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1.
Cell ; 187(3): 676-691.e16, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38306983

RESUMEN

Behavior relies on activity in structured neural circuits that are distributed across the brain, but most experiments probe neurons in a single area at a time. Using multiple Neuropixels probes, we recorded from multi-regional loops connected to the anterior lateral motor cortex (ALM), a circuit node mediating memory-guided directional licking. Neurons encoding sensory stimuli, choices, and actions were distributed across the brain. However, choice coding was concentrated in the ALM and subcortical areas receiving input from the ALM in an ALM-dependent manner. Diverse orofacial movements were encoded in the hindbrain; midbrain; and, to a lesser extent, forebrain. Choice signals were first detected in the ALM and the midbrain, followed by the thalamus and other brain areas. At movement initiation, choice-selective activity collapsed across the brain, followed by new activity patterns driving specific actions. Our experiments provide the foundation for neural circuit models of decision-making and movement initiation.


Asunto(s)
Movimiento , Neuronas , Encéfalo/fisiología , Movimiento/fisiología , Neuronas/fisiología , Tálamo/fisiología , Memoria
2.
Cell ; 185(6): 1065-1081.e23, 2022 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-35245431

RESUMEN

Motor behaviors are often planned long before execution but only released after specific sensory events. Planning and execution are each associated with distinct patterns of motor cortex activity. Key questions are how these dynamic activity patterns are generated and how they relate to behavior. Here, we investigate the multi-regional neural circuits that link an auditory "Go cue" and the transition from planning to execution of directional licking. Ascending glutamatergic neurons in the midbrain reticular and pedunculopontine nuclei show short latency and phasic changes in spike rate that are selective for the Go cue. This signal is transmitted via the thalamus to the motor cortex, where it triggers a rapid reorganization of motor cortex state from planning-related activity to a motor command, which in turn drives appropriate movement. Our studies show how midbrain can control cortical dynamics via the thalamus for rapid and precise motor behavior.


Asunto(s)
Corteza Motora , Movimiento , Tálamo , Animales , Mesencéfalo , Ratones , Corteza Motora/fisiología , Neuronas/fisiología , Tálamo/fisiología
3.
Cell ; 184(14): 3717-3730.e24, 2021 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-34214471

RESUMEN

Neural activity underlying short-term memory is maintained by interconnected networks of brain regions. It remains unknown how brain regions interact to maintain persistent activity while exhibiting robustness to corrupt information in parts of the network. We simultaneously measured activity in large neuronal populations across mouse frontal hemispheres to probe interactions between brain regions. Activity across hemispheres was coordinated to maintain coherent short-term memory. Across mice, we uncovered individual variability in the organization of frontal cortical networks. A modular organization was required for the robustness of persistent activity to perturbations: each hemisphere retained persistent activity during perturbations of the other hemisphere, thus preventing local perturbations from spreading. A dynamic gating mechanism allowed hemispheres to coordinate coherent information while gating out corrupt information. Our results show that robust short-term memory is mediated by redundant modular representations across brain regions. Redundant modular representations naturally emerge in neural network models that learned robust dynamics.


Asunto(s)
Lóbulo Frontal/fisiología , Red Nerviosa/fisiología , Envejecimiento/fisiología , Animales , Conducta Animal , Cerebro/fisiología , Conducta de Elección , Femenino , Luz , Masculino , Ratones , Modelos Neurológicos , Corteza Motora/fisiología , Neuronas/fisiología
4.
Nature ; 563(7729): 113-116, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30333626

RESUMEN

Persistent and ramping neural activity in the frontal cortex anticipates specific movements1-6. Preparatory activity is distributed across several brain regions7,8, but it is unclear which brain areas are involved and how this activity is mediated by multi-regional interactions. The cerebellum is thought to be primarily involved in the short-timescale control of movement9-12; however, roles for this structure in cognitive processes have also been proposed13-16. In humans, cerebellar damage can cause defects in planning and working memory13. Here we show that persistent representation of information in the frontal cortex during motor planning is dependent on the cerebellum. Mice performed a sensory discrimination task in which they used short-term memory to plan a future directional movement. A transient perturbation in the medial deep cerebellar nucleus (fastigial nucleus) disrupted subsequent correct responses without hampering movement execution. Preparatory activity was observed in both the frontal cortex and the cerebellar nuclei, seconds before the onset of movement. The silencing of frontal cortex activity abolished preparatory activity in the cerebellar nuclei, and fastigial activity was necessary to maintain cortical preparatory activity. Fastigial output selectively targeted the behaviourally relevant part of the frontal cortex through the thalamus, thus closing a cortico-cerebellar loop. Our results support the view that persistent neural dynamics during motor planning is maintained by neural circuits that span multiple brain regions17, and that cerebellar computations extend beyond online motor control13-15,18.


Asunto(s)
Cerebelo/fisiología , Lóbulo Frontal/fisiología , Desempeño Psicomotor/fisiología , Animales , Cerebelo/citología , Señales (Psicología) , Femenino , Lóbulo Frontal/citología , Masculino , Ratones , Movimiento/fisiología , Vías Nerviosas , Neuronas/fisiología , Tálamo/citología , Tálamo/fisiología
5.
Phys Chem Chem Phys ; 25(29): 19492-19500, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37448277

RESUMEN

This work reports the refinement of nanoporous copper (NPC) ligaments by introducing the sodium dodecyl sulfate (SDS) surfactant in the dealloying process. The Al80Cu20 (at%) alloy precursor is chemically dealloyed in a mixed solution of NaOH and SDS surfactant, producing NPC with a hierarchical microstructure. Micron-scaled skeletons that build up higher level networks consist of geometrically similar nano-scaled bi-continuous ligament-pore networks at the lower level. It has been found that the size of the ligaments in the lower level networks reduces from ∼32 nm to ∼24 nm with increasing SDS concentration to 1 mM. Further increasing the SDS concentration to 5 mM only leads to a slight ligament size decrease to ∼21 nm. Remarkably, nano-sized cones are formed on the lower level network surface in the dealloying solution containing 1 mM SDS, and the cone number greatly rises when the SDS concentration increases to 5 mM. The surface diffusivity of Cu adatoms is evaluated based on the experimental data, and the refinement of the ligament as well as the formation of cones are associated with the decreased surface diffusivity and the retarded Cu adatom motions with the addition of SDS. Quantum chemical calculations and molecular dynamics simulations are performed to model the adsorption behavior of SDS. It has been found that the SDS-substrate interaction increases with the number of SDS molecules before SDS reaches saturation.

6.
Appl Microbiol Biotechnol ; 107(2-3): 677-689, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36572830

RESUMEN

Pectate lyases (Pels) have a vital function in degradation of the primary plant cell wall and the middle lamella and have been widely used in the industry. In this study, two pectate lyase genes, IDSPel16 and IDSPel17, were cloned from a sheep rumen microbiome. The recombinant enzymes were expressed in Escherichia coli and functionally characterized. Both IDSPel16 and IDSPel17 proteins had an optimal temperature of 60 ℃, and an optimal pH of 10.0. IDSPel16 was relatively stable below 60 °C, maintaining 77.51% residual activity after preincubation at 60 °C for 1 h, whereas IDSPel17 denatured rapidly at 60 °C. IDSPel16 was relatively stable between pH 6.0 and 12.0, after pretreatment for 1 h, retaining over 60% residual activity. IDSPel16 had high activity towards polygalacturonic acid, with a Vmax of 942.90 ± 68.11, whereas IDSPel17 had a Vmax of only 28.19 ± 2.23 µmol/min/mg. Reaction product analyses revealed that IDSPel17 liberated unsaturated digalacturonate (uG2) and unsaturated trigalacturonate (uG3) from the substrate, indicating a typical endo-acting pectate lyase (EC 4.2.2.2). In contrast, IDSPel16 initially generated unsaturated oligogalacturonic acids, then converted these intermediates into uG2 and unsaturated galacturonic acid (uG1) as end products, a unique depolymerization profile among Pels. To the best of our knowledge, the IDSPel16 discovered with both endo-Pel (EC 4.2.2.2) and exo-Pel (EC 4.2.2.9) activities. These two pectate lyases, particularly the relatively thermo- and pH-stable IDSPel16, will be of interest for potential application in the textile, food, and feed industries. KEY POINTS: • Two novel pectate lyase genes, IDSPel16 and IDSPel17, were isolated and characterized from the sheep rumen microbiome. • Both IDSPel16 and IDSPel17 are alkaline pectate lyases, releasing unsaturated digalacturonate and unsaturated trigalacturonate from polygalacturonic acid. • IDSPel16, a bifunctional pectate lyase with endo-Pel (EC 4.2.2.2) and exo-Pel (EC 4.2.2.9) activities, could be a potential candidate for industrial application.


Asunto(s)
Polisacárido Liasas , Rumen , Animales , Ovinos , Rumen/metabolismo , Polisacárido Liasas/metabolismo , Clonación Molecular
7.
Nano Lett ; 22(10): 3904-3913, 2022 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-35522592

RESUMEN

Physiological microenvironment engineering has shown great promise in combating a variety of diseases. Herein, we present the rational design of reinforced and injectable blood-derived protein hydrogels (PDA@SiO2-PRF) composed of platelet-rich fibrin (PRF), polydopamine (PDA), and SiO2 nanofibers that can act as dual-level regulators to engineer the microenvironment for personalized bone regeneration with high efficacy. From the biophysical level, PDA@SiO2-PRF with high stiffness can withstand the external loading and maintaining the space for bone regeneration in bone defects. Particularly, the reinforced structure of PDA@SiO2-PRF provides bone extracellular matrix (ECM)-like functions to stimulate osteoblast differentiation via Yes-associated protein (YAP) signaling pathway. From the biochemical level, the PDA component in PDA@SiO2-PRF hinders the fast degradation of PRF to release autologous growth factors in a sustained manner, providing sustained osteogenesis capacity. Overall, the present study offers a dual-level strategy for personalized bone regeneration by engineering the biophysiochemical microenvironment to realize enhanced osteogenesis efficacy.


Asunto(s)
Hidrogeles , Fibrina Rica en Plaquetas , Regeneración Ósea , Osteogénesis , Fibrina Rica en Plaquetas/metabolismo , Dióxido de Silicio/metabolismo
8.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(1): 57-61, 2023 Jan 10.
Artículo en Zh | MEDLINE | ID: mdl-36585002

RESUMEN

OBJECTIVE: To explore the genetic basis for a child with mental retardation. METHODS: Whole exome sequencing was carried out for the child. Candidate variant was screened based on his clinical features and verified by Sanger sequencing. RESULTS: The child was found to harbor a c.995_1002delAGACAAAA(p.Asp332AlafsTer84) frameshift variant in the SYNGAP1 gene. Bioinformatic analysis suggested it to be pathogenic. The same variant was not detected in either parent. CONCLUSION: The c.995_1002delAGACAAAA(p.Asp332AlafsTer84) frameshift variant of the SYNGAP1 gene probably underlay the mental retardation in this child. Above finding has expanded the spectrum of SYNGAP1 gene variants and provided a basis for the diagnosis and treatment for this child.


Asunto(s)
Discapacidad Intelectual , Niño , Humanos , Discapacidad Intelectual/genética , Mutación del Sistema de Lectura , Secuenciación de Nucleótidos de Alto Rendimiento , Biología Computacional , Heterocigoto , Mutación , Proteínas Activadoras de ras GTPasa/genética
9.
Nature ; 532(7600): 459-64, 2016 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-27074502

RESUMEN

Neural activity maintains representations that bridge past and future events, often over many seconds. Network models can produce persistent and ramping activity, but the positive feedback that is critical for these slow dynamics can cause sensitivity to perturbations. Here we use electrophysiology and optogenetic perturbations in the mouse premotor cortex to probe the robustness of persistent neural representations during motor planning. We show that preparatory activity is remarkably robust to large-scale unilateral silencing: detailed neural dynamics that drive specific future movements were quickly and selectively restored by the network. Selectivity did not recover after bilateral silencing of the premotor cortex. Perturbations to one hemisphere are thus corrected by information from the other hemisphere. Corpus callosum bisections demonstrated that premotor cortex hemispheres can maintain preparatory activity independently. Redundancy across selectively coupled modules, as we observed in the premotor cortex, is a hallmark of robust control systems. Network models incorporating these principles show robustness that is consistent with data.


Asunto(s)
Mapeo Encefálico , Función Ejecutiva/fisiología , Corteza Motora/citología , Corteza Motora/fisiología , Movimiento/fisiología , Neuronas/fisiología , Animales , Cuerpo Calloso/fisiología , Femenino , Luz , Masculino , Memoria a Corto Plazo/fisiología , Ratones , Modelos Neurológicos , Corteza Motora/efectos de la radiación , Movimiento/efectos de la radiación , Neuronas/efectos de la radiación , Optogenética
10.
Environ Res ; 214(Pt 1): 113698, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35779618

RESUMEN

Due to extreme toxicity of the element of thallium (Tl), increasing aqueous Tl pollution incidents have aroused growing concerns. As the prevalent and stable form, i.e., monovalent Tl, the highly efficient removal methodologies of Tl(I) from (waste)water remains limited and challenging. In this study, an advanced oxidation method, the feasibility of using zero valent iron (Fe0) coupled with persulfate (PS) to treat Tl(I)-containing synthetic wastewater was investigated. Its influence parameters, including reaction time, initial Tl concentration, dosages of PS and Fe0, initial and coagulation pH, temperature, coexisting ions and organic matter (NO3-, SO42-, Cl- and HA) were examined. The results revealed that the system can be applied to a wide range of pH and temperature and the reaction equilibrium can be reached in about 30 min. Favorable Tl(I) removal rate (>98%) was observed in the synthetic wastewater with medium and relatively high Tl(I) concentration (≤0.250 mM). The analyses of characterization results including electron spin resonance spectrometer and X-ray photoelectron spectroscopy indicated that ·OH played a vital role in the removal of Tl(I), which was oxidized and removed by co-precipitation. Fe0 can be served as a stable source of Fe2+ to efficiently catalyze PS. The remaining Fe0 can be easily separated because of its magnetism, assuring the promising reusability of the reactant. The study aims to provide references for treatment of real Tl polluted wastewater.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Hierro , Oxidación-Reducción , Talio , Aguas Residuales
11.
Int J Mol Sci ; 23(9)2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-35562946

RESUMEN

Depression is a psychiatric disorder that presents with a persistent depressed mood as the main clinical feature and is accompanied by cognitive impairment. Changes in neuroplasticity and neurogenesis greatly affect depression. Without genetic changes, epigenetic mechanisms have been shown to function by regulating gene expression during the body's adaptation to stress. Studies in recent years have shown that as important regulatory factors in epigenetic mechanisms, microRNAs (miRNAs) play important roles in the development and progression of depression through the regulation of protein expression. Herein, we review the mechanisms of miRNA-mediated neuroplasticity in depression and discus synaptic structural plasticity, synaptic functional plasticity, and neurogenesis. Furthermore, we found that miRNAs regulate neuroplasticity through several signalling pathways to affect cognitive functions. However, these pathways do not work independently. Therefore, we try to identify synergistic correlations between miRNAs and multiple signalling pathways to broaden the potential pathogenesis of depression. In addition, in the future, dual-function miRNAs (protection/injury) are promising candidate biomarkers for the diagnosis of depression, and their regulated genes can potentially be used as target genes for the treatment of depression.


Asunto(s)
Disfunción Cognitiva , MicroARNs , Depresión/genética , Humanos , MicroARNs/metabolismo , Neurogénesis/genética , Plasticidad Neuronal/genética
12.
Exp Cell Res ; 394(2): 112141, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32535033

RESUMEN

Circular RNAs (circRNAs), a special type of non-coding RNA molecules, have been addressed to be implicated in gastric cancer progression. The GSE93541 and GSE83521 microarrays found hsa-circRNA-000670 (hsa-circ-0000670) as an up-regulated circRNAin gastric cancer. We mainly investigated the function and molecular mechanisms of hsa-circ-0000670 involved in gastric cancer. The expression of hsa-circ-0000670 was determined by RT-qPCR to be highly expressed in gastric cancer tissues relative to corresponding adjacent normal tissues, as well as in gastric cancer cell lines relative to normal gastric mucosal epithelial cell line. By conducting EdU, scratch test and Transwell assays, hsa-circ-000670 was found to be a tumor promoter by potentiating the proliferative, invasive and migrating capabilities of gastric cancer cells. Consistently, a tumor-promotive role of hsa-circ-000670 was validated in vivo. Dual-luciferase reporter gene and RIP assays identified the binding of hsa-circ-0000670 to microRNA-384 (miR-384) and the binding of miR-384 to sine oculis-related homeobox 4 (SIX4). The oncogenic potential of hsa-circ-0000670 in gastric cancer cells were inhibited by overexpressed miR-384. Mechanistically, SIX4 was targeted by miR-384 and was upregulated in gastric cancer. High SIX4 expression was suggested to correlate with the poor prognosis of gastric cancer patients. Additionally, silencing of SIX4 delayed tumor growth and progression, which were reversed by overexpression of hsa-circ-0000670. Taken together, hsa-circ-0000670 acts as a tumor promotor in gastric cancer progression and might be a potential target for gastric cancer treatment.


Asunto(s)
Progresión de la Enfermedad , Proteínas de Homeodominio/metabolismo , MicroARNs/metabolismo , ARN Circular/metabolismo , Transducción de Señal , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Transactivadores/metabolismo , Animales , Carcinogénesis/genética , Carcinogénesis/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación hacia Abajo/genética , Regulación Neoplásica de la Expresión Génica , Silenciador del Gen , Proteínas de Homeodominio/genética , Humanos , Masculino , Ratones Desnudos , MicroARNs/genética , Invasividad Neoplásica , Oncogenes , ARN Circular/genética , Transactivadores/genética , Regulación hacia Arriba/genética
13.
Nature ; 519(7541): 51-6, 2015 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-25731172

RESUMEN

Activity in motor cortex predicts specific movements seconds before they occur, but how this preparatory activity relates to upcoming movements is obscure. We dissected the conversion of preparatory activity to movement within a structured motor cortex circuit. An anterior lateral region of the mouse cortex (a possible homologue of premotor cortex in primates) contains equal proportions of intermingled neurons predicting ipsi- or contralateral movements, yet unilateral inactivation of this cortical region during movement planning disrupts contralateral movements. Using cell-type-specific electrophysiology, cellular imaging and optogenetic perturbation, we show that layer 5 neurons projecting within the cortex have unbiased laterality. Activity with a contralateral population bias arises specifically in layer 5 neurons projecting to the brainstem, and only late during movement planning. These results reveal the transformation of distributed preparatory activity into movement commands within hierarchically organized cortical circuits.


Asunto(s)
Corteza Motora/fisiología , Movimiento/fisiología , Vías Nerviosas/fisiología , Animales , Conducta Animal/fisiología , Tronco Encefálico/citología , Tronco Encefálico/fisiología , Electrofisiología , Ratones , Corteza Motora/citología , Vías Nerviosas/citología , Células Piramidales/citología , Células Piramidales/fisiología
14.
Ren Fail ; 43(1): 606-616, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33781160

RESUMEN

BACKGROUND: The present meta-analysis of propensity score-matching studies aimed to compare the long-term survival outcomes and adverse events associated with coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) in patients with chronic kidney disease (CKD). METHODS: Electronic databases were searched for studies comparing CABG and PCI in patients with CKD. The search period extended to 13 February 2021. The primary outcome was all-cause mortality, and the secondary endpoints included myocardial infarction, revascularization, and stroke. Odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CIs) were used to express the pooled effect. Study quality was assessed using the Newcastle-Ottawa scale. The analyses were performed using RevMan 5.3. RESULTS: Thirteen studies involving 18,005 patients were included in the meta-analysis. Long-term mortality risk was significantly lower in the CABG group than in the PCI group (HR: 0.76, 95% CI: 0.70-0.83, p < .001), and similar results were observed in the subgroup analysis of patients undergoing dialysis and for different estimated glomerular filtration rate ranges. The incidence rates of myocardial infarction (OR: 0.25, 95% CI: 0.12-0.54, p < .001) and revascularization (OR: 0.17, 95% CI: 0.08-0.35, p < .001) were lower in the CABG group than in the PCI group, although there were no significant differences in the incidence of stroke between the two groups (OR: 1.24; 95% CI: 0.89-1.73, p > .05). Subgroup analysis among patients on dialysis yielded similar results. CONCLUSIONS: Our propensity score matching analysis revealed that, based on long-term follow-up outcomes, CABG remains superior to PCI in patients with CKD.


Asunto(s)
Puente de Arteria Coronaria/efectos adversos , Intervención Coronaria Percutánea/efectos adversos , Diálisis Renal/efectos adversos , Insuficiencia Renal Crónica/mortalidad , Humanos , Incidencia , Infarto del Miocardio/epidemiología , Infarto del Miocardio/etiología , Puntaje de Propensión , Insuficiencia Renal Crónica/terapia , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología
15.
Am J Physiol Cell Physiol ; 319(1): C93-C104, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31747529

RESUMEN

Esophageal squamous cell carcinoma (ESCC) ranks among the five most common cancers in China and has a five-year survival rate of less than 15%. The transcription factor ATPase-family AAA-domain-containing protein 2 (ATAD2) has potential as a therapeutic target in various tumors, and microarray-based gene expression profiling reveals dysregulation of ATAD2 specifically in ESCC. Here we investigated whether ATAD2 could mediate a regulation of cancer stem cell (CSC) biological functions in ESCC. Immunohistochemical staining, reverse transcription quantitative polymerase chain reaction, and Western blot assays all revealed upregulation of ATAD2 in ESCC tissues and cell lines, which furthermore correlated with progression of ESCC. In loss-of-function experiments, silencing of ATAD2 inhibited activation of the Hedgehog signaling pathway, as indicated by reduced expression of glioma-associated oncogene family zinc finger 1 (Gli1), smoothened frizzled class receptor (SMO), and patched 1 (PTCH1). Investigations with 5-ethynyl-2'-deoxyuridine (EdU), Transwell assay, scratch test, flow cytometry, and colony formation assay showed that silencing of ATAD2 or inhibiting the Hedgehog signaling decreased the proliferation, invasion, and migration abilities along with colony formation, but elevated the apoptosis rate of CSCs. Furthermore, in vivo experiments validated the suppressive effect of siRNA-mediated ATAD2 silencing on tumor growth in nude mice. Thus, downregulation of ATAD2 can seemingly restrain the malignant phenotypes of ESCC cells through inhibition of the Hedgehog signaling pathway.


Asunto(s)
ATPasas Asociadas con Actividades Celulares Diversas/deficiencia , Proteínas de Unión al ADN/deficiencia , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas de Esófago/metabolismo , Proteínas Hedgehog/antagonistas & inhibidores , Proteínas Hedgehog/metabolismo , Células Madre Neoplásicas/metabolismo , ATPasas Asociadas con Actividades Celulares Diversas/genética , Anciano , Animales , Línea Celular Tumoral , Proteínas de Unión al ADN/genética , Regulación hacia Abajo/fisiología , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago/genética , Carcinoma de Células Escamosas de Esófago/patología , Femenino , Proteínas Hedgehog/genética , Humanos , Masculino , Ratones , Ratones Desnudos , Ratones SCID , Persona de Mediana Edad , Células Madre Neoplásicas/patología , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
16.
Curr Pain Headache Rep ; 24(4): 14, 2020 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-32072323

RESUMEN

PURPOSE OF REVIEW: Transcutaneous electrical nerve stimulation (TENS) is widely used as a non-pharmacological approach for pain relief in a variety of clinical conditions. This manuscript aimed to review the basic mechanisms and clinical applications regarding the use of TENS for alleviating the peripheral (PNP) and central neuropathic pain (CNP). RECENT FINDINGS: Basic studies on animal models showed that TENS could alleviate pain by modulating neurotransmitters and receptors in the stimulation site and its upper levels, including the spinal cord, brainstem, and brain. Besides, many clinical studies have investigated the efficacy of TENS in patients with CNP (caused by spinal cord injury, stroke, or multiple sclerosis) and PNP (induced by diabetes, cancer, or herpes zoster). Most clinical trials have demonstrated the efficacy of TENS in attenuating neuropathic pain and suggested that appropriate stimulation parameters (e.g., stimulation frequency and intensity) were critical to improving the analgesic effects of TENS. However, there are some conflicting findings related to the efficacy of TENS in relieving neuropathic pain. With optimized stimulation parameters, TENS would be effective in attenuating neuropathic pain. To obtain sufficient evidence to support the use of TENS in the clinic, researchers recommended performing multicenter clinical trials with optimized TENS protocols for the treatment of various CNP and PNP.


Asunto(s)
Neuralgia/terapia , Estimulación Eléctrica Transcutánea del Nervio/métodos , Animales , Humanos , Manejo del Dolor/métodos
17.
Ecotoxicol Environ Saf ; 202: 110874, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32619890

RESUMEN

The adverse impacts of detrimental thallium (Tl) contamination are of increasing concerns to sustainable development. Herein, the contents, distributions and sources of Tl and potential toxic elements (PTEs) (Pb, As, Cr, Cu, Ni, Co, Sb, Cd and U) were investigated in sediments collected in Gaofeng River, which has been contaminated by long-term mining activities, located in Yunfu City, Southern China. Results indicated that excessive Tl levels were found in sediments (1.80-16.70 mg/kg). Sequential extraction procedure indicated that despite a large amount of Tl entrapped in residual fraction, a significant level of Tl (0.28-2.34 mg/kg) still exhibited in geochemically labile fractions, which was easy for Tl mobilization and availability. Pb isotope tracing method further confirmed that the pyrite exploitations may be the prime contaminated contributor (47-76%) to these sediments. These findings highlight that it is essential to establish more effective measures for Tl contamination control and call for engineered remediation countermeasures towards polluted river sediments.


Asunto(s)
Monitoreo del Ambiente , Talio/análisis , Contaminantes Químicos del Agua/análisis , China , Ciudades , Contaminación Ambiental , Sedimentos Geológicos/química , Hierro , Isótopos , Metales Pesados/análisis , Minería , Ríos/química , Sulfuros
18.
J Neurosci ; 38(24): 5441-5455, 2018 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-29798890

RESUMEN

Neocortical pyramidal neurons with somata in layers 5 and 6 are among the most visually striking and enigmatic neurons in the brain. These deep-layer pyramidal neurons (DLPNs) integrate a plethora of cortical and extracortical synaptic inputs along their impressive dendritic arbors. The pattern of cortical output to both local and long-distance targets is sculpted by the unique physiological properties of specific DLPN subpopulations. Here we revisit two broad DLPN subpopulations: those that send their axons within the telencephalon (intratelencephalic neurons) and those that project to additional target areas outside the telencephalon (extratelencephalic neurons). While neuroscientists across many subdisciplines have characterized the intrinsic and synaptic physiological properties of DLPN subpopulations, our increasing ability to selectively target and manipulate these output neuron subtypes advances our understanding of their distinct functional contributions. This Viewpoints article summarizes our current knowledge about DLPNs and highlights recent work elucidating the functional differences between DLPN subpopulations.


Asunto(s)
Neocórtex/citología , Células Piramidales/citología , Animales , Humanos , Neocórtex/fisiología , Células Piramidales/fisiología
19.
J Neurosci Res ; 97(10): 1253-1265, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31240758

RESUMEN

Imbalances between cellular K+ efflux and influx are considered to be involved in cerebral ischemia-reperfusion (I/R) injury. High-potassium pretreatment alleviates this injury, but the underlying molecular mechanism is unclear. In this study, we sought to investigate whether high-potassium preconditioning enhances cerebral tolerance to I/R injury through an anti-apoptotic mechanism. Adult male Sprague-Dawley rats were randomly divided into four groups (n = 40/group): a sham-operated group, normal saline group (3.2 ml/kg saline, intravenous (IV)), and low-dose and high-dose potassium chloride (KCl) groups (40 and 80 mg/kg KCl solution, IV, respectively). Subsequently, the rats underwent 90 min of middle cerebral artery occlusion (MCAO) followed by 24 hr of reperfusion (MCAO/R). Neurological deficit scores, 2,3,5-triphenyltetrazolium chloride (TTC) staining, hematoxylin and eosin staining, and TUNEL assay were used to assess neural injury. The expression of apoptotic proteins, brain potassium levels, mitochondrial function and oxidative stress were detected to explore the potential mechanism. After 24 hr of reperfusion, in both KCl treatment groups, neurological deficits and the cerebral infarct volume were reduced, and the apoptosis index of neurons was decreased. Furthermore, high-potassium preconditioning increased brain K+ , adenosine triphosphate (ATP), cytochrome c oxidase (COX) levels, reduced malondialdehyde level, improved Na+ /K+ -ATPase, succinic dehydrogenase and superoxide dismutase activities, upregulated anti-apoptotic protein expression, and downregulated pro-apoptotic protein expression. This study suggests that high-potassium preconditioning enhanced cerebral tolerance to I/R injury in a rat MCAO/R model. The protective mechanism may involve apoptosis inhibition via preservation of intracellular K+ and improvement of mitochondrial function.


Asunto(s)
Isquemia Encefálica/fisiopatología , Encéfalo/irrigación sanguínea , Cloruro de Potasio/farmacología , Daño por Reperfusión/fisiopatología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Precondicionamiento Isquémico/métodos , Masculino , Ratas , Ratas Sprague-Dawley
20.
J Cell Biochem ; 119(5): 4050-4060, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29232009

RESUMEN

This study aims to investigate the influence of the Wnt/ß-catenin signaling pathway on apoptosis, migration, and invasion of transplanted hepatocellular carcinoma (HCC) cells after transcatheter arterial chemoembolization (TACE) in rat models. A total of 80 rats were grouped into sham, TACE, Wnt-C59, and TACE + Wnt-C59 groups (n = 20). Ten days after model establishment, 10 rats in each group were executed to perform pathological examination and follow-up experiment, and the remaining 10 rats in each group were reared to observe the survival condition. RT-qPCR and Western blotting were applied to determine the expressions of Wnt1, ß-catenin, cyclin D1, c-met, vimentin, E-cadherin, and vascular endothelial growth factor (VEGF). ELISA was performed to measure the serum alpha-fetoprotein (AFP) content of rats. Flow cytometry was used to evaluate cell apoptosis rate and transwell assay to examine cell migration and invasion. Compared with the TACE group, the Wnt-C59 and TACE + Wnt-C59 groups showed increased apoptosis and survival time (the TACE + Wnt-C59 group > the Wnt-C59 group). Compared with the sham group, the TACE + Wnt-C59 groups showed decreased cancer tissue weight and expressions of Wnt1, ß-catenin, cyclin D1, vimentin, c-met, and VEGF, but increased E-cadherin expression. Compared with the TACE group, the Wnt-C59 and TACE + Wnt-C59 groups showed decreased AFP level, migration, and invasion (the TACE + Wnt-C59 group < the Wnt-C59 group). These findings indicate inhibition of the Wnt/ß-catenin signaling pathway improves therapeutic effect on TACE via suppressing migration, invasion, and promoting apoptosis of transplanted HCC cells in rats.


Asunto(s)
Apoptosis , Carcinoma Hepatocelular/terapia , Movimiento Celular , Quimioembolización Terapéutica , Neoplasias Hepáticas/terapia , Proteínas de Neoplasias/metabolismo , Vía de Señalización Wnt , beta Catenina/metabolismo , Animales , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Invasividad Neoplásica , Ratas , Ratas Sprague-Dawley
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