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Controlling product selectivity in successive reactions of the same type is challenging owing to the comparable thermodynamic and kinetic properties of the reactions involved. Here, the synergistic interaction of the two phosphoryl groups in bisphosphine dioxides (BPDOs) with a bromo-phosphonium cation was studied experimentally to provide a practical tool for substrate-catalyst recognition. As the eventual result, we have developed a phosphonium-catalyzed monoreduction of chiral BPDOs to access an array of synthetically useful bisphosphine monoxides (BPMOs) with axial, spiro, and planar chirality, which are otherwise challenging to synthesize before. The reaction features excellent selectivity and impressive reactivity. It proceeds under mild conditions, avoiding the use of superstoichiometric amounts of additives and metal catalysts to simplify the synthetic procedure. The accessibility and scalability of the reaction allowed for the rapid construction of a ligand library for optimization of asymmetric Heck-type cyclization, laying the foundation for a broad range of applications of chiral BPMOs in catalysis.
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A comprehensive analysis of spatial transcriptomics was carried out to better understand the progress of halo nevus. We found that halo nevus was characterized by overactive immune responses, triggered by chemokines and dendritic cells (DCs), T cells, and macrophages. Consequently, we observed abnormal cell death, such as apoptosis and disulfidptosis in halo nevus, some were closely related to immunity. Interestingly, we identified aberrant metabolites such as uridine diphosphate glucose (UDP-G) within the halo nevus. UDP-G, accompanied by the infiltration of DCs and T cells, exhibited correlations with certain forms of cell death. Subsequent experiments confirmed that UDP-G was increased in vitiligo serum and could activate DCs. We also confirmed that oxidative response is an inducer of UDP-G. In summary, the immune response in halo nevus, including DC activation, was accompanied by abnormal cell death and metabolites. Especially, melanocyte-derived UDP-G may play a crucial role in DC activation.
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Células Dendríticas , Melanócitos , Nevo com Halo , Humanos , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Melanócitos/metabolismo , Melanócitos/imunologia , Nevo com Halo/metabolismo , Nevo com Halo/imunologia , Uridina Difosfato Glucose/metabolismo , Vitiligo/imunologia , Vitiligo/metabolismo , Masculino , Feminino , Adulto , Apoptose , Linfócitos T/imunologia , Linfócitos T/metabolismo , Adulto Jovem , AdolescenteRESUMO
Cell-cell communication is crucial for regulating signaling and cellular function. However, the precise cellular and molecular changes remain poorly understood in skin aging. Based on single-cell and bulk RNA data, we explored the role of cell-cell ligand-receptor interaction in skin aging. We found that the macrophage migration inhibitory factor (MIF)/CD74 ligand-receptor complex was significantly upregulatedin aged skin, showing the predominant paracrine effect of keratinocytes on fibroblasts. Enrichment analysis and in vitro experiment revealed a close association of the activation of the MIF/CD74 with inflammatory pathways and immune response. Mechanistically, MIF/CD74 could significantly inhibit PPARγ protein, which thus significantly increased the degree of fibroblast senescence, and significantly up-regulated the expression of senescence-associated secretory phenotype (SASP) factors and FOS gene. Therefore, our study reveals that MIF/CD74 inhibits the activation of the PPAR signaling pathway, subsequently inducing the production of SASP factors and the upregulation of FOS expression, ultimately accelerating fibroblast senescence.
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Antígenos de Diferenciação de Linfócitos B , Fibroblastos , Antígenos de Histocompatibilidade Classe II , Fatores Inibidores da Migração de Macrófagos , Análise de Célula Única , Envelhecimento da Pele , Fatores Inibidores da Migração de Macrófagos/genética , Fatores Inibidores da Migração de Macrófagos/metabolismo , Antígenos de Diferenciação de Linfócitos B/genética , Antígenos de Diferenciação de Linfócitos B/metabolismo , Humanos , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/metabolismo , Fibroblastos/metabolismo , Envelhecimento da Pele/genética , Envelhecimento da Pele/fisiologia , Análise de Célula Única/métodos , Transdução de Sinais , Senescência Celular/genética , Oxirredutases Intramoleculares/genética , Oxirredutases Intramoleculares/metabolismo , Análise de Sequência de RNA , Queratinócitos/metabolismo , Queratinócitos/imunologia , PPAR gama/metabolismo , PPAR gama/genética , Pessoa de Meia-Idade , Masculino , Feminino , Pele/metabolismo , Pele/imunologia , Células Cultivadas , AdultoRESUMO
Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent progressive liver disease. Currently, there is only one drug for NAFLD treatment, and the options are limited. Phosphodiesterase-4 (PDE-4) inhibitors have potential in treating NAFLD. Therefore, this study aims to investigate the effect of roflumilast on NAFLD. Here, we fed ob/ob mice to induce the NAFLD model by GAN diet. Roflumilast (1 mg/kg) was administered orally once daily. Semaglutide (20 nmol/kg), used as a positive control, was injected subcutaneously once daily. Our findings showed that roflumilast has beneficial effects on NAFLD. Roflumilast prevented body weight gain and improved lipid metabolism in ob/ob-GAN NAFLD mice. In addition, roflumilast decreased hepatic steatosis by down-regulating the expression of hepatic fatty acid synthesis genes (SREBP1c, FASN, and CD36) and improving oxidative stress. Roflumilast not only reduced liver injury by decreasing serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, but also ameliorated hepatic inflammation by reducing the gene expression of proinflammatory cytokines (TNF-α, IL-1ß, and IL-6). Roflumilast lessened liver fibrosis by inhibiting the expression of fibrosis mRNA (TGFß1, α-SMA, COL1a1, and TIMP-1). Collectively, roflumilast could ameliorate NAFLD, especially in reducing hepatic steatosis and fibrosis. Our findings suggested a PDE-4 inhibitor roflumilast could be a potential drug for NAFLD.
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Aminopiridinas , Benzamidas , Ciclopropanos , Cirrose Hepática , Hepatopatia Gordurosa não Alcoólica , Inibidores da Fosfodiesterase 4 , Animais , Ciclopropanos/farmacologia , Ciclopropanos/uso terapêutico , Aminopiridinas/farmacologia , Aminopiridinas/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/etiologia , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Masculino , Camundongos , Inibidores da Fosfodiesterase 4/farmacologia , Inibidores da Fosfodiesterase 4/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/prevenção & controle , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos Endogâmicos C57BL , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos Obesos , Estresse Oxidativo/efeitos dos fármacos , DietaRESUMO
BACKGROUND: The abnormal low-density protein cholesterol (LDL-C) level in the development of atherosclerosis is often comorbid in individuals with type 2 diabetes mellitus(T2DM). This study aimed to investigate the aggravating effect of abnormal LDL-C levels on coronary artery plaques assessed by coronary computed tomography angiography (CCTA) in T2DM. MATERIALS AND METHODS: This study collected 3439 T2DM patients from September 2011 to February 2022. Comparative analysis of differences in coronary plaque characteristics was performed for the patients between the normal LDL-C level group and the abnormal LDL-C level group. Factors with P < 0.1 in the univariable linear regression analyses were included in the multivariable linear stepwise regression. RESULTS: A total of 2820 eligible T2DM patients were included and identified as the normal LDL-C level group (n = 973) and the abnormal LDL-C level group (n = 1847). Compared with the normal LDL-C level group, both on a per-patient basis and per-segment basis, patients with abnormal LDL-C level showed more calcified plaques, partially calcified plaques, low attenuation plaques, positive remodellings, and spotty calcifications. Multivessel obstructive disease (MVD), nonobstructive stenosis (NOS), obstructive stenosis (OS), plaque involvement degree (PID), segment stenosis score (SSS), and segment involvement scores (SIS) were likely higher in the abnormal LDL-C level group than that in the normal LDL-C level group (P < 0.001). In multivariable linear stepwise regression, the abnormal LDL-C level was validated as an independent positive correlation with high-risk coronary plaques and the degree and extent of stenosis caused by plaques (low attenuation plaque: ß = 0.116; positive remodelling: ß = 0.138; spotty calcification: ß = 0.091; NOS: ß = 0.427; OS: ß = 0.659: SIS: ß = 1.114; SSS: ß = 2.987; PID: ß = 2.716, all P value < 0.001). CONCLUSIONS: Abnormal LDL-C levels aggravate atherosclerotic cardiovascular disease (ASCVD) in patients with T2DM. Clinical attention deserves to be caught by the tailored identification of cardiovascular risk categories in T2DM individuals and the achievement of the corresponding LDL-C treatment goal.
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Biomarcadores , LDL-Colesterol , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana , Diabetes Mellitus Tipo 2 , Placa Aterosclerótica , Valor Preditivo dos Testes , Calcificação Vascular , Humanos , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/epidemiologia , Idoso , LDL-Colesterol/sangue , Biomarcadores/sangue , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/epidemiologia , Calcificação Vascular/sangue , Fatores de Risco , Medição de Risco , Dislipidemias/sangue , Dislipidemias/epidemiologia , Dislipidemias/diagnóstico , Estudos Retrospectivos , Vasos Coronários/diagnóstico por imagem , Índice de Gravidade de Doença , Prognóstico , Estudos TransversaisRESUMO
Introduction of the trifluoromethyl (CF3) group into organic compounds has garnered substantial interest because of its significant role in pharmaceuticals and agrochemicals. Here, we report a hydroxylamine-mediated radical process for C(sp2)-H trifluoromethylation of terminal alkenes. The reaction shows good reactivity, impressive E/Z selectivity (up to >20 : 1), and broad functional group compatibility. Expansion of this approach to perfluoroalkylation and late-stage trifluoromethylation of bioactive molecules demonstrates its promising application potential. Mechanistic studies suggest that the reaction follows a radical addition and subsequent elimination pathway.
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Trinitarian designs in the morphology, components, and microstructure remain challenging for advanced electromagnetic wave absorption (EMWA) materials with light weight, strong absorption, and well-defined structure-function relationships. Herein, a series of X-doped MoS2/Cu9S5 with multilevel honeycomb structures (X-MoS2/Cu9S5 MHs, X = P, Si, Ge) were designed by space-confined growth and in situ sulfidation of a polyoxometalate-based metal-organic framework. X-MoS2/Cu9S5 MHs possess low density, high surface area, and abundant cation-cuprum and anion-sulfur double vacancies (VCu and VS) simultaneously that are unmatched by conventional EMWA materials. Also, the systematic investigation of the doping effect of various polyoxometalate heteroatoms on VCu and VS in the microhoneycomb has been conducted. Experimental results and density functional theory calculations reveal that the excellent EMWA performance (-56.21 dB) results from the synergistic effect of morphology design, component optimization, and vacancy regulation. This study not only provides an important opportunity to understand a morphology-component-microstructure strategy in electromagnetic wave absorption but also builds a noteworthy bridge between bioinspired engineering and microscale absorbers.
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A brand-new procedure for the synthesis of 3-alkynylated 3,3-disubstituted isoindolinones has been disclosed via a HOTf or Fe(OTf)3-catalyzed dehydrative alkynylation of 3-hydroxyisoindolinones with terminal alkynes. Aryl, alkenyl and alkyl terminal alkynes are suitable to couple with a broad range of 3-hydroxyisoindolinones to afford the desired products in moderate to good yields. This protocol features the use of an inexpensive catalyst, mild reaction conditions, broad substrate scope and easy elaboration of the products.
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AIM: To examine the impact of both individual and cumulative social determinants of health (SDoH) on the likelihood of developing periodontitis, while also exploring any gender disparities in this relationship. MATERIALS AND METHODS: Data of self-reported SDoH domains and sub-items based on Healthy People 2030 were obtained from the U.S. National Health and Nutrition Examination Surveys between 1999 and 2014. Logistic regression models, weighted by survey responses, were used to examine the relationship between SDoH (including eight sub-items and the cumulative number of unfavourable SDoH) and periodontitis. The results were further analysed by gender. RESULTS: A total of 18,075 participants (8867 males and 9208 females) were included in the main analysis, of which 5814 (32.2%) had periodontitis. The study found that certain unfavourable SDoH were individually associated with higher odds of periodontitis, and the cumulative number of unfavourable SDoH was positively linked to the odds of developing periodontitis. Furthermore, males exposed to more unfavourable SDoH appeared to be more susceptible to developing periodontitis than females. CONCLUSIONS: The findings suggest that unfavourable SDoH, especially when they accumulate, are associated with an increased odds of periodontitis and contribute to gender disparities within the U.S.
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Periodontite , Determinantes Sociais da Saúde , Feminino , Masculino , Humanos , Inquéritos Nutricionais , Estudos Transversais , Modelos Logísticos , Periodontite/epidemiologiaRESUMO
BACKGROUND AND AIMS: Engaging in recommended levels of physical activity (PA) is associated with reduced overall and cause-specific mortality rates. Our study aims to examine the relationship between gardening-specific PA and all-cause and cause-specific mortality based on representative U.S. adults. METHODS AND RESULTS: A total of 13,812 adults representing 663.5 million non-institutionalized U.S. adults were included in the National Health and Nutrition Examination Survey. Self-reported gardening activity (GA) was assessed by a validated questionnaire, and outcomes of interest were all-cause mortality and mortality specific to certain causes. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using survey-multivariable Cox proportional hazards models. During a median follow-up period of 16.8 years (Interquartile range = 14.8-18.7), there were 3,476 deaths. After adjusting for potential covariates, we found that participants exposed to GA were more likely to have a lower risk of total mortality [HR (95% CI): 0.76 (0.68, 0.85), P-value < 0.001], cancer-specific mortality [HR (95% CI): 0.81 (0.67, 0.99), P-value < 0.05], cardiovascular disease mortality [HR (95% CI): 0.65 (0.53, 0.80), P-value < 0.001], and respiratory disease mortality [HR (95% CI): 0.66 (0.45, 0.98), P-value < 0.05], compared to those without GA exposure. Furthermore, engaging in GA more frequently and for longer durations was significantly associated with a lower total mortality risk. CONCLUSION: Our study provides evidence that engaging in GA is associated with a decreased risk of overall and cause-specific mortality. However, further longitudinal or interventional studies are needed to investigate the potential benefits of GA.
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Causas de Morte , Jardinagem , Inquéritos Nutricionais , Fatores de Proteção , Comportamento de Redução do Risco , Humanos , Masculino , Feminino , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Fatores de Risco , Adulto , Fatores de Tempo , Medição de Risco , Idoso , Estilo de Vida SaudávelRESUMO
BACKGROUND: Tsutsugamushi, also known as bush typhus, is a naturally occurring disease caused by Orientia tsutsugamushi. We reported a case of vertical mother-to-newborn transmission of Orientia tsutsugamushi infection in a newborn from Yunnan (China). CASE PRESENTATION: Decreased fetal movements were observed at 39 weeks of gestation. After birth, the newborn (female) had recurrent fever, shortness of breath, and bruising around the mouth and extremities. At 5 h 58 min of age, the newborn was admitted for fever, shortness of breath and generalized rash. The liver was palpable 3 cm below the costal margin, and the limbs showed pitting edema. There was subcutaneous bleeding. Investigations suggested heavy infection, myocardial damage, decreased platelets. Treatment with cefotaxime and ampicillin failed. The mother was hospitalized at 29 weeks of gestation with a fever for 4 consecutive days, and an ulcerated crust was found in the popliteal fossa. Due to this pregnancy history, A diagnosis of Orientia tsutsugamushi infection was suspected in our index case and confirmed by macrogenomic testing and she was treated with vancomycin and meropenem, and later azithromycin for 1 week. The newborn was discharged in good general condition, gradually normalizing body temperature, and decreasing rash and jaundice. There were no abnormalities on subsequent blood macrogenomic tests for the baby. And one month later she showed good mental health, sleep, and food intake and no fever, rash, or jaundice. CONCLUSION: Determining the cause of symptoms is the key to treating diseases, especially the rare diseases that can be misdiagnosed. SUITABLE FOR PEOPLE WITH: Infectious Diseases; Neonatology; Obstetrics.
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Exantema , Doenças do Recém-Nascido , Icterícia , Tifo por Ácaros , Feminino , Humanos , Recém-Nascido , China , Dispneia , Febre/diagnóstico , Tifo por Ácaros/diagnósticoRESUMO
BACKGROUND: Photodynamic therapy (PDT) is an effective treatment for actinic keratosis (AK) and uses different light sources as well as photosensitizers. In addition, PDT is often combined with other physical therapies or drugs. OBJECTIVES: This study was aimed to compare the efficacy of different PDTs against AK lesions based on Complete Response (CR) by conducting a network meta-analysis (NMA). METHODS: Randomized controlled trials (RCTs) using PDT for AK were screened and a Bayesian model was developed to perform an NMA of CR at 3 months after the first treatment. RESULTS: Twenty-six trials involving 2285 patients and 14 treatments were included. The treatments were broadly divided into mono-PDT and combination therapy. The photodynamic monotherapies included methyl 5-aminolevulinic acid (MAL)-daylight (DL)-PDT, MAL-light-emitting diode (LED)-PDT, 5-aminolevulinic acid (ALA)-LED-PDT, etc. Combination therapies included ablative fractional laser (AFL)-assisted MAL-LED-PDT, calcipotriol (CAL)-assisted MAL-LED-PDT, and 5-fluorouracil (5-Fu)-assisted MAL-DL-PDT. The results of the NMA showed that there is a high probability that AFL-MAL-LED-PDT is the most effective treatment option, followed by CAL-MAL-LED-PDT and ALA-LED-PDT. The subgroup analysis showed that MAL-based PDT had better efficacy when using LED versus other light sources, while LED-based PDT was likely to have better efficacy when using ALA versus other photosensitizers. CONCLUSIONS: The results of this NMA suggest that AFL-MAL-LED-PDT may be the superior choice for achieving complete clearance of AK lesions. PDT using LED as the light source and ALA as the photosensitizer may be more effective for the treatment of AK. However, more RCTs are needed to verify the results of this analysis.
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OBJECTIVE: To evaluate the effects of argatroban on the levels of Hcy, hs-CRP and FIB in patients with acute cerebral infarction (ACI). METHODS: A retrospective analysis was performed on 382 patients with ACI who were hospitalized in the Department of Neurology of our hospital from January 2017 to December 2019. Among them, 158 patients received conventional treatment as the control group and 224 patients received combined treatment with argatroban as the study group. NHISS score, mRS score, Hcy, hs-CRP, FIB level, quality of life, adverse reactions were compared between the two groups after treatment. The levels of Hcy and hs-CRP in patients with different mRS scores were compared. RESULTS: A superior clinical efficacy of the study group was observed than the control group (p < 0.05). The study group witnessed a remarkably lower NHISS score, Hcy, hs-CRP and FIB level as compare to the control group (p < 0.05). The ADL and FMA scores in the study group were higher than those in the control group (p < 0.05). The levels of Hcy and hs-CRP in mRS 0-2 patients were lower than those in mRS 3-6 patients (p < 0.05). CONCLUSION: Argatroban in ACI patients can significantly enhance the clinical efficacy and improve the quality of life. It is closely related to the reduction of Hcy and hs-CRP levels, but the mechanism needs to be further studied.
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Biochar preparation and application is an anticipated pathway for the resource utilization of biogas residue. In this study, biochars were prepared by the pyrolysis of biogas residue from food waste anaerobic digestion (named as BRBCs) under various pyrolysis temperatures (300, 500, 700, and 900 °C), and the effect of pyrolysis temperatures on the physicochemical characteristics of BRBCs was examined. The adsorption performance toward ciprofloxacin (CIP), a typical antibiotic in waterbodies, was also investigated. The results showed that pyrolysis temperature significantly changed the physicochemical properties of BRBCs. In addition, the minerals in the biogas residue, especially SiO2, were rearranged to form a mesoporous structure in biochar through a self-template strategy (without activator). BRBC prepared at 900 °C exhibited a high specific surface area and pore volume, well-developed mesopore structure, and more carbon structure defects, and exhibited the largest CIP adsorption capacity with 70.29 mg g-1, which was ascribed to the combined interaction of pore diffusion, π-π interactions, hydrogen bonding, complexation, and electrostatic forces. Furthermore, the adsorption of CIP by BRBC900 was well described by two-compartment kinetic and Langmuir isotherm models. BRBC900 showed good adsorption performance toward CIP at pH 7-9. The adsorption of CIP by BRBC is a spontaneous, exothermic, entropy-increasing process. Moreover, BRBC also presented a good recycling potential. Therefore, the preparation of mesoporous biochar based on a self-template strategy not only provides an option for the resource utilization of biogas residue but also offers a new option for the treatment of antibiotic wastewater.
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Biocombustíveis , Carvão Vegetal , Ciprofloxacina , Pirólise , Ciprofloxacina/química , Carvão Vegetal/química , Biocombustíveis/análise , Adsorção , Poluentes Químicos da Água/química , Temperatura , Porosidade , CinéticaRESUMO
Modification is widely used to enhance the adsorption performance of pristine hydrochar (HBC) and pyrochar (BC). However, comparisons between modified HBC and BC toward pollutant removal have rarely been reported. In this study, pristine HBC and BC derived from rice straw were first produced, and then citric acid (CA) was used as a modifier to synthesize CA-modified HBC (CAHBC) and CA-modified BC (CABC). Furthermore, the adsorption performance of biochars toward methylene blue (MB) was investigated. The results showed that BC exhibits relatively rough surfaces and contains more minerals (ash), whereas HBC has plentiful O-containing functional groups and fewer minerals. CA modification partially removed minerals from the surface of BC, which weakened the ion exchange, surface complexation, and n-π interaction, resulting in a lower adsorption ability toward MB. By contrast, CA produced more O-containing functional groups on the surface of HBC, which strengthened the hydrogen bonding and electrostatic interaction, thus increasing the adsorption capacity toward MB. The two-compartment model showed a good fit to the adsorption process of MB on CAHBC, and the isotherm data for MB adsorption by HBC and CAHBC are suitable for the Freundlich model. The highest adsorption amount of MB using CAHBC was 80.13 mg·g-1, which was 27.66% higher than that for CABC. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analysis indicated that the carboxyl groups in the surface functional groups of CAHBC played a crucial role in the MB adsorption process. In addition, CAHBC showed a good performance for a wide range of pH values (4.0-10.0) and under the interference of coexisting ions, and also presented a recycling ability. Furthermore, the adsorption of MB on CAHBC biochar was a spontaneous, exothermic, degree-of-randomness-increasing process. Consequently, CA modification of HBC is a promising strategy and could be used for MB removal from aquatic environments.
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Carvão Vegetal , Ácido Cítrico , Azul de Metileno , Minerais , Poluentes Químicos da Água , Azul de Metileno/química , Adsorção , Ácido Cítrico/química , Carvão Vegetal/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Minerais/química , Oxigênio/químicaRESUMO
Deoxygenation of phosphine oxides is of great significance to synthesis of phosphorus ligands and relevant catalysts, as well as to the sustainability of phosphorus chemistry. However, the thermodynamic inertness of PâO bonds poses a severe challenge to their reduction. Previous approaches in this regard rely primarily on a type of PâO bond activation with either Lewis/Brønsted acids or stoichiometric halogenating reagents under harsh conditions. Here, we wish to report a novel catalytic strategy for facile and efficient deoxygenation of phosphine oxides via successive isodesmic reactions, whose thermodynamic driving force for breaking the strong PâO bond was compensated by a synchronous formation of another PâO bond. The reaction was enabled by PIII/PâO redox sequences with the cyclic organophosphorus catalyst and terminal reductant PhSiH3. This catalytic reaction avoids the use of the stoichiometric activator as in other cases and features a broad substrate scope, excellent reactivities, and mild reaction conditions. Preliminary thermodynamic and mechanistic investigations disclosed a dual synergistic role of the catalyst.
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Keratinocytes regulate melanogenesis in a paracrine manner. Previous studies have shown that melatonin can directly inhibit melanin production in the melanocytes. However, it is unclear whether melatonin can also indirectly regulate melanogenesis through the keratinocytes. In this study, we explored the role of melatonin in regulating keratinocyte-mediated melanogenesis using reconstructed human epidermis (RHE). Melatonin showed an inhibitory effect on melanin synthesis in this model. Furthermore, the conditioned media from melatonin-treated HaCaT cells downregulated melanogenesis-related genes, including MITF, TYR, TYRP1, DCT and RAB27A in the pigment MNT1 cells, and decreased levels of phosphorylated ERK, JNK and p38. RNA sequencing further showed that mitochondrial functions and oxidative stress pathway in the MNT1 cells were inhibited by the conditioned medium from melatonin-treated HaCaT cells. Furthermore, melatonin reduced the secretion of ET-1 and PTGS2 from HaCaT cells by inhibiting the JAK2/STAT3 signalling pathway. In conclusion, melatonin downregulates the paracrine factors ET-1 and PTGS2 in the keratinocytes by inhibiting the JAK2/STAT3 pathway, which reduces melanin production in pigment cells. Thus, melatonin has a potential therapeutic effect on skin pigmentation disorders.
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Melaninas , Melatonina , Humanos , Melaninas/metabolismo , Melatonina/farmacologia , Melatonina/metabolismo , Ciclo-Oxigenase 2/metabolismo , Queratinócitos/metabolismo , Melanócitos/metabolismo , Monofenol Mono-Oxigenase/metabolismoRESUMO
A Hg(OTf)2-catalyzed tandem phospha-Michael addition/cyclization/dehydration of 2-hydroxychalcones with H-phosphine oxides is presented. This protocol provides a new and supplementary approach for the preparation of 4-phosphorylated 4H-chromenes in good yields (up to 99%). In addition, this domino reaction allows the successful construction of two new C-P and C-O bonds in a one-pot operation.
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BACKGROUND: Air pollution exposures are increasingly suspected to influence the development of childhood adiposity, especially focusing on outdoor exposure, but few studies investigated indoor exposure and childhood obesity. OBJECTIVES: We aimed to examine the association between exposure to multiple indoor air pollutants and childhood obesity in Chinese schoolchildren. METHODS: In 2019, we recruited 6499 children aged 6-12 years from five Chinese elementary schools in Guangzhou, China. We measured age-sex-specific body mass index z score (z-BMI), waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR) on standard procedures. Four different indoor air pollution (IAP) exposures, including cooking oil fumes (COFs), home decoration, secondhand smoke (SHS), and incense burning, were collected by questionnaire and then converted into an IAP exposure index with four categories. Association between indoor air pollutants and childhood overweight/obesity as well as four obese anthropometric indices were assessed by logistic regression models and multivariable linear regression models, respectively. RESULTS: Children exposed to ≥3 types of indoor air pollutants had higher z-BMI (coefficient [ß]:0.142, 95% confidence interval [CI]:0.011-0.274) and higher risk of overweight/obesity (odd ratio [OR]:1.27, 95%CI:1.01-1.60). And a dose-response relationship was discovered between the IAP exposure index and z-BMI as well as overweight/obesity (pfor trend<0.05). We also found that exposure to SHS and COFs was positively associated with z-BMI and overweight/obesity (p < 0.05). Moreover, there was a significant interaction between SHS exposure and COFs on the higher risk of overweight/obesity among schoolchildren. Boys appear more susceptible to multiple indoor air pollutants than girls. CONCLUSIONS: Indoor air pollution exposures were positively associated with higher obese anthropometric indices and increased odds of overweight/obesity in Chinese schoolchildren. More well-designed cohort studies are needed to verify our results.
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Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluição do Ar , Obesidade Infantil , Poluição por Fumaça de Tabaco , Masculino , Feminino , Humanos , Criança , Obesidade Infantil/epidemiologia , Obesidade Infantil/etiologia , Poluição do Ar em Ambientes Fechados/efeitos adversos , Sobrepeso , Estudos Transversais , População do Leste Asiático , Poluentes Atmosféricos/análise , Índice de Massa Corporal , Poluição por Fumaça de Tabaco/efeitos adversosRESUMO
Circulating nitrate is actively absorbed by salivary glands and secreted into the oral cavity, where it is reduced to nitrite by oral nitrate-reducing bacteria. This process has previously been considered harmful because nitrate and nitrite can promote the formation of potentially carcinogenic N-nitrosamines. However, recent studies have shown that nitrate may have other physiological functions, and it can serve as a precursor for the systemic production of nitric oxide (NO) and perform NO-like functions, such as promoting vasodilation, regulating metabolic diseases, alleviating senescence, and protecting the digestive system. Inside the oral cavity, NO is likely to inhibit sensitive species as part of the nonspecific oral immune system. Exogenous administration of nitrate can maintain a balance in the pH of saliva. Oral nitrate-reducing bacteria can control the progression of caries by metabolizing lactic acid and reducing its accumulation, which is beneficial to the homeostasis of the oral microecology. In the current manuscript, we reviewed nitrate-reducing bacteria and their nitrate-metabolizing functions during the development of caries. Furthermore, we listed the effects of probiotics and dietary modification, which may be a promising method to prevent the occurrence of caries. We believe that this review provides novel ideas for the prevention of caries and treatment in clinical settings.