RESUMEN
Large-scale non-kin cooperation is a unique ingredient of human success. This type of cooperation is challenging to explain in a world of self-interested individuals. There is overwhelming empirical evidence from different disciplines that reputation and gossip promote cooperation in humans in different contexts. Despite decades of research, important details of reputation systems are still unclear. Our goal with this theme issue is to promote an interdisciplinary approach that allows us to explore and understand the evolution and maintenance of reputation systems with a special emphasis on gossip and honest signalling. The theme issue is organized around four main questions: What are the necessary conditions for reputation-based systems? What is the content and context of reputation systems? How can reputations promote cooperation? And, what is the role of gossip in maintaining reputation systems and thus cooperation? This article is part of the theme issue 'The language of cooperation: reputation and honest signalling'.
Asunto(s)
Comunicación , Conducta Cooperativa , Humanos , LenguajeRESUMEN
It seems obvious that as the benefits of cooperation increase, the share of cooperators in the population should also increase. It is well known that positive assortment between cooperative types, for instance in spatially structured populations, provide better conditions for the evolution of cooperation than complete mixing. This study demonstrates that, assuming positive assortment, under most conditions higher cooperation benefits also increase the share of cooperators. On the other hand, under a specified range of payoff values, when at least two payoff parameters are modified, the reverse is true. The conditions for this paradox are determined for two-person social dilemmas: the Prisoner's Dilemma, the Hawks and Doves game, and the Stag Hunt game, assuming global selection and positive assortment.
Asunto(s)
Conducta Cooperativa , Teoría del Juego , Modelos Teóricos , Altruismo , Evolución Biológica , Conducta Competitiva , Simulación por Computador , Humanos , Dinámica Poblacional , Conducta SocialRESUMEN
The authors report on 18 members of four generations of an alkaptonuric family. All three males in the third generation are clinically affected; two members of the family tree have undergone major joint surgery.
Asunto(s)
Alcaptonuria/genética , Genes Recesivos , Artropatías/genética , Ocronosis/genética , Alcaptonuria/complicaciones , Familia , Femenino , Humanos , Artropatías/etiología , Artropatías/cirugía , Masculino , Persona de Mediana Edad , Ocronosis/complicaciones , Linaje , Huesos Pélvicos/diagnóstico por imagen , Radiografía , Columna Vertebral/diagnóstico por imagenRESUMEN
Individual B lymphocytes normally express immunoglobulin (Ig) proteins derived from single Ig heavy chain (H) and light chain (L) alleles. Allelic exclusion ensures monoallelic expression of Ig genes by each B cell to maintain single receptor specificity. Here we provide evidence that at later stages of B cell development, additional mechanisms may contribute to prioritizing expression of single IgH and IgL alleles. Fluorescent in situ hybridization analysis of primary splenic B cells isolated from normal and genetically manipulated mice showed that endogenous IgH, kappa and lambda alleles localized to different subnuclear environments after activation and had differential expression patterns. However, this differential recruitment and expression of Ig alleles was not typically seen among transformed B cell lines. These data raise the possibility that epigenetic factors help maintain the monoallelic expression of Ig.
Asunto(s)
Linfocitos B/inmunología , Núcleo Celular/genética , Genes de Inmunoglobulinas , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas Ligeras de Inmunoglobulina/genética , Alelos , Animales , Línea Celular Transformada , Células Cultivadas , Centrómero/química , Células Clonales , Reordenamiento Génico de Linfocito B , Cadenas Pesadas de Inmunoglobulina/biosíntesis , Cadenas Ligeras de Inmunoglobulina/biosíntesis , Cadenas kappa de Inmunoglobulina/biosíntesis , Cadenas kappa de Inmunoglobulina/genética , Hibridación Fluorescente in Situ , Activación de Linfocitos , Ratones , ARN Mensajero/biosíntesis , Bazo/inmunologíaRESUMEN
The influence of costimulation on the activation of naive CD8+ T cells and thymocytes was studied in vitro using H-Y-specific TCR-transgenic mice and H-Y antigenic peptide. Using a variety of physiological APC types, the activation of naive CD8+ T cells depended strictly on costimulation, which could not be substituted by high epitope density. T cell activation is known to be regulated by the interactions between CD86/CD80 and CD28/CD152, although it remains unclear whether the B7 isoforms have distinct roles. Addition of soluble anti-CD86 Ab led to profound inhibition of T cell reactivity, further confirming the importance of costimulation in naive CD8+ T cell activation. Finally, TCR engagement in the absence of costimulation had no effect on the subsequent reactivity of peripheral naive transgenic CD8+ T cells, but induced nonresponsiveness in mature CD8+ transgenic thymocytes. Collectively, these results demonstrate the importance of costimulation for naive CD8+ T cell activation, suggest that CD80 and CD86 can mediate opposing effects, possibly due to differential interaction with CD152 and CD28, and indicate differences in the sensitivity of immature vs mature CD8+ T cells to the induction of nonresponsiveness following costimulation-deficient Ag presentation.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Epítopos de Linfocito T/genética , Inmunoconjugados , Activación de Linfocitos/genética , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Abatacept , Adyuvantes Inmunológicos/farmacología , Adyuvantes Inmunológicos/fisiología , Animales , Anticuerpos Monoclonales/farmacología , Presentación de Antígeno/genética , Células Presentadoras de Antígenos/inmunología , Células Presentadoras de Antígenos/metabolismo , Antígenos CD/metabolismo , Antígenos CD/fisiología , Antígenos de Diferenciación/farmacología , Antígeno B7-1/metabolismo , Antígeno B7-1/fisiología , Antígeno B7-2 , Antígenos CD28/inmunología , Antígenos CD28/farmacología , Antígeno CTLA-4 , Células Cultivadas , Anergia Clonal/genética , Anergia Clonal/inmunología , Antígeno H-Y/inmunología , Fragmentos Fab de Inmunoglobulinas/farmacología , Inmunofenotipificación , Inmunosupresores/farmacología , Interleucina-2/farmacología , Activación de Linfocitos/inmunología , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Ratones Transgénicos , SolubilidadRESUMEN
Epitope spread has been proposed as a possible mechanism for diversification of the autoimmune T-cell response during disease. Specifically, it offers a plausible mechanism for the previously obscure cyclical nature of autoimmune demyelination whereby the sequence of attack, quiescence and reactivation may recur over a long period of time. However, we were concerned that previous studies of epitope spread have not necessarily shown it to be well correlated with disease severity or relapse. Furthermore, we had studied two transgenic models of exacerbated experimental allergic encephalomyelitis (EAE) in which no indication of spread away from the initial disease-inducing peptide could be observed. We conducted a systematic, longitudinal study in SJL mice to look for determinant spread during relapsing and remitting EAE, correlating epitope recognition and cytokine production with disease severity. When T cells from spleen, lymph node and central nervous system (CNS) were analysed, little or no determinant spread was found. The best immunological correlate of relapse was the reappearance after remission of CNS-infiltrating T cells mounting a strong proliferative and interferon (IFN)-gamma response to the original disease-inducing epitope. Our data do not support a general role for determinant spread in EAE relapse. Rather, they indicate the importance of a focused proliferative and IFN-gamma response to the disease-inducing peptide.
Asunto(s)
Encefalomielitis Autoinmune Experimental/inmunología , Epítopos , Animales , Sistema Nervioso Central/inmunología , Citocinas/biosíntesis , Encefalomielitis Autoinmune Experimental/etiología , Ratones , Periodicidad , Recurrencia , Bazo/inmunologíaRESUMEN
One of the most important omissions in recent evolutionary theory concerns how eukaryotes could emerge and evolve. According to the currently accepted views, the first eukaryotic cell possessed a nucleus, an endomembrane system, and a cytoskeleton but had an inefficient prokaryotic-like metabolism. In contrast, one of the most ancient eukaryotes, the metamonada Giardia lamblia, was found to have formerly possessed mitochondria. In sharp contrast with the traditional views, this paper suggests, based on the energetic aspect of genome organization, that the emergence of eukaryotes was promoted by the establishment of an efficient energy-converting organelle, such as the mitochondrion. Mitochondria were acquired by the endosymbiosis of ancient alpha-purple photosynthetic Gram-negative eubacteria that reorganized the prokaryotic metabolism of the archaebacterial-like ancestral host cells. The presence of an ATP pool in the cytoplasm provided by this cell organelle allowed a major increase in genome size. This evolutionary change, the remarkable increase both in genome size and complexity, explains the origin of the eukaryotic cell itself. The loss of cell wall and the appearance of multicellularity can also be explained by the acquisition of mitochondria. All bacteria use chemiosmotic mechanisms to harness energy; therefore the periplasm bounded by the cell wall is an essential part of prokaryotic cells. Following the establishment of mitochondria, the original plasma membrane-bound metabolism of prokaryotes, as well as the funcion of the periplasm providing a compartment for the formation of different ion gradients, has been transferred into the inner mitochondrial membrane and intermembrane space. After the loss of the essential function of periplasm, the bacterial cell wall could also be lost, which enabled the naked cells to establish direct connections among themselves. The relatively late emergence of mitochondria may be the reason why multicellularity evolved so slowly.
Asunto(s)
Evolución Biológica , Células Eucariotas/fisiología , Genoma Bacteriano , Modelos Biológicos , Células Procariotas/fisiología , Replicación del ADN , Metabolismo Energético , Escherichia coli/genética , Escherichia coli/crecimiento & desarrollo , Vectores Genéticos , Orgánulos/metabolismoRESUMEN
The progression of experimental allergic encephalomyelitis (EAE) in certain mouse strains has been reported to involve a broadening of the response to myelin antigens, apparently resulting from priming to endogenous determinants of the myelin sheath. The phenomenon has been termed determinant spread. Interest in this effect has centered on the mechanism it offers to explain the progressive, relapsing and remitting course of EAE and indeed of multiple sclerosis. We have conducted a systematic, longitudinal study in SJL mice to look for determinant spread during relapsing and remitting EAE, correlating epitope recognition and cytokine production with disease severity. Disease was induced using three of the four encephalitogenic proteolipid protein or myelin basic protein epitopes, and responses to each of four epitopes recognized by SJL T cells were tracked through acute disease, remission and relapse. The responses of lymph node cells, splenocytes and central nervous system (CNS)-infiltrating T cells were analyzed. While marginal, transient responses to secondary epitopes were detectable in splenocytes, CNS-infiltrating cells showed a dominant response to the original disease-inducing epitope without evidence of a shift to other determinants during relapse. Disease relapse was correlated with an increase in CNS-infiltrating cells and a high proliferative and interferon (IFN)-gamma response to the disease-inducing peptide. During remission, there was a decrease in numbers of cells infiltrating the CNS. These cells were down-regulated, showing low if any response to the myelin peptides tested as measured by proliferation, production of IFN-gamma or production of IL-4. Our findings argue strongly against a causal role for determinant spread in disease relapse as observed in these models of EAE.
Asunto(s)
Encefalomielitis Autoinmune Experimental/inmunología , Epítopos Inmunodominantes/inmunología , Proteína Básica de Mielina/inmunología , Proteína Proteolipídica de la Mielina/inmunología , Fragmentos de Péptidos/inmunología , Secuencia de Aminoácidos , Animales , Encéfalo/inmunología , Encéfalo/metabolismo , Movimiento Celular/inmunología , Citocinas/biosíntesis , Modelos Animales de Enfermedad , Encefalomielitis Autoinmune Experimental/etiología , Encefalomielitis Autoinmune Experimental/patología , Femenino , Epítopos Inmunodominantes/análisis , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/patología , Ratones , Ratones Endogámicos , Datos de Secuencia Molecular , Recurrencia , Médula Espinal/inmunología , Médula Espinal/metabolismo , Bazo/inmunología , Bazo/patología , Linfocitos T/inmunología , Linfocitos T/metabolismo , Factores de TiempoRESUMEN
Splenectomy is known to increase the risk of Overwhelming Postsplenectomy Infection (OPSI). Autotransplantation is one of the possibilities to preserve splenic functions. The authors performed spleen autotransplantations in two cases after the splenectomy of cystigerous spleens. Ten pieces from the intact spleens each sized 10 x 20 x 2 mm were implanted in between the plates of the great omentum according to Furka's spleen apron method. The function of the reimplanted splenic tissue was demonstrated by scintigraphic investigations.
Asunto(s)
Quistes/cirugía , Bazo/trasplante , Esplenectomía , Enfermedades del Bazo/cirugía , Adulto , Infecciones Bacterianas , Quistes/etiología , Quistes/parasitología , Estudios de Seguimiento , Humanos , Laparotomía/métodos , Región Lumbosacra/lesiones , Masculino , Epiplón/cirugía , Cintigrafía , Factores de Riesgo , Bazo/diagnóstico por imagen , Esplenectomía/efectos adversos , Enfermedades del Bazo/etiología , Enfermedades del Bazo/parasitología , Rotura del Bazo/etiología , Rotura del Bazo/cirugía , Trasplante Autólogo , Heridas no Penetrantes/complicacionesRESUMEN
In 8 of 1009 patients receiving renal grafts and consecutive immunosuppressive therapy during the last 20 years in Budapest, Hungary, Kaposi's sarcoma developed 6.5 months (average) after transplantation. Of 8 cutaneous cases of this disease, 5 also presented visceral manifestations. Seven patients died. Those with visceral tumors died because of the tumor itself. One patient affected by cutaneous tumor has survived for 5 years post-treatment. The relatively high incidence of Kaposi's sarcoma may be explained by a high infection rate with Herpes virus 8, which was shown to be positive in all three cases investigated.
Asunto(s)
Herpesvirus Humano 8/aislamiento & purificación , Trasplante de Riñón/efectos adversos , Sarcoma de Kaposi/patología , Adulto , Autorradiografía , Southern Blotting , Femenino , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/virología , Neoplasias Pulmonares/etiología , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/virología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Estudios Retrospectivos , Sarcoma de Kaposi/etiología , Sarcoma de Kaposi/virología , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/virología , Neoplasias Gástricas/etiología , Neoplasias Gástricas/patología , Neoplasias Gástricas/virologíaRESUMEN
A pathogenic role for self-reactive cells against the stress protein Hsp60 has been proposed as one of the events leading to autoimmune destruction of pancreatic beta cells in the diabetes of nonobese diabetic (NOD) mice. To examine this hypothesis, we generated transgenic NOD mice carrying a murine Hsp60 transgene driven by the H-2E alpha class II promoter. This would be expected to direct expression of the transgene to antigen-presenting cells including those in the thymus and so induce immunological tolerance by deletion. Detailed analysis of Hsp60 expression revealed that the endogenous gene is itself expressed strongly in thymic medullary epithelium (and weakly in cortex) yet fails to induce tolerance. Transgenic mice with retargeted Hsp60 showed overexpression of the gene in thymic cortical epithelium and in bone marrow-derived cells. Analysis of spontaneous T-cell responses to a panel of self and heterologous Hsp60 antigens showed that tolerance to the protein had not been induced, although responses to an immunodominant 437-460 epitope implicated in disease were suppressed, probably indicating an epitope shift. This correlated with changes in disease susceptibility: insulitis in transgenic mice was substantially reduced so that pathology rarely progressed beyond periislet infiltration. This was reflected in a substantial reduction in hyperglycemia and disease. These data indicate that T cells specific for some epitopes of murine Hsp60 are likely to be involved in the islet-cell destruction that occurs in NOD mice.
Asunto(s)
Chaperonina 60/biosíntesis , Chaperonina 60/inmunología , Diabetes Mellitus Tipo 1/inmunología , Islotes Pancreáticos/inmunología , Activación de Linfocitos , Linfocitos T/inmunología , Animales , Diabetes Mellitus Tipo 1/genética , Susceptibilidad a Enfermedades , Femenino , Genes MHC Clase II , Inmunidad Celular , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Ratones Endogámicos NOD , Ratones Transgénicos , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/inmunología , Timo/inmunologíaRESUMEN
Major histocompatibility complex (MHC) class II genes are the strongest susceptibility markers for many human autoimmune diseases. A perplexing aspect of this is that HLA alleles can confer either susceptibility or dominant protection. In nonobese diabetic (NOD) mice, the strongest known diabetes susceptibility locus is within the MHC and is presumed to be the H-2Ag7 product. When NOD mice carry a transgenic E alpha d molecule allowing expression of an H-2E heterodimer, diabetes is prevented. We investigated whether, as in human autoimmunity, a single class II heterodimer might protect from some autoimmune diseases while predisposing to others. NOD mice are susceptible to experimental autoimmune encephalomyelitis (EAE) induced by the proteolipoprotein (PLP) epitope 56-70. Susceptibility to EAE was analyzed in NOD mice which either have or lack transgenic H-2E expression. We found that H-2E expression in NOD mice has converse effects on diabetes and EAE: while diabetes is prevented, EAE is greatly exacerbated and leads to demyelination. Although PLP 56-70 could be presented both in the context of H-2A and H-2E, increased disease severity in H-2E transgenic mice could not be attributed either to an enhanced T cell proliferative response to PLP or to differences in determinant spread. However, cytokine analysis of the response revealed important differences between NOD mice and their H-2E transgenic counterparts: H-2E expression was associated with reduced interleukin-4 secretion and enhanced interferon-gamma (IFN-gamma) secretion by lymph node cells, while the response of central nervous system infiltrating T cells displayed a markedly enhanced IFN-gamma response. Thus, whether a particular class II molecule confers resistance or susceptibility to an autoimmune disease may depend on differential cytokine profiles elicited by particular class II/autoantigen complexes.
Asunto(s)
Citocinas/biosíntesis , Diabetes Mellitus Tipo 1/prevención & control , Encefalomielitis Autoinmune Experimental/patología , Antígenos H-2/genética , Células TH1/metabolismo , Secuencia de Aminoácidos , Animales , Diabetes Mellitus Tipo 1/genética , Encefalomielitis Autoinmune Experimental/genética , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos NOD , Ratones Transgénicos , Datos de Secuencia Molecular , Proteína Proteolipídica de la Mielina/genética , Proteína Proteolipídica de la Mielina/inmunologíaRESUMEN
The initial report of T cell receptor (TCR) V beta-specific thymic selection in mice showed association with expression of H-2E molecules and affected V beta 17a T cells which were present in CD4+8+ double positive thymocytes but deleted from the CD4+ and CD8+ single positive populations. Similar deletions were subsequently reported for V beta 8.1+ and V beta 6+ T cells in Mls-1a mouse strains and for V beta 3+ T cells in Mls-2a/3a strains. The 'Mls antigens' are most effectively presented by H-2E molecules but certain alleles of H-2A molecules can also present these endogenous superantigens. Expression of Mls antigens can cause both V beta-specific thymic deletion and stimulation of peripheral T cells from Mls-negative strains. Another category of 'Mls-like' antigens cause only V beta-specific thymic deletion in H-2E+ strains, affecting V beta 5+ and V beta 11+ T cells. The non-MHC ligands responsible for each of these effects are superantigens analogous to the exogenous bacterial superantigens, which also show TCR V beta-specific stimulatory effects when presented by MHC class II positive antigen-presenting cells. The genes encoding endogenous superantigens in mice were shown to co-segregate with mouse mammary tumour virus integrations (Mtv) and to be the Mtv-LTR orf genes. In vitro translation of Mtv-LTR orf genes identified their products as type II integral membrane glycoproteins with the polymorphic C terminus outside the cell. These polymorphisms correlate with specificity for the different TCR V beta chains. Virtually all TCR V beta-specific negative selection in the mouse thymus can be accounted for by the expression of Mtv or MMTV (the infectious counterparts of Mtv proviral integrants) LTR-orf proteins, presented with H-2E or certain H-2A alleles. It is unlikely that TCR V beta-specific positive selection is due to endogenous superantigens since it does not segregate with Mtv genomes. In humans, HLA-DR molecules appear to be homologous with H-2E in mice whereas HLA-DQ are the homologues of H-2A. H-2E negative mice transgenic for HLA-DR alpha chain express a mouse/human heterodimeric molecule which presents Mtv superantigens causing TCR V beta-specific deletion. Such trans-species class II molecules are also effective in TCR V beta-specific positive selection of V beta 2+, V beta 6+ and V beta 10+ T cells. Taken together, these results show that human MHC class II molecules can interact with the murine T cell repertoire.(ABSTRACT TRUNCATED AT 400 WORDS)
Asunto(s)
Presentación de Antígeno/inmunología , Genes MHC Clase II/inmunología , Antígenos Estimulantes de Linfocito Menor/genética , Antígenos Estimulantes de Linfocito Menor/inmunología , Timo/inmunología , Animales , Humanos , Virus del Tumor Mamario del Ratón/inmunología , Ratones , Ratones Transgénicos , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Especificidad de la EspecieRESUMEN
The use of HLA transgenic mice in models of immunity and disease assumes that human MHC molecules are able to contribute toward the positive selection of the mouse TCR repertoire. As an initial step towards analysis of this we have compared the relative ability of DR alpha/E beta or E alpha/E beta complexes to induce T cell receptor (TCR) positive selection in H-2Ea and HLA-DRA transgenic mice lacking endogenous E alpha. The results show that, like E alpha/E beta, the hybrid DR alpha/E beta complexes are capable of mediating positive selection of V beta 2+, V beta 6+, and V beta 10+ cells. However, differences were found between the effects of the two transgenes. Thus, while V beta 6+ cells were efficiently selected in both H-2Ea and DRA transgenic mice, positive selection of V beta 10+ cells was less apparent in the DRA transgenic mice. Variation between Ea and DRA transgenic mice is consistent with the notion that this process is dependent on differential binding of endogenous peptides to the E alpha/E beta and DR alpha/E beta complexes. Furthermore, contrary to expectations, in neither set of mice was positive selection limited solely to the CD4+ subset. Thus, examples were found in which V beta-specific positive selection was confined to either the CD4+ or CD8+ subsets, and others in which both subpopulations were concomitantly increased. In the case of V beta 2 positive selection, H-2Ea transgenic mice showed expansion of these cells in both the CD4+ and CD8+ subpopulations while in DRA transgenic mice this occurred predominantly in the CD8+ subpopulation.
Asunto(s)
Antígenos H-2/genética , Antígenos HLA-DR/genética , Receptores de Antígenos de Linfocitos T alfa-beta/fisiología , Linfocitos T/inmunología , Animales , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones TransgénicosRESUMEN
Products of specific mouse Mtv genes expressed in association with mouse MHC class II products cause the deletion of T cells expressing particular TCR V beta gene segments. These endogenous deletion ligands have been termed superantigens due to their ability to negatively select entire T-cell families, as defined by V beta-chain usage. In most cases, deletion is preferentially effected through interaction of the Mtv ligand with H-2E products. Although human DR alpha shares only 75% identity with the E alpha chain of H-2E, it has previously been shown to substitute for the mouse homologue in its capacity to induce the deletion of V beta 11- and V beta 17a-bearing T cells. In the present study, we have undertaken a more comprehensive analysis of the interaction of mixed DR alpha/E beta pairs with various endogenous Mtv integrants in various mouse backgrounds, leading to negative selection of particular V beta families. We show in this paper that transgenic DR alpha/E beta can also efficiently interact with products of Mtv-7, causing deletion of both V beta 6+ and V beta 7+ cells. Deletion of V beta 11+ T cells in DRA transgenic mice carrying Mtv-8 and -9, however, was less efficient than in control H-2Ea transgenic mice. These data and those from other MHC transgenic mouse studies show that while the class II alpha chain can influence the interaction with superantigen, it is the identity of the beta chain that seems to be critical.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Supresión Clonal , Antígenos HLA-DR/genética , Virus del Tumor Mamario del Ratón/genética , Receptores de Antígenos de Linfocitos T alfa-beta/análisis , Animales , Femenino , Cadenas alfa de HLA-DR , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Ratones Transgénicos , ARN Mensajero/análisis , Superantígenos/genéticaRESUMEN
The authors report their own longtime experience with the incidence of pediatric otitis with allergic etiology. They conclude that pediatric otitis, especially the secretory type, is not always curable by the common conservative antibiotic therapy because in many cases the primary cause of the disease is not the infection but allergy. The infection in such cases is a secondary, accompanying complication. The suggestion has been supported by the statistical data. Moreover reviewed are the diagnostic methods and therapy they have applied.
Asunto(s)
Hipersensibilidad/complicaciones , Otitis Media/etiología , Adolescente , Niño , Preescolar , Humanos , Hipersensibilidad/epidemiología , Incidencia , Lactante , Otitis Media/epidemiología , Yugoslavia/epidemiologíaRESUMEN
Selegiline is prepared in a three-step synthesis starting from phenylacetone and methylamine. Its possible impurities may be the (+)-isomer and compounds formed in side reactions. The syntheses of selegiline's metabolites are also described.
Asunto(s)
Selegilina/síntesis química , Selegilina/metabolismoRESUMEN
MS rarely occurs in gypsies in Hungary despite the high DR2 frequency. When it does occur, it has special features more resembling that of Asians than Central Europeans. In order to find correlation between the clinical observations and the immunogenetical data, the distribution of DQw1 subtypes was investigated by means of Eco RV - DQ beta RFLP in DR2 positive healthy gypsies and Hungarians, as well asin DR2-positive Hungarian and unselected gypsy MS patients. DQw6 correlated with MS susceptibility in Hungarians. This allotype was completely absent in healthy DR2-positive gypsies. DR2-positive gypsy MS patients, however, carried DQw6. No correlation of complement allotypes with the occurrence of MS was found in Hungarians, while a striking elevation of C4 Q0 occurred in gypsy MS patients compared with healthy individuals in the gypsy group. The absence of the DR2, DW2, DQw6 haplotype, and the frequency of C4A Q0 in healthy gypsies seems to be associated with the low MS prevalence, but genes outside this region might also influence the MS susceptibility.
Asunto(s)
Esclerosis Múltiple/etnología , Romaní , Alelos , Complemento C4a/análisis , Complemento C4a/genética , Complemento C4b/análisis , Femenino , Antígenos HLA-B/análisis , Antígenos HLA-B/genética , Antígeno HLA-B7/genética , Antígenos HLA-DQ/análisis , Antígenos HLA-DQ/genética , Antígeno HLA-DR2/análisis , Humanos , Hungría/epidemiología , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/genética , Esclerosis Múltiple/inmunología , Polimorfismo de Longitud del Fragmento de RestricciónRESUMEN
A series of new phenoxypropanolamines with cyclic guanidine and isothiourea moieties has been prepared and investigated for non-specific beta- and alpha-adrenoreceptor activity by receptor binding experiments on crude rat brain membrane. Some of them [9a, 10c] possess affinity for both beta- and alpha-adrenoreceptors.