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A chronic disease, hypertension (HTN) is prevalent among the elderly. Exploring the factors that influence HTN and blood pressure (BP) changes is of great public health significance. However, mixed exposure to multiple serum metals has had less research on the effects on BP and HTN for the elderly. From April to August 2019, 2372 people participated in the community physical examination program for the elderly in Tongling City, Anhui Province. We measured BP and serum levels of 10 metals and collected basic demographic information. We analyzed the relationship between metal levels and changes in BP and HTN by the least absolute shrinkage and selection operator regression, Bayesian kernel machine regression model, and generalized linear model. In multiple models, lead (Pb) and cadmium (Cd) were still significantly associated with HTN occurrence after adjusting for potential confounders (Pb: ORquartile 4 VS quartile 1 = 1.20, 95% CI 1.01-1.43; Cd: ORquartile 4 VS quartile 1 = 1.37, 95% CI 1.16-1.62). In the male subgroup, results were similar to those of the general population. In the female group, Cd was positively correlated with HTN and systolic blood pressure, while Pb was not. According to this study, Pb and Cd were correlated with BP and HTN positively, and there was a certain joint effect. To some extent, our findings provide clues for the prevention of hypertension in the elderly.
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Cadmio , Hipertensión , Humanos , Masculino , Femenino , Anciano , Presión Sanguínea , Cadmio/toxicidad , Teorema de Bayes , Plomo/farmacología , Hipertensión/inducido químicamente , Hipertensión/epidemiologíaRESUMEN
Peroxide dianion (O22-) has strong oxidizing activity and ease of proton abstraction and is extremely unstable. Direct and controllable adsorption and release of O22- has large application implication and is a large challenge so far. Here, we use a unique metal (Ni)-organic (diphenylalanine, DPA) framework (MOF), Ni(DPA)2, as adsorbents for absorption and release of O22-. This MOF structure has room-temperature magnetoelectricity via distortion of the Ni-centered octahedron {NiN2O4} and thus possesses a tunable ferroelectric polarization under applied electric/magnetic fields. Controllable adsorption and release of O22- are realized in such a MOF system via electrochemical redox measurements. Structural/spectroscopic characterization and calculations reveal that a number of NH active sites in the nanopores of MOF can effectively adsorb O22- by hydrogen bonds and then tunable ferroelectric polarization induces controllable release of O22- under applied magnetic fields. This work presents a constructive way for controllable adsorption and release of reactive oxygen species.
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The combined molecular dynamics and coordinate driving (MD/CD) method is updated and generalized in this work to broaden its applications in automatically searching reaction pathways for complicated reactions. In this updated version, MD simulations are performed with the GFN's family of methods to systematically sample conformers for almost any systems with atomic numbers Z ≤ 86. The improved CD procedure is greatly accelerated by applying a pre-screening stage at the semiempirical GFN2-xTB level. An automatic module based on the Marcus theory and its improved version (the Wolynes theory) is designed to include single electron transfer (SET) processes into reaction pathways. The capabilities of this method are demonstrated by exploring the most possible reaction pathways of three experimentally reported reactions: the organophosphine-catalyzed trans phosphinoboration, the Fe(II) complex-mediated C(sp2)-H borylation reaction, and the SET-triggered deaminative radical cross-coupling reaction. Comprehensive reaction networks are obtained for all three reactions with reasonable computational costs. Detailed mechanisms for these reactions can account for the reported experimental facts.
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PURPOSE: The effects of air pollution on human health have long been a hot topic of research. For respiratory diseases, a large number of studies have proved that air pollution is one of the main causes. The purpose of this study was to investigate the risk of hospitalization of children with respiratory system diseases (CRSD) caused by six pollutants (PM2.5, PM10, NO2, SO2, CO, and O3) in Hefei City, and further calculate the disease burden. METHOD: In the first stage, the generalized additive models were combined with the distributed lag non-linear models to evaluate the impact of air pollution on the inpatients for CRSD in Hefei. In the second stage, this study used the cost-of-illness approach to calculate the attributable number of hospitalizations and the extra disease burden. RESULT: Overall, all the six kinds of pollutants had the strongest effects on CRSD inpatients within lag10 days. SO2 and CO caused the highest and lowest harm, respectively, and the RR values were SO2 (lag0-5): 1.1 20 (1.053, 1.191), and CO (lag0-6): 1.002 (1.001, 1.003). During the study period (January 1, 2014 to December 30, 2020), the 7-year cumulative burden of disease was 36.19 million CNY under the WHO air pollution standards. CONCLUSION: In general, we found that six air pollutants were risk factors for CRSD in Hefei City, and create a huge burden of disease.
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Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Ambientales , Enfermedades Respiratorias , Niño , Humanos , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Enfermedades Respiratorias/epidemiología , China , Material Particulado/efectos adversos , Material Particulado/análisisRESUMEN
Reversible regulation of ferroelectric polarization possesses great potentials recently in bionic neural networks. Photoinduced cis-trans isomers have changeable dipole moments, but they cannot be directed to some specific orientation. Here, we construct a host-guest composite structure which consists of a porous ferroelectric metal (Ni)-organic framework [Ni(DPA)2] as host and photoisomer, azobenzene (AZB), as guest molecules. When AZB molecules are embedded in the nanopores of Ni(DPA)2 in the form of a single molecule, polarization strength tunable regulation is realized after ultraviolet irradiation of 365 and 405 nm via cis-trans isomerism transformation of AZB. An intrinsic built-in field originating from the distorted {NiN2O4} octahedra in Ni(DPA)2 directs the dipole moments of AZB to the applied electric field. As a result, the overlapped ferroelectric polarization strength changes with content of cis-AZB after ultraviolet and visible irradiation. Such a connection of ferroelectric Ni(DPA)2 structure with cis-trans isomers provides an important strategy for regulating the ferroelectric polarization strength.
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Estructuras Metalorgánicas , Isomerismo , Luz , Rayos UltravioletaRESUMEN
Volatile organic compounds (VOCs) emitted from municipal solid waste incineration power plant (MSWIPP) plays a significant role in the formation of O3 and PM2.5 and odor pollution. Field test was performed on four MSWIPPs in an area of the North China Plain. Nonmethane hydrocarbons (NMHCs) and 102 VOCs were identified and quantified. Ozone formation potential (OFP), secondary organic aerosol formation potential (SOAFP), and odor activity of the detected VOCs were evaluated. Results showed that the average concentration of NMHCs and VOCs were 1648.6 ± 1290.4 µg/m3 and 635.3 ± 588.8 µg/m3, respectively. Aromatics (62.1%), O-VOCs (16.0%), and halo hydrocarbons (10.0%) were the main VOCs groups in the MSWIPP exhaust gas. VOCs emission factor of MSWIPP was 2.43 × 103 ± 2.27 × 103 ng/g-waste. The OFP and SOAFP of MSWIPP were 960.18 ± 2158.17 µg/m3 and 1.57 ± 3.38 µg/m3, respectively. Acrolein as the dominant VOC species was the major odor contributor with a percentage of odor contribution of 65.9%. Benzene and 1,2,4-trimethylbenzene as the dominant VOC species were the main contributors of O3 formation potentials, in which 1,2,4-trimethylbenzene was also the main contributors of SOA formation potential.
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Ozono , Compuestos Orgánicos Volátiles , Incineración , Residuos Sólidos , Odorantes , Centrales EléctricasRESUMEN
The prevalence of overweight or obesity increased rapidly over the past decades in most countries, including China. However, little evidence exists about the effects of long-term exposure to PM2.5 components on overweight or obesity, particularly in developing countries. We measured different weight stages according to body mass index (BMI), and investigated the effects of exposure to PM2.5 components (ammonium [[Formula: see text]], sulfate [[Formula: see text]], nitrate [[Formula: see text]], black carbon and organic matter) on different BMI levels in middle-aged and elderly people of China. Our study explored the effects of single and multiple air pollution exposures on overweight and obesity by using the Generalized Linear Model and Quantile g-Computation model (QgC). This study found a significantly positive association between five PM2.5 components and overweight/obesity. In the QgC model, there was still a positive association between multiple exposure to PM2.5 components and overweight when all PM2.5 components were considered as a whole. In addition, males, the elderly, and urban residents were also more sensitive to five PM2.5 components.
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Contaminantes Atmosféricos , Contaminación del Aire , Humanos , Masculino , Anciano , Persona de Mediana Edad , Sobrepeso/epidemiología , Sobrepeso/etiología , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis , Material Particulado/toxicidad , Material Particulado/análisis , Estudios de Cohortes , Ciudades , Obesidad/epidemiología , Obesidad/etiología , Contaminación del Aire/análisis , China/epidemiología , Exposición a Riesgos AmbientalesRESUMEN
Boron Lewis acid-catalyzed and catalyst-free hydroboration reactions of imines are attractive due to the mild reaction conditions. In this work, the mechanistic details of the hydroboration reactions of two different kinds of imines with pinacolborane (HBpin) are investigated by combining density functional theory calculations and some experimental studies. For the hydroboration reaction of N-(α-methylbenzylidene)aniline catalyzed by tris[3,5-bis(trifluoromethyl)phenyl]borane (BArF 3 ), our calculations show that the reaction proceeds through a boron Lewis acid-promoted hydride transfer mechanism rather than the classical Lewis acid activation mechanism. For the catalyst- and solvent-free hydroboration reaction of imine, N-benzylideneaniline, our calculations and experimental studies indicate that this reaction is difficult to occur under the reaction conditions reported previously. With a combination of computational and experimental studies, we have established that the commercially available BH3 â SMe2 can serve as an efficient catalyst for the hydroboration reactions of N-benzylideneaniline and similar imines. The hydroboration reactions catalyzed by BH3 â SMe2 are most likely to proceed through a hydroboration/B-H/B-N σ-bond metathesis pathway, which is very different from that of the reaction catalyzed by BArF 3 .
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We synthesized a high-nuclear isopolymolybdate cluster (n-Bu4 N)6 H2 [{Mo24 O48 (OMe)32 }{Mo24 O52 (OMe)28 }2 ] â 25H2 O â 6CH3 CN (1) by using [Mo6 O19 ]2- as the base precursor. Crystallographic characterization shows the cluster is composed of an anionic [{Mo24 O48 (OMe)32 }]8- cage and two charge-neutral [{Mo24 O52 (OMe)28 }] cages. Supported by the electrospray ionization mass spectrometry study, the polyoxoanion structural unit [Mo24 O48 (CH3 O)27 ]3- demonstrates strong stability in acetonitrile solution. Moreover, 1 exhibits good proton conductivity of 1.79×10-3 â S cm-1 at 358â K and 98 % relative humidity.
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The pyridine/bis(pinacolate)diboron combination has been found to be able to initiate the iodoperfluoroalkylation of unactivated alkenes with perfluoroalkyl iodides. Theoretical calculations and control experiments indicate that the atom transfer radical addition mechanism is responsible for the formation of iodoperfluoroalkylation products. This metal-free and photo-free strategy is applicable to a wide range of perfluoroalkyl iodides and unactivated alkenes with good functional group tolerance. Further applications in iodoperfluoroalkylation of organic semiconductor-relevant or bioactive molecules demonstrate the synthetic potential of this method.
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Alquenos , Fluorocarburos , Catálisis , Yoduros , PiridinasRESUMEN
Recently, elevated blood pressure (BP) and hypertension (HTN) have caused a huge burden of health loss. Previous studies used ambient air pollutants as a proxy for individual exposure, limiting the assessment of its multiple exposure to health effects. For the first time, this study constructed individual PM2.5 component (SO42-, NO3-, NH4+, OM, and BC) exposure model DAG (Directed Acyclic Graph), DAG-oriented generalized linear model and random forest model, and explored the effects of single and multiple exposures to PM2.5 components on BP at different stages by the generalized linear model (GLM) and Quantile g-Computation (QgC) model based on a large cohort study in China. We defined BP in four stages according to the 2017 ACC/AHA guidelines. After excluding the lack of key information, the cohort analyses ultimately included 9031 participants. Our results showed that the individual PM2.5 component exposure model had good efficacy. Single or multiple exposure to PM2.5 components had significant positive effects on normal BP to elevated BP and elevated BP to stage 1 HTN. In addition, males, the elderly and urban residents were more sensitive to PM2.5 components. This study provided implications for environmental exposure assessment and control of particulate pollution in the future.
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Contaminantes Atmosféricos , Contaminación del Aire , Hipertensión , Anciano , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Contaminación del Aire/análisis , Presión Sanguínea , China/epidemiología , Ciudades , Estudios de Cohortes , Exposición a Riesgos Ambientales/análisis , Humanos , Hipertensión/inducido químicamente , Hipertensión/epidemiología , Masculino , Persona de Mediana Edad , Material Particulado/análisis , Material Particulado/toxicidadRESUMEN
Hypertension (HTN) was a major preventable cause of cardiovascular disease (CVD), contributing to a huge disease burden. Ambient temperature, air pollution and green space were important influencing factors of HTN, and few studies have assessed the effects and interactions of ambient temperature, air pollution and green space on HTN in rural areas. In this study, we selected 8400 individuals randomly in rural areas of Anhui Province by a multi-stage stratified cluster sampling. A total of 8383 individuals were included in the final analysis. We collected particulate pollutants and meteorological data from the local air quality monitoring stations and National Center for Meteorological Science from January 1 to December 31, 2020, respectively. The normalized differential vegetation index (NDVI) of Anhui Province in 2020 was produced and processed by remote sensing inversion on the basis of medium resolution satellite images. The average annual mean exposure concentrations of air pollution, meteorological factors, and NDVI were calculated for each individual based on the geocoded residential address. HTN was defined according the Chinese Guidelines for Prevention and Treatment of HTN. The effects and interactions of ambient temperature, air pollution and green space on HTN were evaluated by generalized linear model and interaction model, respectively. In this study, the prevalence of HTN was 24.14%. The adjusted odd ratio of HTN for each 1 µg/m3 increasing in PM2.5 and PM10, 1 °C of ambient temperature, and 0.1 of NDVI were:1.276 (1.013, 1.043), 1.012 (1.006, 1.018), 0.862 (0.862, 0.981) and 0.669 (0.611, 0.733), respectively. The results showed that air pollutants were positively correlated with HTN, while ambient temperature and green space were negatively correlated with HTN. Meanwhile, the negative associations of green space on HTN could decrease with the increasing concentrations of air pollution, but increase with the rising of ambient temperature.
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Contaminantes Atmosféricos , Contaminación del Aire , Hipertensión , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , China/epidemiología , Estudios Transversales , Exposición a Riesgos Ambientales/análisis , Humanos , Hipertensión/epidemiología , Parques Recreativos , Material Particulado/análisis , TemperaturaRESUMEN
Aim of this study was to evaluate the association between multiple essential microelements exposure and the aggressive clinicopathologic characteristics of papillary thyroid carcinoma (PTC). The concentrations of 10 essential microelements in urine [cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), selenium (Se), strontium (Sr), zinc (Zn), and iodine (I)] were measured in 608 patients newly diagnosed with PTC, including 154 males and 454 females. Chi square test and Wilcoxon rank sum test were used to compare general characteristics among males and females. Multivariate logistic regression was used to evaluate the associations between essential microelements and PTC clinicopathologic characteristics in single- and multi-microelement models. In this study, we only observed that the frequency of lymph node metastasis in males was higher than in females, and males had higher levels of zinc than females, but males had lower levels of iodine than females. It was found that high levels of Fe were associated with decreased risk of PTC tumor size > 1 cm, capsular invasion, and advanced T stage (T3/4a/4b). High levels of Co and Mo were associated with decreased risk of capsular invasion and lymph node metastasis, respectively. However, high levels of Mn and Sr were associated with increased risk of capsular invasion and multifocality respectively, and both were associated with increased risk of advanced T stage (T3/4a/4b). These findings indicated that certain essential microelements might have potential effects on PTC progression and aggressiveness. Further studies are required to confirm these findings.
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Cáncer Papilar Tiroideo/orina , Neoplasias de la Tiroides/orina , Oligoelementos/orina , Adulto , Femenino , Humanos , Masculino , Análisis Multivariante , Cáncer Papilar Tiroideo/diagnóstico , Neoplasias de la Tiroides/diagnósticoRESUMEN
For amphoteric ß-lactam antibiotics, the acid dissociation constant (pK a) is a fundamental parameter to characterize physicochemical and biochemical properties of antibiotics and to predict persistence and removal of drugs. pK a of piperacillin (PIP) is determined by potentiometric titration with a glass electrode. Electrospray ionization mass spectrometry (ESI-MS) is creatively applied to verify the reasonable pK a value at every dissociation step. Two microscopic pK a values (3.37 ± 0.06 and 8.96 ± 0.10) are identified and attributed to the direct dissociation of the carboxylic acid functional group and one secondary amide group, respectively. Different from other ß-lactam antibiotics, PIP presents a dissociation pattern where direct dissociation is involved instead of protonation dissociation. Moreover, the degradation tendency of PIP in an alkaline solution may alter the dissociation pattern or dismiss the corresponding pK a of the amphoteric ß-lactam antibiotics. This work offers a reliable determination of the acid dissociation constant of PIP and a clear interpretation of the effect of stability of antibiotics on the dissociation process.
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In the world, chronic kidney disease (CKD) has been recognized as one of the critical public health problems, and the prevalence is higher in the elderly people. However, there are few studies on the association between exposure to multiple serum metal levels and CKD. A case-control study, we established, for elderly people in Anhui Province, China, to explore the effects of different metals and analyze the effect of mixed exposure on CKD. In this study, 287 cases of CKD and 287 controls were selected in the elderly health physical examination project in Tongling City, Anhui Province. Questionnaire survey, physical examination, and blood collection were conducted. Graphite furnace atomic absorption spectrometry (GFAAS) and inductively coupled plasma optical emission spectrometry (ICP-OES) were used to measure the concentration of serum metals. After selecting by least absolute shrinkage and selection operator (LASSO), 5 metals were brought into the multi-metal model. After adjusting all potential covariates additionally, the concentrations of lead (Pb), cadmium (Cd), cobalt (Co), and manganese (Mn) were significantly associated with CKD risk, whereas Pb, Se, and Cd had significant non-linearity with CKD. Besides, patients with highest quartiles of cobalt (Co), lead (Pb), and manganese (Mn) were 1.64, 1.39, and 0.64 times more possible to have CKD, respectively, as compared with the lowest levels. In the Bayesian kernel machine regression (BKMR) model, cadmium (Cd) had a combined effect with lead (Pb) possibly. This study suggested that the CKD risk was associated with exposure of multiple metals in elderly people. The underlying mechanisms of serum metals and CKD need more experimental and prospective studies to elucidate.
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Metales Pesados , Insuficiencia Renal Crónica , Humanos , Anciano , Metales Pesados/química , Cadmio , Manganeso , Estudios Prospectivos , Teorema de Bayes , Estudios de Casos y Controles , Plomo , Cobalto , Insuficiencia Renal Crónica/inducido químicamente , Insuficiencia Renal Crónica/epidemiologíaRESUMEN
BACKGROUND: Macrosomia has increased rapidly worldwide in the past few decades, with a huge impact on health. However, the effect of PM2.5 and extreme high-temperature (EHT) on macrosomia has been ignored. OBJECTIVE: This study aimed to explore the association between maternal exposure to EHT, PM2.5 and macrosomia based on the Seventh Demographic and Health Survey (DHS) in 14 countries of Africa. METHODS: The study included detailed demographic information on 106 382 births and maternal. Satellite inversion models estimated monthly mean PM2.5 and mean surface temperature of 2 m (SMT2m ). Macrosomia was defined as the birth weight ≥ 4000 g. We used a Cox proportional risk regression model to estimate the association between PM2.5 , EHT and macrosomia. We further explored the susceptibility of exposure to EHT and PM2.5 at different pregnancy periods to macrosomia, and plotted the expose-response curve between PM2.5 and macrosomia risk using a restricted cubic spline function. In addition, the Interplot model was used to investigate the interaction between EHT and PM2.5 on macrosomia. Finally, some potential confounding factors were analysed by stratification. RESULTS: There was the positive association between EHT, PM2.5 and macrosomia, and the risk of macrosomia with the increase in concentrations of PM2.5 without clear threshold. Meanwhile, EHT and PM2.5 had a higher effect on macrosomia in middle/later and early/middle stages of pregnancy, respectively. There was a significant interaction between EHT and PM2.5 on macrosomia. CONCLUSIONS: Maternal exposure to EHT, PM2.5 during pregnancy was associated with an increased risk of macrosomia in Africa.
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Contaminantes Atmosféricos , Contaminación del Aire , Embarazo , Femenino , Humanos , Exposición Materna/efectos adversos , Contaminantes Atmosféricos/efectos adversos , Macrosomía Fetal/inducido químicamente , Material Particulado/efectos adversos , Temperatura , Contaminación del Aire/efectos adversos , ÁfricaRESUMEN
Automobile repair is regarded as a typical domestic source of VOCs in China characterized by numerous sites, wide dispersion and intermittent VOCs emissions. It is of great importance to study and control VOCs from such activities. In this research, emission characteristics, risk assessment and scale effective control of VOCs from automobile repair in Beijing were studied. Results showed that coating spraying and baking were the main processes of VOCs and the major species determined were mostly oxygen-containing VOCs and aromatic hydrocarbons in the case of solvent-based coating usage. Meanwhile, alkanes were determined and accounted for 40 % of total VOCs emissions during the water-based coating spraying and baking. Generally, the total determined VOCs during the automobile repair processes were 1.06-1.27 mg/m3 and 2.93-53.46 mg/m3 for the usage of water-based and solvent-based paint, respectively. Health risk assessments indicated that the residents in the region about 30 m high within a radius of 20 m around the automobile repair plants might suffer from both serious non-carcinogenic and carcinogenic risk threats in the case of solvent-based coating usage in that the values of total hazard index (HI) represented by dichloropropane and acrolein were higher than 1 and the value of lifetime cancer risk (LCR) represented by dichloroethane was higher than 10-5. Besides, those in the region about 30 m high and within a wider radius of 340 m might suffer from carcinogenic risk threat with a certain probability (LCR > 10-6) no matter either solvent-based or water-based coatings were used. As for the scale control of VOCs from automobile repair, independent adsorption by activated carbon combined with mobile regeneration by catalytic combustion was also proposed as an efficient way.
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Contaminantes Atmosféricos , Neoplasias , Ozono , Compuestos Orgánicos Volátiles , Humanos , Beijing , Contaminantes Atmosféricos/análisis , Automóviles , Compuestos Orgánicos Volátiles/análisis , China , Solventes , Carcinógenos , Medición de Riesgo , Agua , Carcinogénesis , Monitoreo del Ambiente , Ozono/análisisRESUMEN
It's well-known that multiple metal elements can lead to the change of oxidative stress response levels in vivo. However, their relationship with age-related cataract (ARC) had not been well studied. We designed a case-control study including 210 individuals with ARC and 210 matched control group. The metal levels in their urine specimens were measured using graphite furnace atomic absorption spectrometry (GFAAS) and inductively coupled plasma optical emission spectrometry (ICP-OES). Least Absolute Shrinkage and Selection Operator (LASSO) regression was used to select representative metals into the multi-element model and reduce dimension. Multivariate logic analysis and Bayesian kernel machine regression (BKMR) were subsequently used to explore the association of ARC risk with multiple metal elements. We found that magnesium (Mg), chromium (Cr), arsenic (As), manganese (Mn), and selenium (Se) were positively associated with ARC in the single-element model. The multiple exposure model indicated a positive association between Mg and As, in which the OR in their highest quartile were 3.32 (95% CI: 1.24-8.89) and 7.09 (95% CI: 2.56-19.63). The BKMR model also showed the effect of As increased monotonically with its increasing concentration, and high levels of Mg and As had a significant positive effect on ARC risk. In conclusion, we found that exposure to multiple metals was associated with increased ARC risk. Further research is needed to verify these findings in the future.
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Arsénico , Selenio , Humanos , Estudios de Casos y Controles , Teorema de Bayes , Metales , China/epidemiologíaRESUMEN
The effect of tBuOK on the existing state of benzylic boronates in the solution phase has been investigated in detail by NMR analysis and DFT calculations. It was determined that simply using an excess of tBuOK (2.0 equivalents) can result in the full deborylation of benzylic boronates to afford free benzyl potassium species. These mechanistic insights were leveraged for the facile construction of ß-silyl/boryl functionalized 1,1-diarylalkanes from aromatic alkenes via the combination of base-mediated silylboration or diborylation of aromatic alkenes and nucleophilic-type reactions with various electrophiles. Based on further machine-learning-assisted screening, the scope of electrophiles for this transformation can be generalized to the challenging aromatic heterocycles. Late-stage functionalization performed on several drug-relevant molecules generates the highly valuable 1,1-diaryl framework.
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Through multiple different pathways, the environmental multiple metals make their ways to the human bodies, where they induce different levels of the oxidative stress response. This study further investigated the impact of multiple-metal exposure on the risk of developing proliferative diabetic retinopathy (PDR). We designed a case-control study with type 2 diabetic patients (T2D), in which the case group was the proliferative diabetic retinopathy group (PDR group), while the control group was the non-diabetic retinopathy group (NDR group). Graphite furnace atomic absorption spectrometry (GFAAS) and inductively coupled plasma optical emission spectrometry (ICP-OES) were used to detect the metal levels in our participants' urine samples. The least absolute shrinkage and selection operator (LASSO) regression approach was used to include these representative trace elements in a multiple exposure model. Following that, logistic regression models and Bayesian kernel machine regression (BKMR) models were used to describe the effect of different elements and also analyze their combined effect. In the single-element model, we discovered that lithium (Li), cadmium (Cd), and strontium (Sr) were all positively related to PDR. The multiple-exposure model revealed a positive relationship between Li and PDR risk, with a maximum quartile OR of 2.80 (95% CI: 1.10-7.16). The BKMR model also revealed that selenium (Se) might act as a protective agent, whereas magnesium (Mg), Li, and Cd may raise the risk of PDR. In conclusion, our study not only revealed an association between exposure to multiple metals and PDR risk but it also implied that urine samples might be a useful tool to assess PDR risk.