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1.
Bioorg Chem ; 130: 106223, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36356372

RESUMO

Eight hybrids of amantadine (ATD) with a natural modulator gardenamide A (GA) via an alkylene carbonyl bridge or alkylene bridge have been designed and synthesized. Evaluated by electrophysiological assay, compound 5b was confirmed an enhanced NMDAR antagonist compared to ATD with IC50 value of 10.2 ± 1.2 µM. 5b has been demonstrated to reverse the damages of behavioral performance, the loss of dopaminergic neurons, the reduction of TH positive, and the increase of α-synuclein in both MPTP-treated mice and zebrafish models. In both ethological and ecological experiments, the activity of 5b was confirmed better than ATD or ATD/GA combination, and was almost equal to the positive selegiline. In vivo and in vitro, 5b is shown to reverse the ascend of NR1 and i-NOS levels. This candidate was also demonstrated the activity to down-regulated MPTP-increased Ca2+ influx in SH-SY5Y cells in a steep and sharp mode. It is displayed that 5b exerts neuroprotective effect partly by activating the PI3K/Akt signaling pathway. Taken all together, our data support that 5b is a more promising agent against PD than ATD.


Assuntos
N-Metilaspartato , Neuroblastoma , Humanos , Camundongos , Animais , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Fosfatidilinositol 3-Quinases/metabolismo , Peixe-Zebra/metabolismo , Camundongos Endogâmicos C57BL , Amantadina/farmacologia
2.
Bioorg Chem ; 120: 105624, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35065464

RESUMO

A series of 5f-based new compounds has been designed and synthesized. In vitro screening demonstrated that the binding affinity and selectivity on aldose reductase (AR) were positively correlated with its antioxidation capacity. Compound 6d was verified the most active candidate, where its IC50, selective index (SI), and EC50 value was 22.3 ± 1.6 nM, 236.2, and 8.7 µM respectively. 6d was confirmed as both an excellent antioxidant and aldose reductase inhibitor (ARI). It was identified as a mixed type ARI with Ki and Kis values of 23.94 and 1.20 nM. When evaluated by a high-glucose impaired chicken embryo model, it was found that 6d attenuated the incidence of neural tube defect (NTD) and death rate in a dose-dependent manner. It significantly improved the hyperglycemia-induced abnormalities of body weight and morphology of chicken embryos. 6d reversed the hyperglycemia-raised AR activity, sorbitol accumulation, reactive oxygen species (ROS) and malondialdehyde (MDA) levels. It restored the high-glucose-reduced Pax3 protein expression. At the same dose (0.5 µM), 6d showed better effects than 5f in all the above detections. By the way, 6d did not affect hyperglycemia-elevated aldehyde reductase (ALR1) activity. This evidence together with its kinetic properties, implicated that 6d is a high selective ARI without the suspicion of promiscuity. 6d was proved here an effective agent to treat diabetic peripheral neuropathy (DPN). Whether 6d has potential to treat other types of diabetic complications (DC) needs to be further investigation.


Assuntos
Aldeído Redutase , Hiperglicemia , Animais , Antioxidantes/farmacologia , Embrião de Galinha , Inibidores Enzimáticos/uso terapêutico , Glucose , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes
3.
J Air Waste Manag Assoc ; 65(12): 1434-45, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26453185

RESUMO

UNLABELLED: Industry-standard Tedlar bags for odor sample collection from confined animal feeding operations (CAFOs) have been challenged by the evidence of volatile organic compound (VOC) losses and background interferences. Novel impermeable aluminum foil with a thin layer of fluorinated ethylene propylene (FEP) film on the surface that is in contact with a gas sample was developed to address this challenge. In this research, Tedlar and metallized FEP bags were compared for (a) recoveries of four characteristic CAFO odorous VOCs (ethyl mercaptan, butyric acid, isovaleric acid and p-cresol) after 30 min and 24 hr sample storage time and for (b) chemical background interferences. All air sampling and analyses were performed with solid-phase microextraction (SPME) followed by gas chromatography-mass spectroscopy (GC-MS). Mean target gas sample recoveries from metallized FEP bags were 25.9% and 28.0% higher than those in Tedlar bags, for 30 min and 24 hr, respectively. Metallized FEP bags demonstrated the highest p-cresol recoveries after 30-min and 24-hr storage, 96.1±44.5% and 44.8±10.2%, respectively, among different types of sampling bags reported in previous studies. However, a higher variability was observed for p-cresol recovery with metallized FEP bags. A 0% recovery of ethyl mercaptan was observed with Tedlar bags after 24-hr storage, whereas an 85.7±7.4% recovery was achieved with metallized FEP bags. Recoveries of butyric and isovaleric acids were similar for both bag types. Two major impurities in Tedlar bags' background were identified as N,N-dimethylacetamide and phenol, while backgrounds of metallized FEP bags were significantly cleaner. Reusability of metallized FEP bags was tested. IMPLICATIONS: Caution is advised when using polymeric materials for storage of livestock-relevant odorous volatile organic compounds. The odorants loss with storage time confirmed that long-term storage in whole-air form is ill advised. A focused short-term odor sample containment should be biased toward the most inert material available relative to the highest impact target odorant. Metallized FEP was identified as such a material to p-cresol as the highest impact odorant from confined animal feeding operations. Metallized FEP bags have much cleaner background than commercial Tedlar bags do. Significantly higher recoveries of methyl mercaptan and p-cresol were also observed with metallized FEP bags.


Assuntos
Alcenos/química , Gases/química , Odorantes/análise , Polímeros/química , Compostos Orgânicos Voláteis/química , Adsorção , Poluentes Atmosféricos/análise , Animais , Animais Domésticos , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Fatores de Tempo
4.
Food Chem ; 110(2): 399-405, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26049232

RESUMO

Chiral pesticide enantiomers often show different bioactivity and residual toxicity, but this property is usually ignored when evaluating the environmental risk and public safety. In this study, a convenient and precise chiral method was developed and validated for measuring fipronil enantiomers in Chinese cabbage (Brassica pekinensis) based on a high-performance liquid chromatography (HPLC) using (R,R) Whelk-O 1 column. Then the proposed method was successfully applied to the study of enantioselective degradation of fipronil in Chinese cabbage under field conditions. The results showed that the degradation of the two enantiomers in Chinese cabbage was proved to be enantioselective and followed pseudo first-order kinetics (R(2)⩾0.98). The (R)-enantiomer degraded faster than the (S)-enantiomer, resulting in the relative enrichment of (S)-enantiomer in residue. The detected metabolites MB46513 (desthio), MB45950 (sulfide) and MB46136 (sulfone) by GC-MS suggested that degradation was mainly contributed by oxidization, reduction and photodegradation. Due to the more insecticide activity and lower mammalian toxicity of S-form, the higher concentration of S-fipronil may result in higher activity in crop protection and lower risk to environment and human beings compared to the recemate. This result should be considered in future environmental risk and food safety evaluation.

5.
Front Microbiol ; 9: 2821, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30519228

RESUMO

The benthic boundary layer (BBL) is the part of the water column that is situated near to the sediment surface, where active oceanic biogeochemical cycling occurs. Archaea play an important role in mediating this cycling, however, their composition and diversity in the BBL remain largely unknown. We investigated the community composition and abundance of both particle-attached (PA) and free-living (FL) archaea in the BBL on the slopes of the Mariana Trench using Illumina sequencing and quantitative PCR (qPCR), at both the DNA and RNA levels. Our results showed that Thaumarchaeota (>90%) and Woesearchaeota (1-10%) dominated in all the BBL samples, and that the former was composed mainly of Marine Group I (MGI). A clear separation of PA and FL samples was observed, and they showed a high level of similarity to the subsurface sediments and the water column, respectively. No significant differences were detected in the archaeal communities located in the southern and northern slopes of the Mariana Trench, or between the levels of DNA and RNA. However, lower RNA/DNA ratios (estimated by qPCR) were found in the PA samples than in the FL samples, indicating higher transcriptional activities in the FL fractions. A distinct archaeal community structure was found in the middle of the trench when compared with samples collected at the same depth at other stations along the trench slopes. This indicates that a dynamic deep current might affect the distribution of organic matter on the slopes. Our study provides direct information regarding the archaeal communities in the BBL of the Mariana Trench. We suggest that this might promote further exploration of the ecological roles and microbial processes of such communities located in deep-sea ecosystems.

6.
Sci Rep ; 8(1): 15357, 2018 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-30337591

RESUMO

Picoeukaryotes play prominent roles in the biogeochemical cycles in marine ecosystems. However, their molecular diversity studies have been confined in marine surface waters or shallow coastal sediments. Here, we investigated the diversity and metabolic activity of picoeukaryotic communities at depths ranging from the surface to the abyssopelagic zone in the western Pacific Ocean above the north and south slopes of the Mariana Trench. This was achieved by amplifying and sequencing the V4 region of both 18S ribosomal DNA and cDNA using Illumina HiSeq sequencing. Our study revealed: (1) Four super-groups (i.e., Alveolata, Opisthokonta, Rhizaria and Stramenopiles) dominated the picoeukaryote assemblages through the water column, although they accounted for different proportions at DNA and cDNA levels. Our data expand the deep-sea assemblages from current bathypelagic to abyssopelagic zones. (2) Using the cDNA-DNA ratio as a proxy of relative metabolic activity, the highest activity for most subgroups was usually found in the mesopelagic zone; and (3) Population shift along the vertical scale was more prominent than that on the horizontal differences, which might be explained by the sharp physicochemical gradients along the water depths. Overall, our study provides a better understanding of the diversity and metabolic activity of picoeukaryotes in water columns of the deep ocean in response to varying environmental conditions.


Assuntos
Alveolados , Biodiversidade , Biota , Células Eucarióticas , Rhizaria , Estramenópilas , Alveolados/classificação , Alveolados/genética , Alveolados/crescimento & desenvolvimento , Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Organismos Aquáticos/crescimento & desenvolvimento , Biota/fisiologia , Demografia , Ecossistema , Células Eucarióticas/classificação , Oceano Pacífico , Filogenia , RNA Ribossômico 18S/genética , Rhizaria/classificação , Rhizaria/genética , Rhizaria/crescimento & desenvolvimento , Água do Mar/química , Análise de Sequência de DNA , Estramenópilas/classificação , Estramenópilas/genética , Estramenópilas/crescimento & desenvolvimento
7.
J Chromatogr A ; 1414: 31-40, 2015 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-26456221

RESUMO

Aerial emissions of odorous volatile organic compounds (VOCs) are an important nuisance factor from livestock production systems. Reliable air sampling and analysis methods are needed to develop and test odor mitigation technologies. Quantification of VOCs responsible for livestock odor remains an analytical challenge due to physicochemical properties of VOCs and the requirement for low detection thresholds. A new air sampling and analysis method was developed for testing of odor/VOCs mitigation in simulated livestock emissions system. A flow-through standard gas generating system simulating odorous VOCs in livestock barn emissions was built on laboratory scale and tested to continuously generate ten odorous VOCs commonly defining livestock odor. Standard VOCs included sulfur VOCs (S-VOCs), volatile fatty acids (VFAs), and p-cresol. Solid-phase microextraction (SPME) was optimized for sampling of diluted odorous gas mixtures in the moving air followed by gas chromatography-mass spectrometry (GC-MS) analysis. CAR/PDMS 85µm fiber was shown to have the best sensitivity for the target odorous VOCs. A practical 5-min sampling time was selected to ensure optimal extraction of VFAs and p-cresol, as well as minimum displacement of S-VOCs. Method detection limits ranged from 0.39 to 2.64ppbv for S-VOCs, 0.23 to 0.77ppbv for VFAs, and 0.31ppbv for p-cresol. The method developed was applied to quantify VOCs and odorous VOC mitigation with UV light treatment. The measured concentrations ranged from 20.1 to 815ppbv for S-VOCs, 10.3 to 315ppbv for VFAs, and 4.73 to 417ppbv for p-cresol. Relative standard deviations between replicates ranged from 0.67% to 12.9%, 0.50% to 11.4%, 0.83% to 5.14% for S-VOCs, VFAs, and p-cresol, respectively. This research shows that a simple manual SPME sampler could be used successfully for quantification of important classes of odorous VOCs at concentrations relevant for real aerial emissions from livestock operations.


Assuntos
Gado , Odorantes , Compostos Orgânicos Voláteis/análise , Animais , Cresóis/análise , Ácidos Graxos Voláteis/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Microextração em Fase Sólida/métodos
8.
J Agric Food Chem ; 61(34): 8198-206, 2013 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-23899009

RESUMO

Commercial manufacture of fruit leathers (FL) usually results in a portion of the product that is out of specification. The disposition of this material poses special challenges in the food industry. Because the material remains edible and contains valuable ingredients (fruit pulp, sugars, acidulates, etc.), an ideal solution would be to recover this material for product rework. A key practical obstacle to such recovery is that compositing of differently colored wastes results in an unsalable gray product. Therefore, a safe and scalable method for decolorization of FL prior to product rework is needed. This research introduces a novel approach utilizing ozonation for color removal. To explore the use of ozonation as a decolorization step, we first applied it to simple solutions of the commonly used food colorants 2-naphthalenesulfonic acid (Red 40), tartrazine (Yellow 5), and erioglaucine (Blue 1). Decolorization was measured by UV/vis spectrometry at visible wavelengths and with a Hunter colorimeter. Volatile and semivolatile byproducts from ozone-based colorant decomposition were identified and quantified with solid phase microextraction coupled with gas chromatography-mass spectrometry (SPME-GC-MS). Removal of Yellow 5, Red 40 and Blue 1 of about 65%, 80%, and 90%, respectively, was accomplished with 70 g of ozone applied per 1 kg of redissolved and resuspended FL. Carbonyl compounds were identified as major byproducts from ozone-induced decomposition of the food colorants. A conservative risk assessment based on quantification results and published toxicity information of potentially toxic byproducts, determined that ozone-based decolorization of FL before recycling is acceptable from a safety standpoint. A preliminary cost estimate based on recycling of 1000 tons of FL annually suggests a potential of $275,000 annual profit from this practice at one production facility alone.


Assuntos
Doces/análise , Corantes de Alimentos/química , Resíduos Industriais/análise , Ozônio/química , Reciclagem/métodos , Corantes de Alimentos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Microextração em Fase Sólida
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