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1.
Chemistry ; 25(60): 13748-13758, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31400031

RESUMO

Solid-state light-emitting electrochemical cells (LECs) have several advantages, such as low-voltage operation, compatibility with inert metal electrodes, large-area flexible substrates, and simple solution-processable device architectures. However, most of the studies on saturated red LECs show low or moderate device efficiencies (external quantum efficiency (EQE) <3.3 %). In this work, we demonstrate a series of five red-emitting cationic iridium complexes (RED1--RED5) with 2,2'-biquinoline ligands and test their electroluminescence (EL) characteristics in LECs. The Commission Internationale de l'Eclairage (CIE) 1931 coordinates for the LECs based on these complexes are all beyond the National Television System Committee (NTSC) red standard point (0.67, 0.33). The maximal EQE of the neat-film RED1-based LECs reaches 7.4 %. The reddest complex, RED3, is doped in the blue-emitting host complex, BG, to fabricate host-guest LECs. The maximal EQE of the host-guest LECs (1 wt % complex RED3) reaches 9.4 %, which is among the highest reported for the saturated red LECs.

2.
Heliyon ; 10(5): e26651, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38434312

RESUMO

Background: The correlation between acute ischemic stroke (AIS) and gut microbiota has opened a promising avenue for improving stroke prognosis through the utilization of specific gut bacterial species. This study aimed to identify gut bacterial species in AIS patients and their correlation with stroke severity, 3-month prognosis, and inflammatory markers. Methods: We enrolled 59 AIS patients (from June 2021 to July 2022) and 31 age-matched controls with similar cerebrovascular risk profiles but no stroke history. Fecal samples were analyzed using 16 S rDNA V3-V4 sequencing to assess α and ß diversity and identify significant microbiota differences. AIS cases were categorized based on the National Institute of Health Stroke Scale (NIHSS) scores and 3-month modified Rankin Scale (mRS) scores. Subgroup analyses were performed, and correlation analysis was used to examine associations between flora abundance, inflammatory markers and stroke outcome. Results: Significant differences in ß-diversity were observed between case and control groups (P < 0.01). Bacteroides dominated AIS samples, while Clostridia, Lachnospirales, Lachnospiraceae, Ruminococcaceae, Faecalibacterium, and Faecalibacterium prausnitzii were prominent in controls. Faecalibacterium and Faecalibacterium prausnitzii were significantly reduced in non-minor stroke and 3-month poor prognosis groups compared to controls, while this difference was less pronounced in patients with minor stroke and 3-month good prognosis. Both Faecalibacterium and Faecalibacterium prausnitzii were negatively correlated with the NIHSS score on admission (r = -0.48, -0.48, P < 0.01) and 3-month mRS score (r = -0.48, -0.44, P < 0.01). Additionally, they showed negative correlations with pro-inflammatory factors and positive correlations with anti-inflammatory factors (both P < 0.01). Conclusions: Faecalibacterium prausnitzii is negatively associated with stroke severity, impaired prognosis, and pro-inflammatory markers, highlighting its potential application in AIS treatments.

3.
J Alzheimers Dis ; 80(1): 321-330, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33523005

RESUMO

BACKGROUND: Increasing evidence supports an important role of vascular risk in cognitive decline and dementia. OBJECTIVE: This study aimed to examine whether vascular risk was associated with cognitive decline, cerebral hypometabolism, and clinical progression in cognitively intact elders. METHODS: Vascular risk was assessed by the Framingham Heart Study general Cardiovascular disease (FHS-CVD) risk score. The cross-sectional and longitudinal associations of FHS-CVD risk score with cognition and brain glucose metabolism were explored using multivariate linear regression and linear mixed effects models, respectively. The risk of clinical progression conversion was assessed using Kaplan-Meier survival curves and multivariate Cox proportional hazard models. RESULTS: A total of 491 cognitively intact elders were included from Alzheimer's Disease Neuroimaging Initiative (ADNI) database. Participants with high FHS-CVD risk scores had lower baseline Mini-Mental State Examination (MMSE) (p = 0.009), executive function (EF) (p < 0.001), memory function (MEM) (p < 0.001) scores, and F18-fluorodeoxyglucose positron emission tomography (FDG-PET) uptake (p < 0.001) than those with low FHS-CVD risk scores. In longitudinal analyses, individuals with higher FHS-CVD risk scores had greater longitudinal declines in MMSE (p = 0.043), EF (p = 0.029) scores, and FDG-PET uptake (p = 0.035). Besides, individuals with a higher vascular risk had an increased risk of clinical progression (p = 0.004). CONCLUSION: These findings indicated effects of vascular risk on cognitive decline, cerebral hypometabolism, and clinical progression. Early detection and management of vascular risk factors might be useful in the prevention of dementia.


Assuntos
Química Encefálica , Disfunção Cognitiva/complicações , Demência/complicações , Glucose/metabolismo , Doenças Vasculares/complicações , Idoso , Precursor de Proteína beta-Amiloide/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/psicologia , Estudos Transversais , Bases de Dados Factuais , Demência/diagnóstico por imagem , Demência/psicologia , Progressão da Doença , Função Executiva , Feminino , Humanos , Estimativa de Kaplan-Meier , Estudos Longitudinais , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Neuroimagem , Tomografia por Emissão de Pósitrons , Fatores de Risco , Doenças Vasculares/diagnóstico por imagem
4.
Anesthesiology ; 108(5): 873-81, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18431123

RESUMO

BACKGROUND: : Resuscitation with hypertonic saline or hypertonic saline plus l-arginine acutely improves cerebral blood flow after traumatic brain injury (TBI) followed by hemorrhagic hypotension. The authors investigated whether hypertonic saline or hypertonic l-arginine would improve long-term neuronal survival and behavioral outcomes 15 days after TBI and hemorrhagic hypotension. METHODS: : Mean arterial pressure, arterial blood gases, pH, plasma glucose, hematocrit, and hemoglobin were measured in male Sprague-Dawley rats before and after moderate (2.0 atm) fluid percussion TBI. Rats were assigned to one of six groups: (1) sham TBI, (2) hemorrhage only, (3) TBI only, (4) TBI plus hemorrhage and resuscitation with 0.9% saline, (5) TBI plus hemorrhage and resuscitation with hypertonic saline (7.5%), or (6) TBI plus hemorrhage and resuscitation with l-arginine (100 mg/kg) in hypertonic saline. On postinjury days 1-5, vestibulomotor function was assessed using beam balance and beam walking tasks. On postinjury days 11-15, spatial memory function was assessed using the Morris water maze. After behavioral testing, neuronal counting was performed bilaterally on specific hippocampal regions. RESULTS: : Groups receiving hypertonic saline (P < 0.05, day 15 vs. day 11) or hypertonic l-arginine (P < 0.05, days 13-15 vs. day 11) showed improved performance over time on the Morris water maze, as well as significantly improved neuronal survival in the contralateral hippocampus (P < 0.05, hypertonic saline or hypertonic l-arginine vs. normal saline) compared with untreated TBI or normal saline-treated TBI plus hemorrhage groups. CONCLUSIONS: : Hypertonic saline and hypertonic l-arginine were both effective at promoting long-term neuronal survival and behavioral recovery. The slightly earlier improvement in Morris water maze performance in the hypertonic l-arginine group warrants further studies to determine whether higher doses of l-arginine provide additional improvement. This study supports the therapeutic benefits of hypertonic resuscitation after TBI plus hemorrhagic hypotension.


Assuntos
Lesões Encefálicas/complicações , Lesões Encefálicas/tratamento farmacológico , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/etiologia , Soluções Hipertônicas/uso terapêutico , Ressuscitação/métodos , Solução Salina Hipertônica/uso terapêutico , Animais , Arginina/uso terapêutico , Comportamento/efeitos dos fármacos , Comportamento/fisiologia , Lesões Encefálicas/psicologia , Hemorragia Cerebral/psicologia , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
5.
Clin Rheumatol ; 35(10): 2557-64, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26898984

RESUMO

This study aimed to determine the most suitable site for diagnosis of carpal tunnel syndrome (CTS) by examining an 8-site measurement of the median nerve's cross-sectional area (CSA). A total of 36 wrists of 26 patients with nerve conduction study (NCS) proven CTS, along with 34 wrists of 23 controls whose age and gender were matched with the patients, were evaluated with ultrasonography. The CSAs of the median nerve at eight predetermined sites including at the sites of 3, 2, and 1 cm proximal to the wrist crease, wrist crease, as well as at the sites of 1, 2, 3. and 4 cm distal to the wrist crease were obtained. The correlation between CSA and NCS severity, and duration of clinical CTS symptoms was analyzed. Receiver operating characteristic (ROC) curves was applied to determine the optimum cut-off point and to evaluate the diagnostic sensitivity and specificity of sonographic measurements. The CSAs of the median nerves at the eight sites were significantly higher in the CTS subjects, relative to the controls. Moreover, anatomical variation of the median nerve was found in the CTS group. ROC results indicated the areas under curve (AUC) at the site of 4 cm distal to the wrist crease were the largest with 0.874 cm(2), and an optimal cut-off value of 0.095 yielded a sensitivity of 88.9 % and a specificity of 76.5 %. The CSAs of "CTS-wrists" positively correlated with NCS severities and the CTS symptoms duration. Using 8-site CSAs measurement of the median nerve from inlet to outlet has positive correlations with NCS severity and duration of CTS symptoms.


Assuntos
Síndrome do Túnel Carpal/diagnóstico por imagem , Nervo Mediano/diagnóstico por imagem , Ultrassonografia/métodos , Idoso , Síndrome do Túnel Carpal/fisiopatologia , Eletrodiagnóstico , Feminino , Humanos , Masculino , Nervo Mediano/fisiopatologia , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Sensibilidade e Especificidade
6.
J Neurotrauma ; 31(8): 739-48, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24341563

RESUMO

Gap junctions (GJs) contribute to cerebral vasodilation, vasoconstriction, and, perhaps, to vascular compensatory mechanisms, such as autoregulation. To explore the effects of traumatic brain injury (TBI) on vascular GJ communication, we assessed GJ coupling in A7r5 vascular smooth muscle (VSM) cells subjected to rapid stretch injury (RSI) in vitro and VSM in middle cerebral arteries (MCAs) harvested from rats subjected to fluid percussion TBI in vivo. Intercellular communication was evaluated by measuring fluorescence recovery after photobleaching (FRAP). In VSM cells in vitro, FRAP increased significantly (p<0.05 vs. sham RSI) after mild RSI, but decreased significantly (p<0.05 vs. sham RSI) after moderate or severe RSI. FRAP decreased significantly (p<0.05 vs. sham RSI) 30 min and 2 h, but increased significantly (p<0.05 vs. sham RSI) 24 h after RSI. In MCAs harvested from rats 30 min after moderate TBI in vivo, FRAP was reduced significantly (p<0.05), compared to MCAs from rats after sham TBI. In VSM cells in vitro, pretreatment with the peroxynitrite (ONOO(-)) scavenger, 5,10,15,20-tetrakis(4-sulfonatophenyl)prophyrinato iron[III], prevented RSI-induced reductions in FRAP. In isolated MCAs from rats treated with the ONOO(-) scavenger, penicillamine, GJ coupling was not impaired by fluid percussion TBI. In addition, penicillamine treatment improved vasodilatory responses to reduced intravascular pressure in MCAs harvested from rats subjected to moderate fluid percussion TBI. These results indicate that TBI reduced GJ coupling in VSM cells in vitro and in vivo through mechanisms related to generation of the potent oxidant, ONOO(-).


Assuntos
Lesões Encefálicas/fisiopatologia , Encéfalo/fisiopatologia , Comunicação Celular/fisiologia , Junções Comunicantes/patologia , Músculo Liso Vascular/fisiopatologia , Animais , Encéfalo/irrigação sanguínea , Circulação Cerebrovascular/fisiologia , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley
7.
Surgery ; 150(5): 887-96, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21676422

RESUMO

BACKGROUND: Intracranial hypertension complicates severe traumatic brain injury frequently and might be associated with poor outcomes. Traumatic brain injury induces a neuroinflammatory response by microglial activation and upregulation of proinflammatory cytokines, such as interleukin-1ß, tumor necrosis factor alpha, and interleukin-6. To elucidate the effect of increased intracranial pressure on microglial function, we studied the effects of increased extracellular pressure on primary human microglial cell phagocytosis, proliferation, cytokine secretion, and total nitrate production. In addition, because many patients receive propofol during anesthesia or intensive care unit sedation, we evaluated whether propofol alters the effects of pressure. METHODS: Human microglial cells were pretreated with (2.5-20 µg/mL) propofol or Intralipid as a vehicle control were incubated at ambient atmospheric pressure or at 15 or 30 mm Hg increased pressure for 2 h for phagocytosis assays or 24 h for proliferation, cytokine secretion, and total nitrate production studies. Phagocytosis was determined by incorporation of intracellular fluorescent latex beads. Tumor necrosis factor alpha, interleukin-1ß, and interleukin-6 were assayed by sandwich enzyme-linked immunosorbent assay and total nitrate by Greiss reagent. RESULTS: Increased extracellular pressure stimulated phagocytosis versus untreated microglial cells or cells treated with an Intralipid vehicle control. Propofol also stimulated microglial phagocytosis at ambient pressure. Increased pressure, however, decreased phagocytosis in the presence of propofol. Pressure also increased microglial tumor necrosis factor-α and interleukin-1ß secretion and propofol pretreatment blocked the pressure-stimulated effect. Interleukin-6 production was not altered either by pressure or by propofol. Pressure also induced total nitrate secretion, and propofol pretreatment decreased basal as well as pressure-induced microglial nitrate production. CONCLUSION: Extracellular pressures consistent with increased intracranial pressure after a head injury activate inflammatory signals in human primary microglial cells in vitro, stimulating phagocytosis, proliferation, tumor necrosis factor-α, interleukin-1ß, and total nitrate secretion but not affecting interleukin-6. Such inflammatory events may contribute to the worsened prognosis of traumatic brain injury after increased intracranial pressure. Because propofol alleviated these potentially proinflammatory effects, these results suggest that the inflammatory cascade activated by intracranial pressure might be targeted by propofol in patients with increased intracranial pressure after traumatic brain injury.


Assuntos
Citocinas/metabolismo , Hipertensão Intracraniana/tratamento farmacológico , Microglia/efeitos dos fármacos , Nitratos/metabolismo , Fagocitose/efeitos dos fármacos , Propofol/farmacologia , Anestésicos Intravenosos/farmacologia , Bioensaio/métodos , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Humanos , Concentração de Íons de Hidrogênio , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Hipertensão Intracraniana/metabolismo , Hipertensão Intracraniana/patologia , Microglia/citologia , Microglia/metabolismo , Oxigênio/farmacologia , Pressão , Fator de Necrose Tumoral alfa/metabolismo
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