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1.
Artículo en Inglés | MEDLINE | ID: mdl-39137353

RESUMEN

Introduction: Cannabis cultivars were usually categorized based on their genetic profile as sativa, indica, or hybrid types. However, these three criteria do not allow sufficient differentiation between the numerous varieties of cannabis strains. Furthermore, this classification is based on morphological and bio-geographical properties of the plants and does not represent the chemical composition of different cultivars. The concentration of cannabinoids and terpenes are crucial for the pharmacological effect, not only because of the known entourage effect, and therefore needs to be considered by categorization. Materials and Methods: A total of 140 medicinal cannabis flowers available on the German market were analyzed regarding their individual terpene profile using GC-MS analysis. Statistical evaluation was performed to investigate correlations and data relations as well as for clustering. Results: Multivariate analysis showed correlations between individual terpenes. However, there was no statistical correlation between terpene profiles and their respective genetic profile. Terpene profiles of sativa, indica, and hybrid strains are quite heterogenous and clearly showed that there is no relation between terpenes and the estimated pharmacological effect. As a result, we suggest a new classification system based on individual terpene profiles to faster a comprehensive understanding of the expected medical effect. Discussion: Considering main terpenes, we established a concept of six clusters with various terpene profiles being attributed to different medicinal applications. We excluded tetrahydrocannabinol (THC) and cannabidiol (CBD) content from clustering as most of the strains were THC dominant and therefore distort the results. Our pattern of strains with similar terpene profiles might refine the existing classes of chemotypes with different THC:CBD content. Conclusion: The categorization of cannabis strains based on their terpene profiles allows a clearer, finer and, above all, more meaningful classification than the existing sativa/indica classification. Due to the entourage effect and the interactions between cannabinoids and terpenes, this group of substances is also given the necessary consideration when selecting the right medicine for the individual. Within the next steps, further studies are needed with the aim of mapping clinical validated effects to our chemovars. If it is possible to correlate therapy of symptoms to specific chemical profiles personalized cannabinoid therapy will be possible.

2.
EFSA J ; 15(1): e04687, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32625275

RESUMEN

Highly pathogenic avian influenza (HPAI) H5N8 is currently causing an epizootic in Europe, infecting many poultry holdings as well as captive and wild bird species in more than 10 countries. Given the clear clinical manifestation, passive surveillance is considered the most effective means of detecting infected wild and domestic birds. Testing samples from new species and non-previously reported areas is key to determine the geographic spread of HPAIV H5N8 2016 in wild birds. Testing limited numbers of dead wild birds in previously reported areas is useful when it is relevant to know whether the virus is still present in the area or not, e.g. before restrictive measures in poultry are to be lifted. To prevent introduction of HPAIV from wild birds into poultry, strict biosecurity implemented and maintained by the poultry farmers is the most important measure. Providing holding-specific biosecurity guidance is strongly recommended as it is expected to have a high impact on the achieved biosecurity level of the holding. This is preferably done during peace time to increase preparedness for future outbreaks. The location and size of control and in particular monitoring areas for poultry associated with positive wild bird findings are best based on knowledge of the wider habitat and flight distance of the affected wild bird species. It is recommended to increase awareness among poultry farmers in these established areas in order to enhance passive surveillance and to implement enhanced biosecurity measures including poultry confinement. There is no scientific evidence suggesting a different effectiveness of the protection measures on the introduction into poultry holdings and subsequent spread of HPAIV when applied to H5N8, H5N1 or other notifiable HPAI viruses.

3.
Mucosal Immunol ; 7(4): 892-904, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24345804

RESUMEN

Lymphoid organ hypertrophy is a hallmark of localized infection. During the inflammatory response, massive changes in lymphocyte recirculation and turnover boost lymphoid organ cellularity. Intriguingly, the exact nature of these changes remains undefined to date. Here, we report that hypertrophy of Salmonella-infected Peyer's patches (PPs) ensues from a global "shutdown" of lymphocyte egress, which traps recirculating lymphocytes in PPs. Surprisingly, infection-induced lymphocyte sequestration did not require previously proposed mediators of lymphoid organ shutdown including type I interferon receptor and CD69. In contrast, following T-cell receptor-mediated priming, CD69 was essential to selectively block CD4(+) effector T-cell egress. Our findings segregate two distinct lymphocyte sequestration mechanisms, which differentially rely on intrinsic modulation of lymphocyte egress capacity and inflammation-induced changes in the lymphoid organ environment.


Asunto(s)
Antígenos CD/metabolismo , Antígenos de Diferenciación de Linfocitos T/metabolismo , Lectinas Tipo C/metabolismo , Linfocitos/metabolismo , Ganglios Linfáticos Agregados/inmunología , Ganglios Linfáticos Agregados/patología , Receptores de Interferón/metabolismo , Animales , Hipertrofia , Ligandos , Recuento de Linfocitos , Linfocitos/inmunología , Ratones , Ratones Noqueados , Ratones Transgénicos , Ganglios Linfáticos Agregados/microbiología , Salmonella/inmunología , Infecciones por Salmonella/inmunología , Infecciones por Salmonella/metabolismo , Receptores Toll-Like/metabolismo
4.
Exp Clin Endocrinol Diabetes ; 118(8): 473-7, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20198559

RESUMEN

Dipeptidyl-peptidase (DPP)-4, which catalizes the degradation of the insulinotropic incretin glucagon-like-peptide (GLP)-1, and the DPP-4 like enzyme attractin are involved in activation of T-lymphocytes and monocytes. Recently, it has been demonstrated, that the risk for certain infections is increased in type 2 diabetic patients under DPP-4 inhibitor treatment. The aim of the present study was to examine the expression of DPP-4 and attractin in circulating blood monocytes of obese and type 2 diabetic subjects. Monocytes were isolated by CD14-antibody based magnetic cell sorting from blood samples of 17 lean controls, 20 obese, non-diabetic subjects and 19 obese patients with type 2 diabetes. FACS analysis was performed to test purity of the cell preparations. Expression was measured by multiplex RT-PCR on RNA-level. DPP-4 and attractin were detectable in human circulating monocytes with attractin being expressed at higher levels compared to DPP-4. Both enzymes were significantly higher expressed in circulating blood monocytes of obese subjects compared to lean controls. In contrast, type 2 diabetes did not significantly affect expression levels. Finally, neither DPP-4 nor attractin expression was altered by sitagliptin or insulin treatment. In conclusion, our data demonstrate, that expressions of DPP-4 and attractin in circulating blood monocytes of human subjects are influenced by metabolic abnormalities with obesity being an important factor.


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Dipeptidil Peptidasa 4/sangre , Proteínas de la Membrana/sangre , Monocitos/enzimología , Obesidad/sangre , Índice de Masa Corporal , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/enzimología , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Femenino , Péptido 1 Similar al Glucagón/sangre , Péptido 1 Similar al Glucagón/metabolismo , Humanos , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Receptores de Lipopolisacáridos/análisis , Masculino , Persona de Mediana Edad , Obesidad/enzimología , Pirazinas/uso terapéutico , Fosfato de Sitagliptina , Triazoles/uso terapéutico
5.
Horm Metab Res ; 42(4): 268-73, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20091460

RESUMEN

Low-grade inflammation is important in the development of obesity related pathologies such as insulin resistance and type 2 diabetes, and also cardiovascular disease. Visfatin/PBEF/Nampt and resistin are proinflammatory adipokines secreted from adipocytes, monocytes, and macrophages, and have been linked to atherosclerotic plaque formation, recently. The aim of the present study was to investigate if the expression of these molecules in circulating blood monocytes is altered in obese and/or type 2 diabetic human subjects. Monocytes were isolated by CD14-antibody based magnetic cell sorting from blood samples of 17 lean controls, 20 obese nondiabetic subjects, and 19 obese patients with type 2 diabetes. FACS analysis was performed to test purity of the cell preparations. Expression of the different adipokines was measured by multiplex real-time PCR on RNA-level. Visfatin/PBEF/Nampt was found to be very strongly expressed in monocytes, whereas resistin levels were significantly lower. Furthermore, visfatin/PBEF/Nampt expression was significantly upregulated in obese type 2 diabetic patients, whereas obese nondiabetics exhibited similar levels compared to lean controls, indicating that visfatin/PBEF/Nampt levels are related to type 2 diabetes rather than to obesity. In contrast, resistin expression displayed a different pattern being significantly increased in obese subjects compared to controls but not related to type 2 diabetes. These data suggest a differential role for these two proinflammatory adipokines in linking metabolic diseases to atherosclerosis with visfatin/PBEF/Nampt being more important in patients with type 2 diabetes and resistin in obese but nondiabetic human subjects.


Asunto(s)
Citocinas/sangre , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/complicaciones , Monocitos/enzimología , Nicotinamida Fosforribosiltransferasa/sangre , Obesidad/sangre , Obesidad/complicaciones , Resistina/sangre , Antropometría , Citocinas/genética , Diabetes Mellitus Tipo 2/enzimología , Diabetes Mellitus Tipo 2/genética , Femenino , Glucosa/farmacología , Humanos , Inflamación/sangre , Inflamación/complicaciones , Insulina/farmacología , Receptores de Lipopolisacáridos/metabolismo , Masculino , Persona de Mediana Edad , Nicotinamida Fosforribosiltransferasa/genética , Obesidad/enzimología , Obesidad/genética , Resistina/genética
6.
Gene Ther ; 16(3): 359-66, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19052633

RESUMEN

Replicon plasmids encoding an alphavirus RNA replicase constitute an alternative to conventional DNA plasmids with promise for DNA vaccination in humans. Replicase activity amplifies the levels of transgene mRNA through a copying process involving double-stranded (ds) RNA intermediates, which contribute to vaccine immunogenicity by activating innate antiviral responses. Toll-like receptor 3 (TLR3) is a dsRNA innate immune receptor expressed by antigen-presenting dendritic cells (DCs). Here, we test the hypothesis that TLR3 is necessary for the immunogenicity of replicon plasmid-based DNA vaccines. We show that mouse CD8 alpha(+) DC phagocytose dying replicon plasmid-transfected cells in vitro and are activated in a TLR3-dependent manner by dsRNA present within those cells. However, we find that cytotoxic T-cell responses to a replicon plasmid intramuscular vaccine are not diminished in the absence of TLR3 in vivo. Our results underscore the potential role of TLR3 in mediating immune activation by dsRNA-bearing replicon plasmid-transfected cells and indicate that other innate sensing pathways can compensate for TLR3 absence in vivo.


Asunto(s)
Replicón/inmunología , Receptor Toll-Like 3/inmunología , Vacunas de ADN/inmunología , Animales , Apoptosis/inmunología , Antígenos CD8/análisis , Linfocitos T CD8-positivos/inmunología , Chlorocebus aethiops , Técnicas de Cocultivo , Citotoxicidad Inmunológica/inmunología , Células Dendríticas/inmunología , Expresión Génica/inmunología , Genes Transgénicos Suicidas , Vectores Genéticos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Plásmidos/inmunología , ARN Bicatenario/biosíntesis , Bazo/inmunología , Transfección , Vacunación/métodos , Células Vero
7.
Opt Express ; 15(15): 9107-12, 2007 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-19547250

RESUMEN

Easy to handle light sources with non-classical emission features are strongly demanded in the growing field of quantum communication. We report on single-photon emission from an electrically pumped quantum dot with unmatched spectral purity, making spatial or spectral filtering dispensable.

8.
Regul Toxicol Pharmacol ; 44(2): 172-81, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16356615

RESUMEN

A major problem in risk assessment is the quantification of uncertainties. A probabilistic model was developed to consider uncertainties in the effect assessment of hazardous substances at the workplace. Distributions for extrapolation factors (time extrapolation, inter- and intraspecies extrapolation) were determined on the basis of appropriate empirical data. Together with the distribution for the benchmark dose obtained from substance-specific dose-response modelling for the exemplary substances 2,4,4-trimethylpentene (TMP) and aniline, they represent the input distributions for probabilistic modelling. These distributions were combined by Monte Carlo simulation. The resulting target distribution describes the probability that an aspired protection level for workers is achieved at a certain dose and the uncertainty associated with the assessment. In the case of aniline, substance-specific data on differences in susceptibility (between species; among humans due to genetic polymorphisms of N-acetyltransferase) were integrated in the model. Medians of the obtained target distributions of the basic models for TMP and aniline, but not of the specific aniline model are similar to deterministically derived reference values. Differences of more than one order of magnitude between the medians and the 5th percentile of the target distributions indicate substantial uncertainty associated with the effect assessment of these substances. The probabilistic effect assessment model proves to be a practical tool to integrate quantitative information on uncertainty and variability in hazard characterisation.


Asunto(s)
Alquenos/toxicidad , Compuestos de Anilina/toxicidad , Sustancias Peligrosas/toxicidad , Modelos Estadísticos , Exposición Profesional , Animales , Humanos , Método de Montecarlo , Ratas , Medición de Riesgo , Incertidumbre , Lugar de Trabajo
9.
Phys Rev Lett ; 95(22): 229801; author reply 229802, 2005 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-16384274
10.
Pathol Biol (Paris) ; 51(2): 67-8, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12801803

RESUMEN

Dendritic cells (DC) initiate T cell responses and produce cytokines and other molecules that can regulate the class adaptive immunity. It is increasingly clear that DC in vivo are in a "resting" state and require exogenous signals to transit into an "effector" state in which they can prime T cells. Much of this DC activation process appears to be regulated by infection. Exposure of murine DC to certain pathogens or their products triggers DC migration to T cell areas of secondary lymphoid tissues, improves MHC presentation and increases DC co-stimulatory potential. Pathogen recognition can also initiate cytokine production and/or condition DC to produce cytokines in response to subsequent T cell feedback signals delivered via CD40 and similar receptors. Recognition of pathogens by DC is largely dependent on Toll-like receptors (TLRs). Interestingly, mouse splenic CD8alpha+ and CDalpha-CD4- DC have the ability to produce either IL-12 p70 or IL-10 depending on the nature of the pathogen encountered. In contrast, CD4+ DC seem incapable of producing IL-12 p70. Thus, the nature of the pathogen can dictate the type of cytokine that is made by some DC subsets, allowing them to prime distinct types of immune responses. Overall, DC display significant plasticity in their ability to respond to infection and direct adaptive immunity.


Asunto(s)
Antígenos Bacterianos/inmunología , Antígenos Fúngicos/inmunología , Antígenos Virales/inmunología , Células Dendríticas/inmunología , Animales , Citocinas/inmunología , Células Dendríticas/clasificación , Humanos , Ratones , Especificidad de la Especie , Bazo/citología , Bazo/inmunología , Células TH1/inmunología , Células Th2/inmunología
12.
Berl Munch Tierarztl Wochenschr ; 114(5-6): 218-21, 2001.
Artículo en Alemán | MEDLINE | ID: mdl-11413718

RESUMEN

It is reported of botanical intoxications in 1379 ruminants (dairy cattle, beef cattle and ewes) in north-eastern Germany. The intoxications of these animals were caused by consumption of the following plants: meadow saffron (Colchicum autumnale L.), cowbane (Cicuta virosa L.), sweet clover (Melilotus alba MED.), sheep's sorrel (Rumex acetosella L.), bracken (Pteridium aquilinum KUHN) and St. John's wort (Hypericum perforatum L.). In all the five described cases animals died as a result of plant intoxications. The authors come to the conclusion that periodical inspections of the meadows are necessary, checking the plants in cooperation with veterinary surgeons.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Intoxicación por Plantas/veterinaria , Plantas Tóxicas/clasificación , Enfermedades de las Ovejas/epidemiología , Animales , Bovinos , Enfermedades de los Bovinos/etiología , Enfermedades de los Bovinos/prevención & control , Alemania/epidemiología , Intoxicación por Plantas/epidemiología , Intoxicación por Plantas/prevención & control , Ovinos , Enfermedades de las Ovejas/etiología , Enfermedades de las Ovejas/prevención & control
13.
Fresenius J Anal Chem ; 371(8): 1070-5, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11798099

RESUMEN

A new axially viewed ICP optical emission spectrometer featuring an argon-filled optic and CCD detectors was evaluated for the application of prominent spectral lines in the 125-180 nm range. This wavelength range was investigated for several analytical applications of inductively coupled plasma optical emission spectrometry (ICP-OES). There are different advantages for the application of spectral lines below 180 nm. A number of elements, such as Al, Br, Cl, Ga, Ge, I, In, N, P, Pb, Pt, S and Te, were found to have the most intense spectral lines in the wavelength range from 125-180 nm. Compared with lines above 180 nm higher signal-to-background ratios were found. Low limits of detection using pneumatic nebulization of aqueous solutions for sample introduction were calculated for Al II 167.080 nm (0.04 microg L(-1)), Br I 154.065 nm (9 microg L(-1)), Cl I 134.724 nm (19 microg L(-1)), Ga II 141.444 nm (0.8 microg L(-1)), Ge II 164.919 nm (1.3 microg L(-1)), II 142.549 nm (13 microg L(-1)), In II 158.583 nm (0.2 microg L(-1)), P I 177.500 nm (0.9 microg L(-1)), Pb II 168.215 nm (1.5 microg L(-1)), Pt II 177.709 nm (2.6 microg L(-1)), S I 180.731 nm (1.9 microg L(-1)) and Te I 170.00 nm (4.6 microg L(-1)). Numerous application examples for the use of those lines and other important spectral lines below 180 nm are given. Because of fewer emission lines from transition elements, such as Fe, Co, Cr, lines below 180 nm often offer freedom from spectral interferences. Additional lines of lower intensity for the determination of higher elemental concentrations are also available in the vacuum ultraviolet spectral range. This is specially useful when the concentrations are not in the linear range of calibration curves obtained with commonly used lines.

15.
Immunity ; 13(4): 453-62, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11070164

RESUMEN

CD40 ligation triggers IL-12 production by dendritic cells (DC) in vitro. Here, we demonstrate that CD40 cross-linking alone is not sufficient to induce IL-12 production by DC in vivo. Indeed, resting DC make neither the IL-12 p35 nor IL-12 p40 subunits and express only low levels of CD40. Nevertheless, after DC activation by microbial stimuli that primarily upregulate IL-12 p40 and augment CD40 expression, CD40 ligation induces a significant increase in IL-12 p35 and IL-12 p70 heterodimer production. Similarly, IL-12 p70 is produced during T cell activation in the presence but not in the absence of microbial stimuli. Thus, production of bioactive IL-12 by DC can be amplified by T cell-derived signals but must be initiated by innate signals.


Asunto(s)
Antígenos de Protozoos/administración & dosificación , Antígenos de Protozoos/inmunología , Antígenos CD40/fisiología , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Interleucina-12/biosíntesis , Transducción de Señal/inmunología , Células 3T3 , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes Inmunológicos/fisiología , Animales , Anticuerpos Monoclonales/administración & dosificación , Antígenos CD40/biosíntesis , Antígenos CD40/inmunología , Células Cultivadas , Células Dendríticas/citología , Células Dendríticas/parasitología , Dimerización , Femenino , Inyecciones Intraperitoneales , Inyecciones Intravenosas , Interleucina-12/metabolismo , Interfase/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Ratones SCID , Ratones Transgénicos , Linfocitos T/inmunología , Toxoplasma/inmunología , Regulación hacia Arriba/inmunología
16.
Br J Pharmacol ; 131(3): 423-32, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11015291

RESUMEN

The steady state levels of the messenger RNA (mRNA) of eight GABA(A) receptor subunits, five glutamate receptor subunits and seven enzymes involved in the synthesis of glutamate and GABA were measured in eight regions of rat brain in a recently developed animal model of 'behavioural dependence' on ethanol. 'Behavioural dependence' including loss of control was induced by offering the rats the choice between ethanol and water over a 9-month period (Group A). This group was compared with a group given the choice between ethanol and water for only 2 months (not yet 'behaviourally dependent', Group B), a group forced to consume ethanol as sole fluid over a 9-month period (also not 'behaviourally dependent', Group C) and ethanol-naive control rats (Group D). All groups were sacrificed 1 month after the ethanol was withdrawn. The mRNA concentrations of all eight GABA receptor subunits, four out of the five subunits of different glutamate receptors and those of seven enzymes involved in GABA and glutamate production were reduced almost exclusively in the parieto-occipital cortex in Groups A and B, but not Group C. These data suggest that the synthesis of glutamate and GABA and the activities of their respective neurons are selectively impaired in the parieto-occipital cortex in the groups having consumed ethanol in a free-choice design, in which its rewarding properties can better take effect than after forced administration. As the parieto-occipital cortex is believed to contain emotional memory structures, it may be hypothesized that the glutamatergic and GABAergic neuronal systems in this area are involved in the development of memory for reward from ethanol. However, they are not specifically associated with 'behavioural dependence'.


Asunto(s)
Sistema Nervioso Central/metabolismo , Ácido Glutámico/metabolismo , Receptores de GABA/genética , Receptores de Glutamato/genética , Ácido gamma-Aminobutírico/metabolismo , Animales , Astrocitos/metabolismo , Etanol , Expresión Génica , Masculino , Mitocondrias/metabolismo , Neurotransmisores/metabolismo , Ratas , Ratas Wistar , Receptores de GABA/biosíntesis , Receptores de Glutamato/biosíntesis
17.
J Exp Med ; 190(12): 1897-902, 1999 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-10601364

RESUMEN

The house dust mite Dermatophagoides pteronyssinus allergen Der p 1 is the most immunodominant allergen involved in the expression of dust mite-specific immunoglobulin (Ig)E-mediated hypersensitivity. The reason for this potent IgE-eliciting property of Der p 1 remains unknown, but there is mounting in vitro evidence linking the allergenicity of Der p 1 to its cysteine protease activity. Here we demonstrate for the first time that immunization of mice with proteolytically active Der p 1 results in a significant enhancement in total IgE and Der p 1-specific IgE synthesis compared with animals immunized with Der p 1 that was irreversibly blocked with the cysteine protease inhibitor E-64. We conclude that the proteolytic activity of Der p 1 is a major contributor to its allergenicity.


Asunto(s)
Alérgenos/inmunología , Cisteína Endopeptidasas/inmunología , Glicoproteínas/inmunología , Inmunoglobulina E/inmunología , Alérgenos/metabolismo , Animales , Anticuerpos/inmunología , Antígenos/inmunología , Antígenos Dermatofagoides , Cisteína Endopeptidasas/metabolismo , Glicoproteínas/metabolismo , Inmunoglobulina E/biosíntesis , Ratones , Ácaros
18.
Immunity ; 11(5): 637-47, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10591188

RESUMEN

Interleukin-12 plays a major role in immunity to intracellular pathogens by governing the development of IFNgamma-dependent host resistance. Nevertheless, unregulated IL-12 synthesis can lead to immunopathology, an outcome prevented by the concurrent expression of interleukin-10. Dendritic cells (DC) are an important source of the initial IL-12 stimulated by microbial agents. Here, we show that, following systemic triggering, DC can no longer be restimulated to produce IL-12 in vivo while continuing to respond in vitro. When infected with Toxoplasma gondii during this refractory state, mice mount impaired acute IFNgamma responses and, in the case of IL-10-deficient animals, are protected from cytokine-induced mortality. These findings demonstrate a previously unrecognized form of immunologic paralysis involving DC that can protect from infection-induced immunopathology.


Asunto(s)
Antígenos de Protozoos/inmunología , Células Dendríticas/inmunología , Interleucina-12/fisiología , Modelos Inmunológicos , Toxoplasma/inmunología , Toxoplasmosis Animal/inmunología , Animales , Antígenos de Protozoos/farmacología , Células Cultivadas , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Interacciones Huésped-Parásitos , Interferón gamma/biosíntesis , Interferón gamma/deficiencia , Interleucina-10/deficiencia , Interleucina-10/genética , Interleucina-12/biosíntesis , Interleucina-12/deficiencia , Interleucina-12/genética , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Ratones Noqueados , Bazo/inmunología , Toxoplasmosis Animal/complicaciones , Toxoplasmosis Animal/patología
20.
Am Heart J ; 137(5): 887-94, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10220638

RESUMEN

BACKGROUND: Heart transplantation is associated with a reduction of the neurohumoral activation seen in patients with severe congestive heart failure. In this study, we investigated whether pharmacologically induced complex hemodynamic improvement during assessment of reversibility of pulmonary hypertension with a phosphodiesterase inhibitor is able to induce neurohormonal changes of diagnostic importance. METHODS AND RESULTS: Twenty-one patients with New York Heart Association class III-IV heart failure underwent infusion of 3 mg/kg enoximone over a period of 30 minutes. Before and after drug infusion, we determined the plasma concentrations of atrial natriuretic peptide, endothelin-I, angiotensin-II, aldosterone, norepinephrine, epinephrine, and angiotensin-converting enzyme activity sampled from a peripheral vein and the pulmonary artery. In addition to the expected significant reduction of pulmonary hypertension and enhancement of cardiac output, increased levels of the vasoconstrictors endothelin-I, angiotensin-II, and norepinephrine were observed. Aldosterone fell after enoximone infusion; a higher baseline aldosterone level correlated to the degree of reduction of the pulmonary arteriolar resistance by enoximone. Baseline atrial natriuretic peptide levels correlated with parameters, indicating the severity of heart failure. However, the plasma concentration of this peptide did not change significantly after enoximone infusion. CONCLUSIONS: Acute hemodynamic improvement after enoximone bolus in candidates for heart transplantation is not accompanied by a reduction of the enhanced neurohumoral activity in these patients. The reaction of the investigated hormones cannot predict the individual degree of reversibility of pulmonary hypertension.


Asunto(s)
Factor Natriurético Atrial/sangre , Enoximona/administración & dosificación , Hipertensión Pulmonar/sangre , Inhibidores de Fosfodiesterasa/administración & dosificación , Angiotensina II/sangre , Biomarcadores/sangre , Cateterismo Cardíaco , Catecolaminas/sangre , Endotelina-1/sangre , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/tratamiento farmacológico , Hemodinámica/efectos de los fármacos , Humanos , Hipertensión Pulmonar/tratamiento farmacológico , Hipertensión Pulmonar/etiología , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Peptidil-Dipeptidasa A/sangre , Pronóstico , Arteria Pulmonar , Venas Pulmonares , Índice de Severidad de la Enfermedad
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