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1.
J Chem Phys ; 160(23)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38884398

RESUMO

The rotational spectrum of an acrolein-formaldehyde complex has been characterized using pulsed jet Fourier transform microwave spectroscopy complemented with quantum chemical calculations. One isomer has been observed in pulsed jets, which is stabilized by a dominant O=C⋯O tetrel bond (n → π* interaction) and a secondary C-H⋯O hydrogen bond. Splittings arising from the internal rotation of formaldehyde around its C2v axis were also observed, from which its V2 barrier was evaluated. It seems that when V2 equals or exceeds 4.61 kJ mol-1, no splitting of the spectral lines of the rotational spectrum was observed. The nature of the non-covalent interactions of the target complex is elucidated through natural bond orbital analysis. These findings contribute to a deeper understanding on the non-covalent interactions within the dimeric complex formed by two aldehydes.

2.
Anal Methods ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38855899

RESUMO

Salmonella enterica is a common foodborne pathogen that can cause food poisoning in humans. The organism also infects and causes disease in animals. Rapid and sensitive detection of S. enterica is essential to prevent the spread of this pathogen. Traditional technologies for the extraction and detection of this pathogen from complex food matrices are cumbersome and time-consuming. In this study, we introduced a novel strategy of biphasic assay integrated with an accelerated strand exchange amplification (ASEA) method for efficient detection of S. enterica without culture or other extraction procedures. Food samples are rapidly dried, resulting in a physical fluidic network inside the dried food matrix, which allows polymerases and primers to access the target DNA and initiate ASEA. The dried food matrix is defined as the solid phase, while amplification products are enriched in the supernatant (liquid phase) and generate fluorescence signals. The analytical performances demonstrated that this strategy was able to specifically identify S. enterica and did not show any cross-reaction with other common foodborne pathogens. For artificially spiked food samples, the strategy can detect 5.0 × 101 CFU mL-1S. enterica in milk, 1.0 × 102 CFU g-1 in duck, scallop or lettuce, and 1.0 × 103 CFU g-1 in either oyster or cucumber samples without pre-enrichment of the target pathogen. We further validated the strategy using 82 real food samples, and this strategy showed 92% sensitivity. The entire detection process can be finished, sample-to-answer, within 50 min, dramatically decreasing the detection time. Therefore, we believe that the proposed method enables rapid and sensitive detection of S. enterica and holds great promise for the food safety industry.

3.
Sensors (Basel) ; 24(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38894276

RESUMO

Malicious social bots pose a serious threat to social network security by spreading false information and guiding bad opinions in social networks. The singularity and scarcity of single organization data and the high cost of labeling social bots have given rise to the construction of federated models that combine federated learning with social bot detection. In this paper, we first combine the federated learning framework with the Relational Graph Convolutional Neural Network (RGCN) model to achieve federated social bot detection. A class-level cross entropy loss function is applied in the local model training to mitigate the effects of the class imbalance problem in local data. To address the data heterogeneity issue from multiple participants, we optimize the classical federated learning algorithm by applying knowledge distillation methods. Specifically, we adjust the client-side and server-side models separately: training a global generator to generate pseudo-samples based on the local data distribution knowledge to correct the optimization direction of client-side classification models, and integrating client-side classification models' knowledge on the server side to guide the training of the global classification model. We conduct extensive experiments on widely used datasets, and the results demonstrate the effectiveness of our approach in social bot detection in heterogeneous data scenarios. Compared to baseline methods, our approach achieves a nearly 3-10% improvement in detection accuracy when the data heterogeneity is larger. Additionally, our method achieves the specified accuracy with minimal communication rounds.

4.
Nurse Educ Pract ; 77: 103974, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38728791

RESUMO

AIM: To explore the scope and form of prescriptions for blood and hematopoietic drugs that future advanced practice nurses (APNs) in the Department of Haematology and to establish a medicine prescription training content in China. BACKGROUND: Because the increasing number of doctors cannot meet the increasing demand for medical care with the population growth, many countries have begun to explore the medical team structure and practice areas, among which nurse prescribing rights have been the most effective. However, China's higher nursing education system still lacks education and training on nurse prescription. DESIGN: On the basis of literature research and semi-structured interviews, a set of nursing prescription content, education, training and practice system suitable for Chinese nurses was jointly created. METHODS: Two rounds of expert consultation between 23 haematology nursing experts and clinical experts determined the training content of blood system drugs and medicine prescriptions. Additionally, on the basis of the 23 experts,13 experts engaged in clinical and education, teaching and training experts were involved. Two rounds of expert consultation with 36 experts identified a general clinical practice training program for advanced practice nurses in China. RESULTS: Regarding contents and forms of hematopoietic drugs, the study concluded that advanced practice nurses in haematology department can prescribe anti-anemia drugs, anti-coagulant drugs and anti-thrombotic drugs in 2 categories and 16 drugs. Of these, four kinds of drugs should be prescribed in the form of protocol prescription. One kind of drug should be prescribed in the form of extended prescription and 11 drugs should be prescribed in the form of independent/extended or agreed/extended prescription. Regarding training content, the study obtained the training content of nurses' medicine prescriptions in eight clinical circumstances and the medicine prescription training content for common diseases of the blood system. The required specifications and the medicine prescription decision skills of nurses were sorted out according to different prescription types. CONCLUSIONS: The degrees of expert authority were both higher in consultations. Moreover, the results after consultation were reliable. It was recommended that haematology APNs could prescribe anti-anaemic drugs and anti-coagulation and anti-thrombotic drugs. Furthermore, most drugs should be prescribed in the form of independent/extended or agreed/extended prescriptions. The establishment of a medicine prescription training content for haematology APNs is expected to provide a reference for clinical practice education and training for drug prescriptive authority applicants for blood and hematopoietic system nurses in China.


Assuntos
Prática Avançada de Enfermagem , Técnica Delphi , Hematologia , Humanos , China , Prática Avançada de Enfermagem/educação , Hematologia/educação , Prescrições de Medicamentos/enfermagem , Feminino , Adulto , Masculino , Inquéritos e Questionários
5.
Opt Express ; 32(7): 11377-11386, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38570986

RESUMO

This work reports a high-performance InGaN-based red-emitting LED with a strain-release interlayer (SRI) consisting of an InGaN stress-release layer (SRL) and an AlN dislocation confinement layer (DCL) in unintentionally doped GaN (u-GaN). The SRL introduces a tensile strain which could decrease the in-plane compressive stress of the u-GaN layer, while the DCL could reduce the dislocation density and thus improve the crystal quality of the u-GaN layer. Consequently, a high-efficiency InGaN-based red-emitting LED with a peak wavelength of 651 nm and an external quantum efficiency of 6.04% is realized. In addition, the room-temperature photoluminescence (PL) mapping emission wavelength is uniform across a 4-inch wafer with a standard deviation of 3.3 nm. Therefore, the proposed SRI offers good potential for mass-producing high-performance and long-wavelength InGaN-based red-emitting LEDs.

6.
Antiviral Res ; 225: 105875, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552910

RESUMO

The DEAD-box (DDX) family comprises RNA helicases characterized by the conserved sequence D(Asp)-E(Glu)-A(Ala)-D(Asp), participating in various RNA metabolism processes. Some DDX family members have been identified for their crucial roles in viral infections. In this study, RNAi library screening of the DDX family unveiled the antiviral activity of DDX20. Knockdown of DDX20 enhanced the replication of viruses such as vesicular stomatitis virus (VSV) and herpes simplex virus type I (HSV-1), while overexpression of DDX20 significantly diminished the replication level of these viruses. Mechanistically, DDX20 elevated the phosphorylation level of IRF3 induced by external stimuli by facilitating the interaction between TBK1 and IRF3, thereby promoting the expression of IFN-ß. The increased IFN-ß production, in turn, upregulated the expression of interferon-stimulated genes (ISGs), including Cig5 and IFIT1, thereby exerting the antiviral effect. Finally, in an in vivo infection study, Ddx20 gene-deficient mice exhibited increased susceptibility to viral infection. This study provides new evidence that DDX20 positively modulates the interferon pathway and restricts viral infection.


Assuntos
Herpesvirus Humano 1 , Interferon Tipo I , Viroses , Animais , Camundongos , Interferons/metabolismo , Interferon beta/metabolismo , Transdução de Sinais , Diclorodifenil Dicloroetileno/metabolismo , Replicação Viral , Herpesvirus Humano 1/genética , Antivirais/metabolismo , Imunidade Inata , Fator Regulador 3 de Interferon/metabolismo , Interferon Tipo I/metabolismo , Proteína DEAD-box 20/metabolismo
7.
Mikrochim Acta ; 191(4): 220, 2024 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532188

RESUMO

Recently, covalent organic frameworks have gained popularity in sample pretreatment. However, the application of covalent organic frameworks in the enrichment of hydrophilic compounds remains a challenge. Thus, a functionalized magnetic covalent organic framework equipped with amino groups was constructed using a bottom-up functionalization strategy. Considering the advantages of this novel adsorbent such as high porosity, large adsorption capacity, and hydrophilic surface, a sensitive magnetic solid-phase extraction coupled with high-performance liquid chromatography-tandem mass spectrometry method was established for the effective determination of neonicotinoids. This method exhibited good linearities with correlation coefficients ranging from 0.9983 to 0.9995, low detection limits in the range 0.003-0.009 ng g-1 and 0.001-0.013 ng mL-1, and limits of quantification in the range 0.010-0.031 ng g-1 and 0.004-0.044 ng mL-1. Furthermore, satisfactory repeatability with relative standard deviations ≤ 6.7% and spiked recoveries between 82.3 and 99.8% were obtained. This work not only provided a promising adsorbent for the sensitive determination of trace-level neonicotinoids but also represented a unique insight for effective enrichment of super hydrophilic hazards.


Assuntos
Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Neonicotinoides , Magnetismo , Cromatografia Líquida de Alta Pressão , Fenômenos Magnéticos
8.
Front Cardiovasc Med ; 11: 1344975, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38414922

RESUMO

Primary pericardial angiosarcoma is a rare malignancy of the pericardium with variable clinical features and imaging characteristics. Herein, we report a case of histopathologically confirmed pericardial angiosarcoma in a 66-year-old man. The patient developed cardiac tamponade in a short time period. The transthoracic echocardiography showed the presence of multiple irregular echodensities, heterogeneous in echogenicity, encasing the apex of both ventricles in the pericardial space, initially misinterpreted as pericardial effusion. The patient died of cardiogenic shock despite undergoing a surgical pericardiectomy. Pericardial angiosarcoma can manifest as a mass obliterating the pericardial sac, rather than the typical pericardial effusion observed on echocardiography. Multimodality imaging studies aid in diagnosing primary pericardial angiosarcoma, but the final diagnosis relies on tissue histopathology.

9.
Psychopharmacology (Berl) ; 241(4): 865-874, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38191677

RESUMO

RATIONALE: The precise diagnosis and treatment of cognitive impairment remains a major challenge in the field of schizophrenia (SCZ) research. Synaptic dysfunction and loss are thought to be closely related to the occurrence and development of SCZ and may be involved in cognitive dysfunction. OBJECTIVES: The purpose of this study was to investigate whether neuronal pentraxins (NPTXs) plays a role in the etiology of SCZ and provide evidence of its possible therapeutic value a new target for drug development. METHODS: We recruited 275 participants, of whom 148 were SCZ from psychiatric hospital and 127 healthy control (HC) subjects from communities. Plasma concentrations of NPTXs were measured in HC and SCZ at baseline and after 8 weeks of antipsychotic treatment. The MATRICS Cognitive Consensus Battery was used to evaluate cognitive function. Furthermore, the brain is parcellated into 246 subregions using the Brainnetome atlas, and we extracted regional white matter volumes from magnetic resonance images of the SCZ groups. RESULTS: Plasma NPTX2 levels were significantly lower in SCZ compared with HC subjects, but were significantly raised in SCZ after 8 weeks of antipsychotic treatment compared to baseline. In addition, baseline plasma NPTX2 levels were positively correlated with cognitive performance. CONCLUSIONS: These findings indicate that NPTX2 may reveal novel aspects of disease etiology and act as a promising target for new drug development.


Assuntos
Antipsicóticos , Disfunção Cognitiva , Proteínas do Tecido Nervoso , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico , Antipsicóticos/farmacologia , Antipsicóticos/uso terapêutico , Proteína C-Reativa , Cognição/fisiologia
10.
Food Chem X ; 21: 101123, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38292675

RESUMO

The impact of exogenous limiting amino acids on protein gel formation was investigated to enhance the gelation properties of Landaise goose myofibrillar protein (MP). Amino acid composition and gel properties were analyzed, and homologous protein modeling and molecular docking techniques were used to simulate binding sites. Valine was identified as the first limiting amino acid. The addition of 0.075 % dl-valine proved optimal to enhance the gel strength (59.5 g) and water retention (76.76 %) of MP gels. Hydrophobic interactions and disulfide bonds were found to be the main forces maintaining conformational stability of the MP-dl-valine gels. The propyl group of dl-valine can form hydrophobic interactions with protein, contributing to stable complexes. DL valine could also strengthen chemical bonds and secondary structure, convert free water to immobile water, and improve the microstructure of the gel. Therefore, valine can be utilized as a nutritional and gel enhancer in Landaise goose meat products.

11.
Genetics ; 226(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38169343

RESUMO

Paramutation is a transfer of heritable silencing states between interacting endogenous alleles or between endogenous alleles and homologous transgenes. Prior results demonstrated that paramutation occurs at the P1-rr (red pericarp and red cob) allele of the maize p1 (pericarp color 1) gene when exposed to a transgene containing a 1.2-kb enhancer fragment (P1.2) of P1-rr. The paramutable P1-rr allele undergoes transcriptional silencing resulting in a paramutant light-pigmented P1-rr' state. To define more precisely the sequences required to elicit paramutation, the P1.2 fragment was further subdivided, and the fragments transformed into maize plants and crossed with P1-rr. Analysis of the progeny plants showed that the sequences required for paramutation are located within a ∼600-bp segment of P1.2 and that this segment overlaps with a previously identified enhancer that is present in 4 direct repeats in P1-rr. The paramutagenic segment is transcribed in both the expressed P1-rr and the silenced P1-rr'. Transcription is sensitive to α-amanitin, indicating that RNA polymerase II mediates most of the transcription of this sequence. Although transcription within the paramutagenic sequence was similar in all tested genotypes, small RNAs were more abundant in the silenced P1-rr' epiallele relative to the expressed P1-rr allele. In agreement with prior results indicating the association of RNA-mediated DNA methylation in p1 paramutation, DNA blot analyses detected increased cytosine methylation of the paramutant P1-rr' sequences homologous to the transgenic P1.2 subfragments. Together these results demonstrate that the P1-rr enhancer repeats mediate p1 paramutation.


Assuntos
Metilação de DNA , Zea mays , Zea mays/genética , Mutação , Plantas/genética , RNA , Elementos Facilitadores Genéticos , Alelos , Regulação da Expressão Gênica de Plantas
12.
Biochem Genet ; 62(1): 371-384, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37351719

RESUMO

Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract which is mediated by the inappropriate immune responses. This study was aimed to identify novel diagnostic biomarkers for diagnosis of IBD and explore the relationship between the diagnostic biomarkers and infiltrated immune cells. GSE38713, GSE53306, and GSE75214 downloaded from the Gene Expression Omnibus (GEO) database were split into training and testing sets. Differentially expressed genes (DEGs) were screened using the "limma" package. Gene Ontology (GO) and KEGG pathway enrichment analysis of DEGs were performed by clusterProfiler package. The LASSO regression and support vector machine recursive feature elimination (SVM-RFE) algorithms were conducted to identify novel diagnostic biomarkers. The receiver operating characteristic (ROC) curve was applied to evaluate the diagnostic value of the candidate biomarkers. The relationship of the candidate biomarkers and infiltrating immune cells in IBD were evaluated by CIBERSOTR. Quantitative Real-Time PCR (qRT-PCR) was applied to measure the expression level of the biomarkers in IBD. A total of 289 dysregulated genes were identified as DEGs in IBD. These DEGs were significantly enriched in chemokine signaling pathway and cytokine-cytokine receptor interaction. RHOU was identified as a critical diagnostic gene in IBD, which was confirmed using ROC curve and qRT-PCR assays. Immune cell infiltration analysis showed that RHOU was correlated with macrophages M2, dendritic cells resting, mast cells resting, T cells CD4 memory resting, macrophages M0, and mast cells activated. Our results imply that RHOU may be a potential diagnostic biomarker for IBD.


Assuntos
Doenças Inflamatórias Intestinais , Humanos , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/genética , Aprendizado de Máquina , Biologia Computacional , Citocinas , Biomarcadores
13.
Nutrients ; 15(24)2023 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-38140389

RESUMO

In older men, an age-related decline in testosterone is closely associated with various adverse health outcomes. With the progression of aging, hyperactivation of the local renin-angiotensin system (RAS) and oxidative stress increase in the testis. The regulation of RAS antioxidants may be a target to delay testicular aging and maintain testosterone levels. Exogenous nucleotides (NTs) have anti-aging potential in several systems, but there are no studies of their effects on the reproductive system. In our study, we examined the effects of exogenous NTs on testosterone synthesis and explored possible mechanisms of action. Therefore, senescence-accelerated mouse prone-8 (SAMP8) mice and senescence-accelerated mouse resistant 1 (SAMR1) were used in the experiment, and they were randomly divided into an NTs free group (NTs-F), a normal control group (control), a low-dose NTs group (NTs-L), a middle-dose NTs (NTs-M), a high-dose NTs group (NTs-H) and SAMR1 groups, and the testis of the mice were collected for testing after 9 months of intervention. The results showed that exogenous NTs could increase the testicular organ index in mice during aging, and delayed the age-associated decline in testosterone levels in SAMP8 male mice, possibly by modulating the local RAS antioxidant pathway and reducing oxidative stress to protect the testis. The present study provides new research clues for the development of preventive and therapeutic strategies for related diseases.


Assuntos
Antioxidantes , Testosterona , Humanos , Camundongos , Masculino , Animais , Idoso , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Testosterona/farmacologia , Sistema Renina-Angiotensina , Estresse Oxidativo , Envelhecimento
14.
Mikrochim Acta ; 190(12): 488, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-38015320

RESUMO

A porous magnetic covalent organic framework, Fe3O4@TPBD-TPA (terephthalaldehyde (TPA) , N, N, N', N'-tetrakis(p-aminophenyl)-p-phenylenediamine (TPBD)), was synthesized using the Schiff base reaction under mild reaction conditions. This adsorbent exhibited excellent adsorption performance for aflatoxins. The adsorption capacity of Fe3O4@TPBD-TPA for aflatoxins ranged from 64.4 to 84.4 mg/g. A magnetic solid-phase extraction combined with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method based on Fe3O4@TPBD-TPA was developed for the efficient determination of four types of aflatoxins in food samples (maize, maize oil, peanut, and peanut oil). The determination coefficients (R2) were ≥0.9972. The method exhibited detection limits ranging from 0.01 to 0.06 µg/kg and spiked recoveries of 80.0 to 113.1%. The intra-day and inter-day precision were less than 6.77%, indicating good repeatability. The adsorbent showed promising prospects for the efficient enrichment of trace amounts of aflatoxins in complex food matrices.


Assuntos
Aflatoxinas , Estruturas Metalorgânicas , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem , Fenômenos Magnéticos
15.
Se Pu ; 41(11): 986-994, 2023 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-37968817

RESUMO

Mycotoxins have carcinogenic, mutagenic, hepatotoxic, nephrotoxic, immunotoxic, neurotoxic, and teratogenic properties. Thus, these substances have attracted significant attention because they pose a threat to human health. As research on mycotoxins deepens, new structural analogues of mycotoxins are constantly being discovered. In this study, a method based on high performance liquid chromatography-quadrupole/orbitrap mass spectrometry was established for the simultaneous determination of 22 mycotoxins in milk. A simple, effective, and rapid pretreatment method was optimized by focusing on the solvent type, extractant volume, and extracting salt based on the characteristics of the mycotoxins and sample matrix. The analytes were extracted using 0.5% formic acid acetonitrile solution and added with sodium chloride to separate fats from water. The samples were centrifuged at 8000 r/min (4 ℃) for 5 min using a centrifuge and then concentrated using nitrogen. The dry residue was dissolved with 50% methanol aqueous solution. Twenty-two mycotoxins were separated on a ZORBAX Eclipse Plus C18 chromatographic column (100 mm×2.1 mm, 1.7 µm), and quantitative analysis was performed using the isotope internal standard method. The analytes were determined by liquid chromatography-quadrupole/orbitrap mass spectrometry in positive electrospray ionization mode. Qualitative analyses of the compounds were performed in full mass spectrometry/data-dependent tandem mass spectrometry (MS/dd-MS2) mode. Good linearities in the range of 0.5-100.0 µg/L were observed for the 22 mycotoxins, and the correlation coefficients (R2) were greater than 0.999. The limits of detection (S/N=3) and quantification (S/N=10) ranged from 0.3 to 0.5 µg/kg and from 1.0 to 1.5 µg/kg, respectively. The average recoveries of the 22 mycotoxins at three spiked levels of 1.5, 5.0, and 15 µg/kg were between 84.7% and 100.8%, with relative standard deviations (RSDs) of 1.2%-9.9%. These findings indicate that the method has high sensitivity and accuracy as well as good precision. Finally, the method was applied to the detection and analysis of mycotoxins in 25 actual commercial milk samples. The results revealed that the selected samples were not contaminated with any of the mycotoxins analyzed. Thus, the proposed method is useful as a quick preprocessing and confirmatory method for the simultaneous determination of mycotoxins in milk.


Assuntos
Micotoxinas , Humanos , Animais , Micotoxinas/análise , Leite/química , Cromatografia Líquida , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão
16.
Phys Chem Chem Phys ; 25(45): 31281-31291, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37955344

RESUMO

Rotational spectroscopy represents an invaluable tool for several applications: from the identification of new molecules in interstellar objects to the characterization of van der Waals complexes, but also for the determination of very accurate molecular structures and for conformational analyses. In this work, we used high-resolution rotational spectroscopic techniques in combination with high-level quantum-chemical calculations to address all these aspects for two isomers of cyanofuran, namely 2-furonitrile and 3-furonitrile. In particular, we have recorded and analyzed the rotational spectra of both of them from 6 to 320 GHz; rotational transitions belonging to several singly-substituted isotopologues have been identified as well. The rotational constants derived in this way have been used in conjunction with computed rotation-vibration interaction constants in order to derive a semi-experimental equilibrium structure for both isomers. Moreover, we observed the rotational spectra of four different intermolecular adducts formed by furonitrile and water, whose identification has been supported by a conformational analysis and a theoretical spectroscopic characterization. A semi-experimental determination of the intermolecular parameters has been achieved for all of them and the results have been compared with those obtained for the analogous system formed by benzonitrile and water.

17.
Environ Int ; 182: 108353, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38035535

RESUMO

Micro/nanoplastics in the environment can be ingested by organisms and spread throughout the food chain, ultimately posing a threat to human health. However, the risk of continuous oral exposure in mammals remains unresolved. In this study, we utilized a continuous gavage mouse model to investigate the potential intestinal risks associated with oral exposure to polystyrene micro/nanoplastics (PS-MNPs) with environmentally relevant concentrations. The effects of PS-MNPs with different particle sizes on the gut microbiota, intestinal barrier, and intestinal immune function were evaluated. PS-MNPs can accumulate in the intestine after oral exposure and alter the composition of the gut microbiota. Exposure to PS-MNPs significantly reduced the ratio of Firmicutes to Bacteroidetes as well as the number of potentially beneficial bacteria in the gut, while the number of potentially harmful bacteria significantly increased. The short-chain fatty acids metabolized by gut microbiota were significantly changed by PS-MNPs. Exposure to PS-MNPs disrupts the function of the intestinal barrier and leads to inflammation in the intestines. The levels of secretory immunoglobulin A in the intestine and the differentiation of CD4+ and CD8+ T cells in mesenteric lymph nodes were significantly decreased by PS-MNPs. Moreover, the impact of PS-MNPs on mammalian intestinal health is influenced by the exposure duration and particle size, rather than the concentration. It also suggests that nanoplastics may pose more severe environmental risks.


Assuntos
Microbioma Gastrointestinal , Humanos , Camundongos , Animais , Microplásticos , Disbiose , Linfócitos T CD8-Positivos , Inflamação , Poliestirenos/farmacologia , Mamíferos
18.
Nat Microbiol ; 8(12): 2326-2337, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38030907

RESUMO

Dimethylsulfoxonium propionate (DMSOP) is a recently identified and abundant marine organosulfur compound with roles in oxidative stress protection, global carbon and sulfur cycling and, as shown here, potentially in osmotolerance. Microbial DMSOP cleavage yields dimethyl sulfoxide, a ubiquitous marine metabolite, and acrylate, but the enzymes responsible, and their environmental importance, were unknown. Here we report DMSOP cleavage mechanisms in diverse heterotrophic bacteria, fungi and phototrophic algae not previously known to have this activity, and highlight the unappreciated importance of this process in marine sediment environments. These diverse organisms, including Roseobacter, SAR11 bacteria and Emiliania huxleyi, utilized their dimethylsulfoniopropionate lyase 'Ddd' or 'Alma' enzymes to cleave DMSOP via similar catalytic mechanisms to those for dimethylsulfoniopropionate. Given the annual teragram predictions for DMSOP production and its prevalence in marine sediments, our results highlight that DMSOP cleavage is likely a globally significant process influencing carbon and sulfur fluxes and ecological interactions.


Assuntos
Propionatos , Roseobacter , Sulfetos/metabolismo , Enxofre/metabolismo , Carbono
19.
ACS Omega ; 8(42): 38983-38990, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37901527

RESUMO

In this study, a pilot-scale integrated process was developed, which combined the integrated biological contact oxidation technology (AO) and the improved constructed wetland technology. The results showed significant removal efficiency for both conventional and trace organic pollutants. The average removal efficiencies for COD, NH4+-N, and TP were 78.52, 85.95, and 49.47%, respectively. For trace organic pollutants, triclocarban, triclosan, and sulfadiazine, the removal efficiencies reached 60.14, 57.42, and 84.29%, respectively. The AO stage played a crucial role in removing trace organic pollutants, achieving removal efficiencies of 37.28, 43.44, and 83.82% for triclocarban, triclosan, and sulfadiazine, respectively. Subsequent treatment using improved constructed wetland technology with coal slag + gravel fillers demonstrated the highest removal efficiency, with average efficiencies of 68.66, 63.38, and 81.32% for triclocarban, triclosan, and sulfadiazine, respectively. Correlation analysis revealed positive correlations between temperature, precipitation, and the removal efficiency of COD, NH4+-N, and TP, while negative correlations were observed with the removal efficiency of triclocarban, triclosan, and sulfadiazine. Furthermore, the influent concentrations of triclocarban and triclosan were significantly negatively correlated with the removal efficiency of COD and TP. The presence of triclocarban and triclosan potentially reduced the microbial diversity and hindered sludge sedimentation performance.

20.
Plant Phenomics ; 5: 0091, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37780969

RESUMO

Observable morphological traits are widely employed in plant phenotyping for breeding use, which are often the external phenotypes driven by a chain of functional actions in plants. Identifying and phenotyping inherently functional traits for crop improvement toward high yields or adaptation to harsh environments remains a major challenge. Prediction of whole-plant performance in functional-structural plant models (FSPMs) is driven by plant growth algorithms based on organ scale wrapped up with micro-environments. In particular, the models are flexible for scaling down or up through specific functions at the organ nexus, allowing the prediction of crop system behaviors from the genome to the field. As such, by virtue of FSPMs, model parameters that determine organogenesis, development, biomass production, allocation, and morphogenesis from a molecular to the whole plant level can be profiled systematically and made readily available for phenotyping. FSPMs can provide rich functional traits representing biological regulatory mechanisms at various scales in a dynamic system, e.g., Rubisco carboxylation rate, mesophyll conductance, specific leaf nitrogen, radiation use efficiency, and source-sink ratio apart from morphological traits. High-throughput phenotyping such traits is also discussed, which provides an unprecedented opportunity to evolve FSPMs. This will accelerate the co-evolution of FSPMs and plant phenomics, and thus improving breeding efficiency. To expand the great promise of FSPMs in crop science, FSPMs still need more effort in multiscale, mechanistic, reproductive organ, and root system modeling. In summary, this study demonstrates that FSPMs are invaluable tools in guiding functional trait phenotyping at various scales and can thus provide abundant functional targets for phenotyping toward crop improvement.

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