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1.
Ecotoxicol Environ Saf ; 265: 115518, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37776819

RESUMO

Prenatal exposure to heavy metals causes multiple hazards to fetal growth and development. Epidemiological studies on the association between heavy metals and fetal chromosomal abnormalities (CAs) are lacking. We conducted a nested case-control study in a cohort of high-risk pregnant women in China from September 2018 to June 2021. A total of 387 participants were diagnosed with fetal CAs in the case group and 699 were diagnosed with a normal karyotype in the control group. Amniotic fluid concentrations of 10 metals (barium, cobalt, antimony, manganese, ferrum, copper, selenium, strontium, vanadium, and chromium) were measured using inductively coupled plasma-mass spectrometry. We applied quantile g-computation and weighted quantile sum regression to assess the overall effect of metal mixtures and identify metals with significant weight. Logistic and Poisson regression analyses were used to estimate the effects of metals on CAs and CAs subtypes. Our results showed that the metal mixture concentrations were positively associated with the risk of fetal CAs. In adjusted logistic models, Sb was associated with fetal CAs (OR=1.15, 95% CI: 1.02-1.30), and revealed a linear dose-response relationship between Sb level and the risk of fetal CAs. Additionally, the exploratory analysis revealed that Sb levels were associated with Klinefelter syndrome (OR=1.452, 95% CI: 1.063-1.984) and Turner syndrome (OR=1.698; 95% CI,1.048-2.751). Our study revealed that metal mixtures are associated with a higher risk of fetal CAs and that this association may be driven primarily by Sb. Moreover, we provide a genetic perspective on the effects of heavy metals on sexual development in humans.

2.
Ecotoxicol Environ Saf ; 258: 114980, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37148752

RESUMO

Perfluoroalkyl substances (PFASs) are a classic environmental endocrine disruptor with carcinogenic risk. Epidemiological studies have shown that PFASs contamination is associated with breast cancer development, but the mechanism remains largely unknown. This study first obtained complex biological information about PFASs-induced breast cancer through the comparative toxicogenomics database (CTD). The Protein-Protein Interaction (PPI) network, Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analysis were utilized to investigate molecular pathways. The ESR1 and GPER expression levels at different pathological stages and the prognosis of Breast Cancer patients were confirmed using the Cancer Genome Atlas (TCGA) database. Furthermore, we verified this by cellular experiments and the results showed breast cancer cell migration and invasion were promoted by PFOA. Two estrogen receptors (ER), ERα and G protein-coupled estrogen receptor (GPER), mediated the promoting effects of PFOA by activating MAPK/Erk and PI3K/Akt signaling pathways. These pathways were regulated by ERα and GPER in MCF-7 cells or independently by GPER in MDA-MB-231 cells. Overall, our study provides a better overview of the mechanisms associated with PFASs-induced breast cancer development and progression.


Assuntos
Neoplasias da Mama , Fluorocarbonos , Humanos , Feminino , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Neoplasias da Mama/metabolismo , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proliferação de Células , Estrogênios/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Fluorocarbonos/toxicidade , Linhagem Celular Tumoral
3.
Artigo em Inglês | MEDLINE | ID: mdl-36631073

RESUMO

BACKGROUND: Weather conditions are a possible contributing factor to age-related macular degeneration (AMD), a leading cause of irreversible loss of vision. The present study evaluated the joint effects of meteorological factors and fine particulate matter (PM2.5) on AMD. METHODS: Data was extracted from a national cross-sectional survey conducted across 10 provinces in rural China. A total of 36,081 participants aged 40 and older were recruited. AMD was diagnosed clinically by slit-lamp ophthalmoscopy, fundus photography, and spectral domain optical coherence tomography (OCT). Meteorological data were calculated by European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis and were matched to participants' home addresses by latitude and longitude. Participants' individual PM2.5 exposure concentrations were calculated by a satellite-based model at a 1-km resolution level. Multivariable-adjusted logistic regression models paired with interaction analysis were performed to investigate the joint effects of meteorological factors and PM2.5 on AMD. RESULTS: The prevalence of AMD in the study population was 2.6% (95% CI 2.42-2.76%). The average annual PM2.5 level during the study period was 63.1 ± 15.3 µg/m3. A significant positive association was detected between AMD and PM2.5 level, temperature (T), and relative humidity (RH), in both the independent and the combined effect models. For PM2.5, compared with the lowest quartile, the odds ratios (ORs) with 95% confidence intervals (CIs) across increasing quartiles were 0.828 (0.674,1.018), 1.105 (0.799,1.528), and 2.602 (1.516,4.468). Positive associations were observed between AMD and temperature, with ORs (95% CI) of 1.625 (1.059,2.494), 1.619 (1.026,2.553), and 3.276 (1.841,5.830), across increasing quartiles. In the interaction analysis, the estimated relative excess risk due to interaction (RERI) and the attributable proportion (AP) for combined atmospheric pressure and PM2.5 was 0.864 (0.586,1.141) and 1.180 (0.768,1.592), respectively, indicating a synergistic effect between PM2.5 and atmospheric pressure. CONCLUSIONS: This study is among the first to characterize the coordinated effects of meteorological factors and PM2.5 on AMD. The findings warrant further investigation to elucidate the relationship between ambient environment and AMD.


Assuntos
Poluentes Atmosféricos , Degeneração Macular , Humanos , Adulto , Pessoa de Meia-Idade , Estudos Transversais , Poluentes Atmosféricos/análise , Material Particulado/análise , China/epidemiologia , Degeneração Macular/epidemiologia , Degeneração Macular/etiologia , Conceitos Meteorológicos
4.
Int J Syst Evol Microbiol ; 66(3): 1352-1357, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26745974

RESUMO

A novel heterotrophic, aerobic, Gram-stain-negative, rod-shaped and yellow bacterium, designated strain G18T, was isolated from a water sample collected from the deep South China Sea. Strain G18T grew at 4-40 °C (optimum 28-32 °C), at pH 6.0-8.0 (optimum pH 6.5-7.5) and with 0-12 % (w/v) NaCl (optimum 3-4 %). The organism was mesophilic and piezotolerant, its optimal growth pressure was 0.1 MPa, which was lower than that at the depth from which it was isolated. Its optimal growth temperature was higher than that at the depth of its isolation. The predominant cellular fatty acids were C15 : 0iso, C17 : 0iso 3-OH and C15 : 1iso. The major polar lipids were composed of phosphatidylethanolamine, one unknown aminolipid and one unknown polar lipid. The major respiratory quinone was menaquinone 6. The G+C content of the genomic DNA was 35 mol%. Phylogenetic analysis, based on 16S rRNA gene sequences, revealed that strain G18T clustered with species of the genus Leeuwenhoekiella with validly published names within the family Flavobacteriaceae with 95.9-98.2 % sequence similarity. DNA-DNA reassociation values ranged from 9 to 42 %. Differential phenotypic properties, together with the phylogenetic distinctiveness, suggest that strain G18T differs from species of the genus Leeuwenhoekiella with validly published names. On the basis of the polyphasic evidence, strain G18T represents a novel species, isolated from deep-sea, of the genus Leeuwenhoekiella for which the name Leeuwenhoekiella nanhaiensis sp. nov. is proposed. The type strain is G18T ( = CCTCC AB 2015204T = KCTC 42729T).

5.
Int J Syst Evol Microbiol ; 63(Pt 10): 3579-3584, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23584286

RESUMO

A novel ikarugamycin-producing actinomycete, designated strain NEAU-Da3(T), was isolated from soybean root [Glycine max (L.) Merr.] and characterized using a polyphasic approach. 16S rRNA gene sequence similarity studies showed that strain NEAU-Da3(T) belonged to the genus Streptomyces, and was most closely related to Streptomyces carpaticus NRRL B-16359(T) (99.5 %), Streptomyces cheonanensis VC-A46(T) (99.3 %) and Streptomyces xiamenensis MCCC 1A01550(T) (97.2 %); similarities to other type strains of species of the genus Streptomyces were lower than 97.1 %. The maximum-likelihood phylogenetic tree based on 16S rRNA gene sequences showed that the isolate formed a distinct phyletic line with S. carpaticus NRRL B-16359(T), S. cheonanensis VC-A46(T) and S. xiamenensis MCCC 1A01550(T). This branching pattern was also supported by the tree reconstructed with the neighbour-joining method. A comparative study between strain NEAU-Da3(T) and the type strains of the closest related species of the genus Streptomyces revealed that it differed from them in morphological, physiological and biochemical characteristics. Therefore, it is proposed that strain NEAU-Da3(T) represents a novel species of the genus Streptomyces, for which the name Streptomyces harbinensis sp. nov. is proposed. The type strain is NEAU-Da3(T) ( = CGMCC 4.7047(T) = DSM 42076(T)).


Assuntos
Glycine max/microbiologia , Lactamas/metabolismo , Filogenia , Streptomyces/classificação , Técnicas de Tipagem Bacteriana , China , DNA Bacteriano/genética , Ácidos Graxos/análise , Funções Verossimilhança , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fosfolipídeos/análise , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Streptomyces/genética , Streptomyces/isolamento & purificação , Vitamina K 2/análogos & derivados , Vitamina K 2/análise
6.
Antonie Van Leeuwenhoek ; 103(2): 399-408, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23011010

RESUMO

A novel endophytic actinomycete, designated strain NEAU-J3(T), was isolated from soybean root (Glycine max (L.) Merr) and characterized using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences suggested that strain NEAU-J3(T) fell within the family Micromonosporaceae. The strain was observed to form an extensively branched substrate mycelium, which carried non-motile oval spores with a smooth surface. The cell walls of strain NEAU-J3(T) were determined to contain meso-diaminopimelic acid and galactose, ribose and glucose were detected as whole-cell sugars. The major menaquinones were determined to be MK-9(H(4)) and MK-9(H(6)). The phospholipids detected were phosphatidylcholine and phosphatidylethanolamine. The major cellular fatty acids were determined to be C(16:0), C(18:1) ω9c, C(18:0), C(17:0), C(17:1) ω7c, anteiso-C(17:0), C(16:1) ω7c and C(15:0). The DNA G + C content was 62.5 mol%. On the basis of the morphological and chemotaxonomic characteristics, phylogenetic analysis and characteristic patterns of 16S rRNA gene signature nucleotides, strain NEAU-J3(T) is considered to represent a novel species of a new genus within the family Micromonosporaceae, for which the name Wangella harbinensis gen. nov., sp. nov. is proposed. The type strain of Wangella harbinensis is strain NEAU-J3(T) (=CGMCC 4.7039(T) = DSM 45747(T)).


Assuntos
Endófitos/classificação , Endófitos/isolamento & purificação , Glycine max/microbiologia , Micromonosporaceae/classificação , Micromonosporaceae/isolamento & purificação , Composição de Bases , Carboidratos/análise , Parede Celular/química , Análise por Conglomerados , Citosol/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácido Diaminopimélico/análise , Endófitos/genética , Ácidos Graxos/análise , Micromonosporaceae/genética , Dados de Sequência Molecular , Fosfolipídeos/análise , Filogenia , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análise
8.
Chem Sci ; 14(42): 11830-11839, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37920330

RESUMO

In seawater, severe hydroxide-based precipitation on the hydrogen evolution reaction (HER) electrode surface is still a major stumbling block for direct seawater electrolysis. Here, we design a direct seawater HER electrode with excellent anti-precipitation performance based on an Ni(OH)2 nanofiltration membrane in situ grown on nickel foam (NF) at room temperature. The positively charged Ni(OH)2 membrane with nanometer-scale cracks realises an ion sieving function, which apparently hinders the transfer of Mg2+/Ca2+ ions to suppress precipitation, while rapidly transporting OH- and H2O to ensure HER mass transfer. Therefore, the Ni(OH)2-membrane-decorated seawater HER electrode reduces precipitation by about 98.3% and exhibits high activity and stability. Moreover, in the application of a direct seawater electrolyser and magnesium seawater battery, the Ni(OH)2 membrane-decorated electrode also shows low precipitation and high stability. This work highlights a potential strategy to solve HER electrode precipitation in seawater via an ingenious electrode structure design.

9.
Environ Sci Pollut Res Int ; 30(16): 47248-47261, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36737565

RESUMO

China faces increasing health risks from climate change. The structure and function of the eye and vision were affected by extreme heat and cold. The study aimed to evaluate the impacts of heatwaves and cold spells on glaucoma. A national cross-sectional study of the Rural Epidemiology for Glaucoma (REG-China) was conducted in ten provinces of China, and 36,081 adults aged 40 years or more were included. Glaucoma signs were assessed via a standard examination. A total of 15 heatwave definitions, based on intensity (95th to 99th percentiles of temperature distribution) and duration (≥2 days, 3 days, and 4 days), were used to quantify heatwave effects, and 6 cold spell definitions were defined based on threshold temperature percentile (5th and 10th) and duration (3 days, 5 days, and 9 days). Multivariable-adjusted logistic regression models paired with interaction analysis were performed to investigate the impacts of heatwaves and cold spells on glaucoma, and the dose-response relationships were assessed using a restricted cubic spline (RCS) model. Subgroup analysis was conducted stratified by gender, age, smoking status, occupation, and family history of glaucoma. The overall prevalence of glaucoma was 2.1% (95% CI 1.94-2.25%). Higher heatwaves were significantly correlated with higher OR of glaucoma, with the OR (95% CI) ranging from 1.014 (1.009, 1.018) to 1.090 (1.065, 1.115) by different definitions. Glaucoma was affected by heatwaves more strongly than by cold spells. The effects of both heatwaves and cold spells were higher in males than females and in smokers than nonsmokers. These results of the present study evoked the attention of prospective research to elucidate the relationship between extreme temperatures and eye diseases.


Assuntos
Temperatura Baixa , Glaucoma , Adulto , Masculino , Feminino , Humanos , Estudos Transversais , Estudos Prospectivos , Temperatura Alta , China/epidemiologia , Glaucoma/epidemiologia
10.
Environ Pollut ; 316(Pt 1): 120701, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36423888

RESUMO

Studies exploring the association of tetrabromobisphenol A (TBBPA) with breast cancer and related mechanisms are limited. To investigate the relationship between TBBPA levels in breast adipose and breast cancer, we carried out case-control research. As well as further examine the mediating role of adipose metabolites between TBBPA and breast cancer using the metabolomics approach. In this study, the concentration of TBBPA was determined utilizing ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) after a solid phase extraction (SPE) pretreatment. High-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) was employed to analyze adipose metabolomics. Evaluation of metabolites linked to TBBPA exposure and breast cancer was performed utilizing mediation analysis. With an estimated OR (95%CI) of 1.153 (1.023, 1.299), TBBPA was firmly linked with breast cancer. We also used propensity score matching analysis and sensitivity analysis to reduce the effect of confounding factors on the results. Metabolomics of adipose suggested significant perturbation in the linoleic acid metabolism pathway. In addition, for PC (16:0/16:0) as phospholipids, a mediation effect on the associations of TBBPA exposure with breast cancer risks was observed (estimated mediation percentage: 56.58%). Understanding the relationship between TBBPA exposure and the risk of breast cancer may be facilitated by the findings, which point to potential mediation metabolites.


Assuntos
Neoplasias da Mama , Retardadores de Chama , Bifenil Polibromatos , Humanos , Feminino , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem , Retardadores de Chama/análise , Estudos de Casos e Controles , Bifenil Polibromatos/análise , China
11.
Sci Total Environ ; 751: 141813, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32898747

RESUMO

Conventional interpolation methods, such as spatial averaging, nearest neighbor, inverse distance weight and ordinary Kriging (OK); for estimating the spatial distribution of ground-level particulate matter (PM) data, do not account for the wind direction for estimating the spatial distribution of PM2.5. In this work, an interpolation algorithm, Win-OK accounting for the wind direction, is developed. In contrast to ordinary Kriging where all locations (irrespective of the wind direction) in the vicinity of a site is considered, the new algorithm (Win-OK) predicts the value at a certain location based on the measured values at locations upwind as determined by the wind direction. This new methodology, Win-OK is validated by applying it to analyze the hourly spatial distribution of ground-level PM2.5 concentrations during Chinese New Year and Chinese National Day in 2017 in Xinxiang city, China. The performance of OK and Win-OK are compared by using them to build PM2.5 concentration heat-maps. A "leave-one-out" cross validation methodology is used to calculate the root-mean-square error (RMSE) and standard deviation for evaluating both algorithms. The results show that OK sometimes gives an extremely high RMSE value using a Gaussian semi-variance model, and the standard deviation significantly deviates from the measured values. Win-OK was found to more accurately predict the PM2.5 spatial distribution in a specific sector. The performance of Win-OK is more stable than OK as established by comparing the calculated RMSE and standard deviation from predictions of both algorithms. Win-OK with a spherical semi-variance model is the most accurate method investigated here for deriving the spatial distribution of ground-level PM2.5. The new algorithm developed here could improve the prediction accuracy of PM2.5 spatial distribution by considering the effect of wind direction.

12.
ACS Appl Mater Interfaces ; 12(22): 24683-24692, 2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32379414

RESUMO

Rational electrode design is crucial to promote the performance of the hydrogen evolution reaction (HER) via further enhancing the activity, stability, and utilization of platinum (Pt) in an alkaline electrolyte. Herein, a binder-free low-Pt-content HER electrode, Pt (∼20 µg cm-2) decorated on nickel hydroxide grown on nickel foam (Pt-Ni(OH)2-2h-NF20), is fabricated at near room temperature in a test tube. To lower the ohmic resistance, for the first time, the Pt nanoparticles were location-selectively anchored on the bottom of height-controlled vertical Ni(OH)2 nanosheets via utilizing the mass transfer resistance of the dense Ni(OH)2 film for chloroplatinate. Furthermore, the excellent mass transfer, high specific surface area of Pt, synergistic effect between Pt with Ni(OH)2, and stable structure together prompt the resulting electrode with a special structure to exhibit superior HER electrocatalytic activity and stability in 1 M KOH. Typically, this electrode reaches a current density of 35.9 mA cm-2 at an overpotential of 100 mV, which is over 8 times higher than that of commercial Pt/C, and the overpotential only increases by 20 mV at 100 mA cm-2 over 150,000 s of stability test. Benefiting from the simple fabrication process, the electrode with an area of 840 cm2 was successfully prepared with a steady overpotential of 370 mV at 1000 mA cm-2 and increased potential of 23 mV over 50 h of stability test.

13.
Front Microbiol ; 9: 135, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29467744

RESUMO

Marine microorganisms and their extracellular enzymes (ECEs) play an important role in the remineralization of organic material by hydrolyzing high-molecular-weight substrates to sizes sufficiently small to be transported through cell membrane, yet the diversity of the enzyme-producing bacteria and the types of ECEs involved in the degradation process are largely unknown. In this work, we investigated the diversity of cultivable bacteria and their ECEs and the potential activities of aminopeptidase in the water column at eight different depths of the New Britain Trench. There was a great diversity of cultivable bacteria and ECEs, and depth appears an important driver of the diversity. The 16S rRNA sequence analysis revealed that the cultivable bacteria were affiliated mostly with the phyla Proteobacteria and Actinobacteria, and the predominant genera were Pseudoalteromonas (62.7%) and Halomonas (17.3%). Moreover, 70.7% of the isolates were found to produce hydrolytic zone on casein and gelatin plates, in which Pseudoalteromonas was the predominant group, exhibiting relatively high protease production. Inhibitor analysis showed that the extracellular proteases from the isolated bacteria were serine proteases in the surface water and metalloproteases in the deep water. Meanwhile, the Vmax and Km of aminopeptidase exhibited a maximum in the surface water and low values in the deep bathy- and abyssopelagic water, indicating lower rates of hydrolysis and higher substrate affinity in the deeper waters. These results shed new insights into the diversity of the cultivable bacteria and bacterial ECEs and their likely biogeochemical functions in the trench environment.

14.
Front Microbiol ; 9: 625, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29670597

RESUMO

Particle-attached (PA) and free-living (FL) microorganisms play significant but different roles in mineralization of organic matter (OM) in the ocean. Currently, little is known about PA and FL microbial communities in bathyal and abyssal pelagic waters, and understanding of their diversity and distribution in the water column and their interactions with environmental factors in the trench area is limited. We investigated for the first time the variations of abundance and diversities of the PA and FL bacterial communities in the epi-, bathy-, and abyssopelagic zones of the New Britain Trench (NBT). The PA communities showed decreasing species richness but increasing relative abundance with depth, suggesting the increasing ecological significance of the PA bacteria in the deep ocean. The abundance and diversity of PA and FL bacterial communities in the NBT water column appeared to be shaped by different sets of environment factors, which might be related to different micro-niches of the two communities. Analysis on species distribution suggested that the differences between PA and FL bacteria communities mainly resulted from the different relative abundance of the "shared taxa" in the two types of communities. These findings provide valuable information for understanding the relative ecological roles of the PA and FL bacterial communities and their interactions with environmental factors in different pelagic zones along the vertical profile of the NBT water column.

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