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1.
J Mech Behav Biomed Mater ; 122: 104680, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34271404

RESUMEN

Motion sensitive MR imaging techniques allow for the non-invasive evaluation of biological tissues by using different excitation schemes, including physiological/intrinsic motions caused by cardiac pulsation or respiration, and vibrations caused by an external actuator. The mechanical biomarkers extracted through these imaging techniques have been shown to hold diagnostic value for various neurological disorders and conditions. Amplified MRI (aMRI), a cardiac gated imaging technique, can help track and quantify low frequency intrinsic motion of the brain. As for high frequency actuation, the mechanical response of brain tissue can be measured by applying external high frequency actuation in combination with a motion sensitive MR imaging sequence called Magnetic Resonance Elastography (MRE). Due to the frequency-dependent behavior of brain mechanics, there is a need to develop brain phantom models that can mimic the broadband mechanical response of the brain in order to validate motion-sensitive MR imaging techniques. Here, we have designed a novel phantom test setup that enables both the low and high frequency responses of a brain-mimicking phantom to be captured, allowing for both aMRI and MRE imaging techniques to be applied on the same phantom model. This setup combines two different vibration sources: a pneumatic actuator, for low frequency/intrinsic motion (1 Hz) for use in aMRI, and a piezoelectric actuator for high frequency actuation (30-60 Hz) for use in MRE. Our results show that in MRE experiments performed from 30 Hz through 60 Hz, propagating shear waves attenuate faster at higher driving frequencies, consistent with results in the literature. Furthermore, actuator coupling has a substantial effect on wave amplitude, with weaker coupling causing lower amplitude wave field images, specifically shown in the top-surface shear loading configuration. For intrinsic actuation, our results indicate that aMRI linearly amplifies motion up to at least an amplification factor of 9 for instances of both visible and sub-voxel motion, validated by varying power levels of pneumatic actuation (40%-80% power) under MR, and through video analysis outside the MRI scanner room. While this investigation used a homogeneous brain-mimicking phantom, our setup can be used to study the mechanics of non-homogeneous phantom configurations with bio-interfaces in the future.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Humanos , Movimiento (Física) , Fantasmas de Imagen
2.
Med. intensiva (Madr., Ed. impr.) ; 43(1): 3-9, ene.-feb. 2019. tab, graf
Artículo en Inglés | IBECS | ID: ibc-181524

RESUMEN

Objective: Cognitive impairment after intensive care unit (ICU) admission is becoming increasingly recognized. High-dose deep sedation has been suggested to play an important role in the development of cognitive impairment. However, the impact of heavy sedation as a single cause in the development of cognitive impairment in ICU patients remains unclear. In this study we investigated whether a three-day deep sedation protocol could reduce cognitive function in mechanically ventilated non-critical patients. Design: A prospective observational study was carried out. Patients: A total of 17 surgical patients were studied. Intervention: None. Variables of interest: Cognitive function before and after ICU admission. Results: Thirty-one patients requiring three days of sedation after microvascular reconstruction were initially enrolled in the study. Sedation in the ICU was maintained with propofol and dexmedetomidine combined with fentanyl. Cognitive function was assessed using a battery of 6 neuropsychological tests two days before surgery and three weeks after surgery. Finally, a total of 17 patients were included in the analysis. Cognitive impairment (defined as a decline of >20% from the pre-admission cognitive evaluation scores in at least two of 6 tests) was observed in 5 of the 17 patients (29%). However, there were no significant differences between the pre- and post-admission cognitive evaluations in 6 tests. Conclusions: Middle-term cognitive function can be impaired in some patients subjected to deep sedation during several days following maxillary-mandibular oral surgery with microvascular reconstruction


Objetivo: Cada vez existe un mayor consenso sobre la afectación cognitiva tras el ingreso en la unidad de cuidados intensivos (UCI). Se ha sugerido que la sedación profunda con dosis elevada desempeña un papel importante en el desarrollo de la alteración cognitiva. Sin embargo, todavía existen dudas sobre el impacto de este tipo de sedación como causa única del desarrollo de alteraciones cognitivas en pacientes ingresados en la UCI. En este estudio, investigamos si la aplicación de un protocolo de sedación profunda durante 3 días disminuía la función cognitiva en pacientes no críticos bajo ventilación mecánica. Diseño: Se llevó a cabo un estudio observacional prospectivo. Pacientes: Se estudió a un total de 17 pacientes quirúrgicos. Intervenciones: Ninguna. Variables de interés: Función cognitiva antes y después del ingreso en la UCI. Resultados: En este estudio se incluyó inicialmente a 31 pacientes que requerían 3 días de sedación tras una reconstrucción microvascular. Se mantuvo la sedación en la UCI con propofol y dexmedetomidina en combinación con fentanilo. Se evaluó la función cognitiva mediante un grupo de 6 pruebas neurofisiológicas antes de la intervención y 3 días después de esta. Por último, se incluyó a un total de 17 pacientes en el análisis. Se observó alteración cognitiva (definida como una reducción>20% frente a las puntuaciones de la evaluación cognitiva previa al ingreso en al menos 2 de las 6 pruebas) en 5 de los 17 pacientes (29%). Sin embargo, no se observaron diferencias significativas entre las evaluaciones previas y posteriores al ingreso en 6 pruebas. Conclusiones: La función cognitiva a medio plazo puede verse afectada en algunos pacientes sometidos a sedación profunda durante varios días tras una cirugía oral maxilar-mandibular con reconstrucción microvascular


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Sedación Profunda/efectos adversos , Respiración Artificial , Procedimientos Quirúrgicos Orales , Cuidados Críticos , Disfunción Cognitiva/inducido químicamente , Estudios Prospectivos , Unidades de Cuidados Intensivos , Neurofisiología , Periodo Posoperatorio , Sedación Profunda/métodos , Cognición/efectos de los fármacos
3.
Med Intensiva (Engl Ed) ; 43(1): 3-9, 2019.
Artículo en Inglés, Español | MEDLINE | ID: mdl-29258778

RESUMEN

OBJECTIVE: Cognitive impairment after intensive care unit (ICU) admission is becoming increasingly recognized. High-dose deep sedation has been suggested to play an important role in the development of cognitive impairment. However, the impact of heavy sedation as a single cause in the development of cognitive impairment in ICU patients remains unclear. In this study we investigated whether a three-day deep sedation protocol could reduce cognitive function in mechanically ventilated non-critical patients. DESIGN: A prospective observational study was carried out. PATIENTS: A total of 17 surgical patients were studied. INTERVENTION: None. VARIABLES OF INTEREST: Cognitive function before and after ICU admission. RESULTS: Thirty-one patients requiring three days of sedation after microvascular reconstruction were initially enrolled in the study. Sedation in the ICU was maintained with propofol and dexmedetomidine combined with fentanyl. Cognitive function was assessed using a battery of 6 neuropsychological tests two days before surgery and three weeks after surgery. Finally, a total of 17 patients were included in the analysis. Cognitive impairment (defined as a decline of >20% from the pre-admission cognitive evaluation scores in at least two of 6 tests) was observed in 5 of the 17 patients (29%). However, there were no significant differences between the pre- and post-admission cognitive evaluations in 6 tests. CONCLUSIONS: Middle-term cognitive function can be impaired in some patients subjected to deep sedation during several days following maxillary-mandibular oral surgery with microvascular reconstruction.


Asunto(s)
Trastornos del Conocimiento/prevención & control , Cognición/efectos de los fármacos , Cuidados Críticos , Sedación Profunda/efectos adversos , Complicaciones Posoperatorias/prevención & control , Respiración Artificial , Anciano , Anciano de 80 o más Años , Protocolos Clínicos , Trastornos del Conocimiento/inducido químicamente , Dexmedetomidina , Neoplasias Faciales/cirugía , Femenino , Fentanilo , Humanos , Hipnóticos y Sedantes/administración & dosificación , Hipnóticos y Sedantes/efectos adversos , Unidades de Cuidados Intensivos , Masculino , Neoplasias Maxilares/cirugía , Microcirculación , Persona de Mediana Edad , Neoplasias de la Boca/cirugía , Pruebas Neuropsicológicas , Complicaciones Posoperatorias/inducido químicamente , Propofol , Estudios Prospectivos , Procedimientos de Cirugía Plástica , Factores de Tiempo
4.
Anim Genet ; 49(5): 461-463, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30109696

RESUMEN

Previously, a single nucleotide polymorphism (SNP) related to gait type was identified at position 22 999 655 of chromosome 23 in the coding region of DMRT3 (DMRT3:Ser301Ter) by showing that a cytosine (C) to adenine (A) mutation of this SNP induced pace in the Icelandic horse. We investigated the effect of DMRT3:Ser301Ter on the gait of Hokkaido Native Horses, a Japanese native breed, and examined genetic factors other than DMRT3 by exploring genome-wide SNPs related to gait determination. All animals exhibiting pace were AA for DMRT3:Ser301Ter, confirming the association of DMRT3:Ser301Ter with gait determination; however, 14.3% of the animals exhibiting trot also had AA for DMRT3:Ser301Ter, suggesting the presence of another factor(s) cooperatively working with DMRT3:Ser301Ter for gait determination. SNPs on chromosomes 13 and 23 were detected by genome-wide association analysis (false discovery rate <0.05), although SNPs on chromosome 23 were all located in the vicinity of DMRT3:Ser301Ter, confirming the association with DMRT3. A genome-wide association study targeting only animals with AA for DMRT3:Ser301Ter to examine genetic factors cooperatively working with DMRT3:Ser301Ter for gait determination suggested associations of 23 SNPs on six chromosomes. In a series of analyses of the effect of a maternal factor (dam's gait) on gait determination, the effect was suggested in comparison of the frequencies of exhibiting pace in gait checks in only two animal groups having dams with different DMRT3:Ser301Ter genotypes (P < 0.05), suggesting that the gait of the dam does not have a major effect on whether progeny homozygous for the DMRT3:Ser301Ter mutation will preferentially pace or trot.


Asunto(s)
Marcha , Caballos/clasificación , Caballos/genética , Herencia Materna , Factores de Transcripción/genética , Animales , Estudio de Asociación del Genoma Completo
5.
Nature ; 560(7720): 613-616, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30158605

RESUMEN

Galaxies in the early Universe that are bright at submillimetre wavelengths (submillimetre-bright galaxies) are forming stars at a rate roughly 1,000 times higher than the Milky Way. A large fraction of the new stars form in the central kiloparsec of the galaxy1-3, a region that is comparable in size to the massive, quiescent galaxies found at the peak of cosmic star-formation history4 and the cores of present-day giant elliptical galaxies. The physical and kinematic properties inside these compact starburst cores are poorly understood because probing them at relevant spatial scales requires extremely high angular resolution. Here we report observations with a linear resolution of 550 parsecs of gas and dust in an unlensed, submillimetre-bright galaxy at a redshift of z = 4.3, when the Universe was less than two billion years old. We resolve the spatial and kinematic structure of the molecular gas inside the heavily dust-obscured core and show that the underlying gas disk is clumpy and rotationally supported (that is, its rotation velocity is larger than the velocity dispersion). Our analysis of the molecular gas mass per unit area suggests that the starburst disk is gravitationally unstable, which implies that the self-gravity of the gas is stronger than the differential rotation of the disk and the internal pressure due to stellar-radiation feedback. As a result of the gravitational instability in the disk, the molecular gas would be consumed by star formation on a timescale of 100 million years, which is comparable to gas depletion times in merging starburst galaxies5.

6.
Phys Chem Chem Phys ; 18(9): 6683-90, 2016 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-26871617

RESUMEN

In this study, we present the high pressure spectroscopy of Y3Al2Ga3O12 (YAGG) and Y3Ga5O12 (YGG) ceramics doped with Ce(3+) and Cr(3+). We have found that high hydrostatic pressure recovers the Ce(3+) luminescence in YGG. The pressure-induced shifts of the ground state and the 5d1 excited state of Ce(3+) with respect to the conduction band edge were estimated. Our experimental data allowed us to also obtain the shifts of the conduction and valence band edges, and the ground state and the 5d1 state of Ce(3+) ions have been estimated with respect to the vacuum level. It has been shown that simple equivalence between the external hydrostatic pressure and intrinsic chemical pressure related to different compositions of the isostructural matrices does not exist in garnet lattices.

7.
Springerplus ; 5(1): 2109, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28066698

RESUMEN

BACKGROUND: Bovine Mx2 gene sequences were already reported, but further information about the gene properties is not yet available. The objective of the current study was to elucidate the structural properties of the bovine Mx2 gene mainly the promoter region and its possible functional role. If available, such information would help in assessing the functional properties of the gene, which was reported to confer antiviral action against recombinant VSV. RESULTS: Examinations on the bovine genomic BAC clone-confirmed to contain the Mx2 gene-revealed 883-bp sequences. A computer scan unequivocally identified a 788-bp promoter region containing a typical TATA box, three ISREs and other promoter-specific motifs. Comparative analysis of nine bovine genomic DNA samples showed 19 nucleotide substitutions suggesting the existence of five different genotypes in the promoter region. The water buffalo Mx2 promoter region was determined by using primers based on the bovine Mx2 promoter region disclosing 893-bp, with 56 substitutions, two insertions, 9 and 1 nt at two different sites. A functional analysis of the putative ISRE indicated that ISRE played a synergetic role in the activation of bovine Mx2 gene transcription. CONCLUSION: Bovine and water buffalo Mx2 promoter region was identified disclosing, the conserved ISRE, located in the proximal end of the promoter region like other members of the antiviral family, suggesting functional activity under interferon stimulation.

8.
Oncogene ; 33(36): 4485-95, 2014 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-24077287

RESUMEN

Epithelial splicing regulatory protein 1 (ESRP1) binds the FGFR-2 auxiliary cis-element ISE/ISS-3, located in the intron between exon IIIb and IIIc, and primarily promotes FGFR-2 IIIb expression. Here we assessed the role of ESRP1 in pancreatic ductal adenocarcinoma (PDAC). Immunohistochemical analysis was performed using anti-ESRP1, FGFR-2 IIIb and FGFR-2 IIIc antibodies in 123 PDAC cases. ESRP1 expression vector and small interference RNA (siRNA) targeting ESRP1 were transfected into human PDAC cells, and cell growth, migration and invasion were analyzed. In vivo heterotopic and orthotopic implantations using ESRP1 overexpression clones were performed and effects on pancreatic tumor volumes and hepatic and pulmonary metastases determined. ESRP1 immunoreactivity was strong in the nuclei of cancer cells in well-to-moderately differentiated PDACs but weak in poorly differentiated cancers. Well-to-moderately differentiated cancers also exhibited high FGFR-2 IIIb and low FGFR-2 IIIc expression, whereas this ratio was reversed in the poorly differentiated cancers. Increased ESRP1 expression was associated with longer survival in comparison with low ESRP1 expression, and PANC-1 cells engineered to express ESRP1 exhibited increased FGFR-2 IIIb expression and decreased migration and invasion in vitro, whereas ESRP1 siRNA-transfected KLM-1 cells exhibited increased FGFR-2 IIIc expression and increased cell growth, migration and invasion. In vivo, ESRP1-overexpressing clones formed significantly fewer liver metastases as compared with control clones. ESRP1 regulates the expression pattern of FGFR-2 isoforms, attenuates cell growth, migration, invasion and metastasis, and is a favorable prognostic factor in PDAC. Therefore, devising mechanisms to upregulate ESRP1 may exert a beneficial therapeutic effect in PDAC.


Asunto(s)
Carcinoma Ductal Pancreático/diagnóstico , Neoplasias Hepáticas/secundario , Neoplasias Pancreáticas/diagnóstico , Proteínas de Unión al ARN/metabolismo , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/genética , Empalme Alternativo , Animales , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/patología , Masculino , Ratones Desnudos , Neoplasias Experimentales , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas de Unión al ARN/genética , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/metabolismo
9.
Plant Biol (Stuttg) ; 16 Suppl 1: 43-9, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24128007

RESUMEN

Gravitational force on Earth is one of the major environmental factors affecting plant growth and development. Spacecraft and the International Space Station (ISS), and a three-dimensional (3-D) clinostat have been available to clarify the effects of gravistimulation on plant growth and development in space and on ground conditions, respectively. Under a stimulus-free environment such as space conditions, plants show a growth and developmental habit designated as 'automorphosis' or 'automorphogenesis'. Recent studies in hormonal physiology, together with space and molecular biology, have demonstrated the close relationships between automorphosis and polar auxin transport. Reduced polar auxin transport in space conditions, or induced by the application of polar auxin transport inhibitors, substantially induced automorphosis or automorphosis-like growth and development, indicating that polar auxin transport is responsible for graviresponse in plants. This concise review covers graviresponse in plants and automorphosis observed in space conditions, and polar auxin transport related to graviresponse in etiolated Alaska and ageotropum pea seedlings. Molecular aspects of polar auxin transport clarified in recent studies are also described.


Asunto(s)
Gravitropismo/fisiología , Ácidos Indolacéticos/metabolismo , Plantas/metabolismo , Transporte Biológico , Medio Ambiente Extraterrestre , Desarrollo de la Planta
10.
Acta odontol. venez ; 52(1)2014. tab, graf
Artículo en Español | LILACS | ID: lil-777812

RESUMEN

El presente estudio evaluó la rugosidad y pigmentación de dos resinas compuestas nanohíbridas, Tetric EvoCeram (TE) y Ceram X Duo (CD) después del uso de dos técnicas de pulido: de paso único Pogo (P) y múltiples pasos Sof-Lex Discs (S). Sesenta especímenes fueron confeccionados con dimensiones de 7mm x 2mm, subdivididos en grupos (n=10): G1- TE+ P;G2- TE+S; G3- TE control; G4- CD + P;G5- CD + P; G6- CD control. Se realizó la toma de color a través de espectrofotómetro VITA Easyshade y lectura de la rugosidad superficial por el rugosímetro Surf-Corder. Los especímenes fueron inmersos en solución de café soluble por siete días, dejando dos especímenes de cada grupo almacenados en agua destilada durante el periodo del experimento. Después de ese tiempo, se realizó una nueva toma de color de los especímenes y los datos fueron analizados estadísticamente a través del test de Anova y Tukey. Para los dos sistemas de pulido hubo diferencia estadísticamente significante en relación a las dos resinas compuestas (p<0,05). El grupo control presentó superficies más lisas que las demás, mientras que en los especímenes pulidos con sistema Sof-Lex presentaron superficies más lisas que las pulidas con Pogo. Los especímenes pulidos con sistema de "múltiples pasos" obtuvieron valores menores de variación de color (?E*), mientras que las muestras tratadas con tira de poliéster fueron las que más se pigmentaron. Cuando se comparan las dos técnicas de pulido, la técnica de múltiples pasos resultó tener una mayor lisura superficial y menor variación de color.


This study compared two different nanohybrid composite resins, Tetric EvoCam and Ceram X Duo about its roughness and staining, after two polishing techniques, "one step" Pogo and "multiple steps" Sof-Lex Disc. Sixty test-samples were fabricated with dimensions of 7mm x 2mm, divided into groups: (n=10): G1- TE+ P;G2- TE+S; G3- TE control; G4- CD + P;G5- CD + P; G6- CD control. A color check was performed with VITA Easyshade spectrophotometer and a reading of the surface roughness by the Surf-Corder (Kosaka Lab. SE 1700). So, the specimens were immersed in a solution of solved coffee (Nescafe) for seven days, with two specimens of each group stored in distilled water during the study period. After this period, it was performed another color check of the specimens and the data was statistically analyzed by ANOVA and Tukey test. For both polishing systems there was statistically significant differences, on both resin composites (p<0.05). The control group showed smoother surfaces than the others, while that the ones polished with Sof-Lex presented smoother surfaces than the ones polished with the Pogo system. The specimens polished with the "multiple steps" system had lower values of color variation (?E*), while that the specimens treated with polyester strips were the most stained ones. When comparing the two polishing techniques, the technique of "multiples steps" resulted in greater smoothness surface and less color variation.


Asunto(s)
Masculino , Femenino , Pulido Dental , Polímeros/uso terapéutico , Resinas Compuestas/análisis , Resinas Compuestas/farmacocinética , Materiales Dentales , Cementos de Resina
11.
Transl Psychiatry ; 1: e24, 2011 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-22832526

RESUMEN

Bipolar disorder (BD) is a severe mental disorder characterized by recurrent episodes of mania and depression. Serotonin transporter (HTT) is a target of antidepressants and is one of the strongest candidate molecules of mood disorder, however, genetic study showed equivocal results. Here, we performed promoter-wide DNA methylation analysis of lymphoblastoid cell lines (LCLs) derived from two pairs of monozygotic twins discordant for BD. To rule out the possible discordance of copy number variation (CNV) between twins, we performed CNV analysis and found the copy number profiles were nearly identical between the twin pairs except for immunoglobulin-related regions. Among the three genes we obtained as candidate regions showing distinct difference of DNA methylation between one of the two pairs, hypermethylation of SLC6A4, encoding HTT, in the bipolar twin was only confirmed by bisulfite sequencing. Then, promoter hypermethylation of SLC6A4 in LCLs of BD patients was confirmed in a case-control analysis. DNA methylation of SLC6A4 was significantly correlated with its mRNA expression level in individuals with the S/S genotype of HTTLPR, and mRNA expression level was lower in BD patients carrying the S/S genotype. Finally, DNA methylation of the same site was also higher in the postmortem brains of BD patients. This is the first study to report the role of epigenetic modification of SLC6A4 in BD using an unbiased approach, which provides an insight for its pathophysiology.


Asunto(s)
Trastorno Bipolar/genética , Metilación de ADN/genética , Enfermedades en Gemelos , Epigenómica/métodos , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética , Adulto , Trastorno Bipolar/metabolismo , Estudios de Casos y Controles , Línea Celular Transformada , Epigenómica/instrumentación , Femenino , Predisposición Genética a la Enfermedad , Humanos , Activación de Linfocitos/genética , Masculino , Persona de Mediana Edad , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo , Gemelos Monocigóticos
12.
Anim Genet ; 39(1): 22-7, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18254733

RESUMEN

The porcine MX1 and MX2 promoters were characterized in this study. Sequencing of the 332-bp MX1 promoter region identified 15 substitutions and insertions at three positions in 21 pigs from 15 breeds, in which nine genotypes were classified. Among the nine genotypes, no statistically significant differences in the promoter activities were observed after interferon (IFN-alpha 2b) treatment of transiently transfected cells containing constructs with luciferase reporter plasmids. The 341-bp MX2 promoter region contained regulatory sequences for ISRE, GC box, Sp1 and AP-1, as well as a TATA box. Nucleotide sequences of the MX2 promoter region revealed four substitutions and one deletion, in which six genotypes were classified. Among the six genotypes, a statistically significant difference (P < 0.05) in MX2 promoter activities after IFN-alpha 2b treatment was detected in transiently transfected cells.


Asunto(s)
Proteínas de Unión al GTP/genética , Polimorfismo Genético , Regiones Promotoras Genéticas , Porcinos/genética , Animales , Secuencia de Bases , ADN/genética , Cartilla de ADN/genética , Variación Genética , Genotipo , Interferón alfa-2 , Interferón-alfa/farmacología , Células LLC-PK1 , Datos de Secuencia Molecular , Mutagénesis Insercional , Proteínas de Resistencia a Mixovirus , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas/efectos de los fármacos , Proteínas Recombinantes , Eliminación de Secuencia , Especificidad de la Especie , Sus scrofa/clasificación , Sus scrofa/genética , Porcinos Enanos/clasificación , Porcinos Enanos/genética , Transfección
13.
Immunogenetics ; 59(1): 59-67, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17119954

RESUMEN

Millennia-long selective pressure of single-strand RNA viruses on the bovine Mx locus has increased the advantages of using the bovine Mx protein to evaluate the ultimate significance of the antiviral role of Mx proteins. The conclusions of research based only on the bovine Mx1 protein showed the need for comprehensive studies that demonstrate the role of all isoforms, individually or together, especially in the presence of a second isoform, the bovine Mx2 gene. This study provides information about bovine and water buffalo Mx2 genes, as well as their allelic polymorphism and basic antiviral potential. Observation of an Mx2 cDNA sequence (2,381 bp) obtained from 15 animals from 11 breeds using primers based on a previous sequence (NCBI accession no. AF335147) revealed several nucleotide substitutions, with eight different alleles and two amino acid exchanges: Gly to Ser at position 302 and Ile to Val at position 354, though the latter was found only in the NCBI database. A water buffalo Mx2 cDNA sequence was identified for the first time, revealing 46 nucleotide substitutions with 12 amino acid variations, in addition to a 9-bp insertion in the 5' untranslated region UTR, compared with the bovine Mx2 cDNA. Transfected 3T3 cells expressing bovine Mx2 mRNAs coding Gly or Ser at position 302, water buffalo Mx2 mRNA, positive control bovine Mx1 mRNA-expressing cells, and negative control parental 3T3 were subjected to infection with recombinant vesicular stomatitis virus (VSVDeltaG*-G), as were empty pCI-neo vector-transfected cells. The positive control and all cells expressing Mx2 mRNAs displayed significantly higher levels of antiviral activity against VSVDeltaG*-G (P < 0.01) than did the negative controls.


Asunto(s)
Búfalos/inmunología , Bovinos/inmunología , Proteínas de Unión al GTP/genética , Proteínas de Unión al GTP/fisiología , Polimorfismo Genético , Virus ARN/inmunología , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Búfalos/genética , Búfalos/virología , Bovinos/genética , Bovinos/virología , Proteínas de Unión al GTP/clasificación , Expresión Génica , Ratones , Datos de Secuencia Molecular , Proteínas de Resistencia a Mixovirus , Células 3T3 NIH , Filogenia , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Transfección , Virus de la Estomatitis Vesicular Indiana/inmunología
15.
Biochem Genet ; 44(9-10): 437-48, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16955367

RESUMEN

A single amino acid substitution between Asn and Ser at position 631 in the chicken Mx protein has been reported to determine resistant and sensitive antiviral activity. In this study, we investigate whether various kinds of chicken breeds and jungle fowls carry the resistant or sensitive Mx allelic gene by using the mismatched PCR-restriction fragment length polymorphism (RFLP) technique. In total, 271 samples from 36 strains of 17 chicken breeds and from 3 kinds of jungle fowls were examined. The rates of the resistant Mx gene and sensitive gene were 59.2% and 40.8%, respectively. Only a Red jungle fowl captured in Laos carried the resistant Mx gene, and the other three Red jungle fowls from Indonesia and Gray and Green jungle fowls all had the sensitive Mx gene. These results were confirmed by the determination of amino acid sequences in the GTPase effector domain of jungle fowls.


Asunto(s)
Polimorfismo Genético , Proteínas/genética , Alelos , Sustitución de Aminoácidos , Animales , Antivirales , Secuencia de Bases , Pollos , ADN , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Proteínas/química
16.
Br J Ophthalmol ; 89(4): 504-7, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15774933

RESUMEN

AIMS: This study sought to elucidate the effects of timolol and dorzolamide on intraocular pressure (IOP) and retinal ganglion cell (RGC) death in an experimental model of glaucoma in rat. METHODS: Mild elevation of IOP was induced in rats by intracameral injection of India ink and subsequent laser trabecular photocoagulation. IOP was measured before the surgical procedures and weekly thereafter. Timolol (0.5%), timolol XE (0.5%), dorzolamide (1%), and artificial tears (vehicle) were topically applied daily. Retinal sections were prepared for histology to determine RGC number. RESULTS: Timolol, timolol XE, and dorzolamide induced a significant reduction in IOP (p<0.05) and counteracted the reduction in RGC number that occurred in vehicle treated glaucomatous eyes (p<0.05). The coefficient of correlation between RGC number and IOP was significant in the dorzolamide treated group (r = -0.908, p<0.005), but not in other groups (p>0.05). CONCLUSIONS: Both timolol formulation and dorzolamide reduced IOP and protected RGCs in a rat model of experimental glaucoma. It cannot be ruled out that timolol might protect RGCs by additional mechanisms other than simply lowering of IOP.


Asunto(s)
Antihipertensivos/uso terapéutico , Glaucoma/tratamiento farmacológico , Células Ganglionares de la Retina/efectos de los fármacos , Sulfonamidas/uso terapéutico , Tiofenos/uso terapéutico , Timolol/uso terapéutico , Animales , Recuento de Células , Supervivencia Celular/efectos de los fármacos , Citoprotección , Modelos Animales de Enfermedad , Glaucoma/patología , Glaucoma/fisiopatología , Presión Intraocular/efectos de los fármacos , Masculino , Soluciones Oftálmicas , Ratas , Ratas Wistar , Células Ganglionares de la Retina/patología
17.
Anim Genet ; 35(3): 182-7, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15147388

RESUMEN

Bovine MX1 cDNAs consisting of 2280 bp from 11 animals of five breeds and from a cultured cell line were sequenced and compared with previously reported data. Ten nucleotide substitutions were synonymous mutations, and a single nucleotide substitution at 458 resulted in an amino acid exchange of Ile (ATT) and Met (ATG). A 13-bp deletion-insertion mutation was also found in the 3'-UTR. Based on the nucleotide substitutions found in this study, bovine MX1 cDNA was classified into 11 genotypes. A phylogenetic tree of the 11 genotypes suggested that the genotypes observed in Brahman were a great genetic distance from other genotypes. An 18-bp deletion-insertion variation at position 171 was found to be the result of alternative splicing. The 18-bp deletion-insertion is located at the boundary between exon 3 and intron 3. Permanently transfected 3T3 cell lines expressing bovine MX1 mRNA were established to analyse the antiviral potential against VSVDeltaG*-G infection. Transfected cell clones expressing bovine MX1 mRNA showed a significantly smaller number of cells infected with VSVDeltaG*-G compared with the control cells. These results indicate that the bovine MX1 protein has potent antiviral activity.


Asunto(s)
Antivirales/genética , Bovinos/genética , Proteínas de Unión al GTP/genética , Filogenia , Polimorfismo Genético , Virus de la Estomatitis Vesicular Indiana/genética , Células 3T3 , Empalme Alternativo , Animales , Secuencia de Bases , Análisis por Conglomerados , Cartilla de ADN , ADN Complementario/genética , Proteínas de Unión al GTP/clasificación , Ratones , Datos de Secuencia Molecular , Mutación Missense/genética , Proteínas de Resistencia a Mixovirus , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Transfección
18.
Arch Virol ; 148(9): 1713-20, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14505084

RESUMEN

Arapid and simple procedure is described to detect the genomic RNA molecule of Japanese yam mosaic potyvirus (JYMV). This method, named RT-LAMP, allows direct detection of RNA from infected plants without careful RNA extraction, rapid thermal cycling and gel electrophoresis. RT-LAMP was successfully applied to leaves, propagules and roots of Japanese yam infected with JYMV. One of the characteristics of the RT-LAMP method is its ability to synthesize an extremely large amount of DNA. Accordingly, a large amount of by-product, pyrophospate ion, is produced yielding a white precipitate of magnesium pyrophosphate in the reaction mixture. The presence or absence of this white precipitate allows easy detection of the amplification of JYMV genomic RNA without gel electrophoresis.


Asunto(s)
Dioscorea/virología , Técnicas de Amplificación de Ácido Nucleico/métodos , Potyvirus/aislamiento & purificación , Secuencia de Bases , Datos de Secuencia Molecular , Potyvirus/genética
19.
Chem Pharm Bull (Tokyo) ; 49(11): 1495-7, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11724248

RESUMEN

In a study on the metabolism of flavonoids, the isoflavone genistein was administered orally to rats. Urine samples were collected and treated with beta-glucuronidase and arylsulfatase. Genistein and its metabolites, 4',5,7-trihydroxyisoflavanone (M1), 4',7-dihydroxyisoflavan (M2), and p-ethylphenol (M3) were isolated from the urine following treatment with enzymes. The structures of M1, M2, and M3 were determined on the basis of chemical and spectral data.


Asunto(s)
Genisteína/administración & dosificación , Genisteína/orina , Administración Oral , Animales , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/orina , Genisteína/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley
20.
Adv Space Res ; 27(5): 1017-22, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11596632

RESUMEN

Effects of simulated microgravity and hypergravity on the senescence of oat leaf segments excised from the primary leaves of 8-d-old green seedlings were studied using a 3-dimensional (D) clinostat as a simulator of weightlessness and a centrifuge, respectively. During the incubation with water under 1-g conditions at 25 degrees C in the dark, the loss of chlorophyll of the segments was found dramatically immediately after leaf excision, and leaf color completely turned to yellow after 3-d to 4-d incubation. In this case kinetin (10 micromolar) was effective in retarding senescence. The application of simulated microgravity conditions on a 3-D clinostat enhanced chlorophyll loss in the presence or absence of kinetin. The loss of chlorophyll was also enhanced by hypergravity conditions (ca. 8 to 16 g), but the effect was smaller than that of simulated microgravity conditions on the clinostat. Jasmonates (JAs) and abscisic acid (ABA) promoted senescence under simulated microgravity conditions on the clinostat as well as under 1-g conditions. After 2-d incubation with water or 5-d incubation with kinetin, the endogenous levels of JAs and ABA of the segments kept under simulated microgravity conditions on the clinostat remained higher than those kept under 1-g conditions. These findings suggest that physiological processes of leaf senescence and the dynamics of endogenous plant hormone levels are substantially affected by gravity.


Asunto(s)
Adenina/análogos & derivados , Avena/crecimiento & desarrollo , Reguladores del Crecimiento de las Plantas/metabolismo , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Simulación de Ingravidez , Ácido Abscísico/metabolismo , Acetatos/metabolismo , Adenina/farmacología , Avena/metabolismo , Centrifugación , Clorofila/metabolismo , Ciclopentanos/metabolismo , Oscuridad , Gravitación , Hipergravedad , Cinetina , Oxilipinas , Reguladores del Crecimiento de las Plantas/farmacología , Hojas de la Planta/efectos de los fármacos , Rotación
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