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1.
Physiol Plant ; 176(2): e14205, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38439620

RESUMO

Rhizobia and arbuscular mycorrhizal fungi (AMF) are symbiotic microorganisms important for plants grown in nutrient-deficient and heavy metal-contaminated soils. However, it remains unclear how plants respond to the coupled stress by heavy metal and nitrogen (N) deficiency under co-inoculation. Here, we investigated the synergistic effect of Mesorhizobium huakuii QD9 and Funneliformis mosseae on the response of black locust (Robinia pseudoacacia L.) grown in sand culture to cadmium (Cd) under N deficiency conditions. The results showed that single inoculation of AMF improved the growth and Cd resistance of black locust, co-inoculation improved the most. Compared to non-inoculated controls, co-inoculation mediated higher biomass and antioxidant enzyme activity, reduced oxidative stress, and promoted nodulation, mycorrhizal colonization, photosynthetic capacity, and N, P, Fe and Mg acquisition when exposed to Cd. This increase was significantly higher under N deficiency compared to N sufficiency. In addition, the uptake of Cd by co-inoculated black locust roots increased, but Cd translocation to the above-ground decreased under both N deficiency and sufficiency. Thus, in the tripartite symbiotic system, not merely metabolic processes but also Cd uptake increased under N deficiency. However, enhanced Cd detoxification in the roots and reduced allocation to the shoot likely prevent Cd toxicity and rather stimulated growth under these conditions.


Assuntos
Micorrizas , Rhizobium , Robinia , Cádmio/toxicidade , Areia , Antioxidantes
2.
Environ Pollut ; 345: 123456, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38307241

RESUMO

The role of rhizobia in alleviating cadmium (Cd) stress in woody legumes is still unclear. Therefore, two types of black locust (Robinia pseudoacacia L.) with high and low Cd accumulation abilities were selected from 11 genotypes in China, and the effects of rhizobium (Mesorhizobium huakuii GP1T11) inoculation on the growth, CO2 and H2O gas exchange parameters, Cd accumulation, and the absorption of mineral elements of the high (SX) and low Cd-accumulator (HB) were compared. The results showed that rhizobium-inoculation significantly increased biomass, shoot Cd contents, Cd accumulation, root-to-shoot translocation factor (TF) and the absorption and accumulation of mineral elements in both SX and HB. Rhizobium-inoculation increased chlorophyll a and carotenoid contents, and the intercellular carbon dioxide concentrations in HB plants. Under Cd exposure, the high-accumulator SX exhibited a significant decrease in photosynthetic CO2 fixation (Pn) and an enhanced accumulation of Cd in leaves, but coped with Cd exposure by increasing chlorophyll synthesis, regulating stomatal aperture (Gs), controlling transpiration (Tr), and increasing the absorption and accumulation of mineral elements. In contrast, the low-accumulator HB was more sensitive to Cd exposure despite preferential accumulation of Cd in roots, with decreased chlorophyll and carotenoid contents, but significantly increased root biomass. Compared to the low-accumulator HB, non-inoculated Cd-exposed SX plants had higher chlorophyll contents, and rhizobium-inoculated Cd-exposed SX plants had higher Pn, Tr, and Gs as well as higher levels of P, K, Fe, Ca, Zn, and Cu. In conclusion, the high- and low-Cd-accumulator exhibited different physiological responses to Cd exposure. Overall, rhizobium-inoculation of black locust promoted the growth and heavy metal absorption, providing an effective strategy for the phytoremediation of heavy metal-contaminated soils by this woody legume.


Assuntos
Metais Pesados , Rhizobium , Robinia , Poluentes do Solo , Cádmio/toxicidade , Robinia/fisiologia , Clorofila A , Dióxido de Carbono/análise , Metais Pesados/farmacologia , Clorofila , Minerais , Carotenoides , Biodegradação Ambiental , Poluentes do Solo/análise
3.
Food Chem X ; 21: 101189, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38357376

RESUMO

Flavor profiles of various Pyrus spp. cultivars exhibit significant variations, yet the underlying flavor-contributing factors remain elusive. In this investigation, a comprehensive approach encompassing metabolomics analysis, volatile fingerprint analysis, and descriptive sensory analysis was employed to elucidate the flavor disparities among Nanguoli, Korla fragrant pear, and Qiuyueli cultivars and uncover potential flavor contributor. The study comprehensively characterized the categories and concentrations of nonvolatile and volatile metabolites, and 925 metabolites were identified. Flavonoids and esters dominated the highest cumulative response, respectively. Utilizing weighted correlation network analysis (WGCNA), seven highly correlated modules were identified, yielding 407 pivotal metabolites. Further correlation analysis of the differential substances provided potential flavor constituents strongly associated with various sensory attributes; taste factors had a certain association with olfactory characteristics. Our findings demonstrated the manifestation of flavor was a result of the synergistic effect of various compounds; evaluation olfactory flavor necessitated a comprehensive consideration of taste substances.

4.
Plant Physiol Biochem ; 207: 108400, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38295526

RESUMO

Lead (Pb) is a widespread highly toxic and persistent environmental pollutant. Plant leaves play a key role in accumulating atmospheric Pb, but its distribution in different cells and subcellular structures and the factors affecting it have been little studied. Here, Tillandsia usneoides, an indicator plant for atmospheric heavy metals, was treated with an aerosol generation device to analyze Pb contents in different cells (three types of cells in leaf surface scales, epidermal cells, mesophyll cells, vascular bundle cells), subcellular structures (cell wall, cell membrane, vacuoles, and organelles) and cell wall components (pectin, hemicellulose 1 and 2, and cellulose). Results show the different cells of T. usneoides leaves play distinct roles in the process of Pb retention. The outermost wing cells are structures that capture external pollutants, while mesophyll cells, as the aggregation site after material transport, ring cells, disc cells, epidermal cells, and vascular cells are material transporters. Pb was only detected in the cell wall and pectin, indicating the cell wall was the dominant subcellular structure for Pb retention, while pectin was the main component affecting Pb retention. FTIR analysis of cell wall components indicated the esterified carboxyl (CO) functional group in pectin may function in absorbing Pb. Pb entered leaf cells mainly in the form of low toxicity and activity to enhance its resistance.


Assuntos
Chumbo , Folhas de Planta , Tillandsia , Poluentes Ambientais , Chumbo/toxicidade , Chumbo/metabolismo , Metais Pesados/metabolismo , Pectinas/metabolismo , Folhas de Planta/metabolismo
5.
Technol Health Care ; 32(1): 143-150, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37248926

RESUMO

BACKGROUND: Pressure injury (PI) is a local injury of the skin and/or soft tissue located at the bone caused by medical or other equipment and is common in long-term bedridden patients. OBJECTIVE: To investigate the clinical effect of Urgotul foam dressing in the treatment of stage 3 ∼ 4 PI and deep tissue PI. METHODS: A total of 38 patients with stage 3 ∼ 4 PI and deep tissue PI admitted to Jinan Central Hospital from January 2016 to December 2018 were selected and randomly divided into a control group (dressing change plus silver ion cream dressing) and an observation group (dressing change plus Urgotul Absorb non-border foam dressing), with 19 cases in each group. After 4 weeks of treatment, the pain intensity during dressing change and the treatment efficacy for PI wounds were compared between the two groups. RESULTS: There were no differences in gender (P= 0.740), age (P= 0.130), single wound area (P= 0.673), consultation department (P= 0.972), stage (P= 0.740), presence of undermining (P= 0.721), deep tissue PI (P= 0.721), and systemic antibiotic therapy (P= 1.000) between the two groups, which were comparable. The treatment effect of the observation group was better than that of the control group (P= 0.003), and the pain score of the observation group was lower than that of the control group (P< 0.001). CONCLUSION: Urgotul Absorb non-border foam dressing has a good effect in the treatment of stage 3 ∼ 4 PI and deep tissue PI and can relieve patients' pain, and is thus worth promoting.


Assuntos
Úlcera por Pressão , Humanos , Úlcera por Pressão/terapia , Bandagens , Resultado do Tratamento , Infecção da Ferida Cirúrgica , Dor
6.
J Hazard Mater ; 465: 133236, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38141298

RESUMO

Biochar could reshape microbial communities, thereby altering methylmercury (MeHg) concentrations in rice rhizosphere and seeds. However, it remains unclear whether and how biochar amendment perturbs microbe-mediated MeHg production in mercury (Hg) contaminated paddy soil. Here, we used pinecone-derived biochar and its six modified biochars to reveal the disturbance. Results showed that selenium- and chitosan-modified biochar significantly reduced MeHg concentrations in the rhizosphere by 85.83% and 63.90%, thereby decreasing MeHg contents in seeds by 86.37% and 75.50%. The two modified bicohars increased the abundance of putative Hg-resistant microorganisms Bacillus, the dominant microbe in rhizosphere. These reductions about MeHg could be facilitated by biochar sensitive microbes such as Oxalobacteraceae and Subgroup_7. Pinecone-derived biochar increased MeHg concentration in rhizosphere but unimpacted MeHg content in seeds was observed. This biochar decreased the abundance in Bacillus but enhanced in putative Hg methylator Desulfovibrio. The increasing MeHg concentration in rhizosphere could be improved by biochar sensitive microbes such as Saccharimonadales and Clostridia. Network analysis showed that Saccharimonadales and Clostridia were the most prominent keystone taxa in rhizosphere, and the three biochars manipulated abundances of the microbes related to MeHg production in rhizosphere by those biochar sensitive microbes. Therefore, selenium- and chitosan-modified biochar could reduce soil MeHg production by these microorganisms, and is helpful in controlling MeHg contamination in rice.


Assuntos
Carvão Vegetal , Quitosana , Mercúrio , Compostos de Metilmercúrio , Oryza , Selênio , Poluentes do Solo , Compostos de Metilmercúrio/análise , Poluentes do Solo/análise , Mercúrio/análise , Solo
7.
Environ Int ; 178: 108066, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37399771

RESUMO

The plant microbiota can affect plant health and fitness by promoting methylmercury (MeHg) production in paddy soil. Although most well-known mercury (Hg) methylators are observed in the soil, it remains unclear how rice rhizosphere assemblages alter MeHg production. Here, we used network analyses of microbial diversity to identify bulk soil (BS), rhizosphere (RS) and root bacterial networks during rice development at Hg gradients. Hg gradients greatly impacted the niche-sharing of taxa significantly relating to MeHg/THg, while plant development had little effect. In RS networks, Hg gradients increased the proportion of MeHg-related nodes in total nodes from 37.88% to 45.76%, but plant development enhanced from 48.59% to 50.41%. The module hub and connector in RS networks included taxa positively (Nitrososphaeracea, Vicinamibacteraceae and Oxalobacteraceae) and negatively (Gracilibacteraceae) correlating with MeHg/THg at the blooming stage. In BS networks, Deinococcaceae and Paludibacteraceae were positively related to MeHg/THg, and constituted the connector at the reviving stage and the module hub at the blooming stage. Soil with an Hg concentration of 30 mg kg-1 increased the complexity and connectivity of root microbial networks, although microbial community structure in roots was less affected by Hg gradients and plant development. As most frequent connector in root microbial networks, Desulfovibrionaceae did not significantly correlate with MeHg/THg, but was likely to play an important role in the response to Hg stress.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Oryza , Poluentes do Solo , Compostos de Metilmercúrio/análise , Oryza/química , Solo/química , Monitoramento Ambiental , Poluentes do Solo/análise , Mercúrio/análise , Bactérias
8.
Talanta ; 265: 124800, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37392707

RESUMO

Realizing accurate pesticide multiresidue detection in a complex matrix is still a challenge for point-of-care sensing methods. Herein, we introduced background-free and multicolor aptasensors based on bioorthogonal surface-enhanced Raman scattering (SERS) tags and successfully applied them to analyze multiple pesticide residues. The excellent anti-interference and multiplex capability are due to the application of three bioorthogonal Raman reporters involving 4-ethenylbenzenamine (4-EBZM), Prussian blue (PB) and 2-amino-4-cyanopyridine (AMCP) with alkynyl and cyano groups, which demonstrated apparent Raman shift peaks at 1993 cm-1, 2160 cm-1, and 2264 cm-1 in the biologically Raman-silent region, respectively. Ultimately, a detection range of 1-50 nM for acetamiprid, atrazine and malathion was achieved with detection limits of 0.39, 0.57 and 0.16 nM, respectively. The developed aptasensors were successfully used to determine pesticide residues in real samples. These proposed multicolor aptasensors offer an effective strategy for pesticide multiresidue detection with advantages of anti-interference, high specificity and high sensitivity.

9.
J Environ Manage ; 344: 118640, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37478720

RESUMO

Anaerobic digestion (AD) with municipal wastewater contained heavy metal mercury (Hg) highly affects the utilization of activated sludge, and poses severe threat to the health of human beings. However, the biogeochemical transformation of Hg during AD remains unclear. Here, we investigated the biogeochemical transformation and environmental characteristics of Hg and the variations of dominant microbes during AD. The results showed that Hg(II) methylation is dominant in the early stage of AD, while methylmercury (MeHg) demethylation dominates in the later stage. Dissolved total Hg (DTHg) in the effluent sludge decreased with time, while THg levels enhanced to varying degrees at the final stage. Sulfate significant inhibits MeHg formation, reduces bioavailability of Hg(II) by microbes and thus inhibits Hg(II) methylation. Microbial community analysis reveals that strains in Methanosarcina and Aminobacterium from the class of Methanomicrobia, rather than Deltaproteobacteria, may be directly related to Hg(II) methylation and MeHg demethylation. Overall, this research provide insights into the biogeochemical transformation of Hg in the anaerobic digestion of municipal wastewater treatment. This work is beneficial for scientific treatment of municipal wastewater and effluent sludge, thus reducing the risk of MeHg to human beings.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Humanos , Mercúrio/análise , Águas Residuárias , Esgotos , Anaerobiose
10.
Anal Chim Acta ; 1268: 341398, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37268344

RESUMO

In this study, we propose an interference-free SERS-based aptasensor for trace detection of chlorpyrifos (CPF) in real samples. In the aptasensor, gold nanoparticles coated with Prussian blue (Au@PB NPs) were employed as SERS tags to provide a sole and intense Raman emission at 2160 cm-1, which could avoid overlapping with the Raman spectrum of the real samples in 600-1800 cm-1 to improve the anti-matrix effect ability of the aptasensor. Under the optimum conditions, this aptasensor displayed a linear response for CPF detection in the range of 0.1-316 ng mL-1 with a low detection limit of 0.066 ng mL-1. In addition, the prepared aptasensor shows excellent application to determine CPF in cucumber, pear and river water samples. The recovery rates were highly correlated with high-performance liquid chromatography‒mass spectrometry (HPLC‒MS/MS). This aptasensor shows interference-free, specific and sensitive detection for CPF and offers an effective strategy for other pesticide residue detection.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Clorpirifos , Nanopartículas Metálicas , Clorpirifos/análise , Ouro/química , Espectrometria de Massas em Tandem , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos , Limite de Detecção , Aptâmeros de Nucleotídeos/química
11.
Sci Total Environ ; 892: 164597, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37271400

RESUMO

Anthropogenic activities such as mining, smelting, and overapplication of fertilizers contribute to introducing cadmium (Cd) into the biosphere. Cd accumulation in edible plants leads to phytotoxicity and reduces biomass formation and food production, posing a significant threat to global food security. Nitric oxide (NO) is a highly active gaseous signalling molecule involved in regulating plant responses to Cd stress. These responses include the protective role of NO in enhancing plant resistance to Cd exposure via activating the antioxidant defense system, maintaining intracellular redox homeostasis, and initiating the expression of genes relevant to stress defense. However, NO exacerbates Cd toxicity by promoting Cd uptake and accelerating programmed cell death in plants. These contradictory responses render the role of NO in regulating plant performance under Cd exposure highly controversial. To better understand the mechanisms responsible for the dual role of NO, we summarized the current knowledge on (1) the processes of Cd accumulation and detoxification in plants, (2) the pathways of NO synthesis and metabolism under Cd stress, and (3) the function of NO in regulating plant responses to Cd stress at the physiological and molecular levels. From this literature review, the processes responsible for the dual role of NO in plant responses to Cd exposure were deduced, and topics for future studies on the mechanisms of NO-mediated regulation of Cd detoxification in plants were identified.


Assuntos
Cádmio , Óxido Nítrico , Cádmio/toxicidade , Cádmio/metabolismo , Óxido Nítrico/metabolismo , Plantas/metabolismo , Antioxidantes/metabolismo , Oxirredução
12.
Molecules ; 28(12)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37375349

RESUMO

To comprehensively understand the volatile compounds and assess the aroma profiles of different types of Pyrus ussuriensis Maxim. Anli, Dongmili, Huagai, Jianbali, Jingbaili, Jinxiangshui, and Nanguoli were detected via headspace solid phase microextraction (HS-SPME) coupled with two-dimensional gas chromatography/time-of-flight mass spectrometry (GC×GC-TOFMS). The aroma composition, total aroma content, proportion and number of different aroma types, and the relative quantities of each compound were analyzed and evaluated. The results showed that 174 volatile aroma compounds were detected in various cultivars, mainly including esters, alcohols, aldehydes, and alkenes: Jinxiangshui had the highest total aroma content at 2825.59 ng/g; and Nanguoli had the highest number of aroma species detected at 108. The aroma composition and content varied among pear varieties, and the pears could be divided into three groups based on principal component analysis. Twenty-four kinds of aroma scents were detected; among them, fruit and aliphatic were the main fragrance types. The proportions of aroma types also varied among different varieties, visually and quantitatively displaying changes of the whole aroma of the different varieties of pears brought by the changes in aroma composition. This study contributes to further research on volatile compound analysis, and provides useful data for the improvement of fruit sensory quality and breeding work.


Assuntos
Odorantes , Pyrus , Compostos Orgânicos Voláteis , Odorantes/análise , Melhoramento Vegetal , Pyrus/química , Pyrus/genética , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise , Cromatografia Gasosa-Espectrometria de Massas , China
13.
Molecules ; 28(9)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37175308

RESUMO

A novel dual-response fluorescence probe (XBT-CN) was developed by using a fluorescence priming strategy for quantitative monitoring and visualization of hydrazine (N2H4) and hypochlorite (ClO-). With the addition of N2H4/ClO-, the cleavage reaction of C=C bond initiated by N2H4/ClO- was transformed into corresponding hydrazone and aldehyde derivatives, inducing the probe XBT-CN appeared a fluorescence "off-on" response, which was verified by DFT calculation. HRMS spectra were also conducted to confirm the sensitive mechanism of XBT-CN to N2H4 and ClO-. The probe XBT-CN had an obvious fluorescence response to N2H4 and ClO-, which caused a significant color change in unprotected eyes. In addition, the detection limits of XBT-CN for N2H4 and ClO- were 27 nM and 34 nM, respectively. Interference tests showed that other competitive analytes could hardly interfere with the detection of N2H4 and ClO- in a complex environment. In order to realize the point-of-care detection of N2H4 and ClO-, an XBT-CN@hydrogel test kit combined with a portable smartphone was developed. Furthermore, the portable test kit has been applied to the detection of N2H4 and ClO- in a real-world environment and food samples, and a series of good results have been achieved. Attractively, we demonstrated that XBT-CN@hydrogel was successfully applied as an encryption ink in the field of information security. Finally, the probe can also be used to monitor and distinguish N2H4 and ClO- in living cells, exhibiting excellent biocompatibility and low cytotoxicity.


Assuntos
Hidrogéis , Ácido Hipocloroso , Ácido Hipocloroso/química , Sistemas Automatizados de Assistência Junto ao Leito , Espectrometria de Fluorescência/métodos , Corantes Fluorescentes/química , Hidrazinas
14.
J Hazard Mater ; 445: 130589, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-37055993

RESUMO

Over 3000 mercury (Hg)-contaminated sites worldwide contain liquid metallic Hg [Hg(0)l] representing a continuous source of elemental Hg(0) in the environment through volatilization and solubilization in water. Currently, there are few effective treatment technologies available to remove or sequester Hg(0)l in situ. We investigated sonochemical treatments coupled with complexing agents, polysulfide and sulfide, in oxidizing Hg(0)l and stabilizing Hg in water, soil and quartz sand. Results indicate that sonication is highly effective in breaking up and oxidizing liquid Hg(0)l beads via acoustic cavitation, particularly in the presence of polysulfide. Without complexing agents, sonication caused only minor oxidation of Hg(0)l but increased headspace gaseous Hg(0)g and dissolved Hg(0)aq in water. However, the presence of polysulfide essentially stopped Hg(0) volatilization and solubilization. As a charged polymer, polysulfide was more effective than sulfide in oxidizing Hg(0)l and subsequently stabilizing the precipitated metacinnabar (ß-HgS) nanocrystals. Sonochemical treatments with sulfide yielded incomplete oxidation of Hg(0)l, likely resulting from the formation of HgS coatings on the dispersed µm-size Hg(0)l bead surfaces. Sonication with polysulfide also resulted in rapid oxidation of Hg(0)l and precipitation of HgS in quartz sand and in the Hg(0)l-contaminated soil. This research indicates that sonochemical treatment with polysulfide could be an effective means in rapidly converting Hg(0)l to insoluble HgS precipitates in water and sediments, thereby preventing its further emission and release to the environment. We suggest that future studies are performed to confirm its technical feasibility and treatment efficacy for remediation applications.

15.
Environ Pollut ; 324: 121340, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36828354

RESUMO

Rice consumption is an essential cause of mercury (Hg) exposure for humans in Asia. However, the mechanism of Hg transport and accumulation in rice plants (Oryza sativa L.) remains unclear. Here, rice genotypes with contrasting Hg uptake and translocation abilities, i.e. H655 (high Hg-accumulator) and H767 (low Hg-accumulator), were selected from 261 genotypes. Through comparative physiological and transcriptome analyses, we investigated the processes responsible for the relationship between Hg accumulation, transport and tolerance. The results showed significant stimulation of antioxidative metabolism, particularly glutathione (GSH) accumulation, and up-regulated expression of regulatory genes of glutathione metabolism for H655, but not for H767. In addition, up-regulated expression of GSH S-transferase (GST) and OsPCS1 in H655 that catalyzes the binding of Hg and GSH, enhances the Hg detoxification capacity, while high-level expression of YSL2 in H655 enhances the transport ability for Hg. Conclusively, Hg accumulation in rice is a consequence of enhanced expression of genes related to Hg binding with GSH and Hg transport. With these results, the present study contributes to the selection of rice genotypes with limited Hg accumulation and to the mitigation of Hg migration in food chains thereby enhancing nutritional safety of Hg-polluted rice fields.


Assuntos
Mercúrio , Oryza , Humanos , Oryza/metabolismo , Mercúrio/análise , Antioxidantes/metabolismo , Glutationa/metabolismo , Genótipo
16.
J Hazard Mater ; 442: 130064, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36182885

RESUMO

Previous research has found total mercury (THg) and methylmercury (MeHg) levels increase with litterfall decay, thus suggesting litterfall decomposition plays an essential role in the biogeochemical transformation of mercury (Hg). However, it remains unclear how Hg accumulates in the decaying litter, how bacterial taxa networks vary and what roles various microorganisms play during litterfall decomposition, especially nitrogen (N)-fixing, MeHg-degrading and Hg-methylating microbes. Here, we demonstrated as degradation proceeded, a gradually-complex network evolved for litterfall bacteria for the subtropical mixed broadleaf-conifer (MBC) forest, whereas a relatively static network existed for the evergreen broadleaf (EB) forest. N-fixing and MeHg-degrading bacteria dominated throughout litterfall decomposition process, with relative abundances of N-fixing genera and nifH copies maximum and relative abundances of MeHg-degrading bacteria and merAB copies minimum in summer. Hence, N-fixing bacteria likely mediate THg increase in the decomposing litterfall, while MeHg enhancement may be regulated by aerobic MeHg-degrading microbes which can transform MeHg to inorganic divalent Hg (Hg2+) or further to elemental Hg (Hg0). Together, this work elucidates variations of N-fixing and MeHg-degrading microbes in decaying litterfall and their relationships with Hg accumulation, providing novel insights into understanding the biogeochemical cycle of Hg in the forest ecosystem.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Poluentes Químicos da Água , Compostos de Metilmercúrio/química , Mercúrio/análise , Ecossistema , Nitrogênio , Estações do Ano , Monitoramento Ambiental , Bactérias , Poluentes Químicos da Água/análise
17.
Foods ; 11(23)2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36496570

RESUMO

Lactoferrin (Lf), as a popular nutritional fortification in dairy products, has the ability regulate the body's immune system and function as a broad-spectrum antibacterial, which is of great significance to the growth and development of infants and children. Herein, an indirect competitive enzyme-linked aptamer assay (ELAA) kit was established for rapid, sensitive, and visual determination of Lf in dairy products. In the construction, the Lf aptamer was conjugated with horseradish peroxidase (HRP) as the recognition probe and aptamer complementary strand (cDNA) were anchored onto the microplate as the capture probe. The recognition probes were first mixed with a sample solution and specifically bound with the contained Lf, then added into the microplate in which the free recognition probes in the mixture were captured by the capture probe. After washing, the remaining complex of cDNA/Aptamer/HRP in the microplate was conducted with a chromogenic reaction through HRP, efficiently catalyzing the substrate 3, 3', 5, 5'-tetramethylbenzidine (TMB), therefore the color shade would directly reflect Lf concentration. Under the optimization conditions, a good linear relationship (R2, 0.9901) was obtained in the wide range of 25-500 nM with the detection limit of 14.01 nM and a good specificity, as well as the reliable recoveries. Furthermore, the ELAA kits achieved the Lf determination with an accuracy of 79.71~116.99% in eleven samples, which consisted of three kinds of dairy products: including goat milk powder, cow milk powder, and nutrition drop. Moreover, the results were also validated by the high-performance capillary electrophoresis (HPCE) method. The ELAA kit provides a simple and convenient determination for Lf in dairy products, and it is highly expected to be commercialized.

19.
J Microbiol Methods ; 199: 106532, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35777598

RESUMO

Anaerobic activated sludge is rich in humic substances and water, leading to significant differences in the stability of metagenomic DNA and metatranscriptomic RNA. Thus, it is of great difficulty to exact high-quality and high-yield DNA and RNA from them, especially those cultured at a wide range of temperatures. Here, we established fast and effective DNA and RNA extraction methods based on current commercial kits. The modified methods combined liquid nitrogen grinding with kits, achieving notable improvements in concentrations, yields, purity and integrities for both DNA and RNA. The ratios of OD260/280 of the metagenomic DNA were between 1.81 ± 0.03 and 1.83 ± 0.02, while OD260/280 and OD260/230 of the metatranscriptomic RNA ranged from 1.96 ± 0.01 to 2.13 ± 0.03 and from 1.94 ± 0.02 to 2.30 ± 0.03 respectively. Metagenomic DNA and metatranscriptomic RNA obtained by the modified methods perfectly met the requirements of second- and third-generation sequencing, providing valuable reference for extracting high-quality metagenomic DNA and metatranscriptomic RNA from environmental samples of high water content and humic substances under temperatures ranging from 18 °C to 52 °C.


Assuntos
RNA , Esgotos , Anaerobiose , DNA , Substâncias Húmicas/análise , RNA/genética , Temperatura , Água
20.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(2): 208-212, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-35538754

RESUMO

Objective To study the influence of recombinant bovine basic fibroblast growth factor as an adjuvant therapy on scar alleviation and inflammatory cytokines in patients with atrophic acne scar. Methods The random number table was employed to randomly assign 120 patients with atrophic acne scar into a test group and a control group.Both groups of patients were treated with CO2 lattice laser.After the operation,the control group was routinely smeared with erythromycin ointment and the test group was coated with recombinant bovine basic fibroblast growth factor gel.The clinical efficacy,clinical indicators,scar alleviation,and inflammatory cytokine levels before and after treatment were compared,and adverse reactions were counted. Results The test group had higher total effective rate(P=0.040) and lower total incidence of adverse reactions(P=0.028) than the control group.Compared with the control group,the test group showcased short erythema duration after treatment(P=0.025),early scab forming(P=0.002),and early edema regression(P<0.001).After treatment,the proportion of grade 1 scars graded by Goodman and Baron's acne scar grading system in the test group and control group increased(P=0.001,P=0.027),and the proportion of grade 4 scars decreased(P<0.001,P=0.034).Moreover,the proportion of grade 1 scars in the test group was higher than that in the control group(P=0.031) after treatment,and the proportion of grade 4 scars presented an opposite trend(P=0.031).After treatment,the levels of tumor necrosis factor-α(TNF-α) and interleukin-1ß(IL-1ß) in both groups declined(all P<0.001),and the test group had lower TNF-α and IL-1ß levels than the control group(all P<0.001). Conclusion The recombinant bovine basic fibroblast growth factor gel as an adjuvant therapy of CO2 lattice laser can effectively alleviate the atrophic acne scar,relieve local inflammatory reaction,and has good curative effect and less adverse reactions.


Assuntos
Acne Vulgar , Cicatriz , Acne Vulgar/complicações , Acne Vulgar/tratamento farmacológico , Animais , Atrofia/complicações , Dióxido de Carbono , Bovinos , Cicatriz/tratamento farmacológico , Cicatriz/etiologia , Cicatriz/patologia , Fator 2 de Crescimento de Fibroblastos/uso terapêutico , Humanos , Resultado do Tratamento , Fator de Necrose Tumoral alfa
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