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1.
Anal Bioanal Chem ; 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34312691

RESUMO

The increasingly serious environmental pollution worldwide has posed a great threat to the ecosystem and human health, and yet the development of portable in situ monitoring techniques that are sensitive to gaseous and water pollutants remains incomplete. Herein, we report a highly active surface-enhanced Raman spectroscopy (SERS) substrate fabricated by immobilizing gold nanoparticles (AuNPs) onto a polyvinylidene fluoride (PVDF) membrane for continuous in situ SERS detection of pollutants in water and atmosphere. 4-Mercaptobenzoic acid (4-MBA) was adopted as a probe molecule to evaluate the performance of the substrate, and the results indicate that the polymer-based flexible substrate features high sensitivity, uniformity, and repeatability. The fabricated PVDF/SERS substrate was integrated with a portable Raman spectrometer operating under both passing-by and passing-through modes. The integrated system accomplishes quantitative detection and real-time online monitoring of pH in a liquid environment with a response speed of less than 10 s and the rapid SERS response to gas molecules at a low concentration within 30 s. We also demonstrated the highly sensitive detection for mainstream smoke (MS) and sidestream (SS) of cigarette smoke and verified their differences in the main constituent which contributes to the harmful secondhand smoke in public. The developed portable Raman system has excellent application prospects in online liquid and gas environmental detection.

2.
Int J Hyg Environ Health ; 236: 113805, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34271373

RESUMO

BACKGROUND: Although ambient fine particulate matter (PM2.5) has been associated with adverse respiratory outcomes in children, few studies have examined PM2.5 constituents with respiratory diseases in children in China. OBJECTIVES: To investigate the associations of short-term exposure to PM2.5 and its constituents with pediatric emergency room visits (ERVs) for respiratory diseases in Shanghai, China. METHODS: We collected daily concentrations of PM2.5 and its constituents in urban Shanghai from January 1, 2016, to December 31, 2018. Daily pediatric ERVs for four major respiratory diseases, including upper respiratory tract infection, bronchitis, pneumonia, and asthma, were obtained from 66 hospitals in Shanghai during the same period. Associations of exposure to daily PM2.5 and constituents with respiratory ERVs were estimated using the over-dispersed generalized additive models. RESULT: Short-term exposure to PM2.5 and its constituents were associated with increased pediatric ERVs for respiratory diseases. Specifically, an interquartile range increase in the 3-day average PM2.5 level (31 µg/m3) was associated with 1.86% (95%CI: 0.52, 3.22), 1.53% (95%CI: 0.01, 3.08), 1.90% (95%CI: 0.30, 3.52), and 2.67% (95%CI: 0.70, 4.68) increase of upper respiratory tract infection, bronchitis, pneumonia, and asthma ERVs, respectively. As for PM2.5 constituents, we found organic carbon, ammonium, nitrate, selenium, and zinc were associated with higher risk of respiratory ERVs in the single constituent and the constituent-PM2.5 models. CONCLUSION: Short-term exposure to PM2.5 was associated with increased pediatric ERVs for respiratory diseases. Constituents related to anthropogenic combustion and traffic might be the dominant contributors of the observed associations.

3.
Sci Rep ; 11(1): 14233, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244586

RESUMO

The myodural bridge (MDB) is a dense connective tissue bridge connecting the suboccipital muscles to the spinal dura mater, and it has been proven to be a normal common existing structure in humans and mammals. Some scholars believe that the suboccipital muscles can serve as a dynamic cerebrospinal fluid (CSF) pump via the MDB, and they found head rotations promote the CSF flow in human body, which provided evidence for this hypothesis. Head movement is a complex motion, but the effects of other forms of head movement on CSF circulation are less known. The present study explored the effects of head-nodding on CSF circulation. The CSF flow of 60 healthy volunteers was analyzed via cine phase-contrast magnetic resonance imaging at the level of the occipitocervical junction before and after one-minute-head-nodding period. Furthermore, the CSF pressures of 100 volunteers were measured via lumbar puncture before and after 5 times head-nodding during their anesthetizing for surgical preparation. As a result, it was found that the maximum and average CSF flow rates at the level of the upper border of atlas during ventricular diastole were significantly decreased from 1.965 ± 0.531 to 1.839 ± 0.460 ml/s and from 0.702 ± 0.253 to 0.606 ± 0.228 ml/s respectively. In the meantime, the changes in the ratio of cranial and caudal orientation of the net flow volume were found differed significantly after the one-minute-head-nodding period (p = 0.017). And on the other hand, the CSF pressures at the L3-L4 level were markedly increased 116.03 ± 26.13 to 124.64 ± 26.18 mmH2O. In conclusion, the head-nodding has obvious effects on CSF circulation and head movement is one of the important drivers of cerebrospinal fluid circulation. We propose that the suboccipital muscles, participating in various head movements, might pull the dura sac via the myodural bridge, and thus, head movement provides power for the CSF circulation.

4.
Biochem Biophys Res Commun ; 568: 151-157, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34217013

RESUMO

Osteocytes are extremely sensitive to mechanical loading and govern bone remodeling process. Advanced glycation end products (AGEs) have the capacity to induce osteocyte apoptosis. In order to investigate the effects of AGEs on the mechanosensitivity of osteocytes, the osteocytic-like cells (MLO-Y4) were treated with low (50 µg/ml) and high (400 µg/ml) concentrations of AGEs for 1day and exposed to 15 dyne/cm2 of fluid shear stress. Then the F-actin cytoskeleton, prostaglandin E2(PGE2), Nitric oxide (NO), the Wnt/ß-catenin signaling pathway activity mRNA expressions were detected for osteocytes mechanical response changes; osteocalcin (OCN) and receptor activator of nuclear factor-kappa B ligand (RANKL)/osteoprotegerin (OPG) were detected for the regulation on bone remodeling function of osteocytes. The results showed that AGEs accumulation inhibited the sense of osteocytes to external mechincal loading, promoted shear-induced NO and PGE2 release, suppressed the mechanosensitivity of Wnt/ß-catenin signaling pathway, and furthermore promoted OCN and RANKL/OPG mRNA expressions. These indicated AGEs had an adverse impact on the mechanosensitivity of osteocytes, and led to a negative effect on their regulation of bone remodeling process under mechanical stimulation. This work provides a new perspective to interpret the alteration mechanism of osteocytes mechanosensitivity and provides a novel clue for exploring the mechanism of osteoporosis.

6.
Environ Int ; 156: 106739, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34217038

RESUMO

BACKGROUND: Few studies have investigated the association between exposure to fine particulate matter (PM2.5) and infant mortality in developing countries, especially for the health effects of specific PM2.5 constituents. OBJECTIVE: We aimed to examine the association of long-term exposure to specific PM2.5 constituents with infant mortality in 15 African countries from 2005 to 2015. METHODS: Based on the Demographic and Health Surveys (DHS) dataset, we included birth history records from 15 countries in Africa and conducted a multicountry cross-sectional study to examine the associations between specific PM2.5 constituents and infant mortality. We estimated annual residential exposure using satellite-derived PM2.5 for mass and a chemical transport model (GEOS-Chem) for its six constituents, including organic matter (OM), black carbon (BC), sulfate (SO42-), nitrate (NO3-), ammonium (NH4+), and soil dust (DUST). Multivariable logistic regression analysis was employed by fitting single-constituent models, the constituent-PM2.5 models, and the constituent-residual models. We also conducted stratified analyses by potential effect modifiers and examined the specific associations for each country. RESULTS: We found positive and significant associations between PM2.5 total mass and most of its constituents with infant mortality. In the single-constituent model, for an IQR increase in pollutant concentrations, the odds ratio (OR) of infant mortality was 1.03 (95 %CI; 1.01, 1.06) for PM2.5 total mass, and was 1.04 (95 %CI: 1.02, 1.06), 1.04 (95 %CI: 1.02, 1.05), 1.02 (95 %CI: 1.00, 1.03), 1.04 (1.01, 1.06) for BC, OM, SO42-, and DUST, respectively. The associations of BC, OM, and SO42- remained significant in the other two models. We observed larger estimates in subgroups with older maternal age, living in urban areas, using unclean cooking energy, and with access to piped water. The associations varied among countries, and by different constituents. CONCLUSIONS: The carbonaceous fractions and sulfate play a major important role among PM2.5 constituents on infant mortality. Our findings have certain policy implications for implementing effective measures for targeted reduction in specific sources (fossil fuel combustion and biomass burning) of PM2.5 constituents against the risk of infant mortality.

7.
Opt Lett ; 46(14): 3444-3447, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34264234

RESUMO

We experimentally investigate the tunable Doppler shift in an 80 nm thick indium-tin-oxide (ITO) film at its epsilon-near-zero (ENZ) region. Under strong and pulsed excitation, ITO exhibits a time-varying change in the refractive index. A maximum frequency redshift of 1.8 THz is observed in the reflected light when the pump light has a peak intensity of ∼140GW/cm2 and a pulse duration of ∼580fs, at an incident angle of 40°. The frequency shift increases with the increase in pump intensity and saturates at the intensity of ∼140GW/cm2. When the pump pulse duration increases from ∼580fs to ∼1380fs, the maximum attainable frequency shift decreases from 1.8 THz to 0.7 THz. In addition, the pump energy required to saturate the frequency shift decreases with the increase in pump pulse duration for ∼x<1ps and remains unchanged for ∼x>1ps durations. Tunability exists among the pump pulse energy, duration, and incident angle for the Doppler shift of the ITO-ENZ material, which can be employed to design efficient frequency shifters for telecom applications.

8.
Biomater Sci ; 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34236062

RESUMO

The increasing insight into the molecular and cellular processes within the angiogenic cascade assists in enhancing the survival and integration of engineered bone constructs. Copper-doped bioactive glass (Cu-BG) is now a potential structural component of the novel scaffolds and implants used in orthopedic and dental repairs. However, it is difficult for BG, especially micro-nano particles, to be printed into scaffolds and still retain its biological activity and ability to biodegrade. Additionally, the mechanisms of the copper-stimulating autocrine and paracrine effects of human umbilical vein endothelial cells (hUVECs) during repair and regeneration of bone are not yet clear. Therefore, in this study, we created monodispersed micro-nano spherical Cu-BG particles with varying copper content through a sol-gel process. Through in vitro tests, we found that Cu-BG enhanced angiogenesis by activating the pro-inflammatory environment and the HIF-1α pathway of hUVECs. Furthermore, 2Cu-BG diluted extracts directly promoted the osteogenic differentiation of mouse bone mesenchymal stem cells (BMSCs) in vitro. Then, a new 3D-printed tyramine-modified gelatin/silk fibroin/copper-doped bioactive glass (Gel/SF/Cu-BG) scaffold for rat bone defects was constructed, and the mechanism of the profound angiogenesis effect regulated by copper was explored in vivo. Finally, we found that hydrogel containing 1 wt% 2Cu-BG effectively regulated the spatiotemporal coupling of vascularization and osteogenesis. Therefore, Cu-BG-containing scaffolds have great potential for a wide range of bone defect repairs.

9.
Sci Total Environ ; 797: 149025, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34303968

RESUMO

Sulfur (S) dynamics in soils formed from granite remain poorly understood despite its importance as an essential plant macronutrient and component of soil organic matter. We used stable S isotope ratios to trace the sources and biogeochemical processes of S in four forest soil profiles developed on granite under contrasting climate conditions. The soil S is derived mainly from decomposing litter; no significant geogenic contribution to its content is noted as a result of the low S concentration of the granite (~ 5 µg/g). Colder/drier climate results in high organic S retention at the surface due to weak mineralization of organic S. Although warmer/wetter climate increases the S mineralization and leaching loss, SO42- adsorption is an important S retention process in the subsurface. The vertical distribution of S isotope compositions in the soil profiles across the four sites indicates (i) a downward increase in δ34S values in the upper profiles due to continuous mineralization of organic S with an occasional decrease in δ34S values in the subsurface due to dissimilatory sulfate reduction (DSR), (ii) constantly high δ34S values in the middle profiles due to the low water permeability, and (iii) a downward decrease in δ34S values in the low profiles due to increased contribution of bedrock with depth. Regardless of the variation in soil depth and climate, the total S concentration is proportional to the pedogenic Fe/Al minerals, suggesting the important role of secondary Fe/Al minerals in retaining S in soils. This study provides an integration and synthesis of controls of climatic and edaphic variables on S dynamics in forest soil profiles developed on granite.

10.
Mol Biol Rep ; 48(6): 5363-5369, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34213710

RESUMO

Short tandem repeats (STRs) have been extensively used in forensic genetics. However, according to previous studies, the mutation rates of STRs are relatively high and are affected by many factors. Therefore, it is important to analyze STR mutations and determine the influence of underlying factors on STR mutation rates. Mutation rates of 28 autosomal STRs were determined from 8708 paternity testing cases in the Chinese Han population, and the relationships between STR mutation rates and population, sex, age, allele length and heterozygosity were investigated. A total of 279 mutations were observed at 27 loci in a total of 233,530 meiosis cases, including 273 (97.8%) one-step, 5 (1.8%) two-step and 1 (0.4%) three-step mutations. The overall average mutation rate was 1.19 × 10-3 (95% CI 1.06 × 10-3 - 1.34 × 10-3) ranging from 0 (TPOX) to 2.79 × 10-3 (D13S325). Mutation rate comparisons revealed statistically significant differences at several STRs among populations. Paternal mutations occurred more frequently than maternal mutations, at a ratio of 6.04:1, and the mutation rate tended to increase with paternal age. Moreover, our study revealed a bias towards contraction mutations for long alleles and expansion mutations for short alleles. No obvious bias was observed in the overall mutation direction. In addition, STR loci with higher expected heterozygosity (Hexp) tended to have higher mutation rates. This work revealed the relationships between STR mutation rates and several influencing factors, providing useful data and information for further research on STR mutations in forensic genetics.

11.
Nano Lett ; 21(14): 5907-5913, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34251831

RESUMO

A time-dependent change in the refractive index of a material leads to a change in the frequency of an optical beam passing through that medium. Here, we experimentally demonstrate that this effect-known as adiabatic frequency conversion (AFC)-can be significantly enhanced by a nonlinear epsilon-near-zero-based (ENZ-based) plasmonic metasurface. Specifically, by using a 63-nm-thick metasurface, we demonstrate a large, tunable, and broadband frequency shift of up to ∼11.2 THz with a pump intensity of 4 GW/cm2. Our results represent a decrease of ∼10 times in device thickness and 120 times in pump peak intensity compared with the cases of bare, thicker ENZ materials for the similar amount of frequency shift. Our findings might potentially provide insights for designing efficient time-varying metasurfaces for the manipulation of ultrafast pulses.

12.
Spectrochim Acta A Mol Biomol Spectrosc ; 262: 120149, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34252741

RESUMO

Revealing the relationship between lipid droplets (LDs)polarity and disease is indispensable in clinicopathological diagnosis. So far, muscle injury is often ignored as it is not life-threatening as cardiovascular and cerebrovascular diseases, making the exploration of the internal relationship between muscle injury and LDs polarity a gray area. Herein, a fluorescent probe (CCB) with powerful polar-sensitive as well as precise LDs targeting was designed for visualizing the LDs polarity in the pathology of muscle injury. By means of the probe CCB, the identification of cancer cells and the monitoring of LDs polarity changes in dysfunctional cells were successfully realized. Furthermore, the penetration ability of CCB in tissues of mice was tested to verify the applicability of the probe in organisms. Importantly, by CCB, the relationship between muscle damage and LDs polarity was explored, revealing that muscle damage caused a significant decrease in LDs polarity accompanied by a significant increase in fluorescence. Most importantly, it is the first time to reveal the relationship between muscle damage and LDs polarity. Therefore, the probe CCB will be a powerful monitoring platform for diagnosing related diseases caused by abnormal LDs polarity.


Assuntos
Corantes Fluorescentes , Gotículas Lipídicas , Animais , Camundongos , Microscopia de Fluorescência , Músculos
13.
Cell Res ; 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108666

RESUMO

Emerging evidence suggests that children conceived through assisted reproductive technology (ART) have a higher risk of congenital heart defects (CHDs) even when there is no family history. De novo mutation (DNM) is a well-known cause of sporadic congenital diseases; however, whether ART procedures increase the number of germline DNM (gDNM) has not yet been well studied. Here, we performed whole-genome sequencing of 1137 individuals from 160 families conceived through ART and 205 families conceived spontaneously. Children conceived via ART carried 4.59 more gDNMs than children conceived spontaneously, including 3.32 paternal and 1.26 maternal DNMs, after correcting for parental age at conception, cigarette smoking, alcohol drinking, and exercise behaviors. Paternal DNMs in offspring conceived via ART are characterized by C>T substitutions at CpG sites, which potentially affect protein-coding genes and are significantly associated with the increased risk of CHD. In addition, the accumulation of non-coding functional mutations was independently associated with CHD and 87.9% of the mutations were originated from the father. Among ART offspring, infertility of the father was associated with elevated paternal DNMs; usage of both recombinant and urinary follicle-stimulating hormone and high-dosage human chorionic gonadotropin trigger was associated with an increase of maternal DNMs. In sum, the increased gDNMs in offspring conceived by ART were primarily originated from fathers, indicating that ART itself may not be a major reason for the accumulation of gDNMs. Our findings emphasize the importance of evaluating the germline status of the fathers in families with the use of ART.

14.
Sci Total Environ ; 791: 148084, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34139501

RESUMO

BACKGROUND: Obesity is a well-known risk factor for public health. Recent studies found that greenness exposure may protect against obesity. However, the accumulated evidence on associations of greenness-obesity is inconsistent and most of them are from developed countries. OBJECTIVES: This study aimed to evaluate the associations of greenness exposure with indicators of peripheral and central obesity. METHODS: This cross-sectional study was based on a Chinese national Sub-Clinical Outcomes of Polluted Air (SCOPA) prospective cohort across 15 provinces, and 5849 participants with average age of 64.7 were included. Surrounding greenness was estimated with the Enhanced Vegetation Index (EVI), which was calculated at each participant's residential addresses within a 250 m buffer. Weight, height and waist circumference (WC) were measured, and body mass index (BMI) and the waist-to-height ratio% (WHtR%) were calculated based on those measurements. The relationships between EVI and obese outcomes were explored using multiple linear regression and logistic regression models. RESULTS: Non-linear associations were observed between EVI and obese indicators. Participants living in Quartile 3 benefited more than in Quartile 4 compared to the lowest quartile (Quartile 1) of greenness. For peripheral obesity, participants living in Quartile 3 of EVI250m had 0.86 kg/m2 (ß -0.86, 95% CI: -1.10, -0.61) lower BMI, and 46% (OR 0.54, 95% CI: 0.44-0.66) lower odds of peripheral obesity than in Quartile 1. For central obesity, participants living in Quartile 3 of EVI250m had 1.85 cm (ß -1.85, 95% CI: -2.54, -1.15) lower waist circumference, 1.12% (ß -1.12, 95% CI: -1.56, -0.67) lower waist-to-height ratio% (WHtR%), and 33% (OR 0.67, 95% CI: 0.57-0.78) lower odds of central obesity than in Quartile 1 of EVI250m. CONCLUSIONS: Higher levels of greenness were statistically significant associated with lower obesity risk.

15.
Brain Behav ; 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34105901

RESUMO

Among many of the autoimmune diseases observed in patients with myasthenia gravis (MG), myocarditis is one of the most critical. The goal of this review is to systematically describe and investigate the characteristics of MG complicated with myocarditis. We identified 183 records in PubMed (MEDLINE), Web of Science, and EMBASE from 1948 to September 10, 2020. Studies were included if they presented clinical data on MG complicated with myocarditis. Of the 35 patients from 28 studies in this review, 57.14% (20/35) were males, with a mean age of 59.11 ± 15.87. Dyspnea was the most common cardiac symptom accounting for over 60% in the study. Among the 35 patients, 13 cases of myocarditis occurred concomitantly with MG and the longest interval between MG and myocarditis was 7 years. Forty percent of patients developed myocarditis caused by immune checkpoint inhibitors (ICI). Among the patients with myocarditis, over half of the patients were diagnosed by myocardial biopsy. After active immune regulation and symptomatic treatment, only 15 of 35 patients with MG complicated with myocarditis improved, 18 patients died during hospitalization, one patient died due to tumor progression and 1patient died 5 years later. The prognosis of patients with MG complicated with myocarditis is poor, and myocardial enzymes and other indexes need to be monitored for patients taking ICI drugs. Patients with dyspnea who are still not ideally treated by mechanical ventilation should be vigilant against the occurrence of MG complicated with myocarditis.

16.
Water Res ; 200: 117272, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34098268

RESUMO

Rivers play an important role in global water and carbon cycling, but there are still large uncertainties concerning evaporation and aquatic photosynthesis. Here we combined measurements of water chemistry, isotopic compositions (i.e., δDw, δ18Ow, δ13CDIC and ▵14CDIC) and geographic characteristics (i.e., river width) to elucidate in-stream hydrological and biogeochemical processes across rivers in Hainan Island, China. The results showed that dissolved inorganic carbon (DIC) in river waters was largely of modern origin, with about 95% from contemporary biogenic sources based on an isotopic mass balance of ▵14CDIC. Significant evaporation and aquatic primary production co-occurred in these tropical rivers with large amounts of water and DIC being rapidly turned over in the water column, altering the water cycle and the carbon balance. High rates of evaporation and aquatic primary production were observed in the headwater segments, with narrow river width but broad available reactive surface area at the air-water interface. The asymmetric aquatic photosynthesis at different river segments caused the spatial heterogeneities of dissolved solutes. The results suggest that the available reactive area at the water-air interface is responsible for synchronous water loss and dissolved carbon evolution in flat tropical rivers. This study provides evidence that intense evaporation and aquatic photosynthesis mainly occurred in headwater segments, which has implications for understanding global carbon cycling.


Assuntos
Ciclo do Carbono , Rios , Carbono/análise , Isótopos de Carbono/análise , China , Monitoramento Ambiental
17.
Phys Rev Lett ; 126(23): 234503, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34170170

RESUMO

While the drop impact dynamics on stationary surfaces has been widely studied, the way a drop impacts a moving solid is by far less known. Here, we report the physical mechanisms of water drops impacting on superhydrophobic surfaces with horizontal motions. We find that a viscous force is created due to the entrainment of a thin air layer between the liquid and solid interfaces, which competes with the capillary and inertia forces, leading to an asymmetric elongation of the drop and an unexpected contact time reduction. Our experimental and theoretical results uncover consolidated scaling relations: the maximum spreading diameter is controlled by both the Weber and capillary numbers D_{max}/D_{0}∼We^{1/4}Ca^{1/6}, while the dimensionless contact time depends on the capillary number τ/τ_{0}∼Ca^{-1/6}. These findings strengthen our fundamental understandings of interactions between drops and moving solids and open up new opportunities for controlling the preferred water repellency through largely unexplored active approaches.

18.
Chemosphere ; 283: 131191, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34182636

RESUMO

The two shortcomings of the Fenton-like catalyst delafossite-type oxide (CuFeO2) lie in its spontaneous agglomeration and deactivation under neutral working pH. To remedy these drawbacks, novel Fenton-like catalyst chitosan-derived maillard reaction productions coated CuFeO2 with abundant oxygen vacancies (OV-CuFeO2@MRPs) was synthesized by hydrothermal method with no extra chemical reducing agent. The systemic characterization illustrated that richer oxygen vacancies and higher particles dispersion of OV-CuFeO2@MRPs contributed to better Rhodamine B (RhB) degradation under neutral pH compared to pure CuFeO2. Cooper antisite defects in OV-CuFeO2@MRPs were evidenced by X-ray powder diffraction (XRD), fourier transform infrared spectrometer (FTIR), Raman spectra and energy dispersive X-ray spectrometer (EDX) linescan. To keep the charge balance, OV-CuFeO2@MRPs should form rich oxygen vacancies, which was confirmed by X-ray photoelectron spectroscopy (XPS) and solid-state electron paramagnetic resonance spectrometer (solid-state EPR). Furthermore, the electrochemical impedance spectroscopy (EIS) analysis revealed that oxygen vacancies could improve the electron transfer. Scavenging experiments and electron spin resonance spectroscopy (ESR) analysis demonstrated that OH was main active radical during Fenton-like reaction, and the density functional theory (DFT) calculation verified that the oxygen vacancy could effectively adsorb H2O2 and elongate O-O bond of H2O2, thus promoting the activation of H2O2 into OH.

19.
Sex Transm Dis ; 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34192724

RESUMO

BACKGROUND: The prevalence of syphilis is very high in human immunodeficiency virus (HIV)-positive men who have sex with men (MSM), and effective interventions are needed to educate HIV-positive individuals about the behavioral and biological risk factors. Therefore, we developed a standard case management process and conducted a randomized controlled study to investigate the impact on risky sexual behaviors and syphilis in HIV-positive MSM. METHODS: MSM (n = 220) were enrolled and randomized to the case management intervention group and the control group between May 2016 and January 2017. The control group received routine HIV related care. In addition to routine HIV related care, those in the intervention group regularly received extended services from a well-trained case manager. Epidemiological information was collected during the baseline face-to-face interviews by a trained investigator. Serological tests for syphilis and assessments of risky sexual behaviors were performed at baseline and 6 and 12 months after the initiation of treatment. RESULTS: The syphilis incidence rates in the intervention and control groups were 11.3 per 100 person-years and 20.6 per 100 person-years respectively. The multivariable-adjusted hazard ratio (95% CI) for syphilis in case management group was 0.34 (0.14-0.87). The percentages of participants who resumed risky sexual behaviors in both groups were significantly reduced (p < 0.05), but did not significantly differ between two groups. CONCLUSIONS: A case management intervention reduced the incidence of syphilis in HIV-positive MSM. We should further increase the content of case management on the basis of providing routine HIV related care to those people.

20.
Environ Pollut ; 287: 117629, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34182393

RESUMO

Preterm birth (PTB), defined as live birth before the 37th week of gestation, is believed to have profound impacts on the infant's health in later life. Air pollution has been suggested to be a potential risk factor of PTB, but the evidence was inconsistent. In this multicenter birth cohort study, we aimed to examine the association between fine particulate matter (PM2.5) exposure during pregnancy and PTB in China. A total of 5976 live births were identified between Jan. 2009 and Feb. 2011 from 8 provinces in China. Residential exposures to PM2.5 were assigned based on satellite remote sensing estimates. Cox proportional hazards regressions were employed to explore the correlation for each trimester as well as the entire pregnancy. A total of 443 (7.4%) preterm births were observed. The average PM2.5 during pregnancy was 57.2 ± 8.8 µg/m3. We found exposure to PM2.5 during the whole pregnancy (hazard ratio, HR = 1.262; 95% CI: 1.087-1.465) and in the first trimester (HR = 1.114; 95% CI: 1.007-1.232) was associated with higher risk of PTB. The associations of PM2.5 were stronger for subjects with older maternal or paternal age, lower maternal pre-pregnancy BMI, and lower family income. This study adds supports to the cumulating evidence linking PM2.5 exposure and elevated PTB risk. Measures of air pollution reduction are needed during pregnancy, especially at early stage of pregnancy to prevent adverse birth outcomes.

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