RESUMEN
Motivational deficits in patients with schizophrenia adversely affect various domains of daily living. This symptom in everyday life situations manifests in a complex behavioral pattern whose root cannot be simplified to an impaired reward-motivation scheme. This study aimed to identify impairment of the salience network that underlies motivational deficits seen in patients with schizophrenia in real-life situations. During the functional magnetic resonance imaging scan, 20 patients with schizophrenia and 20 normal controls performed a task mimicking real-life situations, in which an avatar proposed participation in a daily activity with either an intrinsic or extrinsic reward. Group and type-of-reward effects were evaluated with respect to brain activity. Further, psychophysiological interactions were analyzed for the dorsal anterior cingulate cortex (dACC) and insula, which are the key nodes of the salience network. The acceptance of the proposal was significantly higher for intrinsic than for extrinsic rewards in controls, whereas patients showed no difference. The imaging results showed a group effect in the dACC, right insula, thalamus, and lingual gyrus. The dACC showed negative contrast interaction with regions of the left dorsolateral prefrontal cortex, and the right insula showed positive contrast interaction with the occipital gyrus and precentral gyrus. These results suggest that patients exhibit no different participation behavior between activities with intrinsic and extrinsic rewards, which can be explained by the floor effect. Disrupted salience processing in schizophrenia including aberrant salience network and a disconnection of the salience and reward networks may account for the lack of motivation for daily activities.
Asunto(s)
Actividades Cotidianas , Corteza Cerebral/fisiopatología , Motivación/fisiología , Red Nerviosa/fisiopatología , Esquizofrenia/fisiopatología , Tálamo/fisiopatología , Adulto , Corteza Cerebral/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/diagnóstico por imagen , Recompensa , Esquizofrenia/diagnóstico por imagen , Tálamo/diagnóstico por imagenRESUMEN
BPG2 (Brz-insensitive pale green 2) is a dark-repressible and light-inducible gene that is required for the greening process in Arabidopsis. Light pulse experiments suggested that light-regulated gene expression of BPG2 is mediated by phytochrome. The T-DNA insertion mutant bpg2-2 exhibited a reduced level of chlorophyll and carotenoid pigmentation in the plastids. Measurements of time resolved chlorophyll fluorescence and of fluorescence emission at 77 K indicated defective photosystem II and altered photosystem I functions in bpg2 mutants. Kinetic analysis of chlorophyll fluorescence induction suggested that the reduction of the primary acceptor (QA) is impaired in bpg2. The observed alterations resulted in reduced photosynthetic efficiency as measured by the electron transfer rate. BPG2 protein is localized in the plastid stroma fraction. Co-immunoprecipitation of a formaldehyde cross-linked RNA-protein complex indicated that BPG2 protein binds with specificity to chloroplast 16S and 23S ribosomal RNAs. The direct physical interaction with the plastid rRNAs supports an emerging model whereby BPG2 provides light-regulated ribosomal RNA processing functions, which are rate limiting for development of the plastid and its photosynthetic apparatus.
Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Cloroplastos/genética , Proteínas de Unión al GTP/genética , Regulación de la Expresión Génica de las Plantas/efectos de la radiación , ARN Ribosómico 16S/genética , ARN Ribosómico 23S/genética , Arabidopsis/fisiología , Arabidopsis/efectos de la radiación , Arabidopsis/ultraestructura , Proteínas de Arabidopsis/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Cloroplastos/metabolismo , Proteínas de Unión al GTP/metabolismo , Inmunoprecipitación , Luz , Mutagénesis Insercional , Cebollas/genética , Cebollas/metabolismo , Fotosíntesis , Complejo de Proteína del Fotosistema I/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Fitocromo/genética , Fitocromo/metabolismo , Estomas de Plantas/metabolismo , ARN del Cloroplasto/genética , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismoRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Cordyceps militaris, one of traditional herbal ingredient in oriental medicine, has been known to promote anticancer and immunomodulatory activities in vitro and in vivo. However, the biological mechanism of anticancer activity has been unknown. OBJECTIVE: To investigate the effect of Cordyceps militaris extract on expression of interferon gamma (IFN-gamma) through interlukin-18 (IL-18) induction and its biological mechanism in vitro and in vivo. MATERIALS AND METHODS: Mice were administrated orally with solution extracted from Cordyceps militaris. The transcription level of IL-18 and IFN-gamma production were measured by reverse transcriptase polymerase chain reaction (RT-PCR) and immunohistochemistry. RAW 264.7 cells were transiently transfected with pCATp1 and pCATp2 for IL-18 promoter functional analysis. RESULTS: Cordyceps militaris extracts treatment significantly induced level of IL-18 transcription in mouse brain and liver and enhanced IL-18 transcription level and activated the IFN-gamma production in RAW 264.7 cells. Furthermore, Cordyceps militaris extract led to increase the activity of pCATp1 construct containing the 5' franking region of IL-18 promoter in RAW 264.7 cells. CONCLUSION: Cordyceps militaris extract induced IL-18 mRNA level via enhancing of P1 promoter region result in activation of IFN-gamma production, indicating its potential as an immune activator or anticancer drug.