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BACKGROUND: Obesity-induced abnormal bone marrow microenvironment is one of the important risk element for bone metastasis in prostate cancer (PCa). The present study aimed to determine whether obesity-induced elevation in palmitic acid (PA), which is the most abundant of the free fatty acids (FFAs), increased CCL2 via the GPRs/KLF7 pathway in bone marrow adipocytes (BMA) to facilitate PCa growth and metastasis. METHODS: We constructed a bone-tumor bearing mouse model with obesity through high-fat diet, and observed the tumor formation ability of PCa cells. In vitro, observe the effect of PA on the expression level of CCL2 in BMA through GPRs/KLF7 signaling pathway. After co-culture of BMA and PCa cells, CCK8 assay and transwell experiment were used to detect the changes in biological behavior of PCa cells stimulated by BMA. RESULTS: The BMA distribution in the bone marrow cavity of BALB/c nude mice fed with the high-fat diet (HFD) was evidently higher than that in the mice fed with the normal diet (ND). Moreover, HFD-induced obesity promoted KLF7/CCL2 expression in BMA and PCa cell growth in the bone marrow cavity of the mice. In the vitro experiment, a conditioned medium with increased CCL2 obtained from the BMA cultured with PA (CM-BMA-PA) was used for culturing the PCa cell lines, which evidently enhanced the proliferation, invasion, and migration ability. KLF7 significantly increased the CCL2 expression and secretion levels in BMA by targeting the promoter region of the CCL2 gene. In addition, GPR40/120 engaged in the PA-induced high KLF7/CCL2 levels in BMA to facilitate the malignant progression of PC-3 cells. CONCLUSIONS: PA-activated GPRs/KLF7/CCL2 pathway in BMA facilitates prostate cancer growth and metastasis.
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Neoplasias Ósseas , Neoplasias da Próstata , Animais , Humanos , Masculino , Camundongos , Adipócitos/metabolismo , Medula Óssea/patologia , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Camundongos Nus , Obesidade/patologia , Ácido Palmítico/farmacologia , Neoplasias da Próstata/patologia , Microambiente TumoralRESUMO
PURPOSE: Based on the comparison of ramucirumab monoclonal antibody with control treatments in randomized controlled trials, this study aims to elucidate the role of ramucirumab monoclonal antibody in cancer therapy and its potential side effects, providing scientific evidence for clinical treatment. METHODS: PubMed, Embase, Cochrane, and Web of Science were searched systematically to obtain the trials on ramucirumab in the treatment of gastric or gastroesophageal junction (GEJ) adenocarcinoma up to April 13, 2023. We included randomized controlled trials (RCTs) evaluating the efficacy and safety of ramucirumab as monotherapy and in combination with other chemotherapy agents as interventions for treating gastric or gastroesophageal junction (GEJ) adenocarcinoma. RESULTS: After screening 2200 studies, we finally included 8 eligible studies (involving a total of 3,283 participants). Meta-analysis results showed that compared to the control group, ramucirumab monotherapy significantly improved overall survival (OS) (hazard ratio [HR] = 0.77, 95% confidence interval [CI] [0.67, 0.89]) and progression-free survival (PFS) (HR = 0.48, 95% CI [0.40, 0.58]). Similar results were obtained for ramucirumab combined with paclitaxel. In the treatment combining ramucirumab with paclitaxel, compared to monotherapy, three severe adverse reactions (grade ≥ 3) were observed with significantly increased risks (OR > 2). These include proteinuria (OR = 5.37, 95% CI [1.22, 23.54]), hypertension (OR = 4.02, 95% CI [2.63, 6.14]), and gastrointestinal perforation (OR = 4.64, 95% CI [1.00, 21.60]). Subgroup analysis further indicated that ramucirumab is effective in both non-East Asian and East Asian populations, with East Asian patients more prone to developing proteinuria, while having a lower incidence of hypertension. Additionally, ramucirumab demonstrated comparable efficacy between first-line and second-line treatments, with a higher incidence of proteinuria observed in second-line therapy. CONCLUSION: Ramucirumab significantly improves the prognosis of patients with gastric or gastroesophageal junction adenocarcinoma. When used in combination with paclitaxel, close monitoring of adverse reactions such as proteinuria (especially in East Asian populations), hypertension (especially in non-East Asian populations), and gastrointestinal perforation is essential.
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Perovskite oxides are promising catalysts for the oxygen evolution reaction, yet the huge chemical space remains largely unexplored due to the lack of effective approaches. Here, we report the distilling of accurate descriptors from multi-source experimental data for accelerated catalyst discovery by using the newly designed method of sign-constrained multi-task learning within the framework of sure independence screening and sparsifying operator that overcomes the challenge of data inconsistency between different sources. While many previous descriptors for the catalytic activity were proposed based on respective small data sets, we obtained a new 2D descriptor (dB, nB) based on 13 experimental data sets collected from different publications. Great universality and predictive accuracy, and the bulk-surface correspondence, of this descriptor have been demonstrated. With this descriptor, hundreds of unreported candidate perovskites with activity greater than the benchmark catalyst Ba0.5Sr0.5Co0.8Fe0.2O3 were identified from a large chemical space. Our experimental validations on five candidates confirmed the three highly active perovskite catalysts SrCo0.6Ni0.4O3, Rb0.1Sr0.9Co0.7Fe0.3O3, and Cs0.1Sr0.9Co0.4Fe0.6O3. This work provides an important new approach in dealing with inconsistent multi-source data for applications in the field of data-driven catalysis and beyond.
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Obesity is a high-risk factor in the development of endometrial cancer (EC). Our previous study observed that miR-548ag was significantly overexpressed in the sera of obese individuals. Here, we report the function of miR-548ag and its mechanism in promoting the obesity-related progression of EC. The content of miR-548ag was increased in the serum of obese EC individuals. Bioinformatics analysis indicated that the survival rate of EC patients with a higher expression of miR-548ag was significantly reduced. The Mps One Binder Kinase Activator 1B (MOB1B, the core member of the Hippo signaling pathway) is a direct target gene of miR-548ag, which is inversely correlated with the expression of miR-548ag. The overexpression of miR-548ag enhances the proliferation, invasion, and migration, and inhibits apoptosis by downregulating the expression of MOB1B, leading to the deactivation of the Hippo pathway in EC cell lines and contributing to tumor progression in vivo. Our study has established that miR-548ag functions as an oncogene by suppressing MOB1B in the development of obesity-related EC.
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Neoplasias do Endométrio , MicroRNAs , Feminino , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Proliferação de Células/genética , Oncogenes/genética , Neoplasias do Endométrio/metabolismo , Obesidade/complicações , Obesidade/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação Neoplásica da Expressão GênicaRESUMO
BACKGROUND: In previous study, we found that the content of medium-chain fatty acid Caprylic Acid (FFA C8:0) may be an important risk factor of obesity induced prostate cancer (PCa). However, the relationship between FFA C8:0 and PCa has not been reported. In this study, we explored whether the FFA C8:0 can promotes the progression of PCa by up-regulating Krüppel-like factor 7 (KLF7). METHODS: We collected tissues from PCa patients and Benign Prostate Hyperplasia (BPH), constructed a primary-tumor bearing mouse model with obesity through high-fat diet, and observed the tumor formation ability of PCa cells. In vitro, CCK8 assay, plate cloning, Transwell and scratch experiment were used to detect the changes in biological behavior of PCa cells stimulated by FFA C8:0. RESULTS: First, we found that the expression level of KLF7 is higher in PCa tissues of patients, and the expression of KLF7 is positively correlated with tumour-promoting gene IL-6, while it is negative correlated with another tumour-suppressor gene p21. Then, this study found that PCa cells were more likely to form tumors in diet induced obese mice. Compared with the normal diet group (ND), the expression levels of KLF7 in tumor tissues in high-fat diet group (HFD) were higher. Futhermore, we verified that high concentrations of FFA C8:0 can promote the biological behavior of PCa cells by activating KLF7/IL-6/p21 signaling pathway, which is mediated by the GPR84. CONCLUSIONS: Our research may provide a potential target for clinical prevention and treatment of PCa which induced by obesity.
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Interleucina-6 , Neoplasias da Próstata , Humanos , Masculino , Camundongos , Animais , Linhagem Celular Tumoral , Neoplasias da Próstata/patologia , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Receptores Acoplados a Proteínas G/genética , Obesidade/complicaçõesRESUMO
Inflammation is a major adverse outcome induced by inhaled particulate matter with a diameter of ≤ 2.5 µm (PM2.5), and a critical trigger of most PM2.5 exposure-associated diseases. However, the key molecular events regulating the PM2.5-induced airway inflammation are yet to be elucidated. Considering the critical role of circular RNAs (circRNAs) in regulating inflammation, we predicted 11 circRNAs that may be involved in the PM2.5-induced airway inflammation using three previously reported miRNAs through the starBase website. A novel circRNA circ_0008553 was identified to be responsible for the PM2.5-activated inflammatory response in human bronchial epithelial cells (16HBE) via inducing oxidative stress. Using a combinatorial model PM2.5 library, we found that the synergistic effect of the insoluble core and loaded Zn2+ ions at environmentally relevant concentrations was the major contributor to the upregulation of circ_0008553 and subsequent induction of oxidative stress and inflammation in response to PM2.5 exposures. Our findings provided new insight into the intervention of PM2.5-induced adverse outcomes.
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MicroRNAs , RNA Circular , Células Epiteliais/metabolismo , Humanos , Inflamação/induzido quimicamente , MicroRNAs/metabolismo , Estresse Oxidativo , Material Particulado/toxicidade , Zinco/toxicidadeRESUMO
GPCRs regulate multiple intracellular signaling cascades. Biasedly activating one signaling pathway over the others provides additional clinical utility to optimize GPCR-based therapies. GPCR heterodimers possess different functions from their monomeric states, including their selectivity to different transducers. However, the biased signaling mechanism induced by the heterodimerization remains unclear. Motivated by the issue, we select an important GPCR heterodimer (µOR/δOR heterodimer) as a case and use microsecond Gaussian accelerated molecular dynamics simulation coupled with potential of mean force and protein structure network (PSN) to probe mechanisms regarding the heterodimerization-induced constitutive ß-arrestin activity and efficacy change of the agonist DAMGO. The results show that only the lowest energy state of the µOR/δOR heterodimer, which adopts a slightly outward shift of TM6 and an ICL2 conformation close to the receptor core, can selectively accommodate ß-arrestins. PSN further reveals important roles of H8, ICL1, and ICL2 in regulating the constitutive ß-arrestin-biased activity for the apo µOR/δOR heterodimer. In addition, the heterodimerization can allosterically alter the binding mode of DAMGO mainly by means of W7.35. Consequently, DAMGO transmits the structural signal mainly through TM6 and TM7 in the dimer, rather than TM3 similar to the µOR monomer, thus changing the efficacy of DAMGO from a balanced agonist to the ß-arrestin-biased one. On the other side, the binding of DAMGO to the heterodimer can stabilize µOR/δOR heterodimers through a stronger interaction of TM1/TM1 and H8/H8, accordingly enhancing the interaction of µOR with δOR and the binding affinity of the dimer to the ß-arrestin. The agonist DAMGO does not change main compositions of the regulation network from the dimer interface to the transducer binding pocket of the µOR protomer, but induces an increase in the structural communication of the network, which should contribute to the enhanced ß-arrestin coupling. Our observations, for the first time, reveal the molecular mechanism of the biased signaling induced by the heterodimerization for GPCRs, which should be beneficial to more comprehensively understand the GPCR bias signaling.
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Transdução de Sinais , Ala(2)-MePhe(4)-Gly(5)-Encefalina/metabolismo , beta-Arrestinas/metabolismo , Dimerização , Membrana Celular/metabolismoRESUMO
BACKGROUND & AIMS: A subset of patients with Crohn's disease (CD) do not respond to ustekinumab at the standard dose of 90 mg every 8 weeks. Little is known about the efficacy of shortening the interval between doses. METHODS: We performed a retrospective study to determine the effectiveness of ustekinumab dose interval shortening, collecting data from 506 patients with CD who received subcutaneous ustekinumab 90 mg every 8 weeks at a single center. We obtained data from 110 patients who initially received subcutaneous ustekinumab 90 mg every 8 weeks and then had their interval shortened to every 4 weeks. Harvey Bradshaw Index (HBI) scores before and after the dose interval shortening was available for 78 patients in the cohort (71%), levels of C-reactive protein (CRP) for 60 patients (55%), and levels of fecal calprotectin for 8 patients (7%). RESULTS: Following dose interval shortening, the patients' median HBI decreased from 4.5 to 3 (P = .002), the median level of CRP decreased from 8 mg/L to 3 mg/L (P = .031), and median level of fecal calprotectin decreased from 378 µg/g to 157 µg/g (P = .57). Among patients who had an HBI >4, a level of CRP ≥5mg/dL, a level of fecal calprotectin >250ug/g, or endoscopic evidence for disease activity before dose interval shortening, after the dose interval was shortened, 28% achieved clinical remission (an HBI score ≤4), 22% had a normal level of CRP (<5 mg/dL), 50% had reduced levels of fecal calprotectin, and 36% achieved endoscopic remission. CONCLUSIONS: Shortening the ustekinumab 90 mg dose interval to 4 weeks for patients with CD who did not respond to doses every 8 weeks improved clinical and biological indices of disease activity. Patients who lose response to the standard dose of ustekinumab might benefit from dose interval shortening, which was effective and safe.
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Doença de Crohn , Ustekinumab , Proteína C-Reativa/metabolismo , Doença de Crohn/tratamento farmacológico , Humanos , Complexo Antígeno L1 Leucocitário , Indução de Remissão , Estudos Retrospectivos , Índice de Gravidade de DoençaRESUMO
SnS2/Na0.9Mg0.45Ti3.55O8 (SNMTO) composite photocatalyst was synthesized by a hydrothermal method. The chemical combination in lattice scale between SnS2 and Na0.9Mg0.45Ti3.55O8 (NMTO) was observed by high-resolution transmission electron microscopy, indicating that heterojunctions were obtained between SnS2 and NMTO. The photocatalytic activity of SNMTO heterojunctions was improved in comparison with that of pure NMTO and SnS2 for the photocatalytic degradation of methylene blue and Rhodamine B. Electrons were excited in n-type semiconductors NMTO and SnS2 under light illumination, and a part of them moved to the interface, determined with the surface potential reduction observed directly by Kelvin probe force microscopy. The charge redistribution in the composite illustrates a high density of interface states between SnS2 and NMTO, which attract lots of photoelectrons, as a result enhancing the photocatalytic performance. This finding is very different from the speculation that the photogenerated electrons and holes migrate from one part to another because it is difficult for charge carriers to travel through the interface with high energy.
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OBJECTIVE: Patients undergoing carotid endarterectomy (CEA) have a significant possibility of developing postoperative cognitive decline (POCD). POCD after surgery could be result from cerebral hypotension induced by cross-clamping or postoperative hyperperfusion. Optic nerve sheath diameter (ONSD) exhibits an excellent correlation with invasive intracranial pressure monitoring, Here, the authors explored the risk factors of POCD in patients undergoing CEA, paying close attention to ONSD to test the hypothesis that decrease of coronal ONSD was related to the incidence of POCD. DESIGN: Observational retrospective review. SETTING: Single tertiary academic center. PARTICIPANTS: One hundred sixteen patients undergoing CEA from January 1, 2019 to December 31, 2019. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: A multivariate logistic regression, scatter diagrams, and a receiver operating curve were used to evaluate the ability to predict POCD though the change in coronal ONSD. This study ultimately enrolled 84 patients and the incidence of POCD within postoperative two days was 28.6%. Decrease of coronal ONSD (odds ratio [OR], 0.438; 95% confidence interval [CI] 0.217-0.881; pâ¯=â¯0.021) and total intravenous anesthesia (TIVA) (OR, 25.541, 95% CI 2.100-310.614, pâ¯=â¯0.011) were independent risk factors for POCD. Changes in coronal ONSD had an area under the curve to distinguish POCD of 0.716 (95% CI 0.531-0.902). Using a cutoff of 0.05 cm, changes of coronal ONSD had a sensitivity of 66.7% and specificity of 66.7%. CONCLUSIONS: Decrease of coronal ONSD, measured by ultrasonography and TIVA, were associated with POCD. Change in coronal ONSD was a moderate predictor of incidence of POCD.
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Endarterectomia das Carótidas , Hipertensão Intracraniana , Complicações Cognitivas Pós-Operatórias , Endarterectomia das Carótidas/efeitos adversos , Humanos , Pressão Intracraniana , Nervo Óptico/diagnóstico por imagem , Estudos Prospectivos , Estudos Retrospectivos , UltrassonografiaRESUMO
Prostate cancer (PCa) continues to be the most common, noncutaneous cancer in men. Bone is the most frequent site of PCa metastases, and up to 90% of patients with advanced PCa develop bone metastases. An altered bone marrow microenvironment, induced by obesity, is a significant mediator for the bone tropism of PCa. However, the specific molecular mechanisms by which obesity causes changes in the bone marrow microenvironment, leading to PCa bone metastasis, are not fully understood. Our results demonstrate that a high-fat diet (HFD) leads to dyslipidemia and changes in bone marrow of nude mice: an increase in the area and number of adipocytes and a reduction in the area and number of osteoblasts. Moreover, a HFD promoted cyclooxygenase 2 (COX2) expression and inhibited osteoprotegerin (OPG) expression in the bone microenvironment. Additionally, the total level of free fatty acids (FFAs) and caprylic acid (C8:0) was significantly higher in PCa patients with bone metastases. In vitro, caprylic acid (C8:0) promoted bone mesenchymal stem cell (MSC)-derived adipocytic differentiation, COX2 expression, and prostaglandin E2 (PGE2) secretion, whereas osteoblastic differentiation and OPG expression were reduced. Furthermore, caprylic acid (C8:0)-treated adipocytes promoted the invasion and migration of PCa cells. Taken together, our findings suggest caprylic acid (C8:0) promotes bone metastasis of PCa by dysregulated adipo-osteogenic balance of bone marrow.
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Adipócitos/efeitos dos fármacos , Adipócitos/patologia , Medula Óssea/efeitos dos fármacos , Medula Óssea/patologia , Neoplasias Ósseas/patologia , Caprilatos/farmacologia , Neoplasias da Próstata/patologia , Adipócitos/metabolismo , Animais , Medula Óssea/metabolismo , Neoplasias Ósseas/metabolismo , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Ciclo-Oxigenase 2/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoblastos/patologia , Células PC-3 , Neoplasias da Próstata/metabolismo , Microambiente Tumoral/efeitos dos fármacosRESUMO
BACKGROUND: Han and Uygur are the two main nationalities living in Xinjiang, China. There are significant differences in the incidence of metabolic diseases for two nationalities, but the specific reasons are not clear. Obesity is an important risk factor for the development of metabolic syndrome, which may be closely related to the increase of serum free fatty acids (FFAs) content. This study aims to use metabolomics to compare the changes of serum FFAs profiles between normal weight (NW) and obese (OB) individuals of two nationalities, screening out the differential FFAs, predicting and evaluating their relationship with diseases. METHODS: Thirty-four kinds of FFAs in serum were detected by ultra-high-pressure liquid chromatography-mass spectrometry (UHPLC-MS) and distinctions in FFAs profiles were evaluated using a metabolomics method while Receiver operating characteristics (ROC) and logistic regression models were used to explore FFAs significant for diagnosing obesity and obesity-associated comorbidities. RESULTS: In the Han nationality, ten kinds of FFAs (C7:0, C8:0, C9:0, C10:0, C11:0, C14:0, C18:2, C20:3, C20:4 and C22:6) showed significant differences between NW and OB individuals. These differential FFAs may be related to hypertension and gestational diabetes mellitus. In the Uygur nationality, C20:3 and C20:5 showed significant differences between NW and OB individuals. C9:0 and C19:0, which were screened out among the female subjects, showed a good ability to predict obesity status in Uygur females (AUC = 0.950). CONCLUSION: In both the Han and Uygur nationalities, the FFAs profiles of NW individuals differed from those of OB individuals. The significantly differential FFAs are closely related to obesity and may be important risk factors for obesity and related metabolic diseases.
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Ácidos Graxos não Esterificados/sangue , Obesidade/sangue , Peso Corporal/fisiologia , China , Cromatografia Líquida de Alta Pressão , Etnicidade , Feminino , Humanos , Modelos Logísticos , Masculino , Curva ROC , Fatores de RiscoRESUMO
Background: Although 7 million copies of Eat Right 4 Your Type have been sold in >60 languages, there has been a lack of evidence supporting the "blood-type" diet hypothesis. Objective: The present study aimed to examine the validity of this diet in overweight adults. Methods: A total of 973 adults [mean ± SEM age: 44.6 ± 0.4 y; mean ± SEM body mass index (BMI; kg/m2): 32.5 ± 0.2; 758 women, 215 men] were participants of the Toronto Healthy Diet Study. A 1-mo, 196-item food-frequency questionnaire was used to determine dietary intakes before and after a 6-mo dietary intervention. Diet scores were calculated to determine relative adherence to each of the 4 blood-type diets as a secondary analysis. ABO blood group was determined by genotyping rs8176719 and rs8176746. ANCOVA was used to compare cardiometabolic risk factors across tertiles of diet scores. Results: At baseline, individuals with a higher adherence score to the type A diet had lower diastolic blood pressure (tertile 3 compared with tertile 1: 70.9 ± 1.1 compared with 73.3 ± 1.1 mm Hg; P < 0.01). Lower waist circumference was observed in individuals with higher adherence to the type B (tertile 3 compared with tertile 1: 100.8 ± 1.8 compared with 105.4 ± 1.7 cm; P < 0.01) and type AB (tertile 3 compared with tertile 1: 101.2 ± 1.8 compared with 104.8 ± 1.7 cm; P < 0.01) diets. After a 6-mo dietary intervention, individuals with increased adherence to the type A and type B diets had greater reductions in BMI and waist circumference, respectively (P < 0.01). Individuals with an increase in type O diet adherence showed decreases in both BMI and waist circumference (P < 0.01). However, matching the diets with the corresponding ABO genotype of each individual did not change the effect size of any of these associations either at baseline or at 6 mo. Conclusions: ABO genotype does not modify any association between blood-type diets and biomarkers of cardiometabolic disease in overweight adults, suggesting that the theory behind this diet is not valid This study was based on the data of a trial that was registered at www.clinicaltrials.gov as NCT00516620.
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Sistema ABO de Grupos Sanguíneos/genética , Índice de Massa Corporal , Doenças Cardiovasculares , Dieta , Genótipo , Obesidade/sangue , Adulto , Biomarcadores , Pressão Sanguínea , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/genética , Inquéritos sobre Dietas , Comportamento Alimentar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/dietoterapia , Obesidade/genética , Sobrepeso , Fatores de Risco , Circunferência da Cintura , Redução de PesoRESUMO
Novel multifeatured hollandite K1.46Fe0.8Ti7.2O16 (KFTO) was synthesized by a simple hydrothermal method. Magnetic KFTO microrods were well controlled to long rectangular rods with pyramid-shaped tops. A KFTO growth mechanism was proposed on the basis of examining phase and morphology of the samples acquired at different reaction times. The KFTO morphology was confirmed by the calculated surface energies. The UV-vis diffuse reflectance spectra of KFTO microrods showed double absorption with band gaps of 2.01 and 2.16 eV, which was further confirmed by photoluminescence. First-principles studies revealed that the double absorption and magnetic properties originate from the d-d transitions of Fe3+ under the crystal field. The magnetic property could be applied in ferromagnetic semiconductor devices and the double absorption could be applied in visible-light harvesting. This work highlights the multifunctional KFTO microrods with low cost and environmental friendliness.
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The noble metals Au, Ag and Pt were loaded onto Na0.9Mg0.45Ti3.55O8 (NMTO) using a chemical bath deposition method devised in our recent work for the first time. The composite photocatalysts exhibit more effective photodegradation of methylene blue, due to the Schottky barrier built between NMTO and noble metal. Hot electrons generated during localized surface plasmon processes in metal nanoparticles transfer to the semiconductor, manifesting as a depression of surface potential directly detectable by scanning Kelvin probe microscopy. The key factor responsible for the improved ability of semiconductor-based photocatalysts is charge separation. The most effective weight concentrations of Au, Ag and Pt loaded onto NMTO were found to be 5.00%, 12.6% and 5.55% respectively. NMTO loaded with noble metals shows good photostability and recyclability for the degradation of methylene blue. A possible mechanism for the photodegradation of methylene blue over NMTO loaded with noble metals is proposed. This work highlights the potential application of NMTO-based photocatalysts, and provides an effective method to detect localized surface plasmons.
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OBJECTIVE: To investigate the role and possible molecular mechanism of Krüppel-like factor 7 (KLF7) in the TLR4/NF-κB/IL-6 inflammatory signaling pathway activated by free fatty acids (FFA). METHODS: The mRNA and protein expression levels of KLF7 and the factors of TLR4/NF-κB/IL-6 inflammatory signal pathways were detected by qRT-PCR and Western blotting after cell culture with different concentrations of palmitic acid (PA). The expression of KLF7 or TLR4 in adipocytes was upregulated or downregulated; after that, the mRNA and protein expression levels of these key factors were detected. KLF7 expression was downregulated while PA stimulated adipocytes, and then the mRNA and protein expressions of KLF7/p65 and downstream inflammatory cytokine IL-6 were detected. The luciferase reporter assay was used to determine whether KLF7 had a transcriptional activation effect on IL-6. RESULTS: (1) High concentration of PA can promote the expression of TLR4, KLF7, and IL-6 in adipocytes. (2) TLR4 positively regulates KLF7 expression in adipocytes. (3) KLF7 positively regulates IL-6 expression in adipocytes. (4) PA promotes IL-6 expression via KLF7 in adipocytes. (5) KLF7 has a transcriptional activation on IL-6. CONCLUSION: PA promotes the expression of the inflammatory cytokine IL-6 by activating the TLR4/KLF7/NF-κB inflammatory signaling pathway. In addition, KLF7 may directly bind to the IL-6 promoter region and thus activate IL-6.
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Adipócitos/metabolismo , Interleucina-6/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo , Células 3T3-L1 , Animais , Interleucina-6/genética , Fatores de Transcrição Kruppel-Like/genética , Camundongos , NF-kappa B/genética , RNA Interferente Pequeno/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Receptor 4 Toll-Like/genéticaRESUMO
A facile one-step hydrothermal process was developed for fabrication of three-dimensional hierarchical NiTe2@MoS2 heterostructures. A few layers of MoS2 uniformly grew on the NiTe2 nanorods, possessing a higher surface area. The strategy was extended to CoTe2@MoS2 heterostructures with a few layers of MoS2. The photocatalytic activities of the heterostructures were evaluated by the photodegradation of methylene blue. The composites show strong adsorption ability and much better photocatalytic efficiency in comparison with pure MoS2 microflowers and NiTe2 nanorods. Especially, the NiTe2@MoS2 heterostructure with 40 wt% of MoS2 presents the highest performance in photocatalytic degradation of dye molecules, which is attributed to the formation of hierarchical network between NiTe2 nanorods and MoS2 nanosheets. And the possible mechanism of the enhanced photocatalytic activities was discussed.
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CoTe and CoTe2 nanorods with average diameter of 100 nm were synthesized by a simple hydrothermal process, and different CoTe2 nanostructures were obtained by changing the NaOH concentration. CoTe nanorods exhibit weak ferromagnetism while CoTe2 nanorods present paramagnetic behavior. Different magnetic behaviors occur in the other CoTe2 nanostructures due to Na+ entrance into CoTe2 crystals. A first-principles study on Na-doped CoTe2 confirms the magnetic characteristics.
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We report the tuning of the internal Mn photoluminescence (PL) transition of magnetically-ordered Sr-doped lanthanum manganite (LSMO)/Mn-doped zinc sulfide (ZnS:Mn) nanocomposites (NCs) by applying a static magnetic field in the range of 0-1 T below the critical temperature of â¼225 K. To do that, we have systematically fabricated LSMO/ZnS:Mn at different concentrations (1:1, 1:3, 1:5 and 1:10 wt%) via a straightforward solid-state reaction. X-ray diffraction and Raman analyses reveal that both phases coexist with a high degree of crystallinity and purity. Electron microscopy indicates that the NCs are almost spherical with an average crystal size of â¼6 nm, and that their surfaces are clean and smooth. The bifunctional character of LSMO/ZnS:Mn was evidenced by vibrating sample magnetometry and PL spectroscopy analyses, which show a marked ferromagnetic behavior and a broad, intense Mn orange emission band at room temperature. Moreover, the LSMO/ZnS:Mn at 1:3 wt% exhibits magneto-luminescent (ML) coupling below 225 K, and reaches the largest suppression of Mn-band PL intensity (up to â¼10%) at 150 K, when a magnetic field of 1.0 T is applied. The ML effect persists at magnetic fields as low as 0.2 T at 8 K, which can be explained by evoking a magnetic-ordering-induced spin-dependent restriction of the energy transfer to Mn states. No ML effect was observed in bare ZnS:Mn nanoparticles under the same experimental parameters. Our findings suggest that this NC can be considered as a new ML compound, similar to FeCo/InGaN-GaN and LSMO/ZnO NCs, useful as q-bits for quantum computation. The results presented here bring forth new avenues to better understand the interaction between semiconductors and perovskites, and exploit their synergistic effects in magneto-optics, spintronics and nanoelectronics.