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1.
J Agric Food Chem ; 69(35): 10272-10280, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34436886

RESUMO

Salt is very important for human health and food seasoning. Recently, several peptides isolated from natural food products have been reported exhibiting a salty taste or a saltiness-enhancing function. In this investigation, taste-active peptides occurring in commercial Chinese fermented soybean curd were isolated and identified using ultrafiltration, gel permeation chromatography, ion-exchange chromatography, and nano-LC/Q-TOF MS/MS. The salty taste-enhancing function of the target fractions was confirmed by both a rat taste cell model and/or human sensory evaluation. Four decapeptides were found as taste-active compounds. Among them, peptide E (EDEGEQPRPF) was the most potent saltiness-enhancing peptide: 0.4 mg/mL in 50 mmol/L NaCl solution could increase its salty perception equivalent to the salt level of 63 mmol/L NaCl reference solution. The sequence of the peptide has been found in the α'-subunit of ß-conglycinin [Glycine max]. The remaining peptides V (VGPDDDEKSW), DD (DEDEQPRPIP), and DG (DEGEQPRPFP) showed umami and kokumi tastes as well as a weak saltiness-enhancing sensation. These findings suggest that the decapeptide EDEGEQPRPF could be a possible alternative to partially reduce the amount of sodium intake without compromising for saltiness.


Assuntos
Cloreto de Sódio , Alimentos de Soja , Animais , China , Peptídeos , Ratos , Alimentos de Soja/análise , Espectrometria de Massas em Tandem , Paladar
2.
J Affect Disord ; 281: 271-278, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33341009

RESUMO

BACKGROUND: Neglect and physical abuse may be typical risk factors for aggressive behavior in adolescents. However, findings on their specific effects and sex differences are still unclear. This study aimed to examine the specific effects of neglect and physical abuse on adolescent aggressive behaviors and to further explore the potential sex-specific effect. METHODS: A multicenter school-based survey was conducted in rural China. A total of 15,957 students aged 11-20 years completed self-report questionnaires to record aggressive behaviors, neglect and physical abuse, and other related information. Participants were grouped into those who experienced none, one of, or both neglect and physical abuse for statistical analyses. RESULTS: Of the participants, 37.0% experienced both neglect and physical abuse, 30.0% experienced neglect only, and 9.8% experienced physical abuse only. Higher risk for physical aggression (OR=1.24, 95% CI=1.06-1.45), and lower risk for verbal aggression (OR=0.83, 95% CI=0.72-0.94) and hostility (OR=0.81, 95% CI=0.69-0.94) were found in the physical abuse only group as compared to the neglect only group. No sex difference was found between neglect or physical abuse and general aggressive behaviors (P>0.05), except that females were more likely to exert physical aggression than males when exposed to neglect and physical abuse (P<0.05). LIMITATIONS: Cross-sectional design, retrospective self-report data, and not including other maltreatment subtypes. CONCLUSIONS: Neglect and physical abuse may each have distinct sensitivity for different subtypes of aggression. Targeted treatment for diverse aggressive symptoms is suggested, and strategies to prevent both neglect and physical abuse across gender would yield comprehensive benefits.


Assuntos
Maus-Tratos Infantis , Abuso Físico , Adolescente , Adulto , Agressão , Criança , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Estudos Retrospectivos , Inquéritos e Questionários , Adulto Jovem
3.
Science ; 370(6513): 247-250, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-33033222

RESUMO

Neural networks display the ability to transform forward-ordered activity patterns into reverse-ordered, retrospective sequences. The mechanisms underlying this transformation remain unknown. We discovered that, during active navigation, rat hippocampal CA1 place cell ensembles are inherently organized to produce independent forward- and reverse-ordered sequences within individual theta oscillations. This finding may provide a circuit-level basis for retrospective evaluation and storage during ongoing behavior. Theta phase procession arose in a minority of place cells, many of which displayed two preferred firing phases in theta oscillations and preferentially participated in reverse replay during subsequent rest. These findings reveal an unexpected aspect of theta-based hippocampal encoding and provide a biological mechanism to support the expression of reverse-ordered sequences.


Assuntos
Adaptação Psicológica/fisiologia , Região CA1 Hipocampal/fisiologia , Ritmo Teta , Animais , Masculino , Ratos , Ratos Endogâmicos LEC
4.
Front Plant Sci ; 11: 133, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32158456

RESUMO

The micro-morphology of leaf epidermises is valuable for the study of leaf development and function, as well as the classification of plant species. There have been few studies comparing different preparation and imaging methods for visualizing the leaf epidermis. Here, four specimen preparation methods were used to investigate the leaf epidermis morphology of Arabidopsis, radish, cucumber, wheat, rice, and maize, under an inverted basic light microscope (LM), a laser scanning confocal microscope (LSCM), or a scanning electron microscope (SEM). Optical microscope specimens were obtained using either the direct isolation method or the chloral hydrate-based clearing method. SEM images were obtained using a standard stage for conventional dehydrated samples or a Coolstage for fresh tissue. Different parts of epidermis peels were well focused under the LM. Investigation of samples cleared by chloral hydrate is convenient and autofluorescence of cell walls can be detected in rice. The resolution of images of conventional SEM leaf samples was generally higher than the Coolstage images at the same magnification, whereas local collapse and shrinkage were observed in leaves with high water content when using the conventional method. However, stomatal apparatuses of Arabidopsis, cucumber, radish, and maize deformed and showed poor appearance when using the Coolstage. Moreover, we usually used glutaraldehyde as an SEM fixative when using t-butanol for freeze-drying, though methanol is considered a better fixative in recent studies. In addition, fresh samples were not stable on the Coolstage. Thus, we compared four different t-butanol freeze-drying methods and two Coolstage methods. The dimension and morphology of tissues were compared using the six different methods. The results indicate that methanol fixative obviously reduced shrinkage of SEM samples compared with glutaraldehyde and formaldehyde alcohol acetic acid (FAA) fixatives. The use of methanol and a graded series of steps improved the preservation of samples. Preparing samples with optimal cutting temperature compound and observing at -30°C helped to increase the stability of Coolstage samples. In summary, our results provide an overview of the shortcomings and merits of four different methods, and might provide some information about choosing an optimal method for visualizing epidermal morphology.

5.
Angew Chem Int Ed Engl ; 58(12): 3834-3837, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30600879

RESUMO

Cryosurgery has attracted much attention for the treatment of tumors owing to its clear advantages. However, determining the volume of frozen tissues in real-time remains a challenge, which greatly lowers the therapeutic efficacy of cryosurgery and hinders its broad application for the treatment of cancers. Herein, we report a freezing-induced turn-on strategy for the selective real-time imaging of frozen cancer cells. As a type of aggregation-induced emission (AIE) fluorogen, TABD-Py molecules interact specifically with ice crystals and form aggregates at the ice/water interface. Consequently, bright fluorescent emission appears upon freezing. TABD-Py molecules are enriched mostly in the cancer cells and exhibit high biocompatibility as well as low cytotoxicity; therefore, a freezing-induced turn-on imaging modality for cryosurgery is developed, which will certainly maximize the therapeutic efficacy of cryosurgery in treating tumors.


Assuntos
Criocirurgia/métodos , Piridinas/química , Animais , Corantes Fluorescentes/química , Células HeLa , Humanos , Gelo , Camundongos , Microscopia Confocal , Células NIH 3T3 , Piridinas/síntese química
6.
ACS Appl Mater Interfaces ; 10(28): 23667-23673, 2018 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-29932319

RESUMO

A novel "turn-on" fluorescent bioprobe, 1,2,3,4,5-penta(4-carboxyphenyl)pyrrole sodium salt (PPPNa), with aggregation-enhanced emission characteristics was synthesized for the in situ quantitative detection of Al3+ in serum. It exhibited a high selectivity to Al3+ in both simulated serum and fetal calf serum with no interferences from other metal ions or serum components observed and no isolation required. A weak interaction between PPPNa and serum albumin was found, which caused no interference, but enhanced fluorescence response of PPPNa to Al3+ and improved detection sensitivity. The limit of detection was determined to be 1.50 µmol/L Al3+ in phosphate-buffered saline solution containing 33 µg/mL bovine serum albumin (BSA) and decreased to 0.98 µmol/L as BSA concentration increased to 100 µg/mL. The fluorescence "turn-on" mechanism of the PPPNa probe to detect Al3+ was proposed. A bidentate complex is formed between the carboxy group of PPPNa and Al3+, causing the photoluminescence (PL) emission enhancement by aggregation. BSA chains further strengthen the stacking compactness of the aggregates of PPPNa and Al3+ and consequently enhance the PL emission of PPPNa by further promoting the restriction of intramolecular rotation of the phenyl ring. Its application to the in situ Al3+ was successfully demonstrated with HeLa cells and NIH 3T3 cells. The low cytotoxicity and highly selective response of PPPNa to Al3+ endow its great potentials to in vivo detecting and imaging of Al3+ as well as an absorbent of Al3+.


Assuntos
Alumínio/sangue , Animais , Linhagem Celular , Corantes Fluorescentes , Humanos , Camundongos , Espectrometria de Fluorescência
7.
Anal Bioanal Chem ; 408(4): 1125-35, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26677023

RESUMO

Gestational diabetes mellitus (GDM) refers to the first sign or onset of diabetes mellitus during pregnancy rather than progestation. In recent decades, more and more research has focused on the etiology and pathogenesis of GDM in order to further understand GDM progress and recovery. Using an advanced metabolomics platform based on ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS), we explored the changes in serum metabolites between women with GDM and healthy controls during and after pregnancy. Some significant differences were discovered using multivariate analysis including partial least-squares discriminant analysis (PLS-DA) and orthogonal PLS-DA (OPLS-DA). The dysregulated metabolites were further compared and verified in several databases to understand how these compounds might function as potential biomarkers. Analyses of the metabolic pathways associated with these potential biomarkers were subsequently explored. A total of 35 metabolites were identified, contributing to GDM progress to some extent. The identified biomarkers were involved in some important metabolic pathways including glycine, serine, and threonine metabolism; steroid hormone biosynthesis; tyrosine metabolism; glycerophospholipid metabolism; and fatty acid metabolism. The above mentioned metabolic pathways mainly participate in three major metabolic cycles in humans, including lipid metabolism, carbohydrate metabolism, and amino acid metabolism. In this pilot study, the valuable comprehensive analysis gave us further insight into the etiology and pathophysiology of GDM, which might benefit the feasibility of a rapid, accurate diagnosis and reasonable treatment as soon as possible but also prevent GDM and its related short- and long-term complications.


Assuntos
Biomarcadores/sangue , Cromatografia Líquida/métodos , Diabetes Gestacional/sangue , Espectrometria de Massas/métodos , Adulto , Estudos de Casos e Controles , Análise Discriminante , Feminino , Humanos , Redes e Vias Metabólicas , Metabolômica/métodos , Análise Multivariada , Projetos Piloto , Gravidez , Soro/metabolismo
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