-26595875

RESUMEN

The antiproliferative and antitumor activities of americanin A (1), a neolignan isolated from the seeds of Phytolacca americana, were investigated in human colon cancer cells. Compound 1 inhibited the proliferation of HCT116 human colon cancer cells both in vitro and in vivo. The induction of G2/M cell-cycle arrest by 1 was concomitant with regulation of the ataxia telangiectasia-mutated/ATM and Rad3-related (ATM/ATR) signaling pathway. Treatment with 1 activated ATM and ATR, initiating the subsequent signal transduction cascades that include checkpoint kinase 1 (Chk1), checkpoint kinase 2 (Chk2), and tumor suppressor p53. Another line of evidence underlined the significance of 1 in regulation of the S phase kinase-associated protein 2 (Skp2)-p27 axis. Compound 1 targeted selectively Skp2 for degradation and thereby stabilized p27. Therefore, compound 1 suppressed the activity of cyclin B1 and its partner cell division cycle 2 (cdc2) to prevent entry into mitosis. Furthermore, prolonged treatment with 1 induced apoptosis by producing excessive reactive oxygen species. The intraperitoneal administration of 1 inhibited the growth of HCT116 tumor xenografts in nude mice without any overt toxicity. Modulation of the ATM/ATR signaling pathway and the Skp2-p27 axis might be plausible mechanisms of action for the antiproliferative and antitumor activities of 1 in human colon cancer cells.


Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Dioxinas/aislamiento & purificación , Dioxinas/farmacología , Phytolacca americana/química , Animales , Antineoplásicos Fitogénicos/química , Apoptosis , Proteína Quinasa CDC2/metabolismo , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1) , Quinasa de Punto de Control 2/metabolismo , Neoplasias del Colon , Dioxinas/química , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Células HCT116 , Humanos , Ratones , Ratones Desnudos , Estructura Molecular , Proteínas Quinasas/metabolismo , Semillas/química , Transducción de Señal , Proteína p53 Supresora de Tumor/metabolismo
17.
Mar Drugs ; 13(11): 6962-76, 2015 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-26610526

RESUMEN

Hypoxia inducible factor-1α (HIF-1α) is an essential regulator of the cellular response to low oxygen concentrations, activating a broad range of genes that provide adaptive responses to oxygen deprivation. HIF-1α is overexpressed in various cancers and therefore represents a considerable chemotherapeutic target. Salternamide A (SA), a novel small molecule that is isolated from a halophilic Streptomyces sp., is a potent cytotoxic agent against a variety of human cancer cell lines. However, the mechanisms by which SA inhibits tumor growth remain to be elucidated. In the present study, we demonstrate that SA efficiently inhibits the hypoxia-induced accumulation of HIF-1α in a time- and concentration-dependent manner in various human cancer cells. In addition, SA suppresses the upstream signaling of HIF-1α, such as PI3K/Akt/mTOR, p42/p44 MAPK, and STAT3 signaling under hypoxic conditions. Furthermore, we found that SA induces cell death by stimulating G2/M cell cycle arrest and apoptosis in human colorectal cancer cells. Taken together, SA was identified as a novel small molecule HIF-1α inhibitor from marine natural products and is potentially a leading candidate in the development of anticancer agents.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Polienos/farmacología , Alcamidas Poliinsaturadas/farmacología , Antineoplásicos/administración & dosificación , Antineoplásicos/aislamiento & purificación , Apoptosis/efectos de los fármacos , Hipoxia de la Célula , Línea Celular Tumoral , Neoplasias Colorrectales/patología , Relación Dosis-Respuesta a Droga , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Humanos , Puntos de Control de la Fase M del Ciclo Celular/efectos de los fármacos , Polienos/administración & dosificación , Polienos/aislamiento & purificación , Alcamidas Poliinsaturadas/administración & dosificación , Alcamidas Poliinsaturadas/aislamiento & purificación , Transducción de Señal/efectos de los fármacos , Streptomyces/metabolismo , Factores de Tiempo
18.
Noise Health ; 17(75): 57-82, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25774609

RESUMEN

The mandate of the International Commission on Biological Effects of Noise (ICBEN) is to promote a high level of scientific research concerning all aspects of noise-induced effects on human beings and animals. In this review, ICBEN team chairs and co-chairs summarize relevant findings, publications, developments, and policies related to the biological effects of noise, with a focus on the period 2011-2014 and for the following topics: Noise-induced hearing loss; nonauditory effects of noise; effects of noise on performance and behavior; effects of noise on sleep; community response to noise; and interactions with other agents and contextual factors. Occupational settings and transport have been identified as the most prominent sources of noise that affect health. These reviews demonstrate that noise is a prevalent and often underestimated threat for both auditory and nonauditory health and that strategies for the prevention of noise and its associated negative health consequences are needed to promote public health.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Pérdida Auditiva Provocada por Ruido/etiología , Ruido/efectos adversos , Salud Pública , Trastornos del Sueño-Vigilia/etiología , Acúfeno/etiología , Humanos , Ruido en el Ambiente de Trabajo/efectos adversos , Ruido en el Ambiente de Trabajo/estadística & datos numéricos , Ruido del Transporte/efectos adversos , Ruido del Transporte/estadística & datos numéricos , Desempeño Psicomotor
19.
J Nat Prod ; 77(4): 917-24, 2014 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-24689881

RESUMEN

The anti-inflammatory activity of handelin (1), a guaianolide dimer from Chrysanthemum boreale flowers, was evaluated in vivo, and the effects on mediators nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), and interleukin-1ß (IL-1ß) and the nuclear factor-κB (NF-κB) and ERK/JNK signaling pathways were investigated in vitro. Compound 1 inhibited lipopolysaccharide (LPS)-induced production of NO and PGE2 in cultured mouse macrophage RAW 264.7 cells. The suppression of NO and PGE2 production by 1 was correlated with the downregulation of mRNA and protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Compound 1 also suppressed the induction of pro-inflammatory cytokines TNF-α and IL-1ß in LPS-stimulated RAW 264.7 cells. To further clarify the transcriptional regulatory pathway in the expression of iNOS and COX-2 by 1, the role of NF-κB was determined in RAW 264.7 cells. Compound 1 inhibits the binding activity of NF-κB into the nuclear proteins. The transcriptional activity of NF-κB stimulated with LPS was also suppressed by 1, which coincided with the inhibition of IκB degradation. Compound 1 also suppressed the activation of mitogen-activated protein kinases, including ERK and JNK signaling. In addition, the LPS-stimulated upregulation of miRNA-155 expression was suppressed by 1. The oral administration of 1 inhibited acute inflammation in carrageenan-induced paw and 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced ear edema models. The serum level of IL-1ß was also inhibited by 1 in a carrageenan-induced paw edema model. These findings suggest that the suppression of NF-κB activation and pro-inflammatory cytokine production may be a plausible mechanism of action for the anti-inflammatory activity of handelin.


Asunto(s)
Antiinflamatorios/farmacología , Chrysanthemum/química , Citocinas/metabolismo , Proteínas I-kappa B/metabolismo , FN-kappa B/efectos de los fármacos , Terpenos/farmacología , Animales , Antiinflamatorios/química , Ciclooxigenasa 2 , Dinoprostona/metabolismo , Regulación hacia Abajo , Edema/inducido químicamente , Edema/tratamiento farmacológico , Proteínas I-kappa B/efectos de los fármacos , Interleucina-1beta/efectos de los fármacos , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Ratones , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Modelos Animales , Estructura Molecular , Inhibidor NF-kappaB alfa , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo II/metabolismo , Fitoterapia , Transducción de Señal/efectos de los fármacos , Terpenos/química , Factor de Necrosis Tumoral alfa/efectos de los fármacos
20.
Chem Biodivers ; 11(5): 749-59, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24827684

RESUMEN

Anemarrhena asphodeloides is widely used in traditional Chinese medicine, and is known to possess antidiabetic and anti-inflammatory properties. Because inducible nitric oxide synthase (iNOS) plays an important role in inflammation, we investigated the inhibitory effects of two known phenolic compounds, nyasol (1) and broussonin A (2), from A. asphodeloides, on iNOS and its plausible mechanism of action. Compounds 1 and 2 exhibited inhibitory effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. Compounds 1 and 2 also suppressed the expressions of iNOS protein and mRNA. Moreover, compounds 1 and 2 suppressed the expression of inflammatory cytokines such as interleukin-1ß (IL-1ß) and interferon-ß (IFN-ß). They also inhibited the transcriptional activity of NF-κB and degradation of IκB-α, as well as the activation of Akt and ERK in LPS-stimulated RAW 264.7 cells. In in vivo animal model, compounds 1 and 2 significantly inhibited TPA-induced mouse ear edema. These results suggest that 1 and 2 suppress LPS-stimulated iNOS expression at the transcriptional level through modulating NF-κB and down-regulation of the Akt and ERK signaling pathways. Taken together, these findings indicate that the suppressive effects of 1 and 2 on iNOS expression might provide one possible mechanism for their anti-inflammatory activities.


Asunto(s)
Anemarrhena/química , Antiinflamatorios/farmacología , Proteínas I-kappa B/genética , Lignanos/farmacología , Macrófagos/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo II/genética , Fenoles/farmacología , Animales , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/uso terapéutico , Línea Celular , Regulación hacia Abajo/efectos de los fármacos , Edema/inducido químicamente , Edema/tratamiento farmacológico , Proteínas I-kappa B/inmunología , Lignanos/aislamiento & purificación , Lignanos/uso terapéutico , Lipopolisacáridos/inmunología , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Inhibidor NF-kappaB alfa , Óxido Nítrico/inmunología , Óxido Nítrico Sintasa de Tipo II/inmunología , Fenoles/aislamiento & purificación , Fenoles/uso terapéutico , Activación Transcripcional/efectos de los fármacos
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