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1.
Microbiol Resour Announc ; : e0010724, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38651915

RESUMO

Microbes play a significant role in the cleanup of xenobiotic contaminants. Based on metagenomes derived from long-term enrichment cultures grown on xenobiotic solvents, we report 166 metagenome-assembled genomes, of which 137 are predicted to be more than 90% complete. These genomes broaden the representation of xenobiotic degraders.

2.
Drug Des Devel Ther ; 18: 767-780, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495631

RESUMO

Purpose: Pulmonary arterial hypertension (PAH) is a devastating disease with little effective treatment. The proliferation of pulmonary artery smooth muscle cells (PASMCs) induced by the nuclear factor-κB (NF-κB) signaling activation plays a pivotal role in the pathogenesis of PAH. Forsythoside B (FTS•B) possesses inhibitory effect on NF-κB signaling pathway. The present study aims to explore the effects and mechanisms of FTS•B in PAH. Methods: Sprague-Dawley rats received monocrotaline (MCT) intraperitoneal injection to establish PAH model, and FTS•B was co-treated after MCT injection. Right ventricular hypertrophy and pulmonary artery pressure were measured by echocardiography and right heart catheterization, respectively. Histological alterations were detected by H&E staining and immunohistochemistry. FTS•B's role in PASMC proliferation and migration were evaluated by CCK-8 and wound healing assay. To investigate the underlying mechanisms, Western blotting, immunofluorescence staining and ELISA were conducted. The NF-κB activator PMA was used to investigate the role of NF-κB in FTS•B's protective effects against PAH. Results: FTS•B markedly alleviated MCT-induced vascular remodeling and pulmonary artery pressure, and improved right ventricular hypertrophy and survival. FTS•B also reversed PDGF-BB-induced PASMC proliferation and migration, decreased PCNA and CyclinD1 expression in vitro. The elevated levels of IL-1ß and IL-6 caused by MCT were decreased by FTS•B. Mechanistically, MCT-triggered phosphorylation of p65, IκBα, IKKα and IKKß was blunted by FTS•B. FTS•B also reversed MCT-induced nuclear translocation of p65. However, all these protective effects were blocked by PMA-mediated NF-κB activation. Conclusion: FTS•B effectively attenuates PAH by suppressing the NF-κB signaling pathway to attenuate vascular remodeling. FTS•B might be a promising drug candidate with clinical translational potential for the treatment of PAH.


Assuntos
Ácidos Cafeicos , Glucosídeos , Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Ratos , Animais , NF-kappa B/metabolismo , Monocrotalina/efeitos adversos , Ratos Sprague-Dawley , Remodelação Vascular , Hipertrofia Ventricular Direita/metabolismo , Hipertrofia Ventricular Direita/patologia , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/tratamento farmacológico , Transdução de Sinais
4.
Animals (Basel) ; 13(17)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37685009

RESUMO

CuSO4 is the most commonly used feed additive in pig production at present, but long-term ingestion of excessive copper would lead to chronic copper toxicity. High copper could reduce the reproductive efficiency of sows and seriously affect the development of the pig industry. Quercetin (QUE), a powerful antioxidant, reduces toxicity of a number of heavy metals. Porcine granulosa cells (pGCs) are crucial to the fate of follicle development. The present study found that high concentrations of CuSO4 induced ROS production, which resulted in decreased mRNA expression of antioxidant-related genes GPX4, CAT, and SOD2 and increased mRNA expression of SOD1, TRX, and HO-1. The protein expression of antioxidant enzymes SOD2 and HO-1 decreased. Moreover, the concentration of MDA increased, the activity of CAT decreased, and the content of GSH decreased. After high copper treatment, the mitochondrial membrane potential (MMP) was decreased and the morphological structure was changed. However, the combined treatment with Quercetin (QUE) reversed these changes, and the level of cellular oxidative stress decreased. Therefore, we conclude that high copper has oxidative toxicity to pGCs, and QUE could remove the ROS induced by high copper, protect mitochondria from oxidative stress damage, and improve the function of pGCs.

5.
Materials (Basel) ; 16(14)2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37512263

RESUMO

The ultra-fast laser heating process of nano-films is characterized by an ultra-short duration and ultra-small space size, in which the classical Fourier law based on the hypothesis of local equilibrium is no longer applicable. Based on the Cattaneo-Vernotte (CV) model and the dual-phase-lag (DPL) model, the two-dimensional analytical solutions of heat conduction in nano-films under ultra-fast laser are obtained using the integral transformation method. The results show that there is a thermal wave phenomenon inside the film, which becomes increasingly evident as the elapse of the lag time of the temperature gradient. Moreover, the wave amplitude in the vertical direction is much larger than that in the horizontal direction of the nano-film. By comparing the numerical result of the two models, it is found that the temperature distribution inside the nano-film based on the DPL model is gentler than that of the CV model. Additionally, the temperature distribution in the two-dimensional solution is lower than that in the one-dimensional solution under the same Knudsen number. In the comparison results of the CV model, the maximum peak difference in the thermal wave reaches 75.08 K when the Knudsen number is 1.0. This demonstrates that the horizontal energy carried by the laser source significantly impacts the temperature distribution within the film.

6.
Int J Mol Sci ; 23(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36142569

RESUMO

In mammals, female fertility is determined by the outcome of follicular development (ovulation or atresia). The TGF-ß/SMAD signaling pathway is an important regulator of this outcome. However, the molecular mechanism by which the TGF-ß/SMAD signaling pathway regulates porcine follicular atresia has not been fully elucidated. Microrchidia family CW-type zinc finger 2 (MORC2) is anovel epigenetic regulatory protein widely expressed in plants, nematodes, and mammals. Our previous studies showed that MORC2 is a potential downstream target gene of the TGF-ß/SMAD signaling pathway. However, the role of MORC2 in porcine follicular atresia is unknown. To investigate this, qRT-PCR, western blotting, and TdT-mediated dUTP nick-end labeling were performed. Additionally, the luciferase activity assay was conductedto confirm that the TGF-ß/SMAD signaling pathway regulates MORC2. Our results demonstrate that MORC2 is animportant anti-apoptotic molecule that prevents porcine follicular atresia via a pathway involving mitochondrial apoptosis, not DNA repair. Notably, this studyrevealsthat the TGF-ß/SMAD signaling pathway inhibits porcine granulosa cell apoptosis by up-regulating MORC2. The transcription factor SMAD4 regulated the expression of MORC2 by binding to its promoter. Our results will help to reveal the mechanism underlying porcine follicular atresia and improve the reproductive efficiency of sows.


Assuntos
Atresia Folicular , Células da Granulosa , Animais , Feminino , Atresia Folicular/genética , Células da Granulosa/metabolismo , Luciferases/metabolismo , Mamíferos/metabolismo , Transdução de Sinais , Suínos , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
7.
Sci Total Environ ; 851(Pt 2): 158026, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-35973538

RESUMO

This study conducted an experimental analysis of how indoor air quality (IAQ) is influenced by the outdoor air pollutants levels, infiltration rate, and occupants' behaviours. The impacts of these factors on IAQ were analyzed using on-site measurements and numerical simulations. The results contribute to a better understanding of how to control the Indoor Particulate Level (IPL) for the specific conditions of the studied building. Results showed that occupant behaviour was the primary factor in determining the IPL, significantly changing the number of outdoor particles introduced to the building. Moreover, it was found that the IPL was exponentially correlated to the Outdoor Particulate Level (OPL). Based on numerical simulations, this study concluded that smaller particles do not always have more chance than larger particles of accessing the indoor environment through the building envelope. Meanwhile, a steady-state indoor particle concentration numerical model was established and verified using the 4-fold cross-validation method. Finally, simulation results identified that the room infiltration rate had a positive linear impact on IAQ if the OPL was under 30 µg/m3. This is because the increased air exchange rate can help to dilute indoor air pollutants when the outdoor air is relatively clean.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluição do Ar em Ambientes Fechados/análise , Material Particulado/análise , Tamanho da Partícula , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , Poeira/análise
8.
Animals (Basel) ; 12(12)2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35739867

RESUMO

Betaine is a well-established supplement used in livestock feeding. In our previous study, betaine was shown to result in the redistribution of body fat, a healthier steatosis phenotype, and an increased liver weight and triglyceride storage of the Landes goose liver, which is used for foie-gras production. However, these effects are not found in other species and strains, and the underlying mechanism is unclear. Here, we studied the underpinning molecular mechanisms by developing an in vitro fatty liver cell model using primary Landes goose hepatocytes and a high-glucose culture medium. Oil red-O staining, a mitochondrial membrane potential assay, and a qRT-PCR were used to quantify lipid droplet characteristics, mitochondrial ß-oxidation, and fatty acid metabolism-related gene expression, respectively. Our in vitro model successfully simulated steatosis caused by overfeeding. Betaine supplementation resulted in small, well-distributed lipid droplets, consistent with previous experiments in vivo. In addition, mitochondrial membrane potential was restored, and gene expression of fatty acid synthesis genes (e.g., sterol regulatory-element binding protein, diacylglycerol acyltransferase 1 and 2) was lower after betaine supplementation. By contrast, the expression of lipid hydrolysis transfer genes (mitochondrial transfer protein and lipoprotein lipase) was higher. Overall, the results provide a scientific basis and theoretical support for the use of betaine in animal production.

10.
Environ Sci Pollut Res Int ; 29(28): 43319-43340, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35091940

RESUMO

Traffic-related pollutants seriously affect human health, and the commute time to and from school is the time when students are exposed greatest to traffic pollution sources. Field measurements were conducted with hand-held instruments while walking along two selected commuting routes in winter and spring. The measured data were then compared with background monitoring data, and the respiratory deposition dose (RDD) was calculated to assess the exposure risk. Particulate matter intake from 2018 to 2020 was calculated. In winter, the average concentrations of PM2.5 and PM10 were higher in the afternoon than in the morning. The highest concentration was 2.94 times greater than the background value. The low-concentration distribution area of the low-traffic route that is off the main road (route B) was more significant than that of the high-traffic route that is near the main road (route A). Moreover, the RDD of route B was consistently lower than that of route A, while the average annual amount of PM2.5 inhalation on route B in 3 years was 16.3% lower than that on route A. Overall, route B is more suitable than route A for students to commute on foot. Based on the findings, a walking route located within a community is a good choice.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Exposição Ambiental/análise , Monitoramento Ambiental , Humanos , Material Particulado/análise , Instituições Acadêmicas , Meios de Transporte , Emissões de Veículos/análise
11.
Front Microbiol ; 13: 998647, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36620033

RESUMO

Introduction: Pichia pastoris is widely used for the production of recombinant proteins, but the low production efficiency hinders its wide application in biopharmaceuticals. Moreover, many biopharmaceutical-like proteins are accompanied by degradation during secretory expression in P. pastoris. Objective: In this study, we used human serum albumin and porcine follicle-stimulating hormone ß (HSA-pFSHß) fusion protein as a model protein to investigate whether YPS1 and YPT7 gene disruption and N-acetyl-L-cysteine (NAC) supplementation have synergistic effects to inhibit the degradation of recombinant proteins. Results and discussion: Our results showed that YPS1 gene disruption reduced the degradation of intact HSA-pFSHß and increased the yield of intact protein in the culture medium and cells without affecting the integrity of the cell wall. Moreover, the beneficial effects of YPS1 gene disruption were associated with the upregulation of the MAPK signaling pathway and maintenance of redox homeostasis. YPS1 gene disruption and NAC supplementation had synergistic effects on HSA-pFSHß production. In addition, disruption of vacuolar morphology by YPT7 gene disruption or NH4Cl treatment affected the production of recombinant HSA-pFSHß protein. Furthermore, YPT7 gene disruption inhibited the processing of signal peptide in high-level produced HSA-pFSHß strain. In conclusion, our results demonstrated that YPS1 disruption could reduce the degradation of intact HSA-pFSHß proteins, and synergistically increase the yield of intact HSA-pFSHß with NAC supplementation. This study provided a valuable reference for reducing recombinant protein degradation and therefore improving the yield of recombinant proteins in P. pastoris.

12.
Artigo em Inglês | MEDLINE | ID: mdl-36612933

RESUMO

While personal protective equipment (PPE) protects healthcare workers from viruses, it also increases the risk of heat stress. In this study, the effects of environmental heat stress, the insulation of the PPE inner-garment layer, and the personal cooling strategy on the physiological and perceptual responses of PPE-clad young college students were evaluated. Three levels of wet bulb globe temperatures (WBGT = 15 °C, 28 °C, and 32 °C) and two types of inner garments (0.37 clo and 0.75 clo) were chosen for this study. In an uncompensable heat stress environment (WBGT = 32 °C), the effects of two commercially available personal cooling systems, including a ventilation cooling system (VCS) and an ice pack cooling system (ICS) on the heat strain mitigation of PPE-clad participants were also assessed. At WBGT = 15 °C with 0.75 clo inner garments, mean skin temperatures were stabilized at 31.2 °C, Hskin was 60-65%, and HR was about 75.5 bpm, indicating that the working scenario was on the cooler side. At WBGT = 28 °C, Tskin plateaued at approximately 34.7 °C, and the participants reported "hot" thermal sensations. The insulation reduction in inner garments from 0.75 clo to 0.37 clo did not significantly improve the physiological thermal comfort of the participants. At WBGT = 32 °C, Tskin was maintained at 35.2-35.7 °C, Hskin was nearly 90% RH, Tcore exceeded 37.1 °C, and the mean HR was 91.9 bpm. These conditions indicated that such a working scenario was uncompensable, and personal cooling to mitigate heat stress was required. Relative to that in NCS (no cooling), the mean skin temperatures in ICS and VCS were reduced by 0.61 °C and 0.22 °C, respectively, and the heart rates were decreased by 10.7 and 8.5 bpm, respectively. Perceptual responses in ICS and VCS improved significantly throughout the entire field trials, with VCS outperforming ICS in the individual cooling effect.


Assuntos
Regulação da Temperatura Corporal , Transtornos de Estresse por Calor , Humanos , Roupa de Proteção , Temperatura Baixa , Temperatura , Temperatura Cutânea , Transtornos de Estresse por Calor/prevenção & controle , Temperatura Alta
13.
Appl Opt ; 60(30): 9269-9279, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34807074

RESUMO

The imaging of a large area scene is difficult to achieve for a single camera. Alternatively, a virtual large aperture can be synthesized by sub-aperture cooperation. We propose a solution through the combination of a coded aperture snapshot spectral imager and coprime array. This method reduces the amount of data by using a smaller sub-aperture for sampling. The position of the sub-aperture is determined according to the element distribution of the coprime array, so that the data obtained from each sampling are about the target object and its adjacent area, which can ensure high reconstruction accuracy. The feasibility of coprime sub-aperture sampling is verified by numerical simulation.

14.
Yeast ; 38(11): 601-611, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34486746

RESUMO

Our previous study revealed that N-acetyl-l-cysteine (NAC) could enhance the secretion of recombinant proteins by Pichia pastoris, but the corresponding molecular mechanisms are still unclear. In the present study, we explored whether other thiols have a similar action on the secretion of recombinant human serum albumin and porcine follicle-stimulating hormone fusion protein (HSA-pFSHß), to reveal the mechanism of NAC on HSA-pFSHß secretion. Transcriptome analysis showed that genes involved in oxidoreductase activity and oxidation-reduction process were upregulated in cells supplemented with NAC. The other three thiol-reducing regents including dimercaptopropanol (DT), thioglycolic acid, and mercaptolactic acid could improve HSA-pFSHß production in the culture supernatant. Among them, only DT had similar effect as NAC on HSA-pFSHß secretion and the increase of GSH content. Moreover, 1-20 mM GSH, 1-10 mM cysteine, or 1-20 mM N-acetyl-d-cysteine supplementation could improve the secretion of HSA-pFSHß. Furthermore, 0.4-3.2 mM ethacrynic acid, rather than 1-16 mM BSO could inhibit the effect of NAC on the production of HSA-pFSHß. These results indicated that NAC improved the secretion of HSA-pFSHß by increasing the intracellular GSH content through its thiol activity rather than as a precursor for GSH synthesis. In conclusion, our results demonstrate, for the first time, that the secretion of recombinant HSA-pFSHß in Pichia pastoris could be improved through thiol-reducing agent supplementation, and the mechanism of the effect NAC has on HSA-pFSHß secretion is associated with improving the intracellular GSH content.


Assuntos
Acetilcisteína , Albumina Sérica , Acetilcisteína/farmacologia , Animais , Hormônio Foliculoestimulante , Humanos , Pichia/genética , Saccharomycetales , Suínos
15.
Nat Commun ; 12(1): 3745, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34145285

RESUMO

Oxidative allylic C-H functionalization is a powerful tool to streamline organic synthesis as it minimizes the need for functional group activation and generates alkenyl-substituted products amenable to further chemical modifications. The intramolecular variants can be used to construct functionalized ring structures but remain limited in scope and by their frequent requirement for noble metal catalysts and stoichiometric chemical oxidants. Here we report an oxidant-free, electrocatalytic approach to achieve intramolecular oxidative allylic C-H amination and alkylation by employing tailored cobalt-salen complexes as catalysts. These reactions proceed through a radical mechanism and display broad tolerance of functional groups and alkene substitution patterns, allowing efficient coupling of di-, tri- and even tetrasubstituted alkenes with N- and C-nucleophiles to furnish high-value heterocyclic and carbocyclic structures.

16.
J Cell Sci ; 133(23)2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-33148612

RESUMO

SMARCA2, an evolutionarily conserved catalytic ATPase subunit of SWI/SNF complexes, has been implicated in development and diseases; however, its role in mammalian ovarian function and female fertility is unknown. Here, we identified and characterized the 3'-UTR of the porcine SMARCA2 gene and identified a novel adenylate number variation. Notably, this mutation was significantly associated with sow litter size traits and SMARCA2 levels, due to its influence on the stability of SMARCA2 mRNA in ovarian granulosa cells (GCs). Immunohistochemistry and functional analysis showed that SMARCA2 is involved in the regulation of follicular atresia by inhibiting GC apoptosis. In addition, miR-29c, a pro-apoptotic factor, was identified as a functional miRNA that targets SMARCA2 in GCs and mediates regulation of SMARCA2 expression via the NORFA-SMAD4 axis. Although a potential miR-29c-responsive element was identified within NORFA, negative regulation of miR-29c expression by NORFA was not due to activity as a competing endogenous RNA. In conclusion, our findings demonstrate that SMARCA2 is a candidate gene for sow litter size traits, because it regulates follicular atresia and GC apoptosis. Additionally, we have defined a novel candidate pathway for sow fertility, the NORFA-TGFBR2-SMAD4-miR-29c-SMARCA2 pathway.This article has an associated First Person interview with the first author of the paper.


Assuntos
Apoptose , Fertilidade , Atresia Folicular , Células da Granulosa/citologia , MicroRNAs , Fatores de Transcrição/genética , Animais , Apoptose/genética , Feminino , Fertilidade/genética , MicroRNAs/genética , Suínos
17.
Sensors (Basel) ; 20(16)2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32806605

RESUMO

In computational ghost imaging, a spatial light modulator (SLM) can be used to modulate the light field. The relative locations and the number of light point pixels on an SLM affect the imaging quality. Usually, SLMs are two-dimensional arrays which are drawn uniformly or are randomly sparse. However, the patterns formed by a uniform array are periodic when the number of light point pixels is small, and the images formed by a random sparse array suffer from large background noise. In this paper, we introduce a coprime array based on the Eisenstein integer to optimize the light point pixel arrangement. A coprime array is widely used as a microwave radar receiving array, but less implemented in optics. This is the first time that a coprime array based on Eisenstein integer has been introduced in computational ghost imaging. A coprime array with this structure enhances the imaging quality when limited measurements are recorded, and it reduces background noise and avoids periodicity. All results are verified by numerical simulation.

18.
PLoS One ; 15(6): e0233340, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32492038

RESUMO

The miniaturization of stone tools, as reflected through the systematic production of bladelets and bladelet tools (microliths), characterized many industries of the Late Pleistocene, with the Levantine Epipalaeolithic serving as a well-studied example. It is commonly held that microliths were used as modular inserts in composite projectiles, while their incorporation in other tools for different tasks is generally overlooked, the latter aspect being the main focus of this paper. We present here a more inclusive approach through a case study of the Geometric Kebaran (Middle Epipalaeolithic, ca. 18,500-15,000 cal BP) site of Neve David, Mount Carmel, Israel. Recent excavations at the site exposed a variety of features, and one well-preserved shallow pit provided a large lithic assemblage with ca. 90 microliths. We studied this assemblage using both the low- and high- magnification use-wear protocols, accompanied by a range of experiments. Our results show that a) the fragmentation rate is very high in this assemblage (ca. 90%), b) most of the microliths have identifiable use-wear, c) the microliths were commonly used as inserts in composite projectiles, d) many microliths were used for functions not related to weaponry and hunting, such as wood-working, weed harvesting and meat processing. These findings strongly support the suggestion that the small insets, regardless of their specific type (trapeze, rectangle, backed/retouched bladelet), were used in a wide variety of composite tools. We argue that such a versatile approach and flexibility in the use of microliths reflect a technological advantage where a minimal set of microlithic types, produced in large numbers, could provide the required elements for weapons, as well as for a variety of cutting, processing and harvesting tools needed for mundane tasks at a large Middle Epipalaeolithic camp.


Assuntos
Armas/história , Arqueologia , Desenho de Equipamento/história , Fenômenos Geológicos , História Antiga , Humanos , Indústrias/história , Israel , Miniaturização , Tecnologia/história
19.
J Genet Genomics ; 47(12): 735-742, 2020 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-33612456

RESUMO

Tuberous sclerosis complex (TSC) is a dominant genetic neurocutaneous syndrome characterized by multiple organ hamartomas. Although rodent models bearing a germline mutation in either TSC1 or TSC2 gene have been generated, they do not develop pathogenic lesions matching those seen in patients with TSC because of the significant differences between mice and humans, highlighting the need for an improved large animal model of TSC. Here, we successfully generate monoallelic TSC1-modified Bama miniature pigs using the CRISPR/Cas9 system along with somatic cell nuclear transfer (SCNT) technology. The expression of phosphorylated target ribosomal protein S6 is significantly enhanced in the piglets, indicating that disruption of a TSC1 allele activate the mechanistic target of rapamycin (mTOR) signaling pathway. Notably, differing from the mouse TSC models reported previously, the TSC1+/- Bama miniature pig developed cardiac rhabdomyoma and subependymal nodules, resembling the major clinical features that occur in patients with TSC. These TSC1+/- Bama miniature pigs could serve as valuable large animal models for further elucidation of the pathogenesis of TSC and the development of therapeutic strategies for TSC disease.


Assuntos
Neoplasias Cardíacas/genética , Rabdomioma/genética , Proteína S6 Ribossômica/genética , Proteína 1 do Complexo Esclerose Tuberosa/genética , Esclerose Tuberosa/genética , Alelos , Animais , Sistemas CRISPR-Cas/genética , Modelos Animais de Doenças , Neoplasias Cardíacas/complicações , Neoplasias Cardíacas/patologia , Humanos , Camundongos , Mutação/genética , Técnicas de Transferência Nuclear , Rabdomioma/complicações , Rabdomioma/patologia , Suínos/genética , Porco Miniatura/genética , Serina-Treonina Quinases TOR/genética , Esclerose Tuberosa/complicações , Esclerose Tuberosa/patologia , Proteína 2 do Complexo Esclerose Tuberosa/genética
20.
Analyst ; 144(19): 5829-5841, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31475698

RESUMO

A novel dual-shell magnetic nanoparticle coated with a cationic covalent organic framework, containing ethidium bromide, is easily prepared, characterized and applied as an adsorbent for fast, simple and highly selective capture of nine hydroxylated polycyclic aromatic hydrocarbons in urine samples of non-smokers and smokers who smoked cigarettes with different tar yields. This is the first time that a cationic crystalline framework with high thermal and chemical stability was used for magnetic solid phase extraction. Multiple probes and quantum chemistry theory calculations were conducted to describe the versatile adsorption property directly and quantifiably. A method using high-performance liquid chromatography with a fluorescence detector based on the prepared magnetic adsorbent was established and used to investigate differences in the exposure levels of OH-PAHs in non-smokers and smokers smoking cigarettes with different tar yields. All the OH-PAH analyses present good linearities in the range of 0.1-100 ng mL-1, with R2 > 0.9965. The LOD for the 9 OH-PAHs ranged from 0.0030 to 0.0096 ng mL-1 and the LOQ ranged from 0.096 to 0.030 ng mL-1. The recoveries of the 9 OH-PAHs ranged from 93.3 to 121.3% with the RSD ranging from 0.47 to 3.53%. These results imply that the versatile EB-DS MNPs as adsorbents have great potential in the analysis of trace targets in samples with complex matrices.


Assuntos
Nanopartículas de Magnetita/química , Estruturas Metalorgânicas/química , Hidrocarbonetos Policíclicos Aromáticos/urina , Fumantes , Adsorção , Cromatografia Líquida de Alta Pressão/métodos , Etídio/química , Humanos , Limite de Detecção , Hidrocarbonetos Policíclicos Aromáticos/química , Dióxido de Silício/química , Extração em Fase Sólida/métodos
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