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1.
Proc Natl Acad Sci U S A ; 121(35): e2406928121, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39178233

RESUMO

Autism spectrum disorders (ASD) can be caused by environmental factors. These factors act early in the development of the nervous system and induce stereotyped repetitive behaviors and diminished social interactions, among other outcomes. Little is known about how these behaviors are produced. In pregnant women, delivery of valproic acid (VPA) (to control seizure activity or stabilize mood) or immune activation by a virus increases the incidence of ASD in offspring. We found that either VPA or Poly Inosine:Cytosine (which mimics a viral infection), administered at mouse embryonic day 12.5, induced a neurotransmitter switch from GABA to glutamate in PV- and CCK-expressing interneurons in the medial prefrontal cortex by postnatal day 10. The switch was present for only a brief period during early postnatal development, observed in male and female mice at postnatal day 21 and reversed in both males and females by postnatal day 30. At postnatal day 90, male mice exhibited stereotyped repetitive behaviors and diminished social interaction while female mice exhibited only stereotyped repetitive behavior. Transfecting GAD1 in PV- and CCK-expressing interneurons at postnatal day 10, to reintroduce GABA expression, overrode the switch and prevented expression of autistic-like behavior. These findings point to an important role of neurotransmitter switching in mediating the environmental causes of autism.


Assuntos
Ácido Valproico , Ácido gama-Aminobutírico , Animais , Feminino , Camundongos , Masculino , Gravidez , Ácido Valproico/toxicidade , Ácido gama-Aminobutírico/metabolismo , Interneurônios/metabolismo , Animais Recém-Nascidos , Comportamento Animal , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/patologia , Glutamato Descarboxilase/metabolismo , Glutamato Descarboxilase/genética , Transtorno Autístico/etiologia , Transtorno Autístico/metabolismo , Ácido Glutâmico/metabolismo , Neurotransmissores/metabolismo , Poli I-C , Córtex Pré-Frontal/metabolismo , Transtorno do Espectro Autista/metabolismo , Transtorno do Espectro Autista/etiologia , Transtorno do Espectro Autista/patologia , Colecistocinina/metabolismo , Parvalbuminas/metabolismo , Camundongos Endogâmicos C57BL , Comportamento Estereotipado/efeitos dos fármacos
2.
Proc Natl Acad Sci U S A ; 121(15): e2318041121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38568976

RESUMO

Stable matching of neurotransmitters with their receptors is fundamental to synapse function and reliable communication in neural circuits. Presynaptic neurotransmitters regulate the stabilization of postsynaptic transmitter receptors. Whether postsynaptic receptors regulate stabilization of presynaptic transmitters has received less attention. Here, we show that blockade of endogenous postsynaptic acetylcholine receptors (AChR) at the neuromuscular junction destabilizes the cholinergic phenotype in motor neurons and stabilizes an earlier, developmentally transient glutamatergic phenotype. Further, expression of exogenous postsynaptic gamma-aminobutyric acid type A receptors (GABAA receptors) in muscle cells stabilizes an earlier, developmentally transient GABAergic motor neuron phenotype. Both AChR and GABAA receptors are linked to presynaptic neurons through transsynaptic bridges. Knockdown of specific components of these transsynaptic bridges prevents stabilization of the cholinergic or GABAergic phenotypes. Bidirectional communication can enforce a match between transmitter and receptor and ensure the fidelity of synaptic transmission. Our findings suggest a potential role of dysfunctional transmitter receptors in neurological disorders that involve the loss of the presynaptic transmitter.


Assuntos
Receptores Colinérgicos , Sinapses , Sinapses/metabolismo , Receptores Colinérgicos/metabolismo , Transmissão Sináptica/fisiologia , Neurônios Motores/metabolismo , Receptores de GABA-A/metabolismo , Ácido gama-Aminobutírico/metabolismo , Neurotransmissores/metabolismo , Colinérgicos , Receptores Pré-Sinápticos
3.
Syst Parasitol ; 101(3): 33, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647718

RESUMO

The mitochondrial (mt) genome can provide data for phylogenetic analyses and evolutionary biology. Herein, we sequenced and annotated the complete mt genome of Ergasilus anchoratus. This mt genome was 13852 bp long and comprised 13 protein-coding genes (PCGs), 22 tRNAs and 2 rRNAs. All PCGs used the standard ATN start codons and complete TAA/TAG termination codons. A majority of tRNA genes exhibited standard cloverleaf secondary structures, with the exception of one tRNA that lacked the TψC arm (trnC), and three tRNAs that lacked the DHU arm (trnR, trnS1 and trnS2). Phylogenetic analyses conducted using Bayesian inference (BI) and maximum likelihood (ML) methods both supported Ergasilidae as a monophyletic family forming a sister group to Lernaea cyprinacea and Paracyclopina nana. It also supported the monophyly of orders Calanoida, Cyclopoida, and Siphonostomatoida; and the monophyly of families Harpacticidae, Ergasilidae, Diaptomidae, and Calanidae. The gene orders of E. anchoratus and Sinergasilus undulatus were identical, which represents the first instance of two identical gene orders in copepods. More mt genomes are needed to better understand the phylogenetic relationships within Copepoda in the future.


Assuntos
Copépodes , Genoma Mitocondrial , Filogenia , Animais , Genoma Mitocondrial/genética , Copépodes/genética , Copépodes/classificação
4.
J Neurosci ; 40(21): 4078-4089, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32434858

RESUMO

Neurotransmitter switching is a form of brain plasticity in which an environmental stimulus causes neurons to replace one neurotransmitter with another, often resulting in changes in behavior. This raises the possibility of applying a specific environmental stimulus to induce a switch that can enhance a desirable behavior or ameliorate symptoms of a specific pathology. For example, a stimulus inducing an increase in the number of neurons expressing dopamine could treat Parkinson's disease, or one affecting the number expressing serotonin could alleviate depression. This may already be producing successful treatment outcomes without our knowing that transmitter switching is involved, with improvement of motor function through physical activity and cure of seasonal depression with phototherapy. This review presents prospects for future investigation of neurotransmitter switching, considering opportunities and challenges for future research and describing how the investigation of transmitter switching is likely to evolve with new tools, thus reshaping our understanding of both normal brain function and mental illness.


Assuntos
Encéfalo/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Neurotransmissores/fisiologia , Animais
5.
BMC Gastroenterol ; 21(1): 171, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33853536

RESUMO

BACKGROUND: The prevalence of Non-alcoholic fatty liver disease (NAFLD) is increasing and emerging as a global health burden. In addition to environmental factors, numerous studies have shown that genetic factors play an important role in the development of NAFLD. Copy number variation (CNV) as a genetic variation plays an important role in the evaluation of disease susceptibility and genetic differences. The aim of the present study was to assess the contribution of CNV to the evaluation of NAFLD in a Chinese population. METHODS: Genome-wide analysis of CNV was performed using high-density comparative genomic hybridisation microarrays (ACGH). To validate the CNV regions, TaqMan real-time quantitative PCR (qPCR) was utilized. RESULTS: A total of 441 CNVs were identified, including 381 autosomal CNVs and 60 sex chromosome CNVs. By merging overlapping CNVs, a genomic CNV map of NAFLD patients was constructed. A total of 338 autosomal CNVRs were identified, including 275 CNVRs with consistent trends (197 losses and 78 gains) and 63 CNVRs with inconsistent trends. The length of the 338 CNVRs ranged from 5.7 kb to 2.23 Mb, with an average size of 117.44 kb. These CNVRs spanned 39.70 Mb of the genome and accounted for ~ 1.32% of the genome sequence. Through Gene Ontology and genetic pathway analysis, we found evidence that CNVs involving nine genes may be associated with the pathogenesis of NAFLD progression. One of the genes (NLRP4 gene) was selected and verified by quantitative PCR (qPCR) method with large sample size. We found the copy number deletion of NLRP4 was related to the risk of NAFLD. CONCLUSIONS: This study indicate the copy number variation is associated with NAFLD. The copy number deletion of NLRP4 was related to the risk of NAFLD. These results could prove valuable for predicting patients at risk of developing NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Biomarcadores , Hibridização Genômica Comparativa , Variações do Número de Cópias de DNA , Genoma , Humanos , Hepatopatia Gordurosa não Alcoólica/genética , Polimorfismo de Nucleotídeo Único
6.
Proc Natl Acad Sci U S A ; 115(20): 5064-5071, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29686073

RESUMO

Neurotransmitter switching in the adult mammalian brain occurs following photoperiod-induced stress, but the mechanism of regulation is unknown. Here, we demonstrate that elevated activity of dopaminergic neurons in the paraventricular nucleus of the hypothalamus (PaVN) in the adult rat is required for the loss of dopamine expression after long-day photoperiod exposure. The transmitter switch occurs exclusively in PaVN dopaminergic neurons that coexpress vesicular glutamate transporter 2 (VGLUT2), is accompanied by a loss of dopamine type 2 receptors (D2Rs) on corticotrophin-releasing factor (CRF) neurons, and can lead to increased release of CRF. Suppressing activity of all PaVN glutamatergic neurons decreases the number of inhibitory PaVN dopaminergic neurons, indicating homeostatic regulation of transmitter expression in the PaVN.


Assuntos
Encéfalo/metabolismo , Dopamina/metabolismo , Neurônios Dopaminérgicos/fisiologia , Luz , Neurotransmissores/metabolismo , Estresse Fisiológico , Animais , Encéfalo/patologia , Encéfalo/efeitos da radiação , Células Cultivadas , Hormônio Liberador da Corticotropina , Neurônios Dopaminérgicos/citologia , Hipotálamo/metabolismo , Hipotálamo/patologia , Hipotálamo/efeitos da radiação , Masculino , Neurotransmissores/efeitos da radiação , Núcleo Hipotalâmico Paraventricular/metabolismo , Núcleo Hipotalâmico Paraventricular/patologia , Núcleo Hipotalâmico Paraventricular/efeitos da radiação , Ratos , Ratos Long-Evans , Receptores Dopaminérgicos/metabolismo , Proteína Vesicular 2 de Transporte de Glutamato/metabolismo
7.
BMC Gastroenterol ; 20(1): 66, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32164541

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is currently the most common cause of chronic liver disease nowadays. Changes in diet and lifestyle have led to a dramatic increase in the prevalence of NAFLD around the world. This meta-analysis is to investigate the efficacy of physical activity intervention on liver-specific endpoints in the population with NAFLD, including hepatic enzyme, serum lipid, glucose metabolism and intra-hepatic lipid. METHODS: PubMed and China National Knowledge Infrastructure (CNKI) databases were searched for randomized clinical trials of physical activity intervention on NAFLD patients through April 20th, 2019. Effect sizes were reported as standardized mean difference (SMD) and 95% confidence intervals (CI). Quality of included studies was assessed according to the Cochrane risk of bias tool. Meta-analyses were conducted using random-effect or fixed-effect models depending on the significance of heterogeneity. Subgroup analyses according to types and duration of physical activity were conducted to investigate clinical variability. RESULTS: Nine studies with a cumulative total of 951 participants met selection criteria. Physical activity was found associated with small reductions in hepatic enzyme parameters: ALT (SMD -0.17, 95% CI:-0.30 to - 0.05), AST (SMD -0.25, 95% CI: - 0.38, - 0.13) and GGT (SMD -0.22, 95% CI: - 0.36, - 0.08). Significant small improvements were also found in serum lipid parameters including TC (SMD = - 0.22, 95% CI: - 0.34, - 0.09), TG (SMD = - 0.18, 95% CI: - 0.31 to - 0.06) and LDL-C (SMD = - 0.26, 95% CI: - 0.39 to - 0.13). Significant improvement was also found in intra-hepatic lipid content (SMD = - 0.21, 95% CI: - 0.36 to - 0.06) There was no difference between physical intervention group and control group in HDL and three glucose metabolism parameters. Subgroup analysis suggested both aerobic exercise alone and resistance exercise alone can improve most liver function and longer period of exercise generally had better improvement effect. CONCLUSIONS: Our findings suggest that physical activity alone can only slightly improve hepatic enzyme levels, most serum lipid levels and intra-hepatic lipid content in non-diabetic patients with NAFLD.


Assuntos
Terapia por Exercício/métodos , Hepatopatia Gordurosa não Alcoólica/terapia , Glicemia/metabolismo , HDL-Colesterol/sangue , Exercício Físico , Humanos , Metabolismo dos Lipídeos , Lipídeos/sangue , Fígado/enzimologia , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/metabolismo , Ensaios Clínicos Controlados Aleatórios como Assunto , Treinamento Resistido
8.
J Neurosci ; 35(6): 2674-88, 2015 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-25673858

RESUMO

Microglia are the resident immune cells in the CNS and play diverse roles in the maintenance of CNS homeostasis. Recent studies have shown that microglia continually survey the CNS microenvironment and scavenge cell debris and aberrant proteins by phagocytosis and pinocytosis, and that reactive microglia are capable to present antigens to T cells and initiate immune responses. However, how microglia process the endocytosed contents and evoke an immune response remain unclear. Here we report that a size-dependent selective transport of small soluble contents from the pinosomal lumen into lysosomes is critical for the antigen processing in microglia. Using fluorescent probes and water-soluble magnetic nanobeads of defined sizes, we showed in cultured rodent microglia, and in a cell-free reconstructed system that pinocytosed proteins become degraded immediately following pinocytosis and the resulting peptides are selectively delivered to major histocompatibility complex class II (MHC-II) containing lysosomes, whereas undegraded proteins are retained in the pinosomal lumen. This early size-based sorting of pinosomal contents relied on the formation of transient tunnel between pinosomes and lysosomes in a Rab7- and dynamin II-dependent manner, which allowed the small contents to pass through but restricted large ones. Inhibition of the size-based sorting markedly reduced proliferation and cytokine release of cocultured CD4(+) T cells, indicating that the size-based sorting is required for efficient antigen presentation by microglial cells. Together, these findings reveal a novel early sorting mechanism for pinosomal luminal contents in microglial cells, which may explain how microglia efficiently process protein antigens and evoke an immune response.


Assuntos
Microglia/fisiologia , Microglia/ultraestrutura , Pinocitose/fisiologia , Animais , Células Apresentadoras de Antígenos/ultraestrutura , Antígenos/metabolismo , Fusão Celular , Separação Celular , Tamanho Celular , Feminino , Técnicas In Vitro , Lisossomos/metabolismo , Ativação de Macrófagos , Masculino , Camundongos , Cultura Primária de Células , Ratos , Ratos Sprague-Dawley , Receptores de Interleucina-8A/genética
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(8): 2579-84, 2016 Aug.
Artigo em Zh | MEDLINE | ID: mdl-30074368

RESUMO

The heterojunction was formed between two kinds of coupling semiconductors , which improved the charge separation efficiency of system, widened the spectral response range of catalysts and improved photocatalytic propertirs of catalysts. The process of preparation of semiconductors coupling was easily affected by preparation methods and reaction temperature and so on, which would cause the changes in crystal structure and surface properties of coupling semiconductors, thus photocatalytic quantum efficiency of coupling semiconductors was increased. In this article, the following three aspects were mainly discussed. (1) About the coupled system of halogen bismuth oxide and oxide, because generaling BiOX with the semiconductor material compound, the efficient heterojunction structure could be formed, photocatalytic performances of the photocatalytic degradation of pollutants were improved. (2) About the coupled system of AgX and BiOX, compared with the pure AgI or BiOI, composite photocatalytic materials of AgI/BiOI had higher photocatalytic reactivity in visible light. (3) About the coupled system of halogen bismuth oxide and other compounds, after Bi2S3 coupled with BiOX, photoproduction electronic migrated in the two kinds of catalysts, the separation efficiency of electrons and holes was improved, and photocatalytic performances of coupling compound were improved. In addition, in recent years, the latest research progress of the preparation method, the influencing factors of the photocatalytic performance and improving the utilization efficiency of visible light of semiconductors coupling at home and abroad was reviewed in this paper. Finally, the main problems and the future striving direction in semiconductors coupling were presented.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(8): 2333-8, 2015 Aug.
Artigo em Zh | MEDLINE | ID: mdl-26672320

RESUMO

Phosphogypsum, which contains more than 90% of the calcium sulfate dehydrate (CaSO4 · 2H2O), is a kind of important renewable gypsum resources. Unlike the natural gypsum, however, phosphorus, fluorine, organic matter and other harmful impurities in phosphogypsum limit its practical use. To ascertain the existence form, content and phase distribution of trace fluoride in phosphogypsum has important theoretical values in removing trace fluoride effectively. In this present paper, the main existence form and phase distribution of trace fluoride in phosphogypsum was investigated by the combination of X-ray photoelectron spectroscopy (XPS) and Electron microprobe analysis (EMPA). The results show that trace fluoride phase mainly includes NaF, KF, CaF2, K2SiF6, Na2SiF6, Na3AlF6, K3AlF6, AlF3 · 3H2O, AlF2.3(OH)0.7 · H2O, Ca5(PO4)3F, Ca10(PO4)6F2. Among them, 4.83% of fluorine exists in the form of fluoride (NaF, KF, CaF2); Accordingly, 8.43% in the form of fluoride phosphate (Ca5(PO4)3F, Ca10(PO4)6F2); 12.21% in the form of fluorine aluminate (Na3AlF6, K3AlF6); 41.52% in the form of fluorosilicate (K2SiF6, Na2SiF6); 33.02% in the form of aluminum fluoride with crystal water (AlF3 · 3H2O, AlF2.3(OH)0.7 · H2O). In the analysis of phase constitution for trace elements in solid samples, the method of combining XPS and EMPA has more advantages. This study also provides theoretical basis for the removal of trace fluorine impurity and the effective recovery of fluorine resources.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(7): 1997-2000, 2015 Jul.
Artigo em Zh | MEDLINE | ID: mdl-26717766

RESUMO

Using Bi2O3 and MnC2 x 4H2O as raw materials, with HCl as solvent, photocatalysts of Mn-BiOCl with different molar ratio of Mn and Bi were prepared by a hydrolysis method. The obtained samples were characterized by XRD, HRTEM, TEM, UV-Vis DRS and SPS. The UV light photocatalytic activity of Mn-BiOCl was evaluated by using methyl orange as model compounds of photocatalytic reaction. The active species in the degradation process of methyl orange were studied. The results show that the Mn content of Mn-BiOCl photocatalysts has an important effect on the catalytic activity. When the molar ratio of Mn and Bi is 0.25%, the as-prepared Mn-BiOCl photocatalyst has the highest catalytic activity toward the degradation of methyl orange. Photocatalytic degradation rate of methyl orange can reach 95.1%.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(4): 1060-3, 2014 Apr.
Artigo em Zh | MEDLINE | ID: mdl-25007629

RESUMO

UV-Vis absorption spectra and electrochemical properties of 5-(o-hydroxyphenyl)-10, 15, 20-tri-(p-phenyl)porphyrin (TPPOH) and 5-(o-hydroxyphenyl)-10, 15, 20-tri-(p-methoxyphenyl) porphyrin [(p-OCH3)TPPOH] with different electron groups were investigated by experiments and density functional theory (DFT). Due to the introduction of para-methoxyl group (-OCH3), obvious red shift of 3 nm in the maximum absorbance of the UV-Vis spectra, negative shift in redox potential of (p-OCH3)TPPOH, and the decrease (0.06 eV) in the energy gap (DE) of the frontier highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) (of (p-OCH3)TPPOH occurred as compared to those of TPPOH. The results are due to that electron donating groups of -OCH3 increase the electron density of porphyrin ring in (p-OCH3)TPPOH. Electron distributions of the frontier orbital calculated by DFT showed that the increase in the energy levels of HOMO and LUMO, while the decrease of 0.05 eV in the energy gap. The agreement between experimental result and theoretical value and the further illustration of the mechanism for the spectral change and electrochemical properties provide important bases for the design and application of the porphyrin derivatives with different electron groups.

13.
Nat Commun ; 15(1): 8260, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39327428

RESUMO

Cognitive deficits are long-lasting consequences of drug use, yet the convergent mechanism by which classes of drugs with different pharmacological properties cause similar deficits is unclear. We find that both phencyclidine and methamphetamine, despite differing in their targets in the brain, cause the same glutamatergic neurons in the medial prefrontal cortex of male mice to gain a GABAergic phenotype and decrease expression of their glutamatergic phenotype. Suppressing drug-induced gain of GABA with RNA-interference prevents appearance of memory deficits. Stimulation of dopaminergic neurons in the ventral tegmental area is necessary and sufficient to produce this gain of GABA. Drug-induced prefrontal hyperactivity drives this change in transmitter identity. Returning prefrontal activity to baseline, chemogenetically or with clozapine, reverses the change in transmitter phenotype and rescues the associated memory deficits. This work reveals a shared and reversible mechanism that regulates the appearance of cognitive deficits upon exposure to different drugs.


Assuntos
Metanfetamina , Fenciclidina , Córtex Pré-Frontal , Área Tegmentar Ventral , Ácido gama-Aminobutírico , Animais , Masculino , Metanfetamina/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Camundongos , Fenciclidina/farmacologia , Área Tegmentar Ventral/efeitos dos fármacos , Área Tegmentar Ventral/metabolismo , Ácido gama-Aminobutírico/metabolismo , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/metabolismo , Camundongos Endogâmicos C57BL , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Neurônios GABAérgicos/metabolismo , Neurônios GABAérgicos/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Clozapina/farmacologia , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/metabolismo
14.
Front Surg ; 11: 1278421, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38486794

RESUMO

Calcium sulfate and calcium sulfate-based biomaterials have been widely used in non-load-bearing bone defects for hundreds of years due to their superior biocompatibility, biodegradability, and non-toxicity. However, lower compressive strength and rapid degradation rate are the main limitations in clinical applications. Excessive absorption causes a sharp increase in sulfate ion and calcium ion concentrations around the bone defect site, resulting in delayed wound healing and hypercalcemia. In addition, the space between calcium sulfate and the host bone, resulting from excessively rapid absorption, has adverse effects on bone healing or fusion techniques. This issue has been recognized and addressed. The lack of sufficient mechanical strength makes it challenging to use calcium sulfate and calcium sulfate-based biomaterials in load-bearing areas. To overcome these defects, the introduction of various inorganic additives, such as calcium carbonate, calcium phosphate, and calcium silicate, into calcium sulfate is an effective measure. Inorganic materials with different physical and chemical properties can greatly improve the properties of calcium sulfate composites. For example, the hydrolysis products of calcium carbonate are alkaline substances that can buffer the acidic environment caused by the degradation of calcium sulfate; calcium phosphate has poor degradation, which can effectively avoid the excessive absorption of calcium sulfate; and calcium silicate can promote the compressive strength and stimulate new bone formation. The purpose of this review is to review the poor properties of calcium sulfate and its complications in clinical application and to explore the effect of various inorganic additives on the physicochemical properties and biological properties of calcium sulfate.

15.
Science ; 383(6688): 1252-1259, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38484078

RESUMO

Overgeneralization of fear to harmless situations is a core feature of anxiety disorders resulting from acute stress, yet the mechanisms by which fear becomes generalized are poorly understood. In this study, we show that generalized fear in mice results from a transmitter switch from glutamate to γ-aminobutyric acid (GABA) in serotonergic neurons of the lateral wings of the dorsal raphe. Similar change in transmitter identity was found in the postmortem brains of individuals with posttraumatic stress disorder (PTSD). Overriding the transmitter switch in mice prevented the acquisition of generalized fear. Corticosterone release and activation of glucocorticoid receptors mediated the switch, and prompt antidepressant treatment blocked the cotransmitter switch and generalized fear. Our results provide important insight into the mechanisms involved in fear generalization.


Assuntos
Encéfalo , Medo , Generalização da Resposta , Ácido Glutâmico , Transtornos de Estresse Pós-Traumáticos , Estresse Psicológico , Ácido gama-Aminobutírico , Animais , Camundongos , Encéfalo/metabolismo , Medo/fisiologia , Ácido gama-Aminobutírico/metabolismo , Neurônios/metabolismo , Transtornos de Estresse Pós-Traumáticos/metabolismo , Estresse Psicológico/metabolismo , Ácido Glutâmico/metabolismo , Corticosterona/metabolismo , Receptores de Glucocorticoides/metabolismo , Humanos
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(3): 628-31, 2013 Mar.
Artigo em Zh | MEDLINE | ID: mdl-23705421

RESUMO

Nano-rutile TiO2 photocatalysts with bigger specific surface area were prepared by a hydrolysis method at 323 K, and characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), ultraviolet-visible diffuse reflection spectroscopy (UV-Vis DRS), infrared spectroscopy (IR) and photoelectrochemical (PEC). The ultraviolet (UV) and visible light photocatalytic activities of as-prepared rutile and anatase TiO2 nano-photocatalysts with almost same specific surface areas were evaluated by methyl orange (MO) as mode compound to photocatalytic reaction. The results of the photocatalytic experiment shows that when rutile and anatase have the similar specific surface area of approximately 95 m2.g-1, the UV light photocatalytic activity of rutile is comparable to that of anatase, while rutile shows significantly higher visible light photocatalytic activities than anatase. The photoelectrochemical experiment shows that the order of photocurrent densities of the catalysts from weak to strong is in accordance with the order of UV light photocatalytic activities of the catalysts from low to high under UV light irradiation.

17.
Res Sq ; 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38168375

RESUMO

Cognitive deficits are a long-lasting consequence of drug use, yet the convergent mechanism by which classes of drugs with different pharmacological properties cause similar deficits is unclear. We find that both phencyclidine and methamphetamine, despite differing in their targets in the brain, cause the same glutamatergic neurons in the medial prefrontal cortex to gain a GABAergic phenotype and decrease their expression of the vesicular glutamate transporter. Suppressing the drug-induced gain of GABA with RNA-interference prevents the appearance of memory deficits. Stimulation of dopaminergic neurons in the ventral tegmental area is necessary and sufficient to produce this gain of GABA. Drug-induced prefrontal hyperactivity drives this change in transmitter identity. Returning prefrontal activity to baseline, chemogenetically or with clozapine, reverses the change in transmitter phenotype and rescues the associated memory deficits. The results reveal a shared and reversible mechanism that regulates the appearance of cognitive deficits upon exposure to different drugs.

18.
bioRxiv ; 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37214936

RESUMO

Overgeneralization of fear to harmless situations is a core feature of anxiety disorders resulting from acute stress, yet the mechanisms by which fear becomes generalized are poorly understood. Here we show that generalized fear in mice in response to footshock results from a transmitter switch from glutamate to GABA in serotonergic neurons of the lateral wings of the dorsal raphe. We observe a similar change in transmitter identity in the postmortem brains of PTSD patients. Overriding the transmitter switch in mice using viral tools prevents the acquisition of generalized fear. Corticosterone release and activation of glucocorticoid receptors trigger the switch, and prompt antidepressant treatment blocks the co-transmitter switch and generalized fear. Our results provide new understanding of the plasticity involved in fear generalization.

19.
Anal Chim Acta ; 1189: 339208, 2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-34815044

RESUMO

The electrochemical method for highly sensitive determination of arsenic(III) in real water samples with noble-metal-free nanomaterials is still a difficult but significant task. Here, an electrochemical sensor driven by noble-metal-free layered porous Fe3O4/Co3S4 nanosheets was successfully employed for As(III) analysis, which was prepared via a facile two-step method involves a hydrothermal treatment and a subsequent sulfurization process. As expected, the electrochemical detection of As(III) in 0.1 M HAc-NaAc (pH 6.0) by square wave anodic stripping voltammetry (SWASV) with a considerable sensitivity of 4.359 µA/µg·L-1 was obtained, which is better than the commonly used noble metals modified electrodes. Experimental and characterization results elucidate the enhancement of As(III) electrochemical performance could be attributed to its nano-porous structure, the presence of oxygen vacancies and strong synergetic coupling effects between Fe3O4 and Co3S4 species. Besides, the Fe3O4/Co3S4 modified screen printed carbon electrode (Fe3O4/Co3S4-SPCE) shows remarkable stability and repeatability, valuable anti-interference ability and could be used for detection in real water samples. Consequently, the results confirm that as-prepared porous Fe3O4/Co3S4 nanosheets is identified as a promising modifier to detect As(III) in real sample analysis.


Assuntos
Técnicas Eletroquímicas , Oxigênio , Carbono , Eletrodos , Ouro
20.
Sci Rep ; 11(1): 13984, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234263

RESUMO

A recent genome-wide copy number variations (CNVs) scan identified a 16q12.2 deletion that included the carboxylesterase 1 (CES1) gene, which is important in the metabolism of fatty acids and cholesterol. We aimed to investigate whether CES1 CNVs was associated with susceptibility to non-alcoholic fatty liver disease (NAFLD) in a Chinese Han population. A case-control study was conducted among 303 patients diagnosed with NAFLD and 303 age (± 5) and sex-matched controls from the Affiliated Nanping First Hospital of Fujian Medical University in China. The copy numbers of CES1 were measured using TaqMan quantitative real-time polymerase chain reaction (qPCR) and serum CES1 was measured using enzyme-linked immunosorbent assays. The Chi-squared test and a logistic regression model were used to evaluate the association between CES1 CNVs and NAFLD susceptibility. The distribution of CES1 CNVs showed a higher frequency of CNVs loss (< 2) among patients; however, the difference was not significant (P = 0.05). After controlling for other known or suspected risk factors for NAFLD, CES1 CNVs loss was significantly associated with greater risk of NAFLD (adjusted OR = 2.75, 95% CI 1.30-5.85, P = 0.01); while CES1 CNVs gain (> 2) was not. There was a suggestion of an association between increased CES1 serum protein levels and CNVs losses among cases, although this was not statistically significant (P = 0.07). Copy number losses (< 2) of CES1 contribute to susceptibility to NAFLD in the Chinese Han population.


Assuntos
Povo Asiático/genética , Hidrolases de Éster Carboxílico/genética , Variações do Número de Cópias de DNA , Predisposição Genética para Doença , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/etiologia , Adulto , Idoso , Biomarcadores , Hidrolases de Éster Carboxílico/sangue , Estudos de Casos e Controles , China/epidemiologia , Feminino , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/metabolismo , Medição de Risco , Adulto Jovem
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