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1.
Dev Biol ; 458(1): 52-63, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31639337

RESUMEN

The central nervous system of the Ciona larva contains only 177 neurons. The precise regulation of neuron subtype-specific morphogenesis and differentiation observed during the formation of this minimal connectome offers a unique opportunity to dissect gene regulatory networks underlying chordate neurodevelopment. Here we compare the transcriptomes of two very distinct neuron types in the hindbrain/spinal cord homolog of Ciona, the Motor Ganglion (MG): the Descending decussating neuron (ddN, proposed homolog of Mauthner Cells in vertebrates) and the MG Interneuron 2 (MGIN2). Both types are invariantly represented by a single bilaterally symmetric left/right pair of cells in every larva. Supernumerary ddNs and MGIN2s were generated in synchronized embryos and isolated by fluorescence-activated cell sorting for transcriptome profiling. Differential gene expression analysis revealed ddN- and MGIN2-specific enrichment of a wide range of genes, including many encoding potential "effectors" of subtype-specific morphological and functional traits. More specifically, we identified the upregulation of centrosome-associated, microtubule-stabilizing/bundling proteins and extracellular guidance cues part of a single intrinsic regulatory program that might underlie the unique polarization of the ddNs, the only descending MG neurons that cross the midline. Consistent with our predictions, CRISPR/Cas9-mediated, tissue-specific elimination of two such candidate effectors, Efcab6-related and Netrin1, impaired ddN polarized axon outgrowth across the midline.


Asunto(s)
Ciona intestinalis/genética , Ganglios de Invertebrados/citología , Regulación del Desarrollo de la Expresión Génica , Neuronas/clasificación , Animales , Orientación del Axón/fisiología , Sistemas CRISPR-Cas , Proteínas de Unión al Calcio/biosíntesis , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/fisiología , Sistema Nervioso Central/citología , Centrosoma/fisiología , Ciona intestinalis/citología , Ciona intestinalis/embriología , Ciona intestinalis/crecimiento & desarrollo , Conectoma , Embrión no Mamífero , Ganglios de Invertebrados/crecimiento & desarrollo , Edición Génica , Interneuronas/fisiología , Interneuronas/ultraestructura , Larva , Microtúbulos/fisiología , Neuronas Motoras/fisiología , Proteínas del Tejido Nervioso/biosíntesis , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/fisiología , Netrina-1/biosíntesis , Netrina-1/genética , Netrina-1/fisiología , Neurogénesis , Neuronas/fisiología , Neuronas/ultraestructura , Proteínas Represoras/biosíntesis , Proteínas Represoras/genética , Proteínas Represoras/fisiología , Transcriptoma
2.
Bioorg Med Chem Lett ; 29(3): 400-405, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30594431

RESUMEN

To increase the contents of medicinally effective ginsenosides, we used high-temperature and high-pressure thermal processing of ginseng by exposing it to microwave irradiation. To determine the anti-melanoma effect, the malignant melanoma SK-MEL-2 cell line was treated with an extract of microwave-irradiated ginseng. Microwave irradiation caused changes in the ginsenoside contents: the amounts of ginsenosides Rg1, Re, Rb1, Rb2, Rc, and Rd were disappeared, while those of less polar ginsenosides, such as Rg3, Rg5, and Rk1, were increased. In particular, the contents of Rk1 and Rg5 markedly increased. Melanoma cells treated with the microwave-irradiated ginseng extract showed markedly increased cell death. The results indicate that the microwave-irradiated ginseng extract induced melanoma cell death via the apoptotic pathway and that the cytotoxic effect of the microwave-irradiated ginseng extract is attributable to the increased contents of specific ginsenosides.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Ginsenósidos/farmacología , Melanoma/tratamiento farmacológico , Microondas , Extractos Vegetales/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Ginsenósidos/química , Ginsenósidos/aislamiento & purificación , Glicosilación , Humanos , Melanoma/patología , Estructura Molecular , Panax/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Relación Estructura-Actividad
3.
Nucleic Acids Res ; 42(13): 8486-99, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24981510

RESUMEN

In Saccharomyces cerevisiae, the stability of highly repetitive rDNA array is maintained through transcriptional silencing. Recently, a ß-1,3-glucanosyltransferase Gas1 has been shown to play a significant role in the regulation of transcriptional silencing in S. cerevisiae. Here, we show that the gas1Δ mutation increases rDNA silencing in a Sir2-dependent manner. Remarkably, the gas1Δ mutation induces nuclear localization of Msn2/4 and stimulates the expression of PNC1, a gene encoding a nicotinamidase that functions as a Sir2 activator. The lack of enzymatic activity of Gas1 or treatment with a cell wall-damaging agent, Congo red, exhibits effects similar to those of the gas1Δ mutation. Furthermore, the loss of Gas1 or Congo red treatment lowers the cAMP-dependent protein kinase (PKA) activity in a cell wall integrity MAP kinase Slt2-dependent manner. Collectively, our results suggest that the dysfunction of Gas1 plays a positive role in the maintenance of rDNA integrity by decreasing PKA activity and inducing the accumulation of Msn2/4 in the nucleus. It seems that nuclear-localized Msn2/4 stimulate the expression of Pnc1, thereby enhancing the association of Sir2 with rDNA and promoting rDNA stability.


Asunto(s)
ADN Ribosómico , Regulación Fúngica de la Expresión Génica , Silenciador del Gen , Glucano Endo-1,3-beta-D-Glucosidasa/fisiología , Glicoproteínas de Membrana/fisiología , Proteínas de Saccharomyces cerevisiae/fisiología , Proteínas Reguladoras de Información Silente de Saccharomyces cerevisiae/metabolismo , Sirtuina 2/metabolismo , Rojo Congo , Proteínas de Unión al ADN/metabolismo , Eliminación de Gen , Glucano Endo-1,3-beta-D-Glucosidasa/genética , Glucano Endo-1,3-beta-D-Glucosidasa/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Nicotinamidasa/biosíntesis , Saccharomyces cerevisiae/enzimología , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/biosíntesis , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/metabolismo
4.
Environ Sci Technol ; 48(24): 14543-8, 2014 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-25396409

RESUMEN

Catalytic CO oxidation was activated at low temperature by injecting O3 as an additive. It was empirically confirmed that CO removal rate was dramatically enhanced by supplying a small amount of O3, and the reaction temperature was almost half that required for CO oxidation when using a catalyst only. By optimizing the concentration of O3, catalytic CO oxidation could be achieved within 1 min at low operational temperature. The removal rate of CO was sensitive to the concentration of O3, and a deduced reaction mechanism is discussed to explain how catalytic CO oxidation is activated but subsequently deactivated at higher O3 concentration. Moreover, the presence of C3H8 and C3H6 were considered to evaluate the effects of each gas on the enhancement of CO removal rate by O3. Finally, the rate of CO removal was evaluated with increasing O3 concentration for practical applications such as the cold-start problem in automobile engines.


Asunto(s)
Monóxido de Carbono/aislamiento & purificación , Ozono/química , Catálisis , Diseño de Equipo , Hidrocarburos/química , Oxidación-Reducción , Platino (Metal) , Temperatura , Emisiones de Vehículos
5.
Environ Sci Technol ; 47(19): 10964-70, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24032692

RESUMEN

Stronger regulations on nitrogen oxide (NOx) production have recently promoted the creation of a diverse array of technologies for NOx reduction, particularly within the combustion process, where reduction is least expensive. In this paper, we discuss a new combustion technology that can reduce NOx emissions within industrial burners to single-digit parts per million levels without employing exhaust gas recirculation or other NOx reduction mechanisms. This new technology uses a simple modification of commercial burners, such that they are able to perform plasma-assisted staged combustion without altering the outer configuration of the commercial reference burner. We embedded the first-stage combustor within the head of the commercial reference burner, where it operated as a reformer that could host a partial oxidation process, producing hydrogen-rich reformate or synthesis gas product. The resulting hydrogen-rich flow then ignited and stabilized the combustion flame apart from the burner rim. Ultimately, the enhanced mixing and removal of hot spots with a widened flame area acted as the main mechanisms of NOx reduction. Because this plasma burner acted as a low NOx burner and was able to reduce NOx by more than half compared to the commercial reference burner, this methodology offers important cost-effective possibilities for NOx reduction in industrial applications.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/prevención & control , Óxidos de Nitrógeno/análisis , Administración de Residuos/métodos , Contaminantes Atmosféricos/química , Dióxido de Carbono/química , Monóxido de Carbono/análisis , Monóxido de Carbono/química , Calor , Hidrógeno/química , Residuos Industriales , Óxidos de Nitrógeno/química , Administración de Residuos/instrumentación
6.
Food Sci Anim Resour ; 43(4): 553-562, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37483996

RESUMEN

With an increase in meat consumption, the need to measure the weight of each primal cut of pork has increased. Recently, automation devices have been used to measure the weight of each primal cut of pork. The objective of this study was to investigate the accuracy of VCS2000, one of the non-invasive pig carcass analyzers. Production levels of 7 primal cuts of 50 pigs were measured with VCS2000. Average error rates between dissected value for each primal cut and VCS2000 measurement values of ham, shoulder picnic, belly, loin, and shoulder blade were around 5%. Average error rates for spare rib and tenderloin were about 10%. Correlation coefficients between the dissected value and the VCS2000 measured value for ham, shoulder picnic, loin, belly, and shoulder blade were high at 0.66-0.83. Correlation coefficients of spare rib and tenderloin were low at 0.35 and 0.47. Coefficient of determination of the VCS2000 measured value for each primal cut by regression analysis was 0.77 or more for ham, shoulder picnic, loin, and shoulder blade and 0.63 for belly. Coefficients of determination for spare rib and tenderloin were low at 0.40 and 0.27. In addition, the coefficient of determination of VCS2000 for each primal cut was higher than that of the dissected value for all primal cuts. In conclusion, pig carcass analysis using the VCS2000 has a high reliability for pork cuts with high production levels, but a relatively low reliability for pork cuts with low production levels and high fat levels.

7.
Front Cell Dev Biol ; 10: 999511, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36172287

RESUMEN

Pax3/7 factors play numerous roles in the development of the dorsal nervous system of vertebrates. From specifying neural crest at the neural plate borders, to regulating neural tube closure and patterning of the resulting neural tube. However, it is unclear which of these roles are conserved in non-vertebrate chordates. Here we investigate the expression and function of Pax3/7 in the model tunicate Ciona. Pax3/7 is expressed in neural plate border cells during neurulation, and in central nervous system progenitors shortly after neural tube closure. We find that separate cis-regulatory elements control the expression in these two distinct lineages. Using CRISPR/Cas9-mediated mutagenesis, we knocked out Pax3/7 in F0 embryos specifically in these two separate territories. Pax3/7 knockout in the neural plate borders resulted in neural tube closure defects, suggesting an ancient role for Pax3/7 in this chordate-specific process. Furthermore, knocking out Pax3/7 in the neural impaired Motor Ganglion neuron specification, confirming a conserved role for this gene in patterning the neural tube as well. Taken together, these results suggests that key functions of Pax3/7 in neural tube development are evolutionarily ancient, dating back at least to the last common ancestor of vertebrates and tunicates.

8.
Sci Adv ; 8(35): eadd2696, 2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36054355

RESUMEN

Vertebrate myoblast fusion allows for multinucleated muscle fibers to compound the size and strength of mononucleated cells, but the evolution of this important process is unknown. We investigated the evolutionary origins and function of membrane-coalescing agents Myomaker and Myomixer in various groups of chordates. Here, we report that Myomaker likely arose through gene duplication in the last common ancestor of tunicates and vertebrates, while Myomixer appears to have evolved de novo in early vertebrates. Functional tests revealed a complex evolutionary history of myoblast fusion. A prevertebrate phase of muscle multinucleation driven by Myomaker was followed by the later emergence of Myomixer that enables the highly efficient fusion system of vertebrates. Evolutionary comparisons between vertebrate and nonvertebrate Myomaker revealed key structural and mechanistic insights into myoblast fusion. Thus, our findings suggest an evolutionary model of chordate fusogens and illustrate how new genes shape the emergence of novel morphogenetic traits and mechanisms.

9.
Front Cell Dev Biol ; 8: 477, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32656209

RESUMEN

Neurogenesis is a complex sequence of cellular processes and behaviors driven by the coordinated expression of conserved effectors. The bipolar tail neurons (BTNs) of Ciona develop according to a highly dynamic, yet highly stereotyped developmental program and thus could serve as an accessible model system for neurogenesis, including underlying cell behaviors like neuronal delamination, migration, and polarized axon outgrowth. Here we investigate both the upstream events that shape BTN neurogenesis through spatiotemporal regulation of the conserved proneural factor Neurog, spatiotemporal, and the gene expression profile of differentiating BTNs downstream of Neurog activity. We show that, although early FGF signaling is required for Neurog expression and BTN specification, Fgf8/17/18 is expressed in tail tip cells at later stages and suppresses sustained Neurog expression in the anterior BTN (aBTN) lineage, such that only one cell (the one furthest from the source of Fgf8/17/18) maintains Neurog expression and becomes a neuron. Curiously, Fgf8/17/18 might not affect neurogenesis of the posterior BTNs (pBTNs), which are in direct contact with the Fgf8/17/18-expressing cells. Finally, to profile gene expression associated with BTN neurogenesis we performed RNAseq of isolated BTN lineage cells in which BTN neurogenesis was enhanced or suppressed by perturbing Neurog function. This allowed us to identify several candidate genes that might play conserved roles in neurogenesis and neuronal migration in other animals, including mammals.

10.
Environ Int ; 145: 106113, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32947162

RESUMEN

Activated carbon has been extensively utilized to adsorb pollutants generated by industrial activities. There have been many attempts to efficiently produce activated carbon from spent coffee grounds in the field of environmental technology. In this study, the feasibility of the novel production of activated carbon from coffee ground waste using a plasma jet was evaluated. A rotating gliding arc generator was designed that used an N2 plasma jet for the carbonization process and a CO2 plasma jet for the activation process. It was confirmed that the coffee ground waste could be carbonized and activated by the two plasma jets in the same reactor. The characteristics of the surface morphologies of the activated carbon samples varied depending on the plasma treatment conditions, such as the electric power of the plasma jet and the treatment time. The results implied that the adsorption capacity of the activated carbon could be optimized by regulating the pore size and distribution based on the plasma treatment conditions with regard to the molecular size of the target adsorbate.


Asunto(s)
Carbón Orgánico , Café , Adsorción , Plasma
11.
RSC Adv ; 9(56): 32403-32413, 2019 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-35529722

RESUMEN

The proliferation of natural gas production had led to increased utilization of methane as a raw material for chemicals. The most significant bottleneck in this process is the high activation energy of methane. This paper reports the direct conversion of methane to acetylene in a novel rotating arc driven by AC electrical power. By feeding a sufficiently high concentration of CH4 (greater than 43%) diluted in H2 (the discharge gas) through the arc column, a low specific energy requirement (SER) of 10.2 kW h kg-1 C2H2 was achieved. The use of hydrogen as the discharge gas strongly suppressed soot formation during the methane conversion process under high methane concentration conditions, resulting in a carbon balance of greater than 95% and a C2H2 selectivity of greater than 90% while maintaining a methane conversion rate of greater than 70%, depending on the conditions. The novel rotating arc enabled the elongation of the arc column itself, which controlled heat loss and improved the energy use for reaction. The ability to control the arc length based on low-current type arc generation has additional benefits for reaction enhancement. These results demonstrate that arc control, optimization of the reaction conditions, and a full understanding of reaction pathway are viable means for the energy-efficient direct conversion of methane to acetylene.

12.
J Healthc Eng ; 2017: 9342789, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29065668

RESUMEN

The main purpose of this study was to investigate the effect of arch support insoles on uphill and downhill walking of persons with flatfoot. Sixteen healthy college students with flatfoot were recruited in this study. Their heart rate, peak oxygen uptake (VO2), and median frequency (MDF) of surface electromyogram were recorded and analyzed. Nonparametric Wilcoxon signed-rank test was used for statistical analysis. The main results were as follows: (a) peak VO2 significantly decreased with arch support insoles compared with flat insoles during uphill and downhill walking (arch support insole versus flat insole: uphill walking, 20.7 ± 3.6 versus 31.6 ± 5.5; downhill walking, 10.9 ± 2.3 versus 16.9 ± 4.2); (b) arch support insoles could reduce the fatigue of the rectus femoris muscle during downhill walking (MDF slope of arch support insole: 0.03 ± 1.17, flat insole: -6.56 ± 23.07); (c) insole hardness would increase not only the physical sensory input but also the fatigue of lower-limb muscles particularly for the rectus femoris muscle (MDF slope of arch support insole: -1.90 ± 1.60, flat insole: -0.83 ± 1.10) in persons with flatfoot during uphill walking. The research results show that arch support insoles could effectively be applied to persons with flatfoot to aid them during uphill and downhill walking.


Asunto(s)
Pie Plano/terapia , Ortesis del Pié , Caminata , Humanos , Adulto Joven
13.
Leuk Res ; 61: 96-103, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28938223

RESUMEN

Mutational profiles of 153 Korean myelodysplastic syndrome (MDS) patients were investigated. Sequencing of 87 genes presented similar mutational profiles in Korean MDS patients compared with previous reports. The most frequently mutated genes were ASXL1 (22.9%), U2AF1 (16.3%), TP53 (13.7%), RUNX1 (10.5%), TET2 (10.5%), DNMT3A (8.5%), and SRSF2 (8.5%). The U2AF1 mutation frequency was higher, with different frequencies in the mutated sites of U2AF1 (S34Y, 6/25; S34F, 11/25; and Q157P 8/25). The U2AF1 S34Y mutation was strongly associated with isolated trisomy 8 (5/6, 83%) and was characterized by a younger age of MDS onset (median, 39 years). The S34F mutation was associated with trisomy 8 (6/11, 55%) and del(20q) (3/11, 27%). Data from 10 literatures (total 3460 patients) of 229 U2AF1-mutated cases revealed a significant association between the S34Y and trisomy 8 in Asians (P=0.0001), but not in Caucasians (P=0.080). We infer that U2AF1 S34 mutations characterize a distinct subgroup of MDS: younger age of onset and differential associations with particular cytogenetic aberrations depending on specific mutations [S34Y to +8; S34F to +8 and del(20q)]. The impact and causal relationship between U2AF1 S34 and trisomy 8 need to be elucidated, which might contribute to design of tailored treatments.


Asunto(s)
Síndromes Mielodisplásicos/genética , Factor de Empalme U2AF/genética , Trisomía/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Pueblo Asiatico/genética , Cromosomas Humanos Par 8/genética , Análisis Mutacional de ADN , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Hibridación Fluorescente in Situ , Estimación de Kaplan-Meier , Corea (Geográfico) , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Población Blanca/genética , Adulto Joven
14.
J Hematol Oncol ; 9(1): 62, 2016 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-27465399

RESUMEN

BACKGROUND: Telomere erosion can lead to genomic instability and cancer progression. It has been suggested that the shortest telomere, not the average telomere length (TL), is critical for cell viability. Some studies have shown shorter TL in myelodysplastic syndrome (MDS) patients but the critically short telomeres, the variability of TL within individual patient has not been evaluated. Thus, we aimed to investigate the TL of MDS patients and assessed the association of TL with recurrent genetic mutations in MDS. METHODS: We measured the TL of bone marrow nucleated cells for diagnostic samples at a single-cell level by quantitative fluorescence in situ hybridization (Q-FISH) for 58 MDS patients and analyzed the minimum, median, average, standard deviation, average of the 0th to 10th percentile TL within a patient, and the proportion of cells with TL that is shorter than the lowest 10th percentile of the normal control (NC). The correlations of TL to clinical parameters, cytogenetic results, and genetic mutations were assessed. RESULTS: MDS patients showed eroded telomeres and narrow distribution compared to the NC (P < 0.001, P = 0.018, respectively). Patients with mutation showed significantly lesser cells with short TL, below the lowest 10th percentile of the NC (P = 0.017), but no differences in TL were found according to mutations/cytogenetic abnormalities except for CSF3R mutation. However, those patients with a high percentage (≥80 %) of cells with short TL showed poorer overall survival (P = 0.021), and this was an independent prognostic factor, along with TP53, U2AF1 mutation, and high BM blast count (P = 0.044, 0.001, 0.004, 0.012, respectively). CONCLUSIONS: The shortest TL, which determines the fate of the cell, was significantly shorter, and higher burden of cells with short TL were found in MDS, which correlated with poor survival, suggesting the need to measure TL in single cells by Q-FISH.


Asunto(s)
Mutación , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/patología , Telómero/patología , Adolescente , Adulto , Anciano , Células de la Médula Ósea , Aberraciones Cromosómicas , Femenino , Inestabilidad Genómica , Humanos , Hibridación Fluorescente in Situ , Masculino , Persona de Mediana Edad , Tasa de Supervivencia , Acortamiento del Telómero , Adulto Joven
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