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1.
Chem Commun (Camb) ; 59(79): 11803-11806, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37721035

RESUMO

In this study, ruthenium-doped CoFe-based layered double hydroxides on Ni foam (CoFe-ZLDH/Ru@NF) were fabricated via an etching-precipitation strategy. The resultant CoFe-ZLDH/Ru@NF exhibited excellent activity, showing low overpotentials of 219.8 mV and 60.9 mV to reach the current density of 10 mA cm-2 for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), respectively. As a bifunctional electrocatalyst, it was assembled in an anion exchange membrane water electrolyser (AEMWE) unit, performing as an anode and cathode simultaneously, which only required a cell voltage of 2.33 V to accomplish the industrial level current density of 1 A cm-2 and operated steadily for over 12 h, making it promising for utilization in hydrogen production.

3.
Sci Rep ; 13(1): 4382, 2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36928374

RESUMO

The rising incidence rate of prostate cancer (PCa) worldwide has become a public health concern. PCa has a multifactorial etiology, and the link between human papillomavirus (HPV) and PCa has been widely investigated by numerous case-control studies. This age-matched, case-control study included 143 PCa patients and 135 benign prostatic hyperplasia (BPH) patients, with prostatic specimens testing negative for malignancy, as control. Study participants were recruited from four major hospitals in Taoyuan City, Taiwan, period 2018-2020, looking into HPV infection and other PCa risk factors, including dietary habits, family history, personal lifestyle, and sexual behavior. Multiple logistic regression analysis and forward stepwise selection analysis were conducted to identify potential risk factors for PCa. HPV DNA was found in 10 of the 143 PCa cases (7%) and 2 of the 135 BPH controls (1.5%) (OR = 6.02, 95% CI = 1.03-30.3, p = 0.046). This association was slightly significant, and furthermore, high risk HPV was not found to be associated with PCa. Higher body mass index (BMI) (OR = 1.15, 95% CI = 1.05-1.27, p = 0.003), more total meat consumption (OR = 2.74, 95% CI = 1.26-5.94, p = 0.011), exhibited association to PCa. However, PCa family history only presented a statistically significant difference by forward stepwise analysis (OR = 3.91, 95% CI = 1.17-13.12, p = 0.027). While much focus has been on the association between HPV and PCa, the results of this study indicate that more efforts should be directed towards investigating dietary habits, personal lifestyle and family history as factors for PCa. These results could serve as a basis for designing PCa prevention strategies.


Assuntos
Hiperplasia Prostática , Neoplasias da Próstata , Masculino , Humanos , Hiperplasia Prostática/epidemiologia , Estudos de Casos e Controles , Taiwan/epidemiologia , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/etiologia , Neoplasias da Próstata/patologia , Fatores de Risco , Papillomavirus Humano
4.
Huan Jing Ke Xue ; 43(11): 4888-4904, 2022 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-36437061

RESUMO

Since the late 1970s, marine ecotoxicology began to sprout and develop in China. Based on the principles of dose-response relationships, some marine organisms are used in toxicity tests to evaluate the impact of marine pollutants on marine organisms and marine ecosystems. At the early stage, marine ecotoxicological research mainly focused on the bioaccumulation, biomagnification, and biodegradation of traditional pollutants such as heavy metals, radioactive elements, organotin, petroleum hydrocarbons, and pesticides, as well as their toxic effects on survival, growth, and other physiological indicators. With the development of Chinese industry, marine pollution has become increasingly serious. In addition to the traditional marine pollutants, toxicological research has been conducted on emerging pollutants with potential risks to marine ecosystems, such as POPs, emerging organic pollutants, nanomaterials, and microplastics. Moreover, the species of marine organisms used in toxicity testing have become more diverse. The selection of testing organisms is essential for evaluating toxicity correctly. The toxicity tests should be conducted on a variety of organisms from different trophic levels to ensure the comprehensive understanding of the impact of pollutants on marine ecosystems. The major types of marine organisms used in the toxicity testing include marine alga, protozoa, rotifera, annelida, mollusc, echinoderma, arthropoda, cephalopoda, and marine fish, which have been used in the toxicological studies of various marine pollutants. The outcome results can serve as the scientific basis for the ecological risk assessment of marine pollutants and the establishment of seawater quality criteria. It should be noted that the sensitivity of different testing organisms to different types of pollutants is quite diverse. Therefore, in addition to conducting a battery of tests on a variety of species which play important roles in marine ecosystems, elucidating the toxic mechanisms in different species is also important for marine ecotoxicological studies. The application of the above-mentioned organisms in marine ecotoxicology research in recent years is briefly reviewed here. Particularly, the six commonly used marine model species (Skeletonema costatum, Euplotes vannus, oysters, sea urchins, Tigriopus japonicus, and Oryzias melastigma) used in toxicity testing are introduced in detail.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Animais , Ecotoxicologia , Ecossistema , Plásticos , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Testes de Toxicidade , Organismos Aquáticos
5.
Environ Sci Technol ; 56(18): 13179-13188, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36044019

RESUMO

Coastal systems experience diel fluctuation of pCO2 and cadmium (Cd) pollution; nevertheless, the effect of fluctuating pCO2 on Cd biotoxicity is poorly known. In this study, we initially performed the isotopically enriched organism bioassay to label Tigriopus japonicus with 113Cd (5 µg/L) to determine the Cd accumulation rate constant (kaccu) under ambient (400 µatm) and steadily (1000 µatm) and fluctuatingly elevated (1000 ± 600 µatm) pCO2 conditions for 48 h. Next, T. japonicus was interactively subjected to the above pCO2 exposures at Cd (control, 5, and 500 µg/L) treatments for 7 d. Biochemical and physiological responses for copepods were analyzed. The results showed that steadily increased pCO2 facilitated Cd bioaccumulation compared to ambient pCO2, and it was more under fluctuating acidification conditions. Despite compensatory reactions (e.g., increased energy production), Cd ultimately induced oxidative damage and apoptosis. Meanwhile, combined treatment exhibited higher toxicity (e.g., increased apoptosis) relative to Cd exposure, and even more if fluctuating acidification was considered. Intriguingly, fluctuating acidification inhibited Cd exclusion in Cd-treated copepods compared to steady acidification, linking to higher Cd kaccu and bioaccumulation. Collectively, CO2-driven acidification could aggravate Cd toxicity, providing a mechanistic understanding of the interaction between seawater acidification and Cd pollution in marine copepods.


Assuntos
Copépodes , Animais , Cádmio/toxicidade , Dióxido de Carbono , Concentração de Íons de Hidrogênio , Estresse Oxidativo , Água do Mar/química
6.
Toxins (Basel) ; 14(7)2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35878223

RESUMO

Gambierdiscus is a dinoflagellate genus widely distributed throughout tropical and subtropical regions. Some members of this genus can produce a group of potent polycyclic polyether neurotoxins responsible for ciguatera fish poisoning (CFP), one of the most significant food-borne illnesses associated with fish consumption. Ciguatoxins and maitotoxins, the two major toxins produced by Gambierdiscus, act on voltage-gated channels and TRPA1 receptors, consequently leading to poisoning and even death in both humans and animals. Over the past few decades, the occurrence and geographic distribution of CFP have undergone a significant expansion due to intensive anthropogenic activities and global climate change, which results in more human illness, a greater public health impact, and larger economic losses. The global spread of CFP has led to Gambierdiscus and its toxins being considered an environmental and human health concern worldwide. In this review, we seek to provide an overview of recent advances in the field of Gambierdiscus and its associated toxins based on the existing literature combined with re-analyses of current data. The taxonomy, phylogenetics, geographic distribution, environmental regulation, toxin detection method, toxin biosynthesis, and pharmacology and toxicology of Gambierdiscus are summarized and discussed. We also highlight future perspectives on Gambierdiscus and its associated toxins.


Assuntos
Ciguatera , Ciguatoxinas , Dinoflagellida , Doenças Transmitidas por Alimentos , Animais , Ciguatoxinas/análise , Ciguatoxinas/toxicidade , Dinoflagellida/genética , Peixes , Humanos
7.
Small ; 18(19): e2200303, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35388963

RESUMO

High-valence metal-doped multimetal (oxy)hydroxides outperform noble metal electrocatalysts for the oxygen evolution reaction (OER) owing to the modified energetics between 3d metals and high-valence dopants. However, the rational design of sufficient and subtle modulators is still challenging. With a multimetal layered double hydroxide (LDH) as the OER catalyst, this study introduces a series of operando high-valence dopants (Cr, Ru, Ce, and V), which can restrict the 3+ valence states in the LDH template to prevent phase separation and operando transfer to the >3+ valence states for sufficient electronic interaction during the OER process. Through density functional theory simulations, ultrathin Cr-doped NiFe (NiFeCr) LDH is synthesized with strong electronic interaction between Cr dopants and NiFe bimetallic sites, evidenced by X-ray absorption spectroscopy. The resulting NiFeCr-LDH catalyzes the OER with ultralow overpotentials of 189 and 284 mV, obtaining current densities of 10 and 1000 mA cm-2 , respectively. Further, a NiFeCr-LDH anode is coupled in the anion exchange membrane electrolyzers to promote alkaline water splitting and CO2 -to-CO electrolysis, which achieves low full cell voltages at high current densities.

8.
Front Microbiol ; 13: 749874, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35250917

RESUMO

The proteins present in the extracellular environment of cells, named the "exoproteome," are critical for microbial survival, growth, and interaction with their surroundings. However, little is known about microbial exoproteomes in natural marine environments. Here, we used a metaproteomic approach to characterize the exoprotein profiles (10 kDa-0.2 µm) throughout a water column in the South China Sea. Viruses, together with Alpha- and Gammaproteobacteria were the predominant contributors. However, the exoprotein-producing microbial communities varied with depth: SAR11 in the shallow waters, Pseudomonadales and Nitrososphaeria in the mesopelagic layer, and Alteromonadales, Rhizobiales, and Betaproteobacteria in the bathypelagic layer. Besides viral and unknown proteins, diverse transporters contributed substantially to the exoproteomes and varied vertically in their microbial origins, but presented similar patterns in their predicted substrate identities throughout the water column. Other microbial metabolic processes subject to vertical zonation included proteolysis, the oxidation of ammonia, nitrite and carbon monoxide, C1 metabolism, and the degradation of sulfur-containing dissolved organic matter (DOM). Our metaexoproteomic study provides insights into the depth-variable trends in the in situ ecological traits of the marine microbial community hidden in the non-cellular world, including nutrient cycling, niche partitioning and DOM remineralization.

9.
Environ Sci Technol ; 56(8): 5247-5255, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35352563

RESUMO

Diatoms, accounting for 40% of the marine primary production and 20% of global carbon dioxide fixation, are threatened by the ongoing ocean warming (OW). However, whether and how these ecologically important phytoplankton adapt to OW remains poorly unknown. Here, we experimentally examined the metabolic adaptation of a globally important diatom species Skeletonema dohrnii (S. dohrnii) to OW at two elevated temperatures (24 and 28 °C compared with 20 °C) under short-term (∼300 generations) and long-term (∼700 generations) selection. Both warming levels significantly increased the cell growth rate but decreased the chlorophyll a content. The contents of particulate organic carbon (POC) and particulate organic nitrogen (PON) decreased significantly initially (i.e., until 300 generations) at two temperature treatments but completely recovered after 700 generations of selection, suggesting that S. dohrnii ultimately developed thermal adaptation. Proteomic analysis demonstrated that elevated temperatures upregulated energy metabolism via glycolysis, tricarboxylic acid cycle, and fatty acid oxidation as well as nitrogen acquisition and utilization, which in turn reduced substance storage because of trade-off in the 300th generation, thus decreasing POC and PON. Interestingly, populations at both elevated temperatures exhibited significant proteome plasticity in the 700th generation, as primarily demonstrated by the increased lipid catabolism and glucose accumulation, accounting for the recovery of POC and PON. Changes occurring in cells at the 300th and 700th generations demonstrate that S. dohrnii can adapt to the projected OW, and readjusting the energy metabolism is an important adaptive strategy.


Assuntos
Diatomáceas , Clorofila A/metabolismo , Nitrogênio/metabolismo , Proteômica , Temperatura
10.
Bioorg Med Chem Lett ; 64: 128681, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35304224

RESUMO

We designed and synthesized 18 substituted indole derivatives containing a triazole scaffold as novel anti-influenza A virus candidates using a bio-isosteric and scaffold-hopping strategy from the lead compound 4-32-2. Most of the target compounds (eg: 6, 7a, 7d, 7f-j, 7l, 7m, 7o, 7q) exhibited potent anti-influenza A virus activity and low cytotoxicity in vitro. In particular, 7a exhibited the most potent anti-IAV activity (IC50: 1.34 ± 0.13 µM) with low cytotoxicity (CC50: > 100 µM), and high selectivity index (SI: > 74.63), which provides a new chemical scaffold for the development of novel anti-IAV drug.


Assuntos
Vírus da Influenza A , Triazóis , Antivirais/química , Desenho de Fármacos , Indóis/farmacologia , Relação Estrutura-Atividade , Triazóis/farmacologia
11.
Biomedicines ; 10(3)2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35327448

RESUMO

Prostate cancer (PCa) is the major cause of cancer-related death among aging men worldwide. Recent studies have suggested that calreticulin (CRT), a multifunctional chaperon protein, may play an important role in the regulation of PCa tumorigenesis and progression. However, the underlying mechanisms are still unclear. Integrin is an important regulator of cancer metastasis. Our previous study demonstrated that in J82 bladder cancer cells, CRT affects integrin activity through FUBP-1-FUT-1-dependent fucosylation, rather than directly affecting the expression of ß1-integrin itself. However, whether this regulatory mechanism is conserved among different cell types remains to be determined. Herein, we attempted to determine the effects of CRT on ß1-integrin in human prostate cancer PC-3 cells. CRT expression was suppressed in PC-3 cells through siRNA treatment, and then the expression levels of FUT-1 and ß1-integrin were monitored through RT-PCR. We found that knockdown of CRT expression in PC-3 cells significantly affected the expression of ß1-integrin itself. In addition, the lower expression level of ß1-integrin was due to affecting the mRNA stability. In contrast, FUT-1 expression level was not affected by knockdown of CRT. These results strongly suggested that CRT regulates cellular behavior differently in different cell types. We further confirmed that CRT directly binds to the 3'UTR of ß1-integrin mRNA by EMSA and therefore affects its stability. The suppression of CRT expression also affects PC-3 cell adhesion to type I collagen substrate. In addition, the levels of total and activated ß1-integrin expressed on cell surface were both significantly suppressed by CRT knockdown. Furthermore, the intracellular distribution of ß1-integrin was also affected by lowering the expression of CRT. This change in distribution is not lysosomal nor proteosomal pathway-dependent. The treatment of fucosydase significantly affected the activation of surface ß1-integrin, which is conserved among different cell types. These results suggested that CRT affects the expression of ß1-integrin through distinct regulatory mechanisms.

12.
Bioorg Med Chem Lett ; 41: 127980, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33766773

RESUMO

Infections caused by antibiotic resistant bacteria are a major health concern throughout the world. It is well known that PFK-158 can enhance the antibacterial effect of polymyxin, but its own anti-bactericidal effect is rarely discussed. In order to investigate the anti-bactericidal effect of PFK-158 and its derivatives, PFK-158 and 35 derivatives were designed, synthesized, and evaluated for their antibacterial activities. Compounds A1, A3, A14, A15 and B6 exhibited potent antibacterial effect against both clinical drug sensitive and resistant Gram-positive bacteria, and they are 2-8 folds more potent than levofloxacin against Methicillin-resistant staphylococcus epidermidis (MRSE). A significant synergistic effect of these compounds and polymyxin against drug-resistant Gram-negative bacteria, which is similar to PFK-158 was also observed. The result can provided a new and broader prospect for the development of new medicine against drug-resistant bacteria.


Assuntos
Antibacterianos/farmacologia , Enterococcus/efeitos dos fármacos , Resistência a Meticilina/efeitos dos fármacos , Piridinas/farmacologia , Quinolinas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Resistência a Vancomicina/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Relação Dose-Resposta a Droga , Desenho de Fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Piridinas/síntese química , Piridinas/química , Quinolinas/síntese química , Quinolinas/química , Relação Estrutura-Atividade
13.
Med Dosim ; 45(3): 271-277, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32122694

RESUMO

PURPOSE: To compare the dosimetric characteristics of helical tomotherapy (HT), volumetric-modulated arc therapy (VMAT), intensity-modulated radiotherapy (IMRT), and tangential field-in-field technique (FIF) for the treatment of synchronous bilateral breast cancer (SBBC). METHODS AND MATERIALS: Ten patients with early-stage unilateral breast cancer were selected for simulating the patients with SBBC in this retrospective analysis. Treatment plans with HT, VMAT, IMRT, and FIF were generated for each patient with a total dose of 50.4 Gy in 28 fractions to the target. Plan quality, namely conformity index (CI), homogeneity index (HI), dose-volume statistics of organs at risk (OARs), and beam-on time (BOT), were evaluated. RESULTS: HT plans showed a lower mean heart dose (3.53 ± 0.31Gy) compared with the other plans (VMAT = 5.6 ± 1.36 Gy, IMRT = 3.80 ± 0.76 Gy, and FIF = 4.84 ± 2.13 Gy). Moreover, HT plans showed a significantly lower mean lung dose (p < 0.01) compared with the other plans: mean right lung doses were 6.81 ± 0.67, 10.32 ± 1.04, 9.07 ± 1.21, and 10.03 ± 1.22 Gy and mean left lung doses were 6.33 ± 0.87, 8.82 ± 0.91, 7.84 ± 1.07, and 8.64 ± 0.99 Gy for HT, VMAT, IMRT, and FIF plans, respectively. The mean dose to the left anterior descending artery was significantly lower in HT plans (p < 0.01) than in the other plans: HT = 19.41 ± 0.51 Gy, VMAT = 25.77 ± 7.23 Gy, IMRT = 27.87 ± 6.48 Gy, and FIF = 30.95 ± 10.17 Gy. FIF plans showed a worse CI and HI compared with the other plans. VMAT plans showed shorter BOT (average, 3.9 ± 0.2 minutes) than did HT (average, 11.0 ± 3.0 minutes), IMRT (average, 6.1 ± 0.5 minutes), and FIF (average, 4.6 ± 0.7 minutes) plans. CONCLUSIONS: In a dosimetric comparison for SBBC, HT provided the most favorable dose sparing of OARs. However, HT with longer BOT may increase patient discomfort and treatment uncertainty. VMAT enabled shorter BOT with acceptable doses to OARs and had a better CI than did FIF and IMRT.


Assuntos
Neoplasias da Mama/radioterapia , Neoplasias Primárias Múltiplas/radioterapia , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Neoplasias da Mama/diagnóstico por imagem , Feminino , Coração , Humanos , Pulmão , Neoplasias Primárias Múltiplas/diagnóstico por imagem , Órgãos em Risco , Radiometria , Estudos Retrospectivos , Tomografia Computadorizada Espiral
14.
J Hazard Mater ; 386: 121951, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31895998

RESUMO

To clarify the environmental behaviour and bioactivity of epoxiconazole enantiomers, an integrated assessment has been done. The degradation in soil, water, and river-sediments were studied. The toxicity to Chlorella vulgaris and Daphnia magna was also examined. The bioactivity to plant-pathogens and molecular docking to CYP51 were investigated. The obtained results showed that the half-lives of R,S-(+)- and S,R-(-)-epoxiconazole were 38.8 and 21.2 days in Jiangsu soil, 43.2 and 22.7 days in Jiangxi soil, 29.1 and 21.3 days in Jilin soil, 43.5 and 32.7 days in anaerobic Jilin soil, 12.3 and 10.1 days in river sediments, and 33.2 and 9.3 days in river water, respectively. Maximum EF was 0.36 in Yangzi-river water. No enantioselective degradation was found in sterilized conditions. The EC50 to C. vulgaris after 48 h was 27.78 mg L-1, and 18.93 mg L-1 for R,S-(+)-, and S,R-(-)-epoxiconazole, respectively. The LC50 to D. magna was 4.16 mg L-1, and 8.49 mg L-1 for R,S-(+)-, and S,R-(-)-epoxiconazole, respectively. R,S-(+)-epoxiconazole bioactivity was 1.3-7.25 times higher than S,R-(-)-epoxiconazole. In conclusion, R,S-(+)- has higher bioactivity and higher environmental toxicity. In opposite, S,R-(-)- has lower environmental toxicity and lower bioactivity. R,S-(+)-epoxiconazole use is recommended with lower concentrations, which is appropriate for environment safety.


Assuntos
Poluentes Ambientais/toxicidade , Compostos de Epóxi/toxicidade , Fungicidas Industriais/toxicidade , Sedimentos Geológicos/química , Rios/química , Solo/química , Triazóis/toxicidade , Aerobiose , Anaerobiose , Animais , Biodegradação Ambiental , Chlorella vulgaris/efeitos dos fármacos , Chlorella vulgaris/crescimento & desenvolvimento , Sistema Enzimático do Citocromo P-450/química , Daphnia/efeitos dos fármacos , Daphnia/crescimento & desenvolvimento , Poluentes Ambientais/análise , Poluentes Ambientais/química , Compostos de Epóxi/análise , Compostos de Epóxi/química , Proteínas Fúngicas/química , Fungicidas Industriais/análise , Fungicidas Industriais/química , Dose Letal Mediana , Simulação de Acoplamento Molecular , Estereoisomerismo , Testes de Toxicidade Aguda , Triazóis/análise , Triazóis/química
15.
Bioorg Med Chem Lett ; 28(23-24): 3816-3821, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30342958

RESUMO

MMP-2/MMP-8 is established as one of the most important metalloenzymes for targeting cancer. A series of dihydropyrazothiazole derivatives (E1-E18) bearing a salicylaldehyde group linked to Pyrazole ring were designed, synthesized, and evaluated for their pharmacological activity as MMP-2/MMP-8 inhibitors. Among them, compound E17 exhibited most potent inhibitory activity (IC50 = 2.80 µM for MMP-2 and IC50 = 5.6 µM for MMP-8), compared to the positive drug CMT-1 (IC50 = 1.29 µM). Compounds (E1-E18) were scrutinized by CoMFA and CoMSIA techniques of Three-dimensional quant. structure-activity relationship (3D-QSAR), as well as a docking simulation. Moreover, treatment with compound E4 could induce MCF-7 cell apoptosis. Overall, the biological profile of E1-E18 may provide a research basis for the development of new agents against cancer.


Assuntos
Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 8 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz/química , Inibidores de Metaloproteinases de Matriz/farmacologia , Tiazóis/química , Tiazóis/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Desenho de Fármacos , Humanos , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Pirazóis/química , Pirazóis/farmacologia , Relação Quantitativa Estrutura-Atividade
16.
Environ Microbiol ; 20(2): 477-491, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28925544

RESUMO

Viral concentrates (VCs), containing bioinformative DNA and proteins, have been used to study viral diversity, viral metagenomics and virus-host interactions in natural ecosystems. Besides viruses, VCs also contain many noncellular biological components including diverse functional proteins. Here, we used a shotgun proteomic approach to characterize the proteins of VCs collected from the oligotrophic deep chlorophyll maximum (DCM) of the South China Sea. Proteins of viruses infecting picophytoplankton, that is, cyanobacteria and prasinophytes, and heterotrophic bacterioplankton, such as SAR11 and SAR116, dominated the viral proteome. Almost no proteins from RNA viruses or known gene transfer agents were detected, suggesting that they were not abundant at the sampling site. Remarkably, nonviral proteins made up about two thirds of VC proteins, including overwhelmingly abundant periplasmic transporters for nutrient acquisition and proteins for diverse cellular processes, that is, translation, energy metabolism and one carbon metabolism. Interestingly, three 56 kDa selenium-binding proteins putatively involved in peroxide reduction from gammaproteobacteria were abundant in the VCs, suggesting active removal of peroxide compounds at DCM. Our study demonstrated that metaproteomics provides a valuable avenue to explore the diversity and structure of the viral community and also the pivotal biological functions affiliated with microbes in the natural environment.


Assuntos
Proteínas Periplásmicas/isolamento & purificação , Água do Mar/virologia , Proteínas Virais/isolamento & purificação , Bactérias/virologia , Proteínas de Bactérias/isolamento & purificação , Clorofila , Cianobactérias/virologia , Gammaproteobacteria/metabolismo , Oceanos e Mares , Plâncton/virologia , Proteômica , Água do Mar/microbiologia , Proteínas de Ligação a Selênio/isolamento & purificação
17.
Chem Commun (Camb) ; 53(28): 3941-3944, 2017 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-28300246

RESUMO

Tunable electrochemical biosensors based on analogous Zr-MOFs were developed for protein detection, the performances of which rely on the pore sizes and surroundings of the MOFs that show diverse binding behaviors to aptamers and then the targeted proteins. The optimized Zr-MOF-based sensor has high selectivity to lysozyme in a wide concentration range and a low detection limit of 3.6 pg mL-1, with good repeatability, stability, and applicability in real samples. This work will establish a new platform for biosensing and extend the application scope of MOF materials.


Assuntos
Muramidase/análise , Compostos Organometálicos/química , Zircônio/química , Técnicas Biossensoriais , Técnicas Eletroquímicas , Modelos Moleculares , Muramidase/metabolismo , Tamanho da Partícula
18.
Environ Microbiol ; 17(10): 3976-91, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26014042

RESUMO

Diatoms are a major phytoplankton group causing extensive blooms in the ocean. However, little is known about the intracellular biological processes occurring during the blooming period. This study compared the protein profiles of field-collected and laboratory-cultured blooming cells of Skeletonema costatum, and identified highly and differentially expressed proteins using the shotgun proteomic approach. A total of 1372 proteins were confidently identified with two or more peptides. Among them, 222 and 311 proteins were unique to the laboratory and field samples respectively. Proteins involved in photosynthesis, translation, nucleosome assembly, carbohydrate and energy metabolism dominated the protein profiles in both samples. However, different features of specific proteins were also found: proteins participated in light harvesting, photosynthetic pigment biosynthesis, photoprotection, cell division and redox homeostasis were highly detected in the field sample, whereas proteins involved in translation, amino acid and protein metabolic processes, and nitrogen and carbon assimilation presented high detection rates in the laboratory sample. ATP synthase cf1 subunit beta and light harvest complex protein were the most abundant protein in the laboratory and field samples respectively. These results indicated that S. costatum had evolved adaptive mechanisms to the changing environment, and integrating field and laboratory proteomic data should provide comprehensive understanding of bloom mechanisms.


Assuntos
Metabolismo dos Carboidratos/fisiologia , Diatomáceas/genética , Diatomáceas/metabolismo , Metabolismo Energético/fisiologia , Proteínas/genética , Proteômica/métodos , Aminoácidos/metabolismo , Carbono/metabolismo , Nitrogênio/metabolismo , Fotossíntese/genética , Fitoplâncton/metabolismo
19.
J Hazard Mater ; 284: 65-72, 2015 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-25463219

RESUMO

The enantioselective bioactivity, acute toxicity and stereoselective degradation of the chiral triazole fungicide flutriafol in vegetables were investigated for the first time using the (R)-, (S)- and rac-flutriafol. The order of the bioactivity against five target pathogens (Rhizoctonia solani, Alternaria solani, Pyricularia grisea, Gibberella zeae, Botrytis cinerea) was found to be (R)-flutriafol>rac-flutriafol>(S)-flutriafol. The fungicidal activity of (R)-flutriafol was 1.49-6.23 times higher than that of (S)-flutriafol. The (R)-flutriafol also showed 2.17-3.52 times higher acute toxicity to Eisenia fetida and Scenedesmus obliquus than (S)-flutriafol. The stereoselective degradation of flutriafol in tomato showed that the active (R)-flutriafol degraded faster, resulting in an enrichment of inactive (S)-form, and the half-lives were 9.23 d and 10.18 d, respectively. Inversely, the (S)-flutriafol, with a half-life of 4.76 d, was preferentially degraded in cucumber. In conclusion, the systemic assessments of the triazole fungicide flutriafol stereoisomers on the enantioselective bioactivity, acute toxicity and environmental behavior may have implications for better environmental and ecological risk assessment.


Assuntos
Fungicidas Industriais/química , Fungicidas Industriais/toxicidade , Triazóis/química , Alternaria , Animais , Botrytis , Calibragem , Cromatografia Líquida de Alta Pressão , Cucumis sativus , Ecologia , Gibberella , Solanum lycopersicum , Oligoquetos , Rhizoctonia , Medição de Risco , Estereoisomerismo , Triazóis/toxicidade , Verduras
20.
Pest Manag Sci ; 71(4): 607-15, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25228142

RESUMO

BACKGROUND: Application of a matrix-immobilised target enzyme for screening inhibitors is widely used in drug development, but there are few studies in insecticide discovery. In this paper, an economical and effective immobilised acetylcholinesterase (AChE) column was prepared using the sol-gel embedment method, which was further combined with high-performance liquid chromatography for screening the AChE inhibitors and insecticidal compounds from complex natural products. RESULTS: AChE inhibitory constituents magnolol and honokiol were isolated from the ethanol extract of Magnolia officinalis, with IC50 values of 0.069 and 0.057 mM respectively. In an in vivo bioassay, magnolol and honokiol showed insecticidal activity against Nilaparvata lugens, with LC50 values of 0.324 and 0.137 mM, which are comparable with that of commonly used insecticide chlorpyrifos (0.233 mM). Moreover, molecular docking was carried out against a homology model of N. lugens AChE. The complexes showed that magnolol and honokiol placed themselves nicely into the active site of the enzyme and exhibited an interaction energy that was in accordance with our activity profile data. CONCLUSION: These results demonstrate that magnolol and honokiol have great applied potential to be developed as natural insecticides, and an immobilised AChE column is very useful as a rapid screening tool for target enzymes towards potent inhibitors.


Assuntos
Alcaloides/farmacologia , Compostos de Bifenilo/farmacologia , Cromatografia Líquida de Alta Pressão/instrumentação , Hemípteros/efeitos dos fármacos , Inseticidas/farmacologia , Lignanas/farmacologia , Magnolia/química , Sesquiterpenos/farmacologia , Acetilcolinesterase/metabolismo , Animais , Inibidores da Colinesterase/metabolismo , Feminino , Extratos Vegetais/farmacologia
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