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1.
Cell ; 173(2): 430-442.e17, 2018 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-29606353

RESUMO

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.


Assuntos
Proteínas de Transporte/metabolismo , Hemoglobina Fetal/genética , Proteínas Nucleares/metabolismo , Sequência de Bases , Sítios de Ligação , Proteínas de Transporte/genética , Linhagem Celular , Cromatina/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Células Eritroides/citologia , Células Eritroides/metabolismo , Edição de Genes , Humanos , Proteínas Nucleares/genética , Regiões Promotoras Genéticas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Repressoras , Dedos de Zinco/genética , Globinas beta/genética , Talassemia beta/genética , Talassemia beta/patologia , gama-Globinas/genética
2.
Sensors (Basel) ; 21(24)2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34960429

RESUMO

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.


Assuntos
Algoritmos , Máquina de Vetores de Suporte , Computadores , Meios de Transporte
3.
Pharmacol Res ; 160: 105147, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32814167

RESUMO

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.


Assuntos
Antineoplásicos/farmacologia , Derivados de Benzeno/farmacologia , Carcinoma Pulmonar de Células não Pequenas/prevenção & controle , Neoplasias Pulmonares/prevenção & controle , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Morfolinas/farmacologia , Metástase Neoplásica/prevenção & controle , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Quinazolinas/farmacologia , Receptores da Família Eph/efeitos dos fármacos , Receptores da Família Eph/metabolismo , Sulfonamidas/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteína Oncogênica v-akt/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Molecules ; 25(3)2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31979361

RESUMO

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.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Furocumarinas/farmacologia , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Angelica/química , Protocolos de Quimioterapia Combinada Antineoplásica , Proteína Quinase CDC2/metabolismo , Carcinoma Hepatocelular/metabolismo , Proliferação de Células/efeitos dos fármacos , Quinase 1 do Ponto de Checagem/metabolismo , Ciclina B1/metabolismo , Ciclina E/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Sinergismo Farmacológico , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fosfatases cdc25/metabolismo , Gencitabina
5.
Mediators Inflamm ; 2019: 7651470, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31182933

RESUMO

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.


Assuntos
Anti-Inflamatórios/uso terapêutico , Estenose Espinal/tratamento farmacológico , Animais , Anti-Inflamatórios/química , Western Blotting , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Imuno-Histoquímica , Interleucina-1beta/metabolismo , Locomoção/fisiologia , Masculino , NF-kappa B/metabolismo , Ratos , Ratos Sprague-Dawley , Estenose Espinal/imunologia , Estenose Espinal/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
6.
J Dairy Sci ; 102(12): 10845-10849, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31629522

RESUMO

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.


Assuntos
Kefir/microbiologia , Probióticos/metabolismo , Saccharomyces cerevisiae/metabolismo , Acetobacter/isolamento & purificação , Animais , Fermentação , Kluyveromyces/isolamento & purificação , Lactobacillus/isolamento & purificação , Microbiota , RNA Ribossômico 16S , beta-Glucanas/análise
7.
Int J Mol Sci ; 20(24)2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31835356

RESUMO

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.


Assuntos
Materiais Biomiméticos/química , Matriz Extracelular/química , Nanofibras/química , Engenharia Tecidual , Alicerces Teciduais/química , Animais , Humanos , Medicina Regenerativa
8.
Int J Cancer ; 141(2): 220-230, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28240776

RESUMO

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.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Exossomos/metabolismo , MicroRNAs/genética , Neoplasias/genética , Animais , Antineoplásicos/uso terapêutico , Comunicação Celular , Exossomos/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Transdução de Sinais , Microambiente Tumoral
9.
Development ; 141(7): 1480-91, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24574008

RESUMO

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.


Assuntos
Vasos Sanguíneos/fisiologia , Comunicação Celular/genética , Ilhotas Pancreáticas/irrigação sanguínea , Ilhotas Pancreáticas/inervação , Neovascularização Fisiológica/fisiologia , Fator A de Crescimento do Endotélio Vascular/fisiologia , Animais , Vasos Sanguíneos/embriologia , Células Cultivadas , Embrião de Mamíferos , Endotélio Vascular/embriologia , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiologia , Feminino , Ilhotas Pancreáticas/embriologia , Camundongos , Camundongos Transgênicos , Fator A de Crescimento do Endotélio Vascular/genética
10.
Bioorg Med Chem ; 25(13): 3396-3405, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28478865

RESUMO

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.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Citocinas/antagonistas & inibidores , Lipopolissacarídeos/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico/antagonistas & inibidores , Ftalimidas/farmacologia , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Lipopolissacarídeos/farmacologia , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/metabolismo , Ftalimidas/síntese química , Ftalimidas/química , Células RAW 264.7 , Relação Estrutura-Atividade
11.
J Nat Prod ; 79(4): 1097-104, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-27064730

RESUMO

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.


Assuntos
Autofagia/efeitos dos fármacos , Liliaceae/química , Saponinas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose , Proteína Beclina-1 , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais , Células HCT116 , Humanos , Proteínas de Membrana , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Estrutura Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Saponinas/química , Saponinas/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos
12.
Molecules ; 21(12)2016 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-27999400

RESUMO

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.


Assuntos
Biofilmes , Cárie Dentária/prevenção & controle , Probióticos , Weissella/metabolismo , Fusobacterium/fisiologia , Peróxido de Hidrogênio/metabolismo , Lactobacillus/metabolismo , Muramidase/metabolismo , Streptococcus mutans/fisiologia , Compostos de Enxofre/metabolismo
13.
Korean J Physiol Pharmacol ; 20(4): 367-78, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27382353

RESUMO

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: 101, 2015 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-26141063

RESUMO

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.


Assuntos
Vacina contra Varicela/imunologia , Tecnologia Farmacêutica/métodos , Tecnologia Farmacêutica/normas , Carga Viral/métodos , Carga Viral/normas , Humanos , Reprodutibilidade dos Testes , República da Coreia , Ensaio de Placa Viral/métodos , Ensaio de Placa Viral/normas
15.
Virol J ; 12: 27, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25886579

RESUMO

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.


Assuntos
Infecções por Enterovirus/virologia , Enterovirus/isolamento & purificação , Meningite/virologia , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Enterovirus/genética , Infecções por Enterovirus/líquido cefalorraquidiano , Infecções por Enterovirus/diagnóstico , Humanos , Meningite/líquido cefalorraquidiano , Meningite/diagnóstico , Técnicas de Diagnóstico Molecular , RNA Viral/líquido cefalorraquidiano
16.
J Nat Prod ; 78(12): 2983-93, 2015 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-26595875

RESUMO

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.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Dioxinas/isolamento & purificação , Dioxinas/farmacologia , Phytolacca americana/química , Animais , Antineoplásicos Fitogênicos/química , Apoptose , Proteína Quinase CDC2/metabolismo , Quinase 1 do Ponto de Checagem , Quinase do Ponto de Checagem 2/metabolismo , Neoplasias do Colo , Dioxinas/química , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Células HCT116 , Humanos , Camundongos , Camundongos Nus , Estrutura Molecular , Proteínas Quinases/metabolismo , Sementes/química , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo
17.
Mar Drugs ; 13(11): 6962-76, 2015 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-26610526

RESUMO

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.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Polienos/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Antineoplásicos/administração & dosagem , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Hipóxia Celular , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Relação Dose-Resposta a Droga , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Polienos/administração & dosagem , Polienos/isolamento & purificação , Alcamidas Poli-Insaturadas/administração & dosagem , Alcamidas Poli-Insaturadas/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , Streptomyces/metabolismo , Fatores de Tempo
18.
Noise Health ; 17(75): 57-82, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25774609

RESUMO

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.


Assuntos
Doenças Cardiovasculares/epidemiologia , Perda Auditiva Provocada por Ruído/etiologia , Ruído/efeitos adversos , Saúde Pública , Transtornos do Sono-Vigília/etiologia , Zumbido/etiologia , Humanos , Ruído Ocupacional/efeitos adversos , Ruído Ocupacional/estatística & dados numéricos , Ruído dos Transportes/efeitos adversos , Ruído dos Transportes/estatística & dados numéricos , Desempenho Psicomotor
19.
J Nat Prod ; 77(4): 917-24, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24689881

RESUMO

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.


Assuntos
Anti-Inflamatórios/farmacologia , Chrysanthemum/química , Citocinas/metabolismo , Proteínas I-kappa B/metabolismo , NF-kappa B/efeitos dos fármacos , Terpenos/farmacologia , Animais , Anti-Inflamatórios/química , Ciclo-Oxigenase 2 , Dinoprostona/metabolismo , Regulação para Baixo , Edema/induzido quimicamente , Edema/tratamento farmacológico , Proteínas I-kappa B/efeitos dos fármacos , Interleucina-1beta/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Modelos Animais , Estrutura Molecular , Inibidor de NF-kappaB alfa , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/metabolismo , Fitoterapia , Transdução de Sinais/efeitos dos fármacos , Terpenos/química , Fator de Necrose Tumoral alfa/efeitos dos fármacos
20.
Chem Biodivers ; 11(5): 749-59, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24827684

RESUMO

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.


Assuntos
Anemarrhena/química , Anti-Inflamatórios/farmacologia , Proteínas I-kappa B/genética , Lignanas/farmacologia , Macrófagos/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/genética , Fenóis/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/uso terapêutico , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Edema/induzido quimicamente , Edema/tratamento farmacológico , Proteínas I-kappa B/imunologia , Lignanas/isolamento & purificação , Lignanas/uso terapêutico , Lipopolissacarídeos/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Inibidor de NF-kappaB alfa , Óxido Nítrico/imunologia , Óxido Nítrico Sintase Tipo II/imunologia , Fenóis/isolamento & purificação , Fenóis/uso terapêutico , Ativação Transcricional/efeitos dos fármacos
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