RESUMO
Anxiety-related disorders respond to cognitive behavioral therapies, which involved the medial prefrontal cortex (mPFC). Previous studies have suggested that subregions of the mPFC have different and even opposite roles in regulating innate anxiety. However, the specific causal targets of their descending projections in modulating innate anxiety and stress-induced anxiety have yet to be fully elucidated. Here, we found that among the various downstream pathways of the prelimbic cortex (PL), a subregion of the mPFC, PL-mediodorsal thalamic nucleus (MD) projection, and PL-ventral tegmental area (VTA) projection exhibited antagonistic effects on anxiety-like behavior, while the PL-MD projection but not PL-VTA projection was necessary for the animal to guide anxiety-related behavior. In addition, MD-projecting PL neurons bidirectionally regulated remote but not recent fear memory retrieval. Notably, restraint stress induced high-anxiety state accompanied by strengthening the excitatory inputs onto MD-projecting PL neurons, and inhibiting PL-MD pathway rescued the stress-induced anxiety. Our findings reveal that the activity of PL-MD pathway may be an essential factor to maintain certain level of anxiety, and stress increased the excitability of this pathway, leading to inappropriate emotional expression, and suggests that targeting specific PL circuits may aid the development of therapies for the treatment of stress-related disorders.
Assuntos
Ansiedade , Vias Neurais , Córtex Pré-Frontal , Estresse Psicológico , Animais , Ansiedade/psicologia , Ansiedade/fisiopatologia , Masculino , Estresse Psicológico/psicologia , Estresse Psicológico/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Vias Neurais/fisiopatologia , Vias Neurais/fisiologia , Camundongos , Medo/fisiologia , Medo/psicologia , Camundongos Endogâmicos C57BL , Área Tegmentar Ventral/fisiopatologia , Tálamo/fisiopatologia , Núcleo Mediodorsal do Tálamo/fisiologia , Núcleo Mediodorsal do Tálamo/fisiopatologiaRESUMO
The adult brain retains a high repopulation capacity of astrocytes after deletion, and both mature astrocytes in the neocortex and neural stem cells in neurogenic regions possess the potential to generate astrocytes. However, the origin and the repopulation dynamics of the repopulating astrocytes after deletion remain largely unclear. The number of astrocytes is reduced in the medial prefrontal cortex (mPFC) of patients with depression, and selective elimination of mPFC astrocytes is sufficient to induce depression-like behaviors in rodents. However, whether astrocyte repopulation capacity is impaired in depression is unknown. In this study, we used different transgenic mouse lines to genetically label different cell types and demonstrated that in the mPFC of normal adult mice of both sexes, mature astrocytes were a major source of the repopulating astrocytes after acute deletion induced by an astrocyte-specific toxin, L-alpha-aminoadipic acid (L-AAA), and astrocyte regeneration was accomplished within two weeks accompanied by reversal of depression-like behaviors. Furthermore, re-ablation of mPFC astrocytes post repopulation led to reappearance of depression-like behaviors. In adult male mice subjected to 14-day chronic restraint stress, a well-validated mouse model of depression, the number of mPFC astrocytes was reduced; however, the ability of mPFC astrocytes to repopulate after L-AAA-induced deletion was largely unaltered. Our study highlights a potentially beneficial role for repopulating astrocytes in depression and provides novel therapeutic insights into enhancing local mature astrocyte generation in depression.
Assuntos
Astrócitos , Depressão , Camundongos Transgênicos , Córtex Pré-Frontal , Animais , Astrócitos/metabolismo , Córtex Pré-Frontal/metabolismo , Masculino , Depressão/genética , Depressão/patologia , Feminino , Camundongos Endogâmicos C57BL , Camundongos , Modelos Animais de Doenças , Restrição Física , Ácido 2-Aminoadípico , Estresse Psicológico/patologia , Estresse Psicológico/metabolismoRESUMO
Drugs acting on dopamine D2 receptors are widely used for the treatment of several neuropsychiatric disorders, including schizophrenia and depression. Social deficits are a core symptom of these disorders. Pharmacological manipulation of dopamine D2 receptors (Drd2), a Gi-coupled subtype of dopamine receptors, in the medial prefrontal cortex (mPFC) has shown that Drd2 is implicated in social behaviors. However, the type of neurons expressing Drd2 in the mPFC and the underlying circuit mechanism regulating social behaviors remain largely unknown. Here, we show that Drd2 were mainly expressed in pyramidal neurons in the mPFC and that the activation of the Gi-pathway in Drd2+ pyramidal neurons impaired social behavior in male mice. In contrast, the knockdown of D2R in pyramidal neurons in the mPFC enhanced social approach behaviors in male mice and selectively facilitated the activation of mPFC neurons projecting to the nucleus accumbens (NAc) during social interaction. Remarkably, optogenetic activation of mPFC-to-NAc-projecting neurons mimicked the effects of conditional D2R knockdown on social behaviors. Altogether, these results demonstrate a cell type-specific role for Drd2 in the mPFC in regulating social behavior, which may be mediated by the mPFC-to-NAc pathway.
Assuntos
Células Piramidais , Receptores de Dopamina D2 , Camundongos , Masculino , Animais , Receptores de Dopamina D2/metabolismo , Células Piramidais/fisiologia , Neurônios/metabolismo , Córtex Pré-Frontal/metabolismo , Núcleo Accumbens/fisiologia , Comportamento SocialRESUMO
EphB6 belongs to the receptor tyrosine kinase, whose low expression is associated with shorter survival of colorectal cancer (CRC) patients. But the role and mechanism of EphB6 in the progression of CRC need further study. In addition, EphB6 was mainly expressed in intestinal neurons. But how EphB6 is involved in functions of intestinal neurons has not been known. In our study, we constructed a mouse xenograft model of CRC by injecting CMT93 cells into the rectum of EphB6-deficient mice. We found that the deletion of EphB6 in mice promoted tumor growth of CMT93 cells in a xenograft model of CRC, which was independent of changes in the gut microbiota. Interestingly, inhibition of intestinal neurons by injecting botulinum toxin A into rectum of EphB6-deficient mice could eliminate the promotive effect of EphB6 deficiency on tumor growth in the xenograft model of CRC. Mechanically, the deletion of EphB6 in mice promoted the tumor growth in CRC by increasing GABA in the tumor microenvironment. Furthermore, EphB6 deficiency in mice increased the expression of synaptosomal-associated protein 25 in the intestinal myenteric plexus, which mediated the release of GABA. Our study concluded that EphB6 knockout in mice promotes tumor growth of CMT93 cells in a xenograft model of CRC by modulating GABA release. Our study found a new regulating mechanism of EphB6 on the tumor progression in CRC that is dependent on intestinal neurons.
Assuntos
Comunicação Celular , Neoplasias Colorretais , Humanos , Animais , Camundongos , Neoplasias Colorretais/metabolismo , Intestinos/patologia , Neurônios/metabolismo , Neurônios/patologia , Ácido gama-Aminobutírico , Microambiente TumoralRESUMO
Long-term potentiation (LTP) in the hippocampus is the most studied form of synaptic plasticity. Temporal integration of synaptic inputs is essential in synaptic plasticity and is assumed to be achieved through Ca2+ signaling in neurons and astroglia. However, whether these two cell types play different roles in LTP remain unknown. Here, we found that through the integration of synaptic inputs, astrocyte inositol triphosphate (IP3) receptor type 2 (IP3R2)-dependent Ca2+ signaling was critical for late-phase LTP (L-LTP) but not early-phase LTP (E-LTP). Moreover, this process was mediated by astrocyte-derived brain-derived neurotrophic factor (BDNF). In contrast, neuron-derived BDNF was critical for both E-LTP and L-LTP. Importantly, the dynamic differences in BDNF secretion play a role in modulating distinct forms of LTP. Moreover, astrocyte- and neuron-derived BDNF exhibited different roles in memory. These observations enriched our knowledge of LTP and memory at the cellular level and implied distinct roles of astrocytes and neurons in information integration.
Assuntos
Astrócitos , Fator Neurotrófico Derivado do Encéfalo , Astrócitos/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hipocampo/metabolismo , Potenciação de Longa Duração/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/metabolismoRESUMO
Neuroplasticity in the medial prefrontal cortex (mPFC) is essential for fear extinction, the process of which forms the basis of the general therapeutic process used to treat human fear disorders. However, the underlying molecules and local circuit elements controlling neuronal activity and concomitant induction of plasticity remain unclear. Here we show that sustained plasticity of the parvalbumin (PV) neuronal network in the infralimbic (IL) mPFC is required for fear extinction in adult male mice and identify the involvement of neuregulin 1-ErbB4 signalling in PV network plasticity-mediated fear extinction. Moreover, regulation of fear extinction by basal medial amygdala (BMA)-projecting IL neurons is dependent on PV network configuration. Together, these results uncover the local molecular circuit mechanisms underlying mPFC-mediated top-down control of fear extinction, suggesting alterative therapeutic approaches to treat fear disorders.
Assuntos
Extinção Psicológica , Medo , Animais , Extinção Psicológica/fisiologia , Medo/fisiologia , Masculino , Camundongos , Neuregulina-1 , Plasticidade Neuronal/fisiologia , Parvalbuminas , Córtex Pré-Frontal/fisiologia , Receptor ErbB-4RESUMO
erbb4 is a known susceptibility gene for schizophrenia. Chandelier cells (ChCs, also known as axo-axonic cells) are a distinct GABAergic interneuron subtype that exclusively target the axonal initial segment, which is the site of pyramidal neuron action potential initiation. ChCs are a source of ErbB4 expression and alterations in ChC-pyramidal neuron connectivity occur in the medial prefrontal cortex (mPFC) of schizophrenic patients and animal models of schizophrenia. However, the contribution of ErbB4 in mPFC ChCs to the pathogenesis of schizophrenia remains unknown. By conditional deletion or knockdown of ErbB4 from mPFC ChCs, we demonstrated that ErbB4 deficits led to impaired ChC-pyramidal neuron connections and cognitive dysfunctions. Furthermore, the cognitive dysfunctions were normalized by L-838417, an agonist of GABAAα2 receptors enriched in the axonal initial segment. Given that cognitive dysfunctions are a core symptom of schizophrenia, our results may provide a new perspective for understanding the etiology of schizophrenia and suggest that GABAAα2 receptors may be potential pharmacological targets for its treatment.
Assuntos
Disfunção Cognitiva/fisiopatologia , Neurônios GABAérgicos/fisiologia , Interneurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Células Piramidais/fisiologia , Receptor ErbB-4/fisiologia , Esquizofrenia/fisiopatologia , Animais , Comportamento Animal , Masculino , Potenciais da Membrana , Camundongos Knockout , Receptor ErbB-4/genéticaRESUMO
The redox-neutral cascade dearomatization of indoles with o-aminobenzaldehydes has been realized via the hydride transfer strategy, achieving the condition- and substrate-controlled divergent synthesis of tetrahydroquinoline-fused spiroindolenines. The integration of hydride transfer-involved C(sp3)-H functionalization with dearomatization provides a promising platform for the construction of structurally diverse molecules.
RESUMO
A Brønsted acid-catalyzed α-C(sp3)-H amination of cyclic amines using hydrazines as coupling partners has been reported. This methodology provides a unique protocol to the one-step assembly of tetrahydro[1,3,4]triazepines via [1,5]-hydride transfer-initiated C(sp3)-H amination. This reaction features mild conditions, good yields, and high atom economy.
RESUMO
Medium spiny neurons (MSNs), the major GABAergic projection neurons in the striatum, are implicated in many neuropsychiatric diseases such as schizophrenia, but the underlying mechanisms remain unclear. We found that a deficiency in Erbb4, a schizophrenia risk gene, in MSNs of the nucleus accumbens (NAc) core, but not the dorsomedial striatum, markedly induced schizophrenia-like behaviors such as hyperactivity, abnormal marble-burying behavior, damaged social novelty recognition, and impaired sensorimotor gating function in male mice. Using immunohistochemistry, Western blot, RNA interference, electrophysiology, and behavior test studies, we found that these phenomena were mediated by increased GABAA receptor α1 subunit (GABAAR α1) expression, which enhanced inhibitory synaptic transmission on MSNs. These results suggest that Erbb4 in MSNs of the NAc core may contribute to the pathogenesis of schizophrenia by regulating GABAergic transmission and raise the possibility that GABAAR α1 may therefore serve as a new therapeutic target for schizophrenia.SIGNIFICANCE STATEMENT Although ErbB4 is highly expressed in striatal medium spiny neurons (MSNs), its role in this type of neuron has not been reported previously. The present study demonstrates that Erbb4 deletion in nucleus accumbens (NAc) core MSNs can induce schizophrenia-like behaviors via elevated GABAA receptor α1 subunit (GABAAR α1) expression. To our knowledge, this is the first evidence that ErbB4 signaling in the MSNs is involved in the pathology of schizophrenia. Furthermore, restoration of GABAAR α1 in the NAc core, but not the dorsal medium striatum, alleviated the abnormal behaviors. Here, we highlight the role of the NAc core in the pathogenesis of schizophrenia and suggest that GABAAR α1 may be a potential pharmacological target for its treatment.
Assuntos
Transtornos Mentais/fisiopatologia , Neurônios/metabolismo , Núcleo Accumbens/fisiopatologia , Receptor ErbB-4/metabolismo , Receptores de GABA-A/metabolismo , Esquizofrenia/fisiopatologia , Animais , Comportamento Animal , Regulação da Expressão Gênica , Masculino , Transtornos Mentais/etiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Inibição Neural , Receptor ErbB-4/genética , Distribuição Tecidual , Regulação para CimaRESUMO
Depression is a chronic, recurring, and serious mood disorder that afflicts up to 20% of the global population. The monoamine hypothesis has dominated our understanding of the pharmacotherapy of depression for more than half a century; however, our understanding of the pathophysiology and pathogenesis of major depression has lagged far behind. Astrocytes are the most abundant and versatile cells in the brain, participating in most, if not all, of brain functions as both a passive housekeeper and an active player. Mounting evidence from clinical, preclinical and post-mortem studies has revealed a decrease in the number or density of astrocytes and morphological and functional astroglial atrophy in patients with major depressive disorder (MDD) and in animal models of depression. Furthermore, currently available antidepressant treatments at least partially exert their therapeutic effects on astrocytes. More importantly, dysfunctional astrocytes lead to depressive-like phenotypes in animals. Together, current studies point to astroglial pathology as the potential root cause of MDD. Thus, a shift from a neuron-centric to an astrocyte-centric cause of MDD has gained increasing attention during the past two decades. Here we will summarize the current evidence supporting the hypothesis that MDD is a disease of astrocyte pathology and highlight previous studies on promising strategies that directly target astrocytes for the development of novel antidepressant treatments.
Assuntos
Astrócitos/patologia , Encéfalo/patologia , Transtorno Depressivo/patologia , Animais , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Transtorno Depressivo/tratamento farmacológico , HumanosRESUMO
Interleukin-17 (IL-17), a pleiotropic proinflammatory cytokine, is reported to be significantly generated by a distinct subset of CD4+ T-cells, upgrading cancer-elicited inflammation and preventing cancer cells from immune surveillance. T-helper (Th)17 cells produced from naive CD4+ T cells have recently been renowned and generally accepted, gaining eminence in cancer studies and playing the effective role in context of cancer. Th17 cells are the main source of IL-17-secreting cells, It was found that other cell types produced this cytokine as well, including Group 3 innate lymphoid cells (ILC3), δγT cells, invariant natural killer T (iNKT) cells, lymphoid-tissue inducer (LTi)-like cells and Natural killer (NK) cells. Th17-associated cytokines give impetus to tumor progression, or inducing angiogenesis and metastasis. This review demonstrates an understanding on how the pro- or antitumor function of Th17 cells and IL-17 may change cancer progression, leading to the appearance of complex and pivotal biologic activities in tumor.
Assuntos
Imunidade Inata/imunologia , Interleucina-17/imunologia , Neoplasias/imunologia , Neoplasias/patologia , Células Th17/imunologia , Microambiente Tumoral/imunologia , Animais , Medicina Baseada em Evidências , Humanos , Modelos ImunológicosRESUMO
Cytochrome P450 OleTJE has attracted much attention for its ability to catalyze the decarboxylation of long chain fatty acids to generate alkenes, which are not only biofuel molecule, but also can be used broadly for making lubricants, polymers and detergents. In this study, the molecular basis of the binding mechanism of P450 OleTJE for arachidic acid, myristic acid, and caprylic acid was investigated by utilizing conventional molecular dynamics simulation and binding free energy calculations. Moreover, random acceleration molecular dynamics (RAMD) simulations were performed to uncover the most probable access/egress channels for different fatty acids. The predicted binding free energy shows an order of arachidic acid < myristic acid < caprylic acid. Key residues interacting with three substrates and residues specifically binding to one of them were identified. The RAMD results suggest the most likely channel for arachidic acid, myristic acid, and caprylic acid are 2e/2b, 2a and 2f/2a, respectively. It is suggested that the reaction is easier to carry out in myristic acid bound system than those in arachidic acid and caprylic acid bound system based on the distance of Hß atom of substrate relative to P450 OleTJE Compound I states. This study provided novel insight to understand the substrate preference mechanism of P450 OleTJE and valuable information for rational enzyme design for short chain fatty acid decarboxylation.
Assuntos
Caprilatos/química , Sistema Enzimático do Citocromo P-450/química , Ácidos Eicosanoicos/química , Ácido Mirístico/química , Catálise , Cinética , Simulação de Dinâmica Molecular , Oxirredução , Ligação Proteica , Conformação Proteica , Transdução de Sinais , Especificidade por Substrato , TermodinâmicaRESUMO
BACKGROUND: Tricholoma mongolicum Imai is a well-known edible and medicinal mushroom which in recent years has attracted increasing attention because of its bioactivities. In this study, water-soluble polysaccharides were extracted from T. mongolicum Imai by cellulase-assisted extraction and their antioxidant activities were investigated. RESULTS: In order to improve the yield of polysaccharides, four variables, cellulase amount (X1 ), pH (X2 ), temperature (X3 ) and extraction time (X4 ), were investigated with a Box-Behnken design. The optimal conditions were predicted to be cellulase amount of 20 g kg(-1) , pH of 4.0, temperature of 50 °C and extraction time of 127 min, with a predicted polysaccharide yield of 190.1 g kg(-1) . The actual yield of polysaccharides under these conditions was 189.6 g kg(-1) , which matched the predicted value well. The crude polysaccharides were purified to obtain four fractions, and characterization of each was carried out. In addition, antioxidant properties of four polysaccharides assessed by 1,1-diphenyl-2-picryldydrazyl (DPPH) and hydroxyl radical-scavenging assays indicated that polysaccharides from T. mongolicum Imai (TMIPs) possessed antioxidant activity in a dose-dependent manner. CONCLUSION: TMIPs show moderate antioxidant activities in vitro. Therefore it is suggested that TMIPs are potential natural antioxidants for use in functional foods. © 2016 Society of Chemical Industry.
Assuntos
Antioxidantes/isolamento & purificação , Celulase/metabolismo , Misturas Complexas/isolamento & purificação , Aditivos Alimentares/isolamento & purificação , Carpóforos/química , Polissacarídeos Fúngicos/isolamento & purificação , Tricholoma/química , Algoritmos , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/metabolismo , Sequência de Carboidratos , China , Misturas Complexas/biossíntese , Misturas Complexas/química , Aditivos Alimentares/análise , Aditivos Alimentares/química , Aditivos Alimentares/metabolismo , Alimentos em Conserva/análise , Alimentos em Conserva/economia , Sequestradores de Radicais Livres/análise , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/metabolismo , Carpóforos/metabolismo , Polissacarídeos Fúngicos/análise , Polissacarídeos Fúngicos/biossíntese , Polissacarídeos Fúngicos/química , Temperatura Alta , Concentração de Íons de Hidrogênio , Modelos Químicos , Peso Molecular , Estatística como Assunto , Fatores de Tempo , Tricholoma/metabolismoRESUMO
Disturbed development of the parvalbumin-positive fast-spiking (FS) interneurons in the prefrontal cortex (PFC) is closely associated with many neuropsychiatric disorders such as schizophrenia and autism. FS interneurons form at least 2 microcircuits in the PFC: one with pyramidal neurons (FS-PN) through chemical synapses; the other with other FS interneurons (FS-FS) via chemical and electrical synapses. It is currently unknown when and how these circuits are established in the PFC during early development. Here, we used G42 mice, in which FS interneurons are specifically labeled with enhanced green fluorescent protein, to make dual whole-cell recordings from postnatal day 3 (P3) to P30 to study the development of FS interneuronal networks in the PFC. We found that FS interneurons were poorly developed in terms of the membrane and network properties during the first postnatal week, both of which exhibited an abrupt maturation during the second postnatal week. The development of FS interneuronal microcircuits lasted throughout early adulthood. Thus, our data suggest that FS interneurons might not be involved in generating cortical oscillatory activity and γ oscillations during the first postnatal week. Our data also indicate an independent development of electrical and chemical synapses among FS interneuronal networks during the early period.
Assuntos
Interneurônios/fisiologia , Rede Nervosa/crescimento & desenvolvimento , Rede Nervosa/fisiologia , Córtex Pré-Frontal/crescimento & desenvolvimento , Córtex Pré-Frontal/fisiologia , Envelhecimento/fisiologia , Animais , Western Blotting , Fenômenos Eletrofisiológicos/fisiologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Feminino , Corantes Fluorescentes , Junções Comunicantes/fisiologia , Glutamato Descarboxilase/metabolismo , Técnicas In Vitro , Masculino , Camundongos , Sinapses/fisiologia , Ácido gama-Aminobutírico/fisiologiaRESUMO
erbb4 is a susceptibility gene for schizophrenia and ErbB4 signals have been hypothesized to function in a number of cortical developmental processes (Silberberg et al., 2006; Mei and Xiong, 2008). Several recent studies show that the expression of ErbB4 is mainly restricted to GABAergic interneurons (Yau et al., 2003; Woo et al., 2007), specifically, to parvalbumin-positive (PV) fast-spiking (FS) interneurons (Vullhorst et al., 2009; Fazzari et al., 2010), a large majority of which are PV FS basket cells (Kawaguchi, 1995; Taniguchi et al., 2013). However, in the medial prefrontal cortex (mPFC), a brain region that is closely associated with neuropsychiatric disorders including schizophrenia, little is known about the roles of ErbB4 signals during the development of GABAergic circuitry particularly that associated with PV FS basket cells. Here, using molecular genetics, biochemistry, and electrophysiology, we deleted ErbB4 receptors in GABAergic forebrain neurons during the embryonic period and demonstrated that in the mouse mPFC, ErbB4 signals were dispensable for the development of GABAergic synapses by PV FS basket cells. Interestingly, they were required for the final maturation rather than the initial formation of glutamatergic synapses on PV FS basket cells. Furthermore, activity-dependent GABAergic PV FS pyramidal neuron transmission was decreased, whereas activity of pyramidal neurons was increased in KO mice. Together, these data indicate that ErbB4 signals contribute to the development of GABAergic circuitry associated with FS basket cells in component- and stage-dependent manners in the mPFC in vivo, and may suggest a mechanism for neuropsychiatric disorders including schizophrenia.
Assuntos
Receptores ErbB/genética , Interneurônios/metabolismo , Rede Nervosa/metabolismo , Córtex Pré-Frontal/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Receptores ErbB/metabolismo , Camundongos , Camundongos Knockout , Parvalbuminas/metabolismo , Células Piramidais/metabolismo , Receptor ErbB-4 , Sinapses/fisiologia , Transmissão Sináptica/fisiologiaRESUMO
BACKGROUND: Functional imaging studies have indicated that patients with low back pain can have significant reductions in cerebral cortex grey matter. However, the mechanisms governing the nociceptive pathways in the human brain are unclear. The aim of this study was to use functional magnetic resonance imaging (fMRI) and regional homogeneity (ReHo) to investigate changes in resting-state brain activity in subjects that experienced experimentally induced low back pain. METHODS: Healthy subjects (n = 15) underwent fMRI (3.0 T) at baseline and during painful stimulation (intramuscular injection of 3% hypertonic saline). RESULTS: Compared to the scans conducted at baseline, scans conducted during experimentally induced low back pain showed increased ReHo on the right side in the medial prefrontal cortex, precuneus, insula, parahippocampal gyrus and cerebellum (posterior lobe), but decreased ReHo in the primary somatosensory cortex, anterior cingulate cortex and parahippocampal gyrus on the left side. The right inferior parietal lobule also showed a decreased ReHo (P < 0.05, cluster threshold ≥10). CONCLUSIONS: These findings suggest that abnormally spontaneous resting-state activity in some brain regions may be associated with pain processing. These changes in neural activity may contribute to the recognition, execution, memory and emotional processing of acute low back pain.
Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiopatologia , Dor Lombar/fisiopatologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Descanso/fisiologia , Adulto JovemRESUMO
Novel silicone-modified biochar adsorbents (BPS-MBCs) were prepared by utilizing waste black peanut shell (BPS) as a raw biochar and gamma-amino-propyl triethoxysilane (silicone) as an inorganic modifier. The novelty of this work is that the incorporation of silicone into BPS can rise the specific surface area and porosity of BPS-MBCs and elevate their adsorptions for copper (II). Sorption kinetics data for copper (II) were molded using five kinetic equations [i.e. Lagergren 1st-order and 2nd-order, intraparticle diffusion (IN-D), Elovich, and Diffusion-chemisorption]. The equilibrium adsorption data for copper (II) were analyzed using two-parameter isotherm equations [i.e. Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin] and three-parameter Sips, Redlich-Peterson and Toth isotherm models. It was validated that copper (II) sorption on BPS-MBCs matched better with pseudo-2nd-order kinetic, Diffusion-chemisorption and Langmuir isotherm models. The maximal qmLan of BPS-MBC-400 was near 284 mg/g at 45 °C. By multi-phase fitting of IN-D modelling, intra-particle diffusion coefficient (kin-d) and diffusion coefficient of external mass-transfer (DEx-Di) for copper (II) were calculated. The low sorption energy from Temkin and mean free energy from D-R modellings implied that copper (II) sorption was initiated by weak non-covalent bond interactions. Thermodynamic parameters indicated that copper (II) on BPS-MBCs was an endothermic and spontaneous process. Recycling of BPS-MBC-400 for copper (II) suggested it has excellent reusability. The major mechanism of copper (II) on BPS-MBCs is possibly comprised of multiple processes, such as physical adsorption (electrostatic attraction), chemical adsorption (adsorption from functional groups, chelation, and ion exchange) and diffusion-chemisorption. Based on these findings, it is expects that BPS-MBCs are promising sorbents for copper (II) eradication from Cu(II)-including wastewater.
RESUMO
Air pollution can cause disease and has become a major global environmental problem. It is currently believed that air pollution may be related to the progression of SSNHL. As a rapidly developing city in recent years, Hefei has serious air pollution. In order to explore the correlation between meteorological variables and SSNHL admissions, we conducted this study. This study investigated the short-term associations between SSNHL patients admitted to the hospital and Hefei climatic variables. The daily data on SSNHL-related hospital admissions and meteorological variables containing mean temperature (T-mean; °C), diurnal temperature range (DTR; °C), atmospheric pressure (AP; Hp), and relative humidity (RH; %), from 2014 to 2021 (2558 days), were collected. A time-series analysis integrating distributed lag non-linear models and generalized linear models was used. PubMed, Embase, Cochrane Library, and Web of Science databases were searched. Literature published up to August 2023 was reviewed to explore the potential impact mechanisms of meteorological factors on SSNHL. The mechanisms were determined in detail, focusing on wind speed, air pressure, temperature, humidity, and air pollutants. Using a median of 50.00% as a baseline, the effect of exceedingly low T-mean in the single-day hysteresis effect model began at a lag of 8 days (RR = 1.032, 95% CI: 1.001 ~ 1.064). High DTR affected the admission rate for SSNHL on lag 0 day. The significance of the effect was the greatest on that day (RR = 1.054, 95% CI: 1.007 ~ 1.104) and then gradually decreased. High and exceedingly high RH affected the admission rate SSNHL on lag 0 day, and these effects lasted for 8 and 7 days, respectively. There were significant associations between all grades of AP and SSNHL. This is the first study to assess the effect of meteorological variables on SSNHL-related admissions in China using a time-series approach. Long-term exposures to high DTR, RH values, low T-mean values, and all AP grades enhance the incidence of SSNHL in residents. Limiting exposure to extremes of ambient temperature and humidity may reduce the number of SSNHL-related hospital visits in the region. It is advisable to maintain a suitable living environment temperature and avoid extreme temperature fluctuations and high humidity. During periods of high air pollution, it is recommended to stay indoors and refrain from outdoor exercise.
Assuntos
Poluição do Ar , Conceitos Meteorológicos , China/epidemiologia , Humanos , Poluentes Atmosféricos , Perda Auditiva Neurossensorial/epidemiologia , Temperatura , Umidade , Perda Auditiva Súbita/epidemiologiaRESUMO
The mechanisms of anxiety disorders, the most common mental illness, remain incompletely characterized. The ventral hippocampus (vHPC) is critical for the expression of anxiety. However, current studies primarily focus on vHPC neurons, leaving the role for vHPC astrocytes in anxiety largely unexplored. Here, genetically encoded Ca2+ indicator GCaMP6m and in vivo fiber photometry calcium imaging are used to label vHPC astrocytes and monitor their activity, respectively, genetic and chemogenetic approaches to inhibit and activate vHPC astrocytes, respectively, patch-clamp recordings to measure glutamate currents, and behavioral assays to assess anxiety-like behaviors. It is found that vHPC astrocytic activity is increased in anxiogenic environments and by 3-d subacute restraint stress (SRS), a well-validated mouse model of anxiety disorders. Genetic inhibition of vHPC astrocytes exerts anxiolytic effects on both innate and SRS-induced anxiety-related behaviors, whereas hM3Dq-mediated chemogenetic or SRS-induced activation of vHPC astrocytes enhances anxiety-like behaviors, which are reversed by intra-vHPC application of the ionotropic glutamate N-methyl-d-aspartate receptor antagonists. Furthermore, intra-vHPC or systemic application of the N-methyl-d-aspartate receptor antagonist memantine, a U.S. FDA-approved drug for Alzheimer's disease, fully rescues SRS-induced anxiety-like behaviors. The findings highlight vHPC astrocytes as critical regulators of stress and anxiety and as potential therapeutic targets for anxiety and anxiety-related disorders.