RESUMEN
High throughput sequencing technologies have revolutionized the potential to reconcile incongruence between gene and species trees, and numerous approaches have been developed to take advantage of these advances. Genotyping-by-sequencing is becoming a regular tool for gathering phylogenetic data, yet comprehensive evaluations of phylogenetic methods using these data are sparse. Here we use multiple phylogenetic and population genetic methods for genotyping-by-sequencing data to assess species relationships in a group of forest insect pests, the spruce budworm (Choristoneura fumiferana) species complex. With few exceptions, all methods agree on the same relationships, most notably placing C. pinus as basal to the remainder of the group, rather than C. fumiferana as previously suggested. We found strong support for the monophyly of C. pinus, C. fumiferana, and C. retiniana, but more ambiguous relationships and signatures of introgression in a clade of western lineages, including C. carnana, C. lambertiana, C. occidentalis occidentalis, C. occidentalis biennis, and C. orae. This represents the most taxonomically comprehensive genomic treatment of the spruce budworm species group, which is further supported by the broad agreement among multiple methodologies.
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Genoma de los Insectos , Mariposas Nocturnas/genética , Filogenia , Polimorfismo de Nucleótido Simple/genética , Animales , Análisis Discriminante , Especiación Genética , Genética de Población , Genotipo , Geografía , América del Norte , Análisis de Componente Principal , Análisis de Secuencia de ADN , Especificidad de la Especie , Estados UnidosRESUMEN
As global climate patterns continue to change and extreme weather events become increasingly common, it is likely that many ecological interactions will be affected. One such interaction is the multipartite symbiosis that exists between the mountain pine beetle and two species of fungi, Grosmannia clavigera and Ophiostoma montium. In this mutualism, the fungi provide nutrition to the beetle, while the fungi benefit by being dispersed to new host trees. Multi-partite mutualisms are predicted to be unstable due to strong direct competition among symbionts or natural selection for superior over inferior mutualists. However, this mutualism has remained stable over long periods of evolutionary time. In this paper, we developed a temperature-based model for the spread of fungi within a tree and connected it to an existing model for mountain pine beetle development. Using this integrated model for fungal growth, we explored the possibility that temperature variability is a stabilizing mechanism for the mountain pine beetle-fungi mutualism. Of the three types of temperature variability we tested: intra-year, inter-year and variability due to transitioning between different thermal habitats (thermal migration), we found that thermal migration was the most robust stabilizing mechanism. Additionally, we found that the MPB attack density or spacing between fungal lesions also had a significant effect on the stability of the system. High attack densities or close lesion spacings also tended to stabilize the system, regardless of temperature.
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Escarabajos/fisiología , Modelos Biológicos , Ophiostoma/fisiología , Simbiosis/fisiología , Temperatura , AnimalesRESUMEN
Pattern formation occurs in a wide range of biological systems. This pattern formation can occur in mathematical models because of diffusion-driven instability or due to the interaction between reaction, diffusion, and chemotaxis. In this paper, we investigate the spatial pattern formation of attack clusters in a system for Mountain Pine Beetle. The pattern formation (aggregation) of the Mountain Pine Beetle in order to attack susceptible trees is crucial for their survival and reproduction. We use a reaction-diffusion equation with chemotaxis to model the interaction between Mountain Pine Beetle, Mountain Pine Beetle pheromones, and susceptible trees. Mathematical analysis is utilized to discover the spacing in-between beetle attacks on the susceptible landscape. The model predictions are verified by analysing aerial detection survey data of Mountain Pine Beetle Attack from the Sawtooth National Recreation Area. We find that the distance between Mountain Pine Beetle attack clusters predicted by our model closely corresponds to the observed attack data in the Sawtooth National Recreation Area. These results clarify the spatial mechanisms controlling the transition from incipient to epidemic populations and may lead to control measures which protect forests from Mountain Pine Beetle outbreak.
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Escarabajos/fisiología , Escarabajos/patogenicidad , Modelos Biológicos , Pinus/parasitología , Animales , Biología Computacional , Ecosistema , Idaho , Modelos Lineales , Conceptos Matemáticos , Reconocimiento de Normas Patrones Automatizadas/estadística & datos numéricos , Feromonas/fisiología , Enfermedades de las Plantas/parasitología , Enfermedades de las Plantas/estadística & datos numéricosRESUMEN
The study of nanomaterials is an active area of research for technological applications as well as fundamental science. A common method for studying properties of isolated nanoparticles is by an in-vacuum particle beam produced via an aerodynamic lens. Despite being common practice, characterization of such beams has proven difficult as light scattering detection techniques fail for particles with sizes beyond the diffraction limit. Here we present a new technique for characterizing such nanoparticle beams using strong field ionization. By focusing an ultrafast, mJ-level laser into the particle beam, a nanoparticle within the laser focus is ionized and easily detected by its ejected electrons. This method grants direct access to the nanoparticle density at the location of the focus, and by scanning the focus through the transverse and longitudinal profiles of the particle beam we attain the 3-dimensional particle density distribution for a cylindrically symmetric beam. Further, we show that strong field ionization is effective in detecting spherical nanoparticles as small as 10 nm in diameter. Additionally, this technique is an effective tool in optimizing the particle beam for specific applications. As an example we show that the particle beam density and width can be manipulated by restricting the gas flow into the aerodynamic lens.
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Temperature is the most significant factor controlling developmental timing of most temperate poikilotherms. In the face of climate change, a crucial question is how will poikilothermic organisms evolve when faced with changing thermal environments? In this paper, we integrate models for developmental timing and quantitative genetics. A simple model for determining developmental milestones (emergence times, egg hatch) is introduced, and the general quantitative genetic recursion for the mean value of developmental parameters presented. Evolutionary steps proportional to the difference between current median parameters and parameters currently selected for depend on the fitness, which is assumed to depend on emergence density. Asymptotic states of the joint model are determined, which turn out to be neutrally stable (marginal) fixed points in the developmental model by itself, and an associated stable emergence distribution is also described. An asymptotic convergence analysis is presented for idealized circumstances, indicating basic stability criteria. Numerical studies show that the stability analysis is quite conservative, with basins of attraction to the asymptotic states that are much larger than expected. It is shown that frequency-dependent selection drives oscillatory dynamics and that the asymptotic states balance the asymmetry of the emergence distribution and the fitness function.
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Evolución Biológica , Cambio Climático , Estadios del Ciclo de Vida/fisiología , Modelos Genéticos , Temperatura , Adaptación Biológica/fisiología , Algoritmos , Animales , Simulación por Computador , Ambiente , Extinción Biológica , Fertilidad/fisiología , Aptitud Genética/fisiología , Variación Genética/fisiología , Insectos/genética , Insectos/crecimiento & desarrollo , Fenotipo , Carácter Cuantitativo Heredable , Reproducción/fisiología , Estaciones del Año , Selección Genética/fisiología , Distribuciones EstadísticasRESUMEN
Muscular dysgenesis (mdg/mdg), a mutation of the skeletal muscle dihydropyridine receptor (DHPR) alpha 1 subunit, has served as a model to study the functions of the DHPR in excitation-contraction coupling and its role in triad formation. We have investigated the question of whether the lack of the DHPR in dysgenic skeletal muscle results in a failure of triad formation, using cell lines (GLT and NLT) derived from dysgenic (mdg/mdg) and normal (+/+) muscle, respectively. The lines were generated by transfection of myoblasts with a plasmid encoding a Large T antigen. Both cell lines express muscle-specific proteins and begin organization of sarcomeres as demonstrated by immunocytochemistry. Similar to primary cultures, dysgenic (GLT) myoblasts show a higher incidence of cell fusion than their normal counterparts (NLT). NLT myotubes develop spontaneous contractile activity, and fluorescent Ca2+ recordings show Ca2+ release in response to depolarization. In contrast, GLTs show neither spontaneous nor depolarization-induced Ca2+ transients, but do release Ca2+ from the sarcoplasmic reticulum (SR) in response to caffeine. Despite normal transverse tubule (T-tubule) formation, GLT myotubes lack the alpha 1 subunit of the skeletal muscle DHPR, and the alpha 2 subunit is mistargeted. Nevertheless, the ryanodine receptor (RyR) frequently develops its normal, clustered organization in the absence of both DHPR alpha subunits in the T-tubules. In EM, these RyR clusters correspond to T-tubule/SR junctions with regularly spaced feet. These findings provide conclusive evidence that interactions between the DHPR and RyR are not involved in the formation of triad junctions or in the normal organization of the RyR in the junctional SR.
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Canales de Calcio/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Animales , Canales de Calcio/genética , Canales de Calcio Tipo L , Línea Celular , Fusión de Membrana , Proteínas Musculares/genética , Músculo Esquelético/citología , Músculo Esquelético/ultraestructura , Ratas , Canal Liberador de Calcio Receptor de RianodinaRESUMEN
We have studied the subcellular distribution of the alpha 1 and alpha 2 subunits of the skeletal muscle dihydropyridine (DHP) receptor with immunofluorescence labeling of normal and dysgenic (mdg) muscle in culture. In normal myotubes both alpha subunits were localized in clusters associated with the T-tubule membranes of longitudinally as well as transversely oriented T-tubules. The DHP receptor-rich domains may represent the sites where triad junctions with the sarcoplasmic reticulum are being formed. In cultures from dysgenic muscle the alpha 1 subunit was undetectable and the distribution patterns of the alpha 2 subunit were abnormal. The alpha subunit did not form clusters nor was it discretely localized in the T-tubule system. Instead, alpha 2 was found diffusely distributed in parts of the T-system, in structures in the perinuclear region and in the plasma membrane. These results suggest that an interaction between the two alpha subunits is required for the normal distribution of the alpha 2 subunit in the T-tubule membranes. Spontaneous fusion of normal non-muscle cells with dysgenic myotubes resulted in a regional expression of the alpha 1 polypeptide near the foreign nuclei, thus defining the nuclear domain of a T-tubule membrane protein in multi-nucleated muscle cells. Furthermore, the normal intracellular distribution of the alpha 2 polypeptide was restored in domains containing a foreign "rescue" nucleus; this supports the idea that direct interactions between the DHP receptor alpha 1 and alpha 2 subunits are involved in the organization of the junctional T-tubule membranes.
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Músculos/metabolismo , Receptores Nicotínicos/metabolismo , Animales , Animales Recién Nacidos , Anticuerpos Monoclonales , Especificidad de Anticuerpos , Canales de Calcio , Células Cultivadas , Técnica del Anticuerpo Fluorescente , Ratones , Músculos/citología , Músculos/embriología , Ratas , Ratas Endogámicas , Receptores Nicotínicos/químicaRESUMEN
Excitation-contraction (E-C) coupling is thought to involve close interactions between the calcium release channel (ryanodine receptor; RyR) of the sarcoplasmic reticulum (SR) and the dihydropyridine receptor (DHPR) alpha 1 subunit in the T-tubule membrane. Triadin, a 95-kD protein isolated from heavy SR, binds both the RyR and DHPR and may thus participate in E-C coupling or in interactions responsible for the formation of SR/T-tubule junctions. Immunofluorescence labeling of normal mouse myotubes shows that the RyR and triadin co-aggregate with the DHPR in punctate clusters upon formation of functional junctions. Dysgenic myotubes with a deficiency in the alpha 1 subunit of the DHPR show reduced expression and clustering of RyR and triadin; however, both proteins are still capable of forming clusters and attaining mature cross-striated distributions. Thus, the molecular organization of the RyR and triadin in the terminal cisternae of SR as well as its association with the T-tubules are independent of interactions with the DHPR alpha 1 subunit. Analysis of calcium transients in dysgenic myotubes with fluorescent calcium indicators reveals spontaneous and caffeine-induced calcium release from intracellular stores similar to those of normal muscle; however, depolarization-induced calcium release is absent. Thus, characteristic calcium release properties of the RyR do not require interactions with the DHPR; neither do they require the normal organization of the RyR in the terminal SR cisternae. In hybrids of dysgenic myotubes fused with normal cells, both action potential-induced calcium transients and the normal clustered organization of the RyR are restored in regions expressing the DHPR alpha 1 subunit.
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Canales de Calcio/metabolismo , Calcio/metabolismo , Proteínas Portadoras , Microtúbulos/metabolismo , Proteínas Musculares/metabolismo , Músculos/metabolismo , Retículo Sarcoplasmático/metabolismo , Secuencia de Aminoácidos , Animales , Canales de Calcio/aislamiento & purificación , Canales de Calcio Tipo L , ATPasas Transportadoras de Calcio/aislamiento & purificación , ATPasas Transportadoras de Calcio/metabolismo , Células Cultivadas , Técnica del Anticuerpo Fluorescente , Péptidos y Proteínas de Señalización Intracelular , Sustancias Macromoleculares , Ratones , Ratones Mutantes , Microscopía Fluorescente , Microscopía de Contraste de Fase , Datos de Secuencia Molecular , Proteínas Musculares/aislamiento & purificación , Músculos/citología , Músculos/embriología , Ratas , Ratas Sprague-Dawley , Canal Liberador de Calcio Receptor de Rianodina , Retículo Sarcoplasmático/ultraestructuraRESUMEN
Muscular dysgenesis (mdg) in mice causes the failure of excitation-contraction (E-C) coupling in skeletal muscle. Cultured dysgenic muscle fails to contract upon depolarization, lacks typical muscle ultrastructure, including normal triads, and lacks functional voltage-dependent slow calcium channels. We show that normal rodent fibroblasts and 3T3 fibroblasts "rescue" dysgenic myotubes, reestablishing contractions (i.e., E-C coupling), normal ultrastructure, and functional slow calcium channels. These results support the finding that the expression of the slow calcium channel is affected in the mdg mutation and that this protein is essential for E-C coupling. Additionally, fibroblast rescue provides a system for examining the mechanisms of heterotypic cellular influence on cell function.
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Fibroblastos/fisiología , Contracción Muscular , Distrofia Muscular Animal/patología , Potenciales de Acción , Animales , Canales de Calcio/fisiología , Comunicación Celular , Células Cultivadas , Ratones , Ratones Mutantes , Feocromocitoma/patología , Ratas , Sarcómeros/ultraestructura , Médula Espinal/citología , Células Tumorales Cultivadas/fisiologíaRESUMEN
A murine monoclonal antibody (15H6) against the trichothecene mycotoxin T-2 was capable of neutralizing the in vitro protein synthesis inhibitory effect of T-2 toxin in human B lymphoblastoid cultures. It was further shown that 15H6 given to rats (250 mg/kg) 30 min before or 15 min after a lethal dose (1 mg/kg) of T-2 toxin conferred 100% survival. A lower dose of 15H6 (125 mg/kg), given 15 min after the lethal dose of T-2 toxin, protected 25% of the rats. An increased time to death and 45% survival was seen in rats given the full dose of 15H6 antibody 60 min after lethal toxin. These data are the first demonstration of effective prophylaxis and therapy for T-2 toxemia.
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Anticuerpos Monoclonales/uso terapéutico , Antitoxinas/uso terapéutico , Sesquiterpenos/antagonistas & inhibidores , Sesquiterpenos/inmunología , Toxina T-2/inmunología , Tricotecenos/antagonistas & inhibidores , Animales , Presión Sanguínea/efectos de los fármacos , Células Cultivadas , Frecuencia Cardíaca/efectos de los fármacos , Pruebas de Neutralización , Biosíntesis de Proteínas , Ratas , Toxina T-2/toxicidad , Tricotecenos/inmunologíaRESUMEN
CIB1 (calcium and integrin binding protein 1) is a small intracellular protein with numerous interacting partners, and hence has been implicated in various cellular functions. Recent studies have revealed emerging roles of CIB1 in regulating cancer cell survival and angiogenesis, although the mechanisms involved have remained largely undefined. In investigating the oncogenic function of CIB1, we initially found that CIB1 is widely up-regulated across a diverse range of cancers, with this upregulation frequently correlating with oncogenic mutations of KRas. Consistent with this, we found that ectopic expression of oncogenic KRas and HRas in cells resulted in elevated CIB1 expression. We previously described the Ca2+-myristoyl switch function of CIB1, and its ability to facilitate agonist-induced plasma membrane localisation of sphingosine kinase 1 (SK1), a location where SK1 is known to elicit oncogenic signalling. Thus, we examined the role this may play in oncogenesis. Consistent with these findings, we demonstrated here that over-expression of CIB1 by itself is sufficient to drive localisation of SK1 to the plasma membrane and enhance the membrane-associated enzymatic activity of SK1, as well as its oncogenic signalling. We subsequently demonstrated that elevated levels of CIB1 resulted in full neoplastic transformation, in a manner dependent on SK1. In agreement with our previous findings that SK1 is a downstream mediator of oncogenic signalling by Ras, we found that targeting CIB1 also inhibited neoplastic growth of cells induced by oncogenic Ras, suggesting an important pro-tumorigenic role for CIB1. Thus, we have demonstrated for the first time a role for CIB1 in neoplastic transformation, and revealed a novel mechanism facilitating oncogenic signalling by Ras and SK1.
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Proteínas de Unión al Calcio/genética , Neoplasias/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Calcio/metabolismo , Carcinogénesis/genética , Línea Celular Tumoral , Membrana Celular/genética , Supervivencia Celular , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Neoplasias/patología , Proteínas Proto-Oncogénicas p21(ras)/biosíntesisRESUMEN
Loss of heterozygosity (LOH) at the long arm of chromosome 16 occurs in at least half of all breast tumors and is considered to target one or more tumor suppressor genes. Despite extensive studies by us and by others, a clear consensus of the boundaries of the smallest region of overlap (SRO) could not be identified. To find more solid evidence for SROs, we tested a large series of 712 breast tumors for LOH at 16q using a dense map of polymorphic markers. Strict criteria for LOH and retention were applied, and results that did not meet these criteria were excluded from the analysis. We compared LOH results obtained from samples with different DNA isolation methods, ie., from microdissected tissue versus total tissue blocks. In the latter group, 16% of the cases were excluded because of noninterpretable LOH results. The selection of polymorphic markers is clearly influencing the LOH pattern because a chromosomal region seems more frequently involved in LOH when many markers from this region are used. The LOH detection method, i.e., radioactive versus fluorescence detection, has no marked effect on the results. Increasing the threshold window for retention of heterozygosity resulted in significantly more cases with complex LOH, i.e., several alternating regions of loss and retention, than seen in tumors with a small window for retention. Tumors with complex LOH do not provide evidence for clear-cut SROs that are repeatedly found in other samples. On disregarding these complex cases, we could identify three different SROs, two at band 16q24.3 and one at 16q22.1. In all three tumor series, we found cases with single LOH regions that designated the distal region at 16q24.3 and the region at 16q22.1. Comparing histological data on these tumors did not result in the identification of a particular subtype with LOH at 16q or a specific region involved in LOH. Only the rare mucinous tumors had no 16q LOH at all. Furthermore, a positive estrogen content is prevalent in tumors with 16q LOH, but not in tumors with LOH at 16q24.3 only.
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Neoplasias de la Mama/genética , Mapeo Cromosómico/métodos , Cromosomas Humanos Par 16 , Pérdida de Heterocigocidad , Neoplasias de la Mama/patología , Fluorescencia , Humanos , Radioisótopos de Fósforo , Reacción en Cadena de la Polimerasa/métodosRESUMEN
ABSTRACT A spatially explicit model describing saprophytic colonization of dead cyclamen leaf tissue by the plant-pathogenic fungus Botrytis cinerea and the saprophytic fungal antagonist Ulocladium atrum was constructed. Both fungi explore the leaf and utilize the resources it provides. Leaf tissue is represented by a two-dimensional grid of square grid cells. Fungal competition within grid cells is modeled using Lotka-Volterra equations. Spatial expansion into neighboring grid cells is assumed proportional to the mycelial density gradient between donor and receptor cell. Established fungal biomass is immobile. Radial growth rates of B. cinerea and U. atrum in dead cyclamen leaf tissue were measured to determine parameters describing the spatial dynamics of the fungi. At temperatures from 5 to 25 degrees C, B. cinerea colonies expanded twice as rapidly as U. atrum colonies. In practical biological control, the slower colonization of space by U. atrum thus needs to be compensated by a sufficiently dense and even distribution of conidia on the leaf. Simulation results confirm the importance of spatial expansion to the outcome of the competitive interaction between B. cinerea and U. atrum at leaf scale. A sensitivity analysis further emphasized the importance of a uniform high density cover of vital U. atrum conidia on target leaves.
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A critical review of the published literature investigating the Internet and consumer health information was undertaken in order to inform further research and policy. A qualitative, narrative method was used, consisting of a three-stage process of identification and collation, thematic coding, and critical analysis. This analysis identified five main themes in the research in this area: (1) the quality of online health information for consumers; (2) consumer use of the Internet for health information; (3) the effect of e-health on the practitioner-patient relationship; (4) virtual communities and online social support and (5) the electronic delivery of information-based interventions. Analysis of these themes revealed more about the concerns of health professionals than about the effect of the Internet on users. Much of the existing work has concentrated on quantifying characteristics of the Internet: for example, measuring the quality of online information, or describing the numbers of users in different health-care settings. There is a lack of qualitative research that explores how citizens are actually using the Internet for health care.
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Educación en Salud , Internet , Educación en Salud/normas , Relaciones Médico-Paciente , Apoyo Social , Telemedicina/métodos , Interfaz Usuario-ComputadorRESUMEN
Kinase inhibitors block proliferative signals in BCR-ABL1+ leukemic cells, but their capacity to induce apoptosis is poorly understood. Initial studies suggested that very brief exposure to kinase inhibitors was sufficient to induce apoptosis in chronic myeloid leukemia (CML) cells. However, flaws in this experimental model have subsequently been identified, leading to the conclusion that apoptosis only occurs with sustained low-level kinase inhibition. Thus, the minimum duration of complete kinase inhibition required to commit CML cells to death is unknown. Here we confirm that <1 h is insufficient to induce significant commitment to death in BCR-ABL1+ cell lines and in primary CD34+ progenitor cells, and establish that commitment to cell death only occurs if kinase inhibition is maintained for 4 h or more. Remarkably, signal transducer and activator of transcription 5 (STAT5) inhibition in combination with transient (<1 h) tyrosine kinase inhibitor (TKI) exposure proved lethal for CML progenitors, despite the reactivation of Bcr-Abl after 1 h. JAK kinase inhibition did not induce cell death in combination with transient TKI exposure. Thus, STAT5 appears to be a critical determinant of the time-dependent sensitivity of CML progenitor cells to TKI treatment in a Bcr-Abl-dependent, but JAK-independent, manner. We conclude that combining kinase inhibition with STAT5 inhibition represents a promising therapeutic approach in BCR-ABL1+ leukemias.
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Apoptosis/efectos de los fármacos , Janus Quinasa 2/antagonistas & inhibidores , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Inhibidores de Proteínas Quinasas/farmacología , Factor de Transcripción STAT5/antagonistas & inhibidores , Antígenos CD34/inmunología , Western Blotting , Genes abl , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/inmunologíaRESUMEN
An automated microassay was adapted to the sutdy of specific in vitro lymphocyte transformation to dinitrochlorobenzene (DNCB) erythrocyte complexes (DNCB-antigen). Studies of culture conditions indicated that in flat-bottomed microtiter culture plates, 0.2ml culturese containing 4x105 leukocytes and a total culture time of 4 or 5 days yeild satisfactory results for the relatively low responses seen with specific antigens such as DNCB-antigen. Culture were incubated for 3 hr with tritiated thymidine and harvested with the Multipe Automated Sample Harvester(MASH II). The effect of DNCB rechallenge on in vitro lymphocte transformation was stuided using this automated microassay. DNCB rechallenge boosted the in vitro response to DNON 25 TO 31 MM Hg; four patients (hypercapnic, group II) at a co2 from 54 to57 mm Hg. AH 8165 0.25 mg/kg (one quarter of the dose required for intubation) was given by rapid central venous injection. Haemodynamic responses were similar in the two groups; these were increase in heart rate ranging from 45 to 60 percent, increases in mean arterial pressure of 17-20 pre cent, and increases in cardiac output of 22-32 per cent. The intensity of neuromusclar blockade of the forearm muscles after AH 8165 was similar in the two groups, and there was no significant difference in recovery rates; roup I patients were 80 per cent recovered in 36.6 min, group II patinets in 47.3 min. It was concluded that the activity of AH 8165 was not influenced by moderate changes in respiratory acid-base status.
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Dermatitis por Contacto/inmunología , Dinitroclorobenceno/farmacología , Activación de Linfocitos/efectos de los fármacos , Linfocinas/biosíntesis , Nitrobencenos/farmacología , Piel/inmunología , Antígenos , Eritrocitos/inmunología , Humanos , Inmunidad Celular , Leucocitos/inmunología , Microquímica , Fenómenos Fisiológicos de la Piel , Timidina/metabolismo , Factores de TiempoRESUMEN
Dinitrochlorobenzene (DNCB) coupled to peripheral blood erythrocytes or leukocytes forms a particulate complex, DNCB-antigen. The addition of DNCB-antigen induced blastogenesis and DNA synthesis in leukocyte cultures from DNCB-sensitized human subjects and not in leukocyte cultures from nonsensitized controls. In general, sensitized subjects who displayed a higher degree of cutaneous reactivity to DNCB, as manifested by duration and intensity of dermatitis, also showed a greater blastogenic response to DNCB-antigen in vitro. This quantitative correlation, however, was not invariant. Certain soluble factor(s), or lymphokines are released following the addition of DNCB-antigen to leukocyte cultures prepared from some sensitive subjects who were rechallenged one or more times with DNCB. These lymphokines induce blastogenesis in secondary target leukocyte populations from nonsensitized subjects. Extended studies are presented which slow little or no lymphokine activity in peripheral blood leukocyte cultures during a primary immune response, despite high degrees of blastogenic activity in response to DNCB-antigen. Significant lymphokine activity was observed only following additional rechallenge with DNCB. Blastogenesis and skin reactivity specific for DNCB have been shown to develop at about the same time during a primary immune response. This, along with the quantitative correlation shown in this communication, suggests that both processes probably reflect thymic-dependent cellular immunity. The appearance of lymphokine activity following rechallenge with DNCB suggests that DNCB-induced lymphokines may represent an amplifying mechanism of the cellular immune response that involves recruitment of previously uncommitted lymphocytes.
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Dermatitis por Contacto/etiología , Activación de Linfocitos/efectos de los fármacos , Linfocinas , Nitrobencenos , Antígenos , Células Cultivadas , Cloro , Clorobencenos/inmunología , ADN/biosíntesis , Dermatitis por Contacto/inmunología , Humanos , Inmunidad Celular , Leucocitos/inmunología , Linfocinas/biosíntesis , Nitrobencenos/inmunología , Pruebas CutáneasRESUMEN
Psoriatic epidermis shows excessive cell proliferation, incomplete morphogenesis, and glycogen accumulation. These three features may result from coordinate misregulation by the previously reported abnormal lesional ratio of cyclic AMP/cyclic GMP. If so, it is possible that psoriasis might improve by topical application of an agent known to alter cellular levels of cyclic nucleotides. In the present study papaverine (3.0 x 10-4 m) produced a 210percent increase (.02 smaller than p smaller than .05) in epidermal cyclic AMP levels in vitro. Therefore, 1 percent papaverine cream (approximately 2.7 x 10-2m papaverine) was chosen to establish whether a cyclic AMP elevating agent could improve a soriatic lesion. A double-blind comparison of 1 percent papaverine cream versus cream alone was conducted on matched lesions in 45 patients. Of those patients showing differential improvement (i.e., only one lesion of the pair improved), 81 percent (p=0.011) of those showing a response in the center of the lesion and 77 percent (p=0.046) of those improving at the edge had applied papaverine. Although no attempts were made to develop a papaverine formulation with immediate therapeutic utility, the numerically significant papaverine results suggest future therapeutic developments.
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AMP Cíclico/metabolismo , Papaverina/farmacología , Piel/efectos de los fármacos , Animales , AMP Cíclico/análisis , Depresión Química , Humanos , Ratones , Papaverina/uso terapéutico , Psoriasis/tratamiento farmacológico , Psoriasis/metabolismo , Piel/metabolismoRESUMEN
Previously we demonstrated that domain 5 (D5) of high-molecular-weight kininogen (HK) inhibits neovascularization in the chicken chorioallantoic membrane (CAM) assay and further found that kallikrein cleaved HK (HKa) inhibited FGF2-and VEGF-induced neovascularization, and thus was antiangiogenic. In this study, we sought to demonstrate whether uncleaved HK stimulates neovascularization and thus is proangiogenic. The chick chorioallantoic membrane was used as an in ovo assay of angiogenesis. Low-molecular-weight kininogen stimulates angiogenesis, indicating that D5 is not involved. Bradykinin stimulates neovascularization equally to HK and LK and is likely to be responsible for the effect of HK. A murine monoclonal antibody to HK (C11C1) also recognizes a similar component in chicken plasma as detected by surface plasmon resonance. Angiogenesis induced by FGF2 and VEGF is inhibited by this monoclonal antibody and is a more potent inhibitor of neovascularization induced by VEGF than an integrin alphavbeta3 antibody (LM 609). Our postulate that C11C1 inhibits the stimulation of angiogenesis by HK was confirmed when either C11C1 or D5 completely inhibited angiogenesis in the CAM induced by HK. Growth of human fibrosarcoma (HT-1080) on the CAM was inhibited by GST-D5 and C11C1. These results indicate HK is proangiogenic probably by releasing bradykinin and that a monoclonal antibody directed to HK could serve as an antiangiogenic agent with a potential for inhibiting tumor angiogenesis and other angiogenesis-mediated disorders.
Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Anticuerpos Monoclonales/farmacología , Quininógeno de Alto Peso Molecular/antagonistas & inhibidores , Neovascularización Fisiológica/inmunología , Alantoides/irrigación sanguínea , Animales , Anticuerpos Monoclonales/inmunología , Bradiquinina/farmacología , Embrión de Pollo , Corion/irrigación sanguínea , Relación Dosis-Respuesta a Droga , Factores de Crecimiento Endotelial/farmacología , Factor 2 de Crecimiento de Fibroblastos/farmacología , Fibrosarcoma/metabolismo , Glutatión Transferasa/genética , Glutatión Transferasa/farmacología , Humanos , Péptidos y Proteínas de Señalización Intercelular/farmacología , Quininógeno de Alto Peso Molecular/inmunología , Quininógeno de Alto Peso Molecular/farmacología , Quininógeno de Bajo Peso Molecular/farmacología , Linfocinas/farmacología , Estructura Terciaria de Proteína , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/farmacología , Resonancia por Plasmón de Superficie , Células Tumorales Cultivadas , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial VascularRESUMEN
Parents' general knowledge of child development and the demographic factors associated with that knowledge were studied. A questionnaire was completed by 230 parents of patients from three quite different pediatric practices in the south-central United States. Chi square analysis was used as the major statistical technique. Results indicated that age, educational level, and income were associated with level of child development knowledge. Parents reported the sources and educational techniques that were most helpful to them in the past and present. The majority (81%) of the questions that parents wished to direct to pediatricians, given sufficient time, were concerned with psycho- social issues. It appears that the pediatric practice is a logical means of providing information to parents about their children's health concerns, both behavioral and physical. These results emphasize the importance of training pediatricians in behavioral issues and in improving their communication skills. The results are presented to help pediatricians select the anticipatory guidance and educational techniques that might be provided to parents through the pediatric practice.