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1.
BMJ Open ; 12(8): e060767, 2022 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-35926987

RESUMEN

INTRODUCTION: COVID-19 is a highly infectious disease, characterised by respiratory, physical and psychological dysfunctions. Rehabilitation could effectively alleviate the symptoms and promote recovery of the physical and mental health of patients with COVID-19. Recently, rehabilitation medical institutions have issued clinical practice guidelines (CPGs) and expert consensus statements involving recommendations for rehabilitation assessments and rehabilitation therapies for COVID-19. This systematic review aims to assess the methodological quality and reporting quality of the guidance documents, evaluate the heterogeneity of the recommendations and summarise the recommendations with respect to rehabilitation assessments and rehabilitation therapies for COVID-19 to provide a quick reference for front-line clinicians, therapists and patients as well as reasonable suggestions for future guidelines. METHODS AND ANALYSIS: The electronic databases including PubMed, Embase, Chinese Biomedical Literature Database (CBM), Chinese Science and Technology Periodical Database (VIP), Wanfang Database and China National Knowledge Infrastructure (CNKI) and websites of governments or organisations (eg, National Guideline Clearinghouse, Guidelines International Network, National Institute for Health and Clinical Excellence, Scottish Intercollegiate Guidelines Network and WHO) will be searched for eligible CPGs and expert consensus statements from inception to August 2022. CPGs and expert consensus statements published in Chinese or English and presenting recommendations for modern functional rehabilitation techniques and/or traditional Chinese medicine rehabilitation techniques for COVID-19 will be included. Reviews, interpretations, old versions of CPGs and expert consensus statements and those for the management of other diseases during the pandemic will be excluded. Two reviewers will independently review each article, extract data, appraise the methodological quality following the Appraisal of Guidelines for Research & Evaluation II tool and assess the reporting quality with the Reporting Items for Practice Guidelines in Healthcare statement. The Measurement Scale of Rate of Agreement will be used to evaluate the heterogeneity of the recommendations in different CPGs and expert consensus statements. Agreement between reviewers will be calculated using the intraclass correlation coefficient. We will also summarise the recommendations for rehabilitation in patients with COVID-19. The results will be narratively described and presented as tables or figures. ETHICS AND DISSEMINATION: Ethics approval is not needed for this systematic review because information from published documents will be used. The findings will be submitted for publication in a peer-reviewed journal and reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PROSPERO REGISTRATION NUMBER: CRD42020190761.


Asunto(s)
COVID-19 , COVID-19/rehabilitación , China , Consenso , Humanos , Medicina Tradicional China , Pandemias , Guías de Práctica Clínica como Asunto , Proyectos de Investigación , Revisiones Sistemáticas como Asunto
2.
Front Neurosci ; 16: 1097450, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36778899

RESUMEN

Background: Previous functional magnetic resonance imaging studies indicated that acupuncture could activate the brain regions in patients with migraine. However, these studies showed inconsistent results. This activation likelihood estimation (ALE) meta-analysis aimed to investigate the consistent activated change of brain regions between pre- and post-acupuncture treatment in migraineurs. Methods: We conducted a literature search in PubMed, Embase, Web of Science, the Cochrane Library, the China National Knowledge Infrastructure, the Chinese Science and Technology Periodical Database, the Wanfang Database, and the Chinese Biomedical Literature Database from their inception to 18 August, 2022, to obtain articles assessing the functional magnetic resonance imaging changes of acupuncture for migraine. Two investigators independently performed literature selection, data extraction, and quality assessment. The methodological quality was assessed with a modified version of the checklist. The reporting quality of interventions among included studies was evaluated by the Revised Standards for Reporting Interventions in Clinical Trials of Acupuncture (STRICTA). Our meta-analysis was conducted according to the GingerALE software. The Jackknife sensitivity analysis was used to assess the robustness of the results. Results: 14 articles were finally included according to the eligible criteria. Regarding the immediate effect of acupuncture on migraine, the ALE meta-analysis demonstrated that the deactivation regions were mainly located in the superior frontal gyrus, and middle frontal gyrus (uncorrected P < 0.001). The ALE meta-analysis of the cumulative effect showed that the activation regions were the thalamus, superior frontal gyrus, posterior lobe of the cerebellum, insula, middle frontal gyrus, precentral gyrus, anterior cingulate, and the deactivation brain regions were located in the transverse temporal gyrus, postcentral gyrus, superior temporal gyrus, anterior cingulate, parahippocampal gyrus, inferior parietal lobule, and inferior occipital gyrus (uncorrected P < 0.001). Conclusion: Acupuncture could activate multiple brain areas related with the regulation of pain conduction, processing, emotion, cognition, and other brain regions in patients with migraine. In the future, the combination of multiple imaging technologies could be a new approach to deeply investigate the central mechanism of acupuncture for migraine.

3.
Nat Prod Res ; 35(23): 5066-5074, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32524844

RESUMEN

Four previously undescribed hydroxypropionylated d-glucose derivatives, astrabhotins A-D (1-4), along with ten known compounds α-d-glucose (5), ß-d-glucose (6), quebrachitol (7), 3-hydroxypropionic acid (8), oleic acid (9), isoliquiritigenin (10), liquiritigenin (11), odoratin (12), 7ß-hydroxysitosterol (13) and daucosterol (14), were isolated from the roots of Astragalus bhotanensis. Their structures were elucidated based on the analyses of extensive spectroscopic data and physicochemical properties. Astrabhotin A (1) reduced the writhing response remarkably with 52.5% inhibition by acetic acid induced writhing test. The analgesic effect of 1 was stronger than the standard drug aspirin. In addition, compounds 1 and 3 showed significant antioxidant activities with IC50 values of 9.9 ± 0.2 and 7.9 ± 0.4 µg/mL, and exhibited weak or moderate cytotoxicity against HepG2 cells with IC50 values of 106.6 ± 2.7 and 42.0 ± 0.9 µg/mL, respectively.[Figure: see text].


Asunto(s)
Planta del Astrágalo , Glucosa , Antioxidantes/farmacología , Extractos Vegetales , Raíces de Plantas
4.
Medicine (Baltimore) ; 98(33): e16786, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31415383

RESUMEN

INTRODUCTION: To investigate the effectiveness and safety of electromyography (EMG) biofeedback therapy in improving motor dysfunction among children with cerebral palsy (CP). METHODS AND ANALYSIS: The following databases will be searched: PubMed, EMBASE, ScienceDirect, the Cochrane Library, China National Knowledge infrastructure (CNKI), Technology Periodical Database (VIP), WanFang Data and China Biology Medicine (CBM) from inception to June 2019. All relevant randomized controlled trials (RCTs) utilizing EMG biofeedback therapy for CP will be included. The main outcome is the Gross Motor Function Measure (GMFM). Additional outcomes such as the Modified Ashworth Scale (MAS), Integral Electromyogram (iEMG), Composite Spasticity Scale (CSS), passive range of motion (PROM) or other related outcomes will be included, adverse effects of EMG biofeedback therapy and comparators will also be included. Two reviewers will screen studies, extract data and assess quality independently. Review Manager 5.3 will be used to assess the risk of bias, data synthesis, and subgroup analysis. ETHICS AND DISSEMINATION: This systematic review does not require formal ethical approval because all data will be analyzed anonymously. Results will provide a general overview and evidence concerning the effectiveness and safety of EMG biofeedback therapy for children with CP. The findings of this systematic review will be disseminated through peer-reviewed publications or conference presentations.


Asunto(s)
Biorretroalimentación Psicológica , Parálisis Cerebral/fisiopatología , Electromiografía , Niño , Humanos , Metaanálisis como Asunto
5.
Zhongguo Zhong Yao Za Zhi ; 44(5): 1026-1033, 2019 Mar.
Artículo en Chino | MEDLINE | ID: mdl-30989865

RESUMEN

The LPS-induced RAW264. 7 cells inflammation model was used as a carrier to investigate the in vitro anti-inflammation effects of Jingfang n-butanol extraction(JFNE) isolated fraction A and explore its preliminary anti-inflammation mechanism by observing the regulatory effect on PI3 K/AKT signaling pathway and NF-κB pathway. The RAW264. 7 cells inflammation model was established by stimulating with LPS for 12 h. After 3 h pre-treatment with fraction A,the contents of interleukin-6(IL-6),interleukin-1ß(IL-1ß) and tumor necrosis factor(TNF-α) in the supernatant of RAW264. 7 cells inflammation model were determined by ELISA and the contents of NO in supernatant were assayed by Griess. Reverse transcription-polymerase chain reaction(RT-PCR) method was used to determine the expression of IL-6,IL-1ß,TNF-α,IFN-γ,i NOS,PI3 K,AKT,CHUK,NF-κB1 and Rela mRNA in RAW264. 7 inflammatory cells,and the expression levels of phosphorylated and total PI3 K/AKT protein,NF-κB p50,p65,p-p65,p105 protein in cells were determined via Western blot. In addition,LC-MS and database were used to identify the possible chemical constituents in fraction A. The results showed that fraction A could significantly reduce the release levels of NO,IL-6,IL-1ß and TNF-α in the supernatant and the expression of IL-6,IL-1ß,TNF-α,IFN-γ,i NOS,PI3 K,AKT,CHUK,NF-κB1 and Rela mRNA in RAW264. 7 inflammation model cells(P<0. 05 or P<0. 01) and significantly inhibit the phosphorylation expression levels of PI3 K and AKT protein and mRNA expressions(P<0. 05 or P<0. 01). Moreover,fraction A could significantly reduce the levels of NF-κB p50,p-p65 and i NOS protein,as well as NF-κB1,Rela mRNA expressions in RAW264. 7 cells,and increase the expression of CHUK gene.A total of 196 compounds were identified from fraction A in the composition analysis,and isoobtusilactone,5-O-methyl-vismitol,emebel(embelin) and prim-O-glucosylcimifugin showed high contents. The results all above showed that fraction A had a certain antiinflammatory effect in LPS-induced RAW264. 7 inflammation model cells,and its anti-inflammatory effects may be related to its regulatory effect on the activation of PI3 K/AKT signaling pathway and NF-kappa B signaling pathway. In addition,emblin may be its effective anti-inflammation chemical composition.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Inflamación , Macrófagos/efectos de los fármacos , Extractos Vegetales/farmacología , 1-Butanol , Animales , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Lipopolisacáridos , Ratones , Células RAW 264.7 , Transducción de Señal , Factor de Necrosis Tumoral alfa/metabolismo
6.
Zhongguo Zhong Yao Za Zhi ; 44(4): 781-786, 2019 Feb.
Artículo en Chino | MEDLINE | ID: mdl-30989892

RESUMEN

To investigate the relationship between anti-depressant effect and hippocampal nerve growth of Xiaoyao San,the inflammatory model of hippocampal neuron was induced by lipopolysaccharide( LPS). The effect of Xiaoyao San serum( final concentration of4%,8%) on the cell proliferation activity was detected by immunofluorescence,the levels of BDNF and ß-NGF in the supernatant of hippocampal neurons were detected by ELISA,and the expressions of BDNF,NGF,Trk B,Trk A and CREB mRNA in cell lysate of hippocampal neuron were detected by PCR. Western blot was used to detect the expressions of Trk B,CREB,p-CREB and SYP protein in cell lysate of hippocampal neuron,and to reveal the neuroprotective effect and mechanism of Xiaoyao San. The results showed that8% Xiaoyao San serum could significantly increase in Brdu/Neu N ratio( P<0. 01). 4%,8% Xiaoyao San serum could significantly improve the levels of BDNF and ß-NGF in supernatant( P<0. 05 or P<0. 01),up-regulate the expression of BDNF,NGF,Trk B,Trk A,CREB mRNA and Trk B,p-CREB,SYP protein in cell lysate( P< 0. 05 or P< 0. 01). 8% Xiaoyao San serum could significantly increase CREB protein in cell lysate( P<0. 05),and elevate in p-CREB/CREB ratio( P<0. 01). All the above results indicate that Xiaoyao San has a certain protective effect on LPS induced hippocampal neuron injury,which suggests that the protective effect of Xiaoyao San is related to the promotion of hippocampal nerve growth,which is one of its antidepressant mechanisms.


Asunto(s)
Medicamentos Herbarios Chinos , Factor Neurotrófico Derivado del Encéfalo , Hipocampo , Lipopolisacáridos , Neuronas
7.
Huan Jing Ke Xue ; 39(10): 4644-4652, 2018 Oct 08.
Artículo en Chino | MEDLINE | ID: mdl-30229613

RESUMEN

Using sodium acetate as the carbon source, sludge settling ability (settleability) was investigated under three processes:AAO nitrogen and phosphorus removal(process Ⅰ), AO nitrification-denitrification (process Ⅱ), and aerobic carbon removal (process Ⅲ). The succession of microbial community structures in sludge was traced, the content and composition of microbial metabolites were monitored, and the effects of operational mode on sludge settleability were analyzed. The results showed that the settleability of process Ⅰ was the best, followed by process Ⅲ and Ⅱ. Under the different operating conditions, the dominant bacteria and microbial community structure of the system changed significantly. The relative amount of Thiothrix was the dominant bacteria affecting the sludge settleability. The abundances of Thiothrix were only 0.08% and 1.51% with fresh sludge and in process Ⅰ; this abundance increased to 9.41% in process Ⅱ and decreased to 4.29% in process Ⅲ. The anaerobic zone of process I had an inhibitory effect on the growth of the bacterium, while the anoxic zone of process Ⅱ stimulated its dominant growth. At the same time, comparison showed that the microbial population diversity was highest in process Ⅰ. followed by processes Ⅱ and Ⅲ. The introduction of anoxic and anaerobic zones led to the increase of system function and environmental complexity, and increased microbial community diversity. Analyses of extracellular polymeric substances (EPS) and fluorescence characteristics showed that the changes in microbial community structure had a significant effect on the composition and content of EPS, which aggravated the process of improving or deteriorating settleability. The sludge settleability was found to be positively correlated with the ratio of protein and polysaccharide in loosely bound EPS.


Asunto(s)
Bacterias/clasificación , Reactores Biológicos/microbiología , Desnitrificación , Nitrificación , Aguas del Alcantarillado/microbiología , Matriz Extracelular de Sustancias Poliméricas/química , Fósforo/aislamiento & purificación , Eliminación de Residuos Líquidos
8.
J Neurosci ; 36(25): 6680-90, 2016 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-27335400

RESUMEN

UNLABELLED: Arginase 1 deficiency is a urea cycle disorder associated with hyperargininemia, spastic diplegia, loss of ambulation, intellectual disability, and seizures. To gain insight on how loss of arginase expression affects the excitability and synaptic connectivity of the cortical neurons in the developing brain, we used anatomical, ultrastructural, and electrophysiological techniques to determine how single-copy and double-copy arginase deletion affects cortical circuits in mice. We find that the loss of arginase 1 expression results in decreased dendritic complexity, decreased excitatory and inhibitory synapse numbers, decreased intrinsic excitability, and altered synaptic transmission in layer 5 motor cortical neurons. Hepatic arginase 1 gene therapy using adeno-associated virus rescued nearly all these abnormalities when administered to neonatal homozygous knock-out animals. Therefore, gene therapeutic strategies can reverse physiological and anatomical markers of arginase 1 deficiency and therefore may be of therapeutic benefit for the neurological disabilities in this syndrome. SIGNIFICANCE STATEMENT: These studies are one of the few investigations to try to understand the underlying neurological dysfunction that occurs in urea cycle disorders and the only to examine arginase deficiency. We have demonstrated by multiple modalities that, in murine layer 5 cortical neurons, a gradation of abnormalities exists based on the functional copy number of arginase: intrinsic excitability is altered, there is decreased density in asymmetrical and perisomatic synapses, and analysis of the dendritic complexity is lowest in the homozygous knock-out. With neonatal administration of adeno-associated virus expressing arginase, there is near-total recovery of the abnormalities in neurons and cortical circuits, supporting the concept that neonatal gene therapy may prevent the functional abnormalities that occur in arginase deficiency.


Asunto(s)
Arginasa/uso terapéutico , Terapia Genética , Hiperargininemia/patología , Hiperargininemia/terapia , Corteza Motora/fisiología , Recuperación de la Función/fisiología , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Amoníaco/sangre , Animales , Animales Recién Nacidos , Arginasa/genética , Arginasa/metabolismo , Modelos Animales de Enfermedad , Hiperargininemia/sangre , Técnicas In Vitro , Ratones , Ratones Transgénicos , Corteza Motora/citología , Corteza Motora/ultraestructura , Red Nerviosa/patología , Red Nerviosa/fisiología , Red Nerviosa/ultraestructura , Neuronas/fisiología , Neuronas/ultraestructura , Picrotoxina/farmacología , Bloqueadores de los Canales de Sodio/farmacología , Sinapsis/ultraestructura , Tetrodotoxina/farmacología
9.
BMC Neurosci ; 17: 2, 2016 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-26733225

RESUMEN

BACKGROUND: Periventricular leukomalacia (PVL) is the leading cause of neurological disabilities including motor and cognitive deficits in premature infants. Periventricular leukomalacia is characterized by damage to the white matter in the immature brain, but the mechanisms by which damage to immature white matter results in widespread deficits of cognitive and motor function are unclear. The thalamocortical system is crucial for human consciousness and cognitive functions, and impaired development of the cortico-thalamic projections in the neonatal period is implicated to contribute importantly to abnormalities of cognitive function in children with PVL. RESULTS: In this study, using a mouse model of PVL, we sought to test the hypothesis that PVL-like injury affects the different components of the thalamocortical circuitry that can be defined by vesicular glutamate transporters 1 and 2 (vGluT1 and vGluT2), both of which are required for glutamatergic synaptic transmission in the central nervous system. We combined immunocytochemistry and immuno-electron microscopy to investigate changes in cortico-thalamic synapses which were specifically identified by vGluT1 immunolabeling. We found that a drastic reduction in the density of vGluT1 labeled profiles in the somatosensory thalamus, with a reduction of 72-74 % in ventroposterior (VP) nucleus and a reduction of 42-82 % in thalamic reticular nucleus (RTN) in the ipsilateral side of PVL mice. We further examined these terminals at the electron microscopic level and revealed onefold-twofold decrease in the sizes of vGluT1 labeled corticothalamic terminals in VP and RTN. The present study provides anatomical and ultrastructural evidence to elucidate the cellular mechanisms underlying alteration of thalamic circuitry in a mouse model of PVL, and reveals that PVL-like injury has a direct impact on the corticothalamic projection system. CONCLUSIONS: Our findings provide the first set of evidence showing that the thalamocortical circuitry is affected and vulnerable in PVL mice, supporting a working model in which vGluT1 defined corticothalamic synapses are altered in PVL mice, and vGluT2 defined thalamocortical synapses are associated with such changes, leading to the compromised thalamocortical circuitry in the PVL mice. Our study demonstrates that the thalamocortical circuitry is highly vulnerable to hypoxia-ischemia in the PVL model, thus identifying a novel target site in PVL pathology.


Asunto(s)
Corteza Cerebral/ultraestructura , Modelos Animales de Enfermedad , Hipoxia-Isquemia Encefálica/complicaciones , Leucomalacia Periventricular/patología , Sinapsis/ultraestructura , Tálamo/ultraestructura , Animales , Corteza Cerebral/metabolismo , Leucomalacia Periventricular/etiología , Leucomalacia Periventricular/metabolismo , Ratones , Ratones Endogámicos C57BL , Vías Nerviosas/metabolismo , Vías Nerviosas/ultraestructura , Sinapsis/metabolismo , Tálamo/metabolismo , Proteína 1 de Transporte Vesicular de Glutamato/metabolismo , Proteína 2 de Transporte Vesicular de Glutamato/metabolismo
10.
J Comp Neurol ; 519(6): 1181-95, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-21344408

RESUMEN

Relatively little is known about the subcellular localization of low threshold Ca²+ channels (T-channels) in the brain. Using immunocytochemical labeling and preembedding immunoperoxidase and silver-enhanced immunogold electron microscopy, we localized T-channel subunit Ca(v) 3.3 in rodent cerebral cortex and thalamus. Double immunofluorescent staining demonstrated that Ca(v) 3.3-labeled neurons in cerebral cortex are a subgroup of GABAergic interneurons that coexpress calbindin and in half of the cases parvalbumin. In the thalamus, virtually all reticular nucleus (RTN) neurons were immunopositive for Ca(v) 3.3, while neurons in dorsal thalamic nuclei were nonimmunoreactive. At the electron microscopic (EM) level, in cortical layers IV-V and RTN neurons, Ca(v) 3.3 immunoreactivity was mainly associated with membranes of dendrites but with some localization in cytoplasm. None was found in axon terminals. In cortex, ≈73% of immunogold particles were present in close proximity to synaptic contacts (<0.5 µm from the postsynaptic density), while 27% were distributed along membranes at extrasynaptic sites (>0.5 µm from the postsynaptic density). In RTN, ≈57% particles were evenly distributed along perisynaptic membranes and the remaining 43% of particles were diffusely localized at extrasynaptic membranes. The density of particles along the dendritic membranes of cortical neurons was 40% higher than in RTN neurons. These results suggest that Ca(v) 3.3 plays a role in regulating GABAergic neurons whose actions underlie thalamocortical rhythmicity.


Asunto(s)
Canales de Calcio Tipo T/metabolismo , Corteza Cerebral/citología , Neuronas/metabolismo , Tálamo/citología , Ácido gamma-Aminobutírico/metabolismo , Animales , Corteza Cerebral/metabolismo , Dendritas/ultraestructura , Humanos , Inmunohistoquímica , Macaca mulatta , Ratones , Ratones Endogámicos C57BL , Neuronas/ultraestructura , Ratas , Ratas Wistar , Tálamo/metabolismo
11.
J Comp Neurol ; 507(2): 1258-76, 2008 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-18181146

RESUMEN

The ventral posterior nucleus of the thalamus (VP) receives two major sets of excitatory inputs, one from the ascending somatosensory pathways originating in the dorsal horn, dorsal column nuclei, and trigeminal nuclei, and the other originating from the cerebral cortex. Both systems use glutamate as neurotransmitter, as do the thalamocortical axons relaying somatosensory information from the VP to the primary somatosensory cortex (SI). The synapses formed by these projection systems differ anatomically, physiologically, and in their capacity for short-term synaptic plasticity. Glutamate uptake into synaptic vesicles and its release at central synapses depend on two isoforms of vesicular glutamate transporters, VGluT1 and VGluT2. Despite ample evidence of their complementary distribution, some instances exist of co-localization in the same brain areas or at the same synapses. In the thalamus, the two transcripts coexist in cells of the VP and other nuclei but not in the posterior or intralaminar nuclei. We show that the two isoforms are completely segregated at VP synapses, despite their widespread expression throughout the dorsal and ventral thalamus. We present immunocytochemical, ultrastructural, gene expression, and connectional evidence that VGluT1 in the VP is only found at corticothalamic synapses, whereas VGluT2 is only found at terminals made by axons originating in the spinal cord and brainstem. By contrast, the two VGluT isoforms are co-localized in thalamocortical axon terminals targeting layer IV, but not in those targeting layer I, suggesting the presence of two distinct projection systems related to the core/matrix pattern of organization of thalamocortical connectivity described in other mammals.


Asunto(s)
Ácido Glutámico/metabolismo , Terminales Presinápticos/metabolismo , Núcleos Talámicos Ventrales/metabolismo , Proteína 1 de Transporte Vesicular de Glutamato/metabolismo , Proteína 2 de Transporte Vesicular de Glutamato/metabolismo , Vías Aferentes/metabolismo , Vías Aferentes/ultraestructura , Animales , Biomarcadores/análisis , Biomarcadores/metabolismo , Mapeo Encefálico/métodos , Tronco Encefálico/metabolismo , Tronco Encefálico/ultraestructura , Vías Eferentes/metabolismo , Vías Eferentes/ultraestructura , Expresión Génica/fisiología , Hibridación in Situ , Ratones , Microscopía Confocal , Microscopía Inmunoelectrónica , Terminales Presinápticos/ultraestructura , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Corteza Somatosensorial/metabolismo , Corteza Somatosensorial/ultraestructura , Médula Espinal/metabolismo , Médula Espinal/ultraestructura , Transmisión Sináptica/fisiología , Núcleos Talámicos Ventrales/ultraestructura , Proteína 1 de Transporte Vesicular de Glutamato/genética , Proteína 2 de Transporte Vesicular de Glutamato/genética
12.
J Neurosci ; 24(40): 8885-95, 2004 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-15470155

RESUMEN

Switching of the NMDA receptor 2A (NR2A) and NR2B subunits at NMDA receptors is thought to underlie the functional changes that occur in NMDA receptor properties during the developmental epoch when neural plasticity is most pronounced. The cellular expression of NR2A and NR2B and the NR2 synaptic binding protein postsynaptic density-95 (PSD-95) was examined in the mouse somatosensory cortex and thalamus from postnatal day 2 (P2) to P15 using reverse transcription-PCR, in situ hybridization histochemistry, and immunocytochemistry. The localization of NR2A and NR2B subunits and PSD-95 was then studied at synapses in layer IV of somatosensory cortex and in the ventral posterior nucleus of the thalamus using high-resolution immunoelectron microscopy. At both cortical and thalamic synapses, a quantitative switch in the dominant synaptic subunit from NR2B to NR2A was accompanied by a similar change in the cellular expression of NR2A but not of NR2B. Synaptic PSD-95 developed independently, although both NR2A and NR2B colocalized with PSD-95. Displacement of NR2B subunits from synapses was not accompanied by an increase in an extrasynaptic pool of this subunit. Thus, the switch in synaptic NR2 subunit predominance does not occur by changes in expression or displacement from synapses and may reflect the formation of new synapses from which NR2B is lacking.


Asunto(s)
Receptores de N-Metil-D-Aspartato/metabolismo , Corteza Somatosensorial/crecimiento & desarrollo , Corteza Somatosensorial/metabolismo , Sinapsis/metabolismo , Tálamo/crecimiento & desarrollo , Tálamo/metabolismo , Animales , Homólogo 4 de la Proteína Discs Large , Guanilato-Quinasas , Péptidos y Proteínas de Señalización Intracelular , Proteínas de la Membrana , Ratones , Ratones Endogámicos ICR , Microscopía Inmunoelectrónica , Proteínas del Tejido Nervioso/análisis , Proteínas del Tejido Nervioso/metabolismo , Subunidades de Proteína/análisis , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , ARN Mensajero/metabolismo , Receptores de N-Metil-D-Aspartato/análisis , Receptores de N-Metil-D-Aspartato/genética , Corteza Somatosensorial/citología , Sinapsis/química , Sinapsis/ultraestructura , Tálamo/citología
13.
J Comp Neurol ; 466(4): 457-67, 2003 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-14566942

RESUMEN

The mounting physiological evidence for low-resistance electrical coupling between thalamic and cortical neurons contrasts with a lack of morphological data on gap junctions in thalamus and cortex. Connexin-36 is a neuronally specific protein associated with low-resistance gap junctions in the central nervous system. Connexin-36 localization was studied in the mouse somatosensory cortex and thalamus by using immunocytochemistry and immunoelectron microscopy. Expression of connexin-36 immunoreactivity is widespread in the forebrain and significantly enhanced in the barrel cortex and thalamic reticular nucleus during the second postnatal week, but it extends to other thalamic nuclei as well. At the electron microscopic level, pre- and postembedding immunogold labeling revealed that 70-76% of connexin-36-immunolabeled particles were localized at focal sites on apposed plasma membranes of cortical and thalamic dendrites; approximately 5% of the particles were associated with parasynaptic membranes; but on no occasion could overt, morphologically identifiable gap junctions be demonstrated in association with connexin-36 immunoreactivity. The widespread distribution of focal concentrations of connexin-36 subunits could provide a basis for the electrical coupling that exists between cortical and reticular thalamic neurons, but morphologically definable gap junctions may be too small to be adequately visualized by conventional immunoelectron microscopy.


Asunto(s)
Corteza Cerebral/metabolismo , Conexinas/biosíntesis , Neuronas/metabolismo , Tálamo/metabolismo , Animales , Corteza Cerebral/ultraestructura , Uniones Comunicantes/metabolismo , Inmunohistoquímica , Ratones , Ratones Endogámicos ICR , Microscopía Inmunoelectrónica , Vías Nerviosas/metabolismo , Vías Nerviosas/ultraestructura , Neuronas/ultraestructura , Tálamo/ultraestructura , Proteína delta-6 de Union Comunicante
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