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1.
Inorg Chem ; 62(27): 10762-10771, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37377386

RESUMO

The successful management and safe disposal of high-level nuclear waste necessitate the efficient separation of actinides (An) from lanthanides (Ln), which has emerged as a crucial prerequisite. Mixed donor ligands incorporating both soft and hard donor atoms have garnered interest in the field of An/Ln separation and purification. One such example is nitrilotriacetamide (NTAamide) derivatives, which have demonstrated selectivity in extracting minor actinide Am(III) ions over Eu(III) ions. Nevertheless, the Am/Eu complexation behavior and selectivity remain underexplored. In the work, a comprehensive and systematic investigation has been conducted for [M(RL)(NO3)3] complexes (M = Am and Eu) utilizing relativistic density functional theory. The NTAamide ligand (RL) is substituted with various alkyl groups, namely, methyl, ethyl, propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, and n-octyl. Thermodynamic calculations show that the alkyl chain length in NTAamide is capable of tuning the separation selectivity of Am and Eu. Moreover, the differences in calculated free energies between Am and Eu complexes are more negative for R = Bu-Oct than Me-Pr. This indicates that elongation of the alkyl chain can increase the efficiency of selective separation of Am(III) from Eu(III). Based on the quantum theory of atoms in molecules and charge decomposition analyses, it has been observed that the strength of Am-RL bonds is higher than that of Eu-RL bonds. This disparity is attributed to a greater degree of covalency in Am-RL bonds and a higher level of charge transfer from ligands to Am within complexes containing these bonds. Energies of occupied orbitals with the central N character are recognized overall lower for [Am(OctL)(NO3)3] than for [Eu(OctL)(NO3)3], indicative of stronger complexation stability of the former. These results offer valuable insights into the separation mechanism of NTAamide ligands, which can help guide the development of more powerful agents for An/Ln separation in future applications.

2.
J Am Chem Soc ; 144(8): 3449-3457, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-35057612

RESUMO

Developing materials that possess colorimetric responses to external stimuli is a promising strategy for addressing the current challenges in radiation dosimetry. Currently, colorimetric ionizing-radiation-responsive materials remain underexplored, and those with multistimuli response are rare. Herein, the integration of thorium cation and photoresponsive terpyridine carboxylate ligand gives rise to a thorium nanocluster, Th-101, which displays the second case of fluorochromic response and unprecedented piezochromic behavior among all actinide materials. The emission color of Th-101 exhibits a gradual transition from blue to cyan to green upon irradiation with accumulated dose, which renders colorimetric dosimetry of ionizing radiation based on a red-green-blue (RGB) concept. Further fabricating Th-101 into a custom-built optoelectronic device allows for on-site quantification of radiation dose with merits of ease of operation, rapid readout, and cost-effectiveness.


Assuntos
Corantes Fluorescentes , Tório , Colorimetria
3.
Molecules ; 27(18)2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36144824

RESUMO

Transition metal oxides (TMOs) and actinide ones (AnOs) have been widely applied in catalytic reactions due to their excellent physicochemical properties. However, the reaction pathway and mechanism, especially involving TM-An heterometallic centers, remain underexplored. In this respect, relativistic density functional theory (DFT) was used to examine uranium-doped zinc, copper, and nickel oxides for their catalytic activity toward the conversion of furfural to furfuryl alcohol. A comparison was made with their undoped TMOs. It was found that the three TMOs were capable of catalyzing the reaction, where the free energies of adsorption, hydrogenation, and desorption fell between -33.93 and 45.00 kJ/mol. The uranium doping extremely strengthened the adsorption of CuO-U and NiO-U toward furfural, making hydrogenation or desorption much harder. Intriguingly, ZnO-U showed the best catalytic performance among all six catalyst candidates, as its three reaction energies were very small (-10.54-8.12 kJ/mol). The reaction process and mechanism were further addressed in terms of the geometrical, bonding, charge, and electronic properties.

4.
Int J Qual Health Care ; 27(5): 361-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26239475

RESUMO

OBJECTIVE: This study explores the association between coronary artery bypass surgery (CABG) patients' residence and quality of care in terms of 30-day mortality. DESIGN: A retrospective, multilevel study design was conducted using claims data from Taiwan's Universal Health Insurance Scheme. Hospital and surgeon's CABG operation volume, risk-adjusted surgical site infection rate and risk-adjusted 30-day mortality rate in the previous year were adopted as performance indicators, and the level of quality was evaluated via K-means clustering algorithm. Baron and Kenny's procedures for mediation effect were conducted. SETTING: Hospitals in Taiwan. PARTICIPANTS: Patients who underwent CABG surgeries from 1 January 2008 to 30 September 2011 were identified in this study. However, patients who were under the age of 18 years or above the age of 85(n = 164), with missing data for gender (n = 3) or received surgeries from surgeons who never performed any CABG surgeries (n = 27), were excluded. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Thirty-day mortality. RESULTS: There were 9973 CABG surgeries included in this study. Patients who lived in urban areas received better quality of care (28.90 vs. 21.57%) and enjoyed better outcome (4.33 vs. 6.84%). After the procedure of mediation effect testing, the results showed that the relationship between patient residence's urbanization level and 30-day mortality was partially mediated by patterns of quality of care. CONCLUSIONS: The rural-dwelling CABG patients are less likely to approach the better performing healthcare providers, and this tendency indirectly affects their treatment outcomes. Policymakers still need to develop strategies to ensure better equity in access to quality health care.


Assuntos
Ponte de Artéria Coronária/mortalidade , Ponte de Artéria Coronária/estatística & dados numéricos , Qualidade da Assistência à Saúde/estatística & dados numéricos , Características de Residência/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Estudos Transversais , Feminino , Humanos , Revisão da Utilização de Seguros , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Indicadores de Qualidade em Assistência à Saúde , Estudos Retrospectivos , Fatores Sexuais , Taiwan , Adulto Jovem
5.
Int J Equity Health ; 13: 64, 2014 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-25052723

RESUMO

BACKGROUND: Equity is an important issue in the healthcare research field. Many studies have focused on the relationship between patient characteristics and outcomes of care. These studies, however, have seldom examined whether patients' characteristics affected their access to quality healthcare, which further affected the care outcome. The purposes of this study were to determine whether low-income coronary artery bypass surgery (CABG) patients receive healthcare services with poorer quality, and if such differences in treatment result in different outcomes. METHODS: A retrospective multilevel study design was conducted using claims data from Taiwan's universal health insurance scheme for 2005-2008. Patients who underwent their CABG surgery between 2006 and 2008 were included in this study. CABG patients who were under 18 years of age or had unknown gender or insured classifications were excluded. Hospital and surgeon's performance indicators in the previous one year were used to evaluate the level of quality via k-means clustering algorithm. Baron and Kenny's procedures for mediation effect were conducted to explore the relationship among patient's income, quality of CABG care, and inpatient mortality. RESULTS: A total of 10,320 patients were included in the study. The results showed that 5.65% of the low-income patients received excellent quality of care, which was lower than that of patients not in the low-income group (5.65% vs.11.48%). The mortality rate of low-income patients (12.10%) was also higher than patients not in the low-income group (5.25%). Also, the mortality of patients who received excellent care was half as low as patients receiving non-excellent care (2.63% vs. 5.68%). Finally, after the procedure of mediation effect testing, the results showed that the relationship between patient income level and CABG mortality was partially mediated by patterns of quality of care. CONCLUSIONS: The results of the current study implied that worse outcome in low-income CABG patients might be associated with poorer quality of received services. Health authorities should pay attention to this issue, and propose appropriate solutions.


Assuntos
Ponte de Artéria Coronária/normas , Acessibilidade aos Serviços de Saúde/normas , Disparidades em Assistência à Saúde/estatística & dados numéricos , Renda/estatística & dados numéricos , Qualidade da Assistência à Saúde/estatística & dados numéricos , Adulto , Idoso , Análise de Variância , Estudos Transversais , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taiwan/epidemiologia
6.
BMC Med Inform Decis Mak ; 14: 42, 2014 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-24884488

RESUMO

BACKGROUND: Claims data has usually been used in recent studies to identify cases of healthcare-associated infection. However, several studies have indicated that the ICD-9-CM codes might be inappropriate for identifying such cases from claims data; therefore, several researchers developed alternative identification models to correctly identify more cases from claims data. The purpose of this study was to investigate three common approaches to develop alternative models for the identification of cases of coronary artery bypass graft (CABG) surgical site infection, and to compare the performance between these models and the ICD-9-CM model. METHODS: The 2005-2008 National Health Insurance claims data and healthcare-associated infection surveillance data from two medical centers were used in this study for model development and model verification. In addition to the use of ICD-9-CM codes, this study also used classification algorithms, a multivariable regression model, and a decision tree model in the development of alternative identification models. In the classification algorithms, we defined three levels (strict, moderate, and loose) of the criteria in terms of their strictness. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were used to evaluate the performance of each model. RESULTS: The ICD-9-CM-based model showed good specificity and negative predictive value, but sensitivity and positive predictive value were poor. Performances of the other models were varied, except for negative predictive value. Among the models, the performance of the decision tree model was excellent, especially in terms of positive predictive value. CONCLUSION: The accuracy of identification of cases of CABG surgical site infection is an important issue in claims data. Use of the decision tree model to identify such cases can improve the accuracy of patient-level outcome research. This model should be considered when performing future research using claims data.


Assuntos
Ponte de Artéria Coronária , Monitoramento Epidemiológico , Formulário de Reclamação de Seguro , Programas Nacionais de Saúde , Infecção da Ferida Cirúrgica/epidemiologia , Idoso , Antibacterianos/uso terapêutico , Ponte de Artéria Coronária/efeitos adversos , Feminino , Indicadores Básicos de Saúde , Humanos , Classificação Internacional de Doenças , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Estudos Retrospectivos , Sensibilidade e Especificidade , Infecção da Ferida Cirúrgica/tratamento farmacológico , Infecção da Ferida Cirúrgica/etiologia , Taiwan
7.
Chemosphere ; 324: 138325, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36889472

RESUMO

It is desirable but challenging to sense toxic nitrogen dioxide (NO2) for it has become one of the most prominent air pollutants. Zinc oxide-based gas sensors are known to detect NO2 gas efficiently, however, the sensing mechanism and involved intermediates structures remain underexplored. In the work, a series of sensitive materials, including zinc oxide (ZnO) and its composites ZnO/X [X = Cel (cellulose), CN (g-C3N4) and Gr (graphene)] have been comprehensively examined by density functional theory. It is found that ZnO favors adsorbing NO2 over ambient O2, and produces nitrate intermediates; and H2O is chemically held by zinc oxide, in line with the non-negligible impact of humidity on the sensitivity. Of the formed composites, ZnO/Gr exhibits the best NO2 gas-sensing performance, which is proved by the calculated thermodynamics and geometrical/electronic structures of reactants, intermediates and products. The interfacial interaction has been elaborated on for composites (ZnO/X) as well as their complexes (ZnO- and ZnO/X-adsorbates). The current study well explains experimental findings and opens up a way to design and unearth novel NO2 sensing materials.


Assuntos
Poluentes Atmosféricos , Grafite , Óxido de Zinco , Óxido de Zinco/química , Grafite/química , Dióxido de Nitrogênio/análise , Poluentes Atmosféricos/análise , Celulose
8.
J Integr Med ; 20(6): 575-580, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36123283

RESUMO

This report presents the case of a 59-year-old man with severe COVID-19 that gradually progressed to cytokine release syndrome and then acute respiratory distress syndrome; he was successfully treated via integration of therapeutic plasma exchange and traditional Chinese medicine. The patient initially presented with a sore throat, severe muscle aches, productive cough and fever. On the worsening of symptoms, remdesivir was administered. However, as the symptoms continued to worsen and a cytokine release syndrome was suspected, oxygen was provided through a high-flow nasal cannula (50 L/min) and therapeutic plasma exchange was performed to prevent worsening of the acute respiratory distress syndrome. On the same day, a course of traditional Chinese medicine was introduced in consultation with the infectious house staff. The patient's symptoms gradually improved; the levels of C-reactive protein and D-dimers reduced, and the patient was weaned to a simple oxygen mask and eventually to room air. This is the first reported case of the integration of these treatments. Together, they prevented the patient from requiring intubation, played a role in cytokine management, and also improved the clinical symptoms, including productive purulent sputum, cough, frequent stool passage and intermittent fever, with no adverse effects. As a result, the patient was discharged within two weeks of the integration of these treatments. Therefore, the integration of therapeutic plasma exchange and traditional Chinese medicine is an effective therapy for patients with severe COVID-19.


Assuntos
COVID-19 , Síndrome do Desconforto Respiratório , Masculino , Humanos , Pessoa de Meia-Idade , COVID-19/terapia , Síndrome da Liberação de Citocina , Troca Plasmática , Medicina Tradicional Chinesa , Tosse/tratamento farmacológico , Síndrome do Desconforto Respiratório/terapia , Oxigênio/uso terapêutico
9.
Toxicol Appl Pharmacol ; 257(1): 137-47, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21925195

RESUMO

This study aimed to explore the mechanisms by which prodigiosin protects against hypoxia-induced oxidative/nitrosative brain injury induced by middle cerebral artery occlusion/reperfusion (MCAo/r) injury in mice. Hypoxia in vitro was modeled using oxygen-glucose deprivation (OGD) followed by reoxygenation of BV-2 microglial cells. Our results showed that treatment of mice that have undergone MCAo/r injury with prodigiosin (10 and 100µg/kg, i.v.) at 1h after hypoxia ameliorated MCAo/r-induced oxidative/nitrosative stress, brain infarction, and neurological deficits in the mice, and enhanced their survival rate. MCAo/r induced a remarkable production in the mouse brains of reactive oxygen species (ROS) and a significant increase in protein nitrosylation; this primarily resulted from enhanced expression of NADPH oxidase 2 (gp91(phox)), inducible nitric oxide synthase (iNOS), and the infiltration of CD11b leukocytes due to breakdown of blood-brain barrier (BBB) by activation of nuclear factor-kappa B (NF-κB). All these changes were significantly diminished by prodigiosin. In BV-2 cells, OGD induced ROS and nitric oxide production by up-regulating gp91(phox) and iNOS via activation of the NF-κB pathway, and these changes were suppressed by prodigiosin. In conclusion, our results indicate that prodigiosin reduces gp91(phox) and iNOS expression possibly by impairing NF-κB activation. This compromises the activation of microglial and/or inflammatory cells, which then, in turn, mediates prodigiosin's protective effect in the MCAo/r mice.


Assuntos
Hipóxia-Isquemia Encefálica/prevenção & controle , Glicoproteínas de Membrana/antagonistas & inibidores , NADPH Oxidases/antagonistas & inibidores , Fármacos Neuroprotetores/uso terapêutico , Óxido Nítrico Sintase Tipo II/biossíntese , Prodigiosina/uso terapêutico , Animais , Western Blotting , Relação Dose-Resposta a Droga , Masculino , Glicoproteínas de Membrana/biossíntese , Camundongos , Camundongos Endogâmicos ICR , NADPH Oxidase 2 , NADPH Oxidases/biossíntese , Fármacos Neuroprotetores/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Nitrosação/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Prodigiosina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Tirosina/análogos & derivados , Tirosina/biossíntese
10.
Int J Biol Macromol ; 191: 584-590, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34582905

RESUMO

The specification of the local structure and clarification of interfacial interactions of biomass composites is of tremendous significance in synthesizing novel materials and advancing their performance in various demanding applications. However, it remains challenging due to the limitations of experimental techniques, particularly for the manner that biomass composites commonly have hydrogen bonds involved in the vicinity of active sites and interfaces. Herein, the cellulose/Mg(OH)2 nanocomposite has been synthesized via a simple hydrothermal approach and examined by density functional theory (DFT) calculations. The composite exhibits a layered morphology; Mg(OH)2 flakes are around 50 nm in size and well-dispersed. They either anchor onto the cellulose surface or intercalate between layers. The specific composite structure was confirmed theoretically, in line with XRD, SEM and TEM observations. The interfacial interactions were found to be hydrogen bonding. The average adsorption energy per hydroxyl group was computed to be within -0.47 and -0.26 eV for a composite model comprising three cellulose chains and a two-layered Mg(OH)2 cluster. The combined computational/experimental results allow to postulate the antibacterial mechanism of the nanocomposite.


Assuntos
Antibacterianos/química , Celulose/análogos & derivados , Hidróxido de Magnésio/química , Nanocompostos/química , Adsorção , Antibacterianos/farmacologia , Biomassa , Ligação de Hidrogênio , Termodinâmica
11.
J Tradit Complement Med ; 10(5): 504-510, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32953567

RESUMO

BACKGROUND: Traumatic brain injury (TBI) is characterized by high prevalence, morbidity, and mortality. Diffuse axonal injury (DAI) is a specific type of TBI leading to prolonged consciousness impairment and disability. There is still no standard treatment for DAI, so we introduced traditional Chinese medicine into the treatment of these patients. CASE SUMMARIES: Three patients had TBI after traffic accidents. Their Glasgow Coma Scale (GCS) scores in the intensive care unit (ICU) were E1VEM2-3, E1VEM2-3, and E1VEM2 respectively. All of them were diagnosed with DAI based on magnetic resonance imaging (MRI). Because of continuing consciousness disturbances, their families agreed to combine traditional Chinese medicine and modern medicine treatments through inpatient consultation in Taoyuan General hospital. Two patients took Buyang Huanwu Decoction, and one Tianma Gouteng Decoction twice a day. All of them received 20 min of acupuncture treatments 5 times per week. Acupuncture points included Baihui (GV20), Sishencong (EX-HN1), Shuigou (GV26), Hegu (LI4), and Taichong (LR3). All of them started Traditional Chinese medicine treatment within 2 weeks after TBI. The GCS of all three patients recovered to E4M5V6. CONCLUSIONS: The early addition of traditional Chinese medicine treatments to Western medical care can improve the prognosis of patients with diffuse axonal injury.

12.
Medicine (Baltimore) ; 98(51): e18195, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31860966

RESUMO

The finding of a decrease in subsequent fibroid-related operation following the use of Chinese herbal products (CHPs) has led to speculation that CHPs might play a role in uterine fibroids prevention.This study provides an overview of uterine fibroids incidence, comparing CHP users with those who do not use CHPs, referred to as non-CHP users. The results can provide information to clinicians for counseling women about the preventive use of CHPs.A total of 52,151 women (20-45 years of age) were recruited from a nationwide 1-million-person representative sample of those covered by National Health Insurance in Taiwan and were followed from 2000 to 2013. Exact matching was performed for comparative analysis. The age-specific hazard ratios (HRs) of uterine fibroids in relation to either CHP or the phytoestrogen use were calculated with multivariate Cox proportional hazard regression.More than 71% of patients had used a CHP at some point previously. The overall incidence density rate of uterine fibroids for non-CHP users was estimated at 27.5 per 1000 patient-years. The corresponding values for CHP and the phytoestrogen users were lower than those of the non-CHP group (CHP group = 15.5; the phytoestrogen group = 12.5 per 1000 patient-years). The covariate adjusted HRs for uterine fibroid were 0.73 (95% confidence interval [CI] 0.63-0.85) and 0.65 (95% CI 0.52-0.82) in women using CHPs and the phytoestrogen, respectively.CHPs seem to contribute to a decreased risk in developing uterine fibroids. Although the mechanism of action of these products is unclear, their use as a preventive agent for uterine fibroids might be taken into consideration.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Leiomioma/prevenção & controle , Adulto , Fatores Etários , Estudos de Coortes , Humanos , Leiomioma/epidemiologia , Pessoa de Meia-Idade , Fatores de Risco , Taiwan/epidemiologia , Adulto Jovem
13.
Eur J Pharmacol ; 555(2-3): 211-7, 2007 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-17109845

RESUMO

Evodia rutaecarpa is commonly used as an anti-inflammatory drug in traditional Chinese medicine. We previously identified four bioactive compounds (dehydroevodiamine (I), evodiamine (II), rutaecarpine (III), and synephrine (IV)) from the ethanol extract of E. rutaecarpa, but their effects and mechanism(s) of action remain unclear. To study the anti-inflammatory potential and the possible underlying mechanism(s), their effects on phorbol-12-myristate-13-acetate (PMA)- and N-formyl-methionyl-leucyl-phenylalanine (fMLP)-induced reactive oxygen species production in neutrophils was studied, as well as lipopolysaccharide (LPS)-induced nitric oxide (NO) production and inducible NO synthetase (iNOS) expression in microglial cells. The ethanol extract of E. rutaecarpa displayed potent antioxidative effects against both PMA- and fMLP-induced reactive oxygen species production in neutrophils (with IC50 values of around 2.7-3.3 microg/ml). Although less potent than the ethanol extract of E. rutaecarpa, compounds I-IV all concentration-dependently inhibited PMA- and fMLP-induced reactive oxygen species production, with compound IV consistently being the most potent agent among these active components. The antioxidative effects of the ethanol extract of E. rutaecarpa and these compounds were partially due to inhibition (10%-33%) of NADPH oxidase activity, a predominant reactive oxygen species-producing enzyme in neutrophils, and to a minor extent to their direct radical-scavenging properties. The ethanol extract of E. rutaecarpa also inhibited LPS-induced NO production (with an IC50 of around 0.8 microg/ml) and iNOS upregulation in microglial cells that was partially mimicked by compounds I, II, and III, but not compound IV. Our results suggest that the ethanol extract of E. rutaecarpa and its four bioactive components all exhibited anti-inflammatory activities which could be partially explained by their different potentials for inhibiting NADPH oxidase-dependent reactive oxygen species and/or iNOS-dependent NO production in activated inflammatory cells.


Assuntos
Alcaloides/farmacologia , Anti-Inflamatórios/farmacologia , Evodia/química , Alcaloides Indólicos/farmacologia , Extratos Vegetais/farmacologia , Quinazolinas/farmacologia , Sinefrina/farmacologia , Animais , Compostos de Bifenilo/farmacologia , Linhagem Celular , Etanol/química , Humanos , Hidrazinas/farmacologia , Camundongos , Microglia/citologia , Microglia/metabolismo , N-Formilmetionina Leucil-Fenilalanina/farmacologia , NADPH Oxidases/metabolismo , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/metabolismo , Picratos , Espécies Reativas de Oxigênio/metabolismo , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/farmacologia
14.
J Pharm Pharmacol ; 58(1): 129-35, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16393473

RESUMO

Rapid production of reactive oxygen species (ROS) and upregulation of beta2 integrin by leucocytes are two important inflammatory responses in human leucocytes. To evaluate whether three phenylpropanoid glycosides (acteoside, crenatoside, and rossicaside B) and two iridoid glucosides (boschnaloside and 8-epideoxyloganic acid) identified from two medicinal plants with similar indications (Orobanche caerulescens and Boschniakia rossica) exhibited anti-inflammatory activity, their effects on N-formyl-methionyl-leucyl-phenylalanine (fMLP) and phorbol-12-myristate-13-acetate (PMA)-activated peripheral human neutrophils (PMNs) and mononuclear cells were examined. Pretreatment with 1-50 microM phenylpropanoid glycoside concentration-dependently diminished PMA- and fMLP-induced ROS production with IC50 values of approximately 6.8-23.9 and 3.0-8.8 muM, respectively. Iridoid glucoside was less effective than phenylpropanoid glycoside with an IC50 value of approximately 8.9-28.4 microM in PMA-activated PMNs and 19.1-21.1 microM in fMLP-activated mononuclear cells. Phenylpropanoid glycosides also effectively inhibited NADPH oxidase (NOX) and displayed potent free radical-scavenging activity, but did not interfere with pan-protein kinase C (PKC) activity. Furthermore, all compounds, except rossicaside B, significantly inhibited PMA- and fMLP-induced Mac-1 (a beta2 integrin) upregulation at 50 microM but not that of fMLP-induced intracellular calcium mobilization. These drugs had no significant cytotoxicity as compared with the vehicle control. Our data suggested that inhibition of ROS production, possibly through modulation of NOX activity and/or the radical scavenging effect, and beta2 integrin expression in leucocytes indicated that these compounds had the potential to serve as anti-inflammatory agents during oxidative stress.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Ácidos Cafeicos/farmacologia , Glucosídeos/farmacologia , Iridoides/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Fenóis/farmacologia , Compostos de Bifenilo/metabolismo , Antígenos CD18/metabolismo , Células Cultivadas , Radicais Livres/metabolismo , Humanos , Hidrazinas/metabolismo , Leucócitos Mononucleares/metabolismo , Antígeno de Macrófago 1/imunologia , N-Formilmetionina Leucil-Fenilalanina , NADPH Oxidases/metabolismo , Neutrófilos/metabolismo , Picratos , Proteína Quinase C/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Acetato de Tetradecanoilforbol/análogos & derivados
15.
PLoS One ; 11(4): e0152776, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27054711

RESUMO

BACKGROUND: Equal access to healthcare facilities and high-level quality of care are important strategies to eliminate the disparity in outcome of care. However, the existing literature regarding how urban or rural dwelling patients with different income level select healthcare providers is insufficient. The purposes of this study were to examine whether differences of healthcare provider selection exist among urban and rural coronary artery bypass surgery (CABG) patients with different income level. If so, we further investigated the associated impact on mortality. METHODS: A retrospective, multilevel study design was conducted using claims data from 2007-2011 Taiwan's Universal Health Insurance Scheme. Healthcare providers' performance and patients' travelling distance to hospitals were used to define the patterns of healthcare provider selection. Baron and Kenny's procedures for mediation effect were conducted. RESULTS: There were 10,108 CABG surgeries included in this study. The results showed that urban dwelling and higher income patients were prone to receive care from better-performance providers. The travelling distances of urban dwelling patients was 15 KM shorter, especially when they received better-performance provider's care. The results also showed that the difference of healthcare provider selection and mortality rate existed between rural and urban dwelling patients with different income levels. After the procedure of mediation effect testing, the results showed that the healthcare provider selection partially mediated the relationships between patients' residential areas with different income levels and 30-day mortality. CONCLUSION: Preferences of healthcare provider selection vary among rural and urban patients with different income, and such differences partially mediated the outcome of care. Health authorities should pay attention to this issue, and propose appropriate solutions to eliminate the disparity in outcome of CABG care.


Assuntos
Ponte de Artéria Coronária/mortalidade , Pessoal de Saúde , Renda , População Rural , População Urbana , Estudos Transversais , Acessibilidade aos Serviços de Saúde , Disparidades em Assistência à Saúde , Hospitais , Humanos , Preferência do Paciente , Estudos Retrospectivos , População Rural/estatística & dados numéricos , Taiwan/epidemiologia , População Urbana/estatística & dados numéricos
16.
Free Radic Biol Med ; 99: 508-519, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27609227

RESUMO

Salvianolic acid A (SalA), a chemical type of caffeic acid trimer, has drawn great attention for its potent bioactivities against ischemia-induced injury both in vitro and in vivo. In this study, we evaluated SalA's protective effects against acute ischemic stroke by inducing middle cerebral artery occlusion/reperfusion (MCAO) injuries in mice. Treatment of the mice with SalA (50 and 100µg/kg, i.v.) at 2h after MCAO enhanced their survival rate, improved their moving activity, and ameliorated the severity of brain infarction and apoptosis seen in the mice by diminishing pathological changes such as the extensive breakdown of the blood-brain barrier (BBB), nitrosative stress, and the activation of an inflammatory transcriptional factor p65 nuclear factor-kappa B (NF-κB) and a pro-apoptotic kinase p25/Cdk5. SalA also intensively limited cortical infarction and promoted the expression of neurogenesis protein near the peri-infarct cortex and subgranular zone of the hippocampal dentate gyrus by compromising the activation of GSK3ß and p25/Cdk5, which in turn upregulated ß-catenin, doublecortin (DCX), and Bcl-2, most possibly through the activation of PI3K/Akt signaling via the upregulation of brain-derived neurotrophic factor. We conclude that SalA blocks inflammatory responses by impairing NF-κB signaling, thereby limiting inflammation/nitrosative stress and preserving the integrity of the BBB; SalA also concomitantly promotes neurogenesis-related protein expression by compromising GSK3ß/Cdk5 activity to enhance the expression levels of ß-catenin/DCX and Bcl-2 for neuroprotection.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/farmacologia , Isquemia Encefálica/tratamento farmacológico , Ácidos Cafeicos/farmacologia , Lactatos/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Isquemia Encefálica/genética , Isquemia Encefálica/mortalidade , Isquemia Encefálica/patologia , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Quinase 5 Dependente de Ciclina/genética , Quinase 5 Dependente de Ciclina/metabolismo , Modelos Animais de Doenças , Proteínas do Domínio Duplacortina , Proteína Duplacortina , Esquema de Medicação , Regulação da Expressão Gênica , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Injeções Intravenosas , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Neurogênese/efeitos dos fármacos , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/mortalidade , Traumatismo por Reperfusão/patologia , Transdução de Sinais , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/patologia , Análise de Sobrevida , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
17.
J Ethnopharmacol ; 173: 370-82, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26239152

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Four traditional Chinese herbal remedies (CHR) including Buyang Huanwu decoction (BHD), Xuefu Zhuyu decoction (XZD), Tianma Gouteng decoction (TGD) and Shengyu decoction (SYD) are popular used in treating brain-related dysfunction clinically with different syndrome/pattern based on traditional Chinese medicine (TCM) principles, yet their neuroprotective mechanisms are still unclear. MATERIALS AND METHODS: Mice were subjected to an acute ischemic stroke to examine the efficacy and molecular mechanisms of action underlying these CHR. RESULTS: CHR treatment significantly enhanced the survival rate of stroke mice, with BHD being the most effective CHR. All CHR were superior to recombinant tissue-type plasminogen activator (rt-PA) treatment in successfully ameliorating brain function, infarction, and neurological deficits in stroke mice that also paralleled to improvements in blood-brain barrier damage, inflammation, apoptosis, and neurogenesis. Transcriptome analyses reveals that a total of 774 ischemia-induced probe sets were significantly modulated by four CHR, including 52 commonly upregulated genes and 54 commonly downregulated ones. Among them, activation of neurogenesis-associated signaling pathways and down-regulating inflammation and apoptosis pathways are key common mechanisms in ischemic stroke protection by all CHR. Besides, levels of plasma CX3CL1 and S100a9 in patients could be used as biomarkers for therapeutic evaluation before functional recovery could be observed. CONCLUSION: Our results suggest that using CHR, a combinatory cocktail therapy, is a better way than rt-PA for treating cerebral ischemic-associated diseases through modulating a common as well as a specific group of genes/pathways that may partially explain the syndrome differentiation and treatment principle in TCM.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Animais , Calgranulina B/genética , Quimiocina CXCL1/genética , Quimioterapia Combinada , Medicamentos de Ervas Chinesas/farmacologia , Perfilação da Expressão Gênica , Infarto da Artéria Cerebral Média/genética , Masculino , Medicina Tradicional Chinesa , Camundongos Endogâmicos ICR , Neurogênese/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fitoterapia
18.
Biochem Pharmacol ; 67(12): 2251-62, 2004 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15163556

RESUMO

Taxifolin has been reported to down-regulate the expression of intercellular adhesion molecule-1 (ICAM-1), a receptor-mediating firm adhesion with beta2 integrin (e.g., Mac-1) expressed on leukocytes. To evaluate whether taxifolin could modulate Mac-1-dependent firm adhesion by neutrophils, and the possible mechanism(s) underlying its anti-inflammatory action, its effects on N-formyl-methionyl-leucyl-phenylalanine (fMLP) or phorbol-12-myristate-13-acetate (PMA)-activated peripheral human neutrophils were studied. Pretreatment with taxifolin (1-100 microM) concentration-dependently diminished fMLP- or (PMA)-induced Mac-1-dependent firm adhesion and upexpression of surface Mac-1. Mobilisation of intracellular calcium and production of reactive oxygen species (ROS) signal the upexpression of Mac-1 and firm adhesion by neutrophils. Taxifolin impeded the calcium influx induced by fMLP (a receptor-mediated activator) or AlF(4)(-) (a G protein-mediated activator). Taxifolin also effectively inhibited the fMLP- or PMA-induced ROS production with 50% inhibitory concentration (IC(50)) less than 10microM, possibly through impairing the activation of NADPH oxidase, a major ROS-generating enzyme in neutrophils, by restricting the activation of p38 mitogen-activated protein kinase (p38 MAPK) and protein kinase C (PKC). In conclusion, we propose that impairment of ROS production by NADPH oxidase through interfering with p38 MAPK- and/or PKC-dependent signals, and antagonism of G protein-mediated calcium influx may account for the inhibition of Mac-1-dependent neutrophil firm adhesion that confers taxifolin the anti-inflammatory activity.


Assuntos
Flavonóis/farmacologia , Proteínas de Ligação ao GTP/metabolismo , Antígeno de Macrófago 1/metabolismo , NADPH Oxidases/metabolismo , Neutrófilos/efeitos dos fármacos , Quercetina/análogos & derivados , Quercetina/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Cálcio/metabolismo , Adesão Celular , Moléculas de Adesão Celular/metabolismo , Ativação Enzimática/efeitos dos fármacos , Radicais Livres/metabolismo , Humanos , Proteínas Quinases Ativadas por Mitógeno , Neutrófilos/citologia , Proteína Quinase C/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima , Xantina Oxidase/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno
19.
Biochem Pharmacol ; 87(3): 502-14, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24342702

RESUMO

2-Methoxystypandrone (2-MS), a naphthoquinone, has been shown to display an immunomodulatory effect in a cellular model. To explore whether 2-MS could protect mice against cerebral ischemic/reperfusion (I/R)-induced brain injury, we evaluated 2-MS's protective effects on an acute ischemic stroke by inducing a middle cerebral artery occlusion/reperfusion (MCAO) injury in murine model. Treatment of mice that have undergone I/R injury with 2-MS (10-100 µg/kg, i.v.) at 2 h after MCAO enhanced survival rate and ameliorated neurological deficits, brain infarction, neural dysfunction and massive oxidative stress, due to an enormous production of free radicals and breakdown of blood-brain barrier (BBB) by I/R injury; this primarily occurred with extensive infiltration of CD11b-positive inflammatory cells and upexpression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 and p65 nuclear factor-kappa B (NF-κB). All of these pathological changes were diminished by 2-MS; 2-MS also intensively limited cortical infarction and promoted upexpression of neurodevelopmental genes near peri-infarct cortex and endogenous neurogenesis near subgranular zone of hippocampal dentate gyrus and the subventricular zone, most possibly by inactivation of GSK3ß which in turn upregulating ß-catenin, Bcl-2 adam11 and adamts20. We conclude that 2-MS blocks inflammatory responses by impairing NF-κB signaling to limit the inflammation and oxidative stress for preservation of BBB integrity; 2-MS also concomitantly promotes neurodevelopmental protein expression and endogenous neurogenesis through inactivation of GSK3ß to enhance ß-catenin signaling for upexpression of neuroprotective genes and proteins.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Naftoquinonas/farmacologia , Neurogênese/efeitos dos fármacos , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Antígeno CD11b/genética , Antígeno CD11b/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Proteína Duplacortina , Regulação da Expressão Gênica/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Leucócitos/citologia , Leucócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estrutura Molecular , Naftoquinonas/química , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Traumatismo por Reperfusão , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo
20.
J Tradit Complement Med ; 3(4): 240-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24716184

RESUMO

Sheng Yu Decoction ( Shèng Yù Tang; SYD) is a popular traditional Chinese medicine (TCM) remedy used in treating cardiovascular and brain-related dysfunction clinically; yet, its neuroprotective mechanisms are still unclear. Here, mice were subjected to an acute ischemic stroke to examine the efficacy and mechanisms of action of SYD by an integrated neurofunctional and transcriptome analysis. More than 80% of the mice died within 2 days after ischemic stroke with vehicle treatment. Treatments with SYD (1.0 g/kg, twice daily, orally or p.o.) and recombinant thrombolytic tissue plasminogen activator (rt-PA; 10 mg/kg, once daily, intravenously or i.v.) both significantly extended the lifespan as compared to that of the vehicle-treated stroke group. SYD successfully restored brain function, ameliorated cerebral infarction and oxidative stress, and significantly improved neurological deficits in mice with stroke. Molecular impact of SYD by a genome-wide transcriptome analysis using brains from stroke mice showed a total of 162 out of 2081 ischemia-induced probe sets were significantly influenced by SYD. Mining the functional modules and genetic networks of these 162 genes revealed a significant upregulation of neuroprotective genes in Wnt receptor signaling pathway (3 genes) and regulation of cell communication (7 genes) and downregulation of destructive genes in response to stress (13 genes) and in the induction of inflammation (5 genes), cytokine production (4 genes), angiogenesis (3 genes), vasculature (6 genes) and blood vessel (5 genes) development, wound healing (7 genes), defense response (7 genes), chemotaxis (4 genes), immune response (7 genes), antigen processing and presenting (3 genes), and leukocyte-mediated cytotoxicity (2 genes) by SYD. Our results suggest that SYD could protect mice against ischemic stroke primarily through significantly downregulating the damaging genes involved in stress, inflammation, angiogenesis, blood vessel formation, immune responses, and wound healing, as well as upregulating the genes mediating neurogenesis and cell communication, which make SYD beneficial for treating ischemic stroke.

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