Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Más filtros










Intervalo de año de publicación
1.
Morphologie ; 108(361): 100760, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38157748

RESUMEN

BACKGROUND: Myocardial bridge (MB) is described as an abnormal band of myocardium covering a variable portion of any coronary artery. METHODS: The current study explores the presence of MB throughout the coronary arterial system and provides a morphometric description through instrumented dissection of a sample of 100 human hearts. The study shows a higher prevalence of MB in the Mexican population than in previous reports. RESULTS: In the total sample (n=100), MB was identified in 96% of it. A total of 421 MBs were observed, with a mean of 4.38mm (±0.28) per dissected heart. The most frequently affected vessel is the anterior interventricular artery where a total of 52 MBs were found, of the total sample studied. DISCUSSION: The high prevalence of MB among Mexican patients could be the result of a genetic association for this population or the neoformation of MB after birth due to lifestyle-associated factors. Further studies are required to better understand the high prevalence of MB among Mexican subjects.


Asunto(s)
Puente Miocárdico , Humanos , México/epidemiología , Masculino , Femenino , Prevalencia , Puente Miocárdico/epidemiología , Puente Miocárdico/patología , Persona de Mediana Edad , Adulto , Anciano , Vasos Coronarios/anatomía & histología , Anciano de 80 o más Años , Miocardio/patología , Adulto Joven
2.
Rev Sci Instrum ; 89(7): 073303, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30068099

RESUMEN

In this work, two compact, permanent magnet, electron spectrometers have been built to measure the electron beam energy at the Dual Axis Radiographic Hydrodynamic Test facility. Using H- and OH- anions, the spectrometers were calibrated at the Special Technologies Laboratory in Santa Barbara, California (USA). The spectrometers were mounted on a custom drift tube that allows the magnet assemblies to be translated, which increases the path length of the electrons traveling through the magnetic field and therefore increases the upper bound of the measurable electron kinetic energy. The measurable range of electron kinetic energies is between 2.8 MeV-4.1 MeV for the first spectrometer and 14.1 MeV-21.1 MeV for the second spectrometer, with an overall measurement uncertainty of 0.32%.

3.
Chemosphere ; 86(10): 985-93, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22197016

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic substances which are resistant to environmental degradation due to their highly hydrophobic nature. Soils contaminated with PAHs pose potential risks to human and ecological health, therefore concern over their adverse effects have resulted in extensive studies on their removal from contaminated soils. The main purpose of this study was to compare experimental results of PAHs removal, from a natural certified soil polluted with PAHs, by biological methods (using bioaugmentation and biostimulation in a solid-state culture) with those from supercritical fluid extraction (SFE), using supercritical ethane as solvent. The comparison of results between the two methods showed that maximal removal of naphthalene, acenaphthene, fluorene, and chrysene was performed using bioremediation; however, for the rest of the PAHs considered (fluoranthene, pyrene, and benz(a)anthracene) SFE resulted more efficient. Although bioremediation achieved higher removal ratios for certain hydrocarbons and takes advantage of the increased rate of natural biological processes, it takes longer time (i.e. 36 d vs. half an hour) than SFE and it is best for 2-3 PAHs rings.


Asunto(s)
Cromatografía con Fluido Supercrítico , Restauración y Remediación Ambiental/métodos , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes del Suelo/análisis , Biodegradación Ambiental , Hidrocarburos Policíclicos Aromáticos/química , Hidrocarburos Policíclicos Aromáticos/metabolismo , Suelo , Contaminantes del Suelo/química , Contaminantes del Suelo/metabolismo
4.
Parasitol Res ; 101(6): 1627-35, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17726617

RESUMEN

To investigate the importance of serine proteases in Leishmania amazonensis promastigotes, we analyzed the effects of classical serine protease inhibitors and a Kunitz-type inhibitor, obtained from sea anemone Stichodactyla helianthus (ShPI-I), on the viability and morphology of parasites in culture. Classical inhibitors were selected on the basis of their ability to inhibit L. amazonensis serine proteases, previously described. The N-tosyl-L: -phenylalanine chloromethyl ketone (TPCK) and benzamidine (Bza) inhibitors, which are potential Leishmania proteases inhibitors, in all experimental conditions reduced the parasite viability, with regard to time dependence. On the other hand, N-tosyl-lysine chloromethyl ketone (TLCK) did not significantly affect the parasite viability, as it was poor Leishmania enzymes inhibitor. Ultrastructural analysis demonstrated that both Bza and TPCK induced changes in the flagellar pocket region with membrane alteration, including bleb formation. However, TPCK effects were more pronounced than those of Bza in Leishmania flagellar pocket in plasma membrane, and intracellular vesicular bodies was visualized. ShPI-I proved to be a powerful inhibitor of L. amazonensis serine proteases and the parasite viability. The ultrastructural alterations caused by ShPI-I were more dramatic than those induced by the classical inhibitors. Vesiculation of the flagellar pocket membrane, the appearance of a cytoplasmic vesicle that resembles an autophagic vacuole, and alterations of promastigotes shape resulted.


Asunto(s)
Leishmania mexicana/efectos de los fármacos , Leishmania mexicana/crecimiento & desarrollo , Serina Endopeptidasas/metabolismo , Inhibidores de Serina Proteinasa/farmacología , Animales , Colorimetría , Leishmania mexicana/enzimología , Leishmania mexicana/ultraestructura , Microscopía Electrónica , Pruebas de Sensibilidad Parasitaria , Sales de Tetrazolio , Tiazoles
5.
Toxicon ; 43(2): 219-23, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15019482

RESUMEN

An inhibitor active against pancreatic trypsin was found in the crude extract from the sea hares Aplysia dactylomelaRang, 1828. A stronger inhibitory activity against human plasma kallikrein was detectable after treating this extract at 60 degrees C, for 30 min. The plasma kallikrein inhibitor (AdKI) purification was achieved by acetone fractionation (80%) v/v, ion-exchange chromatography on Mono Q column and gel filtration chromatography on Superdex 75 column (FPLC system). By the latter a molecular mass of 2900 Da was estimated. The purified inhibitor strongly inhibits human plasma kallikrein with a K(i) value of 2.2 x 10(-10)M, while human plasmin and pancreatic trypsin were inhibited with K(i) values of 1.8 x 10(-9) and 4.7 x 10(-9)M, respectively. Chymotrypsin, pancreatic elastase, pancreatic kallikrein and thrombin are not inhibited. The effect of AdKI on plasma kallikrein was confirmed by the prolongation of activated partial thromboplastin time, using a clotting time assay. The inhibitor did not affect prothrombin time or thrombin time. AdKi is a more specific inhibitor than other serine proteinase inhibitors from marine invertebrates.


Asunto(s)
Aplysia/química , Calicreína Plasmática/antagonistas & inhibidores , Animales , Coagulación Sanguínea/efectos de los fármacos , Fraccionamiento Químico , Cromatografía en Gel , Humanos , Factores de Tiempo
6.
Cienc. ginecol ; 6(1): 1-6, ene. 2002. tab
Artículo en Es | IBECS | ID: ibc-14242

RESUMEN

La endometriosis se define como la presencia de tejido endometrial ectópico fuera de la cavidad uterina normal. El tratamiento médico convencional tiene como objetivo eliminar o disminuir los depósitos de tejido endometrial ectópico. Hoy en día todavía no está clara la mejor estrategia terapéutica para esta patología. La elección del tratamiento está condicionada por múltiples factores (edad, fertilidad, gravedad del proceso,...) En este artículo se revisan las diferentes posibilidades de tratamiento médico de la endometriosis (AU)


Asunto(s)
Femenino , Humanos , Endometriosis/tratamiento farmacológico
7.
Rev. iberoam. trombos. hemost. (Ed. impr.) ; 13(3): 110-112, sept. 2000. graf
Artículo en ES | IBECS | ID: ibc-11762

RESUMEN

Hay evidencia de la presencia de alteraciones en la coagulación que pueden agravar el estado de preeclampsia. Por una parte se ha involucrado a las células mononucleares y por tanto a la generación de factor tisular y por otra a la resistencia a la proteína C como mecanismos en la etiopatogenia de problemas trombóticos. El objetivo del presente trabajo fue evaluar estos factores en una muestra de 20 mujeres embarazadas con preeclampsia y 20 mujeres embarazadas sanas. Estadísticamente no se encontraron diferencias con relacion a uno y otro grupo, con la salvedad de 2 mujeres del grupo con preeclampsia que mostraron resistencia a la proteína C. (AU)


Asunto(s)
Adulto , Embarazo , Femenino , Humanos , Preeclampsia/sangre , Leucocitos Mononucleares/metabolismo , Proteína C/farmacología , Coagulación Sanguínea/fisiología , Factor VIII/biosíntesis , Estudios de Casos y Controles , Pruebas de Coagulación Sanguínea
8.
Prep Biochem Biotechnol ; 29(1): 23-33, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10069430

RESUMEN

In this work, we report the isolation of a factor from the culture supernatant of confluent fibroblasts from human cervix with the diagnosis of uterine myomatosis. This factor possesses the capacity to inhibit the proliferation of normal fibroblasts. The proliferation inhibitor factor (PIF) was purified from the culture supernatant by precipitation with 80% ammonium sulfate, and by molecular sieve chromatography. Our results indicate that PIF is a protein of 23 kDa, which is highly sensitive to trypsin treatment, and is thermolabile, since temperatures equal to, or above, 60 degrees C eliminate the protein activity in 15 to 20 min. Western blot analyses identified no cross reactions of the purified PIF with TGF-alpha, TNFalpha, IFNgamma, or IL-1beta, suggesting that PIF is a new protein belonging to the group of factors secreted by fibroblasts able to inhibit cellular proliferation.


Asunto(s)
Inhibidores de Crecimiento/aislamiento & purificación , Leiomioma/química , Proteínas de Neoplasias/aislamiento & purificación , Neoplasias Uterinas/química , Western Blotting , Recuento de Células , Cromatografía en Gel , Relación Dosis-Respuesta a Droga , Factor de Crecimiento Epidérmico/farmacología , Femenino , Fibroblastos/química , Violeta de Genciana/análisis , Humanos , Interferón gamma/farmacología , Interleucina-1/farmacología , Factor de Crecimiento Transformador beta/farmacología , Células Tumorales Cultivadas , Factor de Necrosis Tumoral alfa/farmacología
9.
Vet Pathol ; 35(6): 547-9, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9823599

RESUMEN

A review of case materials at the Armed Forces Institute of Pathology identified six cases of prostatitis in domestic ferrets (Mustela putorius furo). Five of these ferrets (83%) had one or more cysts and the remaining ferret had a paraprostatic cyst. Three of the six ferrets (50%) exhibited various degrees of prostatic squamous metaplasia. Inflammation ranged from subacute to chronic-active or pyogranulomatous. In addition to the prostatic lesions, hyperplastic and/or neoplastic adrenocortical lesions were present in 4/6 (66%) ferrets; 1/6 (17%) ferrets had previously been clinically diagnosed with adrenal gland-associated endocrinopathy. The remaining ferret had previously had the right adrenal gland removed, but the reason for the removal is unknown. Based upon the histologic findings in these six ferrets, there appears to be an association between proliferative adrenal lesions and cystic prostatitis in domestic ferrets.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/veterinaria , Quistes/veterinaria , Hurones , Próstata/patología , Prostatitis/veterinaria , Neoplasias de la Corteza Suprarrenal/complicaciones , Neoplasias de la Corteza Suprarrenal/patología , Animales , Quistes/complicaciones , Quistes/patología , Hiperplasia/complicaciones , Hiperplasia/patología , Hiperplasia/veterinaria , Masculino , Prostatitis/complicaciones , Prostatitis/patología
10.
J Prosthet Dent ; 72(4): 351-4, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7990038

RESUMEN

The retention of amalgam and gallium alloy restorations in proximal box forms was measured in vitro, and three different adhesives to conventional undercuts were compared. For control, restorations were placed without undercuts or adhesives. No significant difference was found between amalgam and gallium alloys with each of the five methods of retention used. Alloys placed without retention or adhesives were significantly less retentive than all other groups. When Tytin alloy was used, no difference was found in retention among the restorations retained with Panavia or All-Bond adhesive or an occlusal dovetail and retention grooves, but Amalgambond adhesive was less retentive than all three of these methods. When gallium alloy was used, both Panavia and All-Bond adhesive were more retentive than undercuts, but the effect of Amalgambond adhesive was more retentive than undercuts, but the effect of Amalgambond adhesive was comparable to that of undercuts. The results of this study indicate that adhesives could be used in place of traditional undercuts to retain amalgam and gallium alloys, thus saving a considerable amount of tooth structure.


Asunto(s)
Adhesivos/química , Aleaciones Dentales/química , Amalgama Dental/química , Recubrimiento Dental Adhesivo , Restauración Dental Permanente , Galio/química , Cementos de Resina , Resinas Sintéticas/química , Grabado Ácido Dental , Resinas Compuestas/química , Preparación de la Cavidad Dental/clasificación , Preparación de la Cavidad Dental/métodos , Restauración Dental Permanente/clasificación , Restauración Dental Permanente/métodos , Recubrimientos Dentinarios/química , Humanos , Metacrilatos/química , Fosfatos/química , Estrés Mecánico , Propiedades de Superficie
11.
Eur J Biochem ; 212(3): 675-84, 1993 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-8462542

RESUMEN

The solution structure of a 55-amino-acid Kunitz-type proteinase inhibitor, ShPI, purified from the Caribbean sea anemone Stichodactyla helianthus, was determined by NMR spectroscopy. Nearly complete sequence-specific 1H-NMR assignments were obtained at pH 4.6 and 36 degrees C, and stereo-specific assignments were determined for 23 pairs of diastereotopic substituents. A data set of 666 upper distance limit constraints and 122 dihedral angle constraints collected on this basis was used as input for a structure calculation with the program DIANA. Following energy minimization with the program OPAL, the average root-mean-square diviation (RMSD) of the 20 DIANA conformers used to represent the solution structure relative to the mean structure is 61 pm for all backbone atoms N, C alpha and C', and 106 pm for all heavy atoms of residues 2-53. This high-quality solution structure of ShPI has a nearly identical molecular architecture as the bovine pancreatic trypsin inhibitor (BPTI), despite a mere 35% of sequence similarity between the two proteins. Exchange rates measured for 48 out of the 51 backbone amide protons showed that the positions of 20 slowly exchanging amide protons correlate well with hydrogen bonds involving these protons in the energy-minimized solution structure. The solution structure of ShPI is compared to the four homologous proteins for which the three-dimensional structure is also available.


Asunto(s)
Estructura Secundaria de Proteína , Anémonas de Mar , Inhibidor de la Tripsina de Soja de Kunitz/química , Secuencia de Aminoácidos , Animales , Espectroscopía de Resonancia Magnética/métodos , Modelos Moleculares , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Programas Informáticos , Soluciones , Inhibidor de la Tripsina de Soja de Kunitz/aislamiento & purificación
12.
Ginecol Obstet Mex ; 59: 246-8, 1991 Aug.
Artículo en Español | MEDLINE | ID: mdl-1765305

RESUMEN

Ten patients with isthmico-cervical leiomyoma as the only one localization, were surgically treated, from Jan, 1989 to May, 1990. It was 2.8% of all treated myomatosis. Average age was 42.4 years, with gestation of 1.1 per patients. Nine cases were treated by the abdominal via. One case presented with a recurrence. These cases represent a technico-surgical difficulty, due to tumor localization and size, as well as an ample knowledge about pelvic structures, in order to avoid digestive tract lesions, urinary and vascular. The present series confirms that this type of surgery is justified considering morbi-mortality, so it would be possible a definite histopathological evaluation.


Asunto(s)
Leiomioma , Neoplasias del Cuello Uterino , Adulto , Femenino , Humanos , Histerectomía , Leiomioma/epidemiología , Leiomioma/patología , Leiomioma/cirugía , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Prevalencia , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/cirugía
13.
Diabetologia ; 27(4): 482-3, 1984 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6439586

RESUMEN

Screening for red blood cell sorbitol dehydrogenase deficiency in 12 different mammalian species was performed. A wide inter-species variability in red cell sorbitol dehydrogenase with a virtually complete deficiency in pigs was observed. Aldose reductase and sorbitol dehydrogenase activities in 12 different pig tissues also were measured. Aldose reductase activity was present in all the tissues studied, whereas organ specificity for sorbitol dehydrogenase was observed. Sorbitol dehydrogenase activity was not detectable in lenses, among other tissues, making the pig a potential model for studies in experimental diabetes, particularly for the investigation of sorbitol dehydrogenase deficiency as a risk factor in the development of cataracts.


Asunto(s)
Diabetes Mellitus Experimental/enzimología , L-Iditol 2-Deshidrogenasa/deficiencia , Deshidrogenasas del Alcohol de Azúcar/deficiencia , Porcinos/metabolismo , Aldehído Reductasa/metabolismo , Animales , Bovinos , Cricetinae , Cabras , Caballos , L-Iditol 2-Deshidrogenasa/metabolismo , Mesocricetus , Ratones , Ratones Endogámicos BALB C , Especificidad de Órganos , Perisodáctilos , Conejos , Ratas , Ratas Endogámicas , Ovinos , Especificidad de la Especie
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...