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1.
Chem Rev ; 123(19): 11230-11268, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37589590

RESUMO

Polymorphic 2D materials allow structural and electronic phase engineering, which can be used to realize energy-efficient, cost-effective, and scalable device applications. The phase engineering covers not only conventional structural and metal-insulator transitions but also magnetic states, strongly correlated band structures, and topological phases in rich 2D materials. The methods used for the local phase engineering of 2D materials include various optical, geometrical, and chemical processes as well as traditional thermodynamic approaches. In this Review, we survey the precise manipulation of local phases and phase patterning of 2D materials, particularly with ideal and versatile phase interfaces for electronic and energy device applications. Polymorphic 2D materials and diverse quantum materials with their layered, vertical, and lateral geometries are discussed with an emphasis on the role and use of their phase interfaces. Various phase interfaces have demonstrated superior and unique performance in electronic and energy devices. The phase patterning leads to novel homo- and heterojunction structures of 2D materials with low-dimensional phase boundaries, which highlights their potential for technological breakthroughs in future electronic, quantum, and energy devices. Accordingly, we encourage researchers to investigate and exploit phase patterning in emerging 2D materials.

2.
J Transl Med ; 21(1): 414, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37365600

RESUMO

BACKGROUND: Enumeration of circulating tumor cells (CTCs) has proven clinical significance for monitoring patients with metastatic cancers. Multiplexed gene expression profiling of CTCs is a potential tool for assessing disease status and monitoring treatment response. The Parsortix® technology enables the capture and harvest of CTCs from blood based on cell size and deformability. The HyCEAD™ (Hybrid Capture Enrichment Amplification and Detection) assay enables simultaneous amplification of short amplicons for up to 100 mRNA targets, and the Ziplex™ instrument quantifies the amplicons for highly sensitive gene expression profiling down to single cell levels. The aim of the study was to functionally assess this system. METHODS: The HyCEAD/Ziplex platform was used to quantify the expression levels for 72 genes using as little as 20 pg of total RNA or a single cultured tumor cell. Assay performance was evaluated using cells or total RNA spiked into Parsortix harvests of healthy donor blood. The assay was also evaluated using total RNA obtained from Parsortix harvests of blood from metastatic breast cancer (MBC) patients or healthy volunteers (HVs). RESULTS: Using genes with low expression in WBC RNA and/or in unspiked Parsortix harvests from HVs, the assay distinguished between the different breast cancer and ovarian cancer cell lines with as little as 20 pg of total RNA (equivalent to a single cell) in the presence of 1 ng of WBC RNA. Single cultured cells spiked into Parsortix harvests from 10 mL of HV blood were also detected and distinguished from each other. CVs from repeatability experiments were less than 20%. Hierarchical clustering of clinical samples differentiated most MBC patients from HVs. CONCLUSION: HyCEAD/Ziplex provided sensitive quantification of expression of 72 genes from 20 pg of total RNA from cultured tumor cell lines or from single cultured tumor cells spiked into lysates from Parsortix harvests of HV blood. The HyCEAD/Ziplex platform enables the quantification of selected genes in the presence of residual nucleated blood cells in Parsortix harvests. The HyCEAD/Ziplex platform is an effective tool for multiplexed molecular characterization of mRNA in small numbers of tumor cells harvested from blood.


Assuntos
Neoplasias da Mama , Células Neoplásicas Circulantes , Humanos , Feminino , Células Neoplásicas Circulantes/patologia , Neoplasias da Mama/patologia , Perfilação da Expressão Gênica , RNA Mensageiro/metabolismo , RNA , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo
3.
J Biol Chem ; 294(46): 17487-17500, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31586032

RESUMO

The DNA-binding protein PU.1 is a myeloid lineage-determining and pioneering transcription factor due to its ability to bind "closed" genomic sites and maintain "open" chromatin state for myeloid lineage-specific genes. The precise mechanism of PU.1 in cell type-specific programming is yet to be elucidated. The melanoma cell line B16BL6, although it is nonmyeloid lineage, expressed Toll-like receptors and activated the transcription factor NF-κB upon stimulation by the bacterial cell wall component lipopolysaccharide. However, it did not produce cytokines, such as IL-1ß mRNA. Ectopic PU.1 expression induced remodeling of a novel distal enhancer (located ∼10 kbp upstream of the IL-1ß transcription start site), marked by nucleosome depletion, enhancer-promoter looping, and histone H3 lysine 27 acetylation (H3K27ac). PU.1 induced enhancer-promoter looping and H3K27ac through two distinct PU.1 regions. These PU.1-dependent events were independently required for subsequent signal-dependent and co-dependent events: NF-κB recruitment and further H3K27ac, both of which were required for enhancer RNA (eRNA) transcription. In murine macrophage RAW264.7 cells, these PU.1-dependent events were constitutively established and readily expressed eRNA and subsequently IL-1ß mRNA by lipopolysaccharide stimulation. In summary, this study showed a sequence of epigenetic events in programming IL-1ß transcription by the distal enhancer priming and eRNA production mediated by PU.1 and the signal-dependent transcription factor NF-κB.


Assuntos
Interleucina-1beta/genética , Melanoma Experimental/genética , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/genética , Transativadores/genética , Animais , Linhagem Celular Tumoral , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Camundongos , Regiões Promotoras Genéticas , Células RAW 264.7 , Ativação Transcricional
4.
Mol Med ; 26(1): 75, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32736525

RESUMO

BACKGROUND: Therapeutic lymphangiogenesis in an orthotopic lung transplant model has been shown to improve acute allograft rejection that is mediated at least in part through hyaluronan drainage. Lymphatic vessel endothelial hyaluronan receptor (LYVE-1) expressed on the surface of lymphatic endothelial cells plays important roles in hyaluronan uptake. The impact of current immunosuppressive therapies on lung lymphatic endothelial cells is largely unknown. We tested the hypothesis that FK506, the most commonly used immunosuppressant after lung transplantation, induces lung lymphatic endothelial cell dysfunction. METHODS: Lung lymphatic endothelial cells were cultured in vitro and treated with FK506. Telomerase activity was measured using the TRAP assay. Protein expression of LYVE-1 and senescence markers p21 and ß-galactosidase was assessed with western blotting. Matrigel tubulation assay were used to investigate the effects of FK506 on TNF-α-induced lymphangiogenesis. Dual luciferase reporter assay was used to confirm NFAT-dependent transcriptional regulation of LYVE-1. Flow cytometry was used to examine the effects of FK506 on LYVE-1 in precision-cut-lung-slices ex vivo and on hyaluronan uptake in vitro. RESULTS: In vitro, FK506 downregulated telomerase reverse transcriptase expression, resulting in decreased telomerase activity and subsequent induction of p21 expression and cell senescence. Treatment with FK506 decreased LYVE-1 mRNA and protein levels and resulted in decreased LEC HA uptake. Similar result showing reduction of LYVE-1 expression when treated with FK506 was observed ex vivo. We identified a putative NFAT binding site on the LYVE-1 promoter and cloned this region of the promoter in a luciferase-based reporter construct. We showed that this NFAT binding site regulates LYVE-1 transcription, and mutation of this binding site blunted FK506-dependent downregulation of LYVE-1 promoter-dependent transcription. Finally, FK506-treated lymphatic endothelial cells show a blunted response to TNF-α-mediated lymphangiogenesis. CONCLUSION: FK506 alters lymphatic endothelial cell molecular characteristics and causes lymphatic endothelial cell dysfunction in vitro and ex vivo. These effects of FK506 on lymphatic endothelial cell may impair the ability of the transplanted lung to drain hyaluronan macromolecules in vivo. The implications of our findings on the long-term health of lung allografts merit more investigation.


Assuntos
Senescência Celular/efeitos dos fármacos , Senescência Celular/genética , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Ácido Hialurônico/metabolismo , Tacrolimo/farmacologia , Proteínas de Transporte Vesicular/genética , Animais , Transporte Biológico , Células Cultivadas , Humanos , Linfangiogênese/efeitos dos fármacos , Linfangiogênese/genética , Camundongos , Fatores de Transcrição NFATC/metabolismo , Ligação Proteica , Telomerase/genética , Telomerase/metabolismo , Proteínas de Transporte Vesicular/metabolismo
5.
Mol Pain ; 14: 1744806918812636, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30355052

RESUMO

BACKGROUND: We have previously reported that histamine-induced pruritus was attenuated in toll-like receptor 4 (TLR4) knockout mice due to decreased transient receptor potential V1 (TRPV1) sensitivity. Our results implied that TLR4 potentiated TRPV1 activation in sensory neurons; however, the molecular mechanism has yet to be elucidated. In this study, we investigated the molecular mechanisms of TLR4-mediated TRPV1 potentiation using TLR4-deficient sensory neurons and a heterologous expression system. METHODS: Primary sensory neurons were obtained from wild-type or TLR4 knockout mice, and HEK293T cells expressing TRPV1 and TLR4 were prepared by transient transfection. TRPV1 activity was analyzed by calcium imaging, fluorophotometry, and patch-clamp recording. Subcellular protein distribution was tested by immunocytochemistry and cell surface biotinylation assay. Protein interaction was assessed by western blot and immunoprecipitation assay. RESULTS: Direct association between TRPV1 and TLR4 was detected in HEK293T cells upon heterologous TRPV1 and TLR4 expression. In an immunoprecipitation assay using TLR4-deletion mutants and soluble toll/interleukin-1 receptor (TIR) protein, the cytoplasmic TIR domain of TLR4 was required for TLR4-TRPV1 association and TRPV1 potentiation. In TLR4-deficient sensory neurons, the activation-induced desensitization of TRPV1 increased, accompanied by enhanced TRPV1 clearance from the cell membrane upon activation compared to wild-type neurons. In addition, heterologous TLR4 expression inhibited activation-induced TRPV1 endocytosis and lysosomal degradation in HEK293T cells. CONCLUSION: Our data show that direct association between TRPV1 and TLR4 through the TIR domain enhances TRPV1 activity by blocking activation-induced TRPV1 desensitization.


Assuntos
Células Receptoras Sensoriais/metabolismo , Canais de Cátion TRPV/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Cálcio/metabolismo , Células HEK293 , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/metabolismo , Transdução de Sinais/genética , Canais de Cátion TRPV/genética , Receptor 4 Toll-Like/genética
6.
BMC Complement Altern Med ; 16: 66, 2016 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-26887326

RESUMO

BACKGROUND: Ginseng (Panax ginseng C.A. Meyer) has been used as a traditional herb in the treatment of many medical disorders. Ginsenosides, which are triterpene derivatives that contain sugar moieties, are the main pharmacological ingredients in ginseng. This study was designed to investigate the effect of ginsenoside Rg3-enriched ginseng extract (Rg3GE) on scopolamine-induced memory impairment in mice. METHODS: Rg3GE (50 and 100 mg/kg) were administered to C57BL/6 mice by oral gavage for 14 days (days 1-14). Memory impairment was induced by scopolamine (1 mg/kg, intraperitoneal injection) for 6 days (days 914). The Morris water maze test was used to assess hippocampus-dependent spatial memory. The effects of scopolamine with or without Rg3GE on acetylcholinesterase and nuclear factor-κB (NF-κB) in the hippocampus were also examined. RESULTS: Mice with scopolamine treatment alone showed impairments in the acquisition and retention of spatial memory. Mice that received Rg3GE and scopolamine showed no scopolamine-induced impairment in the acquisition of spatial memory. Oral administration of Rg3GE suppressed the scopolamine-mediated increase in acetylcholinesterase activity and stimulation of the NF-κB pathway (i.e., phosphorylation of p65) in the hippocampus. CONCLUSION: These findings suggest that Rg3GE may stabilize scopolamine-induced memory deficits through the inhibition of acetylcholinesterase activity and NF-κB signaling in the hippocampus.


Assuntos
Ginsenosídeos/uso terapêutico , Transtornos da Memória/tratamento farmacológico , Panax , Extratos Vegetais/uso terapêutico , Animais , Deficiências da Aprendizagem/induzido quimicamente , Deficiências da Aprendizagem/tratamento farmacológico , Masculino , Transtornos da Memória/induzido quimicamente , Camundongos , Camundongos Endogâmicos C57BL , Escopolamina
7.
J Esthet Restor Dent ; 27(6): 374-82, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26031932

RESUMO

PURPOSE: To determine the effects of bleach on dentin fatigue resistance and flexural strength. MATERIALS AND METHODS: Eighty bovine dentin specimens (2 × 2 × 17 mm) were treated with: placebo or 10% carbamide peroxide bleach. Treatment was applied for 6 hours/day for 2 or 8 weeks. After treatment, 10 specimens per group were subjected to fatigue testing (10(6) cycles) whereas the other 10 were stored in artificial saliva as fatigue controls. The specimens undergoing fatigue were checked daily for visible signs of fracture and excluded from subsequent flexural strength tests if fractured. Fatigue control and surviving fatigued specimens were subjected to flexural strength testing. Chi-square, Kruskal-Wallis, factorial analysis of variance (p < 0.05) and Mann-Whitney (p < 0.002) tests were performed. RESULTS: There were significant differences in fatigue resistance (p = 0.003) and flexural strength rank scores (p < 0.0001) among the groups. None of the specimens in the "8-week bleach" group survived the fatigue testing. Fatigue (p = 0.005) and interaction of time and treatment (p = 0.039) were significant factors in the flexural strength results. Fatigued specimens had lower flexural strength than nonfatigued and "8-week bleach" had lower flexural strength than placebo and "2-week bleach" groups. CONCLUSIONS: Prolonged direct bleaching of bovine dentin reduces its fatigue resistance and flexural strength in vitro. Further research is needed in this area. CLINICAL SIGNIFICANCE: It remains prudent to advise patients to limit their exposure to tooth bleaching materials by avoiding direct application of bleach to exposed dentin and by minimizing the duration of bleach treatment.


Assuntos
Dentina , Clareamento Dental/métodos , Animais , Bovinos , Análise do Estresse Dentário
8.
Adv Mater ; : e2402040, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38798189

RESUMO

Topological quantum phases are largely understood in weakly correlated systems, which have identified various quantum phenomena, such as the spin Hall effect, protected transport of helical fermions, and topological superconductivity. Robust ferromagnetic order in correlated topological materials particularly attracts attention, as it can provide a versatile platform for novel quantum devices. Here, a singular Hall response arising from a unique band structure of flat topological nodal lines in combination with electron correlation in a van der Waals ferromagnetic semimetal, Fe3GaTe2, with a high Curie temperature of Tc = 347 K is reported. High anomalous Hall conductivity violating the conventional scaling, resistivity upturn at low temperature, and a large Sommerfeld coefficient are observed in Fe3GaTe2, which implies heavy fermion features in this ferromagnetic topological material. The scanning tunneling microscopy, circular dichroism in angle-resolved photoemission spectroscopy, and theoretical calculations support the original electronic features of the material. Thus, low-dimensional Fe3GaTe2 with electronic correlation, topology, and room-temperature ferromagnetic order appears to be a promising candidate for robust quantum devices.

9.
Nat Neurosci ; 26(9): 1541-1554, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37563296

RESUMO

Social hierarchy is established as an outcome of individual social behaviors, such as dominance behavior during long-term interactions with others. Astrocytes are implicated in optimizing the balance between excitatory and inhibitory (E/I) neuronal activity, which may influence social behavior. However, the contribution of astrocytes in the prefrontal cortex to dominance behavior is unclear. Here we show that dorsomedial prefrontal cortical (dmPFC) astrocytes modulate E/I balance and dominance behavior in adult male mice using in vivo fiber photometry and two-photon microscopy. Optogenetic and chemogenetic activation or inhibition of dmPFC astrocytes show that astrocytes bidirectionally control male mouse dominance behavior, affecting social rank. Dominant and subordinate male mice present distinct prefrontal synaptic E/I balance, regulated by astrocyte activity. Mechanistically, we show that dmPFC astrocytes control cortical E/I balance by simultaneously enhancing presynaptic-excitatory and reducing postsynaptic-inhibitory transmission via astrocyte-derived glutamate and ATP release, respectively. Our findings show how dmPFC astrocyte-neuron communication can be involved in the establishment of social hierarchy in adult male mice.


Assuntos
Astrócitos , Sinapses , Camundongos , Animais , Masculino , Sinapses/fisiologia , Astrócitos/fisiologia , Neurônios/fisiologia , Córtex Pré-Frontal , Transmissão Sináptica/fisiologia
10.
Sci Rep ; 12(1): 5496, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361832

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is accompanied by chronic neurological sequelae such as cognitive decline and mood disorder, but the underlying mechanisms have not yet been elucidated. We explored the possibility that the brain-infiltrating SARS-CoV-2 spike protein contributes to the development of neurological symptoms observed in COVID-19 patients in this study. Our behavioral study showed that administration of SARS-CoV-2 spike protein S1 subunit (S1 protein) to mouse hippocampus induced cognitive deficit and anxiety-like behavior in vivo. These neurological symptoms were accompanied by neuronal cell death in the dorsal and ventral hippocampus as well as glial cell activation. Interestingly, the S1 protein did not directly induce hippocampal cell death in vitro. Rather, it exerted neurotoxicity via glial cell activation, partially through interleukin-1ß induction. In conclusion, our data suggest a novel pathogenic mechanism for the COVID-19-associated neurological symptoms that involves glia activation and non-cell autonomous hippocampal neuronal death by the brain-infiltrating S1 protein.


Assuntos
COVID-19 , Disfunção Cognitiva , Animais , Anticorpos Antivirais/metabolismo , Ansiedade , Morte Celular , Cognição , Disfunção Cognitiva/etiologia , Hipocampo/metabolismo , Humanos , Glicoproteínas de Membrana/metabolismo , Camundongos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/metabolismo , Proteínas do Envelope Viral/metabolismo
11.
Nat Commun ; 13(1): 6536, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36344520

RESUMO

Astrocytes can affect animal behavior by regulating tripartite synaptic transmission, yet their influence on affective behavior remains largely unclear. Here we showed that hippocampal astrocyte calcium activity reflects mouse affective state during virtual elevated plus maze test using two-photon calcium imaging in vivo. Furthermore, optogenetic hippocampal astrocyte activation elevating intracellular calcium induced anxiolytic behaviors in astrocyte-specific channelrhodopsin 2 (ChR2) transgenic mice (hGFAP-ChR2 mice). As underlying mechanisms, we found ATP released from the activated hippocampal astrocytes increased excitatory synaptic transmission in dentate gyrus (DG) granule cells, which exerted anxiolytic effects. Our data uncover a role of hippocampal astrocytes in modulating mice anxiety-like behaviors by regulating ATP-mediated synaptic homeostasis in hippocampal DG granule cells. Thus, manipulating hippocampal astrocytes activity can be a therapeutic strategy to treat anxiety.


Assuntos
Astrócitos , Cálcio , Animais , Camundongos , Astrócitos/metabolismo , Cálcio/metabolismo , Hipocampo/metabolismo , Channelrhodopsins/genética , Camundongos Transgênicos , Trifosfato de Adenosina/farmacologia , Ansiedade
12.
Inj Prev ; 17(5): 291-6, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21622932

RESUMO

UNLABELLED: BACKGROUND STUDIES: on the cost of injury are useful in setting research and policy priorities and it is valuable to observe differences in the economic burden of injuries across countries. OBJECTIVE: To estimate the treated prevalence rate, economic burden and gender- and age-specific costs of injuries in Korea in 2006. DESIGN: Annual direct healthcare costs associated with injuries were estimated from the National Health Insurance, Medical Aid and Automobile Insurance databases. Annual direct non-health costs were estimated for transport and caregiver's costs. Indirect costs were estimated for premature death, absence from work and disability. Costs were adjusted to 2006 levels using the healthcare component of the Consumer Price Index. MAIN OUTCOME MEASURES: Prevalence-based direct costs, incidence-based indirect costs and total costs for injuries, stratified by gender, age group and type of injury. RESULTS: The treated prevalence rate of injury in 2006 of the Korean population was 26.5 per 100, resulting in an annual economic burden of $39837 million ($4703 million in direct and $35134 million in indirect costs). The cost of medical treatment associated with injuries accounted for 9.5% of the total health expenditure in Korea. The cost of premature death was the largest contributor to the total and automobile-related injuries accounted for 30.3% of total costs. CONCLUSIONS: The estimates were considerably understated because they did not include losses in household production and quality of life. Nevertheless, the size and main components of the injury burden were identified; this information should aid decision-making about research priorities and improve monitoring of the effects of policy initiatives.


Assuntos
Efeitos Psicossociais da Doença , Custos de Cuidados de Saúde/estatística & dados numéricos , Ferimentos e Lesões/economia , Acidentes de Trânsito/economia , Acidentes de Trânsito/estatística & dados numéricos , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Custos e Análise de Custo , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Mortalidade Prematura , Prevalência , República da Coreia/epidemiologia , Distribuição por Sexo , Ferimentos e Lesões/epidemiologia , Adulto Jovem
13.
Health Policy ; 89(2): 174-83, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18619703

RESUMO

OBJECTIVE: To assess the extent of consumer use of publicly released hospital performance information by the National Health Evaluation Program (HEP) in Korea. DESIGN: A questionnaire survey with 385 outpatients visiting four general hospitals in Seoul. MAIN OUTCOME MEASURES: The consumer use of performance information was assessed by the consumers' intention to: (1) recommend hospitals with good performance reports, according to HEP, to their relatives; (2) switch to other hospitals with a better performance and (3) keep the performance report for future use. RESULTS: Overall, 52-75% of the respondents expressed their intention to use the hospital performance information. Logistic regression analysis results showed that people would use the performance information if they considered HEP to be effective in improving the quality of health care and the performance reports to be trustworthy and useful in choosing hospitals. CONCLUSION: This study provides evidence that consumers in a health care system with few restrictions for provider choice, such as in Korea, have a high potential to utilize the provider performance information in their decision making. If public use of the performance information becomes common, policy makers should acknowledge the critical value of the quality of the performance report in order to avoid misleading consumers.


Assuntos
Comportamento de Escolha , Participação da Comunidade , Hospitais/normas , Disseminação de Informação , Qualidade da Assistência à Saúde , Adulto , Feminino , Humanos , Coreia (Geográfico) , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
14.
Front Neurosci ; 13: 213, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30949019

RESUMO

A growing body of evidence from both clinical and animal studies indicates that chronic neuropathic pain is associated with comorbid affective disorders. Spinal cord microglial activation is involved in nerve injury-induced pain hypersensitivity characterizing neuropathic pain. However, there is a lack of thorough assessments of microglial activation in the brain after nerve injury. In the present study, we characterized microglial activation in brain sub-regions of CX3CR1GFP/+ mice after chronic constriction injury (CCI) of the sciatic nerve, including observations at delayed time points when affective brain dysfunctions such as depressive-like behaviors typically develop. Mice manifested chronic mechanical hypersensitivity immediately after CCI and developed depressive-like behaviors 8 weeks post-injury. Concurrently, significant increases of soma size and microglial cell number were observed in the medial prefrontal cortex (mPFC), hippocampus, and amygdala 8 weeks post-injury. Transcripts of CD11b, and TNF-α, genes associated with microglial activation or depressive-like behaviors, are correspondingly upregulated in these brain areas. Our results demonstrate that microglia are activated in specific brain sub-regions after CCI at delayed time points and imply that brain microglial activation plays a role in chronic pain-associated affective disorders.

15.
Front Behav Neurosci ; 13: 11, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30760989

RESUMO

The participation of the prefrontal cortex (PFC), hippocampus, and dorsal striatum in switching the learning task from cued to place learning were examined in C57BL/6 and DBA/2 mice, by assessing changed levels of phosphorylated CREB (pCREB). Mice of both strains first received cued training in a water maze for 4 days (4 trials per day), and were then assigned to one of four groups, one with no place training, and three with different durations of place training (2, 4, or 8 days). Both strains showed equal performance in cued training. After the switch to place training, C57BL/6 mice with 2 or 4 days of training performed significantly better than DBA/2 mice, but their superiority disappeared during the second half of an 8 days-place training period. The pCREB levels of these mice were measured 30 min after place training and compared with those of mice that received only cued training. Changes in pCREB levels of C57BL/6 mice were greater in the hippocampal CA3, hippocampal dentate gyrus, orbitofrontal and medial PFC than those of DBA/2 mice, when mice of both received the switched place training for 2 days. We further investigated the roles of orbitofrontal and medial PFC among these brain regions showing strain differences, by destroying each region using selective neurotoxins. C57BL/6 mice with orbitofrontal lesions were slower to acquire the place learning and continued to use the cued search acquired during the cued training phase. These findings indicate that mouse orbitofrontal cortex (OFC) pCREB is associated with behavioral flexibility such as the ability to switch a learning task.

16.
PLoS One ; 14(4): e0213831, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30964887

RESUMO

Lymphatic vessels play an important role in health and in disease. In this study, we evaluated the effects of GSK3-ß inhibition on lung lymphatic endothelial cells in vitro. Pharmacological inhibition and silencing of GSK3-ß resulted in increased lymphangiogenesis of lung lymphatic endothelial cells. To investigate mechanisms of GSK3-ß-mediated lymphangiogenesis, we interrogated the mammalian/mechanistic target of rapamycin pathway and found that inhibition of GSK3-ß resulted in PTEN activation and subsequent decreased activation of AKT, leading to decreased p-P70S6kinase levels, indicating inhibition of the mTOR pathway. In addition, consistent with a negative role of GSK3-ß in ß-catenin stability through protein phosphorylation, we found that GSK3-ß inhibition resulted in an increase in ß-catenin levels. Simultaneous silencing of ß-catenin and inhibition of GSK3-ß demonstrated that ß-catenin is required for GSK3-ß-induced lymphangiogenesis.


Assuntos
Linfangiogênese/fisiologia , beta Catenina/metabolismo , Técnicas de Cultura de Células , Linhagem Celular , Células Endoteliais/fisiologia , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Glicogênio Sintase Quinase 3 beta/genética , Humanos , Indóis/farmacologia , Pulmão/citologia , Linfangiogênese/efeitos dos fármacos , Vasos Linfáticos/citologia , Maleimidas/farmacologia , Microvasos/citologia , Fosforilação , Estabilidade Proteica , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/metabolismo , beta Catenina/genética
17.
Mol Neurobiol ; 55(5): 3976-3989, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28551869

RESUMO

Studies have shown that the removal of the cholinergic innervation to the hippocampus induces dysfunction of the hypothalamic-pituitary-adrenocortical axis and decreases the number of glucocorticoid receptors (GRs). Subsequent studies have revealed that the loss of cholinergic input to the hippocampus reduces the expression of GRs and activates nuclear factor-kappa B (NF-κB) signaling through interactions with the cytoplasmic catalytic subunit of protein kinase A (PKAc). We examined the effects of chronic stress on cognitive status and GR-PKAc-NF-κB signaling in rats with a loss of cholinergic input to the hippocampus and cortex. Male Sprague-Dawley rats received 192 IgG-saporin injections to selectively eliminate cholinergic neurons in their basal forebrain. Two weeks later, rats were subjected to 1 h of restraint stress per day for 14 days. Rats subjected to both chronic stress and cholinergic depletion showed more severe memory impairments compared to those that received either treatment alone. The reduction in nuclear GR levels induced by cholinergic depletion was unaffected by chronic stress. The activation of NF-κB signaling in the hippocampus and the cerebral cortex induced by cholinergic depletion was augmented by chronic stress, resulting in the increased expression of pro-inflammatory markers, such as inducible nitric oxide synthase and cyclooxygenase-2. The activation of NF-κB induced by cholinergic depletion appears to be aggravated by chronic stress, and this might explain the increased susceptibility of patients with Alzheimer's disease to stress since activation of NF-κB is associated with stress.


Assuntos
Córtex Cerebral/metabolismo , Neurônios Colinérgicos/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Hipocampo/metabolismo , NF-kappa B/metabolismo , Receptores de Glucocorticoides/metabolismo , Aprendizagem Espacial , Estresse Psicológico/fisiopatologia , Animais , Peso Corporal , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Colina O-Acetiltransferase/metabolismo , Corticosterona/metabolismo , Ciclo-Oxigenase 2/metabolismo , Hipocampo/patologia , Hipocampo/fisiopatologia , Masculino , Memória , Óxido Nítrico Sintase Tipo II/metabolismo , Fosforilação , Fosfotreonina/metabolismo , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Transdução de Sinais , Estresse Psicológico/metabolismo , Estresse Psicológico/patologia
19.
Toxins (Basel) ; 9(5)2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28509866

RESUMO

Anthrax lethal toxin (LeTx) is a cytotoxic virulence factor that causes cell cycle arrest and cell death in various cell types. However, susceptibility to the cytotoxic effects varies depending on cell types. In proliferating monocytes, LeTx has only transient cytotoxic effects due to activation of the phosphoinositide 3-kinase (PI3K)-AKT-mediated adaptive responses. To date, the mechanism of LeTx in activating PI3K-AKT signaling axis is unknown. This study shows that the histone deacetylase 8 (HDAC8) is involved in activating PI3K-AKT signaling axis through down-regulating the phosphatase and tensin homolog 1 (PTEN) in human monocytic THP-1 cells. The HDAC8-specific activator TM-2-51 and inhibitor PCI-34051 enhanced and prevented, respectively, AKT activation and cell cycle progression in LeTx-treated cells. Furthermore, HDAC8 induced tri-methylation of histone H3 lysine 27 (H3K27me3), which is known to suppress PTEN expression, through at least in part down-regulating the H3K27me3 eraser Jumonji Domain Containing (JMJD) 3. Importantly, the JMJD3-specific inhibitor GSK-J4 induced AKT activation and protected cell cycle arrest in LeTx-treated cells, regardless the presence of HDAC8 activity. Collectively, this study for the first time demonstrated that HDAC8 activity determines susceptibility to cell cycle arrest induced by LeTx, through regulating the PI3K-PTEN-AKT signaling axis.


Assuntos
Antígenos de Bactérias/toxicidade , Toxinas Bacterianas/toxicidade , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Histona Desacetilases/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Repressoras/metabolismo , Sobrevivência Celular , Inativação Gênica , Histonas/metabolismo , Humanos , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Transdução de Sinais , Células THP-1
20.
Korean J Crit Care Med ; 32(3): 231-239, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31723641

RESUMO

BACKGROUND: Early recognition of the signs and symptoms of clinical deterioration could diminish the incidence of cardiopulmonary arrest. The present study investigates outcomes with respect to cardiopulmonary arrest rates in institutions with and without rapid response systems (RRSs) and the current level of cardiopulmonary arrest rate in tertiary hospitals. METHODS: This was a retrospective study based on data from 14 tertiary hospitals. Cardiopulmonary resuscitation (CPR) rate reports were obtained from each hospital to include the number of cardiopulmonary arrest events in adult patients in the general ward, the annual adult admission statistics, and the structure of the RRS if present. RESULTS: Hospitals with RRSs showed a statistically significant reduction of the CPR rate between 2013 and 2015 (odds ratio [OR], 0.731; 95% confidence interval [CI], 0.577 to 0.927; P = 0.009). Nevertheless, CPR rates of 2013 and 2015 did not change in hospitals without RRS (OR, 0.988; 95% CI, 0.868 to 1.124; P = 0.854). National university-affiliated hospitals showed less cardiopulmonary arrest rate than private university-affiliated in 2015 (1.92 vs. 2.40; OR, 0.800; 95% CI, 0.702 to 0.912; P = 0.001). High-volume hospitals showed lower cardiopulmonary arrest rates compared with medium-volume hospitals in 2013 (1.76 vs. 2.63; OR, 0.667; 95% CI, 0.577 to 0.772; P < 0.001) and in 2015 (1.55 vs. 3.20; OR, 0.485; 95% CI, 0.428 to 0.550; P < 0.001). CONCLUSIONS: RRSs may be a feasible option to reduce the CPR rate. The discrepancy in cardiopulmonary arrest rates suggests further research should include a nationwide survey to tease out factors involved in in-hospital cardiopulmonary arrest and differences in outcomes based on hospital characteristics.

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