Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 92
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Gels ; 10(6)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38920919

RESUMO

Gel treatment is an economical and efficient method of controlling excessive water production. The gelation of in situ gels is prone to being affected by the dilution of formation water, chromatographic during the transportation process, and thus controlling the gelation time and penetration depth is a challenging task. Therefore, a novel gel system termed preformed particle gels (PPGs) has been developed to overcome the drawbacks of in situ gels. PPGs are superabsorbent polymer gels which can swell but not dissolve in brines. Typically, PPGs are a granular gels formed based on the crosslinking of polyacrylamide, characterized by controllable particle size and strength. This work summarizes the application scenarios of PPGs and elucidates their plugging mechanisms. Additionally, several newly developed PPG systems such as high-temperature-resistant PPGs, re-crosslinkable PPGs, and delayed-swelling PPGs are also covered. This research indicates that PPGs can selectively block the formation of fractures or high-permeability channels. The performance of the novel modified PPGs was superior to in situ gels in harsh environments. Lastly, we outlined recommended improvements for the novel PPGs and suggested future research directions.

2.
Angew Chem Int Ed Engl ; : e202409507, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896433

RESUMO

Modulating the arrangement of superstructures through noncovalent interactions has a significant impact on macroscopic shape and the expression of unique properties. Constructing π-interaction-driven hierarchical three-dimensional (3D) superstructures poses challenges on account of limited directional control and weak intermolecular interactions. Here we report the construction of a 3D diamondoid superstructure, named π-Diamond, employing a ditopic strained Z-shaped building block comprising a porphyrin unit as bow-limb double-strapped with two m-xylylene units as bowstring. This superstructure, reminiscent of diamond's tetrahedral carbon composition, is composed of double-walled tetrahedron (DWT) driven solely by π-interactions. Hetero-π-stacking between porphyrin and m-xylylene panels drive the assembly of four building blocks predominantly into a DWT, which undergoes extension to create an adamantane unit and eventually a diamondoid superstructure wherein each porphyrin panel is shared by two neighboring tetrahedra through hetero-π-stacking. π-Diamond exhibits a solid-state fluorescent quantum yield 44 times higher than that of tetraphenylporphyrin along with excellent photocatalytic performance. The precise 3D directionality of π-interactions, achieved through strained multipanel building blocks, revolutionizes the assembly of hierarchical 3D superstructures driven by π-interactions.

3.
ACS Appl Mater Interfaces ; 16(5): 6356-6366, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38262045

RESUMO

Biodegradable electronic devices have gained significant traction in modern medical applications. These devices are generally desired to have a long enough working lifetime for stable operation and allow for active control over their degradation rates after usage. However, current biodegradable materials used as encapsulations or substrates for these devices are challenging to meet the two requirements due to the constraints of inadequate water resistance, poor mechanical properties, and passive degradation characteristics. Herein, we develop a novel biodegradable elastomer named POC-SS-Res by introducing disulfide linkage and resveratrol (Res) into poly(1,8-octanediol-co-citrate) (POC). Compared to POC, POC-SS-Res exhibits good water resistance and excellent mechanical properties in PBS, providing effective protection for devices. At the same time, POC-SS-Res offers the unique advantage of an active-controllable degradation rate, and its degradation products express low biotoxicity. Good biocompatibility of POC-SS-Res is also demonstrated. Bioelectronic components encapsulated with POC-SS-Res have an obvious prolongation of working lifetime in PBS compared to that encapsulated with POC, and its degradation rate can be actively controlled by the addition of glutathione (GSH).


Assuntos
Materiais Biocompatíveis , Polímeros , Polímeros/química , Materiais Biocompatíveis/química , Engenharia Tecidual , Elastômeros/química , Citratos/química
4.
Chem Rev ; 124(1): 27-123, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38156796

RESUMO

Ionic liquids (ILs) offer a wide range of promising applications due to their unique and designable properties compared to conventional solvents. Further development and application of ILs require correlating/predicting their pressure-viscosity-temperature behavior. In this review, we firstly introduce methods for calculation of thermodynamic inputs of viscosity models. Next, we introduce theories, theoretical and semi-empirical models coupling various theories with EoSs or activity coefficient models, and empirical and phenomenological models for viscosity of pure ILs and IL-related mixtures. Our modelling description is followed immediately by model application and performance. Then, we propose simple predictive equations for viscosity of IL-related mixtures and systematically compare performances of the above-mentioned theories and models. In concluding remarks, we recommend robust predictive models for viscosity at atmospheric pressure as well as proper and consistent theories and models for P-η-T behavior. The work that still remains to be done to obtain the desired theories and models for viscosity of ILs and IL-related mixtures is also presented. The present review is structured from pure ILs to IL-related mixtures and aims to summarize and quantitatively discuss the recent advances in theoretical and empirical modelling of viscosity of ILs and IL-related mixtures.

5.
Adv Skin Wound Care ; 37(1): 1-6, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38117173

RESUMO

OBJECTIVE: To establish a risk assessment model to predict postoperative National Pressure Injury Advisory Panel stage 2 or higher pressure injury (PI) risk in patients undergoing acute type A aortic dissection surgery. METHODS: This retrospective assessment included consecutive patients undergoing acute type A aortic dissection surgery in the authors' hospital from September 2017 to June 2021. The authors used LASSO (logistic least absolute shrinkage and selection operator) regression analysis to identify the most relevant variables associated with PI by running cyclic coordinate descent with 10-times cross-validation. The variables selected by LASSO regression analysis were subjected to multivariate logistic analysis. A calibration plot, receiver operating characteristic curve, and decision curve analysis were used to validate the model. RESULTS: There were 469 patients in the study, including 94 (27.5%) with postoperative PI. Ten variables were selected from LASSO regression: body mass index, diabetes, Marfan syndrome, stroke, preoperative skin moisture, hemoglobin, albumin, serum creatinine, platelet, and d-dimer. Four risk factors emerged after multivariate logistic regression: Marfan syndrome, preoperative skin moisture, albumin, and serum creatinine. The area under the receiver operating characteristic curve of the model was 0.765. The calibration plot and the decision curve analysis both suggested that the model was suitable for predicting postoperative PI. CONCLUSIONS: This study built an efficient predictive model that could help identify high-risk patients.


Assuntos
Dissecção Aórtica , Síndrome de Marfan , Úlcera por Pressão , Humanos , Creatinina , Úlcera por Pressão/diagnóstico , Úlcera por Pressão/etiologia , Estudos Retrospectivos , Dissecção Aórtica/cirurgia , Albuminas
6.
Angew Chem Int Ed Engl ; 62(46): e202314481, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37794215

RESUMO

Poly[n]catenanes have exceptional mechanical bonding properties that give them tremendous potential for use in the development of molecular machines and soft materials. Synthesizing these compounds has, however, proven to be a formidable challenge. Herein, we describe a concise method for the construction of twisted polycatenanes. Our approach involves using preorganized double helicates as templates, linked crosswise in a linear fashion by either silver ions or triple bonds. By using this approach, we successfully synthesized twisted polycatenanes with both coordination and covalent bonding employing Ag(I) ions and ethynylene units, respectively, as the linkages and leveraging the same Ag(I)-templated double helicate in both cases. Synthesis with Ag(I) ions formed a single-crystalline one-dimensional (1D) coordination poly[n]catenane, and synthesis using ethynylene units generated 1D fibers which self-assembled with solvents to form a gel. Our results confirm the potential of multi-stranded metallohelicates for creating sophisticated mechanically interlocked molecules and polymers, which could pave the way for exploration in the realms of molecular nanotopology and materials design.

7.
Biochem Genet ; 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37656330

RESUMO

A growing body of evidence suggests that miR-5189-3p plays a critical role in multiple diseases. This study aimed to investigate the function of miR-5189-3p in laryngeal squamous cell carcinoma (LSCC) and explore its underlying mechanisms. qRT-PCR was designed to determine the expression levels of miR-5189-3p and eukaryotic translation initiation factor 5A2 (EIF5A2), while CCK-8 assay was performed to measure the effects of miR-5189-3p on cell proliferation. Transwell assay was performed to evaluate cell invasion as well as migration, and wound healing assay was applied to demonstrate cell migratory ability. Target gene prediction and luciferase reporter assay were developed to screen the possible target gene of miR-5189-3p, and Western blot was designed to measure EIF5A2 protein expression. MiR-5189-3p was down-regulated in LSCC tissues and cell lines. Up-regulation of miR-5189-3p notably inhibited cell proliferation, invasion, and migration in HEP2 and FADU cells. EIF5A2 was the potential downstream gene of miR-5189-3p, and overexpression of miR-5189-3p apparently reduced EIF5A2 expression. Moreover, reintroduction of EIF5A2 rescued the tumor suppressive effects of miR-5189-3p. MiR-5189-3p functions as a tumor inhibitor in LSCC progression via directly regulating EIF5A2 and may be a potential therapeutic target for LSCC.

8.
Angew Chem Int Ed Engl ; 62(42): e202312238, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37656430

RESUMO

Delving into the influence of strain on organic reactions in small molecules at the molecular level can unveil valuable insight into developing innovative synthetic strategies and structuring molecules with superior properties. Herein, we present a molecular-strain engineering approach to facilitate the consecutive [1,2]-aryl shift (formal [1,3]-aryl shift) in molecular bows (MBs) that integrate 1,4-dimethoxy-2,5-cyclohexadiene moieties. By introducing ring strain into MBs through tethering the bow limb, we can harness the intrinsic mechanical forces to drive multistep aryl shifts from the para- to the meta- to the ortho-position. Through the use of precise intramolecular strain, the seemingly impractical [1,3]-aryl shift was realized, resulting in the formation of ortho-disubstituted products. The solvent and temperature play a crucial role in the occurrence of the [1,3]-aryl shift. The free energy calculations with inclusion of solvation support a feasible mechanism, which entails multistep carbocation rearrangements, for the formal [1,3]-aryl shift. By exploring the application of molecular strain in synthetic chemistry, this research offers a promising direction for developing new tools and strategies towards precision organic synthesis.

9.
Biomacromolecules ; 24(9): 4123-4137, 2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37584644

RESUMO

Citrate-based polymers are commonly used to create biodegradable implants. In an era of personalized medicine, it is highly desired that the degradation rates of citrate-based implants can be artificially regulated as required during clinical applications. Unfortunately, current citrate-based polymers only undergo passive degradation, which follows a specific degradation profile. This presents a considerable challenge for the use of citrate-based implants. To address this, a novel citrate-based polyester elastomer (POCSS) with artificially regulatable degradation rate is developed by incorporating disulfide bonds (S-S) into the backbone chains of the crosslinking network of poly(octamethylene citrate) (POC). This POCSS exhibits excellent and tunable mechanical properties, notable antibacterial properties, good biocompatibility, and low biotoxicity of its degradation products. The degradation rate of the POCSS can be regulated by breaking the S-S in its crosslinking network using glutathione (GSH). After a period of subcutaneous implantation of POCSS scaffolds in mice, the degradation rate eventually increased by 2.46 times through the subcutaneous administration of GSH. Notably, we observed no significant adverse effects on its surrounding tissues, the balance of the physiological environment, major organs, and the health status of the mice during degradation.


Assuntos
Elastômeros , Poliésteres , Camundongos , Animais , Elastômeros/química , Poliésteres/química , Ácido Cítrico , Alicerces Teciduais/química , Materiais Biocompatíveis/química , Engenharia Tecidual , Polímeros/química , Citratos/química
10.
Angew Chem Int Ed Engl ; 62(28): e202303035, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37167125

RESUMO

Macrocyclization of the bendable 2,7-dimethoxythianthrene with methylene linkages afforded a pair of homochiral macrocycles featuring a hex-nut-like geometry. Their structures were fully characterized by NMR spectroscopy, mass spectrometry, and single-crystal X-ray diffraction analysis. Their stable planar chirality facilitates efficient resolution of the pair of enantiomers which could be readily derivatized. Installing phenylethynyl groups on their rims leads to luminescent tubular macrocycles exhibiting circularly polarized luminescence with a large dissymmetry value |glum | of 5×10-3 . Supramolecular binding of electron-deficient guests by the tube results in fluorescence quenching, which proved its potential for the future development of switchable chiroptical systems.

11.
ACS Omega ; 8(13): 11941-11951, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37033857

RESUMO

Critical processing protocols of industrial bimetallic composite ionic liquid (IL) are necessary to assure good mass transfer rates for process optimization and efficient metal recovery. Here, the effects of different conditions on the electrochemical behavior and copper recovery from the industrial bimetallic composite IL are crucial for effective resource utilization. Cyclic voltammetry (CV) shows that the reduction of Cu(I) to Cu(0) during the cathodic reduction region is the irreversible diffusion-controlled process, and the diffusion coefficient increased with temperature which indicated that increasing temperature could promote the diffusion and mass transfer. During electrodeposition, metallic copper is obtained exclusively on the cathode, while CuCl2 accumulates exclusively on the anode. Scanning electron microscopy shows that the micron-size electrodeposits become larger and significantly rougher with increasing temperature and ultrasonic frequency, illustrating that these factors hasten the nucleation and crystallization rates at high overpotentials. The efficiency of copper recovery is greatly improved by employing high temperature and ultrasonic cavitation, and the highest values correspond to r = 76.9% at 80 °C and r = 63.6% at 40 kHz. The study lays the foundation for efficient and rapid recovery of copper from spent ILs.

12.
Angew Chem Int Ed Engl ; 62(25): e202218839, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-36897123

RESUMO

We report here the one-pot synthesis of benzo[1,2-a : 3,4-a' : 5,6-a'']triazulene (BTA), wherein three azulene units are embedded through a tandem reaction comprising two steps, Suzuki coupling and Knoevenagel condensation, between a readily available triborylated truxene precursor and 8-bromo-1-naphthaldehyde. Its nitration leads to a regioselective trinitrated product, namely, BTA-NO2 . Single-crystal X-ray crystallography revealed that the superstructure of BTA consists of a dimer stacked by two enantiomeric helicene conformers, while that of BTA-NO2 consists of an unprecedented π-tetramer stacked from two enantiomeric dimers, that is, four distinct helicene conformers. Both compounds show excellent stability and fluorescence with large Stokes shifts of up to 5100 cm-1 . In addition, BTA-NO2 exhibits a unique solvatochromic effect in different solvents and hydrogen-bonding-induced emission transfer in different ratios of THF/H2 O solutions.


Assuntos
Azulenos , Dióxido de Nitrogênio , Cristalografia por Raios X , Solventes/química
13.
J Sci Food Agric ; 103(3): 1561-1568, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36214060

RESUMO

BACKGROUND: Mulberry leaf extract (MLE) extracted from mulberry leaves is rich in a variety of bioactive ingredients and can be used as feed additives of weaned piglets. The present study was conducted to evaluate the effects of dietary MLE supplementation on intestinal barrier function, colon microbial numbers and microbial metabolites of weaned piglets. RESULTS: MLE supplementation increased the villus height and the villus height/crypt depth ratio in jejunum and ileum (P < 0.05), increased the mRNA expression of ZO-1, Claudin-1 and MUC-2 in the ileal mucosa (P < 0.05), and decreased the serum level of lipopolysaccharide (P < 0.01). Meanwhile, MLE reduced the mRNA expression of tumor necrosis factor-α and interleukin-1ß (P < 0.05) and increased secretory immunoglobulin A level in the ileal mucosa (P < 0.05). In addition, MLE increased the numbers of beneficial bacteria Bifidobacterium and Lactobacillus (P < 0.05) and decreased the number of potential pathogenic bacteria Escherichia coli (P < 0.05) in the colon. Correspondingly, MLE supplementation reduced the pH value of colonic digesta (P < 0.05) and altered the microbial fermentation pattern of the colon by increasing the concentrations of microbial metabolites derived from carbohydrates fermentation such as lactate, acetate, butyrate and total short-chain fatty acids (P < 0.05), and decreasing the concentrations of microbial metabolites derived from amino acid fermentation such as p-cresol, skatole, spermine, histamine and tryptamine (P < 0.05). CONCLUSION: MLE supplementation improved intestinal barrier function and displayed beneficial effects on colon microbes and microbial metabolism in weaned piglets. © 2022 Society of Chemical Industry.


Assuntos
Microbiota , Morus , Animais , Suínos , Suplementos Nutricionais/análise , Morus/metabolismo , Colo/metabolismo , Mucosa Intestinal/metabolismo , Escherichia coli , Extratos Vegetais/farmacologia , Extratos Vegetais/metabolismo , RNA Mensageiro/metabolismo , Desmame
14.
Front Vet Sci ; 9: 998956, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36304417

RESUMO

This study investigated the effects of guanidine acetic acid (GAA) supplementation on growth performance, carcass traits, and meat quality in Tibetan pigs. A total of 18 male Tibetan pigs (21.35 ± 0.99 kg) were randomly assigned to the control (basal diet) and GAA (basal diet + 800 mg/kg GAA) groups for 125 days. Growth performance, carcass traits, and meat quality in pigs, and the chemical composition of Longissimus thoracis (LT) were not altered by GAA. In LT, compared to the control group, dietary GAA increased the superoxide dismutase activity, transcripts of stearoyl CoA desaturase (SCD) and fatty acid synthase (FAS), and contents of glutamate, glutamine, C24:0, C20:3n-6, C20:4n-6, and polyunsaturated fatty acids (P < 0.05), but it decreased the malondialdehyde content (P < 0.001). In back fat, dietary GAA reduced the transcript of peroxisome proliferator-activated receptor γ (PPARγ) and the contents of C10:0, C12:0, C14:0, and C16:0 (P < 0.05), whereas it increased the contents of C22:0, C20:1, C22:1, C24:1, C20:2, C20:3n-3, and C22:2 (P < 0.05). These findings will provide a basis for high-quality Tibetan pork production.

15.
Biomacromolecules ; 23(10): 4268-4281, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36094894

RESUMO

As a biodegradable elastomer, poly(1,8-octanediol-co-citrate) (POC) has been widely applied in tissue engineering and implantable electronics. However, the unclear degradation mechanism has posed a great challenge for the better application and development of POC. To reveal the degradation mechanism, here, we present a systematic investigation into in vivo and in vitro degradation behaviors of POC. Initially, critical factors, including chemical structures, hydrophilic and water-absorbency characteristics, and degradation reaction of POC, are investigated. Then, various degradation-induced changes during in vitro degradation of POC-x (POC with different cross-linking densities) are monitored and discussed. The results show that (1) cross-linking densities exponentially drop with degradation time; (2) mass loss and PBS-absorption ratio grow nonlinearly; (3) the morphology on the cross-section changes from flat to rough at a microscopic level; (4) the cubic samples keep swelling until they collapse into fragments from a macro view; and (5) the mechanical properties experience a sharp drop at the beginning of degradation. Finally, the in vivo degradation behaviors of POC-x are investigated, and the results are similar to those in vitro. The comprehensive assessment suggests that the in vitro and in vivo degradation of POC occurs primarily through bulk erosion. Inflammation responses triggered by the degradation of POC-x are comparable to poly(lactic acid), or even less obvious. In addition, the mechanical evaluation of POC in the simulated application environment is first proposed and conducted in this work for a more appropriate application. The degradation mechanism of POC revealed will greatly promote the further development and application of POC-based materials in the biomedical field.


Assuntos
Ácido Cítrico , Elastômeros , Materiais Biocompatíveis/química , Citratos , Elastômeros/química , Teste de Materiais , Polímeros , Água
16.
J Anim Sci Biotechnol ; 13(1): 73, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35672805

RESUMO

BACKGROUND: Tauroursodeoxycholic acid (TUDCA), a hydrophilic bile acid, is the main medicinal component of bear bile and is commonly used to treat a variety of hepatobiliary diseases. Meanwhile, TUDCA has been shown to modulate the intestinal barrier function and alleviate DSS-induced colitis in mice. However, the effect of TUDCA on the intestinal barrier of weaned piglets remains largely unclear. METHODS: The weaned piglets and porcine IPEC-J2 intestinal epithelial cells were used to investigate the effects of TUDCA on intestinal barrier function in weaned piglets and explore the possible underlying mechanisms. In vivo, 72 healthy weaned piglets were randomly allocated into 2 groups according to their gender and body weight, and piglets were fed the basal diet with 0 (control, CON) and 200 mg/kg TUDCA for 30 d, respectively. Three female and three male piglets reflecting the average bodyweight were slaughtered in each group and samples were collected. In vitro, IPEC-J2 cells were subjected to 100 µmol/L TUDCA to explore the possible underlying mechanisms. RESULTS: Our results demonstrated that dietary TUDCA supplementation significantly reduced the diarrhea incidence of weaned piglets, possibly attributing to the TUDCA-enhanced intestinal barrier function and immunity. In addition, TUDCA supplementation altered serum metabolites and the relative abundance of certain gut bacteria, which might contribute to the improved intestinal barrier function. Furthermore, the in-vitro results showed that TUDCA improved the E. coli-induced epithelial barrier impairment of IPEC-J2 cells and increased Takeda G-coupled protein receptor 5 (TGR5) protein expression. However, knockdown of TGR5 and inhibition of myosin light chain kinase (MLCK) pathway abolished the TUDCA-improved epithelial barrier impairment in E. coli-treated IPEC-J2 cells, indicating the involvement of TGR5-MLCK in this process. CONCLUSIONS: These findings showed that TUDCA improved intestinal barrier function associated with TGR5-MLCK pathway and the alteration of serum metabolites and gut bacteria in weaned piglets, suggesting the potential application of TUDCA in improving gut health in piglet production.

17.
Angew Chem Int Ed Engl ; 61(33): e202205658, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35699676

RESUMO

A modular approach to azulene building blocks was developed starting from readily available aryl-substituted cyclopentadiene and ortho-haloaryl aldehyde by dehydration condensation followed by palladium-catalyzed C-H coupling. It facilitates the synthesis of four nonalternant isomers of pentacene and hexacene, namely, dibenzo[e,g]azulene, benzo[1,2-f : 5,4-f']diazulene, benzo[1,2-f : 4,5-f']diazulene, and naphtho[2,3-f : 6,7-f']diazulene, which exhibit narrow band gaps with high stability in addition to protonation-caused enhanced near-infrared fluorescence. We discovered that in these isomers, i) constitutional isomerism influences significantly their photoelectric properties and ii) the elongation of the conjugation system does not necessarily lead to a narrowing in the band gap. Due to the easy modifiability of the nonazulene building blocks, this strategy can be extended to modularly prepare numerous multiazulene-fused aromatics.

18.
Biology (Basel) ; 11(5)2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35625502

RESUMO

Aflatoxin B1 (AFB1) is one of the most toxic, naturally occurring carcinogen compounds and is produced by specific strains of fungi. Crop contamination with AFB1 can cause huge economic losses and serious health problems. Many studies have examined the microbiological degradation of AFB1, especially the use of efficient AFB1-degrading microorganisms, to control AFB1 contamination. Here, we reported the identification of a new Rhodococcus pyridinivorans strain (4-4) that can efficiently degrade AFB1 (degradation rate 84.9%). The extracellular component of this strain showed the strongest capacity to degrade AFB1 (degradation rate 83.7%). The effects of proteinase K, SDS, temperature, pH, incubation time, and AFB1 concentration on the AFB1 degradation ability of the extracellular component were investigated. We sequenced the complete genome of this strain, encoding 5246 protein-coding genes and 169 RNA genes on a circular chromosome and two plasmids. Comparative genomic analysis revealed high homology with other Rhodococcus strains with high AFB1-degradation ability. Further proteomic analyses of this strain identified a total of 723 proteins in the extracellular component, including multiple potential AFB1-degrading enzymes, along with enzymes that are reported to response to AFB1 treatment. Overall, the results demonstrate that R. pyridinivorans 4-4 would be an excellent candidate for the biodegradation and detoxification of AFB1 contamination.

19.
Molecules ; 27(8)2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35458611

RESUMO

The accumulation of reactive oxygen species (ROS) triggers oxidative stress in cells by oxidizing and modifying various cellular components, preventing them from performing their inherent functions, ultimately leading to apoptosis and autophagy. Glutathione (GSH) is a ubiquitous intracellular peptide with multiple functions. In this study, a hydrogen peroxide (H2O2)-induced oxidative damage model in IPEC-J2 cells was used to investigate the cellular protection mechanism of exogenous GSH against oxidative stress. The results showed that GSH supplement improved the cell viability reduced by H2O2-induced oxidative damage model in IPEC-J2 cells in a dose-dependent manner. Moreover, supplement with GSH also attenuated the H2O2-induced MMP loss, and effectively decreased the H2O2-induced mitochondrial dysfunction by increasing the content of mtDNA and upregulating the expression TFAM. Exogenous GSH treatment significantly decreased the ROS and MDA levels, improved SOD activity in H2O2-treated cells and reduced H2O2-induced early apoptosis in IPEC-J2 cells. This study showed that exogenous GSH can protect IPEC-J2 cells against apoptosis induced by oxidative stress through mitochondrial mechanisms.


Assuntos
Peróxido de Hidrogênio , Estresse Oxidativo , Apoptose , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/toxicidade , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo
20.
J Anim Physiol Anim Nutr (Berl) ; 106(4): 813-824, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34448260

RESUMO

This study investigated the effects of citrus extract on growth, carcass and meat quality of Duroc × Landrace × Large White pigs. One hundred and eight pigs (54 barrows, 54 females) were assigned to one of three dietary treatments for 138 days. The dietary treatments were (1) basic diet; (2) basic diet supplemented with 75 mg/kg chlortetracycline; and (3) basic diet supplemented with citrus extract (0.25 ml/kg during 56-112 days of age and 0.20 ml/kg during 113-194 days of age). No significant differences among treatments were found for growth performance, carcass characteristics, meat quality and free amino acids (p > 0.05). Feeding citrus extract tended to increase intramuscular fat (p = 0.052). Citrus extract and chlortetracycline increased C15:0 concentration (p = 0.016) and superoxide dismutase activity (p = 0.004). The pigs that received chlortetracycline exhibited the lowest (p = 0.033) muscle malondialdehyde concentration. Overall, citrus extract ameliorated some meat quality indicators without adverse effects on pig growth or carcass performance.


Assuntos
Clortetraciclina , Citrus , Ração Animal/análise , Animais , Composição Corporal , Clortetraciclina/farmacologia , Dieta/veterinária , Feminino , Carne/análise , Suínos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...