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Adjusting intracellular metabolic pathways and adopting suitable live state such as biofilms, are crucial for bacteria to survive environmental changes. Although substantial progress has been made in understanding how the histone-like nucleoid-structuring (H-NS) protein modulates the expression of the genes involved in biofilm formation, the precise modification that the H-NS protein undergoes to alter its DNA binding activity is still largely uncharacterized. This study revealed that acetylation of H-NS at Lys19 inhibits biofilm development in Shewanella oneidensis MR-1 by downregulating the expression of glutamine synthetase, a critical enzyme in glutamine synthesis. We further found that nitrogen starvation, a likely condition in biofilm development, induces deacetylation of H-NS and the trimerization of nitrogen assimilation regulator GlnB. The acetylated H-NS strain exhibits significantly lower cellular glutamine concentration, emphasizing the requirement of H-NS deacetylation in Shewanella biofilm development. Moreover, we discovered in vivo that the activation of glutamine biosynthesis pathway and the concurrent suppression of the arginine synthesis pathway during both pellicle and attached biofilms development, further suggesting the importance of fine tune nitrogen assimilation by H-NS acetylation in Shewanella. In summary, posttranslational modification of H-NS endows Shewanella with the ability to respond to environmental needs by adjusting the intracellular metabolism pathways.
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Histonas , Shewanella , Acetilação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes , Glutamina/genética , Histonas/metabolismo , Homeostase , Processamento de Proteína Pós-Traducional , Shewanella/genética , Shewanella/metabolismoRESUMO
Background: Episodic future thinking (EFT), which refers to people simulating possible future life events, has been suggested as a promising intervention for substance use disorders. Objectives: To examine the effect of gain-oriented and loss-oriented EFT on smoking cessation and its underlying mechanisms. Results: Two online experiments were conducted (Total N = 362). The results suggested that engaging in EFT led to increased short-term quitting behavior among smokers by bolstering their intentions to quit smoking (indirect effect = 0.10, bootstrap = 5000, bias-corrected 95% CI [0.0008, 0.2353]). Furthermore, the influence of EFT on quitting intention was mediated by anticipated regret (indirect effect = 0.37, bootstrap = 5000, bias-corrected 95% CI [0.2062, 0.5321]). There were no significant differences observed between the effects of gain-oriented and loss-oriented EFT on quitting intention (F = 0.28, p = .60). Importance: Our findings contribute to a growing body of literature on the adaptive functioning of EFT and lend support to the regret regulation theory. Health practitioners may consider integrating EFT into clinical interventions to help smokers quit smoking.
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Benign prostatic hyperplasia(BPH) is a common disease of the male urinary system, and its incidence rate in China is increasing. However, the mechanism underlying the pathogenesis of BPH remains unclear. Some studies demonstrated that the incidence of BPH was related to the change in the levels of steroid hormones. Too high content of dihydrotestosterone(DHT) in the body may cause BPH and other related diseases. Testosterone(T) is converted to DHT by 5α-reductase(SRD5A). By inhibiting the activity of this enzyme, the production of DHT can be reduced, and then the incidence of BPH can be lowered. Therefore, it has drawn great attention to screen and discover safer and more effective 5α-reductase inhibitors from natural medicines to treat prostatic hyperplasia without affecting the physiological function of men. This review summarizes the characteristics and tissue distribution of 5α-reductase, the discovery of 5α-reductase inhibitors in traditional Chinese medicine and natural medicines, 5α-reductase inhibitors commonly used in clinical practice and their side effects, as well as the animal models of prostatic hyperplasia and common detection indicators, aiming to provide a reference for more in-depth understanding and research about BPH and development of drugs.
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Inibidores de 5-alfa Redutase , Hiperplasia Prostática , Animais , Humanos , Masculino , Inibidores de 5-alfa Redutase/uso terapêutico , Colestenona 5 alfa-Redutase , Di-Hidrotestosterona , Hiperplasia Prostática/tratamento farmacológico , TestosteronaRESUMO
OBJECTIVE: To analyze the distribution of blaOXA among global Klebsiella pneumoniae and the characteristics of blaOXA-carrying K. pneumoniae. MATERIALS AND METHODS: The genomes of global K. pneumoniae were downloaded from NCBI by Aspera software. After quality check, the distribution of blaOXA among the qualified genomes was investigated by annotation with the resistant determinant database. The phylogenetic tree was constructed for the blaOXA variants based on the single nucleotide polymorphism (SNP) to explore the evolutionary relationship between these variants. The MLST (multi-locus sequence type) website and blastn tools were utilized to determine the sequence types (STs) of these blaOXA-carrying strains. and sample resource, isolation country, date and host were extracted by perl program for analyzing the characteristics of these strains. RESULTS: A total of 12,356 K. pneumoniae genomes were downloaded and 11,429 ones were qualified. Among them, 4386 strains were found to carry 5610 blaOXA variants which belonged to 27 varieties of blaOXAs, blaOXA-1 (n = 2891, 51.5%) and blaOXA-9 (n = 969, 17.3%) were the most prevalent blaOXA variants, followed by blaOXA-48 (n = 800, 14.3%) and blaOXA-232 (n = 480, 8.6%). The phylogenetic tree displayed 8 clades, three of them were composed of carbapenem-hydrolyzing oxacillinase (CHO). Totally, 300 distinct STs were identified among 4386 strains with ST11 (n = 477, 10.9%) being the most predominant one followed by ST258 (n = 410, 9.4%). Homo sapiens (2696/4386, 61.5%) was the main host for blaOXA-carrying K. pneumoniae isolates. The blaOXA-9-carrying K. pneumoniae strains were mostly found in the United States and blaOXA-48-carrying K. pneumoniae strains were mainly distributed in Europe and Asia. CONCLUSION: Among the global K. pneumoniae, numerous blaOXA variants were identified with blaOXA-1, blaOXA-9, blaOXA-48 and blaOXA-232 being the most prevalent ones, indicating that blaOXA rapidly evolved under the selective pressure of antimicrobial agents. ST11 and ST258 were the main clones for blaOXA-carrying K. pneumoniae.
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Carbapenêmicos , Klebsiella pneumoniae , Humanos , Estados Unidos , Tipagem de Sequências Multilocus , Filogenia , Europa (Continente)RESUMO
The objective of this study was to synthesize and characterize pharmaceutical characteristics of florfenicol sustained-release granules (FSRGs) in vitro and in vivo. FSRGs were synthesized using monostearate, polyethylene glycol 4000 and starch. In vitro dissolution profiles were studied using the rotating basket method in pH 1.2 HCl solution and pH 4.3 acetate buffer. Twenty-four male healthy Landrace×Yorkshire pigs were equally divided into three groups and administered a 20 mg/kg i.v bolus of florfenicol solution and dosed orally with FSRGs in the fasting and fed states. The Higuchi model was the best fit for the drug release profile in pH 1.2 and pH 4.3 media, and the mechanism of drug dissolution was governed by both diffusion and dissolution. We established a level A in vitro - in vivo correlation for FSRGs and the in vivo profile of the FSRGs can be estimated by the in vitro drug release.
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Projetos de Pesquisa , Tianfenicol , Masculino , Animais , Suínos , Correlação de Dados , Preparações de Ação RetardadaRESUMO
BACKGROUND: Pharmacotherapy constitutes the first-line treatment for depression. However, its clinical use is hindered by several limitations, such as time lag, side effects, and narrow therapeutic windows. Nanotechnology can be employed to shorten the onset time by ensuring permeation across the blood brain barrier (BBB) to precisely deliver more therapeutic agents; unfortunately, formidable challenges owing to the intrinsic shortcomings of commercial drugs remain. RESULTS: Based on the extraordinary capability of monoamines to regulate the neuronal environment, we engineer a network nanocapsule for delivering serotonin (5-hydroxytryptamine, 5-HT) and catalase (CAT) to the brain parenchyma for synergistic antidepression therapy. The nanoantidepressants are fabricated by the formation of 5-HT polymerization and simultaneous payload CAT, following by surface modifications using human serum albumin and rabies virus glycoprotein. The virus-inspired nanocapsules benefit from the surface-modifying strategies and exhibit pronounced BBB penetration. Once nanocapsules reach the brain parenchyma, the mildly acidic conditions trigger the release of 5-HT from the sacrificial nanocapsule. Releasing 5-HT further positively regulate moods, relieving depressive symptoms. Meanwhile, cargo CAT alleviates neuroinflammation and enhances therapeutic efficacy of 5-HT. CONCLUSION: Altogether, the results offer detailed information encouraging the rational designing of nanoantidepressants and highlighting the potential of nanotechnology in mental health disorder therapies.
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Nanocápsulas , Humanos , Serotonina , Barreira Hematoencefálica , Encéfalo , AminasRESUMO
Both antitumor and protumor property of mesenchymal stem cells (MSCs) have been demonstrated. We hypothesize that this contradiction is due to the heterogeneity of MSC subsets and that extracellular vesicles (EVs) from distinct MSC subsets can transfer the corresponding antitumor activities. Here we evaluated the antitumor activities of two subsets of adipose-derived mesenchymal stem cells (ADSCs) and ADSC-derived EVs (ADSC-EVs) in immunocompetent syngeneic mouse models of breast cancer. We identified CD90high and CD90low ADSC subsets and demonstrated that CD90high ADSCs could be converted into CD90low ADSCs by stimulation with LPS. CD90low ADSCs and its derived EVs significantly inhibited tumor growth in tumor-bearing mice. Benefit of tumor control were associated with decreased tumor cell proliferation and migration, and enhanced tumor cell apoptosis mediated by ADSC-EVs. Antioncogenic miRNA-16-5p loaded CD90low ADSC-EVs further significantly enhanced antitumor activities. Taken together, this study represents the first attempt to apply our newly identified antitumor ADSCs and its derived EVs in preclinical treatment of breast cancer. This study also provides the evidence that EVs can serve as a novel and effective therapeutics or drug delivery vesicle. This new therapeutic approach could be potentially applicable to breast cancer and many other types of cancer.
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Neoplasias da Mama/terapia , Vesículas Extracelulares/transplante , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Tecido Adiposo/citologia , Animais , Apoptose , Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Vesículas Extracelulares/imunologia , Vesículas Extracelulares/metabolismo , Feminino , Células-Tronco Mesenquimais/imunologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Invasividade Neoplásica , Fenótipo , Antígenos Thy-1/metabolismo , Carga TumoralRESUMO
Qu-feng-sheng-shi Granules (QFSSG), a common prescription for the treatment of chronic inflammation and allergic rhinitis, is widely used in the clinic as a traditional Chinese medicine. Chemical analysis and quality control studies of this formulation are relatively limited compared with pharmacological studies. In this study, a high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (HPLC-ESI-Q/TOF-MSn ) was used to identify the components in this prescription. Next, to quantify six major compounds, an HPLC-UV method was developed and validated. The results showed that 53 compounds were identified based on the MSn data, retention time and previous reports, including 17 coumarins, 14 lignans, 10 chromones, nine phenylethanoid glycosides and three other compounds, were identified or tentatively assigned. Contents of six major bioactive compounds (4'-O-ß-glucopyranosyl-5-O-methylvisamminol, Prim-O-glucosylcimifugin, forsythin, magnolin, imperatorin, isoimperatorin) could be determined by HPLC simultaneously. In addition, the potential anti-inflammatory activity of six major compounds was determined too, and we found that four compounds (4'-O-ß-glucopyranosyl-5-O-methylvisamminol, Prim-O-glucosylcimifugin, forsythin, imperatorin) have a potent nitric oxide inhibitory effect. In conclusion, this work provided comprehensive information on the quality control of QFSSG and evaluated the potential biological activity of the main components in QFSSG, which can contribute to understanding and using it more scientifically.
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Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Sobrevivência Celular/efeitos dos fármacos , Cromonas/análise , Cromonas/química , Cumarínicos/análise , Cumarínicos/química , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Glicosídeos/análise , Glicosídeos/química , Lignanas/análise , Lignanas/química , Limite de Detecção , Modelos Lineares , Camundongos , Células RAW 264.7 , Reprodutibilidade dos Testes , Espectrofotometria UltravioletaRESUMO
In solution, nanoparticles may be conceptually compartmentalized into cores and engineered surface coatings. Recent advances allow for simple and accurate characterization of nanoparticle cores and surface shells. After introduction into a complex biological environment, adsorption of biological molecules to the nanoparticle surface as well as a loss of original surface components occur. Thus, colloidal nanoparticles in the context of the biological environment are hybrid materials with complex structure, which may result in different chemical, physical, and biological outcomes as compared to the original engineered nanoparticles. In this review, we will discuss building up an engineered inorganic nanoparticle from its inside core to its outside surface and following its degradation in a biological environment from its outside to its inside. This will involve the way to synthesize selected inorganic nanoparticles. Then, we will discuss the environmental changes upon exposure of these nanoparticles to biological media and their uptake by cells. Next, the intracellular fate of nanoparticles and their degradation will be discussed. Based on these examples, the need to see nanoparticles in the context of the biological environment as dynamic hybrid materials will be highlighted.
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Biopolímeros/química , Coloides/química , Meio Ambiente , Compostos Inorgânicos/química , Nanopartículas/química , HumanosRESUMO
In this study, uniform superparamagnetic Fe3O4/carboxymethyl chitosan composite nanospheres with high saturation magnetization were successfully synthesized via a modified inverse emulsion crosslinking approach, using genipin as a cross-linking agent. These nanospheres were then characterized, and their protein adsorption capacity was further investigated under various conditions. The implementation of a sonication treatment of a mixture containing Fe3O4 nanoparticles and carboxymethyl chitosan before the emulsion process significantly promoted the homogeneity of Fe3O4 nanoparticles in an aqueous phase system. The Fe3O4/carboxymethyl chitosan composite nanospheres were of uniform spherical structure, were approximately 230 nm in size, and possessed superparamagnetic characteristics with a mean saturation magnetization as high as 35 emu g(-1), corresponding to a magnetite content of 43%. Lysozyme was then employed as a model protein to investigate the effects of pH, incubation time and ion strength on the protein adsorption capacity of the as-synthesized composite nanospheres. The as-obtained composite nanospheres could serve as a promising candidate for fast and efficient protein adsorption.
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Quitosana/análogos & derivados , Óxido Ferroso-Férrico/química , Muramidase/química , Nanosferas , Adsorção , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios XRESUMO
This study aimed to develop an ammonia and pH super-sensitive label by incorporating methyl red and bromothymol blue (MR-BTB, MB) into gellan gum/sodium carboxymethyl cellulose (GG/CMC-Na, GC). Furthermore, E-nose as an auxiliary tool combined with the labels to monitor meat freshness. Results showed that MB had more color change than pure MR or BTB, and the detection limit of ammonia about the MR-BTB (1:2) group was only 2.82 ppm. The addition of MB significantly increased tensile strength, moisture content, and water solubility, but decreased elongation at break and transmittance of the GC label (p < 0.05). The result of FTIR and SEM indicated the formation of hydrogen bonds and well compatibility between MB and GC. Furthermore, the color of the GC-10.0MB label was constantly obviously changing during meat storage, indicating that the GC-10.0MB label had great potential for monitoring the freshness of the lamb meat. A high correlation was found between ΔE of GC-10.0MB label and TVB-N (R2 = 0.9092) and pH (R2 = 0.9114) of meat. Interestingly, the high correlation between ΔE of GC-10.0 MB label and the response value of S2 (R2 = 0.7531), S6 (R2 = 0.9921), and S7 sensor (R2 = 0.8325) of E-nose was also found.
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Amônia , Carboximetilcelulose Sódica , Colorimetria , Polissacarídeos Bacterianos , Carboximetilcelulose Sódica/química , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/análise , Concentração de Íons de Hidrogênio , Amônia/análise , Amônia/química , Animais , Colorimetria/métodos , Ovinos , Corantes/química , Corantes/análise , Carne Vermelha/análise , Carne/análise , CorRESUMO
In this research, different seeds of Australian-grown date palm (Phoenix dactylifera L.) were studied to evaluate the antioxidant potential and analyze their phenolic constituents. Phenolic compounds were extracted from seeds of various Australian-grown date varieties at different ripening stages. Eight varieties of date seeds (Zahidi, Medjool, Deglet nour, Thoory, Halawi, Barhee, Khadrawy, and Bau Strami) at three ripening stages (Kimri, Khalal, and Tamar) were investigated in this study. Date seeds at Khalal (9.87-16.93 mg GAE/g) and Tamar (9.20-27.87 mg GAE/g) stages showed higher total phenolic content than those at Kimri stage (1.81-5.99 mg GAE/g). For antioxidant assays like DPPH, FRAP, ABTS, RAP, FICA, and TAC, date seeds at Khalal and Tamar stages also showed higher antioxidant potential than Kimri stage. However, date seeds at Kimri stage (55.24-63.26 mg TE/g) expressed higher radical scavenging activity than Khalal (13.58-51.88 mg TE/g) and Tamar (11.06-50.92 mg TE/g) stages. Phenolic compounds were characterized using LC-ESI-QTOF-MS/MS, revealing the presence of 37 different phenolic compounds, including 8 phenolic acids, 18 flavonoids, and 11 other phenolic compounds. Further, phenolic compounds were quantified using LC-DAD, revealing that Zahidi variety of date seeds exhibited the highest content during the Kimri stage. In contrast, during the Khalal and Tamar stages, Deglet nour and Medjool date seeds displayed higher concentrations of phenolic compounds. The results indicated an increase in phenolic content in date seeds after the Kimri stage, with significant variations observed among different date varieties.
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Antioxidantes , Phoeniceae , Austrália , Espectrometria de Massas em Tandem , Fenóis , SementesRESUMO
The coral reef microbiome plays a vital role in the health and resilience of reefs. Previous studies have examined phage therapy for coral pathogens and for modifying the coral reef microbiome, but defence systems against coral-associated bacteria have received limited attention. Phage defence systems play a crucial role in helping bacteria fight phage infections. In this study, we characterized a new defence system, Hma (HmaA-HmaB-HmaC), in the coral-associated Halomonas meridiana derived from the scleractinian coral Galaxea fascicularis. The Swi2/Snf2 helicase HmaA with a C-terminal nuclease domain exhibits antiviral activity against Escherichia phage T4. Mutation analysis revealed the nickase activity of the nuclease domain (belonging to PDD/EXK superfamily) of HmaA is essential in phage defence. Additionally, HmaA homologues are present in ~1000 bacterial and archaeal genomes. The high frequency of HmaA helicase in Halomonas strains indicates the widespread presence of these phage defence systems, while the insertion of defence genes in the hma region confirms the existence of a defence gene insertion hotspot. These findings offer insights into the diversity of phage defence systems in coral-associated bacteria and these diverse defence systems can be further applied into designing probiotics with high-phage resistance.
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Antozoários , DNA Helicases , Halomonas , Halomonas/genética , Halomonas/enzimologia , Animais , Antozoários/microbiologia , Antozoários/virologia , DNA Helicases/genética , DNA Helicases/metabolismo , Bacteriófagos/genética , Bacteriófagos/enzimologia , Bacteriófagos/fisiologia , Desoxirribonucleases/genética , Desoxirribonucleases/metabolismoRESUMO
Temperate phages can interact with bacterial hosts through lytic and lysogenic cycles via different mechanisms. Lysogeny has been identified as the major form of bacteria-phage interaction in the coral-associated microbiome. However, the lysogenic-to-lytic switch of temperate phages in ecologically important coral-associated bacteria and its ecological impact have not been extensively investigated. By studying the prophages in coral-associated Halomonas meridiana, we found that two prophages, Phm1 and Phm3, are inducible by the DNA-damaging agent mitomycin C and that Phm3 is spontaneously activated under normal cultivation conditions. Furthermore, Phm3 undergoes an atypical lytic pathway that can amplify and package adjacent host DNA, potentially resulting in lateral transduction. The induction of Phm3 triggered a process of cell lysis accompanied by the formation of outer membrane vesicles (OMVs) and Phm3 attached to OMVs. This unique cell-lysis process was controlled by a four-gene lytic module within Phm3. Further analysis of the Tara Ocean dataset revealed that Phm3 represents a new group of temperate phages that are widely distributed and transcriptionally active in the ocean. Therefore, the combination of lateral transduction mediated by temperate phages and OMV transmission offers a versatile strategy for host-phage coevolution in marine ecosystems.
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Antozoários , Halomonas , Prófagos , Halomonas/virologia , Halomonas/genética , Antozoários/microbiologia , Antozoários/virologia , Prófagos/genética , Prófagos/fisiologia , Animais , Lisogenia , Transdução Genética , Mitomicina/farmacologiaRESUMO
This communication explores the intricate relationship between food waste and climate change, considering aspects such as impacts, projections, and emissions. It focuses on the pressing issue of waste generation and its potential consequences if current trends persist, and emphasises the importance of efficient solid waste management in improving environmental quality and fostering economic development. It also highlights the challenges faced by developing countries in waste collection and disposal, drawing comparisons with the waste utilisation methods used by developed nations. The review delves into the link between food waste and climate change, noting the paradoxical situation of food wastage against the backdrop of global hunger and malnutrition. It underscores the scientific evidence connecting food waste to climate change and its implications for food security and climate systems. Additionally, it examines the environmental burden imposed by food waste, including its contribution to greenhouse gas emissions and the depletion of resources such as energy, water, and land. Besides environmental concerns, this communication also highlights the ethical and socioeconomic dimensions of food waste, discussing its influence on Sustainable Development Goals, poverty, and social inequality. The communication concludes by advocating for collective action and the development of successful mitigation strategies, technological solutions, and policy interventions to address food waste and its climate impacts. It emphasises the need for collaboration, awareness, and informed decision-making to ensure a more sustainable and equitable future.
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Mudança Climática , Eliminação de Resíduos , Alimentos , Perda e Desperdício de Alimentos , Junções ComunicantesRESUMO
This study investigated the effect of different hydrocolloids on the improvement of the printability and post-processing stability of minced chicken meat, each hydrocolloid was prepared with 1 % formulation and compared with the control. The effects of these hydrocolloids on the rheological properties of chicken mince and complex model printing capability were explored separately, while the cooking loss and microstructure changes of the samples before and after heating were analyzed. The results showed that the chicken mince gel containing carrageenan was more suitable for printing, increased the yield stress and apparent viscosity of the samples, and the printing process was easier to mold. In addition, carrageenan increased the hardness of the samples, and the microstructures were compact and changed little during the heating process, and the water was locked in the gel matrix, reducing shape changes during the heating process. The use of hydrocolloids improves the stability of post-processing of chicken 3D printing.
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Galinhas , Coloides , Impressão Tridimensional , Reologia , Animais , Coloides/química , Viscosidade , Carragenina/química , Culinária , Temperatura Alta , Temperatura , Produtos da Carne/análiseRESUMO
High and rising rates of smoking and drinking among Chinese adolescents are contributing to increasingly serious physical and mental health issues. While impulsivity has been demonstrated to be significantly related to adolescent cigarette and alcohol use, little is known about the mechanisms behind this association. The current study focused on resilience and depressive symptoms as potential mediators of this link, exploring the indirect pathways connecting impulsivity to teenage tobacco and alcohol use. Possible gender differences in this indirect pathway were also explored. Participants were secondary school students from southern China (N = 3466; 49.2% were female; Mage = 14.18; SDage = 1.57). Results revealed that adolescents who were more impulsive used cigarettes and alcohol more frequently, and that this effect was partially mediated by lower resilience and more depressive symptoms. It is noteworthy that there were gender differences in this mediating effect, with the effect of impulsivity on cigarette use for girls being mediated by resilience and depressive symptoms, whereas this statistically significant association was not identified for boys. These findings show how adolescents' impulsivity drives them to smoke and drink, and also emphasize gender as a crucial consideration for intervening with adolescents' drinking and smoking behaviors.
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The uptake and the fate of Zr-based metal-organic-framework nanoparticles labeled with organic fluorophores in HeLa cells has been monitored with fluorescence detection and elemental analysis. The nanoparticles have been selected as a model system of carrier nanoparticles (here Zr-based metal-organic-framework nanoparticles) with integrated cargo molecules (here organic fluorophores), with aze that does not allow for efficient exocytosis, a material which only partly degrades under acidic conditions as present in endosomes/lysosomes, and with limited colloidal stability. Data show that, for Zr-based metal-organic-framework nanoparticles of 40 nm size as investigated here, the number of nanoparticles per cells decreases faster due to particle redistribution upon proliferation than due to nanoparticle exocytosis and that, thus, also for this system, exocytosis is not an efficient pathway for clearance of the nanoparticles from the cells.
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Tomatoes (Solanum lycopersicum) are highly involved in diets consumed worldwide, and are rich in bioactive compounds including phenolics, carotenoids and vitamins. In this study, four different varieties of fresh tomato pulp (Oxheart, Green Zebra, Kumato and Roma) were used to estimate the bioaccessibility of target phenolic compounds during in vitro gastrointestinal digestion and colonic fermentation, and to determine their antioxidant capacity. The production of short chain fatty acids (SCFAs) was also estimated during colonic fermentation. Among these, Roma displayed relatively higher total phenolic content (TPC) and free radical scavenging (2,2'-diphenyl-1-picrylhydrazyl (DPPH) assay) values after gastrointestinal digestion of 0.31 mg gallic acid equivalents (GAE) per g and 0.12 mg Trolox equivalents (TE) per g. Kumato exhibited the highest total flavonoid content (TFC) of 2.47 mg quercetin equivalents (QE) per g after 8 hours of colonic fermentation. Oxheart and Roma showed similar ferric reducing antioxidant power (FRAP) values of around 4.30 mg QE per g after 4 hours of faecal reaction. Catechin was the most bioaccessible phenolic compound in all fresh tomatoes, and could be completely decomposed after intestinal digestion, whereas the release of some bonded phenolic compounds required the action of gut microflora. Kumato and Green Zebra showed higher production of individual and total SCFAs for 16 hours of fermentation, which would provide more gut health benefits.
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Solanum lycopersicum , Antioxidantes , Digestão , Ácidos Graxos Voláteis , Fermentação , Fenóis , QuercetinaRESUMO
Phenolic compounds present in coffee beans could generate flavor and bring benefits to health. This study aimed to evaluate the impacts of commercial roasting levels (light, medium, and dark) on phenolic content and antioxidant potential of Arabica coffee beans (Coffea arabica) comprehensively via antioxidant assays. The phenolic compounds in roasted samples were characterized via liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS/MS). Furthermore, the coffee volatile compounds were identified and semi-quantified by headspace/gas chromatography-mass spectrometry (HS-SPME-GC-MS). Generally, for phenolic and antioxidant potential estimation, light roasted samples exhibited the highest TPC (free: 23.97 ± 0.60 mg GAE/g; bound: 19.32 ± 1.29 mg GAE/g), DPPH, and FRAP. The medium roasted beans performed the second high in all assays but the highest ABTS+ radicals scavenging capacity (free: 102.37 ± 8.10 mg TE/g; bound: 69.51 ± 4.20 mg TE/g). Totally, 23 phenolic compounds were tentatively characterized through LC-ESI-QTOF-MS/MS, which is mainly adopted by 15 phenolic acid and 5 other polyphenols. The majority of phenolic compounds were detected in the medium roasted samples, followed by the light. Regarding GC-MS, a total of 20 volatile compounds were identified and semi-quantified which exhibited the highest in the dark followed by the medium. Overall, this study confirmed that phenolic compounds in coffee beans would be reduced with intensive roasting, whereas their antioxidant capacity could be maintained or improved. Commercial medium roasted coffee beans exhibit relatively better nutritional value and organoleptic properties. Our results could narrow down previous conflicts and be practical evidence for coffee manufacturing in food industries.