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1.
Ecotoxicol Environ Saf ; 281: 116671, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38959788

RESUMO

BACKGROUND: With the advancement of medical technology, tools such as electrosurgical equipment, laser knives, and ultrasonic scalpels have made modern medical procedures more convenient and effective. However, the generation of surgical smoke during these procedures poses significant health risks to medical personnel. Despite this, only a few studies have examined the literature systematically in this area. By analyzing bibliometric data on surgical smoke, we can gain insights into current research hotspots and forecast future trends. METHODS: This study included literature related to surgical smoke from the Web of Science and China National Knowledge Infrastructure (CNKI) databases, covering the period from 2000 to 2024. We used VOSviewer, CiteSpace, and BioBERT to visualize research trends and hotspots. RESULTS: In the early stages of research, the focus was mainly on the composition, generation mechanisms, and susceptible populations related to surgical smoke. In recent years, with the development of laparoscopic surgery and the global COVID-19 pandemic, research interests have shifted towards occupational protection of healthcare workers and public health. Currently, the research in this field primarily explores the promoting effects of surgical smoke on conditions such as inflammation and tumors, as well as occupational protection and health education for healthcare workers. Disease research focuses heavily on Smoke Inhalation Injury, Infections, Neoplasms, Postoperative Complications, and Inflammation. CONCLUSION: We explored future research directions in the field of surgical smoke using VOSviewer, CiteSpace, and BioBERT. Our findings indicate that current research focuses on investigating the promoting effects of surgical smoke on conditions such as inflammation and tumors, as well as on occupational protection and health education for healthcare workers. We summarized existing preventive measures, aiming to facilitate further research advancements and the translation of research outcomes into clinical results. These efforts provide new insights for advancing research in occupational protection of healthcare workers.


Assuntos
Exposição Ocupacional , Fumaça , Humanos , Bibliometria , China , Pessoal de Saúde/estatística & dados numéricos , Fumaça/efeitos adversos
2.
Angew Chem Int Ed Engl ; 63(16): e202318589, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38385612

RESUMO

Catalyst surface dynamics drive the generation of active species for electrocatalytic reactions. Yet, the understanding of dominant site formation and reaction mechanisms is limited. In this study, we thoroughly investigate the dynamic reconstruction of two-dimensional defective Bi nanosheets from exfoliated Bi2Se3 nanosheets under electrochemical CO2 and nitrate (NO3 -) reduction conditions. The ultrathin Bi2Se3 nanosheets obtained by NaBH4-assisted cryo-mediated liquid-phase exfoliation are more easily reduced and reconstructed to Bi nanosheets with high-density grain boundaries (GBs; GB-rich Bi). The reconstructed GB-rich Bi catalyst affords a remarkable yield rate of 4.6 mmol h-1 mgcat. -1 and Faradaic efficiency of 32 % for urea production at -0.40 V vs. RHE. Notably, this yield rate is 2 and 8.2 times higher than those of the low-GB Bi and bulk Bi catalysts, respectively. Theoretical analysis demonstrates that the GB sites significantly reduce the *CO and *NH2 intermediate formation energy and C-N coupling energy barrier, enabling selective urea electrosynthesis on the GB-rich Bi catalyst. This work will trigger further research into the structure-activity interplay in dynamic processes using in situ techniques.

3.
Small ; 19(26): e2302295, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37194952

RESUMO

Although the electrocatalytic nitrate reduction reaction (NO3 - RR) is an attractive NH3 synthesis route, it suffers from low yield due to the lack of efficient catalysts. Here, this work reports a novel grain boundary (GB)-rich Sn-Cu catalyst, derived from in situ electroreduction of Sn-doped CuO nanoflower, for effectively electrochemical converting NO3 - to NH3 . The optimized Sn1% -Cu electrode achieves a high NH3 yield rate of 1.98 mmol h-1 cm-2 with an industrial-level current density of -425 mA cm-2 at -0.55 V versus a reversible hydrogen electrode (RHE) and a maximum Faradaic efficiency of 98.2% at -0.51 V versus RHE, outperforming the pure Cu electrode. In situ Raman and attenuated total reflection Fourier transform infrared spectroscopies reveal the reaction pathway of NO3 - RR to NH3 by monitoring the adsorption property of reaction intermediates. Density functional theory calculations clarify that the high-density GB active sites and the competitive hydrogen evolution reaction (HER) suppression induced by Sn doping synergistically promote highly active and selective NH3 synthesis from NO3 - RR. This work paves an avenue for efficient NH3 synthesis over Cu catalyst by in situ reconstruction of GB sites with heteroatom doping.

4.
Opt Express ; 31(15): 23944-23951, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37475234

RESUMO

This study proposes a deep learning architecture for automatic modeling and optimization of multilayer thin film structures to address the need for specific spectral emitters and achieve rapid design of geometric parameters for an ideal spectral response. Multilayer film structures are ideal thermal emitter structures for thermophotovoltaic application systems because they combine the advantages of large area preparation and controllable costs. However, achieving good spectral response performance requires stacking more layers, which makes it more difficult to achieve fine spectral inverse design using forward calculation of the dimensional parameters of each layer of the structure. Deep learning is the main method for solving complex data-driven problems in artificial intelligence and provides an efficient solution for the inverse design of structural parameters for a target waveband. In this study, an eight-layer thin film structure composed of SiO2/Ti and SiO2/W is rapidly reverse engineered using a deep learning method to achieve a structural design with an emissivity better than 0.8 in the near-infrared band. Additionally, an eight-layer thin film structure composed of 3 × 3 cm SiO2/Ti is experimentally measured using magnetron sputtering, and the emissivity in the 1-4 µm band was better than 0.68. This research provides implications for the design and application of micro-nano structures, can be widely used in the fields of thermal imaging and thermal regulation, and will contribute to developing a new paradigm for optical nanophotonic structures with a fast target-oriented inverse design of structural parameters, such as required spectral emissivity, phase, and polarization.

5.
Ecotoxicol Environ Saf ; 237: 113511, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35489137

RESUMO

Sphingosine kinase 1 (SphK1) is an important signaling molecule for cell proliferation and survival. However, the role of SphK1 in acrylamide (ACR)-induced nerve injury remains unclear. The purpose of this study was to investigate the role and potential mechanism of SphK1 in ACR-induced nerve injury. Liquid chromatography triple quadrupole tandem mass spectrometry (LC-MS/MS) and reverse transcription-quantitative PCR (RT-qPCR) were used to detect sphingosine 1-phosphate (S1P) content in serum and SphK1 content in whole blood from an occupational work group exposed to ACR compared to a non-exposed group. For in vitro experiments, SphK1 in human SH-SY5Y neuroblastoma cells was activated using SphK1-specific activator phorbol 12-myristate 13-acetate (PMA). Our research also utilized cell viability assays, flow cytometry, western blots, RT-qPCR and related protein detection to assess activity of the mitogen activated protein kinase (MAPK) signaling pathway. The results of the population study showed that the contents of SphK1 and S1P in the ACR-exposed occupational contact group were lower than in the non-exposed group. The results of in vitro experiments showed that expression of SphK1 decreased with the increase in ACR concentration. Activating SphK1 improved the survival rate of SH-SY5Y cells and decreased the apoptosis rate. Activating SphK1 in SH-SY5Y cells also regulated MAPK signaling, including enhancing the phosphorylation of extracellular signal-regulated protein kinases (ERK) and inhibiting the phosphorylation of c-Jun N-terminal kinase (JNK) and p38. These results suggest that activating SphK1 can protect against nerve cell damage caused by ACR.


Assuntos
Acrilamida , Espectrometria de Massas em Tandem , Acrilamida/toxicidade , Cromatografia Líquida , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Neurônios/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)
6.
Nanotechnology ; 32(28)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33765662

RESUMO

The oxygen evolution reaction (OER) is a process in electrochemical water splitting with sluggish kinetics that needs efficient non-noble-metal electrocatalysts. There have been few studies of CrOOH electrocatalysts for water oxidation due to their low performance. Herein,in situsynthesized Fe-doped CrOOH nanosheets on Ni foam (Fe-CrOOH/NF) were designed as electrocatalysts and performance in the OER was obviously improved. The effect of the amount of Fe doping was also investigated. Experiments revealed that the best performance of Fe-CrOOH/NF requires low overpotentials of 259 mV to reach 20 mA cm-2together with a turnover frequency of 0.245 s-1in 1.0 M KOH, which may suggest a new direction for the development of Fe-doped OER electrocatalysts.

7.
Phytother Res ; 35(1): 346-360, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32749748

RESUMO

Aurantio-obtusin (AUR) is the main bioactive compound among the anthraquinones, from Cassia seed extract. This study was conducted to identify whether AUR could improve obesity and insulin resistance, induced by a high-fat diet in obese mice. Mice were fed a high-fat diet for 6 weeks and were then assigned to the high-fat diet (HFD) control group, the AUR 5 mg/kg group, or the AUR 10 mg/kg group. AUR improves glucose by activating the expression of PI3K, Akt and GLUT4, GLUT2. AUR altered the expression levels of several lipid metabolism-related and adipokine genes. AUR decreased the mRNA expression of PPAR-γ, FAS and increased the mRNA expression of PPAR-α in liver. AUR lowered SREBP-1c, FAS, SCD-1, inflammatory cytokines, and increased the expression of PPAR-γ, PPAR-α, CPT-1, and adiponectin in white adipose tissue (WAT). AUR docking with the insulin receptor showed that the residues of the insulin receptor, ectodomain, were the same as those around the emodin. The effect of AUR may be elicited by regulating the activity of the insulin signaling pathway, expression of lipid metabolism-related genes, and expression of inflammatory cytokine markers to improve adiposity, insulin resistance, and dyslipidemia.


Assuntos
Antraquinonas/uso terapêutico , Resistência à Insulina , Obesidade/tratamento farmacológico , Adiponectina/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Cassia/química , Dieta Hiperlipídica , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/metabolismo , PPAR gama/metabolismo , Receptor de Insulina/metabolismo , Sementes/química , Transdução de Sinais/efeitos dos fármacos , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
8.
Arch Biochem Biophys ; 681: 108279, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31982394

RESUMO

Because long-term occupational exposure to low concentrations of acrylamide (ACR) has the potential to cause neurological damage, it is important to identify biomarkers that can be used to evaluate this risk. In the present study, urine metabolomics of the ACR-exposed and non-exposed groups to identify potential metabolites was carried out using ultra high performance liquid chromatography coupled with quadrupole time of flight mass spectrometry. Serum biochemical indexes of the exposed and non-exposed groups were also determined. Principal component analysis showed a differential separation between exposed group and non-exposed group and a total of 7 metabolites were identified in positive and negative ionization modes; Area under curve of anthranilic acid, ß-guanidinopropionic acid and mesobilirubinogen were 0.980, 0.843 and 0.801 respectively and these metabolites showed high sensitivity and specificity. The 13 biochemical indexes were divided into three classes based on physiological functions. Only biomarkers of dysregulated liver function including alanine aminotransferase, aspartic transaminase, total bilirubin, direct bilirubin and triglyceride were significantly higher in the exposed group than in the non-exposed group. This study identifies important related metabolic changes in the bodies of workers after long-term occupational exposure to low concentration ACR and suggests new biomarkers of nervous system injury caused by ACR. The study also provides a sound basis for exploring the biochemical mechanisms and metabolic pathways of nervous system toxicity caused by ACR.


Assuntos
Acrilamida/efeitos adversos , Biomarcadores/urina , Metabolômica/métodos , Exposição Ocupacional/efeitos adversos , Acrilamida/metabolismo , Adulto , Biomarcadores/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem/métodos , Urinálise/métodos
9.
Arch Biochem Biophys ; 660: 20-28, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30321500

RESUMO

Nickel (Ni) is widely present in the occupational environment and causes various adverse effects on the human body. Apoptosis induced by Ni2+ may be a key mechanism underlying its toxic effect. In the present study, we investigated the effect of Ni-smelting fumes on cell viability, mitochondrial damage, and apoptosis-related proteins in NIH/3T3 cells. The effects of Ni-smelting fumes at concentrations of 0, 25, 50, and 100 µg/mL were tested. Treatment with Ni-smelting fumes for 24 h and 48 h significantly decreased cell viability and lactate dehydrogenase activity in a dose- and time-dependent manner compared with the blank control group. Exposure to Ni-smelting fumes increased mitochondrial permeability transition pore opening in a dose-dependent manner and decreased mitochondrial membrane potential and the activity of the mitochondrial respiratory chain complexes I, II, and IV. The fumes significantly downregulated Bcl-2, procaspase-9, and procaspase-3 and upregulated Bax, caspase-9, and caspase-3 (P < 0.05). Ni-smelting fumes caused significant cytotoxicity, oxidative stress, mitochondrial damage, and apoptosis through the intrinsic pathway in mammalian cells. The present paper provides hypotheses and experimental support for these hypotheses that Ni-smelting fumes cause cytotoxicity through the mechanism of inducing mitochondrial damage and apoptosis in NIH/3T3 cells.


Assuntos
Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Níquel/toxicidade , Animais , Caspases/metabolismo , Regulação para Baixo/efeitos dos fármacos , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , L-Lactato Desidrogenase/metabolismo , Camundongos , Células NIH 3T3 , Níquel/química , Exposição Ocupacional/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo
10.
Int J Mol Sci ; 19(7)2018 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-30029529

RESUMO

Mytilus edulis is a typical marine bivalve mollusk. Many kinds of bioactive components with nutritional and pharmaceutical activities in Mytilus edulis were reported. In this study, eight different parts of Mytilus edulis tissues, i.e., the foot, byssus, pedal retractor muscle, mantle, gill, adductor muscle, viscera, and other parts, were separated and the proteins from these tissues were prepared. A total of 277 unique peptides from the hydrolysates of different proteins were identified by UPLC-Q-TOF-MS/MS, and the molecular weight distribution of the peptides in different tissues was investigated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The bioactivity of the peptides was predicted through the Peptide Ranker database and molecular docking. Moreover, the peptides from the adductor muscle were chosen to do the active validation of anticoagulant activity. The active mechanism of three peptides from the adductor muscle, VQQELEDAEERADSAEGSLQK, RMEADIAAMQSDLDDALNGQR, and AAFLLGVNSNDLLK, were analyzed by Discovery Studio 2017, which also explained the anticoagulant activity of the hydrolysates of proteins from adductor muscle. This study optimized a screening and identification method of bioactive peptides from enzymatic hydrolysates of different tissues in Mytilus edulis.


Assuntos
Anticoagulantes/metabolismo , Simulação por Computador , Mytilus edulis/metabolismo , Peptídeos/metabolismo , Proteínas/metabolismo , Tripsina/metabolismo , Sequência de Aminoácidos , Animais , Anticoagulantes/química , Hidrólise , Simulação de Acoplamento Molecular , Especificidade de Órgãos , Peptídeos/química , Solubilidade
11.
Int J Mol Sci ; 19(2)2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-29425186

RESUMO

The effects of ball mill treatment (0, 2, 4, 6, 8, and 10 min) on the physicochemical and digestible properties of scallops (Chlamys farreri) protein (CFP) were investigated. The CFP particle size decreased with increasing ball-milling time. The content of free sulfhydryl (SH) of CFP increased from 13.08 ± 0.25 µmol/g protein to 18.85 ± 0.24 µmol/g protein when the ball-milling time increased from 0 min to 10 min. A sharp increase of the surface hydrophobicity index (H0) from 48.53 ± 0.27 to 239.59 ± 0.37 was found when the ball-milling time increased from 0 min to 4 min. Furthermore, the foaming capacity increased from 46.08 ± 6.12% to 65.11 ± 1.05% with increasing ball-milling time from 0 min to 6 min, after which it reached a plateau. SDS-PAGE results showed that ball mill treatment did not change the primary structure of CFP. Digestible properties of BMCFP simulated gastrointestinal digestion as a function of ball mill treatment were analyzed by Tricine-SDS-PAGE and nitrogen recovery index. After 60 min of simulated human gastro digestion, nitrogen recovery index of CFP had a significant rise from 42.01 ± 0.31% to 58.78 ± 3.37% as the ball-milling time increased from 0 min to 6 min. Peptides from hydrolysates of Chlamys farreri protein (CFP) were identified by ultraperformance liquidchromatographysystem coupled to a Synapt Mass Quadrupole Time-of-Flight Mass Spectrometer (UPLC-Q-TOF-MS). After 2 h and 4 h of simulated human duodenal digestion, the number of peptides with 7-10 amino acids length increased apparently with the ball-milling time increased. This study presents an approach to investigating the effect of the ball-milling process on the physicochemical and digestible properties of CFP, which may provide valuable information on the application of CFP as an ingredient in food products.


Assuntos
Proteínas Alimentares/química , Manipulação de Alimentos/métodos , Pectinidae/química , Animais , Digestão , Manipulação de Alimentos/instrumentação , Interações Hidrofóbicas e Hidrofílicas , Desnaturação Proteica , Estabilidade Proteica
12.
Molecules ; 23(4)2018 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-29565324

RESUMO

In this study, the effects of limited hydrolysis and/or high-pressure homogenization (HPH) treatment in acid conditions on the functional properties of oyster protein isolates (OPI) were studied. Protein solubility, surface hydrophobicity, particle size distribution, zeta potential, foaming, and emulsifying properties were evaluated. The results showed that acid treatment led to the dissociation and unfolding of OPI. Subsequent treatment such as limited proteolysis, HPH, and their combination remarkably improved the functional properties of OPI. Acid treatment produced flexible aggregates, as well as reduced particle size and solubility. On the contrary, limited hydrolysis increased the solubility of OPI. Furthermore, HPH enhanced the effectiveness of the above treatments. The emulsifying and foaming properties of acid- or hydrolysis-treated OPI significantly improved. In conclusion, a combination of acid treatment, limited proteolysis, and HPH improved the functional properties of OPI. The improvements in the functional properties of OPI could potentiate the use of oyster protein and its hydrolysates in the food industry.


Assuntos
Proteínas de Plantas/química , Animais , Concentração de Íons de Hidrogênio , Hidrólise , Ostreidae/química , Solubilidade
13.
Molecules ; 23(5)2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29772679

RESUMO

Ruditapes philippinarum proteins were hydrolyzed by trypsin, neutrase, and pepsin. The antioxidant activities and ACE inhibitory activity of hydrolysates were analyzed and the antioxidant activities were related to their molecular weight distribution and amino acid compositions. Results indicated the hydrolysis of proteins led to an increase in small peptides and free amino acids. The antioxidant activities of Ruditapes philippinarum hydrolysates against DPPH radical scavenging, inhibition on linoleic acid peroxidation, and reducing power showed that the neutrase hydrolysate exhibited the strongest antioxidant activity. In addition, an ACE inhibition assay revealed that the pepsin hydrolysate had the highest ACE inhibitory ability. Ruditapes philippinarum protein hydrolysates could be a promising source of natural antioxidant and ACE inhibitory.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Antioxidantes/farmacologia , Bivalves/metabolismo , Peptídeos/farmacologia , Proteínas/química , Animais , Hidrólise , Ácido Linoleico/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Peso Molecular , Pepsina A/metabolismo
14.
Molecules ; 23(12)2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30563010

RESUMO

The effects of HPH (high-pressure homogenization) pre-treatment on the functional properties of OPIH (oyster protein isolates hydrolysates) were studied. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis profiles, solubility, particle size distribution, zeta potential, surface hydrophobicity, emulsifying activity index and microstructure of emulsions were analyzed. Results indicated that HPH pre-treatment increased the accessibility of OPI to trypsin hydrolysis, resulting in decease in particle size, increase in solubility, absolute zeta potential, surface hydrophobicity and emulsifying activity index. In addition, HPH pre-treated OPIH emulsions became more uniform and the particle size of droplets decreased. These results revealed that HPH pre-treatment has the potential to modify the functional properties of OPIH.


Assuntos
Ostreidae/química , Hidrolisados de Proteína , Proteínas de Frutos do Mar , Animais , Emulsões/química , Tamanho da Partícula , Pressão , Proteínas de Frutos do Mar/química
15.
Fish Shellfish Immunol ; 70: 553-559, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28939529

RESUMO

Cathepsin D (CTSD, EC 3.4.23.5) belongs to aspartic protease family, which is located in lysosomes and is distributed in diverse tissues and cells. CTSD has a wide variety of physiological functions, owing to its proteolytic activity in degradating proteins and peptides. In the current study, the full length cDNA of sea cucumber (Apostichopus japonicus) cathepsin D (AjCTSD) was firstly cloned, then the association between AjCTSD and sea cucumber autolysis was investigated. The full length cDNA of AjCTSD was 2896 bp, with an open reading frame (ORF) for 391 amino acids. AjCTSD was widely expressed in body wall, muscle and intestine; the expression level was the highest in intestine, followed by muscle and body wall. Compared to fresh tissues, AjCTSD expression levels were significantly increased in all examined autolytic tissues. The purified recombinant AjCTSD promoted the degradation of sea cucumber muscle. In conclusion, AjCTSD contributed to sea cucumber muscle autolysis.


Assuntos
Catepsina D/genética , Catepsina D/imunologia , Stichopus/genética , Stichopus/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Catepsina D/química , Clonagem Molecular , DNA Complementar/genética , Perfilação da Expressão Gênica , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Alinhamento de Sequência
16.
J Sci Food Agric ; 97(13): 4604-4611, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28349531

RESUMO

BACKGROUND: Sea cucumber (Stichopus japonicus) ovum hydrolysates (SCOHs) chelated with calcium were produced to investigate the characteristics of calcium binding and solubility, as well as to study any effects on calcium absorption by human intestinal epithelial cells. RESULTS: The results of the present study show that the calcium-binding capacity of SCOHs depended greatly on the type of proteases. The maximum level of Ca binding (0.38 mmol L-1 ) occurred when trypsin was used, with a peptide yield of 85.7%. Investigation of the possible chelating modes between SCOHs and calcium ions indicated that calcium ions bound to SCOHs primarily via interactions with carboxyl oxygen and amino nitrogen atoms of Glu and Asp and also that the phosphoserine residues might be also responsible for SCOH-calcium chelation. Moreover, SCOH-calcium complexes maintained the solubility of calcium under simulated gastrointestinal digestion, regardless of the presence of dietary components such as oxalate. Furthermore, SCOH-Ca led to higher peak intracellular [Ca2+ ]i in both Caco-2 cells (338.3 nmol L-1 versus 269.6 nmol L-1 ) and HT-29 cells (373.9 nmol L-1 versus 271.7 nmol L-1 ) than casein phosphopeptide-Ca. CONCLUSION: Carboxyl oxygen and amino nitrogen atoms in the SCOHs could bind calcium ions, forming SCOH-calcium complexes. These complexes improved calcium solubility under simulated gastrointestinal digestion and also promoted calcium absorption in Caco-2 and HT-29 cells. © 2017 Society of Chemical Industry.


Assuntos
Células Epiteliais/metabolismo , Mucosa Intestinal/metabolismo , Óvulo/química , Hidrolisados de Proteína/química , Stichopus/química , Animais , Células CACO-2 , Cálcio/química , Cálcio/metabolismo , Humanos , Hidrolisados de Proteína/metabolismo , Solubilidade , Stichopus/metabolismo
17.
Arch Biochem Biophys ; 564: 142-55, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25281768

RESUMO

14-3-3γ, an isoform of the 14-3-3 protein family, was proved to be a positive regulator of mTOR pathway. Here, we analyzed the function of 14-3-3γ in protein synthesis using bovine mammary epithelial cells (BMECs). We found that 14-3-3γ interacted with eIF1AX and RPS7 by 14-3-3γ coimmunoprecipitation (CoIP) and matrix-assisted laser desorption/ionization-time-of-flight/time-of-flight (MALDI-TOF/TOF) peptide mass fingerprinting analysis. These interactions of 14-3-3γ with eIF1AX and RPS7 were further confirmed by colocalization and fluorescence resonance energy transfer (FRET) analysis. We also found that methionine could promote protein synthesis and trigger the protein expression levels of 14-3-3γ, eIF1AX and RPS7. Analysis of overexpression and inhibition of 14-3-3γ confirmed that it positively affected the protein expression levels of eIF1AX, RPS7, Stat5 and mTOR pathway to promote protein synthesis and cell proliferation in BMECs. We further showed that overexpression of eIF1AX and RPS7 also triggered protein translation and cell proliferation. From these results, we conclude that molecular network including eIF1AX, RPS7, and 14-3-3γ regulates protein translation and cell proliferation in BMECs.


Assuntos
Proteínas 14-3-3/metabolismo , Proliferação de Células/fisiologia , Células Epiteliais/metabolismo , Fator de Iniciação 1 em Eucariotos/metabolismo , Glândulas Mamárias Animais/metabolismo , Biossíntese de Proteínas/fisiologia , Proteína S6 Ribossômica/metabolismo , Proteínas 14-3-3/genética , Animais , Bovinos , Células Cultivadas , Células Epiteliais/citologia , Fator de Iniciação 1 em Eucariotos/genética , Feminino , Regulação da Expressão Gênica/fisiologia , Humanos , Glândulas Mamárias Animais/citologia , Proteína S6 Ribossômica/genética , Ressonância de Plasmônio de Superfície
18.
Molecules ; 19(7): 9435-52, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24995926

RESUMO

Glycogen synthase kinase 3 (GSK3) is a serine/threonine kinase, whose activity is inhibited by AKT phosphorylation. This inhibitory phosphorylation of GSK3ß can in turn play a regulatory role through phosphorylation of several proteins (such as mTOR, elF2B) to promote protein synthesis. mTOR is a key regulator in protein synthesis and cell proliferation, and recent studies have shown that both GSK3ß and mTORC1 can regulate SREBP1 to promote fat synthesis. Thus far, however, the cross talk between GSK3ß and the mTOR pathway in the regulation of milk synthesis and associated cell proliferation is not well understood. In this study the interrelationship between GSK3ß and the mTOR/S6K1 signaling pathway leading to milk synthesis and proliferation of dairy cow mammary epithelial cells (DCMECs) was analyzed using techniques including GSK3ß overexpression by transfection, GSK3ß inhibition, mTOR inhibition and methionine stimulation. The analyses revealed that GSK3ß represses the mTOR/S6K1 pathway leading to milk synthesis and cell proliferation of DCMECs, whereas GSK3ß phosphorylation enhances this pathway. Conversely, the activated mTOR/S6K1 signaling pathway downregulates GSK3ß expression but enhances GSK3ß phosphorylation to increase milk synthesis and cell proliferation, whereas inhibition of mTOR leads to upregulation of GSK3ß and repression of GSK3ß phosphorylation, which in turn decreases milk synthesis, and cell proliferation. These findings indicate that GSK3ß and phosphorylated GSK3ß regulate milk synthesis and proliferation of DCMECs via the mTOR/S6K1 signaling pathway. These findings provide new insight into the mechanisms of milk synthesis.


Assuntos
Células Epiteliais/enzimologia , Quinase 3 da Glicogênio Sintase/fisiologia , Glândulas Mamárias Animais/citologia , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Bovinos , Proliferação de Células , Células Cultivadas , Células Epiteliais/efeitos dos fármacos , Feminino , Lactação , Cloreto de Lítio/farmacologia , Metionina/farmacologia , Fosforilação , Processamento de Proteína Pós-Traducional , Transdução de Sinais , Sirolimo/farmacologia
19.
World J Clin Cases ; 12(8): 1395-1405, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38576811

RESUMO

BACKGROUND: As a well-known fact to the public, gestational diabetes mellitus (GDM) could bring serious risks for both pregnant women and infants. During this important investigation into the linkage between GDM patients and their altered expression in the serum, proteomics techniques were deployed to detect the differentially expressed proteins (DEPs) of in the serum of GDM patients to further explore its pathogenesis, and find out possible biomarkers to forecast GDM occurrence. AIM: To investigation serum proteins differentially expressed in GDM were assessed using isobaric tag for relative and absolute quantitation (iTRAQ) proteomics and bioinformatics analyses. METHODS: Subjects were divided into GDM and normal control groups according to the IADPSG diagnostic criteria. Serum samples were randomly selected from four cases in each group at 24-28 wk of gestation, and the blood samples were identified by applying iTRAQ technology combined with liquid chromatography-tandem mass spectrometry. Key proteins and signaling pathways associated with GDM were identified by bioinformatics analysis, and the expression of key proteins in serum from 12 wk to 16 wk of gestation was further verified using enzyme-linked immunosorbent assay (ELISA). RESULTS: Forty-seven proteins were significantly differentially expressed by analyzing the serum samples between the GDM gravidas as well as the healthy ones. Among them, 31 proteins were found to be upregulated notably and the rest 16 proteins were downregulated remarkably. Bioinformatic data report revealed abnormal expression of proteins associated with lipid metabolism, coagulation cascade activation, complement system and inflammatory response in the GDM group. ELISA results showed that the contents of RBP4, as well as ANGPTL8, increased in the serum of GDM gravidas compared with the healthy ones, and this change was found to initiate from 12 wk to 16 wk of gestation. CONCLUSION: GDM symptoms may involve abnormalities in lipid metabolism, coagulation cascade activation, complement system and inflammatory response. RBP4 and ANGPTL8 are expected to be early predictors of GDM.

20.
RSC Adv ; 14(15): 10538-10545, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38567325

RESUMO

Graphene-based (Gr-based) electrothermal heaters, due to their light weight, low electrical resistance, high thermal conductivity, and easy accessibility, have attracted widespread attention in the field of electrothermal heating. To achieve a high steady-state temperature in electrothermal heaters under low voltage, here we constructed a Gr-based film with low electrical resistance. Firstly, we employed non-toxic vitamin C to reduce silver nitrate for the in situ chemical deposition of silver nanoparticles (AgNPs) on the Gr surface. The SEM results confirmed that the AgNPs were uniformly deposited on the Gr surface. The synergistic interaction between AgNPs and Gr provided high-speed electrons transport paths for the film. On the other hand, we employed biodegradable lignocellulose fiber (LCF) as a dispersant and film-forming agent. The aromatic ring structure of LCF interacts with Gr via π-π interactions, aiding the dispersion of Gr in aqueous solutions. SEM results revealed that LCF permeated through the surfaces and interstices of the two-dimensional Gr sheets, providing mechanical support for the composite film. This approach enables the creation of freestanding Gr-AgNPs/LCF electrothermal composites. The resistivity and electrothermal results demonstrated that the obtained 20 wt% Gr-based composite film possessed low electrical resistance (5.4 Ω sq-1) and exhibited an outstanding saturated temperature of 214 °C under a very low input voltage of 7 V. The preparation method of this Gr-based composite film is simple, easy to operate, and environmentally friendly, providing a new reference for the preparation of eco-friendly and high-performance resistance heating electronics.

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