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1.
Bull Environ Contam Toxicol ; 101(1): 14-19, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29858624

RESUMEN

The change towards intensive agriculture has led to an increase in the use of pesticides. In addition, legacy pesticides, such as organochlorines are still present in the environment. Ten Franciscana dolphins were accidentally killed by netting in a coastal area of Argentina in Buenos Aires province. From these animals, organochlorine, organophosphate and pyrethroid pesticides were analyzed in liver, bubbler and melon tissues. The concentrations of Σendosulfan ranged from not detectable values (nd) to 3539 ng g-1 lw, with the maximum level in melon tissue. DDE was present in 60% of all samples at concentrations from nd to 6672 ng g-1 lw, indicating historical DDT contamination. The presence of endosulfan and heptachlor in a nursling calf indicated a transfer of these pesticides through lactational and placental transport. The concentrations of organophosphates and pyrethroids were below the limit of detection, reflecting the low persistence of these compounds.


Asunto(s)
Delfines , Monitoreo del Ambiente , Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , Animales , Argentina , Endosulfano/análisis , Heptacloro/análisis , Hidrocarburos Clorados/análisis , Límite de Detección
2.
J Trace Elem Med Biol ; 50: 465-473, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29449107

RESUMEN

A complex network of regulatory proteins takes part in the mechanism underlying the radioresistance of Deinoccocus radiodurans bacterium (DR). The interaction of Mn(II) ions with DR-proteins and peptides seems to be responsible for proteins protection from oxidative damage induced by Reactive Oxygen Species during irradiation. In the present work we describe a combined approach of bioinformatic strategies based on structural data and annotation to predict the Mn(II)-binding proteins encoded by the genome of DR and, in parallel, the same predictions for other bacteria were performed; the comparison revealed that, in most of the cases, the content of Mn(II)-binding proteins is significantly higher in radioresistant than in radiosensitive bacteria. Moreover, we report the in silico protein-protein interaction network of the putative Mn(II)-proteins, remodeled in order to enhance the knowledge about the impact of Mn-binding proteins in DR ability to protect also DNA from various damaging agents such as ionizing radiation, UV radiation and oxidative stress.


Asunto(s)
Deinococcus/metabolismo , Manganeso/metabolismo , Proteoma/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Unión Proteica
3.
Phys Med ; 43: 140-147, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29195557

RESUMEN

The purpose of this work was to estimate the eye lens radiation exposure of the medical staff during interventional urology procedures. The measurements were carried out for six medical staff members performing 33 fluoroscopically-guided procedures. All procedures were performed with the X-ray tube positioned over the couch. The dose equivalents (Hp(0.07)) were measured at the eye level using optically stimulated luminescent (OSL) dosimeters and at the chest level with OSL dosimeters placed over the protective apron. The ratio of the dose measured close to the eye lens and on the chest was determined. The annual eye lens dose was estimated based on the workload in the service. For the physician and the instrumentalist nurse, the eye to chest dose ratios were 0.9±0.4 and 2.6±1.6 (k = 2), respectively. The average doses per procedure received by the eye lens were 78±24 µSv and 38±18 µSv, respectively. The eye lens dose per DAP was 8.4±17.5 µSv/(Gy·cm2) for the physician and 4.1±8.7 µSv/(Gy·cm2) for the instrumentalist nurse. The results indicate that the eye lens to chest dose ratio greatly varies according to the staff function and that the dose equivalent measured by the personal dosimeter worn on the chest may underestimate the eye lens dose of some medical staff members.


Asunto(s)
Personal de Salud , Cristalino/efectos de la radiación , Exposición Profesional/análisis , Exposición a la Radiación/análisis , Urología , Humanos , Rayos X
4.
Mar Pollut Bull ; 122(1-2): 446-449, 2017 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-28576598

RESUMEN

Otaria flavescens (SASL) and Arctocephalus australis (SAFS) are endemic of South America. The aims were to assess Cd concentrations in red blood cells (RBC) and plasma from free living females of both species; and to establish metallothioneins (MT) levels in blood fractions and the possible relationship between MTs and Cd. Blood of fifteen SASL and eight SAFS females from Isla de Lobos were analyzed (years 2010-2011). All animals showed Cd levels above the detection limit. Cd concentrations on SAFS were higher than those of SASL, however, no significant differences were observed on metal concentrations between cell fractions by species. Metal levels were associated with a natural presence and ecological-trophic habits of the prey items. On SASL the MT concentrations between fractions were similar; whereas, SAFS plasma concentrations were higher than RBC. The results reported constitute the first information on Cd and MT blood levels in these species.


Asunto(s)
Cadmio/sangre , Caniformia/fisiología , Metalotioneína/sangre , Contaminantes Químicos del Agua/sangre , Animales , Femenino , Metales , América del Sur , Zinc
5.
Exp Appl Acarol ; 56(4): 309-18, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22349941

RESUMEN

Although mitochondrial DNA mapping of Varroa destructor revealed the presence of several haplotypes, only two of them (Korean and Japanese haplotypes) were capable to infest Apis mellifera populations. Even though the Korean haplotype is the only one that has been reported in Argentina, these conclusions were based on mites sampled in apiaries from a specific geographical place (Buenos Aires province). To study mites from several sites of Argentina could reveal the presence of the Japanese genotype, especially considering sites near to Brazil, where Japanese haplotype was already detected. The aim of this work was to study the genetic structure of V. destructor populations from apiaries located in various provinces of Argentina, in order to determine the presence of different haplotypes. The study was carried out between January 2006 and December 2009. Phoretic adult Varroa mites were collected from honey bee workers sampled from colonies of A. mellifera located in Entre Ríos, Buenos Aires, Corrientes, Río Negro, Santa Cruz and Neuquén provinces. Twenty female mites from each sampling site were used to carry out the genetic analysis. For DNA extraction a nondestructive method was used. DNA sequences were compared to Korean haplotype (AF106899) and Japanese haplotype (AF106897). All DNA sequences obtained from mite populations sampled in Argentina, share 98% of similitude with Korean Haplotype (AF106899). Taking into account these results, we are able to conclude that Korean haplotype is cosmopolite in Argentina.


Asunto(s)
Abejas/parasitología , Varroidae/genética , Animales , Secuencia de Bases , ADN Mitocondrial/química , ADN Mitocondrial/genética , Complejo IV de Transporte de Electrones/química , Complejo IV de Transporte de Electrones/genética , Femenino , Variación Genética , Haplotipos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Alineación de Secuencia , Análisis de Secuencia de ADN , Varroidae/enzimología
6.
Mol Hum Reprod ; 16(7): 481-91, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20231161

RESUMEN

Cyclic adenosine 3'-5'-monophosphate (cAMP) is a second messenger, which exerts an important role in the control of human first-trimester trophoblast functions. In the present study we demonstrate the existence of a mechanism that is able to extrude cAMP from trophoblast-derived cell lines, and show evidence indicating the involvement of multidrug resistance protein (MRP) 1, a transporter belonging to the ATP-binding cassette family, in cAMP egress. MRP1 is expressed in trophoblast cell lines and cAMP efflux is highly reduced by the MRP1 inhibitor, MK-571. In addition, interleukin-1beta and estrone are able to enhance MRP1 gene expression and influence extracellular cAMP concentration. The occurrence of a MRP1-dependent cAMP efflux is also shown in human first-trimester placenta explants. Extracellular cAMP could represent a source for adenosine formation, which in turn could regulate cAMP-dependent responses in placental tissue. Evidence is provided that adenosine receptor subtypes are present and functional in human trophoblast-derived cells. A role for cAMP egress mechanism in the fine modulation of the nucleotide homeostasis is therefore suggested.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , AMP Cíclico/metabolismo , Trofoblastos/metabolismo , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Línea Celular Tumoral , Células Cultivadas , Colforsina/farmacología , Estrona/farmacología , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Técnicas In Vitro , Interleucina-1beta/farmacología , Placenta/metabolismo , Embarazo , Probenecid/farmacología , Progesterona/farmacología , Propionatos/farmacología , Quinolinas/farmacología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Trofoblastos/efectos de los fármacos
7.
Bol. Asoc. Argent. Odontol. Niños ; 37(2/3): 21-26, jun.-sept. 2008. tab, graf
Artículo en Español | LILACS | ID: lil-526553

RESUMEN

Los pacientes VIH+ constituyen un grupo de alto riesgo de caries. Poco se conoce acerca de los componentes proteicos salivales en pacientes pediátricos VIH+ y su relación con el riesgo cariogénico. Los objetivos del trabajo fueron: a. Determinar el nivel proteico salival en pacientes pediátricos VIH+; b. Caracterizar dicho componente; c. Correlacionarlo con el estado dentario. Utilizamos un diseño descriptivo transversal caso-control. 11 pacientes pediátricos (4-12 años) VIH+ de ambos sexos, conformaron el grupo caso y 16 VIH- el grupo control. Determinamos el flujo salival estimulado y no estimulado (expectoración-cronometría), el pH (potenciometría), la capacidad buffer (titulación), el nivel proteico salival (método de Bradford) y el recuento de S grupo mutans (Gold et al., 1973). Identificamos los componentes salivales (5-120 kDa) por electroforesis vertical (SDS PAGE, Laemli et al., 1970). El examen dentario fue realizado por 3 operadores calibrados. Tomamos el componente C +c como índice del estado dentario. Calculamos la media y ES de las variables en estudio. Utilizamos la prueba t de Student para establecer diferencias entre medias (p<0.05) y el coeficiente r de Pearson para correlacionar el nivel proteico salival con el estado dentario. El componente C+c fue significativamente mayor (t=2.27, p=0.03) en pacientes VIH+ (14.0 +-3.5 vs. 8.6 +-7.3) al igual que el nivel proteico salival (4.68 +- 1.21 vs. 3.8 +- 0.7 mg/mL, t=2.39, p=0.02), y el flujo salival no estimulado resultó menor (0.33 +- 0.08 vs. 0.49 +-0.08 mL/min, t=2.23, p=0.034). Las restantes variables no resultaron significativamente diferentes. Identificamos componentes proteicos de 12, 45 y 80 KDa en pacientes VIH+, compatibles con SLPI, anhidrasa carbónica isoenzima VI, lactoferrina y lactoperoxidasa. Concluimos que la prevalencia de caries en pacientes pediátricos VIH+ es una función compleja que involucra a la fracción proteica salival alterando su funcionalidad.


Asunto(s)
Humanos , Masculino , Adolescente , Adulto , Niño , Femenino , Atención Dental para Enfermos Crónicos/métodos , Atención Dental para Niños/métodos , Susceptibilidad a Caries Dentarias , Infecciones por VIH/complicaciones , Proteínas y Péptidos Salivales/fisiología , Argentina/epidemiología , Factores de Riesgo , Interpretación Estadística de Datos
8.
Placenta ; 29(8): 660-70, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18617261

RESUMEN

We have tested the hypothesis that human early trophoblast is a target for somatostatin (SRIF) regulatory actions. We report for the first time that SSTR2A and 2B transcripts and proteins are present in first-trimester human chorionic villi and the trophoblast-derived HTR-8/SVneo and JAR cells. In both cell lines, SSTR are functional since SRIF inhibits cyclic AMP pathway, stimulates arachidonic acid release and enhances cell proliferation. Moreover, in HTR-8/SVneo cells, considered a good model of first-trimester EVT, SRIF also enhances migration. An involvement of the cyclic AMP pathway in mediating SRIF effects on proliferation and migration is suggested. Our data support the idea that SRIF regulates early trophoblast functions mainly through an interaction with SSTR2.


Asunto(s)
Primer Trimestre del Embarazo/fisiología , Somatostatina/fisiología , Trofoblastos/fisiología , Diferenciación Celular/genética , Proliferación Celular , Células Cultivadas , AMP Cíclico/metabolismo , Femenino , Humanos , Embarazo , Primer Trimestre del Embarazo/genética , Primer Trimestre del Embarazo/metabolismo , Receptores de Somatostatina/genética , Receptores de Somatostatina/metabolismo , Receptores de Somatostatina/fisiología , Somatostatina/metabolismo , Trofoblastos/metabolismo
9.
Mol Hum Reprod ; 13(1): 77-83, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17092984

RESUMEN

Vitamin C plays an important role in embryogenesis and fetal growth as well as in the progression of pregnancy and delivery. Therefore, it is important to understand the mechanism that mediates its transport to the fetus as well as the possible influences by endogenous and exogenous substances on its placental uptake. The aim of this study was to investigate placental sodium-dependent vitamin C transporters (SVCT) 1 and 2. By means of RT-PCR, we found that SVCT2, but not SVCT1, mRNA is expressed in human trophoblast cell line HTR-8/SVneo. Our method was able to confirm SVCT2 mRNA expression in human first-trimester chorionic villi but not in term placental tissue. Cell line kinetic studies of [(14)C] ascorbic acid (AA) uptake indicated a one-site model and a saturable process. Fetal bovine serum (FBS) and epidermal growth factor (EGF) do not influence the transport properties, although they significantly increase the expression of SVCT2. Steroid hormones (17beta-estradiol, progesterone and cortisol), flavonoids (genistein and quercetin) and non-steroidal anti-inflammatory drugs (NSAIDs) (indomethacin and diclofenac) inhibit [(14)C]AA uptake in a dose-dependent and non-competitive manner. On the contrary, the process is not influenced by aspirin. Our study suggests the use of HTR-8/SVneo cells as a suitable model for trophoblast vitamin C transport investigation.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Flavonoides/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Transportadores de Anión Orgánico Sodio-Dependiente/genética , Esteroides/farmacología , Simportadores/genética , Trofoblastos/metabolismo , Ácido Ascórbico/farmacocinética , Radioisótopos de Carbono/farmacocinética , Línea Celular , Femenino , Humanos , Modelos Biológicos , Transportadores de Anión Orgánico Sodio-Dependiente/metabolismo , Embarazo , Primer Trimestre del Embarazo/metabolismo , ARN Mensajero/metabolismo , Transportadores de Sodio Acoplados a la Vitamina C , Simportadores/metabolismo , Nacimiento a Término/metabolismo
11.
Appl Ergon ; 31(3): 317-22, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10855455

RESUMEN

An ergonomic approach could improve the quality of life and activities in daily living. Gerontechnology reduces the effects of age-related impairments with technological devices and particular design for the home-environment. Physiological decline with increasing age renders the daily activities at home more difficult. This paper highlights some "common sense" and specific design suggestions in the entrance and kitchen, aimed to increase the self-sufficiency of elderly people. We suggest that gerontechnology may have a particular role in the improvement of comfort and safety for aged people.


Asunto(s)
Actividades Cotidianas , Planificación Ambiental , Ergonomía , Anciano Frágil , Calidad de Vida , Anciano , Envejecimiento/fisiología , Geriatría , Humanos , Movimiento/fisiología , Postura/fisiología , Tecnología
13.
Age Ageing ; 26(5): 339-44, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9351477

RESUMEN

Gerontology is the scientific study of the ageing process and special problems of aged people. Ergonomics is an applied science for optimizing performance and productivity and reducing the risks of injury, discomfort and illness. Gerontechnology is concerned with fundamental and applied research on the complex interaction of elderly people with technological products and the built environment. It has the potential to improve the capability of people confronted by the challenges of ageing. We suggest that gerontechnology may have a particular role in relation to the reduction of visual acuity, and can improve the comfort and safety of older people.


Asunto(s)
Planificación Ambiental , Ergonomía , Anciano Frágil , Presbiopía/rehabilitación , Baja Visión/rehabilitación , Heridas y Lesiones/prevención & control , Anciano , Evaluación Geriátrica , Humanos , Investigación , Seguridad , Agudeza Visual
14.
Riv Eur Sci Med Farmacol ; 18(4): 153-6, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-9177614

RESUMEN

This brief commentary is focused on the experimental procedures employed in the evaluation of both cognitive and balance impairments of aging patients. This is an important ergonomic issue that might be used for research purposes. In fact, the corrected assessment of impairments during aging may favor the development of new integrated ergonomic strategies to ameliorate ADL together with the reduction of environmental risks.


Asunto(s)
Envejecimiento/fisiología , Cognición/fisiología , Ergonomía , Pruebas Neuropsicológicas , Equilibrio Postural/fisiología , Actividades Cotidianas , Anciano , Humanos
15.
Thorac Cardiovasc Surg ; 36(2): 89-95, 1988 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3388409

RESUMEN

Twenty large white pigs underwent normothermic right ventricular bypass, pulmonary artery valve excision and right ventricular outflow tract (RVOT) reconstruction using a synthetic material (Mitrathane). The animals were divided in two groups (ten for each group) for the RVOT reconstruction model: Group I with a composite monocusp patch (with a new design geometrically related to pulmonary artery circumference) and Group II without a valve mechanism. Four early postoperative deaths occurred in Group I (unrelated to monocusp patch function) and seven in Group II (due to acute right ventricular failure). Follow up of the six animals of Group I was 600-630 (average 617.5) days and of the three Group II animals was 95-110 (average 101.6) days. In Group I haemodynamic studies showed no significant difference from preoperative values at 5 months while at 20 months there was a moderate valve insufficiency in all animals. In Group II severe right ventricular insufficiency was present in all animals and spontaneous death occurred after about 3 months. In Group I angiographic studies disclosed no evidence of graft calcification or stenosis while in Group II there was a moderate pulmonary trunk dilatation. Post mortem examination showed no signs of degeneration in any graft. Microscopic studies of both groups revealed an acellular layer of fibrin on the external surface and fibrous deposit on the inner part of the suture with the right ventricle. In Group I there were leukocyte and histocyte infiltration of the grafts. In these experiments our synthetic monocusp model showed good function and durability in comparison to a RVOT reconstruction without a valve mechanism.


Asunto(s)
Prótesis Vascular , Poliuretanos , Obstrucción del Flujo Ventricular Externo/cirugía , Animales , Prótesis Valvulares Cardíacas , Hemodinámica , Diseño de Prótesis , Porcinos
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