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1.
Int J Biol Macromol ; 274(Pt 1): 133308, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38908619

RESUMEN

Loquat leaves are the by-product of loquat fruit production. Polysaccharides are one of the main active ingredients in loquat leaves. In this study, polysaccharides were extracted from loquat leaves by ultrasonic-assisted deep eutectic solvents (DESs) extraction method. Further, the extracted crude loquat leaf polysaccharides (CLLP) were purified and separated via S-8 resin and DEAE-52 cellulose column chromatography, respectively. Additionally, the effects of polysaccharides on activity of sperm in boar semen preserved in medium at 17 °C, were evaluated preliminarily. DES, composed of choline chloride/ethylene glycol (1:6, molar ratio), was proved to be the suitable solvent for LLP extraction. The optimized extraction conditions were water content 44 %, liquid-solid ratio 1:29 (g/g), extraction temperature 61 °C and extraction time 98 min. Under these conditions, the LLP yield was 57.82 ± 1.50 mg/g. A homogeneous polysaccharide (LLP1-2, Mw: 2.17 × 104 Da) was isolated from CLLP. Its total sugar, uronic acid and protein contents were 76.31 ± 1.25 %, 14.19 ± 0.67 % and 3.28 ± 0.42 %, respectively. Further, 800 µg/mL LLP1-2 could effectively enhance the antioxidant activity of sperm. This study laid a foundation for DESs and column chromatography in the field of polysaccharide extraction and separation, proving that LLP can be used as a natural antioxidant for sperm preservation.

2.
Int J Mol Sci ; 25(12)2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38928028

RESUMEN

Busulfan, an indispensable medicine in cancer treatment, can cause serious reproductive system damage to males as a side effect of its otherwise excellent therapeutic results. Its widespread use has also caused its accumulation in the environment and subsequent ecotoxicology effects. As a Chinese medicine, Wulingzhi (WLZ) has the effects of promoting blood circulation and improving female reproductive function. However, the potential effects of WLZ in male reproduction and in counteracting busulfan-induced testis damage, as well as its probable mechanisms, are still ambiguous. In this study, busulfan was introduced in a mouse model to evaluate its production of the testicular damage. The components of different WLZ extracts were compared using an untargeted metabolome to select extracts with greater efficacy, which were further confirmed in vivo. Here, we demonstrate abnormal spermatogenesis and low sperm quality in busulfan-injured testes. The WLZ extracts showed a strong potential to rehabilitate the male reproductive system; this effect was more prominent in room-temperature extracts. Additionally, both water and ethanol WLZ extracts at room temperature alleviated various busulfan-induced adverse effects. In particular, WLZ recovered spermatogenesis, re-activated arginine biosynthesis, and alleviated the increased oxidative stress and inflammation in the testis, ultimately reversing the busulfan-induced testicular injury. Collectively, these results suggest a promising approach to protecting the male reproductive system from busulfan-induced adverse side effects, as well as those of other similar anti-cancer drugs.


Asunto(s)
Arginina , Busulfano , Medicamentos Herbarios Chinos , Espermatogénesis , Testículo , Masculino , Animales , Busulfano/efectos adversos , Busulfano/toxicidad , Ratones , Testículo/efectos de los fármacos , Testículo/metabolismo , Espermatogénesis/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Estrés Oxidativo/efectos de los fármacos , Reproducción/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Espermatozoides/metabolismo
3.
Small ; : e2308549, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38054764

RESUMEN

Boosting the hydrogen evolution reaction (HER) activity of α-MoB2 at large current densities and in pH-universal medium is significant for efficient hydrogen production. In this work, Co2 B/MoB2 heterostructured nanoclusters are prepared by molten-salt electrolysis (MSE) and then used as a HER catalyst. The composition, structure, and morphology of Co2 B/MoB2 can be modulated by altering the stoichiometries of raw materials and synthesis temperatures. Impressively, the obtained Co2 B/MoB2 at optimized conditions exhibits a low overpotential of 297 and 304 mV at 500 mA cm-2 in 0.5 m H2 SO4 and 1 m KOH, respectively. Moreover, the Co2 B/MoB2 catalyst possesses a long-term catalytic stability of over 190 h in both acidic and alkaline medium. The excellent HER performance is due to the modified electronic structure at the Co2 B/MoB2 heterointerface where electrons are accumulated at the Mo sites to strengthen the H adsorption. Density functional theory (DFT) calculations reveal that the formation of the Co2 B/MoB2 heterointerface decreases the H adsorption and H2 O dissociation free energies, contributing to the boosted HER intrinsic catalytic activity of Co2 B/MoB2 . Overall, this work provides an experimental and theoretical paradigm for the design of efficient pH-universal boride heterostructure electrocatalysts.

4.
Mult Scler Relat Disord ; 79: 105007, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37717305

RESUMEN

OBJECTIVE: To estimate pooled prevalence of depression, anxiety, and sleep disturbances in neuromyelitis optica spectrum disorders (NMOSD) cases. METHODS: Electronic database of PubMed (MEDLINE), the Cochrane Central Register of Controlled Trials (CENTRAL), Embase and Web of Science ware systematically searched to identify relevant studies published not later than June 10, 2022. Specifically, original articles that reported the prevalence of depression, anxiety and sleep disturbances were selected. All pooled prevalence and 95 % confidence intervals (CIs) were calculated using a random-effects model. Publication bias was examined using funnel plots, and sensitivity analysis was used to explore the stability of the pooled results. RESULTS: A total of 31 studies involving 4213 participants were included in this review. The pooled prevalence of depression was 40 % (95 % CI: 32-49 %), the pooled prevalence of anxiety was 45 % (95 % CI: 24-66 %), and the pooled prevalence of sleeping disturbances was 55 % (95 % CI: 46-64 %). The depression and anxiety prevalence estimates varied based on different screening tools. CONCLUSIONS: There is a high prevalence of depression, anxiety, and sleep disturbances among NMOSD. These findings underscore the importance of regular monitoring of psychological status in NMOSD as well as the need for preventive approaches, early diagnosis, and intervention to improve medical and psychosocial outcomes.


Asunto(s)
Neuromielitis Óptica , Trastornos del Sueño-Vigilia , Humanos , Neuromielitis Óptica/complicaciones , Neuromielitis Óptica/epidemiología , Neuromielitis Óptica/psicología , Depresión/epidemiología , Prevalencia , Ansiedad/epidemiología , Trastornos del Sueño-Vigilia/epidemiología , Trastornos del Sueño-Vigilia/psicología , Sueño
5.
Sci Total Environ ; 905: 167017, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-37717764

RESUMEN

The occurrence of microplastics (MPs) within aquatic ecosystems attracts a major environmental concern. It was demonstrated MPs could cause various ecotoxicological effects on microalgae. However, existing data on the effects of MPs on microalgae showed great variability among studies. Here, we performed a meta-analysis of the latest studies on the effects of MPs on photosynthesis and oxidative stress in microalgae. A total of 835 biological endpoints were investigated from 55 studies extracted, and 37 % of them were significantly affected by MPs. In this study, the impact of MPs against microalgae was concentration-dependent and size-dependent, and microalgae were more susceptible to MPs stress in freshwater than marine. Additionally, we summarized the biological functions of microalgae that are primarily affected by MPs. Under MPs exposure, the content of chlorophyll a (Chl-a) was reduced and electron transfer in the photosynthetic system was hindered, causing electron accumulation and oxidative stress damage, which may also affect biological processes such as energy production, carbon fixation, lipid metabolism, and nucleic acid metabolism. Finally, our findings provide important insights into the effects of MPs stress on photosynthesis and oxidative stress in microalga and enhance the current understanding of the potential risk of MPs pollution on aquatic organisms.


Asunto(s)
Microalgas , Contaminantes Químicos del Agua , Microplásticos/toxicidad , Plásticos , Clorofila A , Ecosistema , Contaminantes Químicos del Agua/toxicidad , Fotosíntesis , Estrés Oxidativo
6.
J Environ Sci (China) ; 131: 48-58, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37225380

RESUMEN

Perfluorinated or polyfluorinated compounds (PFCs) continue entering to the environmental as individuals or mixtures, but their toxicological information remains largely unknown. Here, we investigated the toxic effects and ecological risks of Perfluorooctane sulfonic acid (PFOS) and its substitutes on prokaryotes (Chlorella vulgaris) and eukaryotes (Microcystis aeruginosa). Based on the calculated EC50 values, the results showed that PFOS was significantly more toxic to both algae than its alternatives including Perfluorobutane sulfonic acid (PFBS) and 6:2 Fluoromodulated sulfonates (6:2 FTS), and the PFOS-PFBS mixture was more toxic to both algae than the other two PFC mixtures. The action mode of binary PFC mixtures on Chlorella vulgaris was mainly shown as antagonistic and on Microcystis aeruginosa as synergistic, by using Combination index (CI) model coupled with Monte Carlo simulation. The mean risk quotient (RQ) value of three individual PFCs and their mixtures were all below the threshold of 10-1, but the risk of those binary mixtures were higher than that of PFCs individually because of their synergistic effect. Our findings contribute to enhance the understanding of the toxicological information and ecological risks of emerging PFCs and provide a scientific basis for their pollution control.


Asunto(s)
Chlorella vulgaris , Microcystis , Humanos , Medición de Riesgo , Agua Dulce
7.
J Colloid Interface Sci ; 634: 521-534, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36549201

RESUMEN

Herein, we engineered the cobalt core size and carbon shell thickness of Co@C by molten salt electrolysis (MSE) to investigate the enhanced essence of decreasing core size as well as the shell thickness dependence-mediated transition of catalytic mechanisms. We found that the reaction activation energy (RAE) of Co@C/peroxymonosulfate (PMS) systems was intimately dependent on the core sizes for sulfamethoxazole (SMX) degradation. The smaller core size of 26 nm provided a lower RAE of 13.39 kJ mol-1. In addition, increasing carbon shell thicknesses of Co@C altered the catalytic mechanisms from a radical pathway of SO4•- and •OH to to a non-radical pathway of 1O2 and electron-transfer process (ETP), which were verified by experimental results and density functional theory (DFT) calculations. Interestingly, increasing carbon shell thicknesses promoted the charge transfer between Co metal slab and carbon shell, increased the adsorption energy of PMS molecule on the Co@C slab, and decreased the length of OO, which favoured the occurrence of non-free radical processes.


Asunto(s)
Carbono , Peróxidos , Sulfametoxazol , Catálisis
8.
Sci Total Environ ; 855: 158906, 2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36150599

RESUMEN

As plastic pollution continues to increase and plastic waste is shredded to form smaller plastic particles, there is growing concern about the potential impact of nanoplastics (NPs) on freshwater ecosystems. In this work, the effects of three surface-modified NPs, including polystyrene (PS), PS-NH2, and PS-COOH, on the growth, photosynthetic activity, oxidative damage, and microcystins (MCs) production/release of Microcystis aeruginosa (M. aeruginosa) were investigated. Results indicated that all three NPs significantly inhibited the growth of M. aeruginosa after a 96 h exposure, and the growth inhibition followed the order of PS-NH2 > PS > PS-COOH (p < 0.05). Meanwhile, all three NPs at the concentration of 100 mg/L significantly increased the content of intra-MCs (115 %, 147 %, and 121 % higher than the control, respectively) and extra-MCs (142 %, 175 %, and 151 % higher than the control, respectively) after a 96 h exposure (p < 0.05). Moreover, our findings also suggested that the potential mechanisms of surface-modified PS NPs on M. aeruginosa growth and MCs production/release were associated with physical constraints, photosynthetic activity obstruct, and oxidative damage. Our findings provided direct evidence for different kinds of surface modifications of PS NPs on freshwater algae and improve the understanding of the potential risk of NPs in aquatic ecosystems.


Asunto(s)
Microcystis , Contaminantes Químicos del Agua , Microcistinas , Microplásticos , Ecosistema , Contaminantes Químicos del Agua/toxicidad , Poliestirenos , Plásticos/toxicidad
9.
Int J Comput Assist Radiol Surg ; 18(4): 603-610, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36272019

RESUMEN

PURPOSE: To elucidate the role of atrial anatomical remodeling in atrial fibrillation (AF), we proposed an automatic method to extract and analyze morphological characteristics in left atrium (LA), left atrial appendage (LAA) and pulmonary veins (PVs) and constructed classifiers to evaluate the importance of identified features. METHODS: The LA, LAA and PVs were segmented from contrast computed tomography images using either a commercial software or a self-adaptive algorithm proposed by us. From these segments, geometric and fractal features were calculated automatically. To reduce the model complexity, a feature selection procedure is adopted, with the important features identified via univariable analysis and ensemble feature selection. The effectiveness of this approach is well illustrated by the high accuracy of our models. RESULTS: Morphological features, such as LAA ostium dimensions and LA volume and surface area, statistically distinguished ([Formula: see text]) AF patients or AF with LAA filling defects (AF(def+)) patients among all patients. On the test set, the best model to predict AF among all patients had an area under the receiver operating characteristic curve (AUC) of 0.91 (95% CI, 0.8-1) and the best model to predict AF(def+) among all patients had an AUC of 0.92 (95% CI, 0.81-1). CONCLUSION: This study automatically extracted and analyzed atrial morphology in AF and identified atrial anatomical remodeling that statistically distinguished AF or AF(def+). The importance of identified atrial morphological features in characterizing AF or AF(def+) was validated by corresponding classifiers. This work provides a good foundation for a complete computer-assisted diagnostic workflow of predicting the occurrence of AF or AF(def+).


Asunto(s)
Apéndice Atrial , Fibrilación Atrial , Humanos , Fibrilación Atrial/diagnóstico por imagen , Apéndice Atrial/diagnóstico por imagen , Atrios Cardíacos/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Curva ROC
10.
Front Immunol ; 13: 891175, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35990668

RESUMEN

Background: The clinical outcomes of breast cancer (BC) are unpredictable due to the high level of heterogeneity and complex immune status of the tumor microenvironment (TME). When set up, multiple long non-coding RNA (lncRNA) signatures tended to be employed to appraise the prognosis of BC. Nevertheless, predicting immunotherapy responses in BC is still essential. LncRNAs play pivotal roles in cancer development through diverse oncogenic signal pathways. Hence, we attempted to construct an oncogenic signal pathway-based lncRNA signature for forecasting prognosis and immunotherapy response by providing reliable signatures. Methods: We preliminarily retrieved RNA sequencing (RNA-seq) data from The Cancer Genome Atlas (TCGA) database and extracted lncRNA profiles by matching them with GENCODE. Following this, Gene Set Variation Analysis (GSVA) was used to identify the lncRNAs closely associated with 10 oncogenic signaling pathways from the TCGA-BRCA (breast-invasive carcinoma) cohort and was further screened by the least absolute shrinkage and selection operator Cox regression model. Next, an lncRNA signature (OncoSig) was established through the expression level of the final 29 selected lncRNAs. To examine survival differences in the stratification described by the OncoSig, the Kaplan-Meier (KM) survival curve with the log-rank test was operated on four independent cohorts (n = 936). Subsequently, multiple Cox regression was used to investigate the independence of the OncoSig as a prognostic factor. With the concordance index (C-index), the time-dependent receiver operating characteristic was employed to assess the performance of the OncoSig compared to other publicly available lncRNA signatures for BC. In addition, biological differences between the high- and low-risk groups, as portrayed by the OncoSig, were analyzed on the basis of statistical tests. Immune cell infiltration was investigated using gene set enrichment analysis (GSEA) and deconvolution tools (including CIBERSORT and ESTIMATE). The combined effect of the Oncosig and immune checkpoint genes on prognosis and immunotherapy was elucidated through the KM survival curve. Ultimately, a pan-cancer analysis was conducted to attest to the prevalence of the OncoSig. Results: The OncoSig score stratified BC patients into high- and low-risk groups, where the latter manifested a significantly higher survival rate and immune cell infiltration when compared to the former. A multivariate analysis suggested that OncoSig is an independent prognosis predictor for BC patients. In addition, compared to the other four publicly available lncRNA signatures, OncoSig exhibited superior predictive performance (AUC = 0.787, mean C-index = 0.714). The analyses of the OncoSig and immune checkpoint genes clarified that a lower OncoSig score meant significantly longer survival and improved response to immunotherapy. In addition to BC, a high OncoSig score in several other cancers was negatively correlated with survival and immune cell infiltration. Conclusions: Our study established a trustworthy and discriminable prognostic signature for BC patients with similar clinical profiles, thus providing a new perspective in the evaluation of immunotherapy responses. More importantly, this finding can be generalized to be applicable to the vast majority of human cancers.


Asunto(s)
Neoplasias de la Mama , ARN Largo no Codificante , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/terapia , Carcinogénesis/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunoterapia , Pronóstico , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Transducción de Señal/genética , Microambiente Tumoral/genética
11.
Pathol Res Pract ; 237: 153996, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35839610

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is among the most prevalent cancers. Long non-coding RNAs (lncRNAs) are important participant in various cancers. Based on the literature, lncRNA RASSF8-AS1 inhibits laryngeal squamous cell carcinoma (LSCC) malignant progression. However, the role of RASSF8-AS1 in CRC remains unclear. PURPOSE: This study centered on uncovering the role of RASSF8-AS1 and its related regulatory mechanisms in CRC cells. METHODS: RT-qPCR and western blot were performed to examine the expression of target genes. Functional assays were conducted to determine the effect of target genes on the migration and invasion of CRC cells. Mechanism assays were also carried out to figure out the specific downstream mechanisms of RASSF8-AS1. In vivo assays were also involved. RESULTS: The expression of RASSF8-AS1 and RASSF8 was positively correlated in CRC, and the two genes were down-regulated in CRC cells and tissues. Moreover, CRC cell invasion and migration as well as xenograft CRC tumor growth suppressed by RASSF8-AS1 overexpression were entirely recovered by RASSF8 knockdown or partially rescued by miR-33a-5p augment. As for the downstream mechanism, RASSF8-AS1 sponged miR-33a-5p to up-regulate RASSF8, or recruited HNRNPC to stabilize RASSF8 mRNA. CONCLUSION: RASSF8-AS1 modulates miR-33a-5p/HNRNPC/RASSF8 axis to further impede CRC cell invasion and migration. AVAILABILITY OF DATA: The research data is confidential.


Asunto(s)
Neoplasias Colorrectales , MicroARNs , ARN Largo no Codificante , Humanos , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Neoplasias Colorrectales/patología , Regulación Neoplásica de la Expresión Génica/genética , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , ARN Mensajero , Proteínas Supresoras de Tumor/metabolismo , Animales
12.
J Hazard Mater ; 437: 129355, 2022 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-35716567

RESUMEN

Since traditional Per- and polyfluoroalkyl substances (PFAS) were banned in 2009 due to their bioaccumulation, persistence and biological toxicity, the emerging PFAS have been widely used as their substitutes and entered the aquatic environment in the form of mixtures. However, the joint toxicity mechanisms of these emerging PFAS mixtures to aquatic organisms remain largely unknown. Then, based on the testing of growth inhibition, cytotoxicity, photosynthesis and oxidative stress, and the toxicity mechanism of PFAS mixture (Perfluorobutane sulfonate and Perfluorobutane sulfonamide) to algae was explored using the Gene set enrichment analysis (GSEA). The results revealed that all three emerging PFAS treatments had a certain growth inhibitory effect on Chlorella pyrenoidosa (C. pyrenoidosa), but the toxicity of PFAS mixture was stronger than that of individual PFAS and showed a significant synergistic effect at environmental concentration. The joint toxicity mechanisms of binary PFAS mixture to C. pyrenoidosa were related to the damage of photosynthetic system, obstruction of ROS metabolism, and inhibition of DNA replication. Our findings are conductive to adding knowledge in understanding the joint toxicity mechanisms and provide a basis for assessing the environmental risk of emerging PFAS.


Asunto(s)
Chlorella , Fluorocarburos , Contaminantes Químicos del Agua , Bioacumulación , Fluorocarburos/toxicidad , Fotosíntesis , Contaminantes Químicos del Agua/toxicidad
13.
J Hazard Mater ; 426: 128094, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-34952496

RESUMEN

Nylon has been widely used all over the world, and most of it eventually enters the aquatic environment in the form of microplastics (MPs). However, the impact of Nylon MPs on aquatic ecosystem remains largely unknown. Thus, the long-term biological effects and toxicity mechanism of Nylon MPs on Microcystis aeruginosa (M. aeruginosa) were explored in this study. Results demonstrated that Nylon MPs had a dose-dependent growth inhibition of M. aeruginosa at the initial stage, and the maximum inhibition rate reached to 47.62% at the concentration of 100 mg/L. Meanwhile, Nylon MPs could obstruct photosynthesis electron transfer, reduce phycobiliproteins synthesis, destroy algal cell membrane, enhance the release of extracellular polymeric substances, and induce oxidative stress. Furthermore, transcriptomic analysis indicated that Nylon MPs dysregulated the expression of genes involved in tricarboxylic acid cycle, photosynthesis, photosynthesis-antenna proteins, oxidative phosphorylation, carbon fixation in photosynthetic organisms, and porphyrin and chlorophyll metabolism. According to the results of transcriptomic and biochemical analysis, the growth inhibition of M. aeruginosa is inferred to be regulated by three pathways: photosynthesis, oxidative stress, and energy metabolism. Our findings provide new insights into the toxicity mechanism of Nylon MPs on freshwater microalgae and valuable data for risk assessment of MPs.


Asunto(s)
Microcystis , Contaminantes Químicos del Agua , Ecosistema , Transporte de Electrón , Microplásticos , Nylons/toxicidad , Estrés Oxidativo , Fotosíntesis , Plásticos , Contaminantes Químicos del Agua/toxicidad
14.
Sci Total Environ ; 797: 149005, 2021 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-34311359

RESUMEN

GenX, a substitute for perfluorooctanoic acid, has been widely detected in surface water. Due to its bioaccumulation, toxicity and persistence, GenX can cause adverse effects such as oxidative damage on aquatic organisms. To investigate the toxicity of GenX and the anti-oxidant mechanism of algae under acute exposure, the growth, photosynthetic activity and gene expression of Chlorella pyrenoidosa (C. pyrenoidosa) were tested. Results showed that the growth of C. pyrenoidosa was inhibited under acute GenX exposure. The toxicity of GenX increased with time and concentration but was lower than that of the traditional perfluoroalkyl and polyfluoroalkyl substances (PFASs). Furthermore, with the increase of GenX concentration, the production of reactive oxygen species increased, while the level of the anti-oxidant enzyme first increased and then decreased. Changes in photosynthetic parameters also indicated that the photosynthetic system of C. pyrenoidosa was negatively affected by GenX exposure. Transcription analysis revealed that the up-regulation of genes related to the glutathione-ascorbate cycle and photosynthesis is a positive strategy to cope with the oxidative stress caused by acute GenX exposure. Our findings provide new insights into the interactions between emerging PFASs and aquatic organisms at the molecular level.


Asunto(s)
Chlorella , Antioxidantes , Bioacumulación , Chlorella/metabolismo , Glutatión/metabolismo , Fotosíntesis
15.
Ecotoxicol Environ Saf ; 208: 111575, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396101

RESUMEN

Microplastics (MPs) have aroused widespread concern due to their extensive distribution in aquatic environments and adverse effects on aquatic organisms. However, the underlying toxicity of different kinds of MPs on freshwater microalgae has not been examined in detail. In this study, we investigated the effects of polyvinyl chloride (PVC), polystyrene (PS) and polyethylene (PE) MPs on the growth of Microcystis aeruginosa, as well as on its toxin production and oxidative stress. We found that all three kinds of MPs had an obvious inhibition effect on the growth of M. aeruginosa. Considering the results of antioxidant-related indicators, the activity of superoxide dismutase (SOD) and catalase (CAT), and cell membrane integrity were greatly affected with exposure to PVC, PS and PE MPs. Moreover, the content of intracellular (intra-) and extracellular (extra-) microcystins (MCs) had a noticeable increase due to the presence of PVC, PS, and PE MPs. Finally, according to the comprehensive stress resistance indicators, the resistance of M. aeruginosa to three MPs followed the order: PE (3.701)> PS (3.607)> PVC (2.901). Our results provide insights into the effects of different kinds of MPs on freshwater algae and provide valuable data for risk assessment of different types of MPs.


Asunto(s)
Microcystis/fisiología , Microplásticos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Antioxidantes/metabolismo , Catalasa/metabolismo , Agua Dulce , Microalgas/efectos de los fármacos , Microcistinas , Microcystis/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Plásticos/toxicidad , Polietileno , Poliestirenos/toxicidad , Cloruro de Polivinilo/toxicidad , Superóxido Dismutasa/metabolismo
16.
Sci Total Environ ; 765: 144431, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33387923

RESUMEN

Perfluorooctanoic acid (PFOA) and its substitute GenX are toxic chemicals that are widespread in the aquatic environment. However, there is little information about their toxicity mechanisms to aquatic organisms. In this study, Chlorella pyrenoidosa (C. pyrenoidosa) was treated with two concentrations (100 ng L-1 and 100 µg L-1) of PFOA or GenX for 12 days. The results showed that these two concentrations of PFOA and GenX began to inhibit the growth of algae after 6 days of treatment, and the Chlorophyll content and photosynthetic activity of C. pyrenoidosa were also negatively affected by these two chemicals. The transcriptomic results indicated that most of the genes related to the photosynthetic metabolism of C. pyrenoidosa were down-regulated (in 100 ng L-1 treatment groups) on the 12th day. Besides, GenX and PFOA showed similar effects on algae photosynthesis including physical damage and metabolic disorders. According to this study, GenX might not be an ideal substitute for PFOA, and more attention should be paid on the management of emerging perfluoroalkyl substances.


Asunto(s)
Chlorella , Fluorocarburos , Contaminantes Químicos del Agua , Caprilatos , Fluorocarburos/toxicidad , Fotosíntesis , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
17.
Environ Sci Pollut Res Int ; 28(11): 13394-13403, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33180284

RESUMEN

Nanoplastics are widely distributed in freshwater environments, but few studies have addressed their effects on freshwater algae, especially on harmful algae. In this study, the effects of polystyrene (PS) nanoplastics on Microcystis aeruginosa (M. aeruginosa) growth, as well as microcystin (MC) production and release, were investigated over the whole growth period. The results show that PS nanoplastics caused a dose-dependent inhibitory effect on M. aeruginosa growth and a dose-dependent increase in the aggregation rate peaking at 60.16% and 46.34%, respectively, when the PS nanoplastic concentration was 100 mg/L. This caused significant growth of M. aeruginosa with a specific growth rate up to 0.41 d-1 (50 mg/L PS nanoplastics). After a brief period of rapid growth, the tested algal cells steadily grew. In addition, the increase in PS nanoplastics concentration promoted the production and release of MC. When the PS nanoplastic concentration was 100 mg/L, the content of the intracellular (intra-) and extracellular (extra-) MC increased to 199.1 and 166.5 µg/L, respectively, on day 26, which was 31.4% and 31.1% higher, respectively, than the control. Our results provide insights into the action mechanism of nanoplastics on harmful algae and the potential risks to freshwater environments.


Asunto(s)
Microcystis , Microcistinas , Microplásticos , Poliestirenos
18.
Clin Epigenetics ; 12(1): 162, 2020 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-33126908

RESUMEN

BACKGROUND AND AIMS: Stool DNA testing is an emerging and attractive option for colorectal cancer (CRC) screening. We previously evaluated the feasibility of a stool DNA (sDNA) test of methylated SDC2 for CRC detection. The aim of this study was to assess its performance in a multicenter clinical trial setting. METHODS: Each participant was required to undergo a sDNA test and a reference colonoscopy. The sDNA test consists of quantitative assessment of methylation status of SDC2 promoter. Results of real-time quantitative methylation-specific PCR were dichotomized as positive and negative, and the main evaluation indexes were sensitivity, specificity, and kappa value. All sDNA tests were performed and analyzed independently of colonoscopy. RESULTS: Among the 1110 participants from three clinical sites analyzed, 359 and 38 were diagnosed, respectively, with CRC and advanced adenomas by colonoscopy. The sensitivity of the sDNA test was 301/359 (83.8%) for CRC, 16/38 (42.1%) for advanced adenomas, and 134/154 (87.0%) for early stage CRC (stage I-II). Detection rate did not vary significantly according to age, tumor location, differentiation, and TNM stage, except for gender. The follow-up testing of 40 postoperative patients with CRC returned negative results as their tumors had been surgically removed. The specificity of the sDNA test was 699/713 (98.0%), and unrelated cancers and diseases did not seem to interfere with the testing. The kappa value was 0.84, implying an excellent diagnostic consistency between the sDNA test and colonoscopy. CONCLUSION: Noninvasive sDNA test using methylated SDC2 as the exclusive biomarker is a clinically viable and accurate CRC detection method. CHINESE CLINICAL TRIAL REGISTRY: Chi-CTR-TRC-1900026409, retrospectively registered on October 8, 2019; http://www.chictr.org.cn/edit.aspx?pid=43888&htm=4 .


Asunto(s)
Adenoma/genética , Neoplasias Colorrectales/genética , ADN/análisis , Heces/química , Sindecano-2/genética , Adenoma/diagnóstico , Adulto , Anciano , Biomarcadores de Tumor/genética , Estudios de Casos y Controles , Neoplasias del Colon/patología , Colonoscopía/métodos , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/cirugía , Metilación de ADN , Detección Precoz del Cáncer/métodos , Estudios de Evaluación como Asunto , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias/métodos , Regiones Promotoras Genéticas , Sensibilidad y Especificidad
19.
J Thorac Dis ; 12(5): 2333-2342, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32642138

RESUMEN

BACKGROUND: Previous studies have already established that low platelet count is related to adverse outcomes in patients with type A acute aortic dissection (AAAD). However, there are yet limited studies investigating the association of platelet count and the risk of postoperative pneumonia in AAAD patients. METHODS: This retrospective cohort study was conducted in Xiangya Hospital of Central South University from January 2014 to May 2019. Clinical and laboratory data were collected. The correlation between platelet count and postoperative pneumonia was analyzed using multivariate logistic regression and the area under the receiver operating characteristic curve (AUC) was used to assess the predictive power of platelet count on pneumonia. RESULTS: A total of 268 patients with AAAD were enrolled. The overall incidence of pneumonia was 36.94% (n=99). Multivariate logistic regression revealed that platelet count was negatively associated with the risk of postoperative pneumonia (OR 0.93; 95% CI: 0.88-0.98) after adjusting for the confounders. Compared to the lowest platelet count tertile (T1), medium platelet count (T2) and highest platelet count (T3) had a lower risk of postoperative pneumonia after adjusting for the confounders (OR 0.80, 95% CI: 0.40-1.60; OR 0.30, 95% CI: 0.13-0.66; respectively). A similar trend was observed when the platelet count was handled as categorical variables (tertiles). The area under the ROC curve was 0.635 (95% CI: 0.565-0.707), with a sensitivity of 76.77%, a specificity of 50.89% and an accuracy of 60.45%. CONCLUSIONS: Our findings indicate that low platelet count is an independent risk factor of postoperative pneumonia in patients with AAAD and has a specific predictive power on the risk of postoperative pneumonia.

20.
Talanta ; 211: 120713, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32070622

RESUMEN

Bisphenols, a typical pollutant with endocrine acting the scientific attention for their ascertained toxicity and wide uses. The magnetic Zr-MOFs (Fe3O4@PDA@UiO-66-NH2), functionalized with amino groups and proved by a series of material characterization techniques, were successfully prepared as adsorbents for magnetic solid-phase extraction (MSPE) of five bisphenols (including bisphenol A, bisphenol B, bisphenol S, bisphenol AP and bisphenol AF) from water samples. Liquid chromatography coupled with tandem mass spectrometry was used for sample analysis and quantification. Good linearity was obtained for each analyte with correlation coefficients larger than 0.990. The low limits of detection (LOD) and qualification (LOQ) were 0.013-0.290 µg/L (S/N = 3) and 0.088-1.800 µg/L (S/N = 10), respectively. The repeatability standard deviations in spiked lake water samples were 0.57-1.67%. In addition, the amount of the materials (40 mg), the adsorption time (30 min), pH value (7), elution time (30 min) and elution solvent (methanol) were determined as the optimal parameters in bisphenol extraction. Satisfactory results were obtained when the developed MSPE method was applied to determine the five bisphenols in real lake water samples, and the maximum extraction efficiency was up to 78.2%. The developed MSPE method using the Fe3O4@PDA@UiO-66-NH2 as adsorbent provides time saving, high selectivity and sensitivity for the analysis of trace bisphenols, suggesting that the Fe3O4@PDA@UiO-66-NH2 had a broad application prospect in water analysis.

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