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1.
J Cancer Surviv ; 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38970716

RESUMEN

PURPOSE: To investigate the potential impact of concurrent aerobic and strength training (CT) on women diagnosed with breast cancer. METHODS: Articles published in English and indexed in the PubMed, Web of Science, SPORTDiscus, The Cochrane Library, PsycINFO, EMBASE, and CINAHL Plus databases from their inception to 12 December 2023 were searched. Eligible studies were randomized controlled trials that involved CT and assessed cardiorespiratory fitness, cancer-related fatigue, and quality of life (QoL) using specialized tools. Subgroup analyses were conducted as per treatment status and characteristics. Risk of bias was evaluated with the Cochrane risk-of-bias tool (RoB 2.0). RESULTS: This study included 29 studies involving 2071 participants. CT was found to significantly improve patients' cardiorespiratory fitness (weighted mean difference = 4.24 mL/kg/min, 95% confidence interval (CI) = 1.93-6.55, P < 0.001), cancer-related fatigue (standardized mean difference (SMD) = - 0.74, 95% CI = - 1.05 to - 0.44, P < 0.001), and QoL (SMD = 0.76, 95% CI = 0.50-1.01, P < 0.001). The analysis of secondary outcomes found that CT could significantly improve patients' body composition, anxiety, pain, sleep disorders, and anorexia and enhance upper and lower limb muscle strength, but was ineffective on depression. CONCLUSION: For women with breast cancer, CT significantly enhances cardiorespiratory fitness, alleviates cancer-related fatigue, and improves QoL. The health benefits of CT are inferior in the postmenopausal cohort compared to the overall study population. IMPLICATIONS FOR CANCER SURVIVORS: CT is advisable for female breast cancer survivors due to its significant effectiveness in mitigating cancer-related fatigue, enhancing cardiorespiratory fitness, and improving the QoL.

2.
BMC Public Health ; 24(1): 1816, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38977980

RESUMEN

BACKGROUND: Exercise has been identified as a promising non-pharmacological therapy for the management of depression, but there is still controversy over which type is most effective. We aimed to compare and rank the types of exercise that improve depression in postmenopausal women by quantifying information from randomized controlled trials (RCTs). METHODS: The PubMed, Web of Science, SPORTDiscus, CNKI, The Cochrane Library, PsycINFO, EMBASE, and CINAHL Plus databases were searched to identify articles published from inception to 1 March 2024 reporting RCTs that examined the effectiveness of exercise on depression in postmenopausal women. The risk of bias was assessed using the revised Cochrane risk-of-bias tool for RCTs. The quality of the evidence for each comparison was graded using the online confidence in network meta-analysis tool (CINeMA). Standardized mean differences (SMDs) were calculated using the mean and standard deviation of pre-to-post intervention changes and then pooled using a random effects model in a pairwise meta-analysis using Review Manager 5.4. Then, a frequentist network meta-analysis was conducted using a random effects model was conducted to evaluate the efficacy of different exercise types using the network package of Stata 15. RESULTS: This study included 26 studies involving 2,170 participants. The pairwise meta-analysis revealed that exercise had a significant positive effect on depression in postmenopausal women (SMD = -0.71, 95% confidence interval [CI] = -0.94 to -0.48; I2 = 78%). The network meta-analysis revealed that mind-body exercise (SMD = -0.97, 95% CI = -1.28 to -0.67), aerobic exercise (SMD = -0.58, 95% CI = -0.88 to -0.27) and multicomponent exercise (SMD = -0.57, 95% CI = -1.15 to -0.002) significantly reduced depression compared to the control intervention. Mind-body exercise had the highest probability of being the most effective intervention. Exercise interventions also showed positive effects on anxiety. Most studies were judged to have some concerns regarding their risk of bias, and the confidence in evidence was often very low according to CINeMA. CONCLUSION: For postmenopausal women, there is very low to moderate quality evidence that exercise interventions are an effective antidepressant therapy, with mind-body exercise most likely being the optimal type. TRIAL REGISTRATION: This meta-analysis was prospectively registered with PROSPERO (registration number: CRD42024505425).


Asunto(s)
Depresión , Metaanálisis en Red , Posmenopausia , Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Posmenopausia/psicología , Femenino , Depresión/terapia , Ansiedad/terapia , Terapia por Ejercicio/métodos , Ejercicio Físico/psicología , Persona de Mediana Edad
3.
Toxics ; 12(7)2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-39058123

RESUMEN

In this study examining the effects of temperature and dissolved oxygen (DO) on arsenic (As) release at the sediment-water interface (SWI), it was found that an increase in temperature promoted the formation of an anaerobic environment and the reduction and desorption of As fractions within the sediments. A temperature of 32 °C was the most favorable condition for As release at the SWI, and low DO conditions aggravated this process. Even under high DO conditions, the release of sediment As was significantly accelerated under high-temperature conditions, allowing dissolved As to rapidly migrate to the overlying water. In this process, the release of As from sediments was a consequence of the transformation of As fractions in the sediments.

4.
Psychooncology ; 33(7): e6370, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38937093

RESUMEN

OBJECTIVE: To compare and rank the effectiveness of four primary categories of exercise modalities (aerobic, resistance, mind-body, and combined exercise [CE]) in improving the Quality of life (QoL) of women with breast cancer in a network meta-analysis (NMA). METHODS: Articles published in English and indexed in the PubMed (MEDLINE), EBSCO, Web of Science, SPORTDiscus, The Cochrane Library, Google Scholar, PsycINFO, EMBASE, and CINAHL Plus databases were identified from inception to 12 October 2023. Studies that met the eligibility criteria were assessed for risk of bias. A frequentist NMA was conducted to appraise the efficacy of different exercise types. RESULTS: This study included 56 studies with 3904 participants. Aerobic, mind-body, and combined exercises effectively improved QoL compared to controls. The surface under the cumulative ranking curve (SUCRA) indicated that CE best improved patients' QoL (SUCRA = 96.7%). Analysis of the secondary outcomes suggests that exercise reduced patients' depression (standardized mean difference [SMD] = -0.38, 95% confidence interval [CI] = -0.70 to -0.06, p < 0.001; I2 = 79%) and anxiety (SMD = -0.50, 95% CI = -0.69 to -0.31, p < 0.001; I2 = 27.4%) but did not affect self-esteem. CONCLUSION: All exercise types but resistance were effective in improving the QoL of women with breast cancer, CE (the combination of aerobic and resistance exercise) had the highest likelihood of being optimal for improving QoL.


Asunto(s)
Ansiedad , Neoplasias de la Mama , Terapia por Ejercicio , Metaanálisis en Red , Calidad de Vida , Humanos , Calidad de Vida/psicología , Neoplasias de la Mama/psicología , Neoplasias de la Mama/terapia , Femenino , Terapia por Ejercicio/métodos , Ansiedad/psicología , Depresión/psicología , Ejercicio Físico/psicología
5.
Aquat Toxicol ; 270: 106905, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38569307

RESUMEN

The enhanced adsorption of pollutants on biofilm-developed microplastics has been proved in many studies, but the ecotoxicological effects of biofilm-developed microplastics on organisms are still unclear. In this study, adult zebrafish were exposed to original microplastics, biofilm-developed microplastics, original microplastics absorbed with oxytetracycline (OTC), and biofilm-developed microplastics absorbed with OTC for 30 days. The intestinal histological damage, intestinal biomarker response, gut microbiome and antibiotic resistance genes (ARGs) profile of zebrafish were measured to explore the roles of biofilm in the effects of microplastics. The results showed that biofilm-developed microplastics significantly increased the number of goblet cells in intestinal epithelium compared with the control group. The biofilm-developed microplastics also induced the oxidative response in the zebrafish intestines, and biofilm changed the response mode in the combined treatment with OTC. Additionally, the biofilm-developed microplastics caused intestinal microbiome dysbiosis, and induced the abundance of some pathogenic genera increasing by several times compared with the control group and the original microplastics treatments, regardless of OTC adsorption. Furthermore, the abundance of ARGs in biofilm-developed microplastics increased significantly compared with the control and the original microplastic treatments. This study emphasized the significant influence and unique role of biofilm in microplastic studies.


Asunto(s)
Oxitetraciclina , Contaminantes Químicos del Agua , Animales , Oxitetraciclina/toxicidad , Microplásticos/toxicidad , Plásticos , Pez Cebra , Contaminantes Químicos del Agua/toxicidad , Antibacterianos/toxicidad , Intestinos
6.
Front Endocrinol (Lausanne) ; 15: 1319827, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38510704

RESUMEN

Osteoarthritis (OA) is a common degenerative joint disease that can affect almost any joint, mainly resulting in joint dysfunction and pain. Worldwide, OA affects more than 240 million people and is one of the leading causes of activity limitation in adults. However, the pathogenesis of OA remains elusive, resulting in the lack of well-established clinical treatment strategies. Recently, energy metabolism alterations have provided new insights into the pathogenesis of OA. Accumulating evidence indicates that glucose metabolism plays a key role in maintaining cartilage homeostasis. Disorders of glucose metabolism can lead to chondrocyte hypertrophy and extracellular matrix degradation, and promote the occurrence and development of OA. This article systematically summarizes the regulatory effects of different enzymes and factors related to glucose metabolism in OA, as well as the mechanism and potential of various substances in the treatment of OA by affecting glucose metabolism. This provides a theoretical basis for a better understanding of the mechanism of OA progression and the development of optimal prevention and treatment strategies.


Asunto(s)
Cartílago Articular , Osteoartritis , Adulto , Humanos , Condrocitos , Osteoartritis/etiología , Osteoartritis/terapia , Cartílago Articular/patología , Dolor/metabolismo , Glucosa/metabolismo
7.
Int J Mol Sci ; 25(5)2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38473715

RESUMEN

In female mammals, the proliferation and apoptosis of granulosa cells (GCs) have been shown to determine the fate of follicles. DNA methyltransferases (DNMTs) and SLCO3A1 have been reported to be involved in the survival of GCs and follicular growth. However, the molecular mechanisms enabling DNMTs to regulate the expression of SLCO3A1 to participate in follicular growth are unclear. In this study, we found that the knockdown of DNMT1 enhanced the mRNA and protein levels of SLCO3A1 by regulating the chromatin accessibility probably. Moreover, SLCO3A1 upregulated the mRNA and protein levels of MCL1, PCNA, and STAR to promote the proliferation of GCs and facilitated cell cycle progression by increasing the mRNA and protein levels of CCNE1, CDK2, and CCND1, but it decreased apoptosis by downregulating the mRNA and protein levels of CASP3 and CASP8. Moreover, SLCO3A1 promoted the growth of porcine follicles and development of mice follicles. In conclusion, the knockdown of DNMT1 upregulated the mRNA and protein levels of SLCO3A1, thereby promoting the proliferation of GCs to facilitate the growth and development of ovarian follicles, and these results provide new insights into investigations of female reproductive diseases.


Asunto(s)
Células de la Granulosa , Folículo Ovárico , Ratones , Femenino , Porcinos , Animales , Células de la Granulosa/metabolismo , Folículo Ovárico/metabolismo , Proliferación Celular/genética , Mamíferos/genética , ARN Mensajero/genética
8.
Toxics ; 11(11)2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37999542

RESUMEN

The pH and dissolved oxygen (DO) conditions are important environmental factors that control the migration of arsenic (As) at the sediment-water interface. This study investigates the distribution differences of reactive iron, manganese, and arsenic at the sediment-water interface under anaerobic and aerobic conditions at different pH levels. The strong buffering capacity of sediment to water pH results in a shift towards neutral pH values in the overlying water under different initial pH conditions. The level of DO becomes a key factor in the release of As from sediment, with lower DO environments exhibiting higher release quantities and rates of As compared to high DO environments. Under low DO conditions, the combined effects of ion exchange and anaerobic reduction lead to the most significant release of As, particularly under pH 9.5 conditions. The formation of amorphous ferrous sulfide compounds under low DO conditions is a significant factor contributing to increased arsenic concentration in the interstitial water. Therefore, the re-migration of endogenous arsenic in shallow lake sediments should consider the combined effects of multiple driving forces.

9.
Front Pharmacol ; 14: 1218059, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37601070

RESUMEN

As the outbreak of COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) first broke out in Hubei Province, China, at the end of 2019. It has brought great challenges and harms to global public health. SARS-CoV-2 mainly affects the lungs and is mainly manifested as pulmonary disease. However, one of the biggest crises arises from the emergence of COVID-19-induced fibrosis. At present, there are still many questions about how COVID-19 induced pulmonary fibrosis (PF) occurs and how to treat and regulate its long-term effects. In addition, as an important process of fibrosis, the effect of COVID-19 on epithelial-mesenchymal transition (EMT) may be an important factor driving PF. This review summarizes the main pathogenesis and treatment mechanisms of COVID-19 related to PF. Starting with the basic mechanisms of PF, such as EMT, transforming growth factor-ß (TGF-ß), fibroblasts and myofibroblasts, inflammation, macrophages, innate lymphoid cells, matrix metalloproteinases and tissue inhibitors of metalloproteinases, hedgehog pathway as well as Notch signaling. Further, we highlight the importance of COVID-19-induced EMT in the process of PF and provide an overview of the related molecular mechanisms, which will facilitate future research to propose new clinical therapeutic solutions for the treatment of COVID-19-induced PF.

10.
Front Neurol ; 14: 1125172, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37139055

RESUMEN

Background: This study aimed to observe the effects of six different types of AI rehabilitation techniques (RR, IR, RT, RT + VR, VR and BCI) on upper limb shoulder-elbow and wrist motor function, overall upper limb function (grip, grasp, pinch and gross motor) and daily living ability in subjects with stroke. Direct and indirect comparisons were drawn to conclude which AI rehabilitation techniques were most effective in improving the above functions. Methods: From establishment to 5 September 2022, we systematically searched PubMed, EMBASE, the Cochrane Library, Web of Science, CNKI, VIP and Wanfang. Only randomized controlled trials (RCTs) that met the inclusion criteria were included. The risk of bias in studies was evaluated using the Cochrane Collaborative Risk of Bias Assessment Tool. A cumulative ranking analysis by SUCRA was performed to compare the effectiveness of different AI rehabilitation techniques for patients with stroke and upper limb dysfunction. Results: We included 101 publications involving 4,702 subjects. According to the results of the SUCRA curves, RT + VR (SUCRA = 84.8%, 74.1%, 99.6%) was most effective in improving FMA-UE-Distal, FMA-UE-Proximal and ARAT function for subjects with upper limb dysfunction and stroke, respectively. IR (SUCRA = 70.5%) ranked highest in improving FMA-UE-Total with upper limb motor function amongst subjects with stroke. The BCI (SUCRA = 73.6%) also had the most significant advantage in improving their MBI daily living ability. Conclusions: The network meta-analysis (NMA) results and SUCRA rankings suggest RT + VR appears to have a greater advantage compared with other interventions in improving upper limb motor function amongst subjects with stroke in FMA-UE-Proximal and FMA-UE-Distal and ARAT. Similarly, IR had shown the most significant advantage over other interventions in improving the FMA-UE-Total upper limb motor function score of subjects with stroke. The BCI also had the most significant advantage in improving their MBI daily living ability. Future studies should consider and report on key patient characteristics, such as stroke severity, degree of upper limb impairment, and treatment intensity/frequency and duration. Systematic review registration: www.crd.york.ac.uk/prospero/#recordDetail, identifier: CRD42022337776.

11.
ACS Appl Mater Interfaces ; 15(16): 20100-20109, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37058142

RESUMEN

A heterogeneous interface usually plays a versatile role in modulating catalysis and the durability of hybrid electrocatalysts for oxygen evolution reaction (OER), and its intrinsic mechanism is still in dispute due to an uncertain correlation of initial, intermediate and active phases. In this article, the CoMoO4·0.69H2O/Co3O4 heterogeneous interface is configured to understand the evolution kinetics of these correlated phases. Due to the chemically and electrochemically "inert" character of Co3O4 support, lattice strain with 3.31% tuning magnitude in primary CoMoO4·0.69H2O can be inherited after spontaneous dissolution of molybdenum cations in electrolyte, dominating catalytic activity of the reconstructed CoOOH. In situ Raman spectroscopy demonstrates reversible conversion between active CoOOH and amorphous cobalt oxide during OER when positive and negative potentials are sequentially supplied onto hybrid catalysts with favorable strain. Therefore, superior durability with negligible decay after 10 cycles is experimentally identified for intermittent oxygen evolution. Theoretical calculations indicate that appropriate stress within the electrocatalyst could reduce the reaction energy barrier and enhance the OER performance by optimizing the adsorption of intermediates.

12.
Rev Cardiovasc Med ; 24(8): 237, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39076695

RESUMEN

Background: Valvular heart disease (VHD) is a type of cardiovascular disease with abnormal heart valve structure and/or function and a rapidly growing cause of global cardiovascular morbidity and mortality. Physical inactivity is a problem for patients with VHD, especially after surgery. However, there is no data on the effects of exercise on VHD from large multicentre randomised controlled trials (RCTs). Therefore, we conducted a systematic review and meta-analysis to provide a comprehensive analysis of small RCTs to evaluate the effects of exercise on cardiopulmonary function in patients with VHD and provide an evidence-based medicine basis for developing and guiding the clinical application of exercise in patients with VHD. Methods: We conducted a systematic review and meta-analysis of RCTs. We systematically searched electronic databases (PubMed, Web of Science, Embase, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure [CNKI], China Science and Technology Journal Database [VIP], WanFang Database, and SinoMed [CBM]) for all studies on exercise and VHD from their inception to January 2023. The quality of included studies was assessed using the Cochrane risk-of-bias tool. The primary outcomes were the six-minute walk test distance (6MWD), left ventricular ejection fraction (LVEF), and short-form 36-item health survey (SF-36). Results: This systematic review included 22 RCTs with 1520 subjects (869 men and 651 women). The meta-analysis results showed that exercise significantly improved exercise capacity measured by the 6MWD (mean difference [MD] = 25.54, 95% confidence interval [CI] = 19.98-31.11, I 2 = 0%, p < 0.00001), LVEF (MD = 6.20, 95% CI = 4.76-7.65, I 2 = 66%, p < 0.00001), and quality of life measured by the SF-36 (physical function: MD = 3.42, 95% CI = 2.12-4.72, I 2 = 12%, p < 0.00001; mental health: MD = 3.86, 95% CI = 0.52-7.20, I 2 = 68%, p = 0.020; social function: MD = 2.30, 95% CI = 0.64-3.97, I 2 = 45%, p = 0.007; bodily pain: MD = 2.60, 95% CI = 0.83-4.37, I 2 = 22%, p = 0.004) in patients with VHD compared to healthy controls. Conclusions: This study suggests that exercise can significantly improve cardiopulmonary function, enhance physical and social function, reduce bodily pain, and potentially improve mental health in patients with VHD, providing an evidence-based basis for better recovery in patients with VHD.

13.
J Environ Sci (China) ; 90: 244-252, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32081320

RESUMEN

Hydrilla verticillata (waterthyme) has been successfully used for phytoremediation in arsenic (As) contaminated water. To evaluate the effects of environmental factors on phytoremediation, this study conducted a series of orthogonal design experiments to determine optimal conditions, including phosphorus (P), nitrogen (N), and arsenate (As(V)) concentrations and initial pH levels, for As accumulation and biotransformation using this aquatic plant species, while also analyzing As species transformation in culture media after 96-hr exposure. Analysis of variance and the signal-to-noise ratio were used to identify both the effects of these environmental factors and their optimal conditions for this purpose. Results indicated that both N and P significantly impacted accumulation, and N was essential in As species transformation. High N and intermediate P levels were critical to As accumulation and biotransformation by H. verticillata, while high N and low P levels were beneficial to As species transformation in culture media. The highest total arsenic accumulation was (197.2 ± 17.4) µg/g dry weight when As(V) was at level 3 (375 µg/L), N at level 2 (4 mg/L), P at level 1 (0.02 mg/L), and pH at level 2 (7). Although H. verticillata is highly efficient in removing As(V) from aquatic environments, its use could be potentially harmful to both humans and the natural environment due to its release of highly toxic arsenite. For cost-effective and ecofriendly phytoremediation of As-contaminated water, both N and P are helpful in regulating As accumulation and transformation in plants.


Asunto(s)
Arsénico/metabolismo , Hydrocharitaceae/metabolismo , Contaminantes Químicos del Agua/metabolismo , Biodegradación Ambiental , Biotransformación
14.
Ultrasound Med Biol ; 46(1): 1-10, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31575429

RESUMEN

The aim of the work described here was to investigate the value of point-of-care ultrasound (POCUS) in the early assessment of the severity of pulmonary edema in rabbits. A rabbit oleic acid (OA)-induced pulmonary edema model was used. Thirty-two New Zealand rabbits were randomly divided into four groups: a control group and three pulmonary edema groups (mild, moderate and severe). Features of transthoracic B-line artifacts (BLA), blood pH, PaO2 and PaCO2, serum inflammatory factors, lung coefficient (LC), lung wet-to-dry weight ratio (W/D) and lung histopathology were assessed. BLA features and severity of pulmonary edema were semiquantitatively scored. Correlations between the number of BLA and PaO2, PaCO2, serum inflammatory factors, LC and W/D were analyzed. An additional 8 rabbits with severe pulmonary edema were used as the verified group, in which the lung was divided into ex vivo BLA (BLA-ev)-free (BLA-ev-free) and BLA-ev-clustered subregions depending on the features of BLA-ev recorded by ex vivo lung ultrasound. Lung specimens from each subregion were collected for histopathological examination. Relationships between features of BLA-ev and lung histopathological abnormalities were analyzed. With increasing doses of OA, number of BLA, W/D and levels of serum inflammatory factors decreased. Meanwhile, lung pathologic abnormalities were aggravated. In addition, time of appearance of BLA, blood pH and PaO2, and PaCO2 decreased dose dependently on OA (p < 0.05). Number of BLA was linear positively correlated with severity of pulmonary edema (r = 0.953, p < 0.05). Consistently, the features of BLA-ev reflected the severity of lung histopathological abnormalities (r = 0.936, p < 0.05). Thus, POCUS is useful in the early quantitative assessment of the severity of pulmonary edema.


Asunto(s)
Pruebas en el Punto de Atención , Edema Pulmonar/diagnóstico por imagen , Animales , Modelos Animales de Enfermedad , Diagnóstico Precoz , Conejos , Distribución Aleatoria , Índice de Severidad de la Enfermedad , Ultrasonografía
15.
Chemosphere ; 219: 1014-1023, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30682758

RESUMEN

Algal blooms decay affects the mobility, bioavailability, and toxicity of arsenic (As) in aquatic environments. The decaying process alters aquatic redox conditions and also introduces ample organic matter, conditions favorable for microbial reduction to simulate As release and As species transformation. This study investigated the role of algae (Microcystis aeruginosa (MA)) blooms decay on the dynamics of labile As and elements associated with its release, such as iron (Fe), manganese (Mn) and sulfide (S), at the sediment-water surface (SWI) of a shallow lake (Lake Taihu) in China, applying mesocosm incubation. A combined AgI/ZrO-Chelex diffusive gradients in thin films (DGT) technology was used to examine labile As, Fe, Mn, and S variations in sediments during none-MA, low-MA, and high-MA treatments. High-MA blooms decay generated strong anoxic conditions, which are favorable for the release of labile As, Fe, Mn, and S from sediment. Labile S produced from the reduction of sulfate caused by decaying MA was likely removed by labile Fe through the formation of Fe-sulfides under reducing conditions. Furthermore, this condition facilitated arsenate (As(V)) reduction to arsenite (As(III)), which was weakly adsorbed by Fe-sulfides and thus mobilized to the aqueous phase. An increase in the sediment resupply of solids As to pore water along with MA blooms decay was also revealed by the DGT-induced fluxes in sediment model, coupled with the average desorption rate constant increasing from 0.27 × 10-6 s-1 to 3.41 × 10-6 s-1, and the average response time decreasing from 7859 s to 1538 s.


Asunto(s)
Arsénico/análisis , Eutrofización , China , Sedimentos Geológicos/química , Hierro , Lagos/química , Metales Pesados/análisis , Sulfuros , Contaminantes Químicos del Agua/análisis
16.
Aquat Toxicol ; 198: 231-239, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29558708

RESUMEN

Increasing concern has been focused on the potential risks associated with the trophic transfer to aquatic organisms of ambient contaminants in the presence of titanium dioxide nanoparticles (nano-TiO2). This study investigated the influence of nano-TiO2 on the trophic transfer of arsenic (As) from the microalgae Nannochloropsis maritima to the brine shrimp Artemia salina nauplii. We found that nano-TiO2 could significantly facilitate As sorption on N. maritima within an exposure period of 24 h, and this sorption subsequently led to higher As trophic transfer from the algae to A. salina according to trophic transfer factors (TTFAs+nano-TiO2 > TTFAs). However, after 48 h of depuration, the retention of As in A. salina fed As-nano-TiO2-contaminated algae was even lower than that in A. salina fed As-contaminated algae at the same exposure concentrations. This result indicates that the increased food chain transfer of As in the presence of nano-TiO2 can be explained by adsorption of As onto nano-TiO2 in contaminated food (algae), but the bioavailability of As in A. salina is reduced after the introduction of nanoparticles. Although the stress enzyme activities of superoxide dismutase (SOD) and acetylcholinesterase (AChE) in A. salina at a lower As concentration treatment in the presence of nano-TiO2 were not significantly changed, they increased with higher exposure concentrations of As with or without nano-TiO2. Our study highlighted the complex role of nanomaterials in the transfer of ambient contaminants via trophic chains and the potential of nano-TiO2 to reduce the bioavailability of As via trophic transfer to saltwater zooplankton.


Asunto(s)
Arsénico/metabolismo , Artemia/metabolismo , Cadena Alimentaria , Nanopartículas/toxicidad , Estramenopilos/metabolismo , Titanio/toxicidad , Acetilcolinesterasa/metabolismo , Adsorción , Animales , Artemia/efectos de los fármacos , Catalasa/metabolismo , Dieta , Cinética , Microalgas/efectos de los fármacos , Microalgas/metabolismo , Nanopartículas/ultraestructura , Estramenopilos/efectos de los fármacos , Fracciones Subcelulares/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Contaminantes Químicos del Agua/toxicidad
17.
Water Sci Technol ; 77(1-2): 286-295, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29377814

RESUMEN

High-resolution combined ZrO-Chelex diffusive gradients in thin film (DGT) probes were arranged to synchronously monitor the characteristics of labile phosphorus (P), iron (Fe), and manganese (Mn) in sediments from regions of varying trophic levels in Lake Taihu, China. Results showed that P release was closely related to the lake region's trophic level. Labile P in sediments and the apparent diffusion flux (Fd) of P were higher in hyper-eutrophic algae-dominated regions than those in macrophyte-algae-dominated and macrophyte-dominated regions, indicating that P released from sediments may be facilitated in eutrophic environments. A positive correlation observed between DGT-labile P and Fe or Mn, which had similar regional spatial distributions to P, showed that reductive dissolution of Fe-Mn (oxyhydr)oxides (FeOOH-MnOOH) in sediments was responsible for internal P release, which was strengthened in eutrophic environments. Ratios of labile Fe or Mn/labile P (LFe/LP and LMn/LP) in sediments in algae-dominated regions showed lower values than those in macrophyte-algae-dominated and macrophyte-dominated regions, further confirming that FeOOH-MnOOH in algae-dominated regions were less able to fix P, which brought higher pollution risks for the overlying water. LFe/LP or LMn/LP also had a significantly positive correlation with Fd, further testament that labile Fe or Mn was much more relevant to the sediment P cycle.


Asunto(s)
Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Hierro/análisis , Lagos/química , Manganeso/análisis , Fósforo/análisis , Contaminantes Químicos del Agua/análisis , China , Difusión , Eutrofización
18.
Sci Total Environ ; 563-564: 496-505, 2016 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-27152991

RESUMEN

Spatial and seasonal variations of arsenic species in Lake Taihu (including Zhushan Bay, Meiliang Bay, Gonghu Bay, and Southern Taihu) were investigated. Relatively high levels of total arsenic (TAs) and arsenate (As(V)) were observed in hyper-eutrophic regions during summer and autumn, which is attributed to exogenous contamination and seasonal endogenous release from sediments. The distributions of TAs and As(V) were significantly affected by total phosphorus, iron, manganese, and dissolved organic carbon. Arsenite (As(III)) and methylarsenicals (the sum of monomethylarsenic acid (MMA(V)) and dimethylarsenic acid (DMA(V))), mainly from biotransformation of As(V), were affected by temperature-controlled microalgae activities and local water quality parameters, exhibiting significantly higher concentrations and proportions in hyper-eutrophic and middle eutrophic regions during summer compared to mesotrophic region. The eutrophic environment, which induces changes in the main water quality parameters such as phosphorus, chlorophyll-a, iron, manganese, and dissolved organic carbon, can favor the biogeochemical cycling of arsenic in the aquatic systems.


Asunto(s)
Arsénico/análisis , Eutrofización , Lagos/química , Contaminantes Químicos del Agua/análisis , Calidad del Agua , China
19.
Luminescence ; 26(6): 734-40, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21735537

RESUMEN

This work proposes a simple and sensitive solid substrate-room temperature phosphorimetry (SS-RTP) for the selective determination of carvedilol (CV). The method is based on the sensitizing effect of sodium dodecyl benzene sulphonate (SDBS) on CV to activate the oxidation between NaClO and amaranth, resulting in the intense quenching of room temperature phosphorescence (RTP) of the system. Compared with non-SDBS system, the reduction of phosphorescence intensity (ΔI(p)) with SDBS is 16.5 times higher and is directly proportional to the content of CV, covering a wide range 0.080-16.00 fg/spot. The regression equation of the working curve can be expressed as ΔI(p) = 0.7780 + 7.057 m(CV) (fg/spot) (correlation coefficient (r) = 0.9976, n = 8), with a detection limit (LD) of 0.020 fg/spot (corresponding concentration is 5.1 × 10(-14) g/mL, sample volume is 0.40 µL/spot). This sensitive method has also been applied to determine trace CV in human plasma and the results agreed with synchronous fluorimetry (SF). The activation energy (E) and rate constant (k) of this activating reaction were 69.04 kJ/mol and 3.580 × 10(-4) s(-1), respectively. The reaction mechanism is also discussed.


Asunto(s)
Antagonistas Adrenérgicos beta/análisis , Carbazoles/análisis , Propanolaminas/análisis , Carvedilol , Límite de Detección
20.
Int J Mol Sci ; 11(6): 2373-82, 2010 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-20640158

RESUMEN

A lipase gene (atl) was cloned from Aspergillus tamarii FS132 for the first time. The gene was found to have an open reading frame of 1024 base pairs (bp), and the coding region of the gene contained two introns (51 bp and 52 bp). Multi-alignment analysis of the deduced amino acid sequence indicated high homology between the enzyme and mono-and diacylglycerol lipases from fungi Aspergillus. The recombinant lipase was expressed in Pichia pastoris GS115 cells. The recombinant lipase was found to have a molecular mass of 36.7 kDa, and it exhibited lipase activity of 20 U/mL in culture supernatant when tributyrin was used as the substrate.


Asunto(s)
Aspergillus/genética , Clonación Molecular , Proteínas Fúngicas/genética , Expresión Génica , Pichia/genética , Secuencia de Aminoácidos , Aspergillus/clasificación , Aspergillus/enzimología , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Lipasa/química , Lipasa/genética , Lipasa/metabolismo , Datos de Secuencia Molecular , Filogenia , Pichia/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN
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