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1.
Rheumatol Int ; 36(2): 249-54, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26350270

RESUMEN

Rheumatoid arthritis (RA) is a multifactorial disease. A combination of genetic and environmental risk factors contributes to its etiology. Several genes have been reported to be associated with susceptibility to the development of RA. The MHC2TA and FCRL3 genes have been associated previously with RA in Swedish and Japanese populations, respectively. In two recent reports, we show an association between FCRL3 and juvenile rheumatoid arthritis (JRA), and MHC2TA and acute coronary syndrome (ACS) in Mexican population. We assessed the association between three single nucleotide polymorphisms (SNPs) of the MHC2TA (-168G/A; rs3087456, and +16G/C; rs4774) and FCRL3 (-169T/C; rs7528684) genes and rheumatoid arthritis in Mexican population through a genotyping method using allelic discrimination assays with TaqMan probes. Our case-control study included 249 patients with RA and 314 controls. We found no evidence of an association between the MHC2TA -168G/A and +1614G/C or FCRL3 -169T/C polymorphisms and RA in this Mexican population. In this cohort of Mexican patients with RA, we observed no association between the MHC2TA or FCRL3 genes and this autoimmune disease.


Asunto(s)
Artritis Reumatoide/genética , Proteínas Nucleares/genética , Polimorfismo de Nucleótido Simple , Receptores Inmunológicos/genética , Transactivadores/genética , Adulto , Artritis Reumatoide/diagnóstico , Artritis Reumatoide/epidemiología , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Haplotipos , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Fenotipo , Factores de Riesgo
3.
Reprod Domest Anim ; 48(2): 345-52, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22957657

RESUMEN

In a farm of grandparent broiler breeder chickens, we followed the development of 350 roosters from 6 to 55 weeks of age. Data collected and evaluated from these males included body weight, testicular weight, histologic and immunohistochemistry studies of the testes, hormone levels (testosterone, estradiol and corticosterone) and sperm production. The objective was to understand the factors that affect or influence hatch loss that is commonly observed after 45 weeks of age in breeder flocksare often correlated to broiler breeder male chickens. The results of this study showed that in conjunction with the weight of the rooster, the testicle weight increases quickly after the rooster receives light stimulation. At an older age, the study showed that there is a process of testicular shrinkage, and the same effect is seen in sperm production and testosterone levels in broiler breeder roosters. From the histology evaluation, we defined 5 histologic phases that illustrate the evolution of the testicular tissue: perinatal, infantile, puberty, adult and senile. We observed that the adult males with a body weight <3800 g were infertile or had subfertile levels and also had low levels of testosterone and high levels of corticosterone. In contrast, the heaviest males showed correct testicular vitality, high levels of testosterone and low levels of corticosterone. However, the roosters that had acquired this high body weight were also at risk of having less complete copulations because of their physical mass. The loss of uniformity of the males and the appearance of hierarchies within the flock accompany a decline in the percentages of hatches as a consequence of the poor confirmation of the males for copulation or the restriction to the access to the females. Results of this study show that the decrease in fertility from 45 weeks of age has been associated with a decline in testicular weight, sperm production and the testosterone levels in animals with a sub-par weight. Likewise, decreasing hatch in older flocks may also result from a loss of conformation, and the lack of complete copulations is possible because of animals that are grossly overweight.


Asunto(s)
Peso Corporal/fisiología , Pollos/crecimiento & desarrollo , Pollos/fisiología , Maduración Sexual/fisiología , Espermatogénesis/fisiología , Testículo/anatomía & histología , Envejecimiento/fisiología , Animales , Aromatasa/genética , Aromatasa/metabolismo , Caspasas/genética , Caspasas/metabolismo , Estradiol/genética , Estradiol/metabolismo , Regulación del Desarrollo de la Expresión Génica/fisiología , Inmunohistoquímica , Inhibinas/genética , Inhibinas/metabolismo , Masculino , Tamaño de los Órganos , Testosterona/genética , Testosterona/metabolismo
4.
Chemosphere ; 275: 130030, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33662730

RESUMEN

In this work the ability of Zn2-xCuxCr-CO3 layered double hydroxides (LDHs) as highly efficient DeNOx photocatalysts was studied. LDHs with x = 0, 0.2 and 0.4 were prepared using a coprecipitation method. The samples were characterized by different techniques such as XRD, XPS, FT-IR, ICP-MS, TG, SBET, SEM and Diffuse reflectance (DR). The increased amount of copper ions in the LDH layers gave rise to slight changes in the structure and morphology and an important variation of the optical properties of the LDHs. The prepared ZnCuCr-CO3 photocatalysts exhibited favourable conversion efficiency (51%) and an extraordinary selectivity (97%) for the photochemical NO abatement. The photochemical mechanism was elucidated from DOS, EPR, Femtosecond transient absorption and in-situ DRIFTS studies. The results suggested that the presence of Cu2+ ions in the LDH framework introduced new states in the valence band states, thus favouring the production and mobility of e-/h+ charge carriers and a greater production of ⋅O2- and ⋅OH.


Asunto(s)
Cobre , Hidróxidos , Espectroscopía Infrarroja por Transformada de Fourier , Zinc
5.
RSC Adv ; 10(23): 13405-13409, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35493002

RESUMEN

The compression force with indentation on a polymer brush with chains of unequal lengths is predicted with numerical simulations, as a function of increasing hardness of the grafting surface, finding that properties of the brush are distinguished from those of the surface and that its hardness propagates through the brush.

6.
Genet Mol Res ; 7(1): 7-15, 2008 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-18273814

RESUMEN

The human orosomucoid 1 gene (ORM1) codes an alpha-1-acid glycoprotein that has been classified as an acute-phase reactive protein, and a major drug-binding serum component, as well as an immunomodulatory protein with genetic polymorphisms. Evaluation of ORM variation through isoelectric focusing and immunobloting has revealed a world-wide distribution of the ORM1 F and ORM1 S alleles. We evaluated and examined the genetic characteristics of two Mexican populations that have different anthropological and cultural antecedents, examining two ORM1 genotypes (exon 1 - A/G (Gln20Arg) and exon 5 G/A (Val156Met)) in 145 individuals, using nested polymerase chain reaction, sequencing, and restricted fragment length polymorphism. Mexican Mestizos had higher frequencies of the exon 1 A allele (P = 0.020) and AA genotype (P = 0.018) and lower frequency of the G allele (P = 0.020) when compared to Teenek Amerindians. When we examined exon 5 G/A (Val156Met) polymorphisms, we found significantly higher frequencies of the G allele (P = 0.0007) and the GG genotype (P = 0.0003) in the Mexican Mestizo population. The Teenek population had a significantly higher frequency of the A allele than has been reported for Chinese and African (P < 0.05) populations, and the G/A genotype was more frequently found in this Mexican population than in Chinese, African and European populations (P < 0.05).


Asunto(s)
Exones/genética , Genética de Población , Indígenas Norteamericanos/genética , Orosomucoide/genética , Polimorfismo Genético , Alelos , ADN/genética , ADN/aislamiento & purificación , Frecuencia de los Genes , Variación Genética , Humanos , México , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Análisis de Secuencia de ADN , Estadística como Asunto
7.
J Mol Model ; 23(11): 306, 2017 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-28986687

RESUMEN

The interfacial tension between immiscible liquids is studied as a function of a model linear surfactant length and concentration using coarse-grained, dissipative particle dynamics numerical simulations. The adsorption isotherms obtained from the simulations are found to be in agreement with Langmuir's model. The reduction of the interfacial tension with increasing surfactant concentration is found to display some common characteristics for all the values of chain length modeled, with our predictions being in agreement with Szyszkowski's equation. Lastly, the critical micelle concentration is predicted for all surfactant lengths, finding exponentially decaying behavior, in agreement with Kleven's model. It is argued that these findings can be helpful guiding tools in the interpretation of available experiments and in the design of new ones with new surfactants and polymers.

8.
Rev Port Cardiol ; 20 Suppl 5: V-37-42; discussion V-43-5, 2001 May.
Artículo en Portugués | MEDLINE | ID: mdl-11515299

RESUMEN

The A.A. present a case of Ebstein's Disease, on a woman 48 years old. After stressing the clinical and laboratorial aspects, as well as hemodynamics and angiocardiography data, they summarize the operation, on which was used a human "dura-mater" valve in tricuspid position. There is no knowledge on literature of previous applications of this kind of valve on Ebstein's Disease. The patient, one year after the operation, is improving quiet well.


Asunto(s)
Bioprótesis , Duramadre/trasplante , Anomalía de Ebstein/cirugía , Prótesis Valvulares Cardíacas , Femenino , Humanos , Persona de Mediana Edad
9.
Horm Res ; 34(2): 71-4, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-1982947

RESUMEN

To date, the effects of long-term growth hormone (GH)-releasing hormone [GHRH(1-29)-NH2] treatment on the plasma concentrations of somatostatin-like immunoreactivity (SLI) remain undefined. In the present study, the effect of GHRH(1-29)-NH2 therapy on plasma SLI levels has been studied in 11 non-GH-deficient children. The pattern of administration was 5 micrograms/kg body weight, given subcutaneously once every day. There was no significant change in plasma SLI levels after bolus injection of GHRH(1-29)-NH2 before and during GHRH(1-29)-NH2 therapy. However, plasma SLI rose in basal plasma and nocturnal sleep after 3 months of GHRH(1-29)-NH2 therapy and remained the same during 6 months of treatment with GHRH(1-29)-NH2. The reason for this finding is uncertain, but an increase in SLI release from the enteroinsular axis is a possible explanation. The association of our findings with the role of the circulating SLI on nutrient homeostasis and the effects of GNRH on growth velocity is discussed.


Asunto(s)
Trastornos del Crecimiento/tratamiento farmacológico , Hormona Liberadora de Hormona del Crecimiento/farmacología , Somatostatina/sangre , Estatura/efectos de los fármacos , Niño , Humanos , Inyecciones Subcutáneas , Radioinmunoensayo , Somatostatina/inmunología , Factores de Tiempo
10.
Horm Res ; 30(6): 252-7, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-2907992

RESUMEN

In the present study we report the effects of therapy with growth hormone-releasing factor (1-29)NH2 (GRF) on growth rate, plasma levels of insulin growth factor I (IGF-I) and growth hormone (GH) secretion in 11 children who were selected solely on the basis of their short stature and normal GH secretion on standard provocative tests. All children received GRF for 6 months (5 micrograms/kg body weight subcutaneously) each evening. The 24-hour GH secretory profile was studied before and after 6 months of treatment. Simultaneously, GH secretory responses to single intravenous bolus GRF (1.5 micrograms/kg body weight) were also studied before, during, and 6 months off therapy with GRF(1-29)NH2. Plasma levels of IGF-I were measured before, during (1, 2 and 6 months), and after 6 months off therapy with GRF. Statural growth was measured at 3-month intervals. The peak plasma GH level in response to GRF was 56.04 +/- (SD) 24.46 ng/ml before treatment, and similar results were found after therapy. The 24-hour GH secretory profile did not show differences before, during, and after treatment. Comparably, no differences were found in GH pulse frequency, pulse amplitude, pulse height, pulse increment, pulse area and total area before, and 6 months off therapy with GRF. The increments in serum IGF-I achieved were not significantly different at all intervals studied. All patients increased growth velocities (mean +/- SD, cm/year) in response to GRF therapy. Our results demonstrate that GRF administration was effective in accelerating growth velocity in 11 children without GH deficiency.


Asunto(s)
Trastornos del Crecimiento/tratamiento farmacológico , Hormona Liberadora de Hormona del Crecimiento/análogos & derivados , Fragmentos de Péptidos/uso terapéutico , Estatura/efectos de los fármacos , Niño , Femenino , Hormona del Crecimiento/sangre , Hormona del Crecimiento/metabolismo , Hormona Liberadora de Hormona del Crecimiento/administración & dosificación , Hormona Liberadora de Hormona del Crecimiento/uso terapéutico , Humanos , Inyecciones Subcutáneas , Factor I del Crecimiento Similar a la Insulina/sangre , Masculino , Fragmentos de Péptidos/administración & dosificación , Sermorelina
11.
Acta Anat (Basel) ; 102(3): 308-18, 1978.
Artículo en Inglés | MEDLINE | ID: mdl-685656

RESUMEN

The changes of the rate of RNA synthesis produced by castration and estradiol injection on the surface endometrial cells of the rat are profited to study the variations in the number and size of nuclear ribonucleoprotein structures and in the disposition of chromatin. Two-dimensional measurements on sections contrasted with preferential procedures were employed to estimate the fraction of nuclear volume occupied by each element. Young adult rats in estrus are used as controls. 3 weeks after ovariectomy, the area fraction occupied by the nucleolus is reduced almost to a third of the control value, while the number of perichromatin granules per unit area of nucleus has significantly increased. A single injection of 20 microgram of estradiol produces a rapid decrease of the number of perichromatin granules to a fourth of the value of castrate animals, in 15-30 min, followed by a slow increase. Nucleolar area fraction begins to increase 2 h after estrogen administration and at 24 h it is higher than in controls. It is concluded that the changes of the nucleolar volume are due to the effects of estradiol on the synthesis of nucleolar RNA, while the variations of perichromatin granules are produced by the combination of the effect on extranucleolar RNA synthesis and on its processing and/or transporting to the cytoplasm. Both effects are independent and undergo different temporal courses.


Asunto(s)
Castración , Núcleo Celular/ultraestructura , Endometrio/ultraestructura , Estradiol/farmacología , Animales , Núcleo Celular/efectos de los fármacos , Endometrio/citología , Endometrio/efectos de los fármacos , Células Epiteliales , Epitelio/ultraestructura , Femenino , Microscopía Electrónica , ARN/biosíntesis , Ratas
12.
Arch Inst Cardiol Mex ; 51(3): 273-7, 1981.
Artículo en Español | MEDLINE | ID: mdl-7283539

RESUMEN

Ten patients with mitral stenosis underwent right and left heart catheterization. In order to assess the diastolic properties of these ventricles an hemodynamic-echocardiografic techniques was employed. Left ventricular pressure and an echocardiogram of the body of the left ventricle were simultaneously registered. Ventricular volume was determined using the minor axis (T) of the left ventricle measured form the echogram and assuming the long axis (L) from the L to T relationship observed in the left cineventriculography. Using a microcromputer, a smoothed volume-time curve was obtained, together with its first derivative and a pressure-volume loop. The exponential portion of the diastolic loop was used to obtain a felt ventricular stiffness index at zero volume. End diastolic volume and ejection fraction were normals. Left ventricular filling was impaired but ventricular stiffness was found in the normal range. It is concluded that the proposed method permits the simultaneous obtention of pressure volume data. The processing of complex data can be achieved with a pocket microcomputer. There is no evidence of a left ventricular compliance defect in mitral stenosis.


Asunto(s)
Ecocardiografía , Ventrículos Cardíacos/fisiopatología , Estenosis de la Válvula Mitral/diagnóstico , Adulto , Cateterismo Cardíaco , Diástole , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Hemodinámica , Humanos , Masculino , Microcomputadores , Persona de Mediana Edad , Estenosis de la Válvula Mitral/fisiopatología , Radiografía
13.
Artif Organs ; 12(1): 81-2, 1988 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3355388

RESUMEN

Early obstruction of the venous tubing is a frequent complication after peritoneovenous (PV) shunting for ascites in cirrhosis and results in a high incidence of shunt failure. A titanium catheter tip, developed because of this material's thromboresistance, was employed in 13 consecutive cirrhotic patients receiving a LeVeen shunt for intractable ascites. While the mean interval before shunt occlusion was 4 +/- 3 months in our previous studies, none of the patients in the present series had venous catheter occlusion during follow-up, which averaged 8 +/- 2 months. The use of titanium in the venous tubing of PV shunts may significantly prolong the patency and function of these devices.


Asunto(s)
Cateterismo , Derivación Peritoneovenosa/instrumentación , Titanio , Diseño de Equipo , Estudios de Evaluación como Asunto , Fibrosis/terapia , Humanos
14.
Genet. mol. res. (Online) ; Genet. mol. res. (Online);7(1): 7-15, Jan. 2008. tab, ilus
Artículo en Inglés | LILACS | ID: lil-553765

RESUMEN

The human orosomucoid 1 gene (ORM1) codes an alpha-1-acid glycoprotein that has been classified as an acute-phase reactive protein, and a major drug-binding serum component, as well as an immunomodulatory protein with genetic polymorphisms. Evaluation of ORM variation through isoelectric focusing and immunobloting has revealed a world-wide distribution of the ORM1 F and ORM1 S alleles. We evaluated and examined the genetic characteristicsof two Mexican populations that have different anthropological and cultural antecedents, examining two ORM1 genotypes (exon 1 - A/G (Gln20Arg) and exon 5 G/A (Val156Met)) in 145 individuals, using nested polymerase chain reaction, sequencing, and restrited fragment length polymorphism. Mexican Mestizos had higher frequencies of the exon 1 A allele (P = 0.020) and AA genotype(P = 0.018) and lower frequency of the G allele (P = 0.020) when compared to Teenek Amerindians. When we examined exon 5 G/A (Val156Met) polymorphisms, we found significantly higher frequencies of the G allele (P = 0.0007) and the GG genotype (P = 0.0003) in the Mexican Mestizo population. The Teenek population had a significantly higher frequency of the A allele than has been reported for Chinese and African (P < 0.05) populations, and the G/A genotype was more frequently found in this Mexican population than in Chinese, African and European populations (P < 0.05).


Asunto(s)
Humanos , Exones/genética , Genética de Población , Indígenas Norteamericanos/genética , Orosomucoide/genética , Polimorfismo Genético , Alelos , ADN , Frecuencia de los Genes , Variación Genética , México , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Análisis de Secuencia de ADN , Estadística como Asunto
18.
Arch. Inst. Cardiol. Méx ; 51(3): 273-7, 1981.
Artículo en Español | LILACS | ID: lil-5538

RESUMEN

Diez pacientes con estenosis mitral fueron estudiados mediante cateterismo cardiaco derecho e izquierdo. A fin de determinar las propiedades diastolicas del ventriculo izquierdo se utilizo una tecnica hemodinamica-ecocardiografica, con la que se registraron simultaneamente la presion intraventricular y un ecocardiograma a nivel del cuerpo del ventriculo izquierdo. El volumen ventricular fue medido determinando el diametro menor directamente del eco ventricular y asumiendo el diametro mayor (L) de la relacion L/T obtenida de la cineventriculografia izquierda. Con una microcomputadora se obtuvo una curva suavizada de volumen-tiempo, su derivada y un asa de presion-volumen. La porcion diastolica exponencial del asa fue utilizada para obtener un indice de rigidez ventricular a volumen cero. El volumen diastolico y la fraccion de expulsion fueron normales. El llenado ventricular se encontro disminuido y la rigidez ventricular normal. Se concluye que el metodo propuesto permite facilmente la obtencion de datos simultaneos de presion-volumen, que el procesamiento de datos complejos puede hacerse con una microcomputadora de bolsillo y que no hay un defecto de las propiedades elasticas del ventriculo


Asunto(s)
Presión Arterial , Ecocardiografía , Estenosis de la Válvula Mitral
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