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1.
Front Neurosci ; 18: 1401530, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38741786

RESUMEN

Introduction: Sleep insufficiency has been linked to an increased risk of high blood pressure and cardiovascular diseases. Emerging studies have demonstrated that impaired baroreflex sensitivity (BRS) is involved in the adverse cardiovascular effects caused by sleep deprivation, however, the underlying mechanisms remain unknown. Therefore, the present study aims to clarify the role of abnormal renin-angiotensin system in the nucleus tractus solitarii (NTS) in impaired BRS induced by sleep deprivation. Methods: Rats were randomly divided into two groups: normal sleep (Ctrl) and chronic sleep deprivation (CSD) group. Rats were sleep deprived by an automated sleep deprivation system. The blood pressure, heart rate, BRS, the number of c-Fos positive cells and the expression of angiotensin (Ang) II subtype 1 receptors (AT1R) in the NTS of rats were assessed. Results: Compared to Ctrl group, CSD group exhibited a higher blood pressure, heart rate, and reduced BRS. Moreover, the number of c-Fos positive cells and local field potential in the NTS in CSD group were increased compared with the Ctrl group. It was shown that the expression of the AT1R and the content of Ang II and the ratio of Ang II to Ang-(1-7) were increased in the NTS of rats in CSD group compared to Ctrl group. In addition, microinjection of losartan into the NTS significantly improved the impaired BRS caused by sleep deprivation. Discussion: In conclusion, these data suggest that the elevated AT1R expression in the NTS mediates the reduced BRS induced by chronic sleep deprivation.

2.
Foods ; 13(2)2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38254521

RESUMEN

A popular non-alcoholic beverage worldwide, tea can regulate blood glucose levels, lipid levels, and blood pressure, and may even prevent type 2 diabetes mellitus (T2DM). Different tea fermentation levels impact these effects. Tea products with different fermentation degrees containing different functional ingredients can lower post-meal blood glucose levels and may prevent T2DM. There are seven critical factors that shed light on how teas with different fermentation levels affect blood glucose regulation in humans. These factors include the inhibition of digestive enzymes, enhancement of cellular glucose uptake, suppression of gluconeogenesis-related enzymes, reduction in the formation of advanced glycation end products (AGEs), inhibition of dipeptidyl peptidase-4 (DPP-4) activity, modulation of gut flora, and the alleviation of inflammation associated with oxidative stress. Fermented teas can be used to lower post-meal blood glucose levels and can help consumers make more informed tea selections.

3.
Sci Rep ; 13(1): 20964, 2023 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-38017306

RESUMEN

Acetylation could improve the bioavailability of (-)-Epigallocatechin-3-Gallate (EGCG), but the relationship of substitution degree and antioxidant capacity of acetylated EGCG was unclear. The acetylated EGCG products were separated by preparation high performance liquid chromatography (HPLC). Two mono substituted acetylated EGCG, three substituted acetylated EGCG (T-AcE), eight substituted acetylated EGCG (E-AcE) and (-)-Epigallocatechin gallate (EGCG) were isolated. The 7-acetyl-EGCG (S7-ACEGCG) and 7-acetyl-EGCG (T-AcE) were identified for the first time. The antioxidant capacity, superoxide anion radical scavenging capacities, and hydroxyl radical scavenging capacities of EGCG decreased significantly after acetylation modification. The more EGCG acetylation modification sites, the lower the total antioxidant capacity, superoxide anion radical scavenging capacities, and hydroxyl radical scavenging capacities. The antioxidant capacity, superoxide anion radical scavenging capacities, and hydroxyl radical scavenging capacities of 5-acetyl-EGCG (S5-ACE) were higher than 7-acetyl-EGCG (S7-AcE). Combining all the results in this and previous studies, acetylation modification is not conducive to the performance of EGCG antioxidant capacity.


Asunto(s)
Antioxidantes , Catequina , Antioxidantes/farmacología , Antioxidantes/química , Superóxidos/química , Radical Hidroxilo , Catequina/química
4.
Phys Chem Chem Phys ; 25(34): 22782-22793, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37584079

RESUMEN

With the continuous miniaturization and integration of spintronic devices, the two-dimensional (2D) ferromagnet coupling of ferromagnetic and diverse electrical properties has become increasingly important. Herein, we report three ferromagnetic monolayers: GdS2, GdSe2 and Janus GdSSe. They are bipolar magnetic semiconductors and demonstrate ferroelasticity with a large reversible strain of 73.2%. Three monolayers all hold large magnetic moments of about 8µB f.u.-1 and large spin-flip energy gaps in both the conduction and valence bands, which are highly desirable for applications in bipolar field effect spin filters and spin valves. Our calculations have testified to the feasibility of the experimental achievement of the three monolayers and their stability. Additionally, intrinsic valley polarization occurs in the three monolayers owing to the cooperative interplay between spin-orbit coupling and magnetic exchange interaction. Moreover, we identified square lattices for GdS2 and GdSe2 monolayers. The new and stable square lattices of GdS2 and GdSe2 monolayers show robust ferromagnetism with high Curie temperatures of 648 and 312 K, respectively, and the characteristics of spin-gapless semiconductors. Overall, these findings render GdS2, GdSe2 and Janus GdSSe monolayers promising candidate materials for multifunctional spintronic devices at the nanoscale.

5.
Nutrients ; 15(3)2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36771313

RESUMEN

Gut microbiota is the largest and most complex microflora in the human body, which plays a crucial role in human health and disease. Over the past 20 years, the bidirectional communication between gut microbiota and extra-intestinal organs has been extensively studied. A better comprehension of the alternative mechanisms for physiological and pathophysiological processes could pave the way for health. Cardiovascular disease (CVD) is one of the most common diseases that seriously threatens human health. Although previous studies have shown that cardiovascular diseases, such as heart failure, hypertension, and coronary atherosclerosis, are closely related to gut microbiota, limited understanding of the complex pathogenesis leads to poor effectiveness of clinical treatment. Dysregulation of inflammation always accounts for the damaged gastrointestinal function and deranged interaction with the cardiovascular system. This review focuses on the characteristics of gut microbiota in CVD and the significance of inflammation regulation during the whole process. In addition, strategies to prevent and treat CVD through proper regulation of gut microbiota and its metabolites are also discussed.


Asunto(s)
Enfermedades Cardiovasculares , Microbioma Gastrointestinal , Hipertensión , Probióticos , Humanos , Enfermedades Cardiovasculares/prevención & control , Probióticos/uso terapéutico , Hipertensión/etiología , Inflamación/complicaciones , Prebióticos
6.
Foods ; 11(21)2022 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-36360052

RESUMEN

Combined with the unique processing technology of oolong tea, oolong tea with stem processing has a better flavor compared to oolong tea without stem processing. However, there is currently no available evidence to support the contribution of stems to the taste quality of oolong tea. In this study, the electronic tongue, sensory evaluation method combined with liquid chromatography, and gas chromatography−mass spectrometry were used to explore the influence of the presence of stems on the flavor substances and aroma of oolong tea during processing. The results showed that the presence of stems significantly increased the umami taste of oolong tea (p < 0.05), and the content of seven free amino acids (p < 0.05), including theanine (53.165 µg/mL) and aspartic acid (3.190 µg/mL), two umami-related amino acids, significantly increased. Moreover, the content of nerolidol (2.598 µg/g) in aroma components was significantly increased. This study identifies the contribution of stems to oolong tea quality during processing.

7.
ACS Omega ; 7(3): 3060-3063, 2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-35097300

RESUMEN

Taking aryl propargyl ether and o-iodibenzoic acid as substrates, a series of aryl cyclolactones bearing an exocyclized C=C bond were constructed with moderate to good yields. Diverse substituent groups could be tolerant in the reaction, which indicated excellent compatibility of the reaction. In this tandem reaction, Ag2O was employed as the media and Et3N was screened as the base to facilitate the reaction. A concise mechanism was proposed on the basis of the expansion of the substrates and theoretical analysis. Sonogashira type coupling coupled with intramolecular nucleophilic addition in one pot to construct the product, 3-ethylideneisobenzofuran-1(3H)-one.

8.
J Sci Food Agric ; 102(4): 1628-1639, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-34420207

RESUMEN

BACKGROUND: Red light withering significantly improves the sensory flavor qualities of tea, although changes in metabolites during this process have not been systematically studied until now. The present study comprehensively analyzes metabolites in withered tea leaves at 2-h intervals up to 12 h under red light (630 nm) and dark conditions using ultra performance liquid chromatography-high resolution mass spectrometry (untargeted metabolomics). RESULTS: Ninety-four non-volatile compounds are identified and relatively quantified, including amino acids, catechins, dimeric catechins, flavonol glycosides, glycosidically-bound volatiles, phenolic acids and nucleosides. The results show that amino acids, catechins and dimeric catechins are most affected by red light treatment. Ten free amino acids, theaflavins and theasinensin A increase after red light irradiation, whereas epigallocatechin gallate and catechin fall. CONCLUSION: The present study provides a comprehensive and systematic profile of the dynamic effects of red light on withering tea and a rationale for its use in tea processing quality control. © 2021 Society of Chemical Industry.


Asunto(s)
Camellia sinensis , Catequina , Catequina/análisis , Cromatografía Liquida , Metabolómica , Hojas de la Planta/química ,
9.
Huan Jing Ke Xue ; 41(6): 2918-2923, 2020 Jun 08.
Artículo en Chino | MEDLINE | ID: mdl-32608809

RESUMEN

Glaciers are constantly retreating because of global warming. In this study, three soil samples along the forefield of Urumqi Glacier No. 1 were collected. The effects of warming on the microbial community in the glacier forefield were investigated through a 150-day laboratory experiment. In this experiment, two temperature treatments were performed at 5℃and 15℃. The results showed that with increasing deglaciation age, the concentrations of carbon and nitrogen increased and the abundance and alpha diversity of microbial communities increased in the original samples. The 150-day laboratory experiment indicated that warming insignificantly changed the copy number of archaea and bacteria. Furthermore, it changed the microbial community composition, and the changes varied in different sampling sites. Based on the analysis of abundant OTUs changing significantly with warming, the sampling sites with shorter deglaciation age had stronger response with warming, representing an increase in the abundance of genus Thiobacillus. Furthermore, these results revealed that warming caused different effects on microbes along glacier forefield and thus, it could provide important characteristics of the microbial community with warming in alpine glacier regions.


Asunto(s)
Cubierta de Hielo , Microbiota , Bacterias , Suelo , Microbiología del Suelo
10.
Glob Chang Biol ; 26(2): 697-708, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31782204

RESUMEN

Mountain glaciers are retreating at an unprecedented rate due to global warming. Glacier retreat is widely believed to be driven by the physiochemical characteristics of glacier surfaces; however, the current knowledge of such biological drivers remains limited. An estimated 130 Tg of organic carbon (OC) is stored in mountain glaciers globally. As a result of global warming, the accelerated microbial decomposition of OC may further accelerate the melting process of mountain glaciers by heat production with the release of greenhouse gases, such as carbon dioxide (CO2 ) and methane. Here, using short-term aerobic incubation data from the forefield of Urumqi Glacier No. 1, we assessed the potential climate feedback mediated by soil microbiomes at temperatures of 5°C (control), 6.2°C (RCP 2.6), 11°C (RCP 8.5), and 15°C (extreme temperature). We observed enhanced CO2 -C release and heat production under warming conditions, which led to an increase in near-surface (2 m) atmospheric temperatures, ranging from 0.9°C to 3.4°C. Warming significantly changed the structures of the RNA-derived (active) and DNA-derived (total) soil microbiomes, and active microbes were more sensitive to increased temperatures than total microbes. Considering the positive effects of temperature and deglaciation age on the CO2 -C release rate, the alterations in the active microbial community structure had a negative impact on the increased CO2 -C release rate. Our results revealed that glacial melting could potentially be significantly accelerated by heat production from increased microbial decomposition of OC. This risk might be true for other high-altitude glaciers under emerging warming, thus improving the predictions of the effects of potential feedback on global warming.


Asunto(s)
Gases de Efecto Invernadero , Microbiota , Calentamiento Global , Cubierta de Hielo , Suelo
11.
FEMS Microbiol Ecol ; 95(8)2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31281933

RESUMEN

To understand the response of soil microbial communities in different types of wetlands to anthropogenic disturbances, this study focused on a freshwater wetland (Sanjiang Wetland) and a salt marsh (Momoge Wetland) and sampled cultivated, degraded, and natural soils in these wetlands. High-throughput sequencing was applied to characterize the soil microbial community composition, and physicochemical properties, including pH, total nitrogen, total carbon, and soil water content (SWC), were measured. The results revealed that the total nitrogen, total carbon, and SWC were significantly lower in disturbed soil in the freshwater wetland but higher in the salt marsh. Generally, under anthropogenic disturbances, microbial community diversity decreased in the freshwater wetland and increased in the salt marsh. The bacterial community structure in the salt marsh was more sensitive than that in the freshwater wetland, while the fungal community structure in the freshwater wetland was more susceptible than that in the salt marsh. The results of indicator value analyses revealed specific issues in two wetlands, such as methane generation and anoxic conditions. This study shows that soil microbiomes in two types of wetlands respond differently to human activities, which implies that the type of native wetlands should be considered in the exploitation of wetlands.


Asunto(s)
Agua Dulce/microbiología , Microbiota/genética , Microbiología del Suelo , Humedales , Carbono/análisis , China , Nitrógeno/análisis , Suelo/química
12.
Food Funct ; 10(6): 3502-3513, 2019 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-31143917

RESUMEN

Obesity is a chronic metabolic disorder that is associated with higher risks of developing diabetes and cardiovascular disease. Chinese dark tea is a fermented beverage with many biological effects and could be considered for the management of obesity. This study is aimed to assess the possible anti-obesity properties of instant dark tea (IDT) and instant pu-erh tea (PET) in high fat diet (HFD)-fed mice. Male C57BL/6 mice were divided into 5 groups. They received low-fat diet (LFD), HFD, HFD supplemented with drinking IDT infusion (5 mg mL-1), PET infusion (5 mg mL-1) or water for 8 weeks. The results showed IDT exhibited better inhibitory effect than PET on body weight gain and visceral fat weights. IDT also improved the serum high-density lipoprotein cholesterol (HDL-C) level, but decreased the low-density lipoprotein cholesterol (LDL-C) and leptin levels more effectively than PET. Both IDT and PET lowered the levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the plasma and significantly increased the ratio of albumin to globin (A/G) in the serum compared to the control group. IDT treatment reduced the malondialdehyde (MDA) level in the liver. Histomorphology evidenced that the liver tissue architecture was well preserved by IDT administration. Moreover, IDT regulated the expression of obesity-related genes more effectively than PET. Overall, the present findings have provided the proof of concept that dietary IDT could provide a safer and cost-effective option for people with HFD-induced obesity.


Asunto(s)
Fármacos Antiobesidad/metabolismo , Obesidad/dietoterapia , Extractos Vegetales/metabolismo , Alanina Transaminasa/metabolismo , Animales , Camellia sinensis/química , Camellia sinensis/metabolismo , LDL-Colesterol/metabolismo , Dieta Alta en Grasa/efectos adversos , Alimentos Fermentados/análisis , Humanos , Grasa Intraabdominal/metabolismo , Leptina/metabolismo , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Obesidad/etiología , Obesidad/metabolismo , Té/metabolismo
13.
J Food Sci Technol ; 55(7): 2579-2586, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30042574

RESUMEN

In this study, submerged fermentation mode for preparing instant dark tea production was developed through utilizing industrial low grade green tea as raw material and Aspergillus niger as fermentation microbe starter. The fermentation parameters (inoculum size, liquid-solid ratio and rotation speed) were optimized by using Box-Behnken design and response surface methodology (RSM) with desirability function, the theabrownins content, redness and turbidity value as responses. The optimal conditions were set as follow: inoculum size of 5.3% (v/v), liquid-solid ratio of 27.78 mL/g, and rotation speed of 182 r/min. The optimized conditions model showed a good correlation between the predicted and experimental values. Further, the optimum product of instant dark was achieved in a 3-L laboratory fermenter, and the main parameters of product were theabrownins content of 140.92 g/kg and redness value of 40.78 and turbidity of 90.98 NTU. Sensory evaluation showed that the instant dark tea infusion approached mellow mouthfeel, an aroma of mint and a good overall acceptance.

14.
J Sci Food Agric ; 97(15): 5100-5106, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28422292

RESUMEN

BACKGROUND: Theabrownins (TB) are bioactive components that are usually extracted from Chinese dark tea, in which they are present at low concentrations. The present study aimed to produce an instant dark tea high in theabrownins via submerged fermentation by the fungus Aspergillus niger. Three fermentation parameters that affect theabrownins content (i.e. inoculum size, liquid-solid ratio and rotation speed) were optimized using response surface methodology. RESULT: Optimum fermentation conditions were modeled to be an inoculum of 5.40% (v/v), a liquid-solid ratio of 27.45 mL g-1 and a rotation speed of 184 rpm and were predicted to yield 292.99 g kg-1 TB. Under these experimentally conditions, the TB content of the instant dark tea was 291.93 g kg-1 . The antioxidant capacity and α-glucosidase and pancreatic lipase inhibitory activities of the high-TB instant black tea were higher than four other typical instant dark tea products. CONCLUSION: The results of the present study show that careful management of culture conditions can produce a dark tea high in theabrownins. Furthermore, high-theabrownins instant dark tea could serve as a source of bioactive products and be used in functional foods as an ingredient imparting antioxidant properties and the ability to inhibit pancreatic lipase and α-glucosidase. © 2017 Society of Chemical Industry.


Asunto(s)
Aspergillus niger/metabolismo , Camellia sinensis/microbiología , Catequina/análogos & derivados , Proteínas Fúngicas/metabolismo , Lipasa/química , Té/química , alfa-Glucosidasas/metabolismo , Antioxidantes , Camellia sinensis/química , Camellia sinensis/metabolismo , Catequina/metabolismo , Fermentación , alfa-Glucosidasas/química
15.
Vet Parasitol ; 174(1-2): 72-6, 2010 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-20851527

RESUMEN

Chinese Holstein, bred by mating the Holstein-Friesian to Chinese Yellow Cattle, is a major dairy cattle breed in China. Eprinomectin is widely used in the treatment of nematode and ectoparasite infections in lactating cattle. The pharmacokinetics of eprinomectin in the plasma and milk were determined in Chinese Holstein cows following topical (at 0.5 mg kg(-1)) or oral (at 0.2 mg kg(-1)) administration. For topical administration, the concentrations of eprinomectin in plasma reached peak values (C(max)) of 16.16 ± 6.02 ng ml(-1) at 3.20 ± 1.30 days (T(max)). In milk, the C(max) values of 2.28 ± 0.85 ng ml(-1) were obtained at 3.48 ± 0.65 days. The MRT values were 5.00 ± 0.96 days for plasma and 4.65 ± 0.60 days for milk. The AUC values were 91.00 ± 25.32 ng d ml(-1) for plasma and 10.53 ± 1.55 ng d ml(-1) for milk. The ratio of AUC milk/plasma was 0.124 ± 0.041. Significant differences were found in C(max) and AUC of eprinomectin in plasma between Chinese Holstein and Prim Holstein following topical administration. It was probably due to the lower storage of body fat in Chinese Holstein than in Prim Holstein. For oral administration, the concentrations of eprinomectin reach peak values of 30.02 ± 5.73 ng ml(-1) at 1.60 ± 0.55 days in plasma and 3.14 ± 0.88 ng ml(-1) at 1.40 ± 0.27 days in milk. The MRT values for plasma and milk were 3.00 ± 0.46 and 3.18 ± 0.55 days, respectively. The AUC values were 98.46 ± 24.75 ng d ml(-1) for plasma and 10.42 ± 4.22 ng d ml(-1) for milk. The ratio of AUC milk/plasma was 0.104 ± 0.022. Compared with the topical administration, a significantly shorter MRT of eprinomectin in plasma was obtained following oral administration, which would shorten residue time of this compound in faeces and reduce its ecotoxicological effect. The low exposure of eprinomectin in milk would favor the use of eprinomectin in lactating Chinese Holstein for topical or oral administration.


Asunto(s)
Ivermectina/análogos & derivados , Lactancia , Leche/química , Administración Oral , Administración Tópica , Animales , Bovinos , China , Femenino , Ivermectina/administración & dosificación , Ivermectina/sangre , Ivermectina/farmacocinética
16.
Vet Parasitol ; 137(3-4): 386-90, 2006 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-16473465

RESUMEN

Thirty rabbits naturally infected with ear mange mite, Psoroptes cuniculi, were subcutaneously administrated with a single dose of eprinomectin at 100, 200 and 300 microg/kg body weight or vehicle on day 0. The extent of lesions was scored on day -6 (prior to treatment), day 0 (treated), days 7, 14, 21, 28 and 35, the ear scabs were collected simultaneously; mites in scabs were examined and counted. The results showed that a single dose of eprinomectin at 200 or 300 microg/kg body weight following subcutaneous administration was able to eliminate P. cuniculi infection in rabbits, and a dose of eprinomectin at 100 microg/kg could significantly reduce mites but was unable to eliminate P. cuniculi.


Asunto(s)
Insecticidas/uso terapéutico , Ivermectina/análogos & derivados , Infestaciones por Ácaros/veterinaria , Psoroptidae/efectos de los fármacos , Conejos/parasitología , Animales , Relación Dosis-Respuesta a Droga , Oído/parasitología , Femenino , Inyecciones Subcutáneas/veterinaria , Ivermectina/uso terapéutico , Masculino , Infestaciones por Ácaros/tratamiento farmacológico , Distribución Aleatoria , Resultado del Tratamiento
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