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1.
Plant Physiol ; 189(1): 204-214, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35099552

RESUMO

The hydraulic vulnerability segmentation (HVS) hypothesis implies the existence of differences in embolism resistance between plant organs along the xylem pathway and has been suggested as an adaptation allowing the differential preservation of more resource-rich tissues during drought stress. Compound leaves in trees are considered a low-cost means of increasing leaf area and may thus be expected to show evidence of strong HVS, given the tendency of compound-leaved tree species to shed their leaf units during drought. However, the existence and role of HVS in compound-leaved tree species during drought remain uncertain. We used an optical visualization technique to estimate embolism occurrence in stems, petioles, and leaflets of shoots in two compound-leaved tree species, Manchurian ash (Fraxinus mandshurica) and Manchurian walnut (Juglans mandshurica). We found higher (less negative) water potentials corresponding to 50% loss of conductivity (P50) in leaflets and petioles than in stems in both species. Overall, we observed a consistent pattern of stem > petiole > leaflet in terms of xylem resistance to embolism and hydraulic safety margins (i.e. the difference between mid-day water potential and P50). The coordinated variation in embolism vulnerability between organs suggests that during drought conditions, trees benefit from early embolism and subsequent shedding of more expendable organs such as leaflets and petioles, as this provides a degree of protection to the integrity of the hydraulic system of the more carbon costly stems. Our results highlight the importance of HVS as an adaptive mechanism of compound-leaved trees to withstand drought stress.


Assuntos
Embolia , Juglans , Secas , Folhas de Planta , Caules de Planta , Árvores , Água , Xilema
2.
Opt Express ; 31(26): 43975-43988, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38178480

RESUMO

Pancharatnam-Berry (PB) phase, usually utilized for phase manipulation of circularly polarized (CP) waves, has inherent symmetrical response on left-handed polarized (LCP) and right-handed polarized (RCP) for orbital angular momentum (OAM), which severely hinders its application. By modulating both propagation and PB phase allows independent control of LCP and RCP of OAM, but increases the design difficulty. Here, we propose a phase compensation scheme to independent control the CP states of OAM only utilizing PB phase, where arbitrary topological charges and deflection directions of LCP and RCP beams can be realized. Two wideband metasurfaces are designed to independent control the mode, circular polarization and beam directions of OAM at the frequency range of 10-20 GHz. This work significantly motivates the development of polarization division multiplexing in wireless communication system.

3.
BMC Med Educ ; 23(1): 271, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37081506

RESUMO

BACKGROUND: English as a Media of Instruction (EMI) teacher development project is based upon the framework for teacher Continuing Professional Development (CPD) and aims to effectively improve both the confidence and overall capacity of EMI lecturers. Kunming Medical University(KMU) conducted the EMI training project to improve teachers' competence for MBBS education. This study aimed to assess teachers' changes following the implementation of this training project, via the Kirkpatrick evaluation model. METHODS: A total of trainees (n = 84) were invited as the research objects. The effects of the EMI training project implemented in KMU were evaluated in terms of the reaction, learning, and behavior dimensions based on the Kirkpatrick model. The self-administered online anonymous questionnaires and observations of participants' EMI lectures were administered to all participants to collect the data. Furthermore, to understand participants' perceptions of the management and trainers of the training project, some open-ended questions were required to answer. RESULTS: Based on 1-3 level of the Kirkpatrick model, all participants were highly satisfied with the EMI training implementation on the reaction level, and expressed positive comments about the management of the training and trainers. On the learning level, participants' scores on awareness of EMI teaching techniques increased significantly(t = 7.122, P < 0.001)with the training process. Concerning the behavior level, the participant's confidence as an EMI instructor increased dramatically at end of the whole training(p < 0.001). Moreover, trainees had applied some EMI skills in class and would like to make some commitment to implement learner-centered learning, to do more practice on EMI techniques. CONCLUSION: The findings of this study confirm that EMI training has an effective impact on the competence and confidence of participants as EMI instructors at levels 1-3 of the Kirkpatrick evaluation model. This training may be a potentially beneficial effect on the teaching quality of MBBS education.


Assuntos
Currículo , Aprendizagem , Humanos , Escolaridade , Competência Clínica , Inquéritos e Questionários
4.
Prenat Diagn ; 42(1): 37-48, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34699084

RESUMO

OBJECTIVE: We aimed to compare perinatal outcomes between umbilical cord occlusion techniques in monochorionic pregnancies, including umbilical cord ligation, fetoscopic laser coagulation, interstitial laser coagulation, bipolar cord occlusion, radiofrequency ablation, and microwave ablation. METHODS: This study was registered with PROSPERO (CRD42020158861). PubMed, Web of Science, Cochrane Library, and Embase were searched for studies published up to May 2020. The DerSimonian-Laird random-effects model was used for the meta-analysis. Subgroup analyses were performed to compare the outcomes among the six techniques. Meta-regression was used to adjust for confounders. RESULTS: Thirty-four studies with 1646 participants were included. The overall survival was 76.5% after umbilical cord ligation, 78.8% after fetoscopic laser coagulation, 60.3% after interstitial laser coagulation, 79.2% after bipolar cord occlusion, 77.5% after radiofrequency ablation, and 75.0% after microwave ablation. Subgroup comparison showed the rates of overall survival and preterm premature rupture of membranes were not significant different among six techniques. However, rates of fetal loss, premature birth, live birth, and neonatal death differed significantly among the six groups. CONCLUSIONS: The choice of umbilical cord occlusion techniques will affect perinatal outcomes. We suggested that the choice of umbilical cord occlusion techniques should fully consider these differences among techniques.


Assuntos
Aborto Induzido/normas , Oclusão Terapêutica/métodos , Cordão Umbilical/cirurgia , Aborto Induzido/métodos , Adulto , Feminino , Humanos , Gravidez , Resultado da Gravidez/epidemiologia , Oclusão Terapêutica/normas
5.
New Phytol ; 219(2): 530-541, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29682759

RESUMO

Some temperate tree species mitigate the negative impacts of frost-induced xylem cavitation by restoring impaired hydraulic function via positive pressures, and may therefore be more resistant to frost fatigue (the phenomenon that post-freezing xylem becomes more susceptible to hydraulic dysfunction) than nonpressure-generating species. We test this hypothesis and investigate underlying anatomical/physiological mechanisms. Using a common garden experiment, we studied key hydraulic traits and detailed xylem anatomical characteristics of 18 sympatric tree species. These species belong to three functional groups, that is, one generating both root and stem pressures (RSP), one generating only root pressure (RP), and one unable to generate such pressures (NP). The three functional groups diverged substantially in hydraulic efficiency, resistance to drought-induced cavitation, and frost fatigue resistance. Most notably, RSP and RP were more resistant to frost fatigue than NP, but this was at the cost of reduced hydraulic conductivity for RSP and reduced resistance to drought-induced cavitation for RP. Our results show that, in environments with strong frost stress: these groups diverge in hydraulic functioning following multiple trade-offs between hydraulic efficiency, resistance to drought and resistance to frost fatigue; and how differences in anatomical characteristics drive such divergence across species.


Assuntos
Congelamento , Raízes de Plantas/fisiologia , Caules de Planta/fisiologia , Pressão , Árvores/fisiologia , Água/fisiologia , Análise de Componente Principal , Característica Quantitativa Herdável , Especificidade da Espécie , Madeira/fisiologia , Xilema/fisiologia , Xilema/ultraestrutura
6.
Physiol Plant ; 163(2): 183-195, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29193125

RESUMO

Elevated tropospheric ozone (O3 ) concentration has been shown to affect many aspects of plant performance including detrimental effects on leaf photosynthesis and plant growth. However, it is not known whether such changes are accompanied by concomitant responses in plant hydraulic architecture and water relations, which would have great implications for plant growth and survival in face of unfavorable water conditions. A soybean (Glycine max (L.) Merr.) cultivar commonly used in Northeast China was exposed to non-filtered air (NF, averaged 24.0 nl l-1 ) and elevated O3 concentrations (eO3 , 40 nl l-1 supplied with NF air) in six open-top chambers for 50 days. The eO3 treatment resulted in a significant decrease in whole-plant hydraulic conductance that is mainly attributable to the reduced hydraulic conductance of the root system and the leaflets, while stem and leaf petiole hydraulic conductance showed no significant response to eO3 . Stomatal conductance of plants grown under eO3 was lower during mid-morning but significantly higher at midday, which resulted in substantially more negative daily minimum water potentials. Moreover, excised leaves from the eO3 treated plants showed significantly higher rates of water loss, suggesting a lower ability to withhold water when water supply is impeded. Our results indicate that, besides the direct detrimental effects of eO3 on photosynthetic carbon assimilation, its influences on hydraulic architecture and water relations may also negatively affect O3 -sensitive crops by deteriorating the detrimental effects of unfavorable water conditions.


Assuntos
Glycine max/fisiologia , Ozônio/análise , Transpiração Vegetal/fisiologia , Água/metabolismo , Fotossíntese , Folhas de Planta/fisiologia
7.
Molecules ; 23(12)2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30567366

RESUMO

Promoting the browning of white fat may be a potential means of combating obesity. Therefore, in this study, we investigated the effect of resveratrol (RES) on the body weight and browning of white fat in high-fat diet (HFD)-induced obese mice and the potential associated mechanism in vivo. Eight-week-old male mice were randomized to receive different treatments: (1), chow without any additional treatment (chow); (2), chow plus 0.4% resveratrol (chow-RES); (3), HFD without any additional treatment (HFD); and (4), HFD plus 0.4% resveratrol (HFD-RES). After 4 weeks of feeding, additional 8-week-old male recipient mice were randomly allocated to the following 4 treatments: (5), HFD and received feces from chow-fed mice; (6), HFD and received feces from chow-RES-fed mice; (7), HFD and received feces from HFD-fed mice; and (8), HFD and received feces from HFD-RES-fed mice. RES treatment significantly inhibited increases in fat accumulation, promoted the browning of white adipose tissue (WAT) and alleviated gut microbiota dysbiosis in HFD-fed mice. Subsequent analyses showed that the gut microbiota remodeling induced by resveratrol had a positive role in WAT browning, and sirtuin-1 (Sirt1) signaling appears to be a key component of this process. Overall, the results show that RES may serve as a potential intervention to reduce obesity by alleviating dysbiosis of the gut microbiota.


Assuntos
Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Obesidade/tratamento farmacológico , Resveratrol/farmacologia , Animais , Dieta Hiperlipídica/efeitos adversos , Masculino , Camundongos , Obesidade/etiologia , Distribuição Aleatória , Sirtuína 1/metabolismo
8.
Ecotoxicol Environ Saf ; 141: 160-170, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28342328

RESUMO

So far, few data are available on the reproductive toxicological assessment of ß-diketone antibiotics (DKAs), a class of ubiquitous pseudo-persistent pollutant, in zebrafish (Danio rerio). Herein, we reported the reproductive effects of DKAs by means of transcriptome analysis (F1-zebrafish), changes in a series of reproductive indices (F0-zebrafish) and histopathological observations. A total of 1170, 983 and 1399 genes were found to be differentially expressed when compared control vs. 6.25mg/L, control vs. 12.5mg/L and 6.25 vs. 12.5mg/L DKA-exposure treatments, respectively. Among three comparison groups, 670, 569 and 821 genes were respectively assigned for GO analyses based on matches with sequences of known functions. In 149 KEGG-noted metabolic pathways, the preferential one was the MAPK (mitogen-activated protein kinase) signaling pathway, followed by oxidative phosphorylation, neuroactive ligand-receptor interaction and so on. By qPCR verification, 6 genes (c6ast4, igfbp1b, mrpl42, tnnc2, emc4 and ddit4) showed consistent gene expression with those identified by transcriptome sequencing. Due to DKA-exposure, the concentrations of plasma estradiol and testosterone, and the gonado-somatic index were significantly dose-dependently declined. Also, DKA-exposure led to declining in zebrafish reproductive capacity, reflecting in fertilization, hatchability and egg production. Histopathological observations demonstrated that zebrafish ovary and testis suffered serious damage after DKA-exposure. The 4-oxo-TEMP signals increased obviously with increasing DKA-exposed concentrations, implying disruption of balance between generation and clearance of 1O2. In summary, DKAs not only produce reproductive toxicological effects on F0-zebrafish, but also result in adverse consequences for growth and development of F1-zebrafish.


Assuntos
Antibacterianos/toxicidade , Fluoroquinolonas/toxicidade , Reprodução/efeitos dos fármacos , Tetraciclinas/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/genética , Animais , Antibacterianos/química , Feminino , Fluoroquinolonas/química , Perfilação da Expressão Gênica , Masculino , Anotação de Sequência Molecular , Reprodução/genética , Tetraciclinas/química , Transcriptoma/efeitos dos fármacos , Poluentes Químicos da Água/química , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
9.
Environ Toxicol ; 31(6): 736-50, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25504783

RESUMO

Fluoroquinolones (FQs) and tetracyclines (TCs), the two ß-diketone antibiotics (DKAs), are two frequently detected pollutants in the environment; however, little data are available on their combined toxicity to zebrafish (Danio rerio). This study reports that toxicologic effects of combined DKA (FQs-TCs) exposure on zebrafish were comparable with or slightly less than those of TCs alone, showing that TCs played a major toxicologic role in the mixtures. The effects of FQs, TCs, and DKAs on malformation rates of zebrafish were dose dependent, with EC50 values of 481.3, 16.4, and 135.1 mg/L, respectively. According to the combined effects of DKAs on zebrafish hatching, mortality, and malformation rates, the interaction between FQs and TCs was shown to be antagonistic based on three assessment methods: Toxic Unit, Additional Index, and Mixture Toxic Index. The 1.56 mg/L TC and 9.38 mg/L DKA treatments resulted in higher zebrafish basal swimming rate compared with the control group at 120 hours postfertilization (hpf). in both light and light-to-dark photoperiod experiments. Under conditions of no obvious abnormality in cardiac development, the heart beats were decreased significantly because of DKA exposure, such as decreasing by ∼20% at 150 mg/L DKAs. Transmission electron microscopy observation of myocytes from DKA-exposed hearts displayed prominent interruptions and myofibrillar disorganization of the normal parallel alignment of thick and thin filaments, and partial edematous and dissolved membranes of cell nuclear tissues. At 90 mg/L DKAs, the transcriptional levels of the acta1a, myl7, and gle1b genes, related to heart development and skeletal muscle formation, were significantly changed. This is consistent with the swimming behavior and histopathologic results obtained by transmission electron microscopy. In summary, the toxicity of the combined DKAs to zebrafish was comparable with or less than that of TCs alone and had the ability to impair individual behaviors that are of great importance in the assessment of their ecologic fitness. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 736-750, 2016.


Assuntos
Antibacterianos/toxicidade , Fluoroquinolonas/toxicidade , Tetraciclinas/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Embrião não Mamífero/efeitos dos fármacos , Peixe-Zebra/embriologia , Proteínas de Peixe-Zebra/metabolismo
10.
Environ Toxicol ; 31(11): 1357-1371, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25846866

RESUMO

Transcriptome analysis is important for interpreting the functional elements of the genome and revealing the molecular constituents of cells and tissues. Herein, differentially transcribed genes were identified by deep sequencing after zebrafish (Danio rerio) were exposed to ß-diketone antibiotics (DKAs); 23,129 and 23,550 mapped genes were detected in control and treatment groups, a total of 3238 genes were differentially expressed between control and treatment groups. Of these genes, 328 genes (213 up- and 115 down-regulation) had significant differential expression (p < 0.05) and an expression ratio (control/treatment) of >2 or <0.5. Additionally, we performed Gene Ontology (GO) category and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses, and found 266 genes in the treatment group with annotation terms linked to the GO category. A total of 77 differentially expressed transcriptional genes were associated with 132 predicted KEGG metabolic pathways. Serious liver tissue damage was reflected and consistent with the differences in genetic classification and function from the transcriptome analysis. These results enhance our understanding of zebrafish developmental processes under exposure to DKA stress. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1357-1371, 2016.


Assuntos
Antibacterianos/toxicidade , Cetonas/toxicidade , Transcriptoma/efeitos dos fármacos , Animais , Antibacterianos/química , Regulação para Baixo/efeitos dos fármacos , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Cetonas/química , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Microscopia Eletrônica , Análise de Sequência de RNA , Regulação para Cima/efeitos dos fármacos , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
11.
J Phycol ; 50(5): 829-36, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26988638

RESUMO

The removal efficiency of Cu(2+) by Spirulina platensis (strain FACHB-834), in viable and heat-inactivated forms, was investigated in the presence and absence of linear alkylbenzene sulfonate (LAS). When the initial Cu(2+) concentration was in the range of 0.5-1.5 mg · L(-1) , a slight increase in growth rate of FACHB-834 was observed. In contrast, when Cu(2+) or LAS concentrations were at or higher than 2.0 or 6.0 mg · L(-1) , respectively, the growth of FACHB-834 was inhibited and displayed yellowing and fragmentation of filaments. The presence of LAS improved Cu(2+) removal by ~20%, and accelerated attainment of Cu(2+) retention equilibrium. For the 2- mg · L(-1) Cu(2+) treatments, retention equilibrium occurred within 2 d and showed maximum Cu(2+) removal of 1.83 mg · L(-1) . In the presence of LAS, the ratio of extracellular bound Cu(2+) to intracellular Cu(2+) taken up by the cells was lower (1.05-2.26) than corresponding ratios (2.46-7.85) in the absence of LAS. The percentages of extracellular bound Cu(2+) to total Cu(2+) removal (both bound and taken up by cells) in the presence of LAS ranged from 51.2% to 69.3%, which was lower than their corresponding percentages (71.1%-88.7%) in the absence of LAS. LAS promoted biologically active transport of the extracellular bound form of Cu(2+) into the cell. In contrast, the addition of LAS did not increase the maximum removal efficiency of Cu(2+) (61.4% ± 5.6%) by heat-inactivated cells compared to that of living cells (59.6% ± 6.0%). These results provide a theoretical foundation for designing bioremediation strategies using FACHB-834 for use in surface waters contaminated by both heavy metals and LAS.

12.
Tree Physiol ; 43(5): 722-736, 2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-36715627

RESUMO

In cold and humid temperate forests, low temperature, late frost and frequent freeze-thaw cycles are the main factors limiting tree growth and survival. Ring- and diffuse-porous tree species differing in xylem anatomy coexist in these forests, but their divergent adaptations to these factors have been poorly explored. To fill this knowledge gap, we compared four ring-porous and four diffuse-porous tree species from the same temperate forest in Northeast China by quantifying their leaf and stem functional traits, their stem growth rates using tree ring analysis and their resistance to cold represented by upper altitude species distribution borders from survey data. We found that the ring-porous trees were characterized by traits related to more rapid water transport, carbon gain and stem growth rates than those of the diffuse-porous species. Compared with the diffuse-porous species, the ring-porous species had a significantly higher shoot hydraulic conductance (Ks-shoot, 0.52 vs 1.03 kg m-1 s-1 MPa-1), leaf photosynthetic rate (An, 11.28 vs 15.83 µmol m-2 s-1), relative basal area increment (BAIr, 2.28 vs 0.72 cm year-1) and stem biomass increment (M, 0.34 vs 0.09 kg year-1 m-1). However, the observed upper elevational distribution limit of the diffuse-porous species was higher than that of the ring-porous species and was associated with higher values of conservative traits, such as longer leaf life span (R2 = 0.52). Correspondingly, BAIr and M showed significant positive correlations with acquisitive traits such as Ks-shoot (R2 = 0.77) and leaf photosynthetic rate (R2 = 0.73) across the eight species, with the ring-porous species occurring at the fast-acquisitive side of the spectrum and the diffuse-porous species located on the opposite side. The observed contrasts in functional traits between the two species groups improved our understanding of their differences in terms of growth strategies and adaptive capabilities in the cold, humid temperate forests.


Assuntos
Florestas , Árvores , Porosidade , Xilema , Folhas de Planta , Água
13.
Aquat Toxicol ; 264: 106733, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37875383

RESUMO

The present study was undertaken to explore the effects of sulfamethazine (SMZ) dietary exposure on the enrichment of the intestine microbial structure, and antibiotic resistance gene (ARGs) transmission in marine medaka, with respect to antibiotic dose, duration, and sex. In male fish, a dietary exposure of 10 µg/L SMZ led to a heightened SMZ enrichment in the intestine, whereas metabolite (N-SMZ) levels were elevated at a higher exposure concentration (100 µg/L). Conversely, female fish exhibited stable levels of accumulation and metabolic rates across the exposure period. The composition of intestinal microorganisms revealed that exposure duration exerted a greater impact on the abundance and diversity of gut microbes, and microbial responses to SMZ varied across exposure time points. The expansion of Bacteroidetes and Ruegeria likely stimulated SMZ metabolism and contributed to the more balanced level of SMZ and N-SMZ observed in females. In males, short-term SMZ stress resulted in a disruption of intestinal homeostasis, while the rise in the abundance of the Fusobacteria and Propionigeniuma suggested a potential enhancement in intestinal anti-inflammatory capacity over time. Overall, female medaka exhibited greater adaptability to SMZ, and males appear to experience prolonged effects due to SMZ. A total of 11 ARGs and 5 mobile genetic elements (MGEs) were identified. Ruegeria is the main carrier of two types of MGEs (IS1247, ISSm2-Xanthob), and may serve as an indicator of ARG transmission. Therefore, it is rational to consider some fish breeding areas in natural waters as potential "reservoirs" of antibiotic resistance. This research will provide a valuable reference for the transmission of drug resistance along the food chain.


Assuntos
Sulfametazina , Poluentes Químicos da Água , Animais , Feminino , Masculino , Exposição Dietética , Poluentes Químicos da Água/toxicidade , Antibacterianos/farmacologia , Homeostase
14.
Chemosphere ; 309(Pt 2): 136738, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36216115

RESUMO

Antibiotics are widely consumed in the intensive mariculture industry. A better understanding of the effect of antibiotics on intergenerational antibiotic resistance in organisms is urgent since intergenerational transmission is crucial for the spread of antibiotic resistance genes (ARGs) in the environment. Herein, marine medaka (Oryzias melastigma) chronically exposed to low doses of sulfamethazine (SMZ) hormetically affected the progeny, characterized by increased richness and diversity of fecal microbiota and intestinal barrier-related gene up-regulation. Progeny immunity was modulated and caused by genetic factors due to the absence of significant SMZ accumulation in F1 embryos. In addition, some of the top genera in the progeny were positively correlated with immune diseases, while the expression of some immune-related genes, such as TNFα, IL1R2, and TLR3 changed significantly. This further indicated that the host selection caused by changes in progeny immunity was probably the primary determinant of progeny intestinal microbial colonization. Metagenomic analysis revealed that Proteobacteria represented the primary carriers of ARGs, while parental SMZ exposure facilitated the distribution and enrichment of multiple ARGs involved in the antibiotic inactivation in the progeny by promoting the diversity of Gammaproteobacteria and Bacteroidetes, further illustrating that antibiotic selection pressure persisted even if the offspring were not exposed. Therefore, SMZ induced hormesis in the progeny at the expense of increasing antibiotic resistance. Collectively, these findings provide a comprehensive overview of the intergenerational effect of antibiotics and serve as a reminder that the ARG transmission induced by the intergenerational impact of antibiotics on organisms should not be ignored.


Assuntos
Antibacterianos , Fator de Necrose Tumoral alfa , Antibacterianos/toxicidade , Fator de Necrose Tumoral alfa/genética , Hormese , Sulfametazina , Receptor 3 Toll-Like/genética , Genes Bacterianos , Resistência Microbiana a Medicamentos/genética
15.
Environ Pollut ; 313: 120157, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36126771

RESUMO

Microplastics and antibiotics widely coexist in the aquatic environment, especially in mariculture regions. However, antibiotics adsorbed on microplastics and their role in the colonization of microorganisms on microplastics are poorly understood. Therefore, in-situ aging experiments were conducted to investigate the impact of antibiotics and microplastics co-occurrence on microorganisms and assess their potential risks to human health. Results showed that antibiotics were adsorbed selectively on microplastics, with 29 investigated antibiotics (n = 40) detected in surrounding water but only 6 investigated antibiotics were adsorbed on microplastics. The concentration of antibiotics accumulated on microplastics was controlled by microplastic types and environmental conditions. For example, aged polypropylene (PP) had more developed pore structures resulting in higher adsorption of antibiotics than other microplastic types. High-throughput sequencing showed higher diversity and distinct composition of microorganisms attached to the microplastics than the surrounding water. Opportunistic pathogenic bacteria such as Mycobacterium possessed positive relationships with tetracycline and doxycycline on aged microplastics, which showed adsorbed antibiotics on aged microplastics could benefit some specific pathogens colonized on the microplastics and spread into unaffected ecosystems, marine organisms even humans. The health risk quotient (HQ) implied the potential human health risk of consuming commercial seafood polluted by antibiotics and microplastic loaded with antibiotics. This study revealed the interaction of antibiotics and microorganisms with aged microplastics in aquaculture systems, providing a novel insight into their synergistic effects on ecological and human health.


Assuntos
Microplásticos , Poluentes Químicos da Água , Adsorção , Idoso , Antibacterianos/farmacologia , Bactérias , Doxiciclina , Ecossistema , Monitoramento Ambiental , Humanos , Plásticos , Polipropilenos/análise , Água , Poluentes Químicos da Água/análise
16.
Ying Yong Sheng Tai Xue Bao ; 33(3): 711-719, 2022 Mar.
Artigo em Zh | MEDLINE | ID: mdl-35524523

RESUMO

Ginkgo biloba is an important urban ornamental tree species, but poor growth and damages often occur in urban environments. As a street tree species, the decline and death of G. biloba is particularly frequent, with the relevant physiological mechanism being unclear. In this study, we compared hydraulic characteristics, non-structural carbohydrate (NSC) contents and health status between G. biloba trees growing along the streets and those in parks in Shenyang City. The results showed that G. biloba growing along the streets showed higher degrees of branch and leaf mortality than those growing in the parks. Branches of G. biloba growing in both conditions showed lower degrees of xylem embolism. Branch hydraulic vulnerable curves of G. biloba under the two growing conditions also showed no significant difference, with the average P50 being lower than -2.8 MPa. G. biloba growing along the streets had lower leaf area specific conductivity, smaller tracheid diameter, smaller hydraulic diameter, lower soluble sugar content and total NSC than those growing in parks. Hydraulic failure was not the direct reason for the decline and mortality of G. biloba growing along streets. Under the more stressed growth conditions along the streets, G. biloba had smaller tracheid diameters in stems and lower Huber values, which limited the ability of water transport and photosynthetic carbon assimilation at the whole branch level. In addition, in order to deal with more serious stress such as greater heat and drought stresses, G. biloba might need to invest more NSC to repair damage, which further decreaded NSC contents in branches and increased the risk of carbon imbalance. At the same habitat (street or park), xylem hydraulics and NSC contents of G. biloba also showed relatively large difference among sampling sites, which reflected large heterogeneity of urban environment for tree growth.


Assuntos
Ginkgo biloba , Xilema , Carboidratos , Carbono , Secas , Folhas de Planta/fisiologia , Árvores/fisiologia , Água/fisiologia , Xilema/fisiologia
17.
Huan Jing Ke Xue ; 43(11): 4810-4821, 2022 Nov 08.
Artigo em Zh | MEDLINE | ID: mdl-36437054

RESUMO

Human activities and global climate change have contributed substantially to the input of land-sourced pollutants into the aquatic environment, especially for emerging or newly identified contaminants, such as microplastics, emerging persistent organic pollutants, pharmaceuticals, and personal care products. The prevalence and toxicity of these emerging pollutants has raised continued concern for the health and safety of the public worldwide. A review of sources, distribution, interfacial transport processes of microplastics, per-and polyfluorinated compounds, antibiotics, and endocrine-disrupting chemicals and factors that influence their environmental behavior in the estuary-coastal environment have been included. The adverse ecological effects and health risks of these emerging contaminants to humans were also reviewed. Lastly, the direction of future research was provided regarding the environmental behavior of multiple emerging pollutants in the coastal environment and the health risks resulting from their interactions, supporting the prevention and control of marine pollution and the healthy development of the marine economy.


Assuntos
Disruptores Endócrinos , Poluentes Ambientais , Humanos , Estuários , Plásticos , Microplásticos , Disruptores Endócrinos/análise , Poluentes Ambientais/análise
18.
Chemosphere ; 265: 129053, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33272674

RESUMO

The plasticizer di (2-ethylhexyl) phthalate (DEHP) is becoming increasingly abundant throughout the global environment as plastic pollution becomes highly severe, especially in the ocean. The adverse effects of DEHP have garnered increasing concern as they are recognized as endocrine disruptors. However, information on the effects of DEHP in marine organisms remains limited. In this study, acute toxic effects on marine medaka (Oryzias melastigma) following DEHP exposure were investigated. Transcriptome analysis was performed on the livers of medaka exposed to DEHP for 6 and 24 h. Results showed that 1595 genes were affected in all the analyzed specimens, and several genes expressed variably according to sex. Some pathways associated with immunity, metabolism, and endocrine system were significantly enriched, with the complement system appearing to be the most affected immune pathway. Pathway enrichment indicated that, under acute DEHP exposure, the immune response of females tended to be more sensitive than that of males. In addition, ferroptosis occurred in response to DEHP exposure, which resulted in an enrichment of the ferroptosis pathway along with iron overload, an increase in malondialdehyde (MDA) and lipid peroxidation (LPO) content, and a decrease in glutathione (GSH) levels. These results indicate that a form of cell death characterized by iron-dependence occurred following DEHP exposure, but the underlying mechanism requires further analysis. This study implies that DEHP can alter some molecular regulation patterns within a short period and induce cell death through ferroptosis.


Assuntos
Dietilexilftalato , Oryzias , Animais , Dietilexilftalato/toxicidade , Feminino , Ferroptose , Masculino , Oryzias/genética , Ácidos Ftálicos , Plastificantes
19.
Ann N Y Acad Sci ; 1493(1): 90-101, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33455003

RESUMO

The Chinese government has established a three-tier maternal care system covering the entire country and providing integrated antenatal care (ANC) for pregnancies. This study aimed to analyze the direct and indirect effects of ANC services on early childhood development. A community-based cross-sectional survey was conducted for mothers' ANC visits and assessments of early childhood development in Shanxi and Guizhou provinces, China. A total of 1660 mother-child dyads were included in current analyses: 29.2% of mothers did not receive any ANC (ANC1), 23.3% of mothers received ANC three or fewer times (ANC2), and 47.5% of mothers received ANC four or more times (ANC3). Children whose mothers received ANC services had a significantly lower risk of overall developmental delay (OR = 0.60, 95% CI: 0.44-0.81 for ANC2; and OR = 0.44, 95% CI: 0.34-0.59 for ANC3) and social-emotional developmental delay (OR = 0.68, 95% CI: 0.49-0.94 for ANC3). Furthermore, a significant pathway relationship mediated by maternal depression and nurturing care was found between ANC and developmental delay. This study showed ANC services significantly reduced the risk of developmental delay in offspring. We also suggest that a nationwide ANC system can be a good delivery platform for scaled-up early childhood development interventions.


Assuntos
Desenvolvimento Infantil , Serviços de Saúde Materna , Cuidado Pré-Natal/métodos , Adulto , Pré-Escolar , China , Estudos Transversais , Feminino , Promoção da Saúde/métodos , Humanos , Lactente , Masculino , Relações Mãe-Filho , Mães , Gravidez , Inquéritos e Questionários
20.
Int Breastfeed J ; 16(1): 40, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001155

RESUMO

BACKGROUND: Breast milk is the best source of essential nutrients and bioactive components for infants under 6 months. However, little is known about what affects breastfeeding intentions and practices of Chinese mothers. With measures of individual, setting, and sociocultural factors, this study examined determinants of exclusive breastfeeding in the first 6 months of infancy in China. METHODS: Data were obtained from a national cross-sectional survey in China in 2018 that included 5237 infants under 6 months with available measurements of breastfeeding. A 24-h reported food recall method was applied to assess breastfeeding and complementary food intake in the past 24 h. Potential breastfeeding determinants categorized into six aspects were measured: (1) infant health, (2) maternal sociodemographic characteristics, (3) maternal health, (4) breastfeeding support from family, friends, and workplace, (5) social support for breastfeeding, and (6) maternal breastfeeding experiences and knowledge. Reasons for non-commencement or early cessation of breastfeeding were evaluated for non-breastfed infants. For breastfed infants, multivariate logistic regression was used to explore the determinants of exclusive breastfeeding. RESULTS: About 30 % (29.5%) of infants under 6 months were exclusively breastfed; 2.3% (2.3%) had never been breastfed and 3.2% had ceased breastfeeding. No breast milk (60.7%), maternal illness (13.9%), and infant illness (13.1%) were the top three reasons for non-commencement of breastfeeding. Insufficient breast milk was the reason given for ceasing breastfeeding early by almost two thirds of caregivers who had stopped breastfeeding. The following factors were associated with exclusive breastfeeding: maternal higher education, formal employment with ≥6 months of paid maternity leave, support of the husband and best friends for breastfeeding, a breastfeeding-supportive society, and better breastfeeding knowledge and experiences (a previous successful breastfeeding experience ≥6 months and early initiation of breastfeeding). Maternal age of ≥40 years, caesarean delivery, and infant disease history were associated with non-exclusive breastfeeding. CONCLUSIONS: The exclusive breastfeeding rate is still very low in China. Multidimensional barriers contribute to this situation. A comprehensive intervention framework is needed to increase optimal breastfeeding and achieve substantial public health gains.


Assuntos
Aleitamento Materno , Mães , Adulto , China , Estudos Transversais , Emprego , Feminino , Humanos , Lactente , Gravidez
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