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1.
Ecotoxicol Environ Saf ; 273: 116143, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38430582

RESUMEN

Coral reefs are essential for marine ecology and biodiversity. Global climate change has resulted in severe coral reef degradation, partly via coral bleaching, which is caused by rising sea temperatures and solar light intensity. In this study, we examined the impact of strong light (300 µmol.m-2.s-1) and high temperature (33°C) on the growth, immunity, and gene expression of Galaxea fascicularis. Strong light caused coral bleaching in the absence of high sea temperatures, while no obvious bleaching was observed under high temperature alone. The effect of strong light on calcification rate of G. fascicularis is significantly weaker than that of high temperature. Both strong light and high temperatures significantly affected the immune enzyme activity of G. fascicularis symbionts, with the former having a strong effect on their photosystem. Temperature affected the digestive system, replication and repair, and cell growth and death of coral hosts, as indicated by transcriptomics analysis. These results provide a valuable for strategies to mitigate coral bleaching. TEASER: We explored the effects of strong light exposure and high temperature on coral reefs and their symbiont algae.


Asunto(s)
Antozoos , Animales , Antozoos/genética , Temperatura , Transcriptoma , Arrecifes de Coral , Luz
2.
Cancer Sci ; 113(5): 1587-1600, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35178836

RESUMEN

Evolutionarily conserved DDB1-and CUL4-associated factor 13 (DCAF13) is a recently discovered substrate receptor for the cullin RING-finger ubiquitin ligase 4 (CRL4) E3 ubiquitin ligase that regulates cell cycle progression. DCAF13 is overexpressed in many cancers, although its role in breast cancer is currently elusive. In this study we demonstrate that DCAF13 is overexpressed in human breast cancer and that its overexpression closely correlates with poor prognosis, suggesting that DCAF13 may serve as a diagnostic marker and therapeutic target. We knocked down DCAF13 in breast cancer cell lines using CRISPR/Cas9 and found that DCAF13 deletion markedly reduced breast cancer cell proliferation, clone formation, and migration both in vitro and in vivo. In addition, DCAF13 deletion promoted breast cancer cell apoptosis and senescence, and induced cell cycle arrest in the G1/S phase. Genome-wide RNAseq analysis and western blotting revealed that loss of DCAF13 resulted in both mRNA and protein accumulation of p53 apoptosis effector related to PMP22 (PERP). Knockdown of PERP partially reversed the hampered cell proliferation induced by DCAF13 knockdown. Co-immunoprecipitation assays revealed that DCAF13 and DNA damage-binding protein 1 (DDB1) directly interact with PERP. Overexpression of DDB1 significantly increased PERP polyubiquitination, suggesting that CRL4DCAF13 E3 ligase targets PERP for ubiquitination and proteasomal degradation. In conclusion, DCAF13 and the downstream effector PERP occupy key roles in breast cancer proliferation and potentially serve as prognostics and therapeutic targets.


Asunto(s)
Neoplasias de la Mama , Factor XIII , Neoplasias de la Mama/genética , Proliferación Celular/genética , Proteínas Cullin/genética , Factor XIII/genética , Factor XIII/metabolismo , Femenino , Genes Supresores de Tumor , Humanos , Proteínas de la Membrana/metabolismo , Proteínas de Unión al ARN/genética , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación
3.
Ecotoxicol Environ Saf ; 229: 113074, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34915224

RESUMEN

The amino acid metabolism-related herbicides glufosinate and glyphosate are used worldwide and have flowed into the oceans, threatening the marine organisms. In the present study, physiological activities and transcriptomic profiles of the scleractinian coral Pocillopora damicornis and symbiotic Symbiodiniaceae were determined during a 48 h-exposure to the two herbicides with the final concentration of 10 µmol L-1. Coral samples were collected at 0, 12, 24, and 48 h after exposure to determine symbiont density, chlorophyll content, as well as activities of superoxide dismutase (SOD), catalase (CAT), nitric oxide synthetase (NOS) and phenoloxidase (PO), and the caspase-3 levels, and the samples collected at 24 h were employed in the transcriptomic analysis. Specifically, the symbiont densities did not change significantly in response to the two herbicides, while the chlorophyll content increased significantly at 24 h post glufosinate exposure. SOD and CAT activities in the coral host increased significantly at 12 h after glufosinate and glyphosate exposure, while the activity of NOS in symbionts decreased significantly at 48 h after glufosinate exposure. Caspase-3 levels in the coral host declined significantly at 24 h after exposure to the two herbicides. In the transcriptomic analysis, glufosinate triggered the expression of genes related to the response to stimuli and immunoregulation in the coral host, and suppressed the expression of genes related to coral nitrogen-related metabolism, symbiont cell cycle, and response to nutrient levels. Furthermore, glyphosate activated the expression of genes involved in coral calcification and symbiont nutrient export and suppressed the expression of genes involved in coral meiosis and symbiont cell communication. These results suggest that although the coral-Symbiodiniaceae symbiosis is not disrupted, short-term glufosinate and glyphosate exposures alter several essential physiological processes including metabolism, calcification, and meiosis in the coral host, as well as the cell cycle and nutrient export in the symbiont. SUMMARY: Glufosinate and glyphosate herbicide exposures can disturb several essential physiological processes, including metabolism, calcification, and meiosis in the coral host as well as the cell cycle and nutrient export in the symbiont, threating the survival of scleractinian corals.


Asunto(s)
Antozoos , Dinoflagelados , Herbicidas , Aminobutiratos , Animales , Antozoos/genética , Dinoflagelados/genética , Glicina/análogos & derivados , Herbicidas/toxicidad , Simbiosis , Transcriptoma , Glifosato
4.
Sensors (Basel) ; 22(17)2022 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-36080932

RESUMEN

Multi-dimensional parameters joint estimation of multi-targets is introduced to implement super-resolution sensing in range, velocity, azimuth angle, and elevation angle for frequency-modulated continuous waveform (FMCW) radar systems. In this paper, a low complexity joint 3D super-resolution estimation of range, velocity, and angle of multi-targets is proposed for an FMCW radar with a uniform linear array. The proposed method firstly constructs the size-reduced 3D matrix in the frequency domain for the system model of an FMCW radar system. Secondly, the size-reduced 3D matrix is established, and low complexity three-level cascaded 1D spectrum estimation implemented by applying the Lagrange multiplier method is developed. Finally, the low complexity joint 3D super-resolution algorithms are validated by numerical experiments and with a 77 GHz FMCW radar built by Texas Instruments, with the proposed algorithm achieving significant estimation performance compared to conventional algorithms.

5.
Org Biomol Chem ; 16(3): 414-423, 2018 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-29261209

RESUMEN

In the presence of Ru(phen)3Cl2 or fac-Ir(ppy)3 under visible-light irradiation, the addition of fluorinated radicals to N-arylacrylamides followed by an intramolecular cyano group insertion cascade cyclization process produced trifluoroalkyl or difluoroalkyl phenanthridine derivatives in moderate to good yields. Three easily available fluoroalkylated reagents CF3SO2Cl, BrCF2CO2Et and BrCF2PO(OEt)2 were used as the sources of fluorinated radicals.

6.
Org Biomol Chem ; 15(25): 5318-5324, 2017 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-28613336

RESUMEN

The C3-azolylation of imidazo[1,2-a]pyridines was developed via a visible light-mediated reaction of imidazopyridines with 2-bromoazoles catalyzed by Ir(ppy)2(dtbbpy)PF6 under mild conditions. For the imidazo[1,2-a]pyridines with various substituents on benzene or the pyridine ring and a variety of azoles, the reaction proceeded smoothly to give 3-(azol-2-yl)imidazo[1,2-a]pyridines in moderate to good yields.

7.
J Org Chem ; 80(24): 12588-93, 2015 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-26539743

RESUMEN

2-(Alkylamino)benzonitriles were synthesized via a rhodium-catalyzed cyanation on the aryl C-H bond and subsequent denitrosation of N-nitrosoarylamines using a removable nitroso as the directing group, in which N-cyano-N-phenyl-p-methylbenzenesulfonamide (NCTS) was used as the "CN" source. Various substituents on the aryl ring and amino group of N-nitrosoarylamines tolerated the reaction, and the corresponding products were achieved in moderate to good yields.

8.
Chemosphere ; 352: 141309, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38281603

RESUMEN

Microplastics become hotspots for bacteria to trigger a series of ecological effects, but few studies have focused on the potential impacts of microplastic biofilms in coral reef ecosystems. Here, we measured the bacterial communities and antibiotic resistance genes (ARGs) in the seawater and microplastic biofilms. Results showed that microbial biofilms were formed on the surface of microplastics. The alpha diversity of the bacterial community in the microplastic biofilms was lower than that in the seawater, and the bacterial communities were distinct between the two. Further analysis revealed that several bacteria in the microplastic biofilms carried ARGs, and the proportion of which was correlated to the concentration of antibiotics in the seawater. Specifically, Vibrio was positively correlated to sul1 in the microplastic biofilms under higher concentrations of sulfonamides. Pathway analysis reflected significant overrepresentation of human disease related pathways in the bacterial community of microplastic biofilms. These results suggest that the microplastic biofilms could selectively enrich bacteria from the reef environments, causing the development of ARGs under antibiotic driving. This may pose a serious threat to coral reef ecosystems and human health. Our study provides new insights into the ecological impacts of microplastic biofilms in coral reef ecosystems.


Asunto(s)
Arrecifes de Coral , Microplásticos , Humanos , Ecosistema , Plásticos , Antibacterianos/toxicidad , Bacterias/genética , Farmacorresistencia Microbiana , Biopelículas
9.
Nanotechnology ; 24(46): 465603, 2013 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-24157576

RESUMEN

Putting metals into organic compounds such as peptides can lead to many new desirable properties. Here we designed a novel bioorganometallic molecule, ferrocene-diphenylalanine (Fc-FF), and investigated its self-assembly behavior. We directly observed a morphological transition from metastable nanospheres to nanofibers, which led to the formation of a self-supporting hydrogel. The strong hydrophobic interaction of the Fc moiety was suggested to have a key role in this kinetically controlled self-assembly process. Moreover, the redox center of the ferrocene group further allowed us to reversibly control the self-assembly behavior of Fc-FF by altering its redox state.


Asunto(s)
Compuestos Ferrosos/química , Nanocompuestos/química , Nanofibras/química , Fenilalanina/análogos & derivados , Dicroismo Circular , Dipéptidos , Interacciones Hidrofóbicas e Hidrofílicas , Cinética , Luz , Metalocenos , Nanotecnología , Oxidación-Reducción , Tamaño de la Partícula , Fenilalanina/química , Reología , Dispersión de Radiación
10.
Zhongguo Fei Ai Za Zhi ; 26(3): 193-203, 2023 Mar 20.
Artículo en Zh | MEDLINE | ID: mdl-37035882

RESUMEN

BACKGROUND: Primary mediastinal germ cell tumor (PMGCT) is a rare but occasionally highly invasive mediastinal tumor. At present, there are few related disease special survival (DSS) studies on PMGCT, rare large data analysis, and uncommon DSS prognostic models. This study was to investigate the prognostic factors of DSS of the PMGCT patients, and build a simple and effective nomogram to predict the DSS prognosis in patients with PMGCT. METHODS: Retrospective clinicopathological data of 325 patients with PMGCT from 1975 to 2019 were extracted from Surveillance, Epidemiology, and End Results (SEER) database. The Kaplan-Meier method along with the Log-rank test were utilized to estimate the DSS. Cox proportional hazard regression model was used to screen the independent risk factors affecting prognosis, from which an individualized nomogram was constructed to predict 3-yr, 5-yr and 8-yr DSS of patients with PMGCT. The prediction accuracy of the model is evaluated by receiver operating characteristic (ROC) curve, correction curve and decision curve analysis (DCA) curve. RESULTS: The 3-yr, 5-yr and 8-yr survival rates of PMGCT were 84.6%, 83.6% and 83.3%, respectively. Univariate analysis showed that histology, surgery, age, tumor size, metastasis and stage could affect the prognosis of PMGCT. Multivariate analysis showed that histology, surgery, age and tumor size were independent risk factors for the prognosis of PMGCT patients, and the nomogram was constructed using these independent risk factors. The area under the curve (AUC) of ROC curve was 0.824. The results of the correction curves of 3-yr, 5-yr and 8-yr survival time and DCA, indicated that there was a good consistency between the predicted results of the nomogram evaluation and the real results. CONCLUSIONS: Patients with histological classification of seminoma in PMGCT have a better prognosis than patients with non-seminoma. The prognosis of patients with over the age of 40 yr, tumor size ≥15 cm and without surgical treatment was even worse. The nomogram model can accurately and intuitively predict the DSS of patients with PMGCT.


Asunto(s)
Neoplasias Pulmonares , Neoplasias del Mediastino , Neoplasias de Células Germinales y Embrionarias , Humanos , Nomogramas , Estudios Retrospectivos , Pronóstico
11.
Mar Pollut Bull ; 191: 114897, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37043929

RESUMEN

Loss of oxygen in the ocean is accelerating and threatening the coral reef ecosystem. In this study, the impacts of hypoxia on the scleractinian coral Pocillopora damicornis were explored. The algal symbiont density, chlorophyll a + c2 content, energy consumption of corals, as well as energy available and consumption of their symbionts, decreased significantly post hypoxia stress. Meanwhile, the malondialdehyde contents in corals and symbionts, together with the caspase-3 activation level in corals, increased significantly in response to hypoxia stress. Furthermore, it was revealed that activities such as coral cell division and calcification were inhibited under hypoxia. These results collectively suggest that acute hypoxia stress reduces symbiont density and chlorophyll a + c2 content in the coral P. damicornis by elevating intracellular oxidative pressure and apoptotic level, which further suppresses energy metabolism in the symbiotic association and negatively affects a series of activities such as coral cell division and calcification.


Asunto(s)
Antozoos , Animales , Antozoos/fisiología , Ecosistema , Clorofila A/metabolismo , Arrecifes de Coral , Hipoxia , Metabolismo Energético , Simbiosis
12.
Front Oncol ; 13: 1186991, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37719018

RESUMEN

Objective: This study aimed to investigate and analyze the clinical application value of thoracoscopic segmentectomy and lobectomy in patients with invasive pulmonary adenocarcinoma. Methods: 286 patients with invasive pulmonary adenocarcinoma who underwent segmentectomy or lobectomy at the First Hospital of Jiaxing City from January 2018 to June 2020 were retrospectively analyzed. Patients were divided into a thoracoscopic segmentectomy group(n=97) and a lobectomy group (n=189). Patients were compared after obtaining 1:1 propensity score-matched cohorts. Outcome indicators included surgery-related indicators, immune-inflammation-related indicators, postoperative complications, recurrence, and metastasis. Results: After 1:1 propensity score matching, 93 patients were included in each group. We found that the volume of intraoperative blood loss in the segmentectomy group was significantly less than in the lobectomy group (P=0.014). The duration of postoperative drainage (P = 0.005) and hospitalization (P=0.002) in the segmentectomy group were significantly shorter than in the lobectomy group. In terms of immunoinflammatory response, compared with the lobectomy group, white blood cells, neutrophils, SII, and NLR in the segmentectomy group were significantly lower than in the lobectomy group (P< 0.05). The recurrence-free survival (RFS) rates in the segmentectomy and lobectomy were 80.5% and 88.2% at 1 year and 35.1% and 52.6% at 3 years, respectively, and the difference was statistically significant (P<0.05). The segmentectomy group achieved similar outcomes to the lobectomy group at 1 year and 3 years (P > 0.05). Multivariate COX regression analysis showed that CAR was an independent risk factor for RFS in patients undergoing invasive adenocarcinoma surgery. Conclusion: Compared with lobectomy, thoracoscopic segmentectomy can effectively reduce the postoperative inflammatory response in patients with early invasive lung adenocarcinoma and promote patient recovery. Although segmentectomy is associated with a higher recurrence rate in the short term for patients with early invasive lung adenocarcinoma, the associated survival rate is similar to the lobectomy group. Segmentectomy should be considered in the treatment of early invasive lung adenocarcinoma. Meanwhile, postoperative CAR represents an independent risk factor for early postoperative recurrence in patients with IAC.

13.
Environ Pollut ; 316(Pt 1): 120565, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36332711

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are highly toxic environmental pollutants and are threatening scleractinian corals. In this study, PAHs treatment did not induce significant physiological responses of the coral Pocillopora damicornis and its algal symbionts, but biological processes including response to toxin, drug metabolic, and oxidation reduction were triggered at the mRNA level. These results implied that PAHs could be a group of slow-acting environmental toxicants, whose effects were moderate but persistent. Besides, it was interesting to find that PAHs activated the neuroendocrine system in the coral by triggering the expression of monoaminergic and acetylcholinergic system related genes, indicating that PAHs might function as environmental hormones. Moreover, the combined treatments of PAHs and heat caused a much obvious effect on the coral and its algal symbionts by elevating antioxidant activity and suppressing photosynthesis in the symbionts. Results from the transcriptome data further indicated that corals might perform stress responses upon PAHs and heat challenges through the TNF and apoptosis pathways, which perhaps was modulated by the neuroendocrine system of corals. Collectively, our survey demonstrates that the PAHs can function as environmental hormones and activate the neuroendocrine regulation in scleractinian corals, which may contribute to the stress responses of symbiotic association by modulating photosynthesis, antioxidation, and apoptosis.


Asunto(s)
Antozoos , Hidrocarburos Policíclicos Aromáticos , Animales , Antozoos/fisiología , Hidrocarburos Policíclicos Aromáticos/toxicidad , Hidrocarburos Policíclicos Aromáticos/metabolismo , Respuesta al Choque Térmico , Sistemas Neurosecretores , Hormonas , Arrecifes de Coral
14.
J Hazard Mater ; 454: 131500, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37116329

RESUMEN

Seagrasses are important foundation species in coastal ecosystems, and they provide food and habitat that supports high biodiversity. However, seagrasses are increasingly subjected to anthropogenic disturbances such as metal pollution, which has been implicated as a significant factor driving seagrass losses. There have been several reviews synthesizing the metal concentrations in seagrasses and evaluating their utility as biomonitors for metal pollution in the coastal environment at the local scale. However, the interpretation of metal data in seagrass biomonitors requires a more mechanistic understanding of the processes governing metal bioaccumulation and detoxification. In this review, the progress and trends in metal studies in seagrasses between 1973 and 2022 were analyzed to identify frontier topics in this field. In addition, we tried to (1) analyze and assess the current status of metal contamination in seagrasses on a global scale by incorporating more metal data from tropical and Indo-Pacific seagrasses, (2) summarize the geochemical and biological factors governing metal uptake and loss in seagrasses, and (3) provide an up-to-date understanding of metals' effects on seagrasses and their physiological responses to metal challenges. This review improves our understanding of the highly variable metal concentrations observed in the field.


Asunto(s)
Ecosistema , Metales , Cinética , Biodiversidad
15.
J Robot Surg ; 17(5): 2323-2330, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37368225

RESUMEN

We use machine learning to evaluate surgical skill from videos during the tumor resection and renography steps of a robotic assisted partial nephrectomy (RAPN). This expands previous work using synthetic tissue to include actual surgeries. We investigate cascaded neural networks for predicting surgical proficiency scores (OSATS and GEARS) from RAPN videos recorded from the DaVinci system. The semantic segmentation task generates a mask and tracks the various surgical instruments. The movements from the instruments found via semantic segmentation are processed by a scoring network that regresses (predicts) GEARS and OSATS scoring for each subcategory. Overall, the model performs well for many subcategories such as force sensitivity and knowledge of instruments of GEARS and OSATS scoring, but can suffer from false positives and negatives that would not be expected of human raters. This is mainly attributed to limited training data variability and sparsity.


Asunto(s)
Laparoscopía , Procedimientos Quirúrgicos Robotizados , Cirujanos , Humanos , Procedimientos Quirúrgicos Robotizados/métodos , Nefrectomía/educación
16.
Mitochondrial DNA B Resour ; 7(7): 1299-1301, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35874277

RESUMEN

In this study, the complete mitochondrial genome (mitogenome) of Sinularia humilis van Ofwegen, 2008 was determined using next-generation sequencing (NGS) method. The mitogenome of S. humilis is 18,743 bp in length, containing 14 protein-coding genes (PCGs), two ribosomal RNAs (rRNA) and one tRNA (tRNA-Met), which has same gene order with other species of Sinularia. ATG was determined as start codon in all 14 PCGs. Eight TAG, five TAA, and one incomplete codons (T-) were found as stop codon. Phylogenetic analysis of the small number of available mitogenomes showed that S. humilis is closely related to Sinularia ceramensis and Sinularia peculiaris.

17.
Sci Total Environ ; 815: 152845, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-34990693

RESUMEN

The microplastic pollution has become a worldwide ecological concerns and imposed negative impacts on the coral reef ecosystems. In the present study, the distribution and characteristics of microplastics in the seawater, marine sediment and three scleractinian coral species (Pocillopora damicornis, Galaxea fascicularis, and Porites lutea) at five representative atolls in the Xisha Islands were investigated. The average microplastic abundances in the seawater and marine sediment were 9.5 ± 3.7 particles L-1 and 280.9 ± 231.9 particles kg-1 (dry weight), and the average contents of microplastics in P. damicornis, G. fascicularis and P. lutea were 0.9 ± 0.5 particles cm-2, 1.2 ± 0.6 particles cm-2, and 2.5 ± 1.6 particles cm-2, respectively. There were no significant correlations for the microplastic concentration between the reef environment and the corals. These results infer that the microplastic pollution is severe in the coral reef ecosystem in the Xisha Islands, and scleractinian corals could enrich microplastics from the reef environment. In addition, more than 80% of the microplastics in the seawater, marine sediment and corals were smaller than 2 mm, and the most common types of microplastics were cellophane (61.13%) and polyethylene terephthalate (33.49%). Black and fibers were the most common color and shape of the microplastics in the seawater and marine sediment, respectively. The microplastics in transparent color, film shape and small size (<2 mm) were highly accumulated in corals. Besides, cluster analysis showed that significant difference of microplastic characteristics existed between the corals and the reef environment, and the features of enriched microplastics among three coral species were also different. Moreover, P. lutea exhibited a stronger ability in enriching microplastics than G. fascicularis and P. damicornis. These results suggest that the microplastic-enriching capacities of scleractinian corals are species-specific, and species acclimated to microplastic pollution might become predominant in future coral community.


Asunto(s)
Antozoos , Contaminantes Químicos del Agua , Animales , Arrecifes de Coral , Ecosistema , Monitoreo del Ambiente , Islas , Microplásticos , Plásticos , Contaminantes Químicos del Agua/análisis
18.
Aquat Toxicol ; 243: 106075, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35033793

RESUMEN

Microplastics are emerging as widespread pollutants in coral reef ecosystems worldwide; however, there is limited knowledge regarding their impact on giant clams, which are important reef builders. In the present study, the cytological, physiological, and molecular response of the giant clam Tridacna crocea to a 5 d exposure of microplastics was investigated. The concentration of microplastics in the intestine and outer mantle increased significantly and gradually after the exposure to microplastics. There were no significant changes in the density of symbiotic Symbiodiniaceae throughout the exposure period, but symbiont chlorophyll content increased significantly after 1 d of exposure. There was a significant increase in symbiont superoxide dismutase (SOD) activity, but a decrease in giant clam SOD activity and symbiont glutathione S-transferase (GST) activity. No significant changes in catalase (CAT) activity and caspase3 activation level were observed in the two symbiotic partners. Transcriptomic analysis of the giant clam revealed 138 significantly upregulated and 1390 significantly downregulated genes after 5 d of microplastic exposure. The top 20 GO terms overrepresented by these significantly downregulated genes were related to primary metabolic processes and cellular metabolic processes. No significantly upregulated genes were observed in symbionts, but 28 genes were significantly downregulated, including chloroplast oxygen-evolving enhancer, photosystem I reaction center subunit II, peptide/nitrate transporter, sodium-coupled neutral amino acid transporter, beta-glucosidase, and TPA: lipase. These results suggest that T. crocea ingests microplastics through the outer mantle and intestine, and these microplastics can suppress the photosynthesis, organic nutrient transportation, and detoxification ability of the symbionts, as well as the primary metabolism of the giant clam. This eventually could threaten their metabolic relationship and long-term survival.


Asunto(s)
Bivalvos , Contaminantes Químicos del Agua , Animales , Ecosistema , Microplásticos , Transportadores de Nitrato , Plásticos , Contaminantes Químicos del Agua/toxicidad
19.
Front Plant Sci ; 13: 975251, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36518512

RESUMEN

Seagrass plays a vital role in the stability of marine ecology. The human development of marine resources has greatly affected the survival of seagrass. Seawater salinity is one of the important factors affecting its survival. Seagrass can survive in high saline environments for a long time and has evolved a variety of effective tolerance mechanisms. However, little is known about the molecular mechanisms underlying salinity tolerance by seagrass. Thalassia hemprichii is a seagrass species with a global distribution. It is also an ecologically important plant species in coastal waters. Nevertheless, the continuous environmental deterioration has gradually reduced the ecological niche of seagrasses. In this study, experiments were conducted to examine the effects of salinity changes on T. hemprichii. The result showed that the optimal salinity for T. hemprichii is 25 to 35 PSU. Although it can survive under high and low salinity, high mortality rates are common in such environments. Further analyses revealed that high salinity induces growth and developmental retardation in T. hemprichii and further causes yellowing. The parenchyma cells in T. hemprichii also collapse, the structure changes, soluble sugar accumulates rapidly, soluble proteins accumulate rapidly, the malondialdehyde (MDA) content reduces, and lipid peroxidation reduces in plant membranes. The molecular mechanisms of salt tolerance differ significantly between marine and terrestrial plants. We found 319 differentially expressed genes (DEGs). These genes regulate transport and metabolism, promoting environmental adaptation. The expression of these genes changed rapidly upon exposure of T. hemprichii to salinity stress for three hours. This is the first report on the physiological and biochemical changes and gene expression regulation of T. hemprichii under different salinity conditions. The findings of this study well deepen our understanding of T. hemprichii adaptations to changes in the shoal living environment.

20.
J Hazard Mater ; 404(Pt B): 124205, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-33086184

RESUMEN

Microplastics are emerging contaminants and widespread in the ocean, but their impacts on coral reef ecosystems are poorly understood, and in situ study is still lacking. In the present study, the distribution patterns of microplastics in the environment and inhabiting organisms were investigated along the east coast of Hainan Island, South China Sea, and the physiological impacts of the microplastics on scleractinian corals were analyzed. We documented average microplastic concentrations of 14.90 particlesL-1 in seawater, 343.04 particleskg-1 in sediment, 4.97 particlescm-2 in corals, and 0.67-3.12 particlescm-1 in Tridacnidae, Trochidae and fish intestines. Further analysis revealed that the characteristics of microplastics in the organisms were different from those in the environment, indicating preferential enrichment in the organisms. Furthermore, there was an obvious correlation between microplastic concentration and symbiotic density in corals. Furthermore, caspase3 activity was significantly positively correlated with the microplastic content in the small-polyp coral Pocillopora damicornis, but the large-polyp coral Galaxea fascicularis showed higher tolerance to microplastics. Taken together, our results suggest that microplastics are selectively enriched in corals and other reef-dwellers, in which they exact differential stress (apoptotic) effects, with the potential to impact the coral-Symbiodiniaceae symbiosis and alter the coral community structure.


Asunto(s)
Antozoos , Contaminantes Químicos del Agua , Animales , China , Ecosistema , Microplásticos , Plásticos/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
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