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The development of next-generation sequencing (NGS) opens opportunities for new applications such as liquid biopsy, in which tumor mutation genotypes can be determined by sequencing circulating tumor DNA after blood draws. However, with highly diluted samples like those obtained with liquid biopsy, NGS invariably introduces a certain level of misclassification, even with improved technology. Recently, there has been a high demand to use mutation genotypes as biomarkers for predicting prognosis and treatment selection. Many methods have also been proposed to build classifiers based on multiple loci with machine learning algorithms as biomarkers. How the higher misclassification rate introduced by liquid biopsy will affect the performance of these biomarkers has not been thoroughly investigated. In this paper, we report the results from a simulation study focused on the clinical utility of biomarkers when misclassification is present due to the current technological limit of NGS in the liquid biopsy setting. The simulation covers a range of performance profiles for current NGS platforms with different machine learning algorithms and uses actual patient genotypes. Our results show that, at the high end of the performance spectrum, the misclassification introduced by NGS had very little effect on the clinical utility of the biomarker. However, in more challenging applications with lower accuracy, misclassification could have a notable effect on clinical utility. The pattern of this effect can be complex, especially for machine learning-based classifiers. Our results show that simulation can be an effective tool for assessing different scenarios of misclassification.
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OBJECTIVES: Delayed encephalopathy after acute carbon monoxide poisoning (DEACMP) is the most severe complication of carbon monoxide poisoning, which seriously endangers patients' quality of life. This study aims to investigate the efficacy of hyperbaric oxygen (HBO2) on improving dementia symptoms in patients with DEACMP. METHODS: A retrospective analysis was performed on DEACMP patients, who visited Xiangya Hospital, Central South University from June 2014 to June 2020. Among them, patients who received conventional drug treatment combined with HBO2 treatment were included in an HBO2 group, while those who only received conventional drug treatment were included in a control group. HBO2 was administered once daily. Patients in the HBO2 group received 6 courses of treatment, with each course consisting of 10 sessions. The Hasegawa Dementia Scale (HDS) was used to diagnose dementia, and the Clinical Dementia Rating (CDR) was used to grade the severity of dementia for DEACMP. The Alzheimer's Disease Assessment Scale-Cognitive Section (ADAS-Cog), the Functional Activities Questionnaire (FAQ), the Neuropsychiatric Inventory (NPI), and the Clinician's Interview-Based Impression of Change-Plus Caregiver Input (CIBIC-Plus) were performed to assess cognitive function, ability to perform activities of daily living (ADL), behavioral and psychological symptoms, and overall function. The study further analyzed the results of objective examinations related to patients' dementia symptoms, including magnetic resonance imaging detection of white matter lesions and abnormal electroencephalogram (EEG). The changes of the above indicators before and after treatment, as well as the differences between the 2 groups after treatment were compared. RESULTS: There was no significant difference in the HDS score and CDR grading between the 2 groups before treatment (both P>0.05). After treatment, the score of ADAS-Cog, FAQ, NPI, and CIBIC Plus grading of the 2 groups were significantly improved, and the improvement of the above indicators in the HBO2 group was greater than that in the control group (all P<0.05). The effective rate of the HBO2 group in treating DEACMP was significantly higher than that of the control group (89.47% vs 65.87%, P<0.05). The objective examination results (white matter lesions and abnormal EEG) showed that the recovery of patients in the HBO2 group was better than that in the control group. CONCLUSIONS: Hyperbaric oxygen can significantly relieve the symptoms of dementia in patients with DEACMP.
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Encefalopatias , Intoxicação por Monóxido de Carbono , Demência , Oxigenoterapia Hiperbárica , Humanos , Atividades Cotidianas , Intoxicação por Monóxido de Carbono/complicações , Intoxicação por Monóxido de Carbono/terapia , Qualidade de Vida , Estudos Retrospectivos , Oxigênio , Encefalopatias/etiologia , Encefalopatias/terapia , Demência/etiologia , Demência/terapiaRESUMO
Titanium phosphorus oxides (TiPOs) are promising energy-conversion materials, but most are of tetravalent titanium (TiIV), with the trivalent TiIIIPOs less explored because of instability and obstacles in synthesis. In this study, we used a simple synthetic strategy and prepared three new TiIIIPOs with different phosphorus oxoanions: the phosphate Ca2Ti(HPO4)2(PO4)·H2O (1), the phosphite CaTi2(H2O)(HPO3)4·H2O (2), and the hypophosphite Ti(H2PO2)3 (3). Each possesses different structures in one, two, and three dimensions, yet they are related to one another because of their infinite chains. Compound 1 exhibits proton-coupled electron transfer (PCET) reactivity in a solid state, losing one proton from its own HPO4 in oxidation to yield Ca2Ti(HPO4)(PO4)2·H2O (designated as 1O), while compound 2 also exhibits PCET reactivity in which the octahedral core [TiIII(H2O)]3+ gives off two protons to become a titanyl unit [TiIVâO]2+ under oxidation, yielding CaTi2O(HPO3)4·H2O (2O). Both 1O and 2O retain their original frameworks from before oxidation, but there are some changes in the hydrogen and Ti-O bonds that affect the IR absorption and powder X-ray diffraction patterns. Compound 3 represents the first titanium hypophosphite, and two polymorphs were discovered that show structures related to 1 and 2. This work demonstrates a simple strategy that is effective for preparing titanium(III) compounds in a pure phase; further, new findings in the pathways of solid-state PCET reactions promote a greater understanding of the self-sustaining oxidation behavior for TiIIIPO solid materials.
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New technologies for novel biomarkers have transformed the field of precision medicine. However, in applications such as liquid biopsy for early tumor detection, the misclassification rates of next generation sequencing and other technologies have become an unavoidable feature of biomarker development. Because initial experiments are usually confined to specific technology choices and application settings, a statistical method that can project the performance metrics of other scenarios with different misclassification rates would be very helpful for planning further biomarker development and future trials. In this article, we describe an approach based on an extended version of simulation extrapolation (SIMEX) to project the performance of biomarkers measured with varying misclassification rates due to different technological or application settings when experimental results are only available from one specific setting. Through simulation studies for logistic regression and proportional hazards models, we show that our proposed method can be used to project the biomarker performance with good precision when switching from one to anther technology or application setting. Similar to the original SIMEX model, the proposed method can be implemented with existing software in a straightforward manner. A data analysis example is also presented using a lung cancer data set and performance metrics for two gene panel based biomarkers. Results demonstrate that it is feasible to infer the potential implications of using a range of technologies or application scenarios for biomarkers with limited human trial data.
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Medicina de Precisão , Projetos de Pesquisa , Biomarcadores , Simulação por Computador , Humanos , Modelos de Riscos ProporcionaisRESUMO
This study was designed to evaluate the anti-inflammatory effects of Alpinia officinarum Hance extract (AOE) and identify its main active ingredients. AOE was obtained using a 95% ethanol extraction method. Lipopolysaccharide (LPS) were used to induce an inflammatory response in RAW264.7 cells. The results showed that AOE exerts anti-inflammatory effects via inhibition of prostaglandin E2 secretion and cyclooxygenase -2 (COX-2) production. We further analyzed the components of AOE using high-performance liquid chromatography and found that AOE is comprised of several bioactive flavonoids including quercetin (Q), kaempferol (K), galangin (G), and curcumin (C). These four flavonoids effectively inhibited nitric oxide (NO), interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α production. Moreover, they reduced COX-2 and inducible NO synthase expressions via regulation of nuclear factor kappa-light-chain-enhancer of activated B cells and c-Jun N-terminal kinase signaling pathways. Furthermore, we compared and contrasted the anti-inflammatory effects and mechanisms of these four flavonoids at the same dose in the LPS-induced cell inflammation model. The results showed that C is the most effective inhibitor of LPS-induced NO production. However, only Q and K effectively attenuated LPS-induced extracellular signal-regulated kinase and p38 elevations. In conclusion, AOE and its major bioactive compounds exert anti-inflammatory effects on LPS-induced inflammation. As A. officinarum Hance is much cheaper than any of its four flavonoids, especially G, we suggest using AOE as an anti-inflammatory agent.
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Alpinia , NF-kappa B , Alpinia/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Ciclo-Oxigenase 2 , Lipopolissacarídeos , Macrófagos , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico , Óxido Nítrico Sintase Tipo IIRESUMO
T helper (Th)2 cytokines such as interleukin (IL)-4 and IL-13 control immune function by acting on leukocytes. They also regulate multiple responses in non-hematopoietic cells. During pregnancy, IL-4 and IL-13 facilitate alveologenesis of mammary glands. This particular morphogenesis generates alveoli from existing ducts and requires substantial cell proliferation. Using 3D cultures of primary mouse mammary epithelial cells, we demonstrate that IL-4 and IL-13 promote cell proliferation, leading to enlargement of mammary acini with partially filled lumens. The mitogenic effects of IL-4 and IL-13 are mediated by STAT6 as inhibition of STAT6 suppresses cell proliferation and improves lumen formation. In addition, IL-4 and IL-13 stimulate tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1). Prolonged treatment with these cytokines leads to increased IRS-1 abundance, which, in turn, amplifies IL-4- and IL-13-stimulated IRS-1 tyrosine phosphorylation. Through signaling crosstalk between IL-4/IL-13 and insulin, a hormone routinely included in mammary cultures, IRS-1 tyrosine phosphorylation is further enhanced. Lowering IRS-1 expression reduces cell proliferation, suggesting that IRS-1 is involved in IL-4- and IL-13-stimulated cell proliferation. Thus, a Th2-dominant cytokine milieu during pregnancy confers mammary gland development by promoting cell proliferation.
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Técnicas de Cultura de Células em Três Dimensões/métodos , Células Epiteliais/citologia , Proteínas Substratos do Receptor de Insulina/metabolismo , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Glândulas Mamárias Animais/citologia , Fator de Transcrição STAT6/metabolismo , Animais , Proliferação de Células , Células Epiteliais/metabolismo , Feminino , Glândulas Mamárias Animais/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Modelos Animais , Fosforilação , Gravidez , Transdução de SinaisRESUMO
To study the epigenetic gene silencing, yeast is an excellent model organism. Sir proteins are required for the formation of silent heterochromatin. Sir2 couples histone deacetylation and NAD hydrolysis to generate an endogenous epigenetic metabolic small molecule, O-acetyl-ADP-ribose (AAR). AAR is involved in the conformational change of SIR complexes, modulates the formation of SIR-nucleosome preheterochromatin and contributes to the spreading of SIR complexes along the chromatin fiber to form extended silent heterochromatin regions. Here, we show that AAR is capable of enhancing the chromatin silencing effect under either an extra exogenous AAR or a defect AAR metabolic enzyme situation, but decreasing the chromatin silencing effect under a defect AAR synthetic enzyme state. Our results provide an evidence of biological function importance of AAR. It is indicated that AAR does not only function in vitro but also play a role in vivo to increase the effect of heterochromatin epigenetic gene silencing. However, further investigations of AAR are warranted to expand our knowledge of epigenetics and associated small molecules.
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Cromatina/genética , O-Acetil-ADP-Ribose/genética , O-Acetil-ADP-Ribose/metabolismo , Cromatina/fisiologia , Epigênese Genética/genética , Epigenômica/métodos , Inativação Gênica/fisiologia , Heterocromatina/metabolismo , Histonas/metabolismo , Nucleossomos/metabolismo , O-Acetil-ADP-Ribose/fisiologia , Processamento de Proteína Pós-Traducional/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/metabolismo , Sirtuína 2/genética , Sirtuína 2/metabolismo , Sirtuínas/genética , Sirtuínas/metabolismoRESUMO
There is a growing body of evidence that peripheral artery disease (PAD) may be impacted by depression. The objective of this study is to determine whether outcomes, primarily major amputation, differ between patients with depression and those without who presented to hospitals with critical limb ischemia (CLI), the end-stage of PAD. A retrospective cohort of patients hospitalized for CLI during 2012 and 2013 was identified from the National Inpatient Sample (NIS) using ICD-9 codes. The primary outcome was major amputation and secondary outcomes were length of stay and other complications. The sample included 116,008 patients hospitalized for CLI, of whom 10,512 (9.1%) had comorbid depression. Patients with depression were younger (64 ± 14 vs 67 ± 14 years, p < 0.001) and more likely to be female (55% vs 41%, p < 0.001), white (73% vs 66%, p < 0.001), and tobacco users (46% vs 41%, p < 0.001). They were also more likely to have prior amputations (9.8% vs 7.9%, p < 0.001). During the hospitalization, the rate of major amputation was higher in patients with comorbid depression (11.5% vs 9.1%, p < 0.001). In multivariable analysis, excluding patients who died prior to/without receiving an amputation (n = 2621), comorbid depression was associated with a 39% increased odds of major amputation (adjusted OR 1.39, 95% CI 1.30, 1.49; p < 0.001). Across the entire sample, comorbid depression was also independently associated with a slightly longer length of stay (ß = 0.199, 95% CI 0.155, 0.244; p < 0.001). These results provide further evidence that depression is a variable of interest in PAD and surgical quality databases should include mental health variables to enable further study.
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Amputação Cirúrgica , Depressão/epidemiologia , Isquemia/cirurgia , Doença Arterial Periférica/cirurgia , Afeto , Idoso , Idoso de 80 Anos ou mais , Amputação Cirúrgica/efeitos adversos , Amputação Cirúrgica/mortalidade , Comorbidade , Estado Terminal , Bases de Dados Factuais , Depressão/diagnóstico , Depressão/mortalidade , Depressão/psicologia , Feminino , Humanos , Pacientes Internados , Isquemia/diagnóstico , Isquemia/mortalidade , Salvamento de Membro , Masculino , Saúde Mental , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/mortalidade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Estados Unidos/epidemiologiaRESUMO
The traditional rule-based design, 3 + 3, has been shown to be less likely to achieve the objectives of dose-finding trials when compared with model-based designs. We propose a new rule-based design called i3 + 3, which is based on simple but more advanced rules that account for the variabilities in the observed data. We compare the operating characteristics for the proposed i3 + 3 design with other popular phase I designs by simulation. The i3 + 3 design is far superior than the 3 + 3 design in trial safety and the ability to identify the true MTD. Compared with model-based phase I designs, i3 + 3 also demonstrates comparable performances.
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Ensaios Clínicos Fase I como Assunto/métodos , Ensaios Clínicos Fase I como Assunto/estatística & dados numéricos , Simulação por Computador/estatística & dados numéricos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Projetos de Pesquisa/estatística & dados numéricos , Algoritmos , Estudos de Coortes , Relação Dose-Resposta a Droga , Humanos , Preparações Farmacêuticas/administração & dosagemRESUMO
In Saccharomyces cerevisiae, Sir proteins mediate heterochromatin epigenetic gene silencing. The assembly of silent heterochromatin requires histone deacetylation by Sir2, conformational change of SIR complexes, and followed by spreading of SIR complexes along the chromatin fiber to form extended silent heterochromatin domains. Sir2 couples histone deacetylation and NAD hydrolysis to generate an epigenetic metabolic small molecule, O-acetyl-ADP-ribose (AAR). Here, we demonstrate that AAR physically associates with Sir3 and that polySir3-AAR formation has a specific and essential role in the assembly of silent SIR-nucleosome pre-heterochromatin filaments. Furthermore, we show that AAR is capable of stabilizing binding of the Sir3 BAH domain to the Sir3 carboxyl-terminal region. Our data suggests that for the assembly of SIR-nucleosome pre-heterochromatin filament, the structural rearrangement of SIR-nucleosome is important and result in creating more stable interactions of Sir3, such as the inter-molecule Sir3-Sir3 interaction, and the Sir3-nucleosome interaction within the filaments. In conclusion, our results reveal the importance of AAR, indicating that it not only affects the conformational rearrangement of SIR complexes but also might function as a critical fine-tuning modulatory component of yeast silent SIR-nucleosome pre-heterochromatin by stabilizing the intermolecular interaction between Sir3 N- and C-terminal regions.
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Heterocromatina/metabolismo , Nucleossomos/metabolismo , O-Acetil-ADP-Ribose/metabolismo , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/metabolismo , Epigênese Genética , Ligação Proteica , Conformação Proteica , Estabilidade Proteica , Saccharomyces cerevisiae/metabolismo , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/química , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/genética , Sirtuína 2/genética , Sirtuína 2/metabolismoRESUMO
BACKGROUND: Coronary revascularization with bilateral internal mammary arteries is associated with increased long-term survival, but underutilized due to sternal wound infection concerns. Dedicated bilateral mammary grafting programs are typically high-volume academic or private practices, rather than lower-volume federal institutions whose results are not captured in the Society of Thoracic Surgeons database. Our institution used only single internal mammary arterial grafting in the year prior to implementing a dedicated bilateral grafting program using skeletonized technique. We describe our experience transitioning to bilateral mammary grafting and its impact on sternal wound infection. METHODS: Retrospective cohort study at San Francisco Veterans Affairs Medical Center in 200 patients undergoing first-time isolated, multi-vessel coronary artery bypass from August 2014 to October 2017. Sternal wound infection was defined broadly to include any patient receiving antibiotics for suspicion of sternal infection. Patients were followed for wound complications until 3 post-operative months. RESULTS: Of 200 total patients, 45.5% (n=91) were diabetic, 44% (n=88) had BMI >30, and 61.5% (n=123) underwent bilateral mammary grafting. Bilateral mammary grafting population had 2.4% (n=3/123) deep sternal wound infection with 1.6% (n=2/123) requiring sternal reconstruction while single mammary population had 1.3% (n=1/77, p=1.0). Bilateral mammary grafting population had 6.5% (n=8/123) superficial sternal wound infection compared to 5.2% (n=4/77, p=0.77) in single mammary grafting population. CONCLUSIONS: Transitioning to high rates of bilateral mammary utilization was possible in a year with low rates of complications. Based on our experience, surgeons should consider adopting a skeletonized bilateral mammary grafting approach given potential long-term survival benefit.
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While 2-in-1 designs give a flexibility to make a clinical trial either an information generation Phase 2 trial or a full scale confirmatory Phase 3 trial, flexible sample size designs can naturally fit into the 2-in-1 design framework. This study is to show that the CHW design can be blended into a 2-in-1 design to improve the adaptive performance of the design. Commenting on the usual 2-in-1 design, we demonstrated that the CHW design can achieve the goal of a 2-in-1 design with satisfactory statistical power and efficient average sample size for a targeted range of the treatment effect.
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Projetos de Pesquisa , Tamanho da AmostraRESUMO
Lipopolysaccharide (LPS) released from gram-negative bacteria stimulates immune responses in infected cells. Epigenetic modifications such as DNA methylation and protein methylation modulate LPS-induced innate immune gene expressions. Expression of the Klotho protein decreased with LPS treatment in rats. In a cellular model, information regarding the effect of LPS on Klotho expression was meager. In the present study, we demonstrated that LPS triggered global DNA and protein methylation in glomerular mesangial MES-13 cells. LPS upregulated protein expressions of enzymes central to cellular methylation reactions, especially protein arginine methyltransferase 6 (PRMT6) in MES-13 cells. Expression of the Klotho protein was diminished by LPS and was restored by 5-Aza-2'-deoxycytidine (5-Aza-2'-dc), AMI-1, and ammonium pyrrolidinedithiocarbamate (PDTC), but not adenosine aldehyde (AdOx). NF-κB was identified as a substrate for arginine methylation and interacted with PRMT6 in MES-13 cells. Inhibition of PRMT activity by AMI-1 blocked LPS-induced NF-κB nuclear translocation in MES-13 cells. Our data indicate that NF-κB negatively regulated Klotho expression with an interaction with PRMT6, which was upregulated by LPS in MES-13 cells.
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Glucuronidase/metabolismo , Lipopolissacarídeos/farmacologia , Células Mesangiais/citologia , NF-kappa B/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Animais , Células Cultivadas , Metilação de DNA , Epigênese Genética , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Klotho , Células Mesangiais/efeitos dos fármacos , Células Mesangiais/metabolismo , Metilação , Camundongos , Regulação para CimaRESUMO
In searching for practical crystalline porous solids, two unique hybrid materials with featured functions, In-bpy and In-dpe, were prepared without deliberately designed organic linker units or complex post-modification procedures. Composed of oxalate-embedded metal phosphite (MPO) sheets and bipyridyl-type ligands of varied molecular lengths, they show a common pillar-layered topology but are the first well-characterized organo-MPOs to possess genuine porosity, substantiated by CO2 adsorption, and structural stability under harsh conditions. In-bpy exhibits a turn-on fluorescence signal when in contact with p-xylene, making it the first MPO-based sensing material with selectivity and recyclability. Furthermore, In-dpe demonstrates a facile and unprecedented route to the superhydrophobicity of porous solids via a [2+2] photocycloaddition reaction between linker and foreign units. Our findings suggest that MPO may serve as a promising platform for hybrid frameworks to create many more functional porous materials.
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Eucalyptus globulus possesses important pharmacological activities, including antioxidant and anti-inflammatory effects. We investigated the anti-fatigue, antioxidant, and anti-inflammatory effects of eucalyptus essential oil after swimming exercise using an animal model. Male Sprague Dawley rats were administered eucalyptus oil (200 µL/h) daily via inhalation (15 min), and anti-fatigue effects were assessed following eucalyptus essential oil administration for 2 or 4 weeks when forced to swim until exhaustion while carrying ~5% body weight-equivalent. To assess antioxidant and anti-inflammatory effects, control and oil-treated groups were subjected to swimming, which was intensified from 90 min to 120 min daily over 4 weeks, with non-swimming groups included as controls. The 2- and 4-week-treated rats increased their swimming-to-exhaustion time by 46 s and 111 s, respectively. Additionally, lactate (LA), creatine kinase (CK), and lactate dehydrogenase (LDH) activities increased significantly in the non-treated swimming relative to levels observed in the non-swimming groups (P < 0.05); however, no significant differences in these markers were observed between the treated groups. The anti-fatigue effects were related to LA clearance and reduced LDH and CK concentrations. Moreover, compared to the corresponding levels in the non-swimmers, the non-treated swimmers showed markedly elevated levels of liver malondialdehyde (MDA), xanthine oxidase (XO), and other factors, but significantly decreased (P < 0.05) glutathione (GSH) concentrations. However, compared with that of the non-swimmer group, the treated swimming group showed no significant changes in these levels (P > 0.05), suggesting stable XO and MDA production and maintenance of GSH levels. These results suggested that eucalyptus oil aromatherapy increased rat swimming performance and antioxidant capacity and decreased oxidative damage and inflammatory reactions in tissues, indicating good anti-fatigue, antioxidant, and anti-inflammatory effects after high-intensity endurance exercise.
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Aromaterapia , Animais , Anti-Inflamatórios , Antioxidantes , Óleo de Eucalipto , Fadiga , Masculino , Condicionamento Físico Animal , Ratos , Ratos Sprague-Dawley , NataçãoRESUMO
Cisplatin is a chemotherapeutic agent widely used in the treatment of various cancers. However, cisplatin can induce nephrotoxicity and neurotoxicity, limiting its dosage and usage. Galangin, a natural flavonol, has been found to exhibit anti-oxidant and anti-inflammatory effects in vivo. Here, we investigated the effects of galangin on cisplatin-induced acute kidney injury (AKI) and its molecular mechanisms in mice. Galangin administration reduced the cisplatin-induced oxidative stress by decreasing renal MDA and 3-NT formations. Galangin administration also increased renal anti-oxidative enzyme activities (SOD, GPx, and CAT) and GSH levels depleted by cisplatin. Furthermore, galangin administration inactivated stress-induced Nrf2 protein and its downstream products, HO-1 and GCLC. In terms of the inflammatory response, galangin administration reduced IκBα phosphorylation, NF-κB phosphorylation and nuclear translocation, and then inhibited cisplatin-induced secretions of pro-inflammatory TNF-α, IL-1ß and IL-6. In addition, cisplatin-induced ERK and p38 phosphorylations were inhibited by galangin administration. In terms of cell death, galangin administration reduced levels of p53, pro-apoptotic Bax and activated caspase-3 to inhibit the cisplatin-induced apoptosis. Galangin administration also reduced the expression levels of RIP1 and RIP3 to inhibit cisplatin-induced RIP1/RIP3-dependent necroptosis. Therefore, galangin administration significantly ameliorates cisplatin-induced nephrotoxicity by attenuating oxidative stress, inflammation, and cell death through inhibitions of ERK and NF-κB signaling pathways. Galangin might be a potential adjuvant for clinical cisplatin therapy.
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Injúria Renal Aguda/prevenção & controle , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Cisplatino , Citocinas/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Flavonoides/farmacologia , Mediadores da Inflamação/metabolismo , Rim/efeitos dos fármacos , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/enzimologia , Injúria Renal Aguda/patologia , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Citoproteção , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Glutamato-Cisteína Ligase/metabolismo , Heme Oxigenase-1/metabolismo , Rim/enzimologia , Rim/patologia , Masculino , Malondialdeído/metabolismo , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos BALB C , Fator 2 Relacionado a NF-E2/metabolismo , Fosforilação , Transdução de Sinais/efeitos dos fármacos , Tirosina/análogos & derivados , Tirosina/metabolismoRESUMO
Reproducing inorganic modules in situ for pore augmentation of pure inorganic frameworks is challenging but can be a key to rational synthesis. After the first success of using monoamines of varied lengths as a template in producing a set of building blocks that led to a series of growing channels up to a 72-membered ring (72R), research continued into those building blocks to seek any new topologies from them. In this study, another type of template is reported that can control the same building blocks to repeatedly form in situ. By using long linear-chain bola-type surfactants, two new bimetal phosphites, a monoclinic phase exhibiting remarkable quasi-channels of 1.15â nm and an orthorhombic phase with 28R channels of 1.06â nm have been created. By taking them as the first members, two series of novel topologies can be devised, each having a general formula to predict the size and channel wall compositions.
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In this study, α-TiP layered structure incorporating a heterometal center for organic ligand binding to enhance structural complexity and functionality were prepared. The protons of the α-TiP layer were replaced with zinc ions coordinated by 4-pyridinecarboxylic acid (PCA) and water to form a layer structure, TiZn(PO4 )2 (H2 O)(PCA) (1). The tetrahedral zinc center with coordinated water in 1 is unprecedented in zincophosphate or zinc-MOF systems and is usually only found in metalloenzyme systems. The neutral zincotitanophosphate layers, tightly stacked through hydrogen bonds, showed velcro-like behavior on intercalating 4,4'-trimethylenedipyridine (TMDP) reversibly. It rendered a remarkable luminescence property to 1, emitting blue-to-white light under UV excitation. Surprisingly, the replacement of TMDP for PCA in the hydrothermal synthesis still resulted in 1, plus another structure, Ti4 Zn2 (H2 TPB)(PO4 )4 (HPO4 )4 (H2 PO4 )2 (2) (TPB=1,2,4,5-tetra(4-pyridyl)benzene). Clearly, in situ C-C cracking and C-C coupling of TMDP simultaneously occurred to generate PCA and TPB and thereafter the oxidant, Zn(NO3 )2 , was quantitatively determined to isolate crystal 1 from 2. The structure of 2 also featured α-TiP layers with pedant Zn tetrahedra but formed a three-dimensional neutral framework through TPB. For the first time, α-TiP-derived structures and their properties have been elucidated, which help in understanding intriguing in situ ligand formation and intercalation-induced luminescence, to exploit potential photocatalysis in polymerization.
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The in situ and systematic high-throughput investigation of the system Al3+/4,4'-benzophenonedicarboxylic acid (H2BPDC)/DMF/H2O in the presence of various additives was carried out, and a new Al-MOF of composition [Al(OH)(BPDC)], denoted as CAU-21-BPDC, was obtained. Its crystal structure was determined from single-crystal X-ray diffraction data (space group I422, a = b = 17.2528(7) Å, c = 23.864(1) Å). The structure is built up by octanuclear rings of cis corner-sharing AlO6 polyhedra forming the inorganic building unit (IBU). These {Al8O8} IBUs are arranged in a bcu packing and connected via BPDC2- ions in a way that each IBU is linked via two linker molecules to each of the eight adjacent IBUs. Thus, accessible, one-dimensional modulated pores with a diameter between 3.6 and 6.5 Å are formed. In addition, tetrahedral cavities are formed by the BPDC2- linker molecules. The framework of CAU-21-BPDC is polymorphous with that of CAU-8-BPDC, which contains one-dimensional chains of trans corner-sharing AlO6 polyhedra connected by BPDC2- ions. Replacing H2BPDC by 4,4'-oxydibenzoic acid (H2ODB), which contains an oxygen atom between the phenyl rings instead of a keto group, leads to the synthesis of Al-MOFs isoreticular with CAU-8-BPDC and CAU-21-BPDC. In addition, a coordination polymer, [Al(HODB)2(OH)], was discovered and structurally characterized. The structure of CAU-8-ODB was refined from powder X-ray diffraction data, while a Pawley refinement was carried out for CAU-21-ODB to determine the lattice parameters and confirm phase purity. The structure of CAU-21-ODB was confirmed using density functional theory (DFT) calculations. A thorough characterization shows that the CAU-8 and CAU-21-type structures are stable up to 350 and 300 °C in air, respectively, almost independent of the linker molecules incorporated. The former MOFs are porous toward N2 and CO2, while the latter only adsorb CO2.
RESUMO
In this study, we synthesized a unique inorganic framework bearing the largest 18-membered-ring channels in gallium phosphites, denoted as NTHU-15, which displayed genuine porosity even though large organic templates were present. The idea of using the "template-cladded" strategy succeeded in releasing channel space of up to â¼24% of the unit-cell volume as highly positive-charged organic templates were manipulated to cling to the anionic inorganic walls. NTHU-15 showed both high H2 uptake of 3.8 mmol/g at 77 K and effective CO2 adsorption of â¼2.4 mmol/g at 298 K, which surpassed those of all other known extra-large-channel inorganic framework structures. NTHU-15 has been successful at overcoming the long-standing problem of organic-templated extra-large-channel structures as opposed to a "true open" framework. Moreover, it realized practical gas sorption functionality in innovated metal phosphites. In view of its high stability in hot water and high selectivity for CO2 adsorption, NTHU-15 may be the first novel inorganic framework material to be applied to the field of flue gas cleaning.