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1.
Cereb Cortex ; 34(1)2024 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-38011099

RESUMEN

The hippocampus (HC) and the orbitofrontal cortex (OFC) jointly encode a map-like representation of a task space to guide behavior. It remains unclear how the OFC and HC interact in encoding this map-like representation, though previous studies indicated that both regions have different functions. We acquired the functional magnetic resonance imaging data under a social navigation task in which participants interacted with characters in a two-dimensional "social space." We calculate the social relationships between the participants and characters and used a drift-diffusion model to capture the inner process of social interaction. Then we used multivoxel pattern analysis to explore the brain-behavior relationship. We found that (i) both the HC and the OFC showed higher activations during the selective trial than the narrative trial; (ii) the neural pattern of the right HC was associated with evidence accumulation during social interaction, and the pattern of the right lateral OFC was associated with the social relationship; (iii) the neural pattern of the HC can decode the participants choices, while the neural pattern of the OFC can decode the task information about trials. The study provided evidence for distinct roles of the HC and the OFC in encoding different information when representing social space.


Asunto(s)
Lóbulo Frontal , Corteza Prefrontal , Humanos , Corteza Prefrontal/diagnóstico por imagen , Conducta de Elección , Hipocampo/diagnóstico por imagen , Imagen por Resonancia Magnética , Medio Social
2.
Phys Chem Chem Phys ; 26(23): 16765-16773, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38819261

RESUMEN

It is of great significance to search for new two-dimensional materials with excellent photocatalytic water splitting properties. Here, the AlOX (X = Cl, Br, or I) monolayers were constructed to explore their electronic and optical properties as a potential photocatalyst and mechanism of high photocatalytic activity by first principles calculations, for the first time. The results show that the AlOX (X = Cl, Br, or I) monolayers are all dynamically and thermodynamically stable. It is found that the AlOI monolayer exhibits visible optical absorption with a 538 nm absorption band edge, due to its direct band gap of 2.22 eV. Moreover, an appropriate band edge potential ensures its excellent reduction-oxidation (redox) ability. The asymmetry of crystals along different directions results in a noncoplanar HOMO and LUMO as well as an anisotropy effective mass and favors the separation of photogenerated carriers. These findings present the potential of the AlOX (X = Cl, Br, or I) monolayers as photocatalysts.

3.
Hum Brain Mapp ; 44(1): 131-141, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36066186

RESUMEN

Parahippocampal cortex (PHC) is a vital neural bases in spatial navigation. However, its functional role is still unclear. "Contextual hypothesis," which assumes that the PHC participates in processing the spatial association between the landmark and destination, provides a potential answer to the question. Nevertheless, the hypothesis was previously tested using the picture categorization task, which is indirectly related to spatial navigation. By now, study is still needed for testing the hypothesis with a navigation-related paradigm. In the current study, we tested the hypothesis by an fMRI experiment in which participants performed a distance estimation task in a virtual environment under three different conditions: landmark free (LF), stable landmark (SL), and ambiguous landmark (AL). By analyzing the behavioral data, we found that the presence of an SL improved the participants' performance in distance estimation. Comparing the brain activity in SL-versus-LF contrast as well as AL-versus-LF contrast, we found that the PHC was activated by the SL rather than by AL when encoding the distance. This indicates that the PHC is elicited by strongly associated context and encodes the landmark reference for distance perception. Furthermore, accessing the representational similarity with the activity of the PHC across conditions, we observed a high similarity within the same condition but low similarity between conditions. This result indicated that the PHC sustains the contextual information for discriminating between scenes. Our findings provided insights into the neural correlates of the landmark information processing from the perspective of contextual hypothesis.


Asunto(s)
Giro Parahipocampal , Navegación Espacial , Humanos , Giro Parahipocampal/diagnóstico por imagen , Corteza Cerebral , Cognición , Imagen por Resonancia Magnética , Mapeo Encefálico
4.
Hum Brain Mapp ; 44(9): 3744-3757, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37067072

RESUMEN

A cognitive map is an internal representation of the external world that guides flexible behavior in a complex environment. Cognitive map theory assumes that relationships between entities can be organized using Euclidean-based coordinates. Previous studies revealed that cognitive map theory can also be generalized to inferences about abstract spaces, such as social spaces. However, it is still unclear whether humans can construct a cognitive map by combining relational knowledge between discrete entities with multiple abstract dimensions in nonsocial spaces. Here we asked subjects to learn to navigate a novel object space defined by two feature dimensions, price and abstraction. The subjects first learned the rank relationships between objects in each feature dimension and then completed a transitive inferences task. We recorded brain activity using functional magnetic resonance imaging (fMRI) while they performed the transitive inference task. By analyzing the behavioral data, we found that the Euclidean distance between objects had a significant effect on response time (RT). The longer the one-dimensional rank distance and two-dimensional (2D) Euclidean distance between objects the shorter the RT. The task-fMRI data were analyzed using both univariate analysis and representational similarity analysis. We found that the hippocampus, entorhinal cortex, and medial orbitofrontal cortex were able to represent the Euclidean distance between objects in 2D space. Our findings suggest that relationship inferences between discrete objects can be made in a 2D nonsocial space and that the neural basis of this inference is related to cognitive maps.


Asunto(s)
Corteza Entorrinal , Hipocampo , Humanos , Hipocampo/fisiología , Aprendizaje/fisiología , Corteza Prefrontal/fisiología , Lóbulo Frontal , Imagen por Resonancia Magnética
5.
Phys Chem Chem Phys ; 25(45): 31238-31248, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37955158

RESUMEN

Lowering the Schottky barrier at the metal-semiconductor interface remains a stern challenge in the field of field-effect transistors. Herein, an in-depth investigation was conducted to explore the formation mechanism of the Schottky barrier via interlayer distance and external electric field, utilizing the first-principles approach. Attributed to the vertical asymmetric structure of B2P6, ohmic contact forms at the interface of a graphene/B2P6(001) heterostructure, and an n-type Schottky contact with a Schottky barrier of 0.51 eV forms at the interface of a graphene/B2P6(001̄) heterostructure. Furthermore, the Schottky barrier height and the contact type can be changed by adjusting the interlayer spacing or applying an electric field along the Z direction. A high carrier concentration of 4.65 × 1013 cm-2 is obtained in the graphene/B2P6(001) heterostructure when an external electric field of 0.05 V Å-1 is applied. Verifiably, alterations in the energy band structure are attributed to the redistribution of charges at the interface. The new findings indicate that GR/B2P6 heterostructures are a key candidate for next-generation Schottky field-effect transistor development.

6.
Neuroimage ; 258: 119384, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35709949

RESUMEN

Hierarchical planning (HP) is a strategy that optimizes the planning by storing the steps towards the goal (lower-level planning) into subgoals (higher-level planning). In the framework of model-based reinforcement learning, HP requires the computation through the transition value between higher-level hierarchies. Previous study identified the dmPFC, PMC and SPL were involved in the computation process of HP respectively. However, it is still unclear about how these regions interaction with each other to support the computation in HP, which could deepen our understanding about the implementation of plan algorithm in hierarchical environment. To address this question, we conducted an fMRI experiment using a virtual subway navigation task. We identified the activity of the dmPFC, premotor cortex (PMC) and superior parietal lobe (SPL) with general linear model (GLM) in HP. Then, Dynamic Causal Modelling (DCM) was performed to quantify the influence of the higher- and lower-planning on the connectivity between the brain areas identified by the GLM. The strongest modulation effect of the higher-level planning was found on the dmPFC→right PMC connection. Furthermore, using Parametric Empirical Bayes (PEB), we found the modulation of higher-level planning on the dmPFC→right PMC and right PMC→SPL connections could explain the individual difference of the response time. We conclude that the dmPFC-related connectivity takes the response to the higher-level planning, while the PMC acts as the bridge between the higher-level planning to behavior outcome.


Asunto(s)
Mapeo Encefálico , Corteza Motora , Teorema de Bayes , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Humanos , Imagen por Resonancia Magnética , Corteza Motora/fisiología
7.
Neuroimage ; 258: 119354, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35659997

RESUMEN

Transitive inference (TI) is a critical capacity involving the integration of relevant information into prior knowledge structure for drawing novel inferences on unobserved relationships. To date, the neural correlates of TI remain unclear due to the small sample size and heterogeneity of various experimental tasks from individual studies. Here, the meta-analysis on 32 fMRI studies was performed to detect brain activation patterns of TI and its three paradigms (spatial inference, hierarchical inference, and associative inference). We found the hippocampus, prefrontal cortex (PFC), putamen, posterior parietal cortex (PPC), retrosplenial cortex (RSC), supplementary motor area (SMA), precentral gyrus (PreCG), and median cingulate cortex (MCC) were engaged in TI. Specifically, the RSC was implicated in the associative inference, whereas PPC, SMA, PreCG, and MCC were implicated in the hierarchical inference. In addition, the hierarchical inference and associative inference both evoked activation in the hippocampus, medial PFC, and PCC. Although the meta-analysis on spatial inference did not generate a reliable result due to insufficient amount of investigations, the present work still offers a new insight for better understanding the neural basis underlying TI.


Asunto(s)
Imagen por Resonancia Magnética , Lóbulo Parietal , Aminoacridinas , Giro del Cíngulo , Humanos , Lóbulo Parietal/fisiología , Corteza Prefrontal/fisiología
8.
Horm Behav ; 118: 104634, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31765657

RESUMEN

Circulating levels of testosterone have been positively associated with impulsivity. The present study investigates the effect of testosterone administration on impulsivity in an intertemporal choice task, where participants are given a choice between smaller-sooner rewards and larger-later rewards. Healthy young male participants (n = 111) received a single-dose of 150 mg testosterone gel in a double-blind, placebo-controlled, between-subjects design. At 180 min post-administration, participants performed the decision-making task. Both model-free (i.e., higher indifference point) and model-based (i.e., steeper discounting rate) parameters revealed that testosterone administration increased impulsive choice. This finding supports the hypothesis that exogenous testosterone increases impulsivity among healthy young males in a laboratory task.


Asunto(s)
Conducta de Elección/efectos de los fármacos , Toma de Decisiones/efectos de los fármacos , Conducta Impulsiva/efectos de los fármacos , Testosterona/administración & dosificación , Adolescente , Adulto , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Voluntarios Sanos , Humanos , Masculino , Placebos , Recompensa , Testosterona/farmacocinética , Factores de Tiempo , Adulto Joven
9.
Nature ; 510(7503): 152-6, 2014 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-24739972

RESUMEN

T-helper-17 (TH17) cells have critical roles in mucosal defence and in autoimmune disease pathogenesis. They are most abundant in the small intestine lamina propria, where their presence requires colonization of mice with microbiota. Segmented filamentous bacteria (SFB) are sufficient to induce TH17 cells and to promote TH17-dependent autoimmune disease in animal models. However, the specificity of TH17 cells, the mechanism of their induction by distinct bacteria, and the means by which they foster tissue-specific inflammation remain unknown. Here we show that the T-cell antigen receptor (TCR) repertoire of intestinal TH17 cells in SFB-colonized mice has minimal overlap with that of other intestinal CD4(+) T cells and that most TH17 cells, but not other T cells, recognize antigens encoded by SFB. T cells with antigen receptors specific for SFB-encoded peptides differentiated into RORγt-expressing TH17 cells, even if SFB-colonized mice also harboured a strong TH1 cell inducer, Listeria monocytogenes, in their intestine. The match of T-cell effector function with antigen specificity is thus determined by the type of bacteria that produce the antigen. These findings have significant implications for understanding how commensal microbiota contribute to organ-specific autoimmunity and for developing novel mucosal vaccines.


Asunto(s)
Antígenos Bacterianos/inmunología , Bacterias Grampositivas/inmunología , Intestinos/inmunología , Simbiosis , Células Th17/inmunología , Animales , Antígenos Bacterianos/química , Vacunas Bacterianas , Diferenciación Celular , Epítopos de Linfocito T/química , Epítopos de Linfocito T/inmunología , Bacterias Grampositivas/química , Hibridomas/inmunología , Inmunidad Mucosa/inmunología , Mucosa Intestinal/citología , Mucosa Intestinal/inmunología , Intestino Delgado/citología , Intestino Delgado/inmunología , Intestinos/citología , Listeria monocytogenes/inmunología , Ratones , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Receptores de Antígenos de Linfocitos T/inmunología , Células Th17/citología
10.
Phys Rev Lett ; 117(7): 071802, 2016 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-27563951

RESUMEN

We analyze the energy and zenith angle distributions of the latest two-year IceCube data set of upward-going atmospheric neutrinos to constrain sterile neutrinos at the eV scale in the 3+1 scenario. We find that the parameters favored by a combination of LSND and MiniBooNE data are excluded at more than the 99% C.L. We explore the impact of nonstandard matter interactions on this exclusion and find that the exclusion holds for nonstandard interactions (NSIs) that are within the stringent model-dependent bounds set by collider and neutrino scattering experiments. However, for large NSI parameters subject only to model-independent bounds from neutrino oscillation experiments, the LSND and MiniBooNE data are consistent with IceCube.

11.
Psychoneuroendocrinology ; 161: 106948, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38211451

RESUMEN

Previous research indicates that higher testosterone levels are related to increased aggressive and dominant behaviors, particularly in males. One possible mechanism for these hormone-behavior associations could involve threat perception. However, the causal influence of testosterone on men's recognition of threatening facial expressions remains unknown. Here, we tested the causal effect of exogenous testosterone on men's sensitivity to facial threat by combining a psychophysical task with computational modeling. We administered a single dose (150 mg) of testosterone or placebo gel to healthy young men (n = 120) in a double-blind, placebo-controlled, between-participant design. Participants were presented with morphed emotional faces mixing anger/fear and neutral expressions and made judgments about the emotional expression. Across typical regression analysis, signal detection analysis, and drift diffusion modeling, our results consistently showed that individuals who received testosterone (versus placebo) exhibited a lower perceived sensitivity to angry facial expressions. But we observed no significant effects of testosterone administration on fearful facial expressions. The findings indicate that testosterone attenuates sensitivity to facial threat, especially angry facial expressions, which could lead to a misestimation of others' dominance and an increase in one's own aggressive and dominant behaviors.


Asunto(s)
Expresión Facial , Testosterona , Masculino , Humanos , Testosterona/farmacología , Ira , Emociones , Miedo
12.
iScience ; 27(6): 110007, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38868183

RESUMEN

Inferring prospective outcomes and updating behavior are prerequisites for making flexible decisions in the changing world. These abilities are highly associated with the functions of the orbitofrontal cortex (OFC) in humans and animals. The functional specialization of OFC subregions in decision-making has been established in animals. However, the understanding of how human OFC contributes to decision-making remains limited. Therefore, we studied this issue by examining the information representation and functional interactions of human OFC subregions during inference-based decision-making. We found that the medial OFC (mOFC) and lateral OFC (lOFC) collectively represented the inferred outcomes which, however, were context-general coding in the mOFC and context-specific in the lOFC. Furthermore, the mOFC-motor and lOFC-frontoparietal functional connectivity may indicate the motor execution of mOFC and the cognitive control of lOFC during behavioral updating. In conclusion, our findings support the dissociable functional roles of OFC subregions in decision-making.

13.
Commun Biol ; 7(1): 517, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38693344

RESUMEN

How does the human brain construct cognitive maps for decision-making and inference? Here, we conduct an fMRI study on a navigation task in multidimensional abstract spaces. Using a deep neural network model, we assess learning levels and categorized paths into exploration and exploitation stages. Univariate analyses show higher activation in the bilateral hippocampus and lateral prefrontal cortex during exploration, positively associated with learning level and response accuracy. Conversely, the bilateral orbitofrontal cortex (OFC) and retrosplenial cortex show higher activation during exploitation, negatively associated with learning level and response accuracy. Representational similarity analysis show that the hippocampus, entorhinal cortex, and OFC more accurately represent destinations in exploitation than exploration stages. These findings highlight the collaboration between the medial temporal lobe and prefrontal cortex in learning abstract space structures. The hippocampus may be involved in spatial memory formation and representation, while the OFC integrates sensory information for decision-making in multidimensional abstract spaces.


Asunto(s)
Cognición , Hipocampo , Imagen por Resonancia Magnética , Corteza Prefrontal , Humanos , Hipocampo/fisiología , Hipocampo/diagnóstico por imagen , Masculino , Corteza Prefrontal/fisiología , Corteza Prefrontal/diagnóstico por imagen , Femenino , Cognición/fisiología , Adulto , Adulto Joven , Mapeo Encefálico/métodos , Toma de Decisiones/fisiología
14.
Bioresour Technol ; 393: 130128, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38040313

RESUMEN

Applications of post-denitrification processes are subjected to low reaction rates caused by a lack of carbon resources. To offer a solution for reaction rate promotion, this research found a pilot-scale anaerobic/aerobic/anoxic bioreactor treating 55-120 m3/d low-strength municipal wastewater for 273 days. A short hydraulic retention time (HRT, 5-6 h) and a high nitrogen removal rate (63.2 ± 9.3 g-N/m3·d) were achieved using HRT optimization. The effluent total nitrogen concentration was maintained at 5.8 ± 1.4 mg/L while operating at a high nitrogen loading rate of 86.2 ± 12.8 g-N/m3·d. The short aeration (1.25-1.5 h) minimized the Glycogen loss. The endogenous denitrification rate increased to above 1.0 mg/(g-VSS·h). The functional genus Ca. Competibacter enriched to 2.3 %, guaranteeing the efficient post-denitrification process. Dechloromonas rose to 1.1 %, aiding in the synchronous phosphorus removal. These findings offered fresh insights into AOA processes to achieve energy/cost-saving wastewater treatment.


Asunto(s)
Eliminación de Residuos Líquidos , Purificación del Agua , Aguas del Alcantarillado , Desnitrificación , Anaerobiosis , Nitrógeno , Reactores Biológicos , Fósforo , Nitrificación
15.
Brain Struct Funct ; 228(3-4): 799-813, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36813907

RESUMEN

Social navigation is a dynamic and complex process that requires the collaboration of multiple brain regions. However, the neural networks for navigation in a social space remain largely unknown. This study aimed to investigate the role of hippocampal circuit in social navigation from a resting-state fMRI data. Here, resting-state fMRI data were acquired before and after participants performed a social navigation task. By taking the anterior and posterior hippocampus (HPC) as the seeds, we calculated their connectivity with the whole brain using the seed-based static functional connectivity (sFC) and dynamic FC (dFC) approaches. We found that the sFC and dFC between the anterior HPC and supramarginal gyrus, sFC or dFC between posterior HPC and middle cingulate cortex, inferior parietal gyrus, angular gyrus, posterior cerebellum, medial superior frontal gyrus were increased after the social navigation task. These alterations were related to social cognition of tracking location in the social navigation. Moreover, participants who had more social support or less neuroticism showed a greater increase in hippocampal connectivity. These findings may highlight a more important role of the posterior hippocampal circuit in the social navigation, which is crucial for social cognition.


Asunto(s)
Encéfalo , Hipocampo , Humanos , Hipocampo/diagnóstico por imagen , Mapeo Encefálico , Imagen por Resonancia Magnética , Lóbulo Parietal
16.
Biol Psychol ; 178: 108524, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36801356

RESUMEN

Testosterone is associated with both aggressive and prosocial behavior, which depend on the social context and the trade-off between self- and other-interest. However, little is known about the effects of testosterone on prosocial behavior in a context without such trade-offs. The present study aimed to investigate the effects of exogenous testosterone on prosocial behavior by using a prosocial learning task. Healthy male participants (n =120) received a single dose of testosterone gel in a double-blind, placebo-controlled, between-participants experiment. Participants performed a prosocial learning task in which they were asked to learn to gain rewards for three different recipients, i.e., self, other and computer, by choosing symbols associated with potential rewards. The results showed that testosterone administration increased the learning rates across all the recipient conditions (dother = 1.57; dself = 0.50; dcomputer = 0.99). More importantly, participants in the testosterone group had a higher prosocial learning rate than those in the placebo group (d = 1.57). These findings suggest that testosterone generally enhances reward sensitivity and prosocial learning. The present study corroborates the social status hypothesis, according to which testosterone promotes status-seeking prosocial behavior when it is appropriate to the social context.


Asunto(s)
Agresión , Testosterona , Humanos , Masculino , Testosterona/farmacología , Altruismo , Recompensa , Método Doble Ciego
17.
Psychoneuroendocrinology ; 155: 106321, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37385090

RESUMEN

Fairness concerns play a prominent role in promoting cooperation in human societies. Social preferences involving fairness concern have been associated with individual testosterone levels. However, the causal effects of testosterone administration on fairness-related decision making remain to be elucidated. Here, we used a randomized, double-blind, between-participant design and administered testosterone or placebo gel to 120 healthy young men. Three hours after administration, participants performed a modified Dictator Game from behavioral economics, in which they were asked to choose one of two monetary allocations between themselves and anonymous partners. Participants were either in a position of advantageous inequality (i.e., endowed with more than others) or disadvantageous inequality (i.e., endowed with less than others). Computational modeling showed that inequality-related preferences explained behavior better than competing models. Importantly, compared with the placebo group, the testosterone group showed significantly reduced aversion to advantageous inequality but enhanced aversion to disadvantageous inequality. These findings suggest that testosterone facilitates decisions that prioritize selfish economic motives over fairness concerns, which in turn may boost status-enhancing behaviors.


Asunto(s)
Conducta Social , Testosterona , Humanos , Masculino , Simulación por Computador , Toma de Decisiones , Motivación , Testosterona/farmacología , Método Doble Ciego
18.
Sci Rep ; 12(1): 5393, 2022 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-35354838

RESUMEN

The measurement of neutrino mass ordering (MO) is a fundamental element for the understanding of leptonic flavour sector of the Standard Model of Particle Physics. Its determination relies on the precise measurement of [Formula: see text] and [Formula: see text] using either neutrino vacuum oscillations, such as the ones studied by medium baseline reactor experiments, or matter effect modified oscillations such as those manifesting in long-baseline neutrino beams (LB[Formula: see text]B) or atmospheric neutrino experiments. Despite existing MO indication today, a fully resolved MO measurement ([Formula: see text]) is most likely to await for the next generation of neutrino experiments: JUNO, whose stand-alone sensitivity is [Formula: see text], or LB[Formula: see text]B experiments (DUNE and Hyper-Kamiokande). Upcoming atmospheric neutrino experiments are also expected to provide precious information. In this work, we study the possible context for the earliest full MO resolution. A firm resolution is possible even before 2028, exploiting mainly vacuum oscillation, upon the combination of JUNO and the current generation of LB[Formula: see text]B experiments (NOvA and T2K). This opportunity is possible thanks to a powerful synergy boosting the overall sensitivity where the sub-percent precision of [Formula: see text] by LB[Formula: see text]B experiments is found to be the leading order term for the MO earliest discovery. We also found that the comparison between matter and vacuum driven oscillation results enables unique discovery potential for physics beyond the Standard Model.

19.
FASEB J ; 23(6): 1786-96, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19158154

RESUMEN

Anti-lymphocyte antibodies (Abs) that suppress T-cell chemotactic and other responses to sphingosine 1-phosphate (S1P), but not to chemokines, were found in a lymphopenic patient with recurrent infections. Lymphocyte type 1 S1P receptor (S1P(1)) that transduces S1P chemotactic stimulation was recognized by patient Abs in Western blots of T cells, S1P(1) transfectants, and S1P(1)-hemagglutinin purified by monoclonal anti-hemagglutinin Ab absorption. The amino terminus of S1P(1), but not any extracellular loop, prevented anti-S1P(1) Ab suppression of S1P(1) signaling and T-cell chemotaxis to S1P. Human purified anti-S1P(1) Abs decreased mouse blood lymphocyte levels by a mean of 72%, suppressed mouse T-cell chemotaxis to S1P in vivo, and significantly reduced the severity of dextran sodium sulfate-induced colitis in mice. Human Abs to the amino terminus of S1P(1) suppress T-cell trafficking sufficiently to impair host defense and provide therapeutic immunosuppression.


Asunto(s)
Autoanticuerpos/inmunología , Inmunosupresores/inmunología , Receptores de Lisoesfingolípidos/inmunología , Linfocitos T/inmunología , Anciano , Animales , Antígenos/inmunología , Infecciones Bacterianas/inmunología , Colitis/inmunología , Femenino , Humanos , Lisofosfolípidos/metabolismo , Ratones , Ratones Endogámicos C57BL , Isoformas de Proteínas/genética , Isoformas de Proteínas/inmunología , Receptores de Lisoesfingolípidos/genética , Esfingosina/análogos & derivados , Esfingosina/metabolismo
20.
Zhong Yao Cai ; 33(12): 1909-12, 2010 Dec.
Artículo en Zh | MEDLINE | ID: mdl-21548371

RESUMEN

OBJECTIVE: To study the effects and mechanism of Aconitum vaginatum on proliferation, invasion and metastasis of human lung adenocarcinoma A549 cell lines. METHODS: A549 cells were treated with Aconitum vaginatum at different concentrations, and divided into 4 groups: Aconitum vaginatum 0.01, 0.1, 1 mg/mL groups and control group, respectively. MTT assay was used to evaluate cell proliferation; migration and invasion (with matrigel) assay was conducted in the transwell chamber; gelatin zymography was performed to evaluated the impacts of Aconitum vaginatum on matrix metalloproteinase (MMP)-2, MMP-9. RESULTS: Aconitum vaginatum exhibited a concentration-dependent inhibitory on proliferation and invasion of A549 cells. Aconitum vaginatum was also found to decrease the activity of MMP-2, MMP-9 in a concentration-dependent manner (P < 0.05). CONCLUSION: Aconitum vaginatum can inhibit the proliferation, invasion and metastasis of human adenocarcinoma A549 cell lines, the mechanism maybe deceasing MMP-2, MMP-9 activity.


Asunto(s)
Aconitum/química , Antineoplásicos Fitogénicos/farmacología , Proliferación Celular/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Neoplasias Pulmonares/patología , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Antineoplásicos Fitogénicos/administración & dosificación , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Medicamentos Herbarios Chinos/administración & dosificación , Humanos , Neoplasias Pulmonares/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Invasividad Neoplásica , Metástasis de la Neoplasia
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