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1.
Allergy ; 79(4): 908-923, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38311961

RESUMEN

BACKGROUND: Pollen allergy poses a significant health and economic burden in Europe. Disease patterns are relatively homogeneous within Central and Northern European countries. However, no study broadly assessed the features of seasonal allergic rhinitis (SAR) across different Southern European countries with a standardized approach. OBJECTIVE: To describe sensitization profiles and clinical phenotypes of pollen allergic patients in nine Southern European cities with a uniform methodological approach. METHODS: Within the @IT.2020 multicenter observational study, pediatric and adult patients suffering from SAR were recruited in nine urban study centers located in seven countries. Clinical questionnaires, skin prick tests (SPT) and specific IgE (sIgE) tests with a customized multiplex assay (Euroimmun Labordiagnostika, Lübeck, Germany) were performed. RESULTS: Three hundred forty-eight children (mean age 13.1 years, SD: 2.4 years) and 467 adults (mean age 35.7 years SD: 10.0 years) with a predominantly moderate to severe, persistent phenotype of SAR were recruited. Grass pollen major allergenic molecules (Phl p 1 and/or Phl p 5) ranged among the top three sensitizers in all study centers. Sensitization profiles were very heterogeneous, considering that patients in Rome were highly poly-sensitized (sIgE to 3.8 major allergenic molecules per patient), while mono-sensitization was prominent and heterogeneous in other cities, such as Marseille (sIgE to Cup a 1: n = 55/80, 68.8%) and Messina (sIgE to Par j 2: n = 47/82, 57.3%). Co-sensitization to perennial allergens, as well as allergic comorbidities also broadly varied between study centers. CONCLUSIONS: In Southern European countries, pollen allergy is heterogeneous in terms of sensitization profiles and clinical manifestations. Despite the complexity, a unique molecular, multiplex, and customized in-vitro IgE test detected relevant sensitization in all study centers. Nevertheless, this geographical diversity in pollen allergic patients imposes localized clinical guidelines and study protocols for clinical trials of SAR in this climatically complex region.


Asunto(s)
Hipersensibilidad , Rinitis Alérgica Estacional , Adulto , Humanos , Niño , Adolescente , Rinitis Alérgica Estacional/diagnóstico , Rinitis Alérgica Estacional/epidemiología , Inmunoglobulina E , Alérgenos , Polen , Pruebas Cutáneas , Fenotipo
2.
J Chem Inf Model ; 57(1): 1-5, 2017 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-28026944

RESUMEN

The MDANSE software-Molecular Dynamics Analysis of Neutron Scattering Experiments-is presented. It is an interactive application for postprocessing molecular dynamics (MD) simulations. Given the widespread use of MD simulations in material and biomolecular sciences to get a better insight for experimental techniques such as thermal neutron scattering (TNS), the development of MDANSE has focused on providing a user-friendly, interactive, graphical user interface for analyzing many trajectories in the same session and running several analyses simultaneously independently of the interface. This first version of MDANSE already proposes a broad range of analyses, and the application has been designed to facilitate the introduction of new analyses in the framework. All this makes MDANSE a valuable tool for extracting useful information from trajectories resulting from a wide range of MD codes.


Asunto(s)
Simulación de Dinámica Molecular , Difracción de Neutrones , Programas Informáticos , Interfaz Usuario-Computador , Conformación Molecular
3.
Environ Geochem Health ; 39(6): 1273-1289, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28555279

RESUMEN

Mercury (Hg) distribution in saltmarsh sediments and in three selected halophytes (Limonium narbonense, Sarcocornia fruticosa and Atriplex portulacoides) of a wetland system (Marano and Grado Lagoon, Italy) following a contamination gradient in sediments was investigated. The Hg uptake was evaluated at the root system level by calculating the enrichment factor (EF) and in the aboveground tissues by means of the translocation factor (TF). The related methylmercury (MeHg) concentrations in the halophytes were also investigated with regard to the location of the sites and their degree of contamination. Hg concentration in halophytes seemed poorly correlated both with the total Hg in rhizo-sediments and with the specific plant considered, supporting the evidence that the chemico-physical parameters of sediments could significantly affect metal availability for plants. Hg concentrations in roots increased with depth and were 20-fold higher than content measured in related rhizo-sediments (high EF). A low content of Hg is translocated in aboveground tissues (very low TF values), thus highlighting a kind of avoidance strategy of these halophytes against Hg toxicity. MeHg values were comparable between the two sites and among species, but the translocation from below- to aboveground plant tissues was more active.


Asunto(s)
Mercurio/metabolismo , Aguas Salinas/química , Plantas Tolerantes a la Sal/metabolismo , Contaminantes Químicos del Agua/metabolismo , Humedales , Sedimentos Geológicos/química , Italia , Mercurio/toxicidad , Estructuras de las Plantas/química , Estándares de Referencia , Plantas Tolerantes a la Sal/clasificación , Plantas Tolerantes a la Sal/efectos de los fármacos , Especificidad de la Especie , Espectrometría de Fluorescencia , Contaminantes Químicos del Agua/toxicidad
5.
Phys Chem Chem Phys ; 17(17): 11423-31, 2015 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-25853990

RESUMEN

Protein low-frequency vibrational modes are an important portion of a proteins' dynamical repertoire. Yet, it is notoriously difficult to isolate specific vibrational features in the spectra of proteins. Given an appropriately chosen model peptide, and using different experimental conditions, we can simplify the system and gain useful insights into the protein vibrational properties. Combining neutron scattering, depolarized light scattering, and molecular dynamics simulations, we analyse the low frequency vibrations of biological molecules, comparing the results from a small globular protein, lysozyme, and an amphiphilic peptide, NALMA, both in solution and in powder states. Lysozyme and NALMA present similar spectral features in the frequency range between 1 and 10 THz. With the aid of MD simulations, we assign the spectral features to methyl groups' librations (1-5 THz) and hindered torsions (5-10 THz) in NALMA. Our data also show that, while proteins display boson peak vibrations in both powder and solution forms, NALMA exhibits boson peak vibrations in powder form only. This provides insight into the nature of this feature, suggesting a connection of BP collective motions to a characteristic length scale of heterogeneities present in the system. These results provide context for the use of model peptide systems to study protein dynamics; demonstrating both their utility, and the great care that has to be used in extrapolating results observed in powder to solutions.


Asunto(s)
Leucina/análogos & derivados , Muramidasa/química , Vibración , Leucina/química , Simulación de Dinámica Molecular , Muramidasa/metabolismo
6.
Nutr Metab Cardiovasc Dis ; 21(11): 885-92, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20674312

RESUMEN

BACKGROUND AND AIM: This study aims to analyse the risk of cardiovascular events in a local cohort of patients with type 2 diabetes, and to evaluate the prognostic accuracy of four algorithms used to estimate cardiovascular risk: the Framingham study, United Kingdom Prospective Diabetes Study (UKPDS), Riskard study and Progetto Cuore. METHOD AND RESULTS: We analysed clinical charts of the Diabetes Clinics of Modena for the period 1991-95. Patients in the age range of 35-65 with type 2 diabetes and no previous cardiovascular disease were eligible. The incidence of new cardiovascular disease was compared with estimated rates deriving from the different functions. A stratification was obtained in subgroups at different cardiovascular risk, allowing comparison between the algorithms. A total of 1532 patients were eligible; women presented a worse cardiovascular risk profile. An absolute 10-year rate of cardiovascular events of 14.9% was observed. Comparing patients with events with event-free subjects, we found significant differences in systolic blood pressure, age at visit, smoking, high-density lipoprotein (HDL)-cholesterol, duration of diabetes, glycosylated haemoglobin (HbA1c) and co-morbidities. Comparing the estimated risk rate according to the different functions, Italian algorithms were more consistent with observed data; however, Progetto Cuore and Riskard show underestimation of events when applied to females. CONCLUSIONS: Estimation of cardiovascular risk is dependent on the algorithm adopted and on the baseline risk of the reference cohort. Functions designed for a specific population, including risk variables peculiar for diabetes, should be adopted to increase the performance of such functions which is clearly unsatisfactory at present.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Diabetes Mellitus Tipo 2/complicaciones , Adulto , Factores de Edad , Anciano , Algoritmos , Presión Sanguínea , HDL-Colesterol/sangre , Femenino , Hemoglobina Glucada/análisis , Humanos , Italia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Factores Sexuales , Fumar/epidemiología
7.
Sci Rep ; 11(1): 8385, 2021 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-33863976

RESUMEN

Unveiling the processes driving exotic plant invasion represent a central issue in taking decisions aimed at constraining the loss of biodiversity and related ecosystem services. The invasion success is often linked to anthropogenic land uses and warming due to climate change. We studied the responses of native versus casual and naturalised exotic species richness to land uses and climate at the landscape level, relying on a large floristic survey undertaken in North - Eastern Italy. Both climate and land use drove exotic species richness. Our results suggest that the success of plant invasion at this scale is mainly due to warm climatic conditions and the extent of urban and agricultural land, but with different effects on casual and naturalized exotic species. The occurrence of non-linear trends showed that a small percentage of extensive agricultural land in the landscape may concurrently reduce the number of exotic plant while sustaining native plant diversity. Plant invasion could be potentially limited by land management, mainly focusing on areas with extensive agricultural land use. A more consciousness land management is more and more commonly required by local administrations. According to our results, a shift of intensive to extensive agricultural land, by implementing green infrastructures, seems to be a win-win solution favouring native species while controlling the oversimplification of the flora due to plant invasion.


Asunto(s)
Agricultura/estadística & datos numéricos , Biodiversidad , Cambio Climático , Conservación de los Recursos Naturales , Especies Introducidas , Dinámica Poblacional , Desarrollo de la Planta
8.
Sci Total Environ ; 792: 148295, 2021 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-34147804

RESUMEN

The N2-fixing shrub Amorpha fruticosa L. is rapidly spreading in the dry riparian natural grasslands of Europe, altering ecosystem functions and depleting plant diversity. Alteration of the N cycle represents the key factor involved in invasions by N2-fixing plants with cascading effects on plant species richness. We hypothesized that A. fruticosa encroachment strongly impacts not only the N but also the C cycle and that the magnitude of such alterations may be modulated by soil characteristics. To test these hypotheses, we selected four river floodplains in North East of Italy and compared natural uninvaded grasslands with half invaded and completely invaded sites, based on A. fruticosa stand characteristic and relevant leaf traits and on soil properties related to soil texture and to C and N cycles. Soil organic matter mineralisation, ammonification and nitrification rates were determined. Soil nitrification increased remarkably with plant invasion while ammonification was significantly higher only in half invaded sites. Soil organic matter mineralisation, microbial biomass C sustained per soil organic C unit and nitrification positively correlated with stand age, regardless to the stage of the encroachment. Mineralisation and nitrification increased with soil organic C and total N in uninvaded and completely invaded sites, but decreased in half invaded sites. At the half invasion stage, trends in nitrification and CO2 mineralisation were transitionally reverted and remediation may be facilitated by less pronounced changes in soil properties compared to completely invaded sites. Direct effects of plant invasion are modulated by the action of soil characteristics such as soil organic C and clay contents, with soils rich in organic C showing larger nitrification and mineralisation rates.


Asunto(s)
Fabaceae , Suelo , Ecosistema , Pradera , Nitrógeno/análisis , Microbiología del Suelo
9.
Dev Dyn ; 238(10): 2641-51, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19718764

RESUMEN

Early expression of estrogen receptors (esr) and their role in regulating early expression of cyp19a1b encoding brain aromatase were examined in the brain of zebrafish. Using in toto hybridization and quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), a significant increase in the expression of esr1, esr2a, and esr2b was observed between 24 and 48 hours postfertilization (hpf). In toto hybridization demonstrated that esr2a and esr2b, but not esr1, are found in the hypothalamus. Using real-time RT-PCR, an increase in cyp19a1b mRNAs occurs between 24 and 48 hpf, indicating that expression of cyp19a1b is temporally correlated with that of esr. This increase is blocked by the pure anti-estrogen ICI182,780. Furthermore, E2 treatment of cyp19a1b-GFP (green fluorescent protein) transgenic embryos results in appearance of GFP expression in the brain as early as 25 hpf. These results indicate that basal expression of cyp19a1b expression in the brain of developing zebrafish most likely relies upon expression of esr that are fully functional before 25 hpf.


Asunto(s)
Aromatasa/metabolismo , Encéfalo , Embrión no Mamífero , Regulación del Desarrollo de la Expresión Génica , Receptores de Estrógenos/metabolismo , Proteínas de Pez Cebra/metabolismo , Pez Cebra , Animales , Animales Modificados Genéticamente , Aromatasa/genética , Encéfalo/embriología , Encéfalo/enzimología , Embrión no Mamífero/anatomía & histología , Embrión no Mamífero/enzimología , Estradiol/análogos & derivados , Estradiol/metabolismo , Antagonistas de Estrógenos/metabolismo , Fulvestrant , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptores de Estrógenos/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Pez Cebra/anatomía & histología , Pez Cebra/embriología , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética
10.
J Chem Phys ; 131(3): 034508, 2009 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-19624210

RESUMEN

The structure of deuterated liquid n-hexane has been investigated at room temperature by neutron diffraction and molecular dynamics simulations. By carrying out a careful analysis of the measurements, experimental data were obtained in very good agreement with the simulated data. This allowed a thorough analysis of the simulation results aiming at the evaluation of the partial, intra-, and intermolecular components of the n-hexane structure. We finally compare the intramolecular differential cross sections calculated from the most probable n-hexane molecular configurations with the measured and simulated data.


Asunto(s)
Hexanos/química , Simulación por Computador , Modelos Químicos , Estructura Molecular , Difracción de Neutrones , Teoría Cuántica , Temperatura
11.
Ecology ; 89(10): 2777-85, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18959315

RESUMEN

The effects of patch size and isolation on metapopulation dynamics have received wide empirical support and theoretical formalization. By contrast, the effects of patch quality seem largely underinvestigated, partly due to technical difficulties in properly assessing quality. Here we combine habitat-quality modeling with four years of demographic monitoring in a metapopulation of greater white-toothed shrews (Crocidura russula) to investigate the role of patch quality on metapopulation processes. Together, local patch quality and connectivity significantly enhanced local population sizes and occupancy rates (R2 = 14% and 19%, respectively). Accounting for the quality of patches connected to the focal one and acting as potential sources improved slightly the model explanatory power for local population sizes, pointing to significant source-sink dynamics. Local habitat quality, in interaction with connectivity, also increased colonization rate (R2 = 28%), suggesting the ability of immigrants to target high-quality patches. Overall, patterns were best explained when assuming a mean dispersal distance of 800 m, a realistic value for the species under study. Our results thus provide evidence that patch quality, in interaction with connectivity, may affect major demographic processes.


Asunto(s)
Ecosistema , Modelos Biológicos , Vigilancia de la Población/métodos , Musarañas/fisiología , Animales , Demografía , Ambiente , Análisis Factorial , Femenino , Masculino , Densidad de Población , Dinámica Poblacional , Musarañas/crecimiento & desarrollo
12.
Brain Res Bull ; 75(2-4): 274-80, 2008 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-18331884

RESUMEN

In contrast to other vertebrates, in which the adult brain shows limited adult neurogenesis, teleost fishes exhibit an unparalleled capacity to generate new neurons as adults, suggesting that their brains present a highly permissive environment for the maintenance and proliferation of adult progenitors. Here, we examine the hypothesis that one of the factors permitting establishment of this favourable environment is estradiol. Indeed, recent data showed that radial glial cells strongly expressed one of two aromatase duplicated genes. Aromatase is the estrogen-synthesizing enzyme and this observation is of great interest, given that radial glial cells are progenitor cells capable of generating new neurons. Given the well-documented roles of estrogens on cell fate, and notably on cell proliferation, these data suggest that estradiol could be involved in maintaining and/or activating these progenitors. Examination of recent data in birds and mammals suggests that the situation in fish could well be an exaggeration of a more general mechanism implicating estrogens in neurogenesis. Indeed, there is accumulating evidence that estrogens are involved in embryonic, adult or reparative neurogenesis in other vertebrates, notably in mammals.


Asunto(s)
Encéfalo/citología , Estrógenos/biosíntesis , Peces/anatomía & histología , Células Madre/metabolismo , Animales , Evolución Biológica , Proliferación Celular , Neuronas/fisiología
13.
Environ Pollut ; 151(2): 272-9, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17706847

RESUMEN

Centaurea jacea has been suggested as a potential bioindicator for ozone, but little is known about its intraspecific variation in sensitivity, especially at molecular level. The effects of ozone (200 ppb, 5 h) on sensitive and resistant lines of Centaurea have been investigated at the end of fumigation. Sensitive plants showed characteristic symptoms of injury in the form of diffuse discoloration stipples on leaves. A PCR-based approach was used to identify and isolate a partial-length cDNA coding for PAL and CHS genes. The northern analysis of PAL showed accumulation of transcript in both lines correlated with a typical increase of PAL activity (+41 and +91% in resistant and sensitive material, respectively, compared to controls). On the contrary, the transcripts of CHS, in resistant and sensitive plants, did not change after treatment. Total phenols were not affected by ozone, while anthocyanins were quickly utilised by resistant clone as antioxidant compounds.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Centaurea/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas , Ozono/toxicidad , Ácido Shikímico/metabolismo , Transducción de Señal/efectos de los fármacos , Aciltransferasas/genética , Antocianinas/análisis , Secuencia de Bases , Northern Blotting/métodos , Centaurea/genética , Centaurea/metabolismo , Exposición a Riesgos Ambientales , Genes de Plantas , Datos de Secuencia Molecular , Fenoles/análisis , Fenilanina Amoníaco-Liasa/genética , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Alineación de Secuencia , Transducción de Señal/genética
14.
Arch Intern Med ; 136(1): 30-5, 1976 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2128

RESUMEN

Nine sickle cell trait and nine control subjects underwent six-hour ammonium chloride acid loading. Maximal urine osmolality and renal hemodynamics were studied separately. Base line arterial pH, carbon dioxide pressure (Pco2), and [HCO3] were normal and comparable in the two groups. After ammonium chloride loading, urine pH decreased to 5.3 or less in all, and maximal excretion of ammonium and titratable and net acid was comparable as was urine minus blood Pco2 after bicarbonate loading. The ammonium chloride acidosis caused a small decrease in red blood cell 2,3-diphosphoglycerate levels but no alteration in oxygen pressure at 50% saturation at pH 7.4, sickling, or adverse effects. Control and sickle cell trait subjects had comparable renal hemodynamics but maximal urine osmolality was lower in sickle-cell trait subjects. Adults with sickle cell trait have diminished renal concentrating ability and normal renal acidification and hemodynamics.


Asunto(s)
Acidosis Tubular Renal/orina , Anemia de Células Falciformes/orina , Acidosis Tubular Renal/sangre , Acidosis Tubular Renal/complicaciones , Adulto , Cloruro de Amonio/metabolismo , Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/complicaciones , Bicarbonatos/metabolismo , Sangre , Dióxido de Carbono/sangre , Ácidos Difosfoglicéricos/sangre , Femenino , Humanos , Concentración de Iones de Hidrógeno , Capacidad de Concentración Renal , Masculino , Persona de Mediana Edad , Concentración Osmolar , Oxígeno/sangre , Presión Parcial , Compuestos de Amonio Cuaternario/orina
15.
J Phys Chem B ; 119(15): 5079-86, 2015 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-25803564

RESUMEN

Fully atomistic molecular dynamics (MD) simulations have been carried out on sodium dodecyl sulfate (SDS), an anionic micelle, and three cationic (CnTAB; n = 12, 14, 16) micelles, investigating the effects of size, the form of the headgroup, and chain length. They have been used to analyze neutron scattering data. MD simulations confirm the dynamical model of global motion of the whole micelle, segmental motion (headgroup and alkyl chain), and fast torsional motion associated with the surfactants that is used to analyze the experimental data. It is found that the solvent surrounding the headgroups results in their significant mobility, which exceeds that of the tails on the nanosecond time scale. The middle of the chain is found to be least mobile, consolidating the micellar configuration. This dynamical feature is similar for all the ionic micelles investigated and therefore independent of headgroup form and charge and chain length. Diffusion constants for global and segmental motion of the different micelles are consistent with experimentally obtained values as well as known structural features. This work provides a more realistic model of micelle dynamics and offers new insight into the strongly fluctuating surface of micelles which is important in understanding micelle dispersion and related functionality, like drug delivery.

16.
Endocrinology ; 138(11): 4543-51, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9348176

RESUMEN

Two different dwarf rat models with primary (dw/dw, DW) or secondary (transgenic growth retarded, WF/Tgr) GH deficiency and contrasting hypothalamic GH-releasing hormone (GHRH) and somatostatin (SRIH) expression were implanted sc with GC cells. These form encapsulated rat GH-secreting tumors that maintain high plasma rat GH levels for several weeks. In both strains, GC cell tumors stimulated growth and raised GHBP levels, without affecting pituitary GH content. In DW rats, GC cell implants increased SRIH expression in the periventricular nucleus (PeV), but not in the arcuate nucleus (ARC), whereas their high GHRH expression in ARC was decreased by GC cells. In contrast, GC cell implants in WF/Tgr rats had little effect on the already high SRIH expression in PeV or low GHRH expression in ARC, although they reduced SRIH expression in ARC. GC cell implants also reduced GH receptor expression in both ARC and PeV in the WF/Tgr dwarves. Thus, chronic GH overexposure stimulates rapid growth in both dwarf strains, but has differential hypothalamic effects in these models. This experimental approach now makes it possible to study the effects of pathophysiological concentrations of GH ranging from dwarfism to acromegaly in the same animal model.


Asunto(s)
Acromegalia/fisiopatología , Enanismo/fisiopatología , Hormona de Crecimiento Humana/fisiología , Hipotálamo/fisiopatología , Animales , Animales Modificados Genéticamente/genética , Enanismo/genética , Enanismo/metabolismo , Retroalimentación , Hormona Liberadora de Hormona del Crecimiento/genética , Hormona Liberadora de Hormona del Crecimiento/metabolismo , Hormona de Crecimiento Humana/genética , Humanos , Hipotálamo/metabolismo , Trasplante de Neoplasias , ARN Mensajero/metabolismo , Ratas , Ratas Endogámicas WF , Ratas Mutantes , Receptores de Somatotropina/metabolismo , Somatostatina/genética , Somatostatina/metabolismo , Células Tumorales Cultivadas
17.
Endocrinology ; 141(3): 967-79, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10698172

RESUMEN

Five somatostatin (SRIH) receptors (sst1-5) have been cloned. Recent anatomical evidence suggests that sst1 and sst2 may be involved in the central regulation of GH secretion. Given the lack of specific receptor antagonists, we used selective antisense oligodeoxynucleotides (ODNs) to test the hypothesis that one or both of these subtypes are involved in the intrahypothalamic network regulating pulsatile GH secretion. In mouse neuronal hypothalamic cultures the proportion of GHRH neurons coexpressing sst1 or sst2 messenger RNAs (mRNAs) was identical. In contrast, sst1 mRNAs were more often present than sst2 in SRIH-expressing neurons. Firstly, sst1 antisense ODN in vitro treatment abolished sst1, but not sst2, receptor modulation of glutamate sensitivity and decreased sst1, but not sst2, mRNAs. The reverse was true after treatment with sst2 antisense. Sense ODNs did not alter the effects of SRIH agonists. In a second series of experiments, nonanaesthetized adult male rats were infused for 120 h intracerebroventricularly with ODNs. Only the sst1 antisense ODN diminished the amplitude of ultradian GH pulses without modifying their frequency. In parallel, sst1 antisense ODN strongly diminished sst1 immunoreactivity in the anterior periventricular nucleus and median eminence, as well as sstl periventricular nucleus mRNA levels. The effectiveness of the sst2 antisense ODN was attested by the inhibition of hypothalamic binding of [125I]Tyr0-D-Trp8-SRIH. Scrambled ODNs had no effect on GH secretion or on sst mRNAs or SRIH binding levels. These results favor a preferential involvement of sst1 receptors in the intrahypothalamic regulation of GH secretion by SRIH.


Asunto(s)
Hormona del Crecimiento/metabolismo , Hipotálamo/fisiología , Red Nerviosa/fisiología , Oligodesoxirribonucleótidos Antisentido/farmacología , Receptores de Somatostatina/fisiología , Animales , Células Cultivadas , Electrofisiología , Ácido Glutámico/farmacología , Inmunohistoquímica , Hibridación in Situ , Inyecciones Intraventriculares , Masculino , Ratones , Técnicas de Placa-Clamp , Ratas , Ratas Wistar , Receptores de Somatostatina/biosíntesis , Receptores de Somatostatina/genética , Receptores de Somatostatina/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Somatostatina/metabolismo
18.
Pediatrics ; 84(2): 281-4, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2748256

RESUMEN

A new topical anesthetic ointment (EMLA, "eutectic mixture of prilocaine and lidocaine was studied in a double-blind, placebo-controlled trial to evaluate its efficiency in alleviating pain associated with venous, subcutaneous drug reservoir and lumbar punctures in children. Pain intensity was scored by the children themselves, using a visual analogue scale in which 0 corresponded to absence of sensation and 10 to the worst imaginable painful sensation. Venipunctures were performed on 18 children (6.1 to 12.2 years of age) equally divided in the study and control groups; EMLA cream was associated with lesser pain scores than those with placebo (means +/- SD: 2.8 +/- 2.4 vs 6.8 +/- 2.1, P less than .01). A crossover trial was used in the studies of subcutaneous drug reservoir and lumbar punctures, eight children (6.1 to 15.1 years of age) were tested for subcutaneous drug reservoir punctures; pain induced by this procedure was rated at 3.9 +/- 2.2 with placebo compared with 1.2 +/- 1.8 with EMLA cream (P less than .04). In lumbar punctures (14 children studied, 5.5 to 15.3 years of age), EMLA cream was again associated with less pain (1.9 +/- 1.9) than was placebo (5.6 +/- 3.0, P less than .01). It was concluded that the use of EMLA cream substantially reduces pain caused by venous, subcutaneous drug reservoir, and lumbar punctures in children and may therefore be offered to young patients, particularly those repeatedly submitted to such procedures.


Asunto(s)
Anestésicos Locales/uso terapéutico , Lidocaína/uso terapéutico , Dolor/prevención & control , Prilocaína/uso terapéutico , Punciones , Adolescente , Venodisección , Niño , Preescolar , Combinación de Medicamentos/uso terapéutico , Femenino , Humanos , Inyecciones Subcutáneas , Combinación Lidocaína y Prilocaína , Masculino , Pomadas , Punción Espinal
19.
J Endocrinol ; 152(3): 431-6, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9071964

RESUMEN

Involvement of endogenous corticotropin releasing hormone (CRH) in the regulation of spontaneous growth hormone (GH) secretion was investigated. A CRH antagonist, alpha helical CRH 9-41, was intracerebroventricularly infused for 36 h at a rate of 1 microgram/0.5 microliter/h to freely moving, cannulated adult male rats. Serial blood samples were drawn every 20 min for the last 8 hours of alpha helical CRH 9-41 infusion. The treatment induced a marked increase in GH peak amplitude without affecting either trough levels or numbers of peaks. In parallel, levels of growth hormone releasing hormone (GHRH) mRNA in the arcuate nucleus, but not of somatotropin release inhibiting hormone (SRIH) mRNA in the periventricular and arcuate nuclei, were increased. These data suggest that, in addition to its action in the stress-induced inhibition of GH secretion through regulation of periventricular SRIH neurons, CRH can also act as a modulator of endogenous GH secretion through regulation of arcuate GHRH neurons. Whether the modulatory effects of CRH on GHRH neurons are direct or indirect remains to be established.


Asunto(s)
Núcleo Arqueado del Hipotálamo/metabolismo , Hormona Liberadora de Corticotropina/administración & dosificación , Hormona Liberadora de Hormona del Crecimiento/genética , Hormona del Crecimiento/metabolismo , Antagonistas de Hormonas/administración & dosificación , Fragmentos de Péptidos/administración & dosificación , ARN Mensajero/metabolismo , Hormona Adrenocorticotrópica/metabolismo , Animales , Ventrículos Cerebrales , Hormona Liberadora de Corticotropina/farmacología , Antagonistas de Hormonas/farmacología , Hibridación in Situ , Masculino , Fragmentos de Péptidos/farmacología , ARN Mensajero/análisis , Radioinmunoensayo , Ratas , Ratas Wistar , Somatostatina/genética
20.
Res Microbiol ; 151(5): 353-60, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10919515

RESUMEN

The green fluorescent protein (GFP) of the jellyfish Aequorea victoria is a useful reporter molecule for monitoring in vivo gene expression in eukaryotic and prokaryotic cells. We constructed a series of GFP vectors for in situ detection of the intracellular pathogen Listeria monocytogenes. The gfp-mutl gene, which encodes a red-shifted GFP, was transcriptionally fused to a strong L. monocytogenes promoter and inserted into various Escherichia coli-Listeria shuttle vectors: i) the integrative monocopy plasmid pAT113; ii) the low copy number plasmid pTCV-Exl; iii) the high copy number plasmid pAT18. Listeria cells harboring pNF6 and pNF7, constructed from pAT113 and pTCV-Exl, respectively, gave low fluorescence intensities, and were optically detected in cultured macrophages, but not in tissue sections. The fluorescence of Listeria with the pAT18 derivative pNF8 was about 40 times greater than that with pNF6 and 15 times greater than that with pNF7. Listeria cells harboring pNF8 were readily detected in both cultured macrophages and tissue sections. Constructed GFP vectors did not affect the virulence of L. monocytogenes in a murine model of infection.


Asunto(s)
Vectores Genéticos , Listeria monocytogenes/aislamiento & purificación , Proteínas Luminiscentes/metabolismo , Animales , Western Blotting , Conjugación Genética , Escherichia coli/genética , Escherichia coli/metabolismo , Femenino , Citometría de Flujo , Proteínas Fluorescentes Verdes , Listeria monocytogenes/genética , Listeria monocytogenes/metabolismo , Listeria monocytogenes/patogenicidad , Listeriosis/microbiología , Listeriosis/fisiopatología , Proteínas Luminiscentes/genética , Macrófagos/microbiología , Ratones , Microscopía Fluorescente , Plásmidos/genética , Virulencia
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