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1.
Foods ; 13(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38540866

RESUMO

Pentacyclic triterpenes show potential as oleogelators, but their combination with various vegetable oils has limited research. This study selected linseed, rapeseed, sunflower, coconut, and palm oils to combine with the triterpenoid compound ß-amyrin for the preparation of oleogels. The stability, crystal network structure, and other properties of each oleogel were evaluated. The correlation between different oil types and the properties of corresponding oleogels was explored. The results showed that ß-amyrin formed stable oleogels with five vegetable oils under suitable temperature conditions, wherein especially the LO-based oleogel not only exhibited higher oil-binding capacity and hardness, but also demonstrated excellent stability at the microscopic level and notable rheological properties. Further analysis revealed a close correlation between the physicochemical properties of the oleogels and lipid characteristics, indicating that oleogels prepared from long-chain highly unsaturated fatty acids exhibit high stability. The above results indicate that ß-amyrin can be a novel candidate oleogelator and that the oil type can modify the properties of ß-amyrin-based oleogels. This study provides the latest reference for the application of pentacyclic triterpenoids in food.

2.
Molecules ; 28(14)2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37513410

RESUMO

Taking the extraction yield of Bletilla striata polysaccharide (BSP) as the index and taking the type of deep eutectic solvents (DESs), extraction time, extraction temperature, DES water content, and solid-liquid ratio as the investigation factors, single-factor and Box-Behnken response surface tests were carried out to optimize the extraction process of BSP. Thus, the antioxidant activity of BSP on DPPH radicals, ABTS radicals and ferric reducing antioxidant power were determined. The results showed that the most suitable deep eutectic solvent was DES-2, namely choline chloride-urea. The optimal extraction conditions for BSP were an extraction time of 47 min, extraction temperature of 78 °C, water content of 35%, and solid-liquid ratio of 1:25. Under this optimized condition, the extraction yield of BSP was able to reach (558.90 ± 8.83) mg/g, and recycling studies indicated the good cycle stability of the DES. Antioxidant results showed that BSP had superior antioxidant activity and had a dose-response relationship with drug concentration. Compared with Bletilla striata polysaccharide obtained via conventional hot water extraction (BSP-W), the extraction yield of BSP obtained through this method (BSP-2) increased by 36.77%, the scavenging activity of DPPH radicals increased by 24.99%, the scavenging activity of ABTS radicals increased by 41.16%, and the ferric reducing antioxidant power increased by 49.19%. Therefore, DESs as new green reagents and BSP extracted with DESs not only had a high yield but also had strong antioxidant activity.


Assuntos
Antioxidantes , Solventes Eutéticos Profundos , Antioxidantes/farmacologia , Antioxidantes/química , Solventes/química , Água/química , Polissacarídeos/farmacologia
3.
Curr Issues Mol Biol ; 45(7): 5403-5421, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37504259

RESUMO

This study investigated the pharmacological and pathological effects of aqueous mulberry leaf extract on type 1 diabetes mellitus mice induced with an intraperitoneal injection of streptozotocin (STZ). Diabetic mice were randomized into six groups: control (normal group), model, metformin-treated mice, and high-dose, medium-dose, and low-dose mulberry. The mulberry-treated mice were divided into high-, medium-, and low-dose groups based on the various doses of aqueous mulberry leaf extract during gavage. The efficacy of the six-week intervention was evaluated by measuring levels of fasting plasma glucose, alkaline phosphatase, alanine aminotransferase, aspartate transaminase, blood urea nitrogen, gamma-glutamyl transferase, glucose, high-density lipoprotein cholesterol, lactate dehydrogenase, and low-density lipoprotein cholesterol and recording body weight. Results revealed that mulberry leaf extract exhibited an ideal hypoglycemic effect, and the high-dose group was the most affected. Histology analysis, glycogen staining and apoptosis detection were used to study the extract's effects on the liver, kidney, and pancreatic cells of diabetic mice, enabling the assessment of its effectiveness and complications on a clinical and theoretical basis. It was shown that a certain concentration of aqueous mulberry leaf extract repaired the islet cells of type 1 diabetes mellitus mice, promoting normal insulin secretion. Herein, it was confirmed that mulberry leaf could be used to develop new hypoglycemic drugs or functional health food with broad applicability.

4.
Food Chem ; 423: 136220, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37156140

RESUMO

Ursolic acid (UA), a pentacyclic triterpenoid, has gained attentions due to its various health-promoting benefits, but exhibits poor bioavailability. This could be enhanced by changing the food matrix of UA in which it is present. In this study, several UA systems were constructed to investigate the bioaccessibility and bioavailability of UA in combination with in vitro simulated digestion and Caco-2 cell models. The results showed that the bioaccessibility of UA was significantly improved after adding rapeseed oil. Caco-2 cell models showed that the UA-oil blend was more advantageous than UA emulsion in total absorption. The results indicate that the location of UA distribution in oil determines the ease of UA release into the mixed micellar phase. This paper brings a new research idea and basis for the design of improving the bioavailability of hydrophobic compounds.


Assuntos
Digestão , Alimentos , Humanos , Disponibilidade Biológica , Células CACO-2 , Ácido Ursólico
5.
Foods ; 12(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36673401

RESUMO

Extracting ursolic acid (UA) from plant resources using organic solvents is incompatible with food applications. To address this, in this study, 15 edible hydrophobic deep eutectic solvents (HDESs) were prepared to extract UA from apple peel, the extraction conditions were optimized, and the optimization strategies were compared. It was found that the solubility of UA in the HDESs can be 9 times higher than the traditional solvent such as ethanol. The response surface optimization concluded that temperature had the greatest effect on the extraction and the optimized test conditions obtained as follows: temperature of 49 °C, time of 32 min, solid-liquid ratio of 1:16.5 g/mL, respectively. Comparing the response surface methodology (RSM) and artificial neural networks (ANN), it was concluded that ANN has more accurate prediction ability than RSM. Overall, the HDESs are more effective and environmentally friendly than conventional organic solvents to extract UA. The results of this study will facilitate the further exploration of HDES in various food and pharmaceutical applications.

6.
Foods ; 11(7)2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35407025

RESUMO

This work used the natural ingredient stigmasterol as an oleogelator to explore the effect of concentration on the properties of organogels. Organogels based on rapeseed oil were investigated using various techniques (oil binding capacity, rheology, polarized light microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy) to better understand their physical and microscopic properties. Results showed that stigmasterol was an efficient and thermoreversible oleogelator, capable of structuring rapeseed oil at a stigmasterol concentration as low as 2% with a gelation temperature of 5 °C. The oil binding capacity values of organogels increased to 99.74% as the concentration of stigmasterol was increased to 6%. The rheological properties revealed that organogels prepared with stigmasterol were a pseudoplastic fluid with non-covalent physical crosslinking, and the G' of the organogels did not change with the frequency of scanning increased, showing the characteristics of strong gel. The microscopic properties and Fourier transform infrared spectroscopy showed that stigmasterol formed rod-like crystals through the self-assembly of intermolecular hydrogen bonds, fixing rapeseed oil in its three-dimensional structure to form organogels. Therefore, stigmasterol can be considered as a good organogelator. It is expected to be widely used in food, medicine, and other biological-related fields.

7.
J Sci Food Agric ; 102(11): 4759-4769, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35218222

RESUMO

BACKGROUND: Phytosterols are considered to be one of the most promising gelators for obtaining oleogel because of their additional health benefits and natural coexist with vegetable oils. Previous studies have confirmed that individual phytosterols are not capable of structuring vegetable oils unless they act synergistically with other components. However, based on the self-assembly properties of stigmasterol (ST) in organic solvents, we speculate that it can also structure vegetable oils as a gelator alone. RESULTS: For the first time, the present study confirmed the feasibility of using ST alone as a gelator for structuring of vegetable oils, including rapeseed oil (RSO), olive oil (OLO) and flaxseed oil (FSO). RSO had the lowest ST gelation concentration (4%, w/w), and the oil-binding capacity and firmness value of the oleogels were the highest. The rheological results showed that all the samples were gelatinous (G' > G″). The results of differential scanning calorimeter and X-ray diffraction further confirmed that the properties of RSO-based oleogels are superior to those prepared by OLO and FSO. The microscopic results also confirmed that the crystal structure of RSO oleogels was more uniform, smaller and more densely distributed. CONCLUSION: The structural properties of the oleogels were positively correlated with the ST concentration, and various analysis indicators showed that the performance of the oleogel based on RSO was better than that of OLO and FSO. In summary, the present study used ST as a gelator to successfully prepare oleogels with excellent properties, which provides a feasible reference for researchers in related fields. © 2022 Society of Chemical Industry.


Assuntos
Fitosteróis , Estigmasterol , Compostos Orgânicos/química , Óleos de Plantas/química
8.
Food Res Int ; 147: 110573, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34399546

RESUMO

In this study, stable water-in-oil emulsions stabilized solely by a naturally occurring steroidal sapogenin was reported for the first time. The results show that a concentrated emulsion with an internal water ratio of up to 60% can be obtained with only 3% of diosgenin concentration. The concentration of diosgenin had a significant effect on the microstructure and rheological properties of the emulsions. More importantly, the emulsion has excellent freeze/thaw stability and thermal stability. The results of polarized light microscopy, CLSM, and XRD indicate that the great structural properties and high stability of the emulsion can be attributed to the combined action of the diosgenin crystal shells on the droplet surface and needle-crystals in the continuous phase. That is, Pickering stabilization and network stabilization acting synergistically on stabilization of the emulsions. This novel food grade water-in-oil emulsions demonstrated great potential for application in food and biomedical-related fields.


Assuntos
Diosgenina , Nanopartículas , Sapogeninas , Emulsões , Água
9.
J Pharm Pharmacol ; 73(1): 60-69, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33791810

RESUMO

OBJECTIVES: To explore the in vivo anti-obesity effect of chikusetsusaponin V and explore the underlying mechanism by transcriptomic and metabonomic methods. METHODS: The physiological parameters of high-fat-diet induced obese mice administered with or without 25 mg/kg and 100 mg/kg of chikusetsusaponin V by gavage for 16 weeks were recorded. In addition, the RNA-sequencing and UHPLC-Q-TOF techniques were applied to obtain the transcriptomic and metabolomic profiling, respectively. KEY FINDINGS: Chikusetsusaponin V could significantly alleviate the high-fat-diet induced increase in the weight of the whole body and obesity-related organs or tissues, and ameliorate the lipid content in the blood, the lipid accumulation in the livers, as well as the hypertrophy of the fat tissues. Importantly, transcriptomic results revealed that more than 30 genes involved in the pathway which closely associates with obesity, were significantly altered. Moreover, metabolomic data indicated the key differential metabolites enriched in the pathways such as the activated protein kinase signaling pathway which is a vital mediator of obesity and other processes. CONCLUSIONS: The integrative analysis highlighted that chikusetsusaponin V significantly influenced the activated protein kinase signaling pathway at both transcriptomic and metabolomic levels, thereby exerting anti-obesity effects.


Assuntos
Metaboloma , Obesidade/metabolismo , Panax/química , Fitoterapia , Extratos Vegetais/farmacologia , Saponinas/farmacologia , Transcriptoma , Tecido Adiposo/metabolismo , Animais , Peso Corporal , Dieta Hiperlipídica , Lipídeos/sangue , Fígado/metabolismo , Masculino , Metabolômica , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Obesidade/genética , Obesidade/prevenção & controle , Extratos Vegetais/uso terapêutico , Saponinas/uso terapêutico , Transdução de Sinais
10.
Chinese Journal of School Health ; (12): 198-202, 2021.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-873637

RESUMO

Objective@#To understand lunch satisfaction and leftovers of Changsha compulsory education schools under different supply modes served by school canteens and specialized enterprises,and to provide scientific basis for the government to formulate school lunch improvement policies.@*Methods@#Multistage stratified cluster sampling method was used to random select 2 203 students from 8 primary and secondary schools in Changsha who were administered with questionnair survey in April to May of 2018.@*Results@#For school lunch, the overall rate of satisfaction was 78.8%.The overall lunch satisfaction of female and primany school students were higher than that of male and junior high school students respectively,and the difference was statistically significant(P<0.05). Totally 76.0% of students had the highest satisfaction in food hygiene and the lowest satisfaction rate was 60.0% in food taste. By comparing different supply modes, the overall satisfaction rate of meal quantity was higher (47.8%) under school canteens, and that of dining environment was relatively high (43.7%) under specialized enterprises. "Don-t like some food" (63.8%) was the main reason for students leftovers under the two supply modes. The lunch leftover rate of specialized enterprises (37.8%) was significantly higher than that of school cafeteria (30.6%)(χ 2=12.81,P<0.05).@*Conclusion@#The satisfaction of food taste and the rate of lunch leftovers need to be further improved. School canteens environment and management should be strengthened, as well as the flexibility and communication under specialized enterprises and family-school communication. The joint efforts by school and family are needed for healthy eating education.

11.
Foods ; 9(3)2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32121041

RESUMO

Impacts of wheat flour substituted with various levels of Chinese yam (Dioscorea opposita Thunb.) flour (from 0% to 25%) on the dough rheological characteristics, gluten structure, baking performance, and antioxidant properties of bread were investigated. The water absorption increased significantly (p < 0.05), while development time and stability decreased remarkably (p < 0.05) as the proportion of yam flour increased. SEM results indicated that the addition of yam flour destroyed the gluten network structure in the dough. Fourier Transform Infrared Spectroscopy (FTIR) spectra showed that addition of yam flour decreased the content of α-helix and ß-sheet in gluten. With the increase in the proportion of yam flour, the specific volume and overall acceptability decreased (p < 0.05) whereas the total phenolics content (TPC), polysaccharides content, total flavonoids content (TFC), allantoin content, The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capability, fractal dimension, and hardness increased (p < 0.05). Overall, breads made of wheat flour replacement with no more than 15% Guihuai number 2 yam flour were of a high quality and had more antioxidant properties. These showed that Guihuai number 2 had broad application prospects in baked products.

12.
Toxicon ; 178: 82-91, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32135197

RESUMO

T-2 and HT-2 widely found in food products can seriously affect human and animal health. In this study, sterilized corn was inoculated with F. poae and incubated to allow fungal growth before being examined via liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) to determine the concentrations of T-2/HT-2. Broilers were then fed with a mix of moldy corn and normal feed at different ratios to obtain different toxin doses. After 35 days, the contaminated feed was replaced with mycotoxin-free feed and the distribution and concentration of residual toxins in the tissues and organs of the chickens were examined at different time points. The results showed that at the time of feed replacement (0 h), T-2 residue was present at significantly higher concentrations in the lungs and small intestines than in other tissues (P < 0.05). In addition, T-2 concentrations increased in a dose-dependent manner in the tissues of chickens in the low-, medium-, and high-dose groups; however, the differences in concentration between the groups were not statistically significant. The HT-2 content (0 h) in the livers and small intestines was significantly higher than that in other tissues (P < 0.05). At 48 h post-feed replacement, the concentration of T-2 dropped below detectable levels in all tissues while HT-2 could still be detected at 192 h post-feed replacement. Thus, this study reveals the distribution and persistence of residual T-2/HT-2 from moldy feed in broilers, providing a reference for the detection of these toxins in animal-derived food products and a theoretical basis for formulating food-safety and quality standards.


Assuntos
Ração Animal/análise , Contaminação de Alimentos/análise , Toxina T-2/análise , Animais , Galinhas , Fungos , Toxina T-2/análogos & derivados
13.
RSC Adv ; 10(47): 28376-28382, 2020 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35519143

RESUMO

As a possible alternative to hydrogels, eutectogels are formed by gelling natural deep eutectic solvents (NADESs) that may be closer to the intracellular environment than pure water. This study successfully prepared highly biodegradable and thermostable eutectogels based on polysaccharides and NADESs, and studied the possible mechanism of eutectogel formation. The results show that these eutectogels displayed excellent thermostability as both the G' and G'' values remained constant in the temperature range of 60-110 °C, and the weight of the eutectogels remained almost unchanged when held at 80 °C for 10 hours. Similar to the formation of xanthan gum-based hydrogels, water addition and annealing treatment are necessary for the preparation of xanthan gum-based eutectogels. XRD, DSC and FT-IR results show that the existence of xanthan gum affects the original hydrogen bonding network of the NADESs, which further indicate that the hydrogen bond interaction between xanthan gum and NADESs is an important cause of eutectogel formation and changes in gel properties. Rheological results show that the eutectogel is a weak gel with excellent thermostability and structure recovery. As it is more stable than hydrogels and greener than ion gels, the polysaccharide-based eutectogel is expected to be widely used in the fields of food, medicine and materials.

14.
Curr Med Chem ; 27(21): 3577-3597, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30767730

RESUMO

Obesity, associated with a series of complications such as diabetes, hypertension, and heart disease, is a great threat to human health and leads to increased morbidity and mortality. Despite the presence of anti-obesity agents on the market, the application of these drugs is limited because of their typical side effects. More effective and safe weight-loss drugs are being pursued by many researchers, correspondingly, growing small molecules and natural products with anti-obesity effects have been identified and the molecular mechanisms underlying the action of the novel and known compounds have at least partially been revealed. Therefore, the field does witness great progress year by year. In this review, we intend to provide a comprehensive and updated view on the known and novel compounds which possess anti-obesity effects and further classify them according to the molecular mechanisms of their actions in regulating the major anti-obesity pathways.


Assuntos
Obesidade , Fármacos Antiobesidade , Produtos Biológicos , Metabolismo Energético , Humanos
15.
BMC Vet Res ; 15(1): 248, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31307486

RESUMO

BACKGROUND: Porcine circovirus 2 (PCV2) is the causative agent of porcine circovirus-associated diseases (PCVADs). The infection of PCV2 is widespread and has serious consequence, thereby causing significant economic losses in the swine industry worldwide. Previously, we found that a strain named YiY-3-2-3 has a naturally occurring point mutation (G710 to A710) in ORF1 region, which leads to a shorten product of the rep gene (945 to 660 base pair). Importantly, the Rep protein is responsible for genome replication of PCV2. To explore the effects of this mutation on the PCV2 replication, in the current study we constructed infectious clone of this IF-YiY-3-2-3, as well as those of its two parental strains of IF-YiY-3-2-1 and IF-YiY-3-2-10. Subsequently, these infectious clones which have 1.1 copy of PCV2 genome of their corresponding strains were transfected into PK15 cells to obtain rescued viruses, respectively. RESULTS: Though all of the three infectious clones could be rescued, the copy number and infectivity of these rescued viruses were significantly different, as analyzed by fluorescence quantitative PCR, Tissue culture infectious dose 50 (TCID50), and indirect immunofluorescence assay (IFA). Notably, whether the PCV2 copy number, viral titer or the infectivity of rescued viruses from infectious clone IF-YiY-3-2-3 was significantly less than those of its parental clones. Meanwhile, the spatial structure of the Rep protein from the IF-YiY-3-2-3 displayed an apparent truncation at the C-terminal. CONCLUSIONS: These findings therefore suggest that the Rep protein with truncated C-terminal would reduce virus replication and infectivity, and there might also exist both favorable and unfavorable mutations in the ORF1 of PCV2 in the process of its evolution.


Assuntos
Infecções por Circoviridae/virologia , Circovirus/genética , Proteínas Virais/genética , Replicação Viral/genética , Sequência de Aminoácidos , Animais , Linhagem Celular , Circovirus/patogenicidade , DNA Viral , Mutação , Alinhamento de Sequência , Análise de Sequência de Proteína , Suínos
16.
Front Microbiol ; 10: 401, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30886609

RESUMO

Currently, the major measures of preventing and controlling microbial infection are vaccinations and drugs. However, the appearance of drug resistance microbial mounts is main obstacle in current anti-microbial therapy. One of the most ubiquitous actin-binding proteins, non-muscle myosin II (NM II) plays a crucial role in a wide range of cellular physiological activities in mammals, including cell adhesion, migration, and division. Nowadays, growing evidence indicates that aberrant expression or activity of NM II can be detected in many diseases caused by microbes, including viruses and bacteria. Furthermore, an important role for NM II in the infection of some microbes is verified. Importantly, modulating the expression of NM II with small hairpin RNA (shRNA) or the activity of it by inhibitors can affect microbial-triggered phenotypes. Therefore, NM II holds the promise to be a potential target for inhibiting the infection of microbes and even treating microbial-triggered discords. In spite of these, a comprehensive view on the functions of NM II in microbial infection and the regulators which have an impact on the roles of NM II in this context, is still lacking. In this review, we summarize our current knowledge on the roles of NM II in microbial-triggered discords and provide broad insights into its regulators. In addition, the existing challenge of investigating the multiple roles of NM II in microbial infection and developing NM II inhibitors for treating these microbial-triggered discords, are also discussed.

17.
Toxicol In Vitro ; 54: 137-146, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30261313

RESUMO

T-2 and HT-2 toxins can cause cytotoxicity and oxidative stress in animals, while DL-Selenomethionine plays an important role in preventing oxidative stress and improving cell viability. However, the role of DL-Selenomethionine in T-2/HT-2 toxins-induced cell damage is still unknown. In this study, we investigated whether DL-Selenomethionine plays a protective role against T-2/HT-2-induced cytotoxicity and oxidative stress in primary hepatocytes. Our results demonstrated that T-2/HT-2 toxins-exposed broiler hepatocytes exhibited significantly decreased cell viability and intracellular glutathione (GSH) concentration while increased Lacate dehydrogenase (LDH) leakage, intracellular reactive oxygen species (ROS), glutathione peroxidase (GSH-PX), malondialdehyde (MDA) and catalase (CAT) levels, as well as elevated expression levels of genes related to oxidative stress, in a toxin dose-dependent manner (P < 0.05). However, the application of DL-Selenomethionine into T-2/HT-2 treated hepatocytes effectively alleviated the adverse effects of T-2/HT-2, as demonstrated by increased cell viability, decreased LDH leakage, declined intracellular ROS and MDA levels, increased expression of oxidative stress-related genes, as well as accordingly enhanced activities of GSH, GSH-PX, SOD and CAT as compared to the control groups (P < 0.05). Therefore, our in vitro data demonstrate that DL-Selenomethionine can function as an effectively protective agent against T-2/HT-2-induced cytotoxicity and oxidative stress.


Assuntos
Antioxidantes/farmacologia , Hepatócitos/efeitos dos fármacos , Selenometionina/farmacologia , Toxina T-2/análogos & derivados , Animais , Sobrevivência Celular/efeitos dos fármacos , Galinhas , Hepatócitos/metabolismo , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Toxina T-2/toxicidade
18.
J Vis Exp ; (141)2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30531726

RESUMO

Relative to the issues of off-target effects and the difficulty of inserting a long DNA fragment in the application of designer nucleases for genome editing, embryonic stem (ES) cell-based gene-targeting technology does not have these shortcomings and is widely used to modify animal/mouse genome ranging from large deletions/insertions to single nucleotide substitutions. Notably, identifying the relatively few homologous recombination (HR) events necessary to obtain desired ES clones is a key step, which demands accurate and reliable methods. Southern blotting and/or conventional PCR are often utilized for this purpose. Here, we describe the detailed procedures of using those two methods to identify HR events that occurred in mouse ES cells in which the endogenous Myh9 gene is intended to be disrupted and replaced by cDNAs encoding other nonmuscle myosin heavy chain IIs (NMHC IIs). The whole procedure of Southern blotting includes the construction of targeting vector(s), electroporation, drug selection, the expansion and storage of ES cells/clones, the preparation, digestion, and blotting of genomic DNA (gDNA), the hybridization and washing of probe(s), and a final step of autoradiography on the X-ray films. PCR can be performed directly with prepared and diluted gDNA. To obtain ideal results, the probes and restriction enzyme (RE) cutting sites for Southern blotting and the primers for PCR should be carefully planned. Though the execution of Southern blotting is time-consuming and labor-intensive and PCR results have false positives, the correct identification by Southern blotting and the rapid screening by PCR allow the sole or combined application of these methods described in this paper to be widely used and consulted by most labs in the identification of genotypes of ES cells and genetically modified animals.


Assuntos
Southern Blotting/métodos , Marcação de Genes/métodos , Recombinação Homóloga/fisiologia , Células-Tronco Embrionárias Murinas/fisiologia , Reação em Cadeia da Polimerase/métodos , Animais , Sequência de Bases , Genótipo , Camundongos , Camundongos da Linhagem 129
19.
Mikrochim Acta ; 185(11): 522, 2018 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-30368605

RESUMO

A colorimetric assay is described for acrylamide (AA). It is based on color changes induced by an increase in the distance between gold nanoparticles (AuNPs) that is caused by AA copolymerization. First, AuNPs were modified with a thiolated propylene amide poly(ethylene glycol) that also contains the AA functionality. The carbon-carbon double bonds on the modified AuNPs can be polymerized under the catalysis of a photoinitiator and under UV irradiation. This results in the aggregation of the AuNPs and in a color change from red to gray. In the presence of AA, the distance between the AuNPs increases due to copolymerization with AA, and the solution of AuNPs preserves its original red color. Under optimized conditions, the absorption ratio (A525/A740) of the solution increases linearly in the 1 nM to 10 µM free AA concentration range, with a 0.2 nM limit of detection. Hence, the method meets the need for rapid monitoring of trace AA in food. The method has a relative error (RSD) that is lower compared to the accepted HPLC method. Graphical abstract Schematic of a novel colorimetric strategy for acrylamide (AA) detection based on the increase of distance between gold nanoparticles (AuNPs) caused by AA participated polymerization.

20.
Bioorg Chem ; 81: 203-210, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30144633

RESUMO

Although heparan sulfate (HS) is widely implicated in numerous physiological and pathological processes, the biological function of nucleus HS remains underexplored, largely due to its complex structure and high hydrophilic property. To supplement these efforts, ideal vehicles are drawing attention as they combine attractive features including lipid solubility for penetrating cell membrane, high affinity binding to its target receptor, metabolic stability, and no cellular actions resulting in toxicity. Herein, we develop a convenient and promising strategy to prepare HS-FK506 conjugates for membrane transport and entry into nucleus, where click chemistry takes easily place between the exocyclic allyl group of a clinic drug FK506 and thiol as a handle incorporated into HS analogues. HS derivatives for constructing the conjugates were synthesized using a cutting-edge chemoenzymatic method. Meantime, [35S] labeled 3'-phosphoadenosine 5'-phosphosulfate (PAP35S) and [14C] glucuronic acid (Glc A) were adopted to label HS-FK506 conjugates, respectively, to evaluate their efficiency of nucleus entry, as a result, 14C Glc A was sensitive, effective and reliable whereas PAP35S gave rise to a mixture of labeled compounds, hampering the understanding of structure-function relationship of nucleus HS. Compared with the corresponding HS, the amount of HS-FK506 conjugates to translocate into nucleus from radioactive assay experiments sharply increased, e.g. tridecasaccharide-FK506 1d increased by approximate 10 folds, offering a simple and robust platform for enabling hydrophilic compounds including carbohydrates to translocate into nucleus and shedding light on their biological functions.


Assuntos
Núcleo Celular/metabolismo , Heparitina Sulfato/análogos & derivados , Heparitina Sulfato/farmacocinética , Tacrolimo/análogos & derivados , Tacrolimo/farmacocinética , Sistemas de Liberação de Medicamentos , Desenho de Fármacos , Células HEK293 , Heparitina Sulfato/síntese química , Humanos , Tacrolimo/síntese química
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