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1.
Braz J Otorhinolaryngol ; 90(6): 101467, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39079457

RESUMO

OBJECTIVES: One of the most common sensory impairments in the elderly is age-related hearing loss, and individuals with this condition have a higher risk of mild cognitive impairment than the overall aged population. The purpose of this study was to conduct a systematic review of the literature in order to evaluate the evidence supporting the hypothesis that mild cognitive impairment may be developed in patients with age-related hearing loss. METHODS: The PRISMA principles were followed when searching the databases of the China Knowledge Network, Wanfang, China Biomedical Literature Database, Pub Med, Cochrane Library, Embase, and Web of Science. Two investigators independently carried out the quality assessment, data extraction, and literature review of the eligible studies. Stata 17.0 was used to finish the statistical analysis and descriptive results. RESULTS: A total of 13 articles containing 2,222,036 individuals who were evaluated for demographic traits, factors associated with age-related hearing loss, vascular neurologic factors, and psychological factors were included after 2166 search records were found in the database. In patients with age-related hearing loss, eleven factors were found to be risk factors for the development of mild cognitive impairment: age (OR = 1.63; 95% CI 1.09-2.43), male (OR = 1.29; 95% CI 1.14-1.47), degree of hearing loss (OR = 1.35; 95% CI 1.03-1.75), not wearing hearing aids (OR = 1.56; 95% CI 1.37-1.79), cerebrovascular disease (OR = 1.41; 95% CI 1.17-1.69), cardiovascular disease (OR = 1.29; 95% CI 1.07-1.55), diabetes mellitus (OR = 1.28; 95% CI 1.20-1.35), head injury (OR = 1.22; 95% CI 1.13-1.33), alcohol consumption (OR = 1.28; 95% CI 1.14-1.43), and tobacco use (OR = 1.19; 95% CI 1.14-1.25), and depression (OR = 1.63; 95% CI 1.47-1.81). CONCLUSION: Caregivers can customize care strategies to decrease the occurrence of mild cognitive impairment in elderly deaf patients by considering demographic traits, factors associated with age-related hearing loss, vascular-neurologic factors, and psychological factors.

2.
J Hazard Mater ; 476: 135014, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38941839

RESUMO

Pt(II) polypyridine complex-based probe exhibits promising performance in anion detection by the change of the absorption and emission properties based on supramolecular self-assembly. However, whether one can develop a modulation strategy of the counter anion to boost the detection sensitivity and anti-interference capability of the Pt(II) complex-based probe remains a big challenge. Here, an effective modulation strategy was proposed by precisely regulating the interaction energy through adjusting the type of the counter anions, and a series of probes have been synthesized by counter anion (X = Cl-, ClO4-, PF6-) exchange in [Pt(tpy)Cl]·X (tpy=2,2':6',2''-terpyridine), and thus the colorimetric-luminescence dual-mode detection toward nitrate was achieved. The optimal [Pt(tpy)Cl]·Cl probe shows superior nitrate detection performance including a limit of detection (LOD) (8.68 nM), rapid response (<0.5 s), an excellent selectivity and anti-interference capability even facing 14 common anions. Moreover, a polyvinyl alcohol (PVA) sponge-based sensing chip loaded with the probe enables the ultra-sensitive detection of nitrate particles with an ultralow detection limit of 7.6 pg, and it was further integrated into a detection pen for the accurate recognition of nitrate particles in real scenarios. The proposed counter-anion modulation strategy is expected to start a new frontier for the exploration of novel Pt(II) complex-based probes.

3.
Semin Cancer Biol ; 95: 13-24, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37355214

RESUMO

Therapeutic antibodies are the largest class of biotherapeutics and have been successful in treating human diseases. However, the design and discovery of antibody drugs remains challenging and time-consuming. Recently, artificial intelligence technology has had an incredible impact on antibody design and discovery, resulting in significant advances in antibody discovery, optimization, and developability. This review summarizes major machine learning (ML) methods and their applications for computational predictors of antibody structure and antigen interface/interaction, as well as the evaluation of antibody developability. Additionally, this review addresses the current status of ML-based therapeutic antibodies under preclinical and clinical phases. While many challenges remain, ML may offer a new therapeutic option for the future direction of fully computational antibody design.


Assuntos
Inteligência Artificial , Aprendizado de Máquina , Humanos
4.
Environ Sci Pollut Res Int ; 30(20): 58282-58294, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36977874

RESUMO

Phytoremediation is considered an effective method for indoor air pollution control. The removal rate and mechanism of benzene in air by two plants, Tradescantia zebrina Bosse and Epipremnum aureum (Linden ex André) G. S. Bunting, were investigated through fumigation experiments under the condition of plant hydroponics culturing. Results showed that the plant removal rates increased with increase in benzene concentration in air. When the benzene concentration in air was set at 432.25-1314.75 mg·m-3, the removal rates of T. zebrina and E. aureum ranged from 23.05 ± 3.07 to 57.42 ± 8.28 mg·kg-1·h-1 FW and from 18.82 ± 3.73 to 101.58 ± 21.20 mg·kg-1·h-1 FW, respectively. The removal capacity was positively related to the transpiration rate of plants, indicating that gas exchange rate could be a key factor for the evaluation of removal capacity. There existed fast reversible transport of benzene on air-shoot interface and root-solution interface. After shoot exposure to benzene for 1 h, downward transport was the dominant mechanism in the removal of benzene in air by T. zebrina, while in vivo fixation was the dominant mechanism at exposure time of 3 and 8 h. Within 1-8 h of shoot exposure time, in vivo fixation capacity was always the key factor affecting the removal rate of benzene in the air by E. aureum. Contribution ratio of in vivo fixation in the total benzene removal rate increased from 6.29 to 92.29% for T. zebrina and from 73.22 to 98.42% for E. aureum in the experimental conditions. Reactive oxygen species (ROS) burst induced by benzene exposure was responsible for the contribution ratio change of different mechanisms in the total removal rate, which also was verified by the change of activities of antioxidant enzymes (CAT, POD, and SOD). Transpiration rate and antioxidant enzyme activity could be considered parameters to evaluate the plant removal ability to benzene and to screen plants for establishment of plant-microbe combination technology.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Araceae , Tradescantia , Benzeno , Antioxidantes , Tilia , Plantas
5.
J Hazard Mater ; 438: 129565, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35999750

RESUMO

Membrane separation based on smart materials with responsive wettability has attracted great attention due to the excellent performance of controllable oil-water separation. Herein, responsive copolymer originated from N-isopropylacrylamide and 2-(dimethylamino) ethyl methacrylate was synthesized and electrospun with polyacrylonitrile to fabricate smart composite membrane. The introduction of the responsive copolymer endowed the membrane with stimuli-responsive wettability to pH and temperature. Specifically, at the initial state, water was selectively blocked while oil passed through the membrane. After treatment with acidic water or CO2, the reverse separation was realized due to the protonation of the tertiary amine group in the copolymer. Water was selectively passed through the membrane after heat treatment because of the structural change of membrane upon temperature. The developed membrane was able to separate different types of oil-water mixtures and surfactant-stabled emulsions with high efficiency. Additionally, two membranes controlled by temperature and pH were designed to construct a logic AND gate for oil-water separation, and the results demonstrated that only the temperature and acidity of the solution were simultaneously satisfied, the water could flow through the valve combination, and such capability made this smart membrane great potential for remotely controlling the oil-water separation process.


Assuntos
Resinas Acrílicas , Óleos , Óleos/química , Polímeros/química , Água/química , Molhabilidade
6.
J Anim Physiol Anim Nutr (Berl) ; 106(6): 1268-1276, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34862676

RESUMO

A total of 60 sows (Landrace × Yorkshire, average parity was 1.39) were used to evaluate the effects of soy isoflavones (ISO) supplementation on reproductive performance, serum antioxidant enzyme parameters, and milk compositions of sows, and the growth performance of offspring. Sows were randomly assigned to 4 groups based on the parity. There were 15 replicates per treatment. Dietary treatments were based on a corn-soybean meal-based basal diet and supplemented with 0, 10, 20, or 40 mg/kg ISO. With the increase of the ISO dosage, average daily feed intake of sows increased linearly; oestrus interval decreased linearly and quadratically. In addition, on day 10 of lactation, linear increases in serum superoxide dismutase levels, linear and quadratic increases in serum total antioxidant capacity, and linear decreases in serum malondialdehyde levels were observed in increasing ISO dosage in the diet of sows. The body weight on day 10 and 21 and the average daily gain during days 3-10 and 3-21 of offspring increased linearly at graduated doses of ISO increased. Therefore, feeding sows with graded levels of ISO containing diet during late-gestation and lactation periods improved the reproductive performance of sows and the growth performance of their offspring in a dose-dependent manner.


Assuntos
Antioxidantes , Isoflavonas , Suínos , Gravidez , Animais , Feminino , Antioxidantes/farmacologia , Ração Animal/análise , Desmame , Lactação , Dieta/veterinária , Suplementos Nutricionais , Isoflavonas/farmacologia
7.
Basic Clin Pharmacol Toxicol ; 128(2): 241-255, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32955161

RESUMO

Baicalin has been reported to protect mice against Salmonella typhimurium (S. typhimurium) infection, while its molecular mechanisms are unclear. In this study, multiplicity of infection (MOI) and observation time were measured. Cell viability and LDH levels were examined in RAW264.7 cells and H9 cells. RAW264.7 cells were stimulated with S typhimurium in the presence or absence of Baicalin, and the levels of pro-inflammatory cytokines were detected by enzyme-linked immunosorbent assay (ELISA). The changes in reactive oxygen species (ROS) production were determined by fluorescence microscopy and ELISA. The autophagy and TLR4/MAPK/NF-κB signalling pathway were examined by immunofluorescence microscopy, quantitative reverse transcription-polymerase chain reaction and Western blotting. The results indicated that MOI of 30 and duration of autophagy evident at 5 h were applicable to this study. Baicalin prevented death of macrophages, promoted bactericidal activity, decreased the levels of pro-inflammatory cytokines and ROS and reduced the changes of key biomarkers in autophagy and TLR4/MAPK/NF-κB signalling pathway infected by S typhimurium. TLR4-overexpressed cells, autophagy and TLR4/MAPK/NF-κB signalling pathway were activated by S typhimurium, which was suppressed by Baicalin. Our findings indicated that Baicalin exerts anti-inflammatory and cell-protective effects, and it mediates autophagy by down-regulating the activity of TLR4 infected by S typhimurium.


Assuntos
Anti-Inflamatórios/farmacologia , Autofagia/efeitos dos fármacos , Flavonoides/farmacologia , Células-Tronco Embrionárias Humanas/efeitos dos fármacos , Inflamação/prevenção & controle , Macrófagos/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Infecções por Salmonella/prevenção & controle , Salmonella typhimurium/patogenicidade , Receptor 4 Toll-Like/metabolismo , Animais , Citocinas/metabolismo , Células-Tronco Embrionárias Humanas/enzimologia , Células-Tronco Embrionárias Humanas/microbiologia , Células-Tronco Embrionárias Humanas/patologia , Humanos , Inflamação/enzimologia , Inflamação/microbiologia , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Macrófagos/enzimologia , Macrófagos/microbiologia , Macrófagos/patologia , Camundongos , NF-kappa B/genética , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Infecções por Salmonella/enzimologia , Infecções por Salmonella/microbiologia , Infecções por Salmonella/patologia , Transdução de Sinais , Receptor 4 Toll-Like/genética
8.
Environ Sci Pollut Res Int ; 28(7): 8782-8790, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33067793

RESUMO

The formaldehyde dehydrogenase (FADH) activity in plants is essential to the removal of airborne formaldehyde (FA) by plants. A rapid and efficient method was established to assess the FADH activity in plants by analyzing the efficiencies of the extracts of fresh and enzyme-inactivated leaves to degrade FA, with the enzyme-inactivated leaves prepared by freezing with liquid nitrogen. The efficiencies of airborne FA dissipated by different plants were evaluated through the FA fumigation experiments using four selected plants, with the results analyzed against the calculated leaf FADH activities. Fresh and enzyme-inactivated leaf extracts degraded FA to different extents. The degradative efficiencies of leaf extracts were positively related to the initial FA test levels at 6-18 mg l-1. The relative plant-leaf FADH activities formed the order of Chenopodium album L. > Atenia cordifolia > Plantain > Aloe, which was in line with the observed FA dissipating efficiencies of the plants exposed to 0.72 mg m-3 airborne FA for 24 h. Other dominant degrading mechanisms in plant leaves resulted in higher dissipating efficiencies of Plantain over that of Atenia cordifolia when exposed to 1.56 mg m-3 FA for 24 h. The established method could be applied to estimate the FADH activity in plants for assessment of the plant remediation efficiency of FA in air at lower concentrations.


Assuntos
Aldeído Oxirredutases , Formaldeído , Oxirredução , Plantas
9.
Neurosci Lett ; 728: 134947, 2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32276104

RESUMO

Shh/Gli1 signaling plays important roles in development of spinal cord. How it is involved in spinal cord injury (SCI) remains unclear. In this study, we explored the roles of Shh/Gli1 signaling in SCI by using Shh signaling reporter Gli1lz mice and Gli1 mutant Gli1lz/lz mice. For detecting the Shh/Gli1 signaling after SCI, X-gal staining and double-immunostaining of Shh/PDGFR-ß, Shh/GFAP and LacZ/GFAP was conducted at 3 days post injury (dpi) on Gli1lz mice. To investigate the effects of Gli1 mutation on pathological changes after SCI, astrocytic proliferation and the content of intra-parenchymal Evans Blue were evaluated at 7dpi in wild-type and Gli1lz/lz mice. Furthermore, locomotor recovery was assessed by BMS scoring at 1, 3, 5 and 7dpi. The results of X-gal staining and immunohistochemistry showed that Shh/Gli1 signaling was mainly activated in reactive astrocytes after SCI. The 5-bromo-2-deoxyuridine (BrdU) incorporation assay showed that mutation of Gli1 did not affect the proliferation of astrocytes. However, the leakage of Evans Blue was significantly increased in the injured cord of Gli1lz/lz mice compared to wild-type mice. In addition, locomotor recovery was significantly impaired in the Gli1lz/lz mice. The findings demonstrated that Shh/Gli1 signaling could be induced in reactive astrocytes by SCI, and plays important role in permeability of blood-spinal cord barrier (BSCB) and locomotor recovery after SCI.


Assuntos
Proteínas Hedgehog/metabolismo , Traumatismos da Medula Espinal/metabolismo , Proteína GLI1 em Dedos de Zinco/metabolismo , Animais , Astrócitos/metabolismo , Modelos Animais de Doenças , Locomoção/fisiologia , Camundongos Endogâmicos C57BL , Recuperação de Função Fisiológica/efeitos dos fármacos , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/fisiopatologia
10.
Int J Phytoremediation ; 21(13): 1296-1304, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31617392

RESUMO

Uptake and in-plant transport of formaldehyde by six plants with or without soil microorganisms were investigated. The capabilities of fresh and boiled leaf extracts to dissipate added formaldehyde were also measured to evaluate formaldehyde metabolism in plant tissues. Results show that when the initial formaldehyde level in air was 0.56 ± 0.04 mg·m-3, the removal rate in the plant-only systems varied from 1.91 to 31.8 µg·h-1·g-1 FW (fresh weight). The removal rate of plants in the plant-only systems were ordered as Helianthus annuus Linn > Lycopersicon esculentum Miller > Oryza sativa > Sansevieria trifasciata Prain > Bryophyllum pinnatum > Mesembryanthemum cordifolium L. f. Most reduction of formaldehyde in the air was due to degradation by active components in the plant tissues, of which 4-64% of these were through to be enzymatic reactions. In the microbe-plant systems, formaldehyde removal rates increased by 0.24-9.53 fold compared to the plant-only systems, with approximately 19.6-90.5% of the formaldehyde reduction resulting from microbial degradation. Microorganisms added to the rhizosphere solution enhanced phytoremediation by increasing the downward transport of formaldehyde and its release by roots. Results suggest a new means to screen for efficient plant species that can be used for phytoremediation of indoor air.


Assuntos
Rizosfera , Poluentes do Solo , Biodegradação Ambiental , Formaldeído , Raízes de Plantas , Solo
11.
Mol Cell Endocrinol ; 498: 110536, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31401349

RESUMO

Clinical studies have revealed that the risk of Alzheimer's disease (AD) in men is increased by age-related androgen depletion. The level of ß-amyloid (Aß) is elevated in the brains of AD patients, and Aß is believed to play a critical role in the pathology of AD. Some studies have indicated that androgens affect AD risk by regulating the metabolism of Aß by an unclear mechanism. In this study, we investigated the role of the extracellular matrix metalloproteinase inducer (CD147) in this action. Initially, we demonstrated that androgens positively regulate the expression of CD147 in adult male rats and SH-SY5Y cells. Furthermore, this regulation may involve androgen receptor (AR). Additionally, interference of CD147 expression decreased the clearance of Aß in culture medium and reduced cell viability. It also affected the morphology of the cells and the expression of apoptosis-related proteins. Finally, we found that interference of CD147 expression blocked the dihydrotestosterone (DHT)-induced reduction in Aß and the protection of cells. DHT regulates MMP-2's expression through CD147. Together, these results imply that androgen regulation of Aß and cell protection may be affected by interfering with the expression of CD147.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Basigina/metabolismo , Di-Hidrotestosterona/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Metaloproteinases da Matriz/metabolismo , Neuroblastoma/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Androgênios/farmacologia , Animais , Apoptose/efeitos dos fármacos , Basigina/genética , Ativação Enzimática , Humanos , Masculino , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Ratos , Ratos Sprague-Dawley , Células Tumorais Cultivadas
12.
J Environ Health Sci Eng ; 17(1): 141-150, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31321042

RESUMO

Indoor potted plants played an important role in the removal of air-borne VOCs. According to the difference between plant fresh extracts and boiled extracts on breakdown ability to the added formaldehyde, a simple quantitative evaluation method was used to identify the mechanisms of formaldehyde removal from the air by wild Taraxacum mongolicum Hand.-Mazz. and Plantago asiatica L.. After shoots exposure to formaldehyde (1.28 mg/m3 in the air) for 24 h, the formaldehyde removal rates of P. asiatica and T. mongolicum were 73.18 and 121.20 mg/h/kg FW (fresh weight), respectively. Formaldehyde can be transported from the air to the rhizosphere solution by plants, and the maximum rates of transmission by T. mongolicum and P. asiatica were 23.73 and 83.08 mg/h/kg FW, respectively. Although plant metabolism was responsible for formaldehyde loss in the air-plant-solution system, and the metabolic activity depended on the enzymatic and redox reactions in the plants, P. asiatica and T. mongolicum are still good candidate species for developing phyto-microbial technologies. The redox reaction was the main mechanism used by P. asiatica shoots to dissipate formaldehyde, while the enzymatic reaction was the main mechanism used by T. mongolicum. The higher oxidative potential and lower defensive enzyme activity in P. asiatica shoots led to its higher formaldehyde removal rate compared to T. mongolicum. Meanwhile, the stronger redox reaction ability in the T. mongolicum roots was partly responsible for its lower formaldehyde transmission rate. The results show two plants have strong tolerance to formaldehyde in the air and good formaldehyde removal ability.

13.
Artigo em Inglês | MEDLINE | ID: mdl-30596331

RESUMO

The roles of enzymatic reactions and redox reactions caused by reactive oxygen species (ROS) in formaldehyde metabolism in tomatoes and wheat seedlings and the changes in peroxidase (POD) and catalase (CAT) activities in plants were investigated. Differences in the breakdown of added formaldehyde between fresh and boiled plant extracts were determined to calculate the contributions of different removal mechanisms. Two plant seedlings efficiently removed formaldehyde from air when its level varied from 0.65 to 1.91 mg m-3; meanwhile, the maximum rate at which tomato seedlings transported formaldehyde from air to the rhizosphere solution reached 182.26 µg h-1 kg-1 FW (fresh weight). Metabolism in plants was mainly responsible for the formaldehyde dissipation. The enzymatic contribution to formaldehyde dissipation decreased with increasing shoot exposure time or air formaldehyde level, while the redox contribution increased in importance because of an increasing level of ROS. The different enzymatic antioxidant activities of plants resulted in different levels of ROS and hence different tolerance and removal efficiencies toward formaldehyde. The self-enhancing ability of plants to remove formaldehyde via redox reactions suggested that the formaldehyde removal efficiency could be enhanced by plant adaptation to environmental stress.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/prevenção & controle , Antioxidantes/metabolismo , Formaldeído/análise , Espécies Reativas de Oxigênio/metabolismo , Plântula/enzimologia , Catalase/metabolismo , Solanum lycopersicum/enzimologia , Solanum lycopersicum/crescimento & desenvolvimento , Oxirredução , Peroxidases/metabolismo , Plântula/crescimento & desenvolvimento , Estresse Fisiológico , Triticum/enzimologia , Triticum/crescimento & desenvolvimento
14.
Bioresour Technol ; 278: 464-467, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30691955

RESUMO

The effect of sodium formate (SF), calcium formate (CF) and nickel formate (NF) as additives on analytical pyrolysis performance of kraft lignin was conducted. The results showed that these formates promoted the releasing of volatiles, leading to the rapid degradation of kraft lignin. High relative content of monophenols (53.77%), especially of guaiacol (23.65%), were achieved from the pyrolysis of pure lignin. The relative content of guaiacol was dramatically decreased after the adding of formates in kraft lignin. The relative content of polyphenols such as 3-methylcatechol and 4-methylcatechol reached to 16.97%, 16.23% and 21.95% with the formates of SF, CF and NF, respectively. The NF showed the highest selectivity of polyphenols and hydrocarbons. The increase of polyphenols and hydrocarbons from NF was the synergetic effect of the hydrogen radical reaction from the formic functional groups under the catalysis of Ni and/or NiO produced from the NF pyrolysis process.


Assuntos
Catecóis/química , Formiatos/química , Lignina/química , Catálise , Pirólise
15.
Sensors (Basel) ; 18(5)2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29762494

RESUMO

A simple and easy method was implemented for the contemporary detection of cadmium (Cd2+) and lead (Pb2+) ions using 1,3,6,8-pyrenetetrasulfonic acid sodium salt-functionalized carbon nanotubes nanocomposites (PyTS⁻CNTs). The morphology and composition of the obtained PyTS⁻CNTs were characterized using scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and X-ray photoelectron spectroscopy (XPS). The experimental results confirmed that the fabricated PyTS⁻CNTs exhibited good selectivity and sensitivity for metal ion-sensing owing to the insertion of sulfonic acid groups. For Cd2+ and Pb2+, some of the electrochemical sensing parameters were evaluated by varying data such as the PyTS⁻CNT quantity loaded on the pyrolytic graphite electrode (PGE), pH of the acetate buffer, deposition time, and deposition potential. These parameters were optimized with differential pulse anodic sweeping voltammetry (DPASV). Under the optimal condition, the stripping peak current of the PyTS⁻CNTs/Nafion/PGE varies linearly with the heavy metal ion concentration, ranging from 1.0 µg L-1 to 90 µg L-1 for Cd2+ and from 1.0 µg L-1 to 110 µg L-1 for Pb2+. The limits of detection were estimated to be approximately 0.8 µg L-1 for Cd2+ and 0.02 µg L-1 for Pb2+. The proposed PyTS⁻CNTs/Nafion/PGE can be used as a rapid, simple, and controllable electrochemical sensor for the determination of toxic Cd2+ and Pb2+.

16.
Anim Reprod Sci ; 161: 40-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26297622

RESUMO

Nerve growth factor (NGF), which is required for the survival and differentiation of the nervous system, is also thought to play an important role in the development of mammalian reproductive tissues. To explore the function of NGF in the male reproductive system of non-mammalian animals, we determined the presence of NGF and its receptor, tyrosine kinase receptor A (TrkA), in rooster testes and investigated the regulation of NGF and TrkA expression by follicle-stimulating hormone (FSH). The mRNA and protein levels of NGF and TrkA in 6-week-old rooster testes were lower than those in 12-, 16- or 20-week age groups; levels were highest in the 16-week group. Immunohistochemistry showed that NGF and TrkA were both detected in spermatogonia, spermatocytes and spermatids. NGF immunoreactivity was observed in Leydig cells and strong TrkA signals were present in Sertoli cells. Meanwhile, FSH increased TrkA transcript levels in rooster testes in a dose-dependent manner. We present novel evidence for the developmental and FSH-regulated expression of the NGF/TrkA system, and our findings suggest that the NGF/TrkA system may play a prominent role in chicken spermatogenesis.


Assuntos
Fator de Crescimento Neural/biossíntese , Receptor trkA/biossíntese , Testículo/metabolismo , Animais , Western Blotting/veterinária , Galinhas , Hormônio Foliculoestimulante/farmacologia , Expressão Gênica/efeitos dos fármacos , Masculino , RNA/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Testículo/efeitos dos fármacos
17.
PLoS One ; 10(4): e0122851, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25856555

RESUMO

MiRNAs are small noncoding RNAs that play important roles in various biological processes including tumorigenesis. However, little is known about the expression and function of miR-506 in nasopharyngeal carcinoma (NPC). In this study, we showed that miR-506 was downregulated in nasopharyngeal carcinoma (NPC) cell lines and tissues. Ectopic expression of miR-506 dramatically suppressed cell proliferation, colony formation and invasion. Moreover, we identified the Forkhead box Q1 (FOXQ1) gene as a novel direct target of miR-506. MiR-506 exerts its tumor suppressor function through inhibition of the FOXQ1, which was involved in tumor metastasis and proliferation in various cancers. Furthermore, the expression of FOXQ1 is up-regulated in NPC cell lines and tissues. Taken together, our results indicate that miR-506 functions as a tumor suppressor miRNA in NPC and that its suppressive effects are mediated chiefly by repressing FOXQ1 expression.


Assuntos
Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias Nasofaríngeas/genética , Sequência de Bases , Carcinoma , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Cultura em Câmaras de Difusão , Fatores de Transcrição Forkhead/metabolismo , Genes Reporter , Humanos , Luciferases/genética , Luciferases/metabolismo , MicroRNAs/metabolismo , Dados de Sequência Molecular , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Transdução de Sinais
18.
J Hazard Mater ; 291: 120-8, 2015 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-25771217

RESUMO

The foliar uptake and transport of formaldehyde into Bracket plants from air via leaves and roots to external water was investigated in an air-plant-water system. The results indicated that formaldehyde could be quickly taken up by plant tissues, and that formaldehyde accumulated in leaves could be released rapidly back into air when the formaldehyde level in air was diminished. This rapid reversible translocation of formaldehyde between plant leaves and air resulted in high formaldehyde concentrations in leaf dews, depending upon exposure levels of formaldehyde in air. Meanwhile, formaldehyde could be transported from air to plant rhizosphere solution through downward transport. The concentration of formaldehyde in rhizosphere solutions increased with exposure time and the formaldehyde level in air. The efficiency of the leaf extracts to break down formaldehyde increased, probably because of an increase in oxidative potential of the leaf extracts. Taken together, the main mechanism of formaldehyde loss in air can be attributed to the accumulation by (or breakdown in) plant tissues; the removal rate of formaldehyde from air reached 135 µg h(-1) plant(-1) in the experimental condition.


Assuntos
Poluentes Atmosféricos/isolamento & purificação , Formaldeído/isolamento & purificação , Formaldeído/metabolismo , Liliaceae/metabolismo , Folhas de Planta/metabolismo , Transporte Biológico , Oxirredução , Extratos Vegetais/química , Rizosfera , Plântula/metabolismo , Volatilização
19.
Biol Trace Elem Res ; 153(1-3): 403-10, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23575899

RESUMO

To better understand the mechanism of cadmium (Cd)-induced apoptosis of porcine granulosa cells, we examined the nuclear factor-kappa B (NF-κB) p65 subunits intracellular translocation and the expression of some downstream apoptotic-related genes. Apoptosis and reactive oxygen species (ROS) production in porcine granulosa cells exposed to cadmium chloride (CdCl2) were determined by acridine orange/ethidium bromide double staining and 2,7-dichlorodihydro-fluorescein-diacetate oxidation staining, respectively. The results showed that the apoptosis of porcine granulosa cells induced by CdCl2 significantly increased in a time- and dose-dependent manner along with the increasing of ROS production, and 10 µM parthenolide, an inhibitor NF-κB, can accelerate the process of apoptosis. Moreover, immunofluorescence and western blot results showed that CdCl2 could stimulate the translocation of p65 into nucleus in porcine granulosa cells. Furthermore, CdCl2 also significantly stimulate the expression of Bcl-2 proteins in porcine granulosa cells than that in the control. In contrast, we did not find any change of Bax expression in granulosa cells upon exposure of cadmium. Taken together, these results demonstrate that the activation of NF-κB pathway may play a crucial role in cadmium-induced apoptosis of porcine granulosa cells.


Assuntos
Apoptose/efeitos dos fármacos , Cádmio/toxicidade , Células da Granulosa/efeitos dos fármacos , NF-kappa B/metabolismo , Animais , Feminino , Células da Granulosa/citologia , Células da Granulosa/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos/farmacologia , Suínos
20.
Environ Pollut ; 169: 160-6, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22209516

RESUMO

The concentration and composition of PAHs emitted from biomass cooking fuel were characterized in a rural non-smoking household in northern China. Twenty-two parent PAHs (pPAHs), 12 nitro-PAHs (nPAHs), and 4 oxy-PAHs (oPAHs) were measured in the kitchen, bedroom, and outdoors during both summer and winter. The most severe contamination occurred in the kitchen in the winter, where the daily mean concentrations of pPAHs, nPAHs, and oPAHs were 7500 ± 4100, 38 ± 29, and 8400 ± 9200 ng/m(3), respectively. Our results suggest that the nPAHs were largely from secondary formation in ambient air while oPAHs were either from primary emission of biomass burning or secondary formation from pPAHs in the kitchen. The daily mean benzo(a)pyrene equivalent exposure concentration was as high as 200 ± 160 ng/m(3) in the winter for the housewife who did the cooking compared to 59 ± 37 ng/m(3) for the control group that did not cook.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Exposição por Inalação , Hidrocarbonetos Policíclicos Aromáticos/análise , Saúde da População Rural , Adulto , China , Culinária , Feminino , Habitação , Humanos , Pessoa de Meia-Idade , Estações do Ano , Cônjuges
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