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1.
J Environ Manage ; 340: 117969, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37084645

RESUMO

The coexistence of nanoplastics and antibiotics in the aquatic environment has raised a complicated risk for ecosystems and human health. How the environmental factors e.g., light, regulate the interaction between nanoplastics and antibiotics and the resulting combined toxicity is poorly understood. Here, we investigated the individual and combined toxicity of polystyrene nanoplastics (nPS, 100 mg L1) and sulfamethoxazole (SMX, 2.5 and 10 mg L-1) toward the microalgae Chlamydomonas reinhardtii under low (LL, 16 µmol m-2·s-1), normal (NL, 40 µmol m-2·s-1), and high light (HL, 150 µmol m-2·s-1) in terms of cellular responses. Results indicated that the joint toxicity of nPS and SMX commonly exhibited a strong antagonistic/mitigative effect under LL/NL at 24 h, and under NL at 72 h. nPS could adsorb more SMX under LL/NL at 24 h (1.90/1.33 mg g-1) and under NL at 72 h (1.01 mg g-1), thereby alleviating SMX toxicity to C. reinhardtii. However, the self-toxicity of nPS had a negative influence on the degree of antagonism between nPS and SMX. The experimental results coupled with computational chemistry further revealed that the adsorption capacity of SMX on nPS was stimulated by low pH under LL/NL at 24 h (∼7.5), while by less co-existing saline ions (0.83 ppt) and algae-derived dissolved organic matter (9.04 mg L-1) under NL at 72 h. nPS toxicity that was responsible for the toxic action modes was mainly attributed to the shading effect induced by hetero-aggregation and hindrance of light transmittance (>60%), as well as being regulated by additives leaching (0.49-1.07 mg L-1) and oxidative stress. Overall, these findings provided a critical basis for the risk assessment and management of multiple pollutants in the complex natural environment.


Assuntos
Chlamydomonas reinhardtii , Microalgas , Nanopartículas , Poluentes Químicos da Água , Humanos , Poliestirenos/toxicidade , Microplásticos/toxicidade , Sulfametoxazol/toxicidade , Ecossistema , Poluentes Químicos da Água/análise , Antibacterianos/farmacologia
2.
Zhongguo Zhong Yao Za Zhi ; 47(2): 358-366, 2022 Jan.
Artigo em Zh | MEDLINE | ID: mdl-35178977

RESUMO

Taste is an important factor affecting the medicinal properties of oral preparations and patient compliance with medication, and also an important evaluation index for oral preparation design and clinical application. How to characterize the taste objectively, accurately, simply, and efficiently is a bottleneck problem that restricts the taste design, development, and utilization of oral preparations. At present, the commonly used taste assessment methods for oral preparations are traditional human taste panel, electronic tongue, animal preference test, in vitro release study, and electrophysiological test. The traditional human taste panel is the first choice for taste evaluation, but it is limited by poor subjectivity and reproducibility. Therefore, despite some limitations, the other four taste assessment methods have been applied in the pharmaceutical industry as auxiliary methods. This study reviewed the detection principles, applicability, advantages, and disadvantages of the above methods to provide references for the taste correction research and taste assessment of oral preparations, improve patient compliance and the competitiveness of oral preparation products in the industry, and promote the development of oral preparation technologies.


Assuntos
Preparações Farmacêuticas , Paladar , Administração Oral , Animais , Nariz Eletrônico , Humanos , Reprodutibilidade dos Testes
3.
Zhongguo Zhong Yao Za Zhi ; 47(8): 2099-2108, 2022 Apr.
Artigo em Zh | MEDLINE | ID: mdl-35531726

RESUMO

According to the polarity of different components in Sanpian Decoction, two fingerprints were established. Then the substance benchmark freeze-dried powder of 15 batches of Sanpian Decoction was prepared, followed by the determination of the fingerprints, index component content, and dry extract rates, the identification of attribution of characteristic peaks, and the calculation of similarities between these fingerprints and the reference(R), the content and transfer rate ranges of ferulic acid, sinapine thiocyanate, liquiritin, and glycyrrhizic acid, and the dry extract rate range. The results showed that the similarities of 15 batches of the substance benchmark fingerprints with R were all greater than 0.900.Further summarization of the characteristic peaks revealed that there were a total of 20 characteristic peaks in fingerprint 1, among which, eight were from Sinapis Semen, four from Paeoniae Radix Alba, six from Chuanxiong Rhizoma, and two from Glycyrrhizae Radix et Rhizoma. A total of 16 characteristic peaks were observed in fingerprint 2, including one from Sinapis Semen, three from Paeoniae Radix Alba, eight from Chuanxiong Rhizoma, and four from Glycyrrhizae Radix et Rhizoma. The average dry extract rate of 15 batches of substance benchmarks was 18.25%, with a dry extract rate range of 16.28%-20.76%. The index component content and transfer rate ranges were listed as follows: 0.15%-0.18% and 38.81%-58.05% for ferulic acid; 0.26%-0.42% and 36.51%-51.02% for sinapine thiocyanate; 0.09%-0.15% and 48.80%-76.61% for liquiritin; 0.13%-0.24% and 23.45%-35.61% for glycyrrhizic acid. The fingerprint, dry extract rate, and index component content determination was combined for analyzing the quality value transfer of substance benchmarks in the classic prescription Sanpian Decoction.The established quality evaluation method for the substance benchmarks was stable and feasible, which has provided a basis for the quality control of Sanpian Decoction and the follow-up development of related preparations.


Assuntos
Medicamentos de Ervas Chinesas , Paeonia , Benchmarking , Cromatografia Líquida de Alta Pressão , Ácido Glicirrízico/análise , Controle de Qualidade , Tiocianatos
4.
Mol Breed ; 41(12): 74, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37309519

RESUMO

The basic helix-loop-helix (bHLH) transcription factor has been shown to play an important role in various physiological processes. However, its functions and mechanisms in drought tolerance still remain poorly understood. Here, we reported a bHLH transcription factor - CgbHLH001 - from Chenopodium glaucum, which was able to confer drought tolerance in maize. CgbHLH001-overexpressed maize lines exhibited drought-tolerant phenotype and improved ear traits by accumulating the contents of soluble sugar and proline and elevating the activities of antioxidant enzymes (SOD, POD, and CAT) under drought stress, accompanying with the upregulation of some stress-related genes, which may balance the redox and osmotic homeostasis compared with the non-transgenic and CgbHLH001-RNAi plants. These findings suggest that CgbHLH001 can confer drought tolerance and has the potential for utilization in improving drought resistance in maize breeding. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-021-01267-4.

5.
Zhongguo Zhong Yao Za Zhi ; 46(4): 810-819, 2021 Feb.
Artigo em Zh | MEDLINE | ID: mdl-33645085

RESUMO

By preparing 15 batches of lyophilized powder samples of substance benchmark in Houpo Wenzhong Decoction,the fingerprint,index component content and extract rate were determined,and the characteristic peaks,the range of similarity with the reference map,the content range and transfer rate range of magnolol,hesperidin,glycyrrhizic acid and pinocembrin,the extract rate range and the change range were clarified. The results showed that the similarity between the fingerprint of substance benchmark and the reference map R generated from the 15 batches of substance benchmark samples was higher than 0. 90. The assignment of the characteristic peaks in the full prescription's fingerprint of the herbs except Poria cocos was clarified. Nineteen characteristic peaks were assigned,and 12 characteristic peaks were assigned by the reference substance,of which 4 were from Magnolia ocinalis Cortex,5 from Exocarpium Citri Rubrum,2 from Radix aucklandiae,3 from Glycyrrhiza Radix et Rhizoma,4 from Semen Alpiniae Katsumadai,and one from Rhizoma Zingiberis and Zingiber officinale Roscoe. The index component content range and transfer rate range were 0. 80%-1. 14% and 20. 25%-39. 61% for hesperidin,0. 49%-0. 79% and 23. 09%-33. 87%for glycyrrhizic acid,0. 03%-0. 07% and 3. 55%-10. 09% for pinocembrin,0. 15%-0. 38% and 8. 08%-24. 35% for magnolol. The extract rate range and the change range were22. 60%-25. 57% and 12. 67%-23. 68% respectively. In this study,we introduced the concepts of index component content,fingerprint,extract rate,explored the transfer relation of quality value transmitting of substance benchmark in Houpo Wenzhong Decoction,and initially established the quality standard of Houpo Wenzhong Decoction,all of which would provide ideas for the development and research of similar prescriptions.


Assuntos
Medicamentos de Ervas Chinesas , Glycyrrhiza , Benchmarking , Cromatografia Líquida de Alta Pressão , Controle de Qualidade
6.
Environ Microbiol ; 22(11): 4761-4778, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32896070

RESUMO

Interactions between phytoplankton and bacteria play major roles in global biogeochemical cycles and oceanic nutrient fluxes. These interactions occur in the microenvironment surrounding phytoplankton cells, known as the phycosphere. Bacteria in the phycosphere use either chemotaxis or attachment to benefit from algal excretions. Both processes are regulated by quorum sensing (QS), a cell-cell signalling mechanism that uses small infochemicals to coordinate bacterial gene expression. However, the role of QS in regulating bacterial attachment in the phycosphere is not clear. Here, we isolated a Sulfitobacter pseudonitzschiae F5 and a Phaeobacter sp. F10 belonging to the marine Roseobacter group and an Alteromonas macleodii F12 belonging to Alteromonadaceae, from the microbial community of the ubiquitous diatom Asterionellopsis glacialis. We show that only the Roseobacter group isolates (diatom symbionts) can attach to diatom transparent exopolymeric particles. Despite all three bacteria possessing genes involved in motility, chemotaxis, and attachment, only S. pseudonitzschiae F5 and Phaeobacter sp. F10 possessed complete QS systems and could synthesize QS signals. Using UHPLC-MS/MS, we identified three QS molecules produced by both bacteria of which only 3-oxo-C16:1 -HSL strongly inhibited bacterial motility and stimulated attachment in the phycosphere. These findings suggest that QS signals enable colonization of the phycosphere by algal symbionts.


Assuntos
Aderência Bacteriana , Diatomáceas/microbiologia , Locomoção , Fitoplâncton/microbiologia , Percepção de Quorum/fisiologia , 4-Butirolactona/análogos & derivados , 4-Butirolactona/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Aderência Bacteriana/genética , Genes Bacterianos , Locomoção/genética , Microbiota , Oceanos e Mares , Percepção de Quorum/genética
7.
Chembiochem ; 21(9): 1293-1297, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-31755629

RESUMO

In 1994, the first DNAzyme named GR5 was reported, which specifically requires Pb2+ for its RNA cleavage activity. Three years later, the 8-17 DNAzyme was isolated. The 8-17 DNAzyme and the related 17E DNAzyme are also most active with Pb2+ , although other divalent metals can work as well. GR5 and 17E have the same substrate sequence, and their catalytic loops in the enzyme strands also have a few similar and conserved nucleotides. Considering these, we hypothesized that 17E might be a special form of GR5. To test this hypothesis, we performed systematic rational evolution experiments to gradually mutate GR5 toward 17E. By using the activity ratio in the presence of Pb2+ and Mg2+ for defining these two DNAzymes, the critical nucleotide was identified to be T12 in 17E for metal specificity. In addition, G9 in GR5 is a position not found in most 17E or 8-17 DNAzymes, and G9 needs to be added to rescue GR5 activity if T12 becomes a cytosine. This study highlights the links between these two classic and widely used DNAzymes, and offers new insight into the sequence-activity relationship related to metal selectivity.


Assuntos
DNA Catalítico/metabolismo , Chumbo/química , Magnésio/química , RNA/metabolismo , Técnicas Biossensoriais , Catálise , RNA/genética
8.
Analyst ; 145(4): 1384-1388, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-31998880

RESUMO

GR5 is the first reported DNAzyme, which has RNA cleavage activity in the presence of Pb2+. Due to its excellent selectivity, GR5 has been a popular DNAzyme for developing biosensors for Pb2+. The activity of DNAzymes is often affected by pH and salt, which may in turn affect the sensitivity of related sensors. Although pH can be readily controlled by using a buffer, the effect of salt is more complex. To have a systematic understanding, we herein measured the cleavage activity of GR5 in various concentrations of Na+ and Mg2+. Both metals inhibited the DNAzyme with Pb2+, and the inhibition constants were 1.8 mM Mg2+ and 33.4 mM Na+. For anions, F- inhibited GR5 more strongly than Br-, while Cl- was the least inhibiting anion, which was consistent with the solubility of their lead salts. The reaction can work similarly in many Good's buffers, while phosphate buffer should be avoided. Finally, GR5 is an optimal sequence based on the truncation and elongation studies. This study reveals important solution conditions that should be considered when designing and testing related biosensors for metal detection.


Assuntos
Técnicas Biossensoriais/métodos , Colorimetria/métodos , DNA Catalítico/química , Chumbo/análise , Ânions , Sequência de Bases , Soluções Tampão , Cátions , DNA Catalítico/metabolismo , Concentração de Íons de Hidrogênio , Magnésio/química , Concentração Osmolar , Sensibilidade e Especificidade , Alinhamento de Sequência , Sódio/química
9.
Fish Shellfish Immunol ; 73: 75-83, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29196031

RESUMO

The present study was conducted to evaluate the effects of various Bacillus coagulans feeding patterns on growth, antioxidant parameter and Nrf2 pathway in juvenile gibel carp. The similar size of gibel carp (initial weight: 14.33 ± 0.15 g) were subjected to three levels of B. coagulans supplementation (0, 500, and 1000 mg/kg) and two feeding modes (supplementing B. coagulans continuously or for two days of B. coagulans after 5 days of a basal diet) according to a 3 × 2 factorial design. The fish that were continuously fed 500 mg/kg B. coagulans (P2) and those fed the first basal diet for 5 days followed by 500 mg/kg or 1000 mg/kg B.coagulans for 2 days (P4 or P5) showed higher weight gain rate and specific growth rate than the other groups. Blood respiratory burst (RB), myeloperoxidase (MPO), and anti-superoxide anion free radical (AFASER) activities in the P4 group were higher than those of the control. White blood cell count (WBC), RB activity, MPO activity, and glutathione (GSH) content in the P5 group were also higher than those of the control. A similar higher trend was observed in the gene expressions of NADPH oxidase 2 (NOX2), NFE2-related factor (Nrf2), Kelch-like-ECH-associated protein(Keap1) in the P4 and NOX2, NRF2, CNC homolog 1 (Bach1), peroxiredoxin 2 (Prx2) in the P5 group compared with the control. Additionally, we observed a significantly lower level of plasma aspartate aminotransferase (AST), lower activity of alanine aminotransferase (ALT), a higher level of MPO, higher GPX activity, and increased NRF2 and Prx2 expression were all observed in the P2 treatment group compared with the control. Furthermore, the malondialdehyde (MDA) content in the P2, P3, and P4 groups was lower than that of the control. These results indicate that a diet supplemented with appropriate levels of B.coagulans could improve the growth, immune response, and antioxidant capability of gibel carp. We concluded that the pattern of two days of 500 or 1000 mg/kg B. coagulans after 5 days of a basal diet was recommended for gibel carp.


Assuntos
Antioxidantes/metabolismo , Bacillus coagulans/química , Carpa Dourada/fisiologia , Imunidade Inata , Probióticos/farmacologia , Transdução de Sinais , Ração Animal/análise , Animais , Dieta/veterinária , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Carpa Dourada/crescimento & desenvolvimento , Carpa Dourada/imunologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Probióticos/administração & dosagem
10.
Med Sci Monit ; 24: 5035-5040, 2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-30026459

RESUMO

BACKGROUND The aim of this study was to investigate the association between polymorphisms of the epidermal growth factor receptor (EGFR) gene with the risk of Alzheimer's disease (AD) in a Chinese Han population. MATERIAL AND METHODS A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay was used to genotype 139 patients with AD and 152 healthy control individuals. The Hardy-Weinberg equilibrium (HWE) was analyzed using the chi-squared (χ²) test, and genotype and allele frequencies were compared between the two population groups, using the χ² test. The odds ratios (ORs) and corresponding 95% confidence intervals (CI) were calculated to express the degree of risk of AD resulting from polymorphisms in the EGFR gene. Linkage disequilibrium among EGFR polymorphisms was analyzed using the Haploview bioinformatics software. RESULTS The CC genotype and C allele frequencies of rs730437 were significantly lower in patients with AD compared with the controls (P=0.037), indicating that rs730437 was associated with a reduced risk of AD (CC vs. AA: OR=0.446, 95% CI=0.207-0.960) (C vs. A: OR=0.702, 95% CI=0.502-0.980). The presence of the TT genotype of rs1468727 significantly reduced the risk of AD (P=0.003; OR=0.333, 95% CI=0.160-0.691), and T allele carriers of rs1468727 had a 0.605-fold increased risk of AD. Haplotype A-C-C was significantly correlated with an increased risk of AD (OR=1.922, 95% CI=1.130-3.269). CONCLUSIONS In a Han Chinese population, EGFR gene polymorphisms, rs730437 and rs1468727 and haplotype A-C-C were shown to be possible protective factors for the development of AD.


Assuntos
Doença de Alzheimer/genética , Receptores ErbB/genética , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Povo Asiático/genética , Estudos de Casos e Controles , China/epidemiologia , Receptores ErbB/metabolismo , Feminino , Frequência do Gene , Genes erbB-1 , Predisposição Genética para Doença , Haplótipos , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores de Risco
11.
Nano Lett ; 16(1): 114-20, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26674206

RESUMO

We present the synthesis of Co2FeGa Heusler nanowires and the results of our investigations on their three-dimensional (3D) electric and magnetic internal and external fields mapped by electron holographic tomography (EHT). These fields will be of great importance in next-generation nanomagnets integrated in spintronics and memory devices. The Co2FeGa nanowires with a L21 ordered structure are prepared by a SBA-15 silica-assisted method. The magnetic dipole-like stray fields of several Co2FeGa nanowires are revealed by holographically reconstructed phase images. Based on the measured magnetic phase shifts of an individual nanowire and its 3D reconstruction using EHT, we obtain an internal magnetic induction with a magnitude of 1.15 T and a nonmagnetic surface layer of 10 nm thickness. Furthermore, we also reconstruct the 3D distribution of the electrostatic potential of the same nanowire.

12.
Bull Environ Contam Toxicol ; 99(6): 719-727, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29080111

RESUMO

The ecotoxicity of α-Fe2O3 nanoparticles (NPs) and its interaction with a typical natural organic matter (NOM), fulvic acid (FA) on the physiological responses of Synechococcus sp. PCC7942 was studied. α-Fe2O3 NPs inhibited the algae growth at concentration higher than 10 mg L-1 and induced oxidative stress, indicated by enhanced antioxidant enzymes activities, elevated protein and sugar content. FA could efficiently recover cell growth and reduce antioxidant enzyme activities which induced by α-Fe2O3 NPs, indicating the toxicity of NPs was alleviated in the presence of FA. α-Fe2O3 NPs could form large aggregates coating on cell surface and inhibit cell growth. FTIR spectra verified FA interacted with α-Fe2O3 NPs through carboxyl groups, partly replaced the binding sites of α-Fe2O3 NPs on algal cell walls, thus reduced NPs aggregates coating on cell surface. This favors reducing the oxidative stress caused by direct contact and increasing light availability, thus mitigate NPs toxicity.


Assuntos
Benzopiranos/química , Compostos Férricos/química , Nanopartículas/química , Synechococcus/fisiologia , Antioxidantes , Estresse Oxidativo , Synechococcus/metabolismo
13.
Nanotechnology ; 26(35): 355601, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26245382

RESUMO

We demonstrate that the combination of x-ray irradiation and capping by polyethylene glycol (PEG) produces excellent flexibility in controlling the structure of Au-Pd nanoparticles while preserving their catalytic performance. We specifically adopted two different fabrication methods: co-reduction and seed-assisted reduction. In both cases, precursor composition plays an important role in controlling the phases and size of the bimetallic nanoparticles. The optimal catalytic performance is obtained with the highest Pd concentration and when the nanoparticles consist of a Au core and a Pd shell.

14.
J Ind Microbiol Biotechnol ; 42(4): 543-51, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25605047

RESUMO

It has been found that recombinant Saccharomyces cerevisiae 6525 can produce high concentration of ethanol in one-step fermentation from the extract of Jerusalem artichoke tubers or inulin. However, the utilization rate of raw materials was low and the fermentation process was costly and complicated. Therefore, in this study, after the optimum processing conditions for ethanol production in fed-batch fermentation were determined in flask, the recombinant S. cerevisiae 6525 was first used to produce ethanol from the dry powder of Jerusalem artichoke tubers in 5-L agitating fermentor. After 72 h of fermentation, around 84.3 g/L ethanol was produced in the fermentation liquids, and the conversion efficiency of inulin-type sugars to ethanol was 0.453, or 88.6 % of the theoretical value of 0.511. This study showed high feasibility of bioethanol industrial production from the Jerusalem artichoke tubers and provided a basis for it in the future.


Assuntos
Etanol/metabolismo , Fermentação , Helianthus/metabolismo , Tubérculos/metabolismo , Saccharomyces cerevisiae/metabolismo , Técnicas de Cultura Celular por Lotes , Reatores Biológicos , Etanol/provisão & distribuição , Estudos de Viabilidade , Helianthus/química , Inulina/metabolismo , Tubérculos/química , Saccharomyces cerevisiae/genética , Fatores de Tempo
15.
J Hazard Mater ; 476: 135062, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38959831

RESUMO

Microplastics (MPs) are emerging pollutants, causing potential threats to aquatic ecosystems and serious concern in aggregating with microalgae (critical primary producers). When entering water bodies, MPs are expected to sink below the water surface and disperse into varying water compartments with different light intensities. However, how light influences the aggregation processes of algal cells onto MPs and the associated molecular coupling mechanisms and derivative risks remain poorly understood. Herein, we investigated the aggregation behavior between polystyrene microplastics (mPS, 10 µm) and Chlorella pyrenoidosa under low (LL, 15 µmol·m-2·s-1), normal (NL, 55 µmol·m-2·s-1), and high light (HL, 150 µmol·m-2·s-1) conditions from integrated in vivo and in silico assays. The results indicated that under LL, the mPS particles primarily existed independently, whereas under NL and HL, C. pyrenoidosa tightly bounded to mPS by secreting more protein-rich extracellular polymeric substances. Infrared spectroscopy analysis and density functional theory calculation revealed that the aggregation formation was driven by non-covalent interaction involving van der Waals force and hydrogen bond. These processes subsequently enhanced the deposition and adherence capacity of mPS and relieved its phytotoxicity. Overall, our findings advance the practical and theoretical understanding of the ecological impacts of MPs in complex aquatic environments.

16.
Mar Environ Res ; 196: 106414, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38394975

RESUMO

Estuaries, acting as transitional habitats receiving species introductions from both freshwater and marine sources, undergo significant impacts from global climate changes. Planktonic microorganisms contribute significantly to estuarine biodiversity and ecological stability. These microorganisms primarily fall into three groups: eukaryotic plankton, particle-associated bacteria, and free-living bacteria. Understanding the structural characteristics and interactions within these subcommunities is crucial for comprehending estuarine dynamics. We collected samples from three distinct locations (< 0.1 PSU, 6.6 PSU, and 19 PSU) within the Yangtze River estuary. Samples underwent analysis for physicochemical indicators, while microbial communities were subjected to 16S/18S rRNA amplicon sequencing. Additionally, simulated mixing experiments were conducted using samples of varying salinities. Estuary samples, combined with simulated experiments, were employed to collectively examine the structural characteristics and assembly processes of estuarine microbes. Our research highlights the considerable impact of phylogenetic classification on prokaryotic behavior in these communities. We observed a transition in assembly processes from primarily stochastic for particle-associated bacteria to a predominant influence of homogeneous selection as salinity increased. Particle-associated bacterial communities exhibited a greater influence of stochastic processes compared to free-living bacteria, showcasing higher stability in diversity. The variations in composition and structure of estuarine microbial subcommunities were influenced by diverse environmental factors. Particle-associated bacteria displayed elevated network characterization values and established closer interactions with eukaryotic plankton. Structural equation modeling (SEM) analysis revealed that free-living bacteria displayed a heightened sensitivity to environmental factors and exerted a more significant influence on assembly processes and network characteristics. Simulated mixing in these environments resulted in the loss of species with similar microbial taxonomic relationships. The functioning of bacterioplankton is influenced by salinity and the processes governing their assembly, particularly in relation to different living states. These findings significantly contribute to our understanding of the intricate interplay between prokaryotic and eukaryotic plankton microorganisms in highly dynamic environments, laying a robust foundation for further exploration into the ecological mechanisms governing microbial dynamics in estuaries.


Assuntos
Microbiota , Plâncton , Rios , Estuários , Filogenia , Organismos Aquáticos , Bactérias/genética , Ecossistema
17.
Sci Total Environ ; 926: 171909, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38522526

RESUMO

Salinity stress in estuarine environments poses a significant challenge for microalgal survival and proliferation. The interaction between microalgae and bacteria shows promise in alleviating the detrimental impacts of salinity stress on microalgae. Our study investigates this interaction by co-cultivating Chlorella sorokiniana, a freshwater microalga, with a marine growth-promoting bacterium Pseudomonas gessardii, both of which were isolated from estuary. In this study, bacteria were encapsulated using sodium alginate microspheres to establish an isolated co-culture system, preventing direct exposure between microalgae and bacteria. We evaluated microalgal responses to different salinities (5 PSU, 15 PSU) and interaction modes (free-living, gel-encapsulated), focusing on growth, photosynthesis, cellular metabolism, and extracellular polymeric substances (EPS) properties. High salinity inhibited microalgal proliferation, while gel-fixed interaction boosted Chlorella growth rate by 50.7 %. Both attached and free-living bacteria restored Chlorella's NPQ to normal levels under salt stress. Microalgae in the free-living interaction group exhibited a significantly lower respiratory rate compared to the pure algae group (-17.2 %). Increased salinity led to enhanced EPS polysaccharide secretion by microalgae, particularly in interaction groups (19.7 %). Both salt stress and interaction increased the proportion of aromatic proteins in microalgae's EPS, enhancing its stability by modulating EPS glycosidic bond C-O-C and protein vibrations. This alteration caused microalgal cells to aggregate, free-living bacteria co-culture group, and fixed co-culture group increasing by 427.5 %, 567.1 %, and 704.1 %, respectively. In gel-fixed bacteria groups, reduced neutral lipids don't accumulate starch instead, carbon redirects to cellular growth, aiding salt stress mitigation. These synergistic activities between salinity and bacterial interactions are vital in mitigating salinity stress, improving the resilience and growth of microalgae in saline conditions. Our research sheds light on the mechanisms of microalgal-bacterial interactions in coping with salt stress, offering insights into the response of estuarine microorganisms to global environmental changes and their ecological stability.


Assuntos
Chlorella , Microalgas , Microalgas/metabolismo , Alginatos/metabolismo , Água Doce , Bactérias , Salinidade , Biomassa
18.
ScientificWorldJournal ; 2013: 289537, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23533346

RESUMO

Responses of Ulva prolifera and Ulva linza to Cd(2+) stress were studied. We found that the relative growth rate (RGR), Fv/Fm, and actual photochemical efficiency of PSII (Yield) of two Ulvaspecies were decreased under Cd(2+) treatments, and these reductions were greater in U. prolifera than in U. linza. U. prolifera accumulated more cadmium than U. linza under Cd(2+) stress. While U. linza showed positive osmotic adjustment ability (OAA) at a wider Cd(2+) range than U. prolifera. U. linza had greater contents of N, P, Na(+), K(+), and amino acids than U. prolifera. A range of parameters (concentrations of cadmium, Ca(2+), N, P, K(+), Cl(-), free amino acids (FAAs), proline, organic acids and soluble protein, Fv/Fm, Yield, OAA, and K(+)/Na(+)) could be used to evaluate cadmium resistance in Ulva by correlation analysis. In accordance with the order of the absolute values of correlation coefficient, contents of Cd(2+) and K(+), Yield, proline content, Fv/Fm, FAA content, and OAA value of Ulva were more highly related to their adaptation to Cd(2+) than the other eight indices. Thus, U. linza has a better adaptation to Cd(2+) than U. prolifera, which was due mainly to higher nutrient content and stronger OAA and photosynthesis in U. linza.


Assuntos
Cloreto de Cádmio/farmacologia , Complexo de Proteína do Fotossistema II/análise , Estresse Fisiológico , Ulva/fisiologia , Adaptação Fisiológica , Aminoácidos/análise , Cádmio/química , Carotenoides/análise , Clorofila/análise , Nitrogênio/análise , Osmose , Fósforo/análise , Fotossíntese , Complexo de Proteína do Fotossistema II/química , Potássio/análise , Sódio/análise , Especificidade da Espécie , Ulva/química , Ulva/efeitos dos fármacos
19.
Zhonghua Nan Ke Xue ; 19(4): 315-20, 2013 Apr.
Artigo em Zh | MEDLINE | ID: mdl-23678709

RESUMO

OBJECTIVE: To explore the expressions of SIgA and alpha l-AR in benign prostatic hyperplasia (BPH) complicated by chronic prostatitis (CP) and their implications. METHODS: According to the preoperative findings of expressed prostatic secretion (EPS), transrectal prostate ultrasonography, prostate-specific antigen (PSA), international prostate symptom score (IPSS), clinical symptoms, chronic pelvic pain syndrome (CPPS) and postoperative histopathology, 62 cases of BPH pathologically confirmed after transurethral plasma kinetic resection of the prostate (PKRP) were divided into a BPH group (n = 32) and a BPH + CP group (n = 30). The expressions of SIgA and alpha 1-AR in the prostate tissue were determined by immunohistochemistry and PT-PCR. RESULTS: Of the 62 cases, 30 were found to be BPH + CP, and the other 32 to be BPH. The expressions of SIgA and alpha1-AR were significantly higher in the BPH + CP than in the BPH group (0.380 8 +/- 0.144 3 vs 0.295 4 +/- 0.008 4 and 0.440 5 +/- 0.104 1 vs 0.383 2 +/- 0.013 6, P < 0.05). CONCLUSION: The upregulated expressions of SIgA and alpha1-AR expression in BPH complicated by CP suggest a certain association between CP and BPH, and that inflammation may be a pathogenic factor of BPH and correlate with its pathological development.


Assuntos
Imunoglobulina A Secretora/metabolismo , Próstata/metabolismo , Hiperplasia Prostática/metabolismo , Prostatite/metabolismo , Receptores Androgênicos/metabolismo , Idoso , Doença Crônica , Humanos , Masculino , Pessoa de Meia-Idade , Próstata/patologia , Hiperplasia Prostática/complicações , Hiperplasia Prostática/patologia , Prostatite/complicações , Prostatite/patologia
20.
Environ Sci Pollut Res Int ; 30(42): 95975-95987, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37558916

RESUMO

Polyethylene terephthalate-based glitters (PET glitters) are a potential source of primary microplastics in the environment. However, the bioeffects of PET glitters and the associated leachates remain largely unknown. In this study, we investigated the individual and combined toxicity of five colors (silver, black, red, green, and blue) of PET glitters and their corresponding leachates on the cellular responses of Desmodesmus sp. The results indicated that the photosynthesis of Desmodesmus sp. could be partly affected by PET glitters through the shading effect, but not that of growth. Conversely, the leachates of red and green PET glitters significantly inhibited the growth of the microalga, suggesting a higher risk associated with additives leached from these colors of PET glitters. Furthermore, the adverse effects of the co-occurrence of PET glitters and leachates were closely related to oxidative stress responses in the microalgal cells, along with a color effect, which could be mainly attributed to variations in the composition and abundance of toxic additives in different colors of PET glitters. Overall, our findings provide insights into the ecological risks posed by glitters in aquatic environments and emphasize the importance of considering color factors in assessing microplastics toxicity.


Assuntos
Poluentes Ambientais , Microalgas , Poluentes Químicos da Água , Microplásticos/toxicidade , Plásticos/toxicidade , Polietileno , Polietilenotereftalatos/toxicidade , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise
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