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1.
Ecotoxicol Environ Saf ; 270: 115834, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38101976

RESUMEN

In aquatic ecosystems, light penetrating the sediment surface in shallow lakes may regulate the internal phosphorus (P) release through benthic primary production, which subsequently affects oxidation, pH levels, and alkaline phosphatase activity in the upper sediment. To study the effects of light exposure on the P dynamics at the sediment-water interface under eutrophic conditions, a two-month mesocosm experiment was conducted in twelve cement tanks (1000 L each). The tanks were equipped with Light-Emitting Diode (LED) lights, and surface sediments collected from eutrophic Lake Nanhu (China) were exposed to four different light intensities (0, 50, 100, 200 µmol m-2 s-1). The results revealed that: 1) Both the total phosphorus concentration and the phosphorus release flux from the sediment were lower in the light treatments (mean value, 0.59-0.71 mg L-1 and 0.00-0.01 mg m-2 d-1, respectively) than in the control treatment (0.77 mg L-1 and 0.01 mg m-2 d-1, respectively), indicating that light supplement could decrease the internal P release. 2) Benthic primary production promoted by light directly absorbed soluble reactive phosphorus and decreased the internal P release. The resulting improved production could also increase dissolved oxygen concentrations at the sediment-water interface, thus indirectly inhibiting internal P release. 3) The relative contributions of direct absorption and indirect inhibition on the internal P release ranged between 23% to 69% and 31% to 77% depending on the light intensity.


Asunto(s)
Fósforo , Contaminantes Químicos del Agua , Fósforo/análisis , Lagos , Ecosistema , Eutrofización , Sedimentos Geológicos , Agua , China , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente
2.
ACS Appl Mater Interfaces ; 15(2): 2529-2537, 2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36595474

RESUMEN

Resveratrol has been garnering considerable attention as a promising chemopreventive and chemotherapeutic drug against metastatic tumors such as triple-negative breast cancer (TNBC). However, the potential in vivo application of resveratrol has been highly limited due to its poor solubility, rapid conjugation, low bioavailability, and bioactivity. In this study, a silica mesoporous nanoparticle (MSN)-based drug delivery system (DDS), named Au-Se@MSN, is developed to deliver the loaded resveratrol, endowing it with properties of targeted delivery, excellent bioavailability, and antioxidation of resveratrol. In Au-Se@MSN(RES), gold nanoparticles functionalized with selenol-modified uPA-specific peptides act as gatekeepers to avoid the interference of glutathione in the bloodstream and realize negligible premature release of resveratrol during delivery. Au-Se@MSN(RES) shows prolonged resveratrol release at the tumor site and endows resveratrol with a remarkable in vitro therapeutic effect. The pharmacological dose of resveratrol treatment on MDA-MB-231 cells was found to result in the generation of a high level of NAD(P)H other than H2O2, indicating reductive stress instead of oxidative stress involved in the resveratrol therapeutic process. In vivo experiments showed that Au-Se@MSN greatly improves the chemotherapeutic effect of resveratrol on mice bearing TNBC tumors, and damage to normal tissues and cells is negligible. Overall, Au-Se@MSN is a potential tool for further studies on the anticancer mechanism and clinical applications of resveratrol.


Asunto(s)
Nanopartículas del Metal , Sistema de Administración de Fármacos con Nanopartículas , Resveratrol , Neoplasias de la Mama Triple Negativas , Animales , Ratones , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Oro/química , Peróxido de Hidrógeno , Nanopartículas del Metal/química , Nanopartículas/química , Péptidos/química , Porosidad , Resveratrol/farmacología , Resveratrol/uso terapéutico , Dióxido de Silicio/química , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Selenio/química , Sistema de Administración de Fármacos con Nanopartículas/farmacología , Sistema de Administración de Fármacos con Nanopartículas/uso terapéutico
3.
Front Nutr ; 10: 1270179, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38239836

RESUMEN

Background: Data regarding the association between antioxidant supplementation and incident dementia are limited. Methods: We included 494,632 adults (54.5% females) aged 40-71 years at baseline from the United Kingdom Biobank in the final analysis. Incident dementia was ascertained using hospital inpatient and death records up to January 2021. Results: Over a median follow-up of 11.9 years, 7,128 new cases of all-cause dementia, 2,772 cases of Alzheimer's disease, and 1,397 cases of vascular dementia were recorded. The hazard ratio (95% CI) for incident dementia associated with zinc supplementation was 0.84 (0.74-0.96), and the association remained significant after adjusting for all confounders (0.84 (0.74-0.96)). In the full model, zinc supplementation was associated with a reduced risk of Alzheimer's disease [HR (95% CI): 0.71 (0.57-0.88)]. There was no significant association between zinc supplementation and the risk of vascular dementia. No significant associations with incident dementia were observed for other antioxidant supplementation. The association between zinc supplementation and incident dementia was significant among individuals with [HR (95% CI): 0.34 (0.15-0.77)] and without cataract [0.87 (0.77-0.99)] but it was stronger among those with cataract (p value for interaction = 0.0271). Conclusion: Our findings suggest that zinc supplementation may help reduce the risk of all-cause dementia and Alzheimer's disease in middle-aged or older adults, especially among those with cataracts.

4.
BMC Complement Med Ther ; 22(1): 93, 2022 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-35354453

RESUMEN

BACKGROUND: Sini Decoction (SND), a classic Chinese medicine prescription, has been proved to have a good effect on heart failure (HF), whereas its underlying mechanism is still unclear. In order to explore the therapeutic mechanism of SND, we combined with 16S rRNA gene sequencing to analyze the composition of gut microflora in rats with HF. MATERIAL AND METHODS: Twenty Sprague-Dawley (SD) rats were divided into four groups (n = 5): normal group, model group, SND treatment group (SNT group), and metoprolol (Met) treatment group (Meto group). All the rats except the normal group were intraperitoneally injected with doxorubicin (concentration 2 mg/mL, dose 0.15 mL/100 g) once a week to induce HF. After successfully modeling, SND and Met were gavaged to rats, respectively. After the treatment period, blood was collected for hematological analyses, myocardial tissue and colon tissues were collected for Hematoxylin-Eosin (H&E) staining, and mucosal scrapings were collected for Illumina Miseq high-throughput sequencing. RESULTS: Echocardiographic results suggested that both left ventricular ejection fraction (LVEF) and left ventricular fraction shortening (LVFS) in Model rats decreased compared with normal rats. The results of H&E staining showed that compared with the model group, the structures of myocardial tissue and colon tissue in the SNT group and Meto group showed a recovery trend. Alpha results showed that the model group had higher species diversity and richness compared with the normal group. After treatment, the richness and diversity of intestinal bacteria in the SNT group were significantly restored, and Met also showed the effect of adjusting bacterial diversity, but its effect on bacterial richness was not ideal. At the Family level, we found that the number of several bacteria associated with HF in the model group increased significantly. Excitingly, SND and Met had shown positive effects in restoring these HF-associated bacteria. Similarly, the results of Linear discriminant analysis (LDA) showed that both SND and Met could reduce the accumulation of bacteria in the model group caused by HF. CONCLUSION: Collectively, SND can improve HF by regulating the intestinal flora. This will provide new ideas for the clinical treatment of patients with HF.


Asunto(s)
Insuficiencia Cardíaca , Función Ventricular Izquierda , Animales , Bacterias , Medicamentos Herbarios Chinos , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Mucosa Intestinal , ARN Ribosómico 16S , Ratas , Ratas Sprague-Dawley , Volumen Sistólico
5.
Food Funct ; 13(1): 121-130, 2022 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-34897342

RESUMEN

Mogroside-rich extract (MGE), the main bioactive component of dried Siraitia grosvenorii fruit, has long been used as a natural sweetener and traditional Chinese medicine. This extract possesses various types of pharmacological activities, such as anti-inflammatory, antioxidative, hypoglycemic and hypolipemic activities. Moreover, we recently revealed that MGE has beneficial effects on female reproduction. Increasing maternal age leads to a rapid reduction in female fertility; in particular, it dramatically decreases ovarian function. Nevertheless, whether MGE can alleviate ovarian aging and the underlying mechanisms have not yet been explored. In this study, mice were treated with MGE by supplementation in drinking water from 10 to 44 weeks of age. Then, ovarian function and molecular changes were determined. Our findings showed that MGE treatment protected aged mice from estrous cycle disorder. Moreover, MGE treatment significantly increased the ovarian reserves of aged mice. RNA-seq data showed that MGE upregulated the expression of genes related to gonad development, follicular development, and hormone secretion in ovarian tissue. Additionally, inflammatory stress was induced, as indicated by upregulation of inflammation-related gene expression and elevated TNF-α levels in the ovarian tissues of aged mice; however, MGE treatment attenuated inflammatory stress. In summary, our findings demonstrate that MGE can ameliorate age-related estrous cycle disorder and ovarian reserve decline in mice, possibly by alleviating ovarian inflammatory stress.


Asunto(s)
Antiinflamatorios , Cucurbitaceae/química , Reserva Ovárica/efectos de los fármacos , Extractos Vegetales , Triterpenos , Envejecimiento/efectos de los fármacos , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Femenino , Inflamación/metabolismo , Ratones , Extractos Vegetales/química , Extractos Vegetales/farmacología , Estrés Fisiológico/efectos de los fármacos , Triterpenos/química , Triterpenos/farmacología
6.
Ecotoxicol Environ Saf ; 217: 112244, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33933891

RESUMEN

Nickel is widely spread by different anthropogenic activities and shows toxicity for plant growth and development. Whether rhizobia symbiotically fix nitrogen can eliminate or reduce nickel toxic effect on plant or not is still unknown. This study was aimed to investigate the effect of different rhizobia genus inoculation on growth, nitrogen fixing ability, metal accumulation and enzymatic antioxidative balance of Pongamia pinnnaa. Inoculation with Rhizobium pisi and Ochrobacterium pseudogrignonense increased the all the growth parameters both in 0 and 40 mg/kg nickel as comparison with control. Only shoot length increased in presence of nitrogen as compared with no supply of nitrogen. Nitrogen content also increased both in rhizobia inoculation as compared to no nitrogen supply and non-inoculation control, respectively. Nickel uptake was higher in shoots and leaves but lower in roots in case of inoculation as compared to non-inoculation control. Rhizobia inoculation improved the plant antioxidant capacity by increasing the activity of enzymatic scavengers catalase (CAT), superoxide dismutase (SOD), peroxidase (POD) and ascorbate (GR). However, 40 mg/kg of nickel adding showed mostly effect on the activity CAT, SOD, POD in leaves. All the enzymatic activity showed a significant increase in absence of nitrogen supply as compared nitrogen supply. Our results suggested that rhizobia inoculation effectively mediated nickel stress for legume plants by increasing nitrogen supplement and inducing antioxidant capacity.


Asunto(s)
Brucellaceae/fisiología , Millettia/fisiología , Níquel/metabolismo , Rhizobium/fisiología , Antioxidantes , Ácido Ascórbico , Catalasa/metabolismo , Millettia/metabolismo , Nitrógeno , Oxidación-Reducción , Raíces de Plantas/metabolismo , Superóxido Dismutasa/metabolismo , Simbiosis
7.
Biomed Chromatogr ; 34(8): e4865, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32330321

RESUMEN

The aerial parts of Dracocephalum moldavica L. are extensively used in traditional ethnic medicines in China as a remedy for cardiovascular and cerebrovascular damage. However, the chemical composition and the accumulation of main secondary metabolites of D. moldavica in different natural environments remain unclear. This study aimed to conduct a qualitative and quantitative analysis of the main secondary metabolites to explore the quality variation of D. moldavica in markets. The evaluation of space-time accumulation of main secondary metabolites in D. moldavica was carried out during different growth periods and in different geographical locations. A total of 35 ingredients were detected and 24 identified, including 21 flavonoids, two phenolic acids and one coumarin by UPLC-QTOF-MS method. Furthermore, a simple and convenient HPLC method was successfully developed for the simultaneous determination of lutelin-7-O-glucuronide and tilianin and rosmarinic acid in D. moldavica. The results of space-time accumulation analysis showed the distinct variation of secondary metabolites of D. moldavica with the growth period and geographical location. Finally, the current study provided a meaningful and useful approach for comprehensively evaluating the quality of D. moldavica.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Lamiaceae/química , Lamiaceae/metabolismo , Espectrometría de Masas/métodos , Fitoquímicos/análisis , Cumarinas/análisis , Cumarinas/química , Cumarinas/metabolismo , Hidroxibenzoatos/análisis , Hidroxibenzoatos/química , Hidroxibenzoatos/metabolismo , Límite de Detección , Modelos Lineales , Fitoquímicos/química , Fitoquímicos/metabolismo , Extractos Vegetales/química , Estructuras de las Plantas/química , Estructuras de las Plantas/metabolismo , Reproducibilidad de los Resultados
8.
Sci Total Environ ; 690: 321-328, 2019 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-31299567

RESUMEN

Cadmium (Cd)-contaminated paddy soil has become a global agricultural safety issue. The application of foliage dressing with mineral elements to alleviate Cd toxicity in rice might offer a cost-effective and practical strategy for safe food production. In this study, a pot experiment was conducted to optimize foliar composition and dosage. Field experiments in two consecutive rice seasons were performed to investigate the effectiveness and mechanisms of foliage dressing. Foliar spray of S, P, and a mixture of both were effective to reduce the Cd concentration in rice grain. The maximum decrease by leaf-grain translocation was achieved at 84%, and the maximum decrease of bio-concentration was 69% in the stem. The reduction of Cd concentration in rice decreased the direct damage to the photosynthetic system, and then increased the rice growth. Foliage dressing relieved the oxidative stress of Cd to rice by decreasing the MDA content, and increasing antioxidant enzyme activities. Foliar spray with S likely reduced Cd accumulation in rice by minimizing the production of reactive oxygen species, improving the activities of enzymatic and non-enzymatic antioxidant defense systems, and manipulating glutathione synthesis. The detoxification of foliar spray with P was originated from the decrease of Cd translocation and maintaining photosynthetic machinery. These results indicated that foliage dressing with S and P has great potential for the remediation of vast agricultural fields.


Asunto(s)
Cadmio/química , Oryza/química , Agricultura/métodos , Restauración y Remediación Ambiental/métodos , Fósforo/química , Suelo , Contaminantes del Suelo , Azufre/química
9.
Otol Neurotol ; 40(5): e542-e547, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31083094

RESUMEN

OBJECTIVE: To compare the influence of visual distractors on the performance of auditory selective attention between prelingually deaf children with a CI (cochlear implant) and children with normal-hearing. DESIGN: Twenty-two patients who had a cochlear implant device (10 males and 12 females, aged 6.64 ±â€Š0.99 yrs) and 16 normal-hearing children (6 males and 10 females, aged 6.09 ±â€Š0.51 yrs) were recruited. Half of the auditory stimuli were presented together with visual stimuli, and participants were required to complete an auditory identification task. Reaction times and discriminability (d') for these two groups were recorded and calculated. RESULTS: The normal-hearing group had shorter mean reaction times than the CI group in detecting auditory targets. With visual distraction, the d' of the normal-hearing group was significantly better than that of CI group (t = 2.649, p = 0.012), while no statistical significance was found between the two groups without visual distraction (t = 0.693, p = 0.493). CONCLUSION: Enhanced processing of visual stimuli interferes with auditory perception in CI users by occupying the capacity-limited attention.


Asunto(s)
Atención , Percepción Auditiva , Implantes Cocleares , Sordera/psicología , Sordera/terapia , Estimulación Luminosa , Estimulación Acústica , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Pruebas Auditivas , Humanos , Masculino , Tiempo de Reacción
10.
Int J Pediatr Otorhinolaryngol ; 99: 85-89, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28688572

RESUMEN

OBJECTIVE: Visual take-over of the auditory cortex in prelingual deaf children has been widely reported. However, there have been few studies on visual cortex plasticity after cochlear implantation (CI). In this study, we investigated the hypothesis that extrinsic auditory stimulation following CI in prelingual deafened children can induce visual cortex plasticity. METHOD: Visual evoked potentials (VEPs) were recorded in 37 CI children (4 groups with different use times) and 8 control subjects, in response to sound and nonsound stimuli. Latency and amplitude were analyzed for the P1, N1 and P2 components on the Oz electrode. Comparisons of VEP were conducted between the sound and nonsound stimuli and among different groups in order to view evidence of visual cortex reorganization. RESULTS: The latency of the P2 component was significantly longer at the occipital site (Oz) in CI 0M than those in the other four groups. After the effect of age was excluded, a significant negative correlation was found between CI usage and P2 latency of nonsound stimuli. Occipital P1N1 latency and P1 amplitude were not affected by group or stimulus category. However, the N1 and P2 amplitudes were significantly larger in response to a sound stimulus than to a nonsound stimulus. CONCLUSION: Our findings suggest that P2 latency develops with CI usage and may be a biomarker of visual cortex plasticity.


Asunto(s)
Implantación Coclear/métodos , Sordera/cirugía , Potenciales Evocados Visuales/fisiología , Corteza Visual/fisiopatología , Estimulación Acústica/métodos , Corteza Auditiva/fisiopatología , Niño , Preescolar , Implantes Cocleares , Electroencefalografía , Potenciales Evocados Auditivos/fisiología , Femenino , Humanos , Masculino
11.
Otol Neurotol ; 38(8): 1104-1111, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28727651

RESUMEN

OBJECTIVE: Although visual processing recruitment of the auditory cortices has been reported previously in prelingually deaf children who have a rapidly developing brain and no auditory processing, the visual processing recruitment of auditory cortices might be different in processing different visual stimuli and may affect cochlear implant (CI) outcomes. METHODS: Ten prelingually deaf children, 4 to 6 years old, were recruited for the study. Twenty prelingually deaf subjects, 4 to 6 years old with CIs for 1 year, were also recruited; 10 with well-performing CIs, 10 with poorly performing CIs. Ten age and sex-matched normal-hearing children were recruited as controls. Visual ("sound" photo [photograph with imaginative sound] and "nonsound" photo [photograph without imaginative sound]) evoked potentials were measured in all subjects. P1 at Oz and N1 at the bilateral temporal-frontal areas (FC3 and FC4) were compared. RESULTS: N1 amplitudes were strongest in the deaf children, followed by those with poorly performing CIs, controls and those with well-performing CIs. There was no significant difference between controls and those with well-performing CIs. "Sound" photo stimuli evoked a stronger N1 than "nonsound" photo stimuli. Further analysis showed that only at FC4 in deaf subjects and those with poorly performing CIs were the N1 responses to "sound" photo stimuli stronger than those to "nonsound" photo stimuli. No significant difference was found for the FC3 and FC4 areas. No significant difference was found in N1 latencies and P1 amplitudes or latencies. CONCLUSION: The results indicate enhanced visual recruitment of the auditory cortices in prelingually deaf children. Additionally, the decrement in visual recruitment of auditory cortices was related to good CI outcomes.


Asunto(s)
Corteza Auditiva , Implantes Cocleares , Sordera/fisiopatología , Percepción Visual/fisiología , Estimulación Acústica , Corteza Auditiva/fisiología , Niño , Implantación Coclear/métodos , Sordera/cirugía , Femenino , Humanos , Masculino , Personas con Deficiencia Auditiva , Estimulación Luminosa
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