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1.
Plant Cell Physiol ; 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38668644

RESUMEN

Since the discovery of brassinolide in the pollen of rapeseed, brassinosteroids (BRs) have consistently been associated with reproductive traits. However, compared to what is known for how BRs shape vegetative development, the understanding of how these hormones regulate reproductive traits is comparatively still lacking. Nevertheless, there is now considerable evidence that BRs regulate almost all aspects of reproduction, from ovule and pollen formation to seed and fruit development. Here, we review the current body of knowledge on how BRs regulate reproductive processes in plants, and what is known about how these pathways are transduced at the molecular level. We then discuss how the manipulation of BR biosynthesis and signaling can be a promising avenue for improving crop traits which rely on efficient reproduction. We thus propose that BR hold an untapped potential for plant breeding, which could contribute to attain food security in the coming years.

2.
J Neurosci Res ; 102(5): e25355, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38808645

RESUMEN

Gamma aminobutyric acid (GABA) is a critical inhibitory neurotransmitter in the central nervous system that plays a vital role in modulating neuronal excitability. Dysregulation of GABAergic signaling, particularly involving the cotransporters NKCC1 and KCC2, has been implicated in various pathologies, including epilepsy, schizophrenia, autism spectrum disorder, Down syndrome, and ischemia. NKCC1 facilitates chloride influx, whereas KCC2 mediates chloride efflux via potassium gradient. Altered expression and function of these cotransporters have been associated with excitotoxicity, inflammation, and cellular death in ischemic events characterized by reduced cerebral blood flow, leading to compromised tissue metabolism and subsequent cell death. NKCC1 inhibition has emerged as a potential therapeutic approach to attenuate intracellular chloride accumulation and mitigate neuronal damage during ischemic events. Similarly, targeting KCC2, which regulates chloride efflux, holds promise for improving outcomes and reducing neuronal damage under ischemic conditions. This review emphasizes the critical roles of GABA, NKCC1, and KCC2 in ischemic pathologies and their potential as therapeutic targets. Inhibiting or modulating the activity of these cotransporters represents a promising strategy for reducing neuronal damage, preventing excitotoxicity, and improving neurological outcomes following ischemic events. Furthermore, exploring the interactions between natural compounds and NKCC1/KCC2 provides additional avenues for potential therapeutic interventions for ischemic injury.


Asunto(s)
Isquemia Encefálica , Muerte Celular , Cotransportadores de K Cl , Miembro 2 de la Familia de Transportadores de Soluto 12 , Simportadores , Ácido gamma-Aminobutírico , Animales , Humanos , Ácido gamma-Aminobutírico/metabolismo , Simportadores/metabolismo , Miembro 2 de la Familia de Transportadores de Soluto 12/metabolismo , Muerte Celular/fisiología , Muerte Celular/efectos de los fármacos , Isquemia Encefálica/metabolismo , Isquemia Encefálica/tratamiento farmacológico
3.
Eur Ann Allergy Clin Immunol ; 55(4): 180-188, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-35261226

RESUMEN

Summary: Background. Patients and Public Involvement in every stage of the patient-centered health research cycle is the key to the development of innovative solutions with an impact on patients' care. Methods. This protocol describes the development of ConectAR, a network to promote the involvement of patients with asthma and their carers in the health research cycle. Results. This protocol comprehends 4 tasks: 1) define the mission, vision, governance and activities of the network through focus groups; 2) establish the communication strategy and tools; 3) test the feasibility of the network in a Delphi study on the research priorities for asthma in Portugal; 4) coordination and dissemination activities. Conclusions. This network will improve research by ensuring that patients and carers have an active role in the co-creation of impactful solutions for asthma.


Asunto(s)
Asma , Cuidadores , Humanos , Grupos Focales , Portugal
4.
Cell Mol Neurobiol ; 42(6): 1693-1725, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33730305

RESUMEN

Ischemia is characterized by a transient, insufficient, or permanent interruption of blood flow to a tissue, which leads to an inadequate glucose and oxygen supply. The nervous tissue is highly active, and it closely depends on glucose and oxygen to satisfy its metabolic demand. Therefore, ischemic conditions promote cell death and lead to a secondary wave of cell damage that progressively spreads to the neighborhood areas, called penumbra. Brain ischemia is one of the main causes of deaths and summed with retinal ischemia comprises one of the principal reasons of disability. Although several studies have been performed to investigate the mechanisms of damage to find protective/preventive interventions, an effective treatment does not exist yet. Adenosine is a well-described neuromodulator in the central nervous system (CNS), and acts through four subtypes of G-protein-coupled receptors. Adenosine receptors, especially A1 and A2A receptors, are the main targets of caffeine in daily consumption doses. Accordingly, caffeine has been greatly studied in the context of CNS pathologies. In fact, adenosine system, as well as caffeine, is involved in neuroprotection effects in different pathological situations. Therefore, the present review focuses on the role of adenosine/caffeine in CNS, brain and retina, ischemic events.


Asunto(s)
Cafeína , Isquemia , Fármacos Neuroprotectores , Adenosina/metabolismo , Encéfalo , Cafeína/farmacología , Sistema Nervioso Central , Glucosa/metabolismo , Humanos , Fármacos Neuroprotectores/farmacología , Oxígeno/metabolismo , Receptores Purinérgicos P1 , Retina
5.
Environ Res ; 199: 111282, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34015296

RESUMEN

BACKGROUND: Residential exposure to pesticides may occur via inhalation of airborne pesticides, direct skin contacts with pesticide-contaminated surfaces, and consumption of food containing pesticide residues. The aim was to study the association of dermal exposure to pesticides between the use and non-use periods, between farmer and non-farmer families and between dermal exposure and the excretion of metabolites from urine in residents living close to treated agricultural fields. METHODS: In total, 112 hand wipes and 206 spot urine samples were collected from 16 farmer and 38 non-farmer participants living within 50 m from an agricultural field in the Netherlands. The study took place from May 2016 to December 2017 during the use as well as the non-use periods of pesticides. Hand wipes were analysed for the parent compound and urines samples for the corresponding urinary metabolite of five applied pesticides: asulam, carbendazim (applied as thiophanate-methyl), chlorpropham, prochloraz and tebuconazole. Questionnaire data was used to study potential determinants of occurrence and levels of pesticides in hand wipes according to univariate and multivariate analysis. RESULTS: Carbendazim and tebuconazole concentrations in hand wipes were statistically significantly higher in the pesticide-use period compared to the non-use period. In addition, especially during the use periods, concentrations were statistically significantly higher in farmer families compared to non-farmer families. For asulam, chlorpropham and prochloraz, the frequency of non-detects was too high (57-85%) to be included in this analysis. The carbendazim contents in urine samples and hand wipes were correlated on the first and second day after taking the hand wipe, whereas chlorpropham was only observed to be related on the second day following the spray event. CONCLUSIONS: Concentrations in hand wipes were overall higher in pesticide use periods compared to non-use periods and higher in farmer families compared to non-farmer families. Only for carbendazim a strong correlation between concentrations in hand wipes and its main metabolite in urine was observed, indicating dermal exposure via contaminated indoor surfaces. We expect this to be related to the lower vapour pressure and longer environmental lifetime of carbendazim compared to the other pesticides studies.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Biomarcadores , Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente , Mano , Humanos , Países Bajos , Plaguicidas/análisis
6.
Purinergic Signal ; 16(1): 41-59, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32078115

RESUMEN

In infants, the main cause of blindness is retinopathy of prematurity that stems in a hypoxic-ischemic condition. Caffeine is a psychoactive compound that at low to moderate concentrations, selectively inhibits adenosine A1 and A2A receptors. Caffeine exerts beneficial effects in central nervous system of adult animal models and humans, whereas it seems to have malefic effect on the developing tissue. We observed that 48-h exposure (during synaptogenesis) to a moderate dose of caffeine (30 mg/kg of egg) activated pro-survival signaling pathways, including ERK, CREB, and Akt phosphorylation, alongside BDNF production, and reduced retinal cell death promoted by oxygen glucose deprivation in the chick retina. Blockade of TrkB receptors and inhibition of CREB prevented caffeine protection effect. Similar signaling pathways were described in previously reported data concerning chemical preconditioning mechanism triggered by NMDA receptors activation, with low concentrations of agonist. In agreement to these data, caffeine increased NMDA receptor activity. Caffeine decreased the levels of the chloride co-transporter KCC2 and delayed the developmental shift on GABAA receptor response from depolarizing to hyperpolarizing. These results suggest that the caffeine-induced delaying in depolarizing effect of GABA could be facilitating NMDA receptor activity. DPCPX, an A1 adenosine receptor antagonist, but not A2A receptor inhibitor, mimicked the effect of caffeine, suggesting that the effect of caffeine occurs through A1 receptor blockade. In summary, an in vivo caffeine exposure could increase the resistance of the retina to ischemia-induced cell death, by triggering survival pathways involving CREB phosphorylation and BDNF production/TrkB activation.


Asunto(s)
Cafeína/farmacología , Muerte Celular/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Retina/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Animales , Hipoxia de la Célula/efectos de los fármacos , Embrión de Pollo , Pollos , Isquemia/metabolismo
7.
Transpl Infect Dis ; 16(1): 135-40, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24383613

RESUMEN

Trichosporon species are rare etiologic agents of invasive fungal infection in solid organ transplant (SOT) recipients. We report 2 well-documented cases of Trichosporon inkin invasive infection in SOT patients. We also conducted a detailed literature review of Trichosporon species infections in this susceptible population. We gathered a total of 13 cases of Trichosporon species infections. Any type of organ transplantation can be complicated by Trichosporon infection. Bloodstream infections and disseminated infections were the most common clinical presentations. Liver recipients with bloodstream or disseminated infections had poor prognoses. Although the most common species was formerly called Trichosporon beigelii, this species name should no longer be used because of the changes in the taxonomy of this genus resulting from the advent of molecular approaches, which were also used to identify the strains isolated from our patients. Antifungal susceptibility testing highlights the possibility of multidrug resistance. Indeed, Trichosporon has to be considered in cases of breakthrough infection or treatment failure under echinocandins or amphotericin therapy. Voriconazole seems to be the best treatment option.


Asunto(s)
ADN de Hongos/análisis , Empiema/inmunología , Rechazo de Injerto/prevención & control , Trasplante de Corazón , Huésped Inmunocomprometido , Inmunosupresores/uso terapéutico , Enfermedades Pulmonares Fúngicas/inmunología , Trasplante de Pulmón , Mediastinitis/inmunología , Pericarditis/inmunología , Trichosporon/genética , Tricosporonosis/inmunología , Adulto , Antifúngicos/uso terapéutico , ADN Intergénico/análisis , ADN Ribosómico/análisis , Farmacorresistencia Fúngica , Empiema/diagnóstico , Empiema/tratamiento farmacológico , Humanos , Enfermedades Pulmonares Fúngicas/diagnóstico , Enfermedades Pulmonares Fúngicas/tratamiento farmacológico , Masculino , Mediastinitis/diagnóstico , Mediastinitis/tratamiento farmacológico , Pruebas de Sensibilidad Microbiana , Pericarditis/diagnóstico , Pericarditis/tratamiento farmacológico , Derrame Pleural/diagnóstico , Derrame Pleural/tratamiento farmacológico , Derrame Pleural/inmunología , Pirimidinas/uso terapéutico , Análisis de Secuencia de ADN , Triazoles/uso terapéutico , Tricosporonosis/diagnóstico , Tricosporonosis/tratamiento farmacológico , Voriconazol , Adulto Joven
8.
Sci Total Environ ; 927: 171999, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38554951

RESUMEN

This article aims to critically review the current state of knowledge on in vitro toxicological assessments of particulate emissions from residential biomass heating systems. The review covers various aspects of particulate matter (PM) toxicity, including oxidative stress, inflammation, genotoxicity, and cytotoxicity, all of which have important implications for understanding the development of diseases. Studies in this field have highlighted the different mechanisms that biomass combustion particles activate, which vary depending on the combustion appliances and fuels. In general, particles from conventional combustion appliances are more potent in inducing cytotoxicity, DNA damage, inflammatory responses, and oxidative stress than those from modern appliances. The sensitivity of different cell lines to the toxic effects of biomass combustion particles is also influenced by cell type and culture conditions. One of the main challenges in this field is the considerable variation in sampling strategies, sample processing, experimental conditions, assays, and extraction techniques used in biomass burning PM studies. Advanced culture systems, such as co-cultures and air-liquid interface exposures, can provide more accurate insights into the effects of biomass combustion particles compared to simpler submerged monocultures. This review provides critical insights into the complex field of toxicity from residential biomass combustion emissions, underscoring the importance of continued research and standardisation of methodologies to better understand the associated health hazards and to inform targeted interventions.


Asunto(s)
Contaminantes Atmosféricos , Biomasa , Material Particulado , Material Particulado/toxicidad , Contaminantes Atmosféricos/toxicidad , Calefacción , Humanos , Estrés Oxidativo
9.
J Control Release ; 368: 184-198, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38395155

RESUMEN

Streptococcus pneumoniae is an important human pathogen. Currently used conjugate vaccines are effective against invasive disease, but protection is restricted to serotypes included in the formulation, leading to serotype replacement. Furthermore, protection against non-invasive disease is reported to be considerably lower. The development of a serotype-independent vaccine is thus important and Pneumococcal surface protein A (PspA) is a promising vaccine candidate. PspA shows some diversity and can be classified in 6 clades and 3 families, with families 1 and 2 being the most frequent in clinical isolates. The ideal vaccine should thus induce protection against the two most common families of PspA. The aim of this work was to develop a liposome-based vaccine containing PspAs from family 1 and 2 and to characterize its immune response. Liposomes (LP) composed of dipalmitoylphosphatidylcholine (DPPC) and 3ß-[N-(N',N'-dimethylaminoethane)-carbamoyl]cholesterol (DC-Chol) with or without α-galactosylceramide (α-GalCer) were produced by microfluidics, encapsulating PspA from clade 1 (PspA1, family 1) and/or clade 4 (PspA4Pro, family 2) followed by spray-drying with trehalose to form nanocomposite microparticles carriers (NCMP). LP/NCMPs showed good stability and preservation of protein activity. LP/NCMPs containing PspA1 and/or PspA4Pro were used for immunization of mice targeting the lungs. High serum IgG antibody titers against both PspA1 and PspA4Pro were detected in animals immunized with LP/NCMPs containing α-GalCer, with a balance of IgG1 and IgG2a titers. IgG in sera from immunized mice bound to pneumococcal strains from different serotypes and expressing different PspA clades, indicating broad recognition. Mucosal IgG and IgA were also detected. Importantly, immunization with LP/NCMPs induced full protection against strains expressing PspAs from family 1 and 2. Furthermore, CD4+ resident memory T cells were detected in the lungs of the immunized animals that survived the challenge.


Asunto(s)
Galactosilceramidas , Infecciones Neumocócicas , Streptococcus pneumoniae , Humanos , Animales , Ratones , Liposomas , Polvos , Infecciones Neumocócicas/prevención & control , Proteínas Bacterianas , Inmunización , Vacunas Neumococicas , Inmunoglobulina G , Pulmón , Anticuerpos Antibacterianos , Ratones Endogámicos BALB C
10.
Infect Dis Now ; 51(3): 260-265, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33144264

RESUMEN

OBJECTIVE: Identify risk factors for microcephaly and evaluate historical trends of microcephaly and arboviruses to recognize patterns and anomalies that indicate the beginning of the microcephaly epidemic associated with Zika infection. METHODS: The head circumferences of 62,298 newborns was analyzed to identify cases of microcephaly between 2014 and 2017. We compared the groups of newborns with normal head circumferences and those with microcephaly to identify risk factors. A time series with the incidences of microcephaly was analyzed to assess the appearance of anomalous values in order to identify the beginning of the microcephaly epidemic. Data on the incidence of dengue fever was used to develop a control chart, aiming to identify changes in incidence and seasonality that could suggest the circulation of a new arbovirus. FINDINGS: Premature newborns, children of mothers under 20 years of age and those born in 2014 and 2015 had a higher risk of microcephaly. Three quarters with anomalous incidences of microcephaly were identified, the first in 2014 and the others in 2015. The dengue fever epidemic curve in 2013 shows persistence of high incidences in atypical periods, suggesting the entry of a new virus in the 3rd and 4th quarters. CONCLUSIONS: These findings represent epidemiological evidence of the existence of cases of Zika virus between the 2nd quarter of 2013 and the beginning of 2014. The results add new elements to understanding the Zika virus epidemic in the Americas.


Asunto(s)
Epidemias , Microcefalia/epidemiología , Complicaciones Infecciosas del Embarazo/epidemiología , Infección por el Virus Zika/epidemiología , Adulto , Américas/epidemiología , Arbovirus/aislamiento & purificación , Brasil/epidemiología , Estudios Transversales , Dengue/epidemiología , Femenino , Humanos , Incidencia , Recién Nacido , Masculino , Microcefalia/virología , Embarazo , Complicaciones Infecciosas del Embarazo/virología , Factores de Riesgo , Adulto Joven , Virus Zika/aislamiento & purificación , Infección por el Virus Zika/virología
11.
J Oral Biol Craniofac Res ; 10(4): 738-742, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33101892

RESUMEN

PURPOSE: Rapid maxillary expansion (RME) is the most frequent orthopedic procedure in cleft subjects. However, little is known about its effects on the mandible. The aim of this study was to investigate the spontaneous response of the mandibular teeth following RME. METHODS: This prospective cohort study was carried out with a sample of thirty participants with unilateral cleft lip and palate (UCLP), 8-15 years old, who had transverse maxillary deficiency. Two participants were excluded. They were allocated into three groups: G1 (n = 10), G2 (n = 10), and G3 (n = 8). G1 was treated with a Fan-type expander; G2 with an iMini expander; and G3 with a Hyrax expander. Measurements were performed in Cone Beam CT scans obtained before treatment (T1) and 3 months post-expansion (T2). The primary outcomes were buccolingual inclination of mandibular first molars and canines, and intercanine and intermolar width at different levels. RESULTS: Dental changes were significant (P < 0.05) for intercanine width, increasing in G1 and G2, and for intermolar width, increasing in G2 and G3. There were no significant differences among groups (P > 0.05). CONCLUSION: RME in UCLP subjects performed with these expanders may lead to significant spontaneous changes in both anterior and posterior region of the mandible.

12.
Environ Toxicol ; 24(3): 259-70, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18655178

RESUMEN

The impact of diffuse pollution in aquatic systems is of great concern due to the difficult to measure and regulate it. As part of an ecological risk assessment (ERA), this study aims to use a whole sample toxicity assessment to evaluate the toxicity of water and sediment from Lake Vela, a lake that has been exposed to diffuse pollution. In this way, standard (algae: Pseudokirchneriella subcapitata; cladoceran: Daphnia magna) and local species (algae: Aphanizomenon flos-aquae; cladoceran: Daphnia longispina) were exposed to surface water, and sediment elutriates were collected seasonally from two sites at Lake Vela: one near the east bank (ES), surrounded by agricultural lands; and the other near the west bank (WS), surrounded by a forest. The results confirmed the seasonal contamination of both environmental compartments by pesticides, including organochlorine pesticides, and the presence of high concentrations of nutrients. Although both sites were contaminated, higher levels of pesticides and nutrients were detected in ES, particularly in the sediments. Bioassays showed that water samples (100% concentration) collected in summer and autumn significantly affected the growth rate of P. subcapitata, which could be attributed to the presence of pesticides. Likewise, they revealed an apparent toxicity of elutriates for P. subcapitata and for both daphnids, in summer and autumn. In fact, although pesticides were not detected in elutriates, high levels of un-ionized ammonia were recorded, which is considered highly toxic to aquatic life. By comparing the several species, P. subcapitata was revealed to be the most sensitive one, followed by the daphnids, and then by A. flos-aquae. Results obtained in this study underlined the importance of whole samples toxicity assessment for characterizing the ecological effects of complex mixtures from diffuse inputs, in the ERA processes.


Asunto(s)
Agua Dulce/análisis , Sedimentos Geológicos/análisis , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad , Acetamidas/análisis , Acetamidas/toxicidad , Aldrín/análisis , Aldrín/toxicidad , Animales , Bioensayo , Daphnia/efectos de los fármacos , Daphnia/crecimiento & desarrollo , Dieldrín/análisis , Dieldrín/toxicidad , Monitoreo del Ambiente , Eucariontes/efectos de los fármacos , Eucariontes/crecimiento & desarrollo , Sedimentos Geológicos/clasificación , Glicina/análogos & derivados , Glicina/análisis , Glicina/toxicidad , Nitrógeno/análisis , Nitrógeno/toxicidad , Plaguicidas/análisis , Plaguicidas/toxicidad , Fósforo/análisis , Fósforo/toxicidad , Portugal , Medición de Riesgo , Estaciones del Año , Pruebas de Toxicidad , Glifosato
13.
Histopathology ; 53(6): 715-27, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19076685

RESUMEN

AIMS: Annexin A1 (ANXA1) is a soluble cytoplasmic protein, moving to membranes when calcium levels are elevated. ANXA1 has also been shown to move to the nucleus or outside the cells, depending on tyrosine-kinase signalling, thus interfering in cytoskeletal organization and cell differentiation, mostly in inflammatory and neoplastic processes. The aim was to investigate subcellular patterns of immunohistochemical expression of ANXA1 in neoplastic and non-neoplastic samples from patients with laryngeal squamous cell carcinomas (LSCC), to elucidate the role of ANXA1 in laryngeal carcinogenesis. METHODS AND RESULTS: Serial analysis of gene expression experiments detected reduced expression of ANXA1 gene in LSCC compared with the corresponding non-neoplastic margins. Quantitative polymerase chain reaction confirmed ANXA1 low expression in 15 LSCC and eight matched normal samples. Thus, we investigated subcellular patterns of immunohistochemical expression of ANXA1 in 241 paraffin-embedded samples from 95 patients with LSCC. The results showed ANXA1 down-regulation in dysplastic, tumourous and metastatic lesions and provided evidence for the progressive migration of ANXA1 from the nucleus towards the membrane during laryngeal tumorigenesis. CONCLUSIONS: ANXA1 dysregulation was observed early in laryngeal carcinogenesis, in intra-epithelial neoplasms; it was not found related to prognostic parameters, such as nodal metastases.


Asunto(s)
Anexina A1/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias Laríngeas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Anexina A1/análisis , Anexina A1/genética , Western Blotting , Carcinoma de Células Escamosas/patología , Femenino , Expresión Génica , Humanos , Inmunohistoquímica , Neoplasias Laríngeas/patología , Masculino , Persona de Mediana Edad
14.
Sci Total Environ ; 374(2-3): 252-9, 2007 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-17316767

RESUMEN

Uranium mining activities in Cunha Baixa, Mangualde (Portugal), were extensive between 1967 and 1993, with high production of poor ore. Ore exploitation left millions of tons of tailings in the surrounding area, close to human houses. Contamination of the area (water and soil compartment) presently represents a serious hazard to humans and wildlife. The aim of this work was to evaluate the acute toxicity of water and sediments from a pond that floods a uranium mine pit, in two periods (spring and autumn). High contents of metals were found in water samples (chiefly Mn, Fe, Al, U, Sr). A battery of assays was applied to screen the acute toxicity of the different compartments using algae, crustaceans and dipterans. Results showed that the sediments were non-toxic, unlike the superficial water. Water toxicity was higher in the autumn, when the effluent was more acidic, compared to spring. In the water toxicity assays, the relative sensitivity of the test species used was Daphnia longispina>Pseudokirchneriella subcapitata>Daphnia magna. The present study is part of the chemical and ecotoxicological characterisation of the aquatic compartment performed in the Tier 1 of the Ecological Risk Assessment of the Cunha Baixa mining area.


Asunto(s)
Metales/toxicidad , Contaminantes Químicos del Agua/toxicidad , Contaminantes Radiactivos del Agua/toxicidad , Animales , Bioensayo , Chironomidae/efectos de los fármacos , Chironomidae/crecimiento & desarrollo , Chironomidae/efectos de la radiación , Chlorophyta/efectos de los fármacos , Chlorophyta/crecimiento & desarrollo , Chlorophyta/efectos de la radiación , Daphnia/efectos de los fármacos , Daphnia/efectos de la radiación , Sedimentos Geológicos , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Larva/efectos de la radiación , Metales/análisis , Minería , Portugal , Contaminantes Químicos del Agua/análisis , Contaminantes Radiactivos del Agua/análisis
15.
Domest Anim Endocrinol ; 33(1): 32-46, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16697137

RESUMEN

This study investigated the effect of non-ventilation of the incubator during the first 10 days of incubation and its combination with dexamethasone administration at day 16 or 18 of incubation on hatching parameters and embryo and post-hatch chick juvenile physiology. A total of 2400 hatching eggs produced by Cobb broiler breeders were used for the study. Blood samples were collected at day 18 of incubation, at internal pipping stage (IP), at the end of hatch (day-old chick) and at 7-day-post-hatch for T(3), T(4) and corticosterone levels determination. From 448 to 506 h of incubation, the eggs were checked individually in the hatcher every 2h for pipping and hatching. The results indicate that non-ventilation during the first 10-day shortened incubation duration up to IP, external pipping (EP) and hatch, had no effect on hatchability and led to higher T(3) levels at IP but lower corticosterone levels at 7-day-post-hatch. The injection of dexamethasone at days 16 and 18 of incubation affected hatching and blood parameters in both the ventilated and non-ventilated embryos differentially and the effect was dependent on the age of the embryo. Dexamethasone increased T(3) levels and T(3)/T(4) ratios but the effect was greater with early non-ventilation of eggs. Dexamethasone decreased hatchability but the effect was greater when injected at day 16 and especially in ventilated embryos. The effects of incubation protocols and dexamethasone treatments during incubation were still apparent in the hatched chicks until 7 days of age. The changes in T(3), T(4) and corticosterone levels observed in response to the early incubation conditions and late dexamethasone treatments in this study suggest that incubator ventilation or non-ventilation may influence the hypothalamic-pituitary-adrenal axis (HPA) regulation of stress levels (in terms of plasma corticosterone levels) and thyroid function in the embryo with impact on incubation duration, hatching events and early post-hatch life of the chick. Our results also suggest that some stages of development are more sensitive to dexamethasone administration as effects can be influenced by early incubation protocols.


Asunto(s)
Embrión de Pollo/crecimiento & desarrollo , Dexametasona/farmacología , Glucocorticoides/farmacología , Ventilación/métodos , Animales , Corticosterona/sangre , Incubadoras/veterinaria , Distribución Aleatoria , Análisis de Regresión , Tiroxina/sangre , Triyodotironina/sangre
16.
Int Immunopharmacol ; 35: 127-136, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27039211

RESUMEN

Passiflora alata Curtis (P. alata) leaves have anti-inflammatory properties; the present study aimed to investigate the anti-diabetogenic properties of P. alata aqueous leaf extract. HPLC analysis identified the phenolic compounds catechin, epicatechin and rutin. The aqueous extract was administered for 30weeks to non-obese diabetic (NOD) mice presenting a decrease of 28.6% in diabetes incidence and the number of inflammatory cells in pancreatic islets, when compared with the control group (water). The P. alata group presented an antioxidant effect and decreased lipid peroxidation in the serum of NOD mice. Increased numbers of insulin-positive cells were also observed in the pancreatic islets of the treated group. The diabetic group exhibited higher levels in the glucose tolerance test and glycemic index, in comparison to the P. alata-treated group and non-diabetic control BALB/c mice. In addition, the P. alata extract reduced the percentage and the proliferation index of NOD mice lymphocytes submitted to in vitro dose/response mitogenic stimulation assays. These results suggest that the aqueous extract of P. alata has anti-inflammatory properties, contributing to the protection of beta cells in pancreatic islets in NOD mice, and presents potential for use a supporting approach to treat type 1 diabetes.


Asunto(s)
Antiinflamatorios/uso terapéutico , Antioxidantes/uso terapéutico , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Células Secretoras de Insulina/efectos de los fármacos , Passiflora/inmunología , Extractos Vegetales/uso terapéutico , Animales , Células Cultivadas , Citoprotección , Femenino , Humanos , Insulina/sangre , Células Secretoras de Insulina/fisiología , Peroxidación de Lípido/efectos de los fármacos , Activación de Linfocitos/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos NOD , Hojas de la Planta
17.
J Mol Neurosci ; 14(3): 155-66, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10984191

RESUMEN

There is evidence that raising cellular levels of Cu2+/Zn2+ superoxide dismutase (SOD1) can protect neurons from oxidative injury. We compared a novel method of elevating neuronal SOD activity using a recombinant hybrid protein composed of the atoxic neuronal binding domain of tetanus toxin (C fragment or TTC) and human SOD1 (hSOD1) with increasing cellular SOD levels through overexpression. Fetal murine cortical neurons or N18-RE-105 cells were incubated with the TTC-hSOD1 hybrid protein and compared to cells constitutively expressing hSOD1 for level of SOD activity, cellular localization of hSOD1, and capacity to survive glucose and pyruvate starvation. Cells incubated with TTC-hSOD1 showed a threefold increase in cellular SOD activity over control cells. This level of increase was comparable to fetal cortical neurons from transgenic mice constitutively expressing hSOD1 and transfected N18-RE-105 cells expressing a green fluorescent protein-hSOD1 fusion protein (GFP-hSOD1). Human SOD1 was distributed diffusely throughout the cytoplasm of the transgenic murine neurons and transfected N18-RE-105 cells. In contrast, cells incubated with TTC-hSOD1 showed hSOD1 localized to the cell surface and intra-cytoplasmic vesicles. The cells expressing hSOD1 showed enhanced survival in glucose- and pyruvate-free medium. Neither cortical neurons nor N18-RE-105 cells incubated in TTC-hSOD1 showed increased survival during starvation. Access to the site where toxic superoxides are generated or their targets may be necessary for the protective function of SOD1.


Asunto(s)
Neuronas/citología , Neuronas/metabolismo , Estrés Oxidativo/fisiología , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Animales , Muerte Celular/fisiología , Supervivencia Celular/fisiología , Corteza Cerebral/citología , Metabolismo Energético/fisiología , Regulación Enzimológica de la Expresión Génica , Genes Reporteros , Proteínas Fluorescentes Verdes , Indicadores y Reactivos/metabolismo , Proteínas Luminiscentes/genética , Ratones , Ratones Endogámicos , Ratones Transgénicos , Neuroblastoma , Fragmentos de Péptidos/genética , Inanición/metabolismo , Superóxido Dismutasa/análisis , Toxina Tetánica/genética , Transfección , Células Tumorales Cultivadas
18.
Neurosurgery ; 8(5): 567-8, 1981 May.
Artículo en Inglés | MEDLINE | ID: mdl-7266796

RESUMEN

The authors present a new technique for tamponade of the nasopharynx after the performance of a transnasophenoidal approach to the hypophysis. This technique consists of placing a Foley balloon catheter in each nasal cavity, extending to the nasopharynx. The position of the balloons and the adequacy of the amount of radiopaque substance used to fill them is determined with x-ray films or a television image intensifier. Among the advantages of the method over tamponade with Vaseline-covered gauze are: (a) better tamponade; (b) the possibility of testing the position and volume of tamponade; (c) the absence of trauma to the nasopharyngeal mucosa upon removal of the catheters after deflation of the balloons; (d) the availability of two airways for respiration in addition to the mouth; and (e) the absence of blood gas alterations and infections.


Asunto(s)
Hipofisectomía/métodos , Humanos
19.
Thyroid ; 6(3): 183-8, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8837324

RESUMEN

The changes in the serum thyroid autoantibodies, antithyroglobulin (TgAb) and antithyroid-peroxidase (TPOAb), lipid profile, and thyroid volume following L-thyroxine (L-T4) therapy is still a controversial matter. We studied 23 patients with goiter due to Hashimoto's thyroiditis; 10 had clinical hypothyroidism (CH) and 13 had subclinical hypothyroidism (SH). Both groups received L-T4 (2.0 to 2.5 micrograms/kg/day) for a median period of 6 months. Serum concentration of TgAb (normal value: < 200 mUI/mL) and TPOAb (normal value: < 150 mUI/mL) were measured by a sensitive IRMA using 125I protein-A. Thyroid volume was determined by ultrasound (normal value: 8-14 mL). At the end of the observation period the median serum TSH concentration decreased significantly in both groups (42.9 to 0.55 in CH and 2.4 to 0.74 mU/L in SH patients) and serum FT4I levels increased only in the CH group (0.87 to 2.1; p < 0.05). Serum TgAb concentration did not change in SH patients (72 to 218 mUI/mL) but declined in CH patients (364.5 to 75 mU/mL; p < 0.05). TPOAb levels also fell in the CH group (871 to 194 mUI/mL; p < 0.05) and no significant change was noted in SH patients (260 to 116 mUI/mL). Further, a significant correlation was obtained between TSH and either TPOAb concentration (rs = 0.569, p < 0.01) or thyroid volume (rs = 0.488, p < 0.05) in the CH group but not in SH patients (rs = 0.232, NS). LDL-cholesterol was higher in the CH (159.4 mg/dL) compared with the SH group (116 mg/dL). Moreover, only in the CH patients was there a significant fall in total cholesterol (224.5 to 165.5 mg/dL, p < 0.05) and in LDL-cholesterol (159.4 to 104.3 mg/dL, p < 0.05) values. The thyroid volume decreased in all patients with CH and in 77% (10/13) of SH patients and a significant median in the thyroid volume decrease was found (39.7% of initial volume in the CH group and 80.9% in SH patients; p < 0.01). The influence of L-T4 on both thyroid autoantibody levels and thyroid volume might be explained by reduction of antigenic substance through a decreased stimulation of thyroid tissue by circulating TSH as was seen in CH but not in SH patients. The benefits of the administration of L-T4 replacement therapy in SH patients due to Hashimoto's thyroiditis remain to be clarified.


Asunto(s)
Autoanticuerpos/sangre , Lípidos/sangre , Glándula Tiroides/inmunología , Glándula Tiroides/patología , Tiroiditis Autoinmune/tratamiento farmacológico , Tiroxina/uso terapéutico , Adolescente , Adulto , Anciano , LDL-Colesterol/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tiroglobulina/inmunología , Glándula Tiroides/diagnóstico por imagen , Tiroiditis Autoinmune/diagnóstico por imagen , Tiroiditis Autoinmune/inmunología , Tirotropina/sangre , Tiroxina/administración & dosificación , Tiroxina/sangre , Ultrasonografía
20.
Rev Inst Med Trop Sao Paulo ; 43(4): 227-30, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11558004

RESUMEN

Reports on children presenting symptoms compatible with the chronic phase of Chagas disease are sporadic. We report a case of a 7-year-old boy who had megaesophagus and megacolon, both of them a consequence of the trypanosomiasis. The etiology was established by means of laboratory and histological features. Based on epidemiological data, the authors concluded that vertical transmission was the most probable route of acquisition. This diagnosis should be considered in children presenting similar complaints, even those living away from endemic areas.


Asunto(s)
Enfermedad de Chagas/diagnóstico , Acalasia del Esófago/diagnóstico , Megacolon/diagnóstico , Enfermedad de Chagas/complicaciones , Enfermedad de Chagas/transmisión , Niño , Acalasia del Esófago/etiología , Humanos , Transmisión Vertical de Enfermedad Infecciosa , Masculino , Megacolon/etiología
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