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1.
Scand J Med Sci Sports ; 34(6): e14669, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39031563

RESUMO

OBJECTIVES: The aim of this study was to analyze the temporal trends in cardiorespiratory fitness (CRF) and body mass index (BMI) among children and adolescents from 1985 to 2019. METHODS: A total of 1 840 212 children and adolescents aged 7-18 years (921 223 boys) were tested for CRF from 1985 to 2019. CRF was tested by 50-m × 8 shuttle run for boys and girls aged 7-12 years, 1000-m run for boys aged 13-18 years, and 800-m run for girls aged 13-18 years. Trends in BMI from 2000 to 2019 were also investigated. RESULTS: Cardiorespiratory fitness decreased during the entire 34 years among children and adolescents in all sex and age categories, and the most rapid decline occurred from 1995 to 2005. Some positive trends in CRF were observed among adolescents aged 13-15 years from 2005 to 2019 and among girls aged 16-18 years from 2014 to 2019. The variation in the CRF distribution was not uniform, with Z-scores for participants with high CRF levels changing little or increasing (CRF stabilized or improved) and Z-scores for participants with low CRF levels continuing to decrease (CRF decreased). BMI increased over time for boys and girls in all age categories, with an acceleration of the increase for adolescents in recent years. CONCLUSIONS: This study revealed that the overall CRF levels of Chinese children and adolescents decreased over three decades but stabilized or improved in recent years. BMI continued to increase. Our findings are important for the focus on future domestic physical fitness and public health.


Assuntos
Índice de Massa Corporal , Aptidão Cardiorrespiratória , Humanos , Adolescente , Feminino , Masculino , Criança , China , Teste de Esforço , População do Leste Asiático
3.
Sci Total Environ ; 942: 173771, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-38851351

RESUMO

The impact of microplastics and their additives on soil nutrient cycling, particularly through microbial mechanisms, remains underexplored. This study investigated the effects of polyethylene microplastics, polyethylene resin, and plastic additives on soil nitrogen content, physicochemical properties, nitrogen cycling functional genes, microbial composition, and nitrogen transformation rates. Results showed that all amendments increased total nitrogen but decreased dissolved total nitrogen. Polyethylene microplastics and additives increased dissolved organic nitrogen, while polyethylene resin reduced it and exhibited higher microbial biomass. Amendments reduced or did not change inorganic nitrogen levels, with additives showing the lowest values. Polyethylene resin favored microbial nitrogen immobilization, while additives were more inhibitory. Amendment type and content significantly interacted with nitrogen cycling genes and microbial composition. Distinct functional microbial biomarkers and network structures were identified for different amendments. Polyethylene microplastics had higher gross ammonification, nitrification, and immobilization rates, followed by polyethylene resin and additives. Nitrogen transformation was driven by multiple functional genes, with Proteobacteria playing a significant role. Soil physicochemical properties affected nitrogen content through transformation rates, with C/N ratio having an indirect effect and water holding capacity directly impacting it. In summary, plastic additives, compared to polyethylene microplastics and resin, are less conducive to nitrogen degradation and microbial immobilization, exert significant effects on microbial community structure, inhibit transformation rates, and ultimately impact nitrogen cycling.


Assuntos
Microplásticos , Ciclo do Nitrogênio , Nitrogênio , Polietileno , Microbiologia do Solo , Poluentes do Solo , Solo , Solo/química , Interações Microbianas
4.
Adv Sci (Weinh) ; : e2401423, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884169

RESUMO

Effectively neutralizing inflammatory cytokines is crucial for managing a variety of inflammatory disorders. Current techniques that target only a subset of cytokines often fall short due to the intricate nature of redundant and compensatory cytokine networks. A promising solution to this challenge is using cell membrane-coated nanoparticles (CNPs). These nanoparticles replicate the complex interactions between cells and cytokines observed in disease pathology, providing a potential avenue for multiplex cytokine scavenging. While the development of CNPs using experimental animal models has shown great promise, their effectiveness in scavenging multiple cytokines in human diseases has yet to be demonstrated. To bridge this gap, this study selected macrophage membrane-coated CNPs (MФ-CNPs) and assessed their ability to scavenge inflammatory cytokines in serum samples from patients with COVID-19, sepsis, acute pancreatitis, or type-1 diabetes, along with synovial fluid samples from patients with rheumatoid arthritis. The results show that MФ-CNPs effectively scavenge critical inflammatory cytokines, including interleukin (IL)-6, IL-8, interferon (IFN)-γ, and tumor necrosis factor (TNF)-α, in a dose-dependent manner. Overall, this study demonstrates MФ-CNPs as a multiplex cytokine scavenging formulation with promising applications in clinical settings to treat a range of inflammatory disorders.

6.
Tree Physiol ; 44(4)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38498333

RESUMO

Although Taxodium hybrid 'Zhongshanshan' 406 (Taxodium mucronatum Tenore × Taxodium distichum; Taxodium 406) is an extremely flooding-tolerant woody plant, the physiological and molecular mechanisms underlying acclimation of its roots to long-term flooding remain largely unknown. Thus, we exposed saplings of Taxodium 406 to either non-flooding (control) or flooding for 2 months. Flooding resulted in reduced root biomass, which is in line with lower concentrations of citrate, α-ketoglutaric acid, fumaric acid, malic acid and adenosine triphosphate (ATP) in Taxodium 406 roots. Flooding led to elevated activities of pyruvate decarboxylase, alcohol dehydrogenase and lactate dehydrogenase, which is consistent with higher lactate concentration in the roots of Taxodium 406. Flooding brought about stimulated activities of superoxide dismutase and catalase and elevated reduced glutathione (GSH) concentration and GSH/oxidized glutathione, which is in agreement with reduced concentrations of O2- and H2O2 in Taxodium 406 roots. The levels of starch, soluble protein, indole-3-acetic acid, gibberellin A4 and jasmonate were decreased, whereas the concentrations of glucose, total non-structural carbohydrates, most amino acids and 1-aminocyclopropane-1-carboxylate (ACC) were improved in the roots of flooding-treated Taxodium 406. Underlying these changes in growth and physiological characteristics, 12,420 mRNAs and 42 miRNAs were significantly differentially expressed, and 886 miRNA-mRNA pairs were identified in the roots of flooding-exposed Taxodium 406. For instance, 1-aminocyclopropane-1-carboxylate synthase 8 (ACS8) was a target of Th-miR162-3p and 1-aminocyclopropane-1-carboxylate oxidase 4 (ACO4) was a target of Th-miR166i, and the downregulation of Th-miR162-3p and Th-miR166i results in the upregulation of ACS8 and ACO4, probably bringing about higher ACC content in flooding-treated roots. Overall, these results indicate that differentially expressed mRNA and miRNAs are involved in regulating tricarboxylic acid cycle, ATP production, fermentation, and metabolism of carbohydrates, amino acids and phytohormones, as well as reactive oxygen species detoxification of Taxodium 406 roots. These processes play pivotal roles in acclimation to flooding stress. These results will improve our understanding of the molecular and physiological bases underlying woody plant flooding acclimation and provide valuable insights into breeding-flooding tolerant trees.


Assuntos
MicroRNAs , Taxodium , Transcriptoma , Taxodium/genética , Peróxido de Hidrogênio/metabolismo , Aclimatação , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Carboidratos , Trifosfato de Adenosina/metabolismo , Aminoácidos/metabolismo
7.
Neurobiol Dis ; 193: 106461, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38437992

RESUMO

Alzheimer's disease (AD) is a prevalent neurodegenerative disorder with pathological features of ß-amyloid (Aß) and hyperphosphorylated tau protein accumulation in the brain, often accompanied by cognitive decline. So far, our understanding of the extent and role of adaptive immune responses in AD has been quite limited. T cells, as essential members of the adaptive immune system, exhibit quantitative and functional abnormalities in the brains of AD patients. Dysfunction of the blood-brain barrier (BBB) in AD is considered one of the factors leading to T cell infiltration. Moreover, the degree of neuronal loss in AD is correlated with the quantity of T cells. We first describe the differentiation and subset functions of peripheral T cells in AD patients and provide an overview of the key findings related to BBB dysfunction and how T cells infiltrate the brain parenchyma through the BBB. Furthermore, we emphasize the risk factors associated with AD, including Aß, Tau protein, microglial cells, apolipoprotein E (ApoE), and neuroinflammation. We discuss their regulation of T cell activation and proliferation, as well as the connection between T cells, neurodegeneration, and cognitive decline. Understanding the innate immune response is crucial for providing comprehensive personalized therapeutic strategies for AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/metabolismo , Proteínas tau/metabolismo , Linfócitos T/metabolismo , Encéfalo/metabolismo , Peptídeos beta-Amiloides/metabolismo , Disfunção Cognitiva/patologia
8.
Am J Hum Biol ; 36(1): e23988, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38214463

RESUMO

OBJECTIVES: To examine the secular trends and urban-rural disparities in height of Chinese adolescents aged 18 years from 1985 to 2019. METHODS: Data were extracted from the Chinese National Surveys on Students' Constitution and Health from 1985 to 2019, and the heights of a total of 76 554 boys and 75 908 girls aged 18 years were measured. The Mann-Kendall trend test was used to analyze the secular trends in height. Changes in different periods and urban-rural disparities were tested by z-tests and calculating the ratios of the coefficient of variation (CV) of height. RESULTS: The height of Chinese boys and girls aged 18 years increased from 168.21 and 157.10 cm in 1985 to 172.15 cm and 160.11 cm in 2019, respectively, with a larger increase in rural areas. The secular trends in height were the largest for boys from 1995 to 2005 and for girls from 2014 to 2019, and the same results were observed in urban and rural areas. The urban-rural disparities for boys and girls decreased by 1.79 and 0.91 cm, respectively, with significant decreases for boys in all regions and for girls in the eastern region. The overall CVs of height increased by 0.13% and 0.25% for boys and girls, respectively, with the largest increase among rural girls. CONCLUSIONS: The height of Chinese adolescents aged 18 years continued to increase between 1985 and 2019. The urban-rural disparities narrowed, and inequalities within rural areas for girls increased.


Assuntos
Estatura , População Rural , População Urbana , Adolescente , Feminino , Humanos , Masculino , China , Estudantes
9.
J Contam Hydrol ; 260: 104263, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38091660

RESUMO

In this paper, the barrier mechanism of silico-alkaline sol-modified bentonite as cutoff wall materials for lead ions in lead­zinc tailings ponds was investigated. Mechanical property tests, adsorption capacity tests, and permeability tests were conducted to assess the performance of the materials. The results indicated that the addition of silico-alkaline sol at a proportion of 20% by weight of bentonite improved the mechanical strength, anti-seepage ability, and adsorption capacity of the materials towards lead ions. The modification process of bentonite using silico-alkaline sol was confirmed through XED analysis. It was observed that silico-alkaline sol particles adsorbed onto the end face of montmorillonite crystal layer, altering its charge properties. This modification enhanced the adsorption capacity of bentonite towards metal cations. The interaction between the cutoff walls and lead ions was primarily governed by ion exchange. Through the utilization of CT and the finite element method (FEM), demonstrated the exiguity of connected flow lines in the vertical direction within the cutoff walls. Furthermore, column tests revealed that lead ions permeating through the cutoff walls gradually transformed into residuals and were immobilized within the wall. Visual Modflow analysis confirmed the effective application of the cutoff wall in remediating contaminated sites and the potential for practical implementation.


Assuntos
Bentonita , Zinco , Bentonita/química , Lagoas , Poluição Ambiental , Adsorção , Íons , Concentração de Íons de Hidrogênio
10.
JAMA Neurol ; 81(1): 10-18, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37955917

RESUMO

Importance: Suicide risk may be increased in patients with Parkinson disease (PD), a common neurodegenerative condition. Mood disorders, especially depression, are prevalent in patients with PD who report suicidality. Objective: To address inconsistent results from studies of suicidal ideation and behavior in patients with PD. Data Sources: The study team searched MEDLINE and Embase from inception to June 14, 2023, and further screened the bibliographies of relevant studies to ensure a comprehensive search. Study Selection: Original studies, published in English, discussing either suicidal ideation, behavior, or both in adults with PD were included. Accepted study designs included cross-sectional, case-control, and cohort studies. Studies that only included patients with PD after deep brain stimulation were excluded. Data Extraction and Synthesis: This meta-analysis was conducted in line with the PRISMA guidelines. Two authors reviewed each study and extracted the data independently, with discrepancies referred to a third independent author. Main Outcomes and Measures: Outcomes included the prevalence of suicidal ideation and behavior, measured as proportions, and the risk of suicidal behavior in patients with PD relative to controls, measured in both odds ratio (OR) and hazards ratio (HR). Results: A total of 28 studies comprising 505 950 PD patients were included in the final analysis. The prevalence of suicidal ideation was evaluated in 14 studies (22.2%; 95% CI, 14.6-32.3) and suicidal behavior in 21 studies (1.25%; 95% CI, 0.64-2.41). Excluding 4 outliers, prevalence of suicidal behavior was significantly higher in prospective studies (1.75%; 95% CI, 1.03-2.95) than retrospective studies (0.50%; 95% CI, 0.24-1.01). Excluding 1 outlier, OR of suicidal behavior was pooled across 10 studies and significant (OR, 2.15; 95% CI, 1.22-3.78; P = .01). HR of suicidal behavior was assessed in 9 studies (HR, 1.73; 95% CI, 1.40-2.14; P < .001). Conclusions and Relevance: This meta-analysis involving more than 500 000 patients with PD found 22.2% and 1.25% of patients with PD to have suicidal ideation and behavior, respectively. Patients with PD had 2 times the risk of suicidal behavior than controls. Early recognition and management of suicidality in PD can help reduce mortality.


Assuntos
Doença de Parkinson , Ideação Suicida , Adulto , Humanos , Tentativa de Suicídio , Estudos Retrospectivos , Doença de Parkinson/epidemiologia , Estudos Prospectivos , Estudos Transversais
11.
Langmuir ; 39(49): 18113-18123, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38015157

RESUMO

Currently, the mechanical performance of carbon fibers (CFs) has yet to fully realize its theoretical potential. This is predominantly attributed to the significant constraints posed by surface defects, greatly impeding the widespread application of carbon fibers. In order to address this issue, we employed a sonochemical-induced approach in this study to achieve in situ growth of nanoscale zeolitic imidazolate framework-8 (ZIF-8) at the surface defects of carbon fibers. After high-temperature treatment, the structure of ZIF-8 decomposed into ZnO and inorganic carbon, reinforcing the carbon fiber structure from both flexible and rigid aspects. Our research indicates that when the temperature reaches 500 °C, a substantial portion of ZIF-8 undergoes thermal decomposition, giving rise to zinc oxide and inorganic carbon. The flexible inorganic carbon and rigid ZnO form a meshlike structure, which welds to the surface defects of carbon fibers, resulting in strong interactions and contributing to the delay of fiber fracture. Compared to unmodified carbon fibers, the mechanical performance increased by approximately 15.86%. Based on the aforementioned analysis, this method can be considered a direct and effective approach for reinforcing carbon fiber structures, presenting a novel approach for the precise elimination of surface defects on carbon fibers.

12.
Biomaterials ; 302: 122330, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37742508

RESUMO

Botulinum toxin (BoNT) is a potent neurotoxin that poses a significant threat as a biowarfare weapon and a potential bioterrorist tool. Currently, there is a lack of effective countermeasures to combat BoNT intoxication in the event of a biological attack. Here, we report on a novel solution by combining cell metabolic engineering with cell membrane coating nanotechnology, resulting in the development of glycan-modified cellular nanosponges that serve as a biomimetic and broad-spectrum BoNT detoxification strategy. Specifically, we increase the expression levels of gangliosides on THP-1 cells through metabolic engineering, and then collect the modified THP-1 cell membrane and coat it onto synthetic polymeric cores, creating cellular nanosponges that closely mimic host cells. Our findings demonstrate that higher levels of gangliosides on the cellular nanosponges result in greater binding capacities with BoNT. The glycan-modified cellular nanosponges exhibit superior efficacy in neutralizing BoNT cytotoxicity in vitro when compared to their unmodified counterparts. In a mouse model of BoNT intoxication, the glycan-modified cellular nanosponges show more pronounced survival benefits when administered both as a treatment and a preventative regimen. These results highlight the potential of cellular nanosponges, especially when modified with glycans, as a promising countermeasure platform against BoNT and related clostridial toxins.


Assuntos
Toxinas Botulínicas , Camundongos , Animais , Membrana Celular/metabolismo , Gangliosídeos/metabolismo , Polissacarídeos
13.
Small ; 19(52): e2305551, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37635117

RESUMO

Nanoparticles coated with natural cell membranes have emerged as a promising class of biomimetic nanomedicine with significant clinical potential. Among them, macrophage membrane-coated nanoparticles hold particular appeal due to their versatility in drug delivery and biological neutralization applications. This study employs a genetic engineering approach to enhance their in vivo residence times, aiming to further improve their performance. Specifically, macrophages are engineered to express proline-alanine-serine (PAS) peptide chains, which provide additional protection against opsonization and phagocytosis. The resulting modified nanoparticles demonstrate prolonged residence times when administered intravenously or introduced intratracheally, surpassing those coated with the wild-type membrane. The longer residence times also contribute to enhanced nanoparticle efficacy in inhibiting inflammatory cytokines in mouse models of lipopolysaccharide-induced lung injury and sublethal endotoxemia, respectively. This study underscores the effectiveness of genetic modification in extending the in vivo residence times of macrophage membrane-coated nanoparticles. This approach can be readily extended to modify other cell membrane-coated nanoparticles toward more favorable biomedical applications.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas , Camundongos , Animais , Sistemas de Liberação de Medicamentos/métodos , Macrófagos/metabolismo , Membrana Celular/metabolismo , Citoplasma
14.
Planta ; 258(3): 66, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37592053

RESUMO

MAIN CONCLUSION: Taxodium 703 leaves activate fermentation, amino acids metabolism and ROS detoxification, and reduce TCA cycle and ABA biosynthesis in acclimation to prolonged partial submergence stress. Taxodium hybrid 'Zhongshanshan 703' (T. mucronatum × T. distichum; Taxodium 703) is a highly flooding-tolerant woody plant. To investigate the physiological and transcriptional regulatory mechanisms underlying its leaves in acclimation to long-term flooding, we exposed cuttings of Taxodium 703 to either non-flooding (control) or partial submergence for 2 months. The leaf tissues above (AL) and below (BL) flooding-water were separately harvested. Partial submergence decreased concentrations of chlorophyll (a + b) and dehydroascorbate (DHA) and lactate dehydrogenase (LDH) activity in AL, and reduced biomass, concentrations of succinic acid, fumaric acid and malic acid, and transcript levels of genes involved in tricarboxylic acid (TCA) cycle in BL. Under partial submergence, concentrations of starch, malondialdehyde and abscisic acid (ABA) decreased, and also mRNA levels of nine-cis-epoxycarotenoid dioxygenases that are involved in ABA biosynthesis in AL and BL of Taxodium 703. Partial submergence increased O2- content in AL, and improved concentrations of pyruvate and soluble sugars and activities of LDH and peroxidase in BL. In addition, partial submergence increased concentrations of ethanol, lactate, alanine, γ-aminobutyric acid, total amino acids and ascorbic acid (ASA), and ASA/DHA, activities of alcohol dehydrogenases (ADH) and ascorbate peroxidase, as well as transcript levels of ADH1A, ADH1B and genes involved in alanine biosynthesis and starch degradation in AL and BL of Taxodium 703. Overall, these results suggest that Taxodium 703 leaves activate fermentation, amino acids metabolism and reactive oxygen species detoxification, and maintain a steady supply of sugars, and reduce TCA cycle and ABA biosynthesis in acclimation to prolonged partial submergence stress.


Assuntos
Taxodium , Aclimatação , Fermentação , Alanina , Aminoácidos , Ácido Ascórbico
15.
Am J Hum Biol ; 35(12): e23964, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37466179

RESUMO

OBJECTIVES: To understand the distribution and secular trends of Chinese adult boys and girls and investigate their spatial network effects and determinants of spatial network effects. METHODS: Our study extracted data of 18-year-old boys and 17-year-old girls in China from the national students fitness and health survey reports in 1985, 2000, 2010, and 2019. A total of 89 839 participants were selected. The growth range and growth rate in each period were calculated. A neighborhood relationship network was created to share the common boundary. RESULTS: During the period 1985-2019, the average height of Chinese 18-year-old boys increased from 168.19 to 172.14 cm, and that of 17-year-old girls increased from 156.97 to 160.17 cm (all p trend <.05). Both boys and girls showed significant correlations in first- and second-level neighbors (all p < .05) with the most significant correlations in first-level neighbors (all p < .001). But there were no significant correlations in third-level neighbors. Height of girls and boys in each region was correlated with gross domestic product (GDP) per capita, urbanization rate, population density, longitude, and latitude. After controlling for factors with significance, only the initial regional height of girls in 2000 was positively correlated with first level neighborhood (p < .05). CONCLUSION: Since 1985, the heights of Chinese boys aged 18 and girls aged 17 have been increasing and the increases accelerated. Height is related to nearer neighbors. After controlling GDP per capita, urbanization rate, population density, longitude and latitude, the correlations has almost disappeared.


Assuntos
Estatura , População do Leste Asiático , Adolescente , Feminino , Humanos , Masculino , China/epidemiologia , Inquéritos Epidemiológicos , Estudantes
16.
Artigo em Inglês | MEDLINE | ID: mdl-37319005

RESUMO

A novel Gram-stain-negative, catalase- and oxidase-positive, facultatively anaerobic, and rod-shaped motile bacterial strain, designated as YLB-11T, was isolated from seahorse intestine. The 16S rRNA gene sequencing analysis showed that YLB-11T was most closely related Vibrio mytili LMG 19157T (98.9 % nucleotide sequence identity). Phylogenetic analysis placed strain YLB-11T within the genus Vibrio. The major cellular fatty acids were summed feature 3 (C16: 1 ω6c/C16 : 1 ω7c, 36.4 %), C16 : 0 (19.1 %) and summed feature 8 (C18:1 ω6c/C18:1 ω7c, 12.3 %). The DNA G+C content of YLB-11T was 44.7 mol %. The in silico DNA-DNA hybridization and average nucleotide identity values for whole-genome sequence comparisons between YLB-11T and related species were clearly below the thresholds used for the delineation of a novel species. Therefore, YLB-11T is considered to represent novel species of the genus Vibrio, for which the name Vibrio intestinalis sp. nov. is proposed. The type strain is YLB-11T (=MCCC 1A17441T=KCTC 72604T).


Assuntos
Ácidos Graxos , Vibrio , Ácidos Graxos/química , Fosfolipídeos , Análise de Sequência de DNA , Filogenia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Composição de Bases , Técnicas de Tipagem Bacteriana
17.
J Hazard Mater ; 458: 131857, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37354715

RESUMO

Microplastics (MPs) have emerged as pollutants of growing concern due to their potential threat to soil ecosystems. While some studies have investigated the effects of MPs on soil nitrogen content, the underlying physicochemical and microbial driving mechanisms still need to be explored. In this study, a six-month incubation experiment was conducted with varying polyethylene MP addition rates: CK (0%, mass ratio), MP0.5 (0.5%), MP1 (1%), MP2 (2%), MP4 (4%), and MP8 (8%). The experiment aimed to examine the effects of MPs on soil nitrogen content, physicochemical properties, nitrogen cycling-related genes, microorganisms, and gross nitrogen transformation rates. The results revealed no significant changes in soil total nitrogen and dissolved total nitrogen. However, dissolved organic nitrogen significantly decreased by 16.00-54.60% following MP addition, while ammonium (NH4+-N, 45.71-271.43%) and nitrate (NO3--N, 43.15-209.54%) nitrogen and microbial biomass nitrogen (46.02-123.70%) significantly increased. Soil pH, bulk density, and soil porosity decreased after MP addition, while soil carbon contents, water-stable macroaggregates, and redox potential increased. The soil microbial community structure changed significantly, and microbial diversity increased under MP treatment. MP addition significantly altered the abundance of soil nitrogen cycling functional genes. The relative abundance of nitrogen fixation and denitrification genes decreased with increasing MP addition rates, while organic degradation and synthesis genes increased. The soil nitrogen cycling functional microbial composition shifted dramatically with increased MP addition. Networks with high addition rates (MP2 +MP4 +MP8) exhibited more total nodes, total links, negative links, node degrees, and modules but shorter average path distances and lower modularity than those with low addition rates (CK +MP0.5 +MP1), reflecting increased network complexity induced by MPs. The gross ammonification rate, NH4+-N consumption and immobilization rates, and NO3--N immobilization rate increased, while the gross nitrification rate and net nitrification rate exhibited an initial increase followed by a decrease with increasing MP addition rates, peaking at MP2. Furthermore, redundancy analysis and structural equation modeling demonstrated that soil physicochemical properties significantly affected soil nitrogen cycling genes and microorganisms, ultimately altering nitrogen content. In conclusion, polyethylene MPs promoted soil nitrogen mineralization and transformation and changed the related functional microorganism community structure, exhibiting a noticeable dose-effect relationship. This study provides deeper insight into the effects of MPs on soil nitrogen cycling.


Assuntos
Microbiota , Nitrogênio , Nitrogênio/metabolismo , Plásticos , Microplásticos , Polietileno , Solo , Microbiologia do Solo
18.
Artigo em Inglês | MEDLINE | ID: mdl-36828801

RESUMO

The rise of antibiotic resistance has caused the prevention and treatment of bacterial infections to be less effective. Therefore, researchers turn to nanomedicine for novel and effective antibacterial therapeutics. The effort resulted in the first-generation antibacterial nanoparticles featuring the ability to improve drug tolerability, circulation half-life, and efficacy. Toward developing the next-generation antibacterial nanoparticles, researchers have integrated design elements that emphasize physical, broad-spectrum, biomimetic, and antivirulence mechanisms. This review highlights four emerging antibacterial nanoparticle designs: inorganic antibacterial nanoparticles, responsive antibacterial nanocarriers, virulence nanoscavengers, and antivirulence nanovaccines. Examples in each design category are selected and reviewed, and their structure-function relationships are discussed. These emerging designs open the door to nontraditional antibacterial nanomedicines that rely on mechano-bactericidal, function-driven, nature-inspired, or virulence-targeting mechanisms to overcome antibiotic resistance for more effective antibacterial therapy. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease.


Assuntos
Infecções Bacterianas , Doenças Transmissíveis , Nanopartículas , Humanos , Infecções Bacterianas/tratamento farmacológico , Nanopartículas/uso terapêutico , Nanomedicina/métodos , Doenças Transmissíveis/tratamento farmacológico , Antibacterianos/uso terapêutico
19.
Front Microbiol ; 13: 1044986, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36504773

RESUMO

Black soldier fly (Hermetia illucens) larvae (BSFL) act as a biological system converting organic waste into protein and fat with great potential application as pet food. To evaluate the feasibility of BSFL as a protein and fat source, 20 healthy beagle dogs were fed three dietary treatments for 65 days, including (1) a basal diet group (CON group), (2) a basal diet that replaced 20% chicken meal with defatted black soldier fly larvae protein group (DBP group), and (3) a basal diet that replaced 8% mixed oil with black soldier fly larvae fat group (BF group). This study demonstrated that the serum biochemical parameters among the three groups were within the normal range. No difference (p > 0.05) was observed in body weight, body condition score, or antioxidant capacity among the three groups. The mean IFN-γ level in the BF group was lower than that in the CON group, but there was no significant difference (p > 0.05). Compared with the CON group, the DBP group had decreasing (p < 0.05) apparent crude protein and organic matter digestibility. Furthermore, the DBP group had decreasing (p < 0.05) fecal propionate, butyrate, total short-chain fatty acids (SCFAs), isobutyrate, isovalerate, and total branched-chain fatty acids (BCFAs) and increased (p < 0.05) fecal pH. Nevertheless, there was no difference (p > 0.05) in SCFAs or BCFAs between the CON and BF groups. The fecal microbiota revealed that Lachnoclostridium, Clostridioides, Blautia, and Enterococcus were significantly enriched in the DBP group, and Terrisporobacter and Ralstonia were significantly enriched in the BF group. The fecal metabolome showed that the DBP group significantly influenced 18 metabolic pathways. Integrating biological and statistical correlation analysis on differential fecal microbiota and metabolites between the CON and DBP groups found that Lachnoclostridium, Clostridioides, and Enterococcus were positively associated with biotin. In addition, Lachnoclostridium, Clostridioides, Blautia, and Enterococcus were positively associated with niacinamide, phenylalanine acid, fumaric acid, and citrulline and negatively associated with cadavrine, putrescine, saccharopine, and butyrate. In all, 20% DBP restrained the apparent CP and OM digestibility, thereby affecting hindgut microbial metabolism. In contrast, 8% BF in the dog diet showed no adverse effects on body condition, apparent nutrient digestibility, fecal microbiota, or metabolic profiles. Our findings are conducive to opening a new avenue for the exploitation of DBP and BF as protein and fat resources in dog food.

20.
Plants (Basel) ; 11(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36559565

RESUMO

Taxodium hybrid Zhongshanshan has been widely planted in the Yangtze River Basin (YRB) for soil and carbon conservation, with quantities over 50 million. The objective of this study was to determine how T. hybrid Zhongshanshan plantations affected soil physicochemical properties and bacterial community structure in the YRB, and to examine the consistency of changes by afforestation. Soils under T. Zhongshanshan plantations across six sites of the YRB were compared with soils of adjacent non-forested sites. Soil physicochemical properties and bacterial community structure were determined to clarify edaphic driving factors and reveal the effects of afforestation on bacteria. The results indicated that most soil attributes manifested improvements, e.g., total nitrogen in Jiangxi and Shanghai; available phosphorus in Hubei, Chongqing and Yunnan, exhibited the potential to maintain or ameliorate soil quality. A decrease in soil bulk density caused by plantation was also observed at the expense of soil macro-aggregates augment. Afforestation of T. Zhongshanshan plantation has habitually improved Shannon diversity and Chao1 richness, of which dominant phyla were Proteobacteria, Acidobacteria, and Actinobacteria, and increased the relative abundance of the phyla Proteobacteria and Nitrospirae, and the classes Flavobacteriia, Acidobacteria_Gp5, and Bacilli. We concluded that T. Zhongshanshan plantation can be employed to facilitate soil nutrient accumulation in the YRB, but that the degree, rate and direction of changes in soil attributes are sites dependent. It is recommended that afforestation of nutrient-depleted and less productive lands in the YRB should utilize this fast-growing species in combination with proper fertilization.

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