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1.
J Environ Manage ; 261: 110164, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148260

RESUMEN

A methodology to evaluate groundwater vulnerability was developed and tested in a case study in the Central Valleys of the state of Oaxaca, Mexico, a region known for intensive agricultural activities and poor water management policies. An analysis was conducted to create and evaluate scenarios reflecting anthropogenic and natural stressors on groundwater using an analytical hierarchy process (AHP) and geographic information systems. Uncertainty in the vulnerability model was assessed using a Monte Carlo analysis. Five indices (abstraction (Abs), pollution (Po), runoff (Ru), groundwater recharge (Re), and marginalization (Ma)) were selected after an evaluation of the effects of population growth, climatology, hydrogeological features, and social marginalization on access to groundwater. Abstraction, pollution, and recharge rates are the main drivers of groundwater vulnerability, accounting for 87% of the vulnerability. The analysis revealed that the proposed model generates consistent results and contains low uncertainty. It also showed that more than 50% of the region's groundwater is moderately, and the vulnerability has become increasingly with abstraction, reduced recharge, and pollution (the most sensitive indices), indicating that groundwater in the Central Valleys is under great stress. Pollution and abstraction of groundwater resources are expected to rise in the more vulnerable areas, which will increase water crises and reduce access to water in rural communities. The approach and the indicators establish a baseline for the management and protection of water resources in developing countries where high-resolution data are lacking.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Agricultura , Monitoreo del Ambiente , México , Abastecimiento de Agua
2.
Braz J Med Biol Res ; 52(10): e8491, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31618368

RESUMEN

Considering the recognized role of thyroid hormones on the cardiovascular system during health and disease, we hypothesized that type 2 deiodinase (D2) activity, the main activation pathway of thyroxine (T4)-to-triiodothyronine (T3), could be an important site to modulate thyroid hormone status, which would then constitute a possible target for ß-adrenergic blocking agents in a myocardial infarction (MI) model induced by left coronary occlusion in rats. Despite a sustained and dramatic fall in serum T4 concentrations (60-70%), the serum T3 concentration fell only transiently in the first week post-infarction (53%) and returned to control levels at 8 and 12 weeks after surgery compared to the Sham group (P<0.05). Brown adipose tissue (BAT) D2 activity (fmol T4·min-1·mg ptn-1) was significantly increased by approximately 77% in the 8th week and approximately 100% in the 12th week in the MI group compared to that of the Sham group (P<0.05). Beta-blocker treatment (0.5 g/L propranolol given in the drinking water) maintained a low T3 state in MI animals, dampening both BAT D2 activity (44% reduction) and serum T3 (66% reduction in serum T3) compared to that of the non-treated MI group 12 weeks after surgery (P<0.05). Propranolol improved cardiac function (assessed by echocardiogram) in the MI group compared to the non-treated MI group by 40 and 57%, 1 and 12 weeks after treatment, respectively (P<0.05). Our data suggested that the beta-adrenergic pathway may contribute to BAT D2 hyperactivity and T3 normalization after MI in rats. Propranolol treatment maintained low T3 state and improved cardiac function additionally.


Asunto(s)
Tejido Adiposo Pardo/metabolismo , Antagonistas Adrenérgicos beta/administración & dosificación , Yoduro Peroxidasa/metabolismo , Infarto del Miocardio/metabolismo , Propranolol/administración & dosificación , Tiroxina/sangre , Triyodotironina/sangre , Tejido Adiposo Pardo/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Yoduro Peroxidasa/efectos de los fármacos , Masculino , Ratas , Ratas Wistar , Tiroxina/efectos de los fármacos , Triyodotironina/efectos de los fármacos , Yodotironina Deyodinasa Tipo II
3.
Braz. j. med. biol. res ; 52(10): e8491, 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1039254

RESUMEN

Considering the recognized role of thyroid hormones on the cardiovascular system during health and disease, we hypothesized that type 2 deiodinase (D2) activity, the main activation pathway of thyroxine (T4)-to-triiodothyronine (T3), could be an important site to modulate thyroid hormone status, which would then constitute a possible target for β-adrenergic blocking agents in a myocardial infarction (MI) model induced by left coronary occlusion in rats. Despite a sustained and dramatic fall in serum T4 concentrations (60-70%), the serum T3 concentration fell only transiently in the first week post-infarction (53%) and returned to control levels at 8 and 12 weeks after surgery compared to the Sham group (P<0.05). Brown adipose tissue (BAT) D2 activity (fmol T4·min-1·mg ptn-1) was significantly increased by approximately 77% in the 8th week and approximately 100% in the 12th week in the MI group compared to that of the Sham group (P<0.05). Beta-blocker treatment (0.5 g/L propranolol given in the drinking water) maintained a low T3 state in MI animals, dampening both BAT D2 activity (44% reduction) and serum T3 (66% reduction in serum T3) compared to that of the non-treated MI group 12 weeks after surgery (P<0.05). Propranolol improved cardiac function (assessed by echocardiogram) in the MI group compared to the non-treated MI group by 40 and 57%, 1 and 12 weeks after treatment, respectively (P<0.05). Our data suggested that the beta-adrenergic pathway may contribute to BAT D2 hyperactivity and T3 normalization after MI in rats. Propranolol treatment maintained low T3 state and improved cardiac function additionally.


Asunto(s)
Animales , Masculino , Ratas , Propranolol/administración & dosificación , Tiroxina/sangre , Tejido Adiposo Pardo/metabolismo , Agonistas Adrenérgicos beta/administración & dosificación , Yoduro Peroxidasa/metabolismo , Infarto del Miocardio/metabolismo , Tiroxina/efectos de los fármacos , Triyodotironina/efectos de los fármacos , Triyodotironina/sangre , Tejido Adiposo Pardo/efectos de los fármacos , Ratas Wistar , Modelos Animales de Enfermedad , Yoduro Peroxidasa/efectos de los fármacos
4.
World J Plast Surg ; 7(2): 166-170, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-30083498

RESUMEN

BACKGROUND: Little is known about educational games in Plastic Surgery training. Pecha kucha game has proved to be helpful tool to improve communicative skills. This study survey in resident participants in Pecha Kucha contest assessed how to improve speaking skills in plastic surgery training. METHODS: In the second edition of Pecha Kucha contest of the Mexican Society of Plastic Surgery, a survey was conducted with the residents to know the utility of this educational game. RESULTS: Twenty-six residents participated in the survey. Most of them from the Universidad Nacional Autonoma de México. Most of the residents considered it to be a good tool in order to improve communication skills and helpful for their future practice. The amount of time to present an idea was considered enough to express an idea. The most common proportion between words and images was 20-80% in the presentation. CONCLUSION: Pecha Kucha helped to improve communication skills during residents' training. We encourage other plastic surgery societies to incorporate educational games in their national and international meetings.

5.
Science ; 351(6270): 257-60, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26816375

RESUMEN

We report the discovery of ASASSN-15lh (SN 2015L), which we interpret as the most luminous supernova yet found. At redshift z = 0.2326, ASASSN-15lh reached an absolute magnitude of Mu ,AB = -23.5 ± 0.1 and bolometric luminosity Lbol = (2.2 ± 0.2) × 10(45) ergs s(-1), which is more than twice as luminous as any previously known supernova. It has several major features characteristic of the hydrogen-poor super-luminous supernovae (SLSNe-I), whose energy sources and progenitors are currently poorly understood. In contrast to most previously known SLSNe-I that reside in star-forming dwarf galaxies, ASASSN-15lh appears to be hosted by a luminous galaxy (MK ≈ -25.5) with little star formation. In the 4 months since first detection, ASASSN-15lh radiated (1.1 ± 0.2) × 10(52) ergs, challenging the magnetar model for its engine.

6.
Nature ; 523(7559): 189-92, 2015 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-26156372

RESUMEN

A new class of ultra-long-duration (more than 10,000 seconds) γ-ray bursts has recently been suggested. They may originate in the explosion of stars with much larger radii than those producing normal long-duration γ-ray bursts or in the tidal disruption of a star. No clear supernova has yet been associated with an ultra-long-duration γ-ray burst. Here we report that a supernova (SN 2011kl) was associated with the ultra-long-duration γ-ray burst GRB 111209A, at a redshift z of 0.677. This supernova is more than three times more luminous than type Ic supernovae associated with long-duration γ-ray bursts, and its spectrum is distinctly different. The slope of the continuum resembles those of super-luminous supernovae, but extends further down into the rest-frame ultraviolet implying a low metal content. The light curve evolves much more rapidly than those of super-luminous supernovae. This combination of high luminosity and low metal-line opacity cannot be reconciled with typical type Ic supernovae, but can be reproduced by a model where extra energy is injected by a strongly magnetized neutron star (a magnetar), which has also been proposed as the explanation for super-luminous supernovae.

7.
Hum Reprod ; 29(10): 2269-77, 2014 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-25124667

RESUMEN

STUDY QUESTION: Is there a relationship between decidualization and apoptosis of decidual stromal cells (DSC)? SUMMARY ANSWER: Decidualization triggers the secretion of soluble factors that induce apoptosis in DSC. WHAT IS KNOWN ALREADY: The differentiation and apoptosis of DSC during decidualization of the receptive decidua are crucial processes for the controlled invasion of trophoblasts in normal pregnancy. Most DSC regress in a time-dependent manner, and their removal is important to provide space for the embryo to grow. However, the mechanism that controls DSC death is poorly understood. STUDY DESIGN, SIZE, DURATION: The apoptotic response of DSC was analyzed after exposure to different exogenous agents and during decidualization. The apoptotic potential of decidualized DSC supernatants and prolactin (PRL) was also evaluated. PARTICIPANTS/MATERIALS, SETTING, METHODS: DSC lines were established from samples of decidua from first trimester pregnancies. Apoptosis was assayed by flow cytometry. PRL production, as a marker of decidualization, was determined by enzyme-linked immunosorbent assay. MAIN RESULTS AND THE ROLE OF CHANCE: DSCs were resistant to a variety of apoptosis-inducing substances. Nevertheless, DSC underwent apoptosis during decidualization in culture, with cAMP being essential for both apoptosis and differentiation. In addition, culture supernatants from decidualized DSC induced apoptosis in undifferentiated DSC, although paradoxically these supernatants decreased the spontaneous apoptosis of decidual lymphocytes. Exogenously added PRL did not induce apoptosis in DSC and an antibody that neutralized the PRL receptor did not decrease the apoptosis induced by supernatants. LIMITATIONS, REASONS FOR CAUTIONS: Further studies are needed to examine the involvement of other soluble factors secreted by decidualized DSC in the induction of apoptosis. WIDER IMPLICATIONS OF THE FINDINGS: The present results indicate that apoptosis of DSC occurs in parallel to differentiation, in response to decidualization signals, with soluble factors secreted by decidualized DSC being responsible for triggering cell death. These studies are relevant in the understanding of how the regression of decidua, a crucial process for successful pregnancy, takes place. STUDY FUNDING/COMPETING INTERESTS: This work was supported by the Consejería de Economía, Innovación y Ciencia, Junta de Andalucía (Grant CTS-6183, Proyectos de Investigación de Excelencia 2010 to C.R.-R.) and the Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, Spain (Grants PS09/00339 and PI12/01085 to E.G.O.). E.L.-D. was supported by fellowships from the Ministerio de Educación y Ciencia, Spain and the University of Granada. The authors have no conflict of interest.


Asunto(s)
Apoptosis , AMP Cíclico/metabolismo , Decidua/metabolismo , Células del Estroma/metabolismo , Diferenciación Celular , Línea Celular Tumoral , AMP Cíclico/fisiología , Decidua/citología , Decidua/crecimiento & desarrollo , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Humanos , Células Jurkat , Prolactina/metabolismo , Células del Estroma/citología
8.
Neurotox Res ; 26(2): 115-29, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24549503

RESUMEN

Methamphetamine (METH) causes significant loss of some striatal projection and interneurons. Recently, our group reported on the proliferation of new cells 36 h after METH and some of the new cells survive up to 12 weeks (Tulloch et al., Neuroscience 193:162-169, 2011b). We hypothesized that some of these cells will differentiate and express striatal neuronal phenotypes. To test this hypothesis, mice were injected with METH (30 mg/kg) followed by a single BrdU injection (100 mg/kg) 36 h after METH. One week after METH, a population of BrdU-positive cells expressed the neuronal progenitor markers nestin (18 %) and ß-III-tubulin (30 %). At 8 weeks, 14 % of the BrdU-positive cells were also positive for the mature neuron marker, NeuN. At 12 weeks, approximately 7 % of the BrdU-positive cells co-labeled with ChAT, PV or DARPP-32. We measured motor coordination on the rotarod and psychomotor activity in the open-field. At 12 weeks, METH-injected mice exhibited delayed motor coordination deficits. In contrast, open-field tests revealed that METH-injected mice compared to saline mice displayed psychomotor deficits at 2.5 days but not at 2 or more weeks after METH. Taken together, these data demonstrate that some of the new cells generated in the striatum differentiate and express the phenotypes of striatal neurons. However, the proportion of these new neurons is low compared to the proportion that died by apoptosis 24 h after the METH injection. More studies are needed to determine if the new neurons are functional.


Asunto(s)
Estimulantes del Sistema Nervioso Central/farmacología , Cuerpo Estriado/efectos de los fármacos , Metanfetamina/farmacología , Actividad Motora/efectos de los fármacos , Neurogénesis/efectos de los fármacos , Neuronas/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Colina O-Acetiltransferasa/metabolismo , Cuerpo Estriado/fisiología , Proteínas de Unión al ADN , Fosfoproteína 32 Regulada por Dopamina y AMPc/metabolismo , Conducta Exploratoria/efectos de los fármacos , Conducta Exploratoria/fisiología , Masculino , Ratones Endogámicos ICR , Actividad Motora/fisiología , Proteínas del Tejido Nervioso/metabolismo , Nestina/metabolismo , Células-Madre Neurales/efectos de los fármacos , Células-Madre Neurales/fisiología , Neurogénesis/fisiología , Neuronas/fisiología , Proteínas Nucleares/metabolismo , Parvalbúminas/metabolismo , Tubulina (Proteína)/metabolismo
9.
Hum Reprod ; 27(9): 2775-84, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22718279

RESUMEN

BACKGROUND: Decidual stromal cells (DSCs) have classically been considered fibroblastic cells, although their function, cell lineage and origin are not fully understood. We previously demonstrated that human DSCs showed similarities with follicular dendritic cells (FDCs): DSCs expressed FDC-associated antigens, both types of cells are contractile and both are related to mesenchymal stem cells (MSCs). To further characterize DSCs, we investigated whether DSCs and FDCs share any distinctive phenotypical and functional characteristics. METHODS: Human FDC lines were obtained from tonsillectomy samples, human DSC lines from elective termination of pregnancy samples and human MSC lines from bone marrow aspirates. We isolated DSC, FDC and MSC lines and compared their characteristics with flow cytometry and enzyme-linked immunosorbent assay. Cell lines were cultured with tumour necrosis factor (TNF) and lymphotoxin (LT)α(1)ß(2), cytokines involved in FDC differentiation. Cell lines were also differentiated in culture after exposure to progesterone and cAMP, factors involved in the differentiation (decidualization) of DSC. RESULTS: Like MSCs, DSCs and FDCs expressed MSC-associated antigens (CD10, CD29, CD54, CD73, CD106, α-smooth muscle actin and STRO-1) and lacked CD45 expression, and all three types of cell line showed increased expression of CD54 (ICAM-1) and CD106 (VCAM-1) when cultured TNF and LTα(1)ß(2). DSCs and FDCs, however, exhibited characteristics not observed in MSCs: DSCs expressed FDC-associated antigens CD14, CD21 and CD23, B cell-activating factor and secreted C-X-C motif chemokine 13. Moreover, DSC lines but not MSC lines inhibited the spontaneous apoptosis of B lymphocytes, a typical functional attribute of FDC. During culture with progesterone and cAMP, FDCs, like DSCs but in contrast to MSCs, changed their morphology from a fibroblastic to a rounder shape, and cells secreted prolactin. CONCLUSIONS: Our results suggest that DSCs and FDCs share a common precursor in MSCs but this precursor acquires new capacities when it homes to peripheral tissues. We discuss these shared properties in the context of immune-endocrine regulation during pregnancy.


Asunto(s)
Apoptosis , Factor Activador de Células B/metabolismo , Linfocitos B/citología , Quimiocina CXCL13/biosíntesis , Decidua/metabolismo , Decidua/fisiología , Células del Estroma/citología , Adulto , Células de la Médula Ósea/citología , Línea Celular , Células Cultivadas , Niño , Preescolar , Citocinas/metabolismo , Femenino , Fibroblastos/citología , Humanos , Masculino , Células Madre Mesenquimatosas/citología , Fenotipo , Embarazo
10.
Placenta ; 33(4): 257-63, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22261157

RESUMEN

BACKGROUND: Normal pregnancy and spontaneous abortion in humans and mice are associated with immune responses. The decidua harbors dendritic cells identifiable in humans by their expression of DC-SIGN. Because dendritic cells are essential for immune response regulation, decidual DC-SIGN+ cells may play a role in normal or pathological pregnancy outcomes. Previous reports suggested that DC interact with NK cells in decidua, although the functional significance of this phenomenon remains unknown. OBJECTIVE: We studied the presence of conjugates of DC-SIGN+ cells with CD56+ NK cells in normal human decidua. METHODS: Conjugates of DC-SIGN+ cells with CD56+ NK cells were studied in leukocyte suspensions of normal human decidua (6-11 weeks) by flow cytometry and confocal microscopy. The presence of apoptotic cells was determined by the TUNEL assay, incubation with annexin V and confocal microscopy in decidual leukocyte suspensions and by the TUNEL assay in decidual sections. RESULTS: We observed conjugates of decidual DC-SIGN+ cells with CD56+ NK cells (40.2±26.1% of all the DC-SIGN+ cells by flow cytometry and 52.3±10.2% by confocal microscopy). We also found that a proportion of DC-SIGN+ cells were in apoptosis, since they were TUNEL+ (40.2±7.2% of all DC-SIGN+ cells in decidual sections) and annexin V+ (34.4±15.2% in leukocyte suspensions). And sorted DC-SIGN+ cells had multilobulated nuclei. CONCLUSIONS: The conjugates of decidual DC-SIGN+ cells with CD56+ NK cells strongly suggest that these latter cells induce apoptosis in DC-SIGN+ cells during normal pregnancy. We discuss this possibility in the context of maternal-fetal tolerance.


Asunto(s)
Apoptosis , Decidua/inmunología , Células Dendríticas/inmunología , Células Asesinas Naturales/inmunología , Mantenimiento del Embarazo , Embarazo/inmunología , Adulto , Anexina A5/metabolismo , Antígeno CD56/metabolismo , Adhesión Celular , Moléculas de Adhesión Celular/metabolismo , Forma del Núcleo Celular , Decidua/citología , Decidua/metabolismo , Células Dendríticas/citología , Células Dendríticas/metabolismo , Femenino , Citometría de Flujo , Humanos , Etiquetado Corte-Fin in Situ , Células Asesinas Naturales/citología , Células Asesinas Naturales/metabolismo , Lectinas Tipo C/metabolismo , Microscopía Confocal , Microscopía Fluorescente , Embarazo/metabolismo , Primer Trimestre del Embarazo , Receptores de Superficie Celular/metabolismo , Adulto Joven
11.
Placenta ; 32(1): 86-95, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21126763

RESUMEN

BACKGROUND: It has been demonstrated that human umbilical cord stromal stem cells (UCSSCs) are bio-equivalent to bone marrow mesenchymal stem cells. However, little is known about their tissue origin or in vivo functions, and data on their expansion properties are limited due to early senescence in the culture methods described to date. METHODS: UC sections and cultured UCSSCs were analyzed with a panel of 12 antibodies. UCSSCs were grown in low-FCS containing medium at 5% or 21% oxygen and were assayed for their clonogenic properties, karyotype stability, expression of specific cellular markers, and multi-lineage potential. UCSSC contractile properties were evaluated by using collagen gel contraction assays under cytokine stimulus. RESULTS: Immunohistochemistry studies showed that the UCSSCs were derived from the Wharton's jelly and not from the vascular smooth muscle sheath of the blood vessels. UCSSC growth properties were increased in a 5% oxygen atmosphere in comparison to normoxic culture conditions. In both culture conditions, UCSSCs were CD14-, CD34-, and CD45-negative while expressing high levels of CD73, CD90 and CD105 and maintaining their differentiation potentialities. UCSSCs expressed alpha smooth muscle actin and behaved as functional myofibroblasts when cellular contraction was challenged with appropriate stimuli. CONCLUSIONS: UCSCs are mesenchymal stem cells that reside in the perivascular area of Wharton's jelly and are phenotypically and functionally related to myofibroblasts.


Asunto(s)
Neprilisina/metabolismo , Células del Estroma/metabolismo , Células del Estroma/fisiología , Resistencia a la Tracción/fisiología , Cordón Umbilical/metabolismo , Cordón Umbilical/fisiología , Hipoxia de la Célula , Fenómenos Fisiológicos Celulares , Proliferación Celular , Células Cultivadas , Elasticidad , Citometría de Flujo , Humanos , Inmunohistoquímica , Cordón Umbilical/citología
12.
Placenta ; 31(11): 1019-22, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20934749

RESUMEN

Recent studies showed that some functions of decidual dendritic cells appear to be essential for pregnancy. In humans, decidual dendritic cells are identifiable by their expression of DC-SIGN. We compared the subpopulations of human decidual DC-SIGN+ cells from first-trimester normal pregnancies and spontaneous abortions by flow cytometry. In normal decidua, DC-SIGN+ cells expressed antigens associated with immature myeloid dendritic cells. In samples from spontaneous abortions, we detected decidual DC-SIGN+ cells with an antigen phenotype equivalent to that of DC-SIGN+ cells from normal pregnancies, but at a significantly lower proportion (P < 0.01). Our results support the hypothesis that dendritic cells play a role in normal or pathological human pregnancy outcomes.


Asunto(s)
Aborto Espontáneo/fisiopatología , Moléculas de Adhesión Celular/metabolismo , Decidua/citología , Células Dendríticas/metabolismo , Lectinas Tipo C/metabolismo , Receptores de Superficie Celular/metabolismo , Aborto Espontáneo/inmunología , Adulto , Antígenos de Superficie/metabolismo , Recuento de Células , Decidua/inmunología , Decidua/metabolismo , Femenino , Citometría de Flujo , Humanos , Inmunofenotipificación , Leucocitos/metabolismo , Células Mieloides/metabolismo , Embarazo , Primer Trimestre del Embarazo , Adulto Joven
13.
J Virol ; 84(22): 11916-28, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20810724

RESUMEN

The infectious salmon anemia virus (ISAV), an orthomyxovirus, is the major cause of outbreaks of high mortality rates in salmon in Chile. It has been proposed that the virulence of ISAV isolates lies mainly in hemagglutinin-esterase and fusion glycoproteins. However, based on current information, the contribution of other viral genes cannot be ruled out. To study this, we isolated and determined the complete coding sequence of two high-prevalence Chilean isolates associated with outbreaks of high mortality rates: ISAV752_09 and ISAV901_09. These isolates were compared to 15 Norwegian isolates that exhibit differences in their virulence. For this purpose, we performed bioinformatic analyses of (i) functional domains, (ii) specific mutations, (iii) Bayesian phylogenetics, and (iv) structural comparisons between ISAV and influenza virus glycoproteins by using molecular modeling. Phylogenetic analysis shows two genogroups for each protein, one of them containing the Chilean isolates. The gene sequence of the polymerase complex and nucleoprotein indicated that they are closely related to homologues from highly pathogenic Norwegian viruses. Notably, seven of the eight mutations that are present only in the Chilean isolates are on the polymerase complex and nucleoprotein. Structural modeling of hemagglutinin-esterase shows patches of variable residues on its surface. Fusion protein modeling shows that insertions are flexible regions that could affect proteolytic processing, increasing either the accessibility or the number of recognition sites for specific proteases. We found antigenic drift processes related to insertion into the isolated segment 5 of the ISAV752_09. Our results confirm the European origin of Chilean isolates to be the result of reassortments from Norwegian ancestors.


Asunto(s)
Biología Computacional , Brotes de Enfermedades , Enfermedades de los Peces/epidemiología , Enfermedades de los Peces/mortalidad , Genoma Viral , Isavirus/genética , Infecciones por Orthomyxoviridae/veterinaria , Salmón/virología , Secuencia de Aminoácidos , Animales , Chile/epidemiología , Enfermedades de los Peces/virología , Isavirus/química , Isavirus/clasificación , Isavirus/aislamiento & purificación , Conformación Molecular , Datos de Secuencia Molecular , Infecciones por Orthomyxoviridae/epidemiología , Infecciones por Orthomyxoviridae/mortalidad , Infecciones por Orthomyxoviridae/virología , Filogenia , Virus Reordenados/química , Virus Reordenados/clasificación , Virus Reordenados/genética , Virus Reordenados/aislamiento & purificación , Alineación de Secuencia , Proteínas Virales/química , Proteínas Virales/genética
14.
Placenta ; 31(8): 731-7, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20580083

RESUMEN

OBJECTIVES: To determine if fetal-placental hypoxia is a primary outcome of defective spiral artery remodeling. STUDY DESIGN: Pregnancies in Rag2(-/-)Il2rg(-/-) double knock-out mice, which fail to undergo normal physiological spiral arterial remodeling, were compared to syngeneic BALB/c control pregnancies. Mice at gestation day (gd)6, 8, 10, 12 and 18 were infused with Hypoxyprobe-1 before euthanasia to enable detection of cellular hypoxia by immunohistochemistry. RESULTS: In implantation sites of both phenotypes, trophoblast cells were reactive to Hypoxyprobe-1. No major differences were observed between the phenotypes in decidua or placenta at any gd or in gd18 fetal brain, lung, heart, liver or intestine or in maternal heart, brain, liver or spleen. Maternal kidneys from BALB/c were significantly hypoxic to Rag2(-/-)Il2rg(-/-) kidneys. CONCLUSIONS: In mice, lack of pregnancy-associated spiral artery remodeling does not impair oxygen delivery to the conceptus, challenging the concept that deficient spiral arterial remodeling leads to fetal hypoxia in human gestational complications such as preeclampsia and fetal growth restriction. The isolated hypoxic response of normal kidney has revealed that renal lymphocytes may have unique, tissue-specific regulatory actions on vasoconstriction that are pregnancy independent.


Asunto(s)
Implantación del Embrión , Enfermedades Fetales/metabolismo , Hipoxia/metabolismo , Oxígeno/metabolismo , Placenta/metabolismo , Arteria Uterina/fisiología , Animales , Femenino , Túbulos Renales/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Embarazo
15.
Clin EEG Neurosci ; 41(1): 24-31, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20307013

RESUMEN

Brain activity underlying explicit and implicit processing of face familiarity was assessed by Event-Related Potentials (ERPs) elicited by famous and unknown faces with happy or neutral expressions. A set of faces was presented in a familiarity judgment (explicit) task and another in an expression judgment (implicit familiarity) task. After recording, these tasks were repeated exchanging the stimuli, and post-recording behavioral data from the familiarity task were used for re-averaging EEG segments from the expression task. Both explicit and implicit processing of famous faces resulted in an enhanced N250. Explicit processing of famous faces was specifically associated with earlier N400 and P600, with increased activity within brain areas involved in identity processing around 250 and 450 ms. These findings suggest different brain dynamics for explicit and implicit face processing, and that implicit processing of the identity in the context of an expression task is mainly associated with the transient activation of face representations in memory.


Asunto(s)
Corteza Cerebral/fisiología , Potenciales Evocados Visuales/fisiología , Cara , Memoria/fisiología , Reconocimiento Visual de Modelos/fisiología , Adulto , Electroencefalografía , Femenino , Humanos , Masculino , Estimulación Luminosa , Adulto Joven
16.
Placenta ; 31(4): 327-33, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20149452

RESUMEN

OBJECTIVE: Wingless-type mouse mammary tumor virus integration site family, member 5A (WNT5A), is expressed in mouse decidua and is thought to play an important role in decidualization. We examined expression of the receptor for WNT5A, receptor tyrosine kinase-like orphan receptor 2 (ROR2), in the uteri of cycling and pregnant mice. STUDY DESIGN: Reverse transcription (RT)-PCR and immunohistochemistry were performed. RESULTS: RT-PCR revealed that transcripts for Ror2, Wnt3a, Wnt5a and inhibitor of WNT signaling, Dickkopf homolog 1 (Dkk1), were present in the pregnant uterus. Immunohistochemistry revealed that in the virgin uterus, ROR2 is expressed in stromal cells and on the basal side of uterine gland and endometrial epithelial cells. During pregnancy, both the luminal and basal side of uterine gland epithelial cells expressed ROR2, stromal cell expression of ROR2 became more frequent and ROR2 expressing uterine Natural Killer (NK) cells and cells lining the maternal vascular space emerged. Immunofluorescence imaging and flow cytometry revealed that although uterine NK cells expressed ROR2, NK cells of the spleen were ROR2 negative. CONCLUSION: The expression of ROR2 by endometrial epithelial cells may suggest WNT signaling has roles in uterine epithelial cell polarity or implantation. Expression of ROR2 by uterine NK cells may suggest WNT signaling regulates uterine NK cell functions such angiogenesis and regulation of trophoblast migration. In summary, our results show that ROR2 expression by maternal uterine cells is influenced by pregnancy.


Asunto(s)
Receptores Huérfanos Similares al Receptor Tirosina Quinasa/biosíntesis , Útero/metabolismo , Animales , Femenino , Péptidos y Proteínas de Señalización Intercelular/genética , Células Asesinas Naturales/metabolismo , Ratones , Embarazo , Receptores Huérfanos Similares al Receptor Tirosina Quinasa/genética , Proteínas Wnt/genética , Proteína Wnt-5a , Proteína Wnt3 , Proteína Wnt3A
17.
Placenta ; 30(8): 677-85, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19560201

RESUMEN

Human decidual stromal cells (DSC) have been shown to be involved in different immune functions that may be relevant for the relationship between the mother and fetus and hence for successful pregnancy. The expression of death ligands by fetal trophoblast and maternal decidual cells has been proposed as a mechanism for the establishment of materno-fetal immunotolerance. This study intended to elucidate the interrelations between DSC and lymphocytes. We analyzed the expression and function of death receptors and ligands in DSC maintained in culture. These DSC lines expressed CD95 and TNF-related apoptosis-inducing ligand receptor-2 (TRAIL-R2), although they were resistant to death receptor-mediated apoptosis. Regarding the expression of CD95L and TRAIL, it was variable among DSC lines although none of them induced apoptosis in death ligand-sensitive Jurkat T cells. Interestingly, most of the DSC lines, as well as fresh DSC, reduced apoptosis in Jurkat cells induced by anti-CD95 antibody and recombinant TRAIL. The protective effect of DSC was observed when they were co-cultured with Jurkat cells in Transwell plates, indicating that DSC may produce soluble factors of importance for lymphocyte survival. Moreover, the viability of peripheral blood lymphocytes and decidual lymphocytes was improved when co-cultured with DSC. Our results suggest that DSC, far from inducing apoptosis, may be relevant in the regulation of lymphocyte survival at the materno-fetal interface.


Asunto(s)
Apoptosis/inmunología , Decidua/citología , Decidua/inmunología , Linfocitos/citología , Linfocitos/inmunología , Intercambio Materno-Fetal/inmunología , Células del Estroma/citología , Células del Estroma/inmunología , Apoptosis/efectos de los fármacos , Línea Celular , Supervivencia Celular/inmunología , Técnicas de Cocultivo , Doxorrubicina/farmacología , Proteína Ligando Fas/metabolismo , Femenino , Humanos , Tolerancia Inmunológica , Células Jurkat , Linfocitos/efectos de los fármacos , Embarazo , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Ácido Valproico/farmacología
18.
Clin Exp Pharmacol Physiol ; 36(8): 803-9, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19215232

RESUMEN

1. Recently, we demonstrated that oral captopril treatment improved diastolic function and attenuated cardiac remodelling after myocardial infarction (MI) in rats. Considering the feasible role of the brain renin-angiotensin system (RAS) in heart failure, in the present study we investigated the role of the captopril injected intracerebroventricularly (i.c.v.) on the progression of cardiac dysfunction. 2. Male Wistar rats underwent experimental MI or sham operation. Infarcted animals received daily i.c.v. injections of captopril (approximately 200 mg/kg; MI + Cap) or saline (MI) from 11 to 18 days after infarction. Electro- and echocardiogram assessments were performed before and after i.c.v. treatment (10 and 18 days after MI, respectively). Water and hypertonic saline ingestion were determined daily between 12 and 16 days after MI. 3. Electrocardiograms from the MI and MI + Cap groups showed signs that resembled large MI before and after i.c.v. treatment. However, despite similar systolic dysfunction observed in both groups, only captopril-treated rats exhibited reduced left ventricular (LV) dilatation and improved LV filling, as assessed by echocardiograms, and low levels of water ingestion compared with the saline-treated control group. 4. The results of the present study suggest that the brain RAS may participate in the development of cardiac dysfunction induced by ischaemia and that inhibition of the brain RAS may provide a new strategy for the prevention of diastolic dysfunction.


Asunto(s)
Encéfalo/metabolismo , Diástole/efectos de los fármacos , Infarto del Miocardio/metabolismo , Sistema Renina-Angiotensina/efectos de los fármacos , Inhibidores de la Enzima Convertidora de Angiotensina/administración & dosificación , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Animales , Encéfalo/efectos de los fármacos , Captopril/administración & dosificación , Captopril/farmacología , Captopril/uso terapéutico , Modelos Animales de Enfermedad , Ecocardiografía , Electrocardiografía , Inyecciones Intraventriculares , Masculino , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/fisiopatología , Ratas , Ratas Wistar
19.
Ter. psicol ; 26(2): 215-228, dic. 2008. tab, graf
Artículo en Español | LILACS | ID: lil-545971

RESUMEN

Se presentan los resultados de la aplicación de un cuestionario diseñado para conocer la opinión de psicólogos/as chilenos/as acerca del Código de Ética del Colegio de Psicólogos de Chile (A.G.) y su propensión a adscribir a sus normas. La muestra fue obtenida mediante un muestreo no probabilístico, por disposición de autoselección, compuesta por 170 psicólogos/as, titulados/as en más de 20 universidades distintas, principalmente sujetos jóvenes y que se desempeñan en una amplia gama de ámbitos profesionales. Los resultados muestran que los profesionales que ejercen en el ámbito clínico y afiliados al Colegio de Psicólogos, presentarían una mayor propensión a adscribir a la norma, en comparación con quienes trabajan en otros campos profesionales. Se concluye que tanto el contexto de la post modernidad como la diversificación de roles profesionales obliga a repensar la dimensión ética presente en el ejercicio de la profesión en la actualidad.


The results of the application of a questionnaire design to access to the opinión of Chilean Psychologists about the Code of Ethics Code and their propensity to abide by it are presented. The sampling was obtained through a non random survey, by self selection, and was integrated by 170 psychologists graduated in more than 20 different universities, preferably young adults that work in a wide variety of professional fields. The results show that the professionals that work as clinical psychologists and are members of the Chilean Psychologist's Association, tend to more strongly abide by the norms of the association, in comparison with those that work in other ßreas of the profession. The conclusión is that both the postmodern context as well as the diversification of professional roles obligates to rethink the ethic dimensión in the exercise of the profession at the present time.


Asunto(s)
Humanos , Masculino , Adulto , Femenino , Persona de Mediana Edad , Consejos de Especialidades , Códigos de Ética , Psicología/ética , Psicología , Ética Profesional , Chile , Encuestas y Cuestionarios , Práctica Profesional/ética
20.
Braz. j. biol ; 67(4): 771-776, Nov. 2007. graf
Artículo en Inglés | LILACS | ID: lil-474205

RESUMEN

The purpose of this study was to explore the role of L-5-hydroxytryptophan (L-HTP) and its relationship with the renin-angiotensin system (RAS) on the drinking behavior in Japanese quails. Normally-hydrated quails that received injections of L-HTP (12.5; 25 and 50 mg.kg-1) by the intracoelomic route (ic) expressed an increase in water intake, which was inhibited by captopril, an angiotensin converting enzyme (ACE) inhibitor. In addition, captopril also induced such a response in birds under previous fluid deprivation. High doses of captopril (35-70 mg.kg-1, sc) in normally-hydrated quails decreased the spontaneous water intake while low doses of captopril (2-5 mg.kg-1, sc) did not prompt water intake after L-HTP administration. Losartan, an AT1 receptor antagonist in mammals, did not change the water intake levels in normally-hydrated or water-deprivated birds. Serotonin (5-HT) injections did not provoke its known dipsogenic response.


O objetivo deste estudo foi investigar a influência do L-5-hidroxitriptofano (L-HTP) e sua relação com o sistema renina-angiotensina (SRA) no comportamento dipsogênico de codornas. Codornas normohidratadas que receberam L-HTP em diferentes doses (12,5; 25 e 50 mg.kg-1) por via intracelomática (ic) expressaram um aumento na ingestão de água, o qual foi suprimido pela administração prévia de captopril (inibidor da ECA-enzima conversora de angiotensina). Esta ação inibitória do captopril, em menor intensidade, foi também evidenciada em aves previamente submetidas ao jejum hídrico. O tratamento isolado com captopril (35-70 mg.kg-1) reduziu consideravelmente a ingestão espontânea de água em codornas normohidratadas, enquanto baixas doses (2-5 mg.kg-1) não provocaram aumento na ingestão de água induzida pelo L-HTP. Losartan, um antagonista de receptores AT1 em mamíferos, não foi capaz de modificar os níveis de ingestão hídrica, tanto em aves normohidratadas quanto em aves privadas de água. Serotonina aplicada perifericamente não promoveu a conhecida resposta dipsogênica de mamíferos.


Asunto(s)
Animales , Masculino , /farmacología , Coturnix/fisiología , Conducta de Ingestión de Líquido/efectos de los fármacos , Sistema Renina-Angiotensina/efectos de los fármacos , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Captopril/farmacología , Conducta de Ingestión de Líquido/fisiología , Sistema Renina-Angiotensina/fisiología , Factores de Tiempo
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