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1.
Sci Signal ; 16(814): eadi8645, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-38051778

RESUMO

Septin proteins are involved in diverse physiological functions, including the formation of specialized cytoskeletal structures. Septin 8 (Sept8) is implicated in spine morphogenesis and dendritic branching through palmitoylation. We explored the role and regulation of a Sept8 variant in human neural-like cells and in the mouse brain. We identified Sept8-204 as a brain-specific variant of Sept8 that was abundant in neurons and modified by palmitoylation, specifically at Cys469, Cys470, and Cys472. Sept8-204 palmitoylation was mediated by the palmitoyltransferase ZDHHC7 and was removed by the depalmitoylase PPT1. Palmitoylation of Sept8-204 bound to F-actin and induced cytoskeletal dynamics to promote the outgrowth of filopodia in N2a cells and the arborization of neurites in hippocampal neurons. In contrast, a Sept8-204 variant that could not be palmitoylated because of mutation of all three Cys residues (Sept8-204-3CA) lost its ability to bind F-actin, and expression of this mutant did not promote morphological changes. Genetic deletion of Sept8, Sept8-204, or Zdhhc7 caused deficits in learning and memory and promoted anxiety-like behaviors in mice. Our findings provide greater insight into the regulation of Sept8-204 by palmitoylation and its role in neuronal morphology and function in relation to cognition.


Assuntos
Actinas , Septinas , Animais , Humanos , Camundongos , Actinas/genética , Ansiedade/genética , Neurônios/fisiologia , Pseudópodes/genética , Septinas/genética , Septinas/metabolismo , Aprendizagem
2.
Plants (Basel) ; 12(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38140408

RESUMO

Actinidia chinensis Planch. is a fruit tree originating from China that is abundant in the wild. Actinidia eriantha Benth. is a type of A. chinensis that has emerged in recent years. The shape of A. eriantha is an elongated oval, and the skin is covered with dense, non-shedding milk-white hairs. The mature fruit has flesh that is bright green in colour, and the fruit has a strong flavour and a grass-like smell. It is appreciated for its rich nutrient content and unique flavour. Vitamin C, sugar, and organic acids are key factors in the quality and flavour composition of A. eriantha but have not yet been systematically analysed. Therefore, we sequenced the transcriptome of A. eriantha at three developmental stages and labelled them S1, S2, and S3, and comparisons of S1 vs. S2, S1 vs. S3, and S2 vs. S3 revealed 1218, 4019, and 3759 upregulated differentially expressed genes and 1823, 3415, and 2226 downregulated differentially expressed genes, respectively. Furthermore, the upregulated differentially expressed genes included 213 core genes, and Gene Ontology enrichment analysis showed that they were enriched in hormones, sugars, organic acids, and many organic metabolic pathways. The downregulated differentially expressed genes included 207 core genes, which were enriched in the light signalling pathway. We further constructed the metabolic pathways of sugars, organic acids, and vitamin C in A. eriantha and identified the genes involved in vitamin C, sugar, and organic acid synthesis in A. eriantha fruits at different stages. During fruit development, the vitamin C content decreased, the carbohydrate compound content increased, and the organic acid content decreased. The gene expression patterns were closely related to the accumulation patterns of vitamin C, sugars, and organic acids in A. eriantha. The above results lay the foundation for the accumulation of vitamin C, sugars, and organic acids in A. eriantha and for understanding flavour formation in A. eriantha.

3.
Poult Sci ; 102(4): 102539, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36805399

RESUMO

Avian neurotropic viruses are critical problems in poultry industry causing severe central nervous system (CNS) damage with neuroinvasive and neurovirulence properties. Biomarker of neurotropic viral intracranial invasion is of great application value for the diagnosis, but that of avian neurotropic viruses remains elusive. Previously, we found that chicken caspase recruitment domain family, member 11 (CARD11) was only upregulated in virulent Newcastle disease virus-infected chickens and in chicken primary neuronal cells. In this study, CARD11 was systemically expressed in chickens and pigeons detected by absolute qPCR and immunohistochemical (IHC) assay. After virus challenging, only avian neurotropic viruses (avian encephalomyelitis virus [AEV] and pigeon paramyxovirus type 1 [PPMV-1]) except Marek's disease virus (MDV) can invade brain and cause pathological changes. The relative mRNA expression of CARD11 was brain-upregulated in AEV- or PPMV-1-infected animals, rather than MDV and non-neurotropic viruses (fowl adenovirus serotype 4 [FAdV-4] and infectious bronchitis virus [IBV]). Similarly, the protein expression of CARD11 was only upregulated in the cerebra and cerebella infected by avian brain-neurotropic virus using IHC assay. And there were no correlations between the change level of CARD11 and viral load. Our preliminary data suggested that avian CARD11 may be a potential brain biomarker for avian brain-neurotropic virus invasion.


Assuntos
Herpesvirus Galináceo 2 , Doenças das Aves Domésticas , Viroses , Animais , Galinhas/genética , Regulação para Cima , Vírus da Doença de Newcastle , Encéfalo , Viroses/veterinária , Biomarcadores , Doenças das Aves Domésticas/patologia
4.
Cell Death Dis ; 13(9): 786, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36097267

RESUMO

The dynamics of synaptic vesicles (SVs) within presynaptic domains are tightly controlled by synapsin1 phosphorylation; however, the mechanism underlying the anchoring of synapsin1 with F-actin or SVs is not yet fully understood. Here, we found that Syn1 is modified with protein palmitoylation, and examining the roles of Syn1 palmitoylation in neurons led us to uncover that Syn1 palmitoylation is negatively regulated by its phosphorylation; together, they manipulate the clustering and redistribution of SVs. Using the combined approaches of electron microscopy and genetics, we revealed that Syn1 palmitoylation is vital for its binding with F-actin but not SVs. Inhibition of Syn1 palmitoylation causes defects in SVs clustering and a reduced number of total SVs in vivo. We propose a model in which SVs redistribution is triggered by upregulated Syn1 phosphorylation and downregulated Syn1 palmitoylation, and they reversibly promote SVs clustering. The crosstalk of Syn1 palmitoylation and phosphorylation thereby bidirectionally manipulates SVs dynamics in neurons.


Assuntos
Lipoilação , Vesículas Sinápticas , Actinas/metabolismo , Neurônios/metabolismo , Fosforilação , Vesículas Sinápticas/metabolismo
5.
Poult Sci ; 101(5): 101797, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35358926

RESUMO

The purpose of this study was to investigate whether in ovo feeding of t10,c12-conjugated linoleic acid (CLA) could regulate hepatic lipid metabolism and decrease lipid accumulation in newly hatched chicks. Three hundred and sixty fertilely specific pathogen-free hatching eggs were selected and randomly divided into 6 groups. On embryonic day 11 of incubation (E11), 0, 1.5, 3.0, 4.5, 6.0, or 7.5 mg t10,c12-CLA were injected into the eggs. The results indicated that in ovo feeding of t10,c12-CLA significantly decreased the subcutaneous adipose tissue (SAT) mass and the relative SAT weight of newly hatched chicks in linear and quadratic manners (P < 0.05). In liver, the levels of triglycerides were reduced linearly and quadratically and total cholesterol were reduced quadratically as the dose of t10,c12-CLA increased (P < 0.05). Meanwhile, the hepatic carnitine palmitoyltransferase-1a (CPT1a) content and polyunsaturated fatty acid proportion were increased quadratically in t10,c12-CLA groups (P < 0.05), accompanied by the decrease of malondialdehyde level and the increase of glutathione peroxidase and total antioxidant capacity activities (P < 0.05). In addition, in ovo feeding of t10,c12-CLA decreased the mRNA expression levels of fatty acid synthase, acetyl-CoA carboxylase 1 in linear and quadratic manners (P < 0.05), and decreased the mRNA expression of adipose triacylglyceride lipase and stearoyl-CoA desaturase significantly in liver (P < 0.05), accompanied by upregulating the mRNA expression of CPT1a quadratically and AMP-activated protein kinase α linearly and quadratically (P < 0.05). In SAT, the mRNA expression of peroxisome proliferator-activated receptor γ (PPARγ) and sterol regulatory element-binding protein-1c were decreased linearly and quadratically (P < 0.05), and the expression of PPARα and CPT1a genes were increased linearly and quadratically as the dose of t10,c12-CLA increased (P < 0.05). In conclusion, our findings demonstrate that in ovo feeding of t10,c12-CLA alleviates lipid accumulation in newly hatched chicks by suppressing fatty acid synthesis and stimulating lipolysis in the liver and inhibiting adipocyte differentiation in subcutaneous adipose tissue.


Assuntos
Ácidos Linoleicos Conjugados , Tecido Adiposo/metabolismo , Animais , Galinhas/genética , Ácidos Linoleicos Conjugados/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Óvulo/metabolismo , RNA Mensageiro/genética , Gordura Subcutânea/metabolismo
6.
Br J Nutr ; 127(10): 1443-1454, 2022 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33658091

RESUMO

This experiment was designed to investigate the effect of supplementing conjugated linoleic acid (CLA) in breeder hens diet on development and hepatic lipid metabolism of chick offspring. Hy-Line Brown breeder hens were allocated into two groups, supplemented with 0 (control (CT)) or 0·5 % CLA for 8 weeks. Offspring chicks were grouped according to the mother generation and fed for 7 d. CLA treatment had no significant influence on development, egg quality and fertility of breeder hens but darkened the egg yolks in shade and increased yolk sac mass compared with the CT group. Addition of CLA resulted in increased body mass and liver mass and decreased deposition of subcutaneous adipose tissue in chick offspring. The serum TAG and total cholesterol levels of chick offspring were decreased in CLA group. CLA treatment increased the incorporation of both CLA isomers (c9t11 and t10c12) in the liver of chick offspring, accompanied by the decreased hepatic TAG levels, related to the significant reduction of fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) enzyme activities and the increased carnitine palmitoyltransferase-1 (CPT1) enzyme activity. Meanwhile, CLA treatment reduced the mRNA expression of genes related to fatty acid biosynthesis (FAS, ACC and sterol regulatory element-binding protein-1c) and induced the expression of genes related to ß-oxidative (CPT1, AMP-activated protein kinase and PPARα) in chick offspring liver. In summary, the addition of CLA in breeder hens diet significantly increased the incorporation of CLA in the liver of chick offspring, which further regulate hepatic lipid metabolism.


Assuntos
Ácidos Linoleicos Conjugados , Animais , Galinhas/metabolismo , Dieta/veterinária , Ácido Graxo Sintases/metabolismo , Feminino , Ácidos Linoleicos Conjugados/metabolismo , Ácidos Linoleicos Conjugados/farmacologia , Metabolismo dos Lipídeos , Fígado/metabolismo
7.
Front Plant Sci ; 12: 633333, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33815441

RESUMO

Dendrobium candidum is used as a traditional Chinese medicine and as a raw material in functional foods. D. candidum stems are green or red, and red stems are richer in anthocyanins. Light is an important environmental factor that induces anthocyanin accumulation in D. candidum. However, the underlying molecular mechanisms have not been fully unraveled. In this study, we exposed D. candidum seedlings to two different light intensities and found that strong light increased the anthocyanin content and the expression of genes involved in anthocyanin biosynthesis. Through transcriptome profiling and expression analysis, we identified a WD40-repeat transcription factor, DcTTG1, whose expression is induced by light. Yeast one-hybrid assays showed that DcTTG1 binds to the promoters of DcCHS2, DcCHI, DcF3H, and DcF3'H, and a transient GUS activity assay indicated that DcTTG1 can induce their expression. In addition, DcTTG1 complemented the anthocyanin deficiency phenotype of the Arabidopsis thaliana ttg1-13 mutant. Collectively, our results suggest that light promotes anthocyanin accumulation in D. candidum seedlings via the upregulation of DcTTG1, which induces anthocyanin synthesis-related gene expression.

8.
Plant Physiol Biochem ; 162: 603-612, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33774465

RESUMO

Dendrobium candidum stems are used as Chinese medicine and functional food. Red stems of D. candidum are rich in anthocyanins, which attract pollinator insects, protect the plants against environmental stress, and improve human health. The regulatory mechanisms of anthocyanin biosynthesis and stem color differentiation in D. candidum are not fully understood. Using transcriptome profiling, we identified a basic helix-loop-helix transcription factor (DcTT8) involved in anthocyanin biosynthesis in D. candidum stems. Ultraperformance liquid chromatography-tandem mass spectrometry was used to determine pigment contents and compositions in red and green stems, revealing that cyanidin is responsible for the red color. DcTT8 could bind the DcF3'H and DcUFGT promoters and finely regulate DcF3'H and DcUFGT expression. Our data indicate that DcTT8 participates in anthocyanin biosynthesis and offers novel insights into the transcriptional regulation of anthocyanin biosynthesis in D. candidum.


Assuntos
Antocianinas , Dendrobium , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Dendrobium/genética , Dendrobium/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
9.
Panminerva Med ; 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32608212

RESUMO

BACKGROUND: Endoplasmic reticulum stress (ERS) is a newly discovered pathway that causes apoptosis. At present, there is little research about the non-steroidal anti-inflammatory drug (NSAID) on the apoptosis of chondrocytes CHs.Our study aimed to test the anti-apoptosis effects of pranoprofen (PF), a specific prostaglandin E2 (PGE2) inhibitor, on human CHs. METHODS: We firstly made a distinguish about the levels of PGE2, ERS, andapoptosis between cartilage with and without OA. Then CHs isolated from healthy cartilage were pretreated H2O2 or Tunicamycin (TM) to activate ERS, and then exposed to PF. Expression of type II collagen, Runx-2, COX-9, SOD1, GPX1, GRP78, CHOP, caspase-12, ROS level, and apoptosis cell ratio was determined by immunofluorescence, Western blot, RT-PCR, or flow cytometry respectively. RESULTS: We found that oxidative stress, PGE2, ERS, and apoptosis were upregulated in OA cartilage. In addition, H2O2 and TM could increase the levels of PGE2, GRP78, CHOP, caspase-12, and reactive oxygen species (ROS), resulting in the degeneration of CHs. PF significantly reduced the expression of PGE2 and suppressed the ERS and apoptosis caused by H2O2 and TM, showing a protective function of CHs degeneration. CONCLUSIONS: This study demonstrates the anti-apoptotic effect of PF in the abrogation of the ERS-mediated apoptosis in human CHs, suggesting a new mechanism of PF in the treatment of OA.

10.
Poult Sci ; 99(1): 224-234, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32416806

RESUMO

The effects of maternal conjugated linoleic acid (CLA) on embryonic development and hepatic lipid metabolism were investigated in chick embryos. A total of 180 Arbor Acres female broiler breeders (36 wk old) were randomly divided into the following 3 dietary treatment groups: a basic diet (control), a basic diet containing 0.5% CLA (CLA1), and a basic diet containing 1.0% CLA (CLA2). The females were fed for 8 wk, and the eggs from each group were collected and hatched during the last 2 wk. The results showed that the addition of dietary CLA increased the broken egg rate and reduced the fertilization rate and the egg hatchability (P < 0.05). CLA enrichment decreased the polyunsaturated and monounsaturated fatty acids and increased the saturated fatty acids in the yolk sac (P < 0.05). The yolk sac weight, body weight, and body length had a linear decrease with CLA supplementation (P < 0.05). In the developing chick embryo (at E14) and newly hatched chick (D0), the serum triglyceride concentration decreased with maternal CLA supplementation and was accompanied by a reduction in subcutaneous adipose tissue deposition. In addition, maternal CLA supplementation mediated the hepatic lipid metabolism by decreasing the mRNA expression of sterol regulatory element-binding proteins-1c (SREBP-1c), fatty acid synthase and acetyl-CoA carboxylase, and increasing the mRNA expression of adenosine 5'-monophosphate-activated protein kinase α (AMPKα), peroxisome proliferator-activated receptors α (PPARα), liver fatty acid-binding protein, adipose triglyceride lipase and carnitine palmitoyltransferase in embryonic chick livers (P < 0.05). A drop in SREBP-1c protein expression and an increase in the protein expression of p-AMPKα and PPARα were also observed in the liver of chick embryo (P < 0.05). In conclusion, maternal CLA supplementation regulated the fatty acid composition in the yolk sac, and mediated embryonic chick development and hepatic lipometabolism, and these effects may be related to the AMPK pathway. These findings suggest the potential ability of maternal CLA supplementation to reduce fat deposition in chick embryos.


Assuntos
Embrião de Galinha/metabolismo , Ácidos Linoleicos Conjugados/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Ração Animal/análise , Animais , Embrião de Galinha/crescimento & desenvolvimento , Galinhas/metabolismo , Dieta/veterinária , Casca de Ovo , Feminino , Fertilização/efeitos dos fármacos , Fígado/metabolismo , Óvulo , Transdução de Sinais
11.
Curr Mol Med ; 19(5): 364-375, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30914023

RESUMO

BACKGROUND: The homeostasis of palmitoylation and depalmitoylation is involved in various cellular processes, the disruption of which induces severe physiological consequences. Acyl-protein thioesterase (APT) and palmitoyl-protein thioesterases (PPT) catalyze the depalmitoylation process. The natural mutation in human PPT1 caused neurodegenerative disease, yet the understanding of APT1 remains to be elucidated. While the deletion of APT1 in mice turned out to be potentially embryonically lethal, the decoding of its function strictly relied on the identification of its substrates. OBJECTIVE: To determine the potential substrates of APT1 by using the generated human APT1 knockout cell line. METHODS: The combined techniques of palmitoyl-protein enrichment and massspectrometry were used to analyze the different proteins. Palmitoyl-proteins both in HEK293T and APT1-KO cells were extracted by resin-assisted capture (RAC) and data independent acquisition (DIA) quantitative method of proteomics for data collection. RESULTS: In total, 382 proteins were identified. The gene ontology classification segregated these proteins into diverse biological pathways e.g. endoplasmic reticulum process and ubiquitin-mediated proteolysis. A few potential substrates were selected for verification; indeed, major proteins were palmitoylated. Importantly, their levels of palmitoylation were clearly changed in APT1-KO cells. Interestingly, the proliferation of APT1-KO cells escalated dramatically as compared to that of the WT cells, which could be rescued by APT1 overexpression. CONCLUSION: Our study provides a large scale of potential substrates of APT1, thus facilitating the understanding of its intervened molecular functions.


Assuntos
Tioléster Hidrolases/metabolismo , Linhagem Celular , Proliferação de Células , Células Cultivadas , Biologia Computacional/métodos , Retículo Endoplasmático/metabolismo , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Redes Reguladoras de Genes , Células HEK293 , Humanos , Especificidade por Substrato , Tioléster Hidrolases/genética
12.
J Cell Mol Med ; 23(4): 2583-2594, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30680919

RESUMO

Oligoasthenozoospermia is a major cause of male infertility; however, its etiology and pathogenesis are unclear and may be associated with specific gene abnormalities. This study focused on Tppp2 (tubulin polymerization promoting protein family member 2), whose encoded protein localizes in elongating spermatids at stages IV-VIII of the seminiferous epithelial cycle in testis and in mature sperm in the epididymis. In human and mouse sperm, in vitro inhibition of TPPP2 caused significantly decreased motility and ATP content. Studies on Tppp2 knockout (KO) mice demonstrated that deletion of TPPP2 resulted in male subfertility with a significantly decreased sperm count and motility. In Tppp2-/- mice, increased irregular mitochondria lacking lamellar cristae, abnormal expression of electron transfer chain molecules, lower ATP levels, decreased mitochondrial membrane potential and increased apoptotic index were observed in sperm, which could be the potential causes for its oligoasthenozoospermia phenotype. Moreover, we identified a potential TPPP2-interactive protein, eEf1b (eukaryotic translation elongation factor 1 beta), which plays an important role in protein translation extension. Thus, TPPP2 is probably a potential pathogenic factor in oligoasthenozoospermia. Deficiency of TPPP2 might affect the translation of specific proteins, altering the structure and function of sperm mitochondria, and resulting in decreased sperm count, motility and fertility.


Assuntos
Trifosfato de Adenosina/deficiência , Mitocôndrias/metabolismo , Proteínas do Tecido Nervoso/genética , Oligospermia/genética , Fatores de Alongamento de Peptídeos/genética , Espermatozoides/metabolismo , Reação Acrossômica/genética , Animais , Epididimo/metabolismo , Epididimo/patologia , Feminino , Expressão Gênica , Humanos , Tamanho da Ninhada de Vivíparos , Masculino , Camundongos , Camundongos Knockout , Mitocôndrias/patologia , Proteínas do Tecido Nervoso/deficiência , Oligospermia/metabolismo , Oligospermia/patologia , Fatores de Alongamento de Peptídeos/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Capacitação Espermática/genética , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/patologia , Testículo/metabolismo , Testículo/patologia
13.
Oxid Med Cell Longev ; 2018: 4572893, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30538801

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disease, which is characterized by extracellular senile plaque deposits, intracellular neurofibrillary tangles, and neuronal apoptosis. Amyloid-ß (Aß) plays a critical role in AD that may cause oxidative stress and downregulation of CREB/BDNF signaling. Anti-Aß effect has been discussed as a potential therapeutic strategy for AD. This study aimed to identify the amelioration of procyanidins extracted from lotus seedpod (LSPC) on Aß-induced damage with associated pathways for AD treatment. Rat pheochromocytoma (PC12) cells incubated with Aß 25-35 serve as an Aß damage model to evaluate the effect of LSPC in vitro. Our findings illustrated that LSPC maintained the cellular morphology from deformation and reduced apoptosis rates of cells induced by Aß 25-35. The mechanisms of LSPC to protect cells from Aß-induced damage were based on its regulation of oxidation index and activation of CREB/BDNF signaling, including brain-derived neurotrophic factor (BDNF) and phosphorylation of cAMP-responsive element-binding (CREB), protein kinase B (also known as AKT), and the extracellular signal-regulated kinase (ERK). Of note, by high-performance liquid chromatography-tandem mass spectroscopy (LC-MS/MS), several metabolites were detected to accumulate in vivo, part of which could take primary responsibility for the amelioration of Aß-induced damage on PC12 cells. Taken together, our research elucidated the effect of LSPC on neuroprotection through anti-Aß, indicating it as a potential pretreatment for Alzheimer's disease.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Lotus , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Proantocianidinas/farmacologia , Doença de Alzheimer , Animais , Apoptose/efeitos dos fármacos , Frutas/química , Fármacos Neuroprotetores/química , Células PC12 , Extratos Vegetais/química , Ratos
14.
Photochem Photobiol Sci ; 17(8): 1084-1090, 2018 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-29943790

RESUMO

Bi2WO6 nanosheets were synthesized by a hydrothermal method with H2WO4 for the first time. The band structure of Bi2WO6 was investigated on the basis of density functional theory calculations. Bi2WO6 photocatalysts showed photocatalytic activity for the degradation of methylene blue under visible light irradiation. Kinetic studies using radical scavenger technologies suggested that holes were the dominant photo-oxidants. After hybridization with C3N4, the photocatalytic activity of Bi2WO6 was obviously enhanced. The enhanced photocatalytic activity of the C3N4/Bi2WO6 photocatalysts could be attributed to the effective separation of photogenerated e-/h+ pairs. The photogenerated holes on the valence band of Bi2WO6 can transfer to the highest occupied molecular orbital of C3N4via the well-developed interface, causing a reduction in the probability of e-/h+ recombination; consequently, large numbers of photogenerated holes led to the enhancement of the photocatalytic activity.

15.
Sci Total Environ ; 635: 1360-1366, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29710589

RESUMO

Horizontal subsurface constructed wetlands (HSSF-CWs) planted with Phragmites australis were established to examine the effect of influent nitrogen loads on the removal efficiencies of nitrogen and chemical oxygen demand (COD) during different plant growth periods of plants. Under low influent nitrogen loads, most of the dissolved oxygen was consumed during the oxidation of organic matter in the wetland systems, and a dissimilatory nitrate reduction to ammonium (DNRA) may have occurred in HSSF-CWs when excessive amounts of organic matter were present, which limited the nitrification of ammonium nitrogen (NH4-N) and hindered the NH4-N removal. An increase in the influent nitrogen loads resulted in an enhancement of the removal efficiencies of NH4-N, nitrate nitrogen (NO3-N) and total nitrogen (TN) during the same growth period, except for NO3-N under the highest influent nitrogen loads, whereas fluctuations occurred for the COD removal efficiency. Compared with the rapid growth period, the removal efficiency of NH4-N, NO3-N and TN increased during the mature period; however, the COD removal efficiency decreased. The change of COD: N (COD:TN in wastewater) ratios with retention times indicated the sufficiency or deficiency of organic matter as an electron donor in the wetland systems. The changes in the pH value and oxidation-reduction potential (ORP) indirectly demonstrated that many factors affected the effluent pH value and ORP, such as retention time, influent loads, plants and wetland substrate, and microorganisms. In this study, the changes of ORP also illustrated that the dissolved oxygen concentrations decreased with increasing retention time in the HSSF-CWs; however, no significant increase in the ORP was observed during the two growth periods.

16.
Nanoscale Res Lett ; 13(1): 54, 2018 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-29457198

RESUMO

As the advanced functional materials, silver nanoparticles are potentially useful in various fields such as photoelectric, bio-sensing, catalysis, antibacterial and other fields, which are mainly based on their various properties. However, the properties of silver nanoparticles are usually determined by their size, shape, and surrounding medium, which can be modulated by various synthesis methods. In this review, the fabrication methods for synthesizing silver nanoparticles of different shapes and specific size are illustrated in detail. Besides, the corresponding properties and applications of silver nanoparticles are also discussed in this paper.

17.
J Org Chem ; 82(8): 4444-4448, 2017 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-28362091

RESUMO

An efficient catalyst-, base-, and oxidant-free direct cyanoalkylarylation of isocyanides with AIBN has been developed under mild conditions. This strategy provides an elusive and rapid access to a wide range of cyano-containing phenanthridine derivatives in good yields via a one-pot alkylation/cyclization radical-cascade process. The mild reaction conditions together with no need of any catalyst, base, or oxidant make this protocol environmentally benign and practical.

18.
Angew Chem Int Ed Engl ; 56(12): 3242-3246, 2017 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-28194912

RESUMO

The combination of a transition-metal catalyst and organocatalyst was designed to achieve a highly enantioselective system for the allylic dearomatization reaction of naphthols with racemic secondary allylic alcohols. The desired ß-naphthalenones, bearing an all-carbon quaternary center, were obtained in good yields with high chemo- and enantioselectivities. The cooperative catalytic system, involving a chiral iridium complex and phosphoric acid, provided measurable improvements in yields, and chemo- and enantioselectivities relative to single-catalyst systems. Control experiments indicated that the chiral iridium complex functions as a key species in the control of the absolute configuration, thus enabling the formation of both ß-naphthalenone enantiomers by simply employing opposite enantiomeric ligands.

19.
J Assist Reprod Genet ; 34(4): 535-545, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28116645

RESUMO

PURPOSE: The aim of this study is to evaluate the effect of repeated controlled ovarian hyperstimulation (COH) on the structure and function of the uterus and mammary gland. METHODS: Three adult female rhesus monkeys were superovulated up to four times, and three spontaneously ovulating monkeys were used as controls. After a 5-year period, the uterus and mammary gland tissue samples were collected for examination of their structure and function. Further, the expression of certain tumor markers was examined to assess the cancer risk for each organ. RESULTS: Expression of Wnt7a (associated with the functional/developmental status of the uterus) was significantly decreased in the uterus of superovulated monkeys, and decreased expression of proliferation marker PCNA was found in uterine cells. Meanwhile, abnormal Golgi-derived secretory vesicles with an irregular shape were observed in the mammary glands of the superovulated monkeys, and decreased PCNA expression together with increased expression of caspase-3 (an apoptosis marker) was indicated in the mammary cells. The expression of tumor molecular markers of the uterus and mammary gland was not significantly different between the two groups. CONCLUSIONS: Repeated COH affects the expression of the uterine development-related gene several years later, and uterine cells exhibited a low proliferation status. The ultrastructure of the mammary gland epithelial cells was abnormal, and the cells exhibited both low proliferation and high apoptosis status. Cancer risk for these organs was not observed. Given that primates are the closest relatives of humans, the results obtained from this study provide more intuitive information for optimization of clinical COH.


Assuntos
Biomarcadores Tumorais/genética , Glândulas Mamárias Animais/metabolismo , Indução da Ovulação/efeitos adversos , Superovulação , Útero/metabolismo , Animais , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/genética , Caspase 3/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Macaca mulatta , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/patologia , Neoplasias Ovarianas/induzido quimicamente , Neoplasias Ovarianas/genética , Antígeno Nuclear de Célula em Proliferação/genética , Fatores de Risco , Útero/efeitos dos fármacos , Útero/patologia , Proteínas Wnt/genética
20.
Asian-Australas J Anim Sci ; 30(3): 417-423, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27383812

RESUMO

OBJECTIVE: This experiment investigated the effects of dietary supplementation with conjugated linoleic acid (CLA) on the serum components, laying hen productivity, lipid composition of egg yolk, egg flavor and egg quality. METHODS: Healthy 28-week-old Hy-Line white laying hens (n = 480) were divided randomly into 4 groups, 6 replicates/group, 20 birds/replicate. The 30-day experimental diets included 0% (control), 0.4%, 0.8%, and 1.6% CLA. Some serum indices of the birds, and egg production, quality, fatty acid composition, egg quality were measured. RESULTS: The dietary supplementation with 0.4%, 0.8%, and 1.6% CLA did not significantly affect the laying rate and feed intake, as well as calcium ion and phosphorus ion concentration in serum (p>0.05). However, the CLA had significantly increased the strength of eggshell, decreased the odor, flavor, and taste of egg yolk, deepened the color of egg yolk, increased saturated fatty acids and polyunsaturated fatty acids, and reduced the monounsaturated fatty acids (p<0.05). On the other hand, the dietary supplementation with 1.6% CLA had significant effects on feed/gain, and improved serum hormones. Dietary supplementation with 0.4% and 0.8% CLA can significantly enhance the activity of alkaline phosphates. CONCLUSION: CLA has no effect on production performance, but does enhance the lipid content of the egg yolk and the strength of the eggshell.

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