Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
Tree Physiol ; 44(1)2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38102768

RESUMO

Leaf nutrient resorption and drought resistance are crucial for the growth and survival of plants. However, our understanding of the relationships between leaf nutrient resorption and plant drought resistance is still limited. In this study, we investigated the nitrogen and phosphorus resorption efficiencies (NRE and PRE), leaf structural traits, leaf osmotic potential at full hydration (Ψosm), xylem water potential at 50% loss of xylem-specific hydraulic conductivity (P50) and seasonal minimum water potential (Ψmin) for 18 shrub and tree species in a semiarid savanna ecosystem, in Southwest China. Our results showed that NRE and PRE exhibited trade-off against drought resistance traits (Ψosm and P50) across woody species. Moreover, this relationship was modulated by leaf structural investment. Species with low structural investment (e.g., leaf mass per area, leaf dry mass content and leaf construction cost [LCC]) tend to have high NRE and PRE, while those with high LCCs show high drought resistance, showing more negative Ψosm and P50.These results indicate that species with a lower leaf structural investment may have a greater need to recycle their nutrients, thus exhibiting higher nutrient resorption efficiencies, and vice versa. In conclusion, nutrient resorption efficiency may be a crucial adaptation strategy for coexisting plants in semiarid ecosystems, highlighting the importance of understanding the complex relationships between nutrient cycling and plant survival strategies.


Assuntos
Ecossistema , Pradaria , Resistência à Seca , Nitrogênio/análise , Fósforo/análise , Plantas , Árvores , China , Água , Folhas de Planta/química
2.
Environ Sci Pollut Res Int ; 30(53): 113948-113961, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37858011

RESUMO

The impact of exposure to metals on chronic kidney disease (CKD) has only been investigated in two-way or single metal interactions in previous studies. We investigated the associations between five single metals in blood and their mixed exposure and CKD by using the machine learning approach. Relevant data were extracted from the National Health and Nutrition Examination Survey (NHANES 2011-2020), and the level of five metals in blood detected by inductively coupled plasma mass spectrometry was considered as exposures, namely, cadmium (Cd), lead (Pb), total mercury (Hg), manganese (Mn), and selenium (Se). The correlations between individual metal and metal mixtures and CKD were then evaluated by survey-multivariable logistic regression (SMLR), generalized weighted quantile sum (WQS), and Bayesian kernel machine regression (BKMR). Altogether, our study included 12,412 participants representing 572.6 million non-institutionalized US adults. Several single metals with the high quartile of exposure showed a positive association with the CKD ratio including Cd [(AOR = 1.873, 95% CI: 1.537, 2.284), Q4], Pb [(AOR = 1.559, 95% CI: 1.295, 1.880), Q4], and total Hg [(AOR = 1.169, 95% CI: 1.018, 1.343), Q2], while Mn [(AOR = 0.796, 95% CI: 0.684, 0.927), Q2] and Se [(AOR = 0.805, 95% CI: 0.664, 0.976), Q4] were negatively associated with the CKD ratio. In light of the positive fit of the WQS regression model, a significantly positive correlation was found between mixed metals and CKD (AOR = 1.373, 95% CI: 1.224, 1.539) after full covariate adjustment, and a similar finding was also detected in the BKMR model. Our study revealed that each single metal including Cd, Pb, and total Hg might have a positive association with CKD while this association was negative for both Mn and Se. The five metals might have a positive joint effect on CKD.


Assuntos
Mercúrio , Metais Pesados , Insuficiência Renal Crônica , Selênio , Adulto , Humanos , Inquéritos Nutricionais , Estudos Transversais , Cádmio , Teorema de Bayes , Chumbo , Manganês , Insuficiência Renal Crônica/epidemiologia
3.
Environ Sci Pollut Res Int ; 30(42): 96604-96616, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37578581

RESUMO

With little knowledge on the joint effects of metal exposure on dyslipidemia, we aimed to investigate the relationship between exposure to metal and dyslipidemia among US adults based on the National Health and Nutrition Examination Survey (NHANES). Based on the five NHANES waves (2011-2020), we selected five metals in blood as exposure, namely, cadmium (Cd), lead (Pb), total mercury (Hg), manganese (Mn), and selenium (Se), which were detected by inductively coupled plasma mass spectrometry. Survey-multivariable logistic regression, generalized weighted quantile sum (WQS), and Bayesian kernel machine regression (BKMR) were performed to determine whether dyslipidemia was associated with single metals or mixed metals. Our study included 12,526 participants aged from 20 to 80, representing 577.1 million non-institutionalized US adults. We found a positive association between several metals including Pb [adjusted odds ratio (AOR) = 1.332, 95%CI: 1.165, 1.522], total Hg (AOR = 1.264, 95%CI: 1.120, 1.427), Mn (AOR = 1.181, 95%CI: 1.046, 1.334), and Se (AOR = 1.771, 95%CI: 1.576, 1.992) and dyslipidemia. According to the WQS approach, metal mixtures were positively associated with dyslipidemia (AOR: 1.310, 95%CI: 1.216, 1.411) after a full-model adjustment. As is shown in the BKMR model, mixed metals tended to be positively associated with dyslipidemia ratios in a significant manner. Females, non-Hispanic White populations, people aged over 60, and those who did a little physical activity had a greater risk for dyslipidemia. Our findings suggest metals including Cd, Pb, Hg, Mn, and Se and their combinations may adversely affect dyslipidemia among US adults. Due to the cross-sectional nature of the study, it is possible that reverse causation may exist.


Assuntos
Mercúrio , Metais Pesados , Selênio , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Cádmio , Inquéritos Nutricionais , Teorema de Bayes , Estudos Transversais , Chumbo , Manganês
4.
JAMA Pediatr ; 177(2): 132-140, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36595284

RESUMO

Importance: Depression is the second most prevalent mental disorder among children and adolescents, yet only a small proportion seek or receive disorder-specific treatment. Physical activity interventions hold promise as an alternative or adjunctive approach to clinical treatment for depression. Objective: To determine the association of physical activity interventions with depressive symptoms in children and adolescents. Data Sources: PubMed, CINAHL, PsycINFO, EMBASE, and SPORTDiscus were searched from inception to February 2022 for relevant studies written in English, Chinese, or Italian. Study Selection: Two independent researchers selected studies that assessed the effects of physical activity interventions on depressive symptoms in children and adolescents compared with a control condition. Data Extraction and Synthesis: A random-effects meta-analysis using Hedges g was performed. Heterogeneity, risk of bias, and publication bias were assessed independently by multiple reviewers. Meta-regressions and sensitivity analyses were conducted to substantiate the overall results. The study followed the PRISMA reporting guideline. Main Outcomes and Measures: The main outcome was depressive symptoms as measured by validated depression scales at postintervention and follow-up. Results: Twenty-one studies involving 2441 participants (1148 [47.0%] boys; 1293 [53.0%] girls; mean [SD] age, 14 [3] years) were included. Meta-analysis of the postintervention differences revealed that physical activity interventions were associated with a reduction in depressive symptoms compared with the control condition (g = -0.29; 95% CI, -0.47 to -0.10; P = .004). Analysis of the follow-up outcomes in 4 studies revealed no differences between the physical activity and control groups (g = -0.39; 95% CI, -1.01 to 0.24; P = .14). Moderate study heterogeneity was detected (Q = 53.92; df = 20; P < .001; I2 = 62.9% [95% CI, 40.7%-76.8%]). The primary moderator analysis accounting for total physical activity volume, study design, participant health status, and allocation and/or assessment concealment did not moderate the main treatment effect. Secondary analyses demonstrated that intervention (ie, <12 weeks in duration, 3 times per week, unsupervised) and participant characteristics (ie, aged ≥13 years, with a mental illness and/or depression diagnosis) may influence the overall treatment effect. Conclusions and Relevance: Physical activity interventions may be used to reduce depressive symptoms in children and adolescents. Greater reductions in depressive symptoms were derived from participants older than 13 years and with a mental illness and/or depression diagnosis. The association with physical activity parameters such as frequency, duration, and supervision of the sessions remains unclear and needs further investigation.


Assuntos
Depressão , Transtornos Mentais , Masculino , Feminino , Humanos , Criança , Adolescente , Depressão/prevenção & controle , Depressão/diagnóstico , Exercício Físico , Promoção da Saúde , Nível de Saúde
5.
Food Chem ; 285: 414-422, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30797365

RESUMO

Buckwheat constitutes a good source of bioactive components. A dry fractionation of surface abrasion for polyphenol-enriched protein combined with hydrothermal treatment was evaluated as an alternative to conventional wet extraction from tartary buckwheat (Fagopyrum esculentum Moench). The protein contents and the total polyphenol contents of both free and bound polyphenol gradually decreased in the order from the outer to the inner fractions. Polyphenol-enriched buckwheat protein flour was successfully enrichment with a maximum polyphenol content of 55 mg/g. Moreover, starch digestibility and polyphenols bioaccessibility of the buckwheat protein were increased with hydrothermal treatment time, while protein digestibility decreased slightly. Besides, most of the aroma compounds increased during the hydrothermal treatment. The assessment results demonstrate that the sustainability dry surface abrasion process in combination with hydrothermal treatment should be encouraged in processing functional protein fractions and improving both qualities of end use products and health benefits.


Assuntos
Fracionamento Químico/métodos , Fagopyrum/química , Manipulação de Alimentos/métodos , Proteínas de Plantas/química , Polifenóis/química , Proteínas Alimentares/química , Farinha , Manipulação de Alimentos/instrumentação , Alimentos Fortificados , Proteínas de Plantas/farmacocinética , Polifenóis/análise , Polifenóis/farmacocinética , Amido
6.
J Sci Food Agric ; 99(6): 3176-3185, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30548612

RESUMO

BACKGROUND: During the last decade buckwheat was reported to have positive health effects. The present study investigated a high-polyphenol buckwheat protein (Fagopyrum esculentum Moench) prepared by enzyme-assisted processing, together with its physicochemical properties, in vitro digestibility, and antioxidant activity. RESULTS: Buckwheat protein prepared from the synergistic enzymatic action of α-amylase and amyloglucosidase (E-BWP) had much higher polyphenol content than buckwheat protein prepared by isoelectric precipitation (I-BWP) or salt extraction (S-BWP). Rutin degraded during the process, giving quercetin. The protein constituents and amino acid composition of E-BWP were very similar to those of native buckwheat and were able to meet the WHO/FAO requirements for both children and adults. During in vitro digestion, E-BWP showed anti-digestive behavior with a nitrogen release that was lower than that of I-BWP or S-BWP. The positive effect of the polyphenol content of E-BWP resulted in a higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) content and greater reducing activity. CONCLUSION: Buckwheat protein with high polyphenol content was successfully developed by enzyme-assisted processing. It had a well-balanced amino acid profile, antidigestive behavior, and high antioxidant activities. The results suggest that enzyme-assisted processing is promising in the production of polyphenol-enriched cereal protein, contributing higher functionality with good nutritional and antioxidant properties. © 2018 Society of Chemical Industry.


Assuntos
Antioxidantes/química , Fagopyrum/química , Fagopyrum/metabolismo , Glucana 1,4-alfa-Glucosidase/química , Proteínas de Plantas/química , Polifenóis/análise , alfa-Amilases/química , Antioxidantes/metabolismo , Biocatálise , Digestão , Manipulação de Alimentos , Humanos , Proteínas de Plantas/metabolismo , Polifenóis/metabolismo , Sementes/química , Sementes/metabolismo
7.
Food Funct ; 7(9): 3694-702, 2016 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-27501908

RESUMO

Algae oil, enriched with omega-3 long-chain polyunsaturated fatty acids (ω-3 LC-PUFA), is known for its health benefits. However, protection against lipid oxidation as well as masking of unpleasant fishy malodors in algae oil enriched foods is a big challenge to achieve. In this study, we firstly achieved a one-pot ultrasound emulsification strategy (alternative heating-homogenization) to prepare phytosterol structured thermosensitive algae oil-in-water nanoemulsion stabilized by quillaja saponin. After spray drying, the resulting algae oil powders from the structured nanoemulsion templates exhibit an excellent reconstructed behavior, even after 30 d of storage. Furthermore, an enhanced oxidative stability was obtained by reducing both the primary and secondary oxidation products through formulation with ß-sitosterol and γ-oryzanol, which are natural antioxidants. Following the results of headspace volatiles using dynamic headspace-gas chromatography-mass spectrometry (DHS-GC-MS), it was clear that the structured algae oil-loaded nanoemulsion and powder had lower levels of fishy off-flavour (e.g., (Z)-heptenal, decanal, ethanone, and hexadecenoic acid), whereas the control emulsion and oil powder without structure performed worse. This study demonstrated that the structure from phytosterols is an effective strategy to minimize the fishy off-flavour and maximize oxidative stability of both algae oil nanoemulsions and spray-dried powders, and opens up the possibility of formulation design in polyunsaturated oil encapsulates as novel delivery systems to apply in functional foods and beverages.


Assuntos
Antioxidantes/análise , Emulsões/química , Ácidos Graxos Ômega-3/química , Óleos/química , Fitosteróis/química , Paladar , Estabilidade de Medicamentos , Alimentos Fortificados , Odorantes/análise , Fenilpropionatos , Pós , Saponinas de Quilaia , Sitosteroides
8.
World J Gastroenterol ; 16(12): 1512-7, 2010 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-20333793

RESUMO

AIM: To determine the glycemic index (GI) and glycemic load (GL) values of Chinese traditional foods in Hong Kong. METHODS: Fifteen healthy subjects (8 males and 7 females) volunteered to consume either glucose or one of 23 test foods after 10-14 h overnight fast. The blood glucose concentrations were analyzed immediately before, 15, 30, 45, 60, 90 and 120 min after food consumption using capillary blood samples. The GI value of each test food was calculated by expressing the incremental area under the blood glucose response curve (IAUC) value for the test food as a percentage of each subject's average IAUC value for the glucose. The GL value of each test food was calculated as the GI value of the food multiplied by the amount of the available carbohydrate in a usual portion size, divided by 100. RESULTS: Among all the 23 Chinese traditional foods tested, 6 of them belonged to low GI foods (Tuna Fish Bun, Egg Tart, Green Bean Dessert, Chinese Herbal Jelly, Fried Rice Vermicelli in Singapore-style, and Spring Roll), 10 of them belonged to moderate GI foods (Baked Barbecued Pork Puff, Fried Fritter, "Mai-Lai" Cake, "Pineapple" Bun, Fried Rice Noodles with Sliced Beef, Barbecue Pork Bun, Moon Cakes, Glutinous Rice Ball, Instant Sweet Milky Bun, and Salted Meat Rice Dumpling), the others belonged to high GI foods (Fried Rice in Yangzhou-Style, Sticky Rice Wrapped in Lotus Leaf, Steamed Glutinous Rice Roll, Jam and Peanut Butter Toast, Plain Steamed Vermicelli Roll, Red Bean Dessert, and Frozen Sweet Milky Bun). CONCLUSION: The GI and GL values for these Chinese traditional foods will provide some valuable information to both researchers and public on their food preference.


Assuntos
Povo Asiático/estatística & dados numéricos , Glicemia/metabolismo , Dieta/etnologia , Carboidratos da Dieta/metabolismo , Índice Glicêmico , Adulto , China , Carboidratos da Dieta/administração & dosagem , Feminino , Humanos , Masculino , Fatores de Tempo
9.
Nan Fang Yi Ke Da Xue Xue Bao ; 28(12): 2126-30, 2008 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-19114337

RESUMO

OBJECTIVE: To study the role of extracellular matrix (ECM) in neural differentiation of mouse embryonic stem cells (ESCs). METHODS: Mouse ESCs were incubated in the ESC conditioned medium, and the formation of embryonic bodies (EBs) were induced in bacteriological dishes using high-concentration all-trans retinoic acid (RA). The EBs were seeded on different matrixes (gelatin, fibronectin, and laminin/poly-L-ornithine) to test their impact on neural differentiation of the ESCs using immunofluorescence assay. The effect of laminin/poly-L-ornithine on the growth of neurites was evaluated with fluorescence microscopy. RESULTS: High-concentration RA activated and accelerated the differentiation of ESCs toward nestin-positive neural progenitor cells. Fibronectin supplement in the matrix dose-dependently promoted ESC differentiation into neural progenitor cells, while laminin/poly-L-ornithine increased the growth of the neurites and induced the maturation of the differentiated neural cells. CONCLUSION: ECM plays an important role in neural differentiation of mouse ESCs, and application of FN produces the most conspicuous effect during the differentiation of the ESCs into the neural progenitor cells;laminin/poly-L-ornithine is the most effective during their differentiation into neural cells.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Células-Tronco Embrionárias/citologia , Matriz Extracelular/fisiologia , Neurônios/citologia , Animais , Células Cultivadas , Meios de Cultura , Células-Tronco Embrionárias/efeitos dos fármacos , Fibronectinas/farmacologia , Laminina/farmacologia , Camundongos , Neurônios/efeitos dos fármacos , Peptídeos/farmacologia , Tretinoína/farmacologia
10.
Zhongguo Zhong Yao Za Zhi ; 32(18): 1874-6, 2007 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-18051893

RESUMO

OBJECTIVE: Several cryoprotectants were employed to study the protective effect on the freeze-drying process of the oleanolic acid-loaded nanosuspensions (OLA-LS) in order to select the optimum formulation. METHOD: The protective effect was evaluated by measuring the mean particle size of samples before and after freeze-drying process. RESULT: Sucrose with the concentration of 10% was selected as the optimum cryoprotectant. The average size of excellent sample was 236.3 nm (versus 211.2 nm of fresh one), and a much higher polydispersity index of 0.242 (versus 0.180). CONCLUSION: The optimum lyophilized powder could be obtained with suitable type of cryoprotectant with appropriate concentration and proper freeze-drying conditions.


Assuntos
Liofilização/métodos , Nanopartículas/química , Ácido Oleanólico/química , Crioprotetores/química , Crioprotetores/farmacologia , Estabilidade de Medicamentos , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Tamanho da Partícula , Solubilidade/efeitos dos fármacos , Sacarose/química , Sacarose/farmacologia , Suspensões
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA