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Nanoplastics (NPs) and polycyclic aromatic hydrocarbons (PAHs) are recognized as persistent organic pollutant (POPs) with demonstrated physiological toxicity. When present in aquatic environments, the two pollutants could combine with each other, resulting in cumulative toxicity to organisms. However, the combined impact of NPs and PAHs on microorganisms in seawater is not well understood. In this study, we conducted an exposure experiment to investigate the individual and synergistic effects of NPs and PAHs on the composition, biodiversity, co-occurrence networks of microbial communities in seawater. Exposure of individuals to PAHs led to a reduction in microbial community richness, but an increase in the relative abundance of species linked to PAHs degradation. These PAHs-degradation bacteria acting as keystone species, maintained a microbial network complexity similar to that of the control treatment. Exposure to individual NPs resulted in a reduction in the complexity of microbial networks. Furthermore, when PAHs and NPs were simultaneously present, the toxic effect of NPs hindered the presence of keystone species involved in PAHs degradation, subsequently limiting the degradation of PAHs by marine microorganisms, resulting in a decrease in community diversity and symbiotic network complexity. This situation potentially poses a heightened threat to the ecological stability of marine ecosystems. Our work strengthened the understanding of the combined impact of NPs and PAHs on microorganisms in seawater.
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Microbiota , Hidrocarburos Policíclicos Aromáticos , Agua de Mar , Contaminantes Químicos del Agua , Hidrocarburos Policíclicos Aromáticos/toxicidad , Hidrocarburos Policíclicos Aromáticos/análisis , Agua de Mar/química , Agua de Mar/microbiología , Contaminantes Químicos del Agua/toxicidad , Microbiota/efectos de los fármacos , Bacterias/efectos de los fármacos , Microbiología del Agua , Microplásticos/toxicidad , Biodiversidad , Monitoreo del AmbienteRESUMEN
In order to study the dynamics of marine phytoplankton communities in response to anticipated in temperature and CO2, a shipboard continuous culture experiment (Ecostat) was conducted. The experiment involved simulations under current atmospheric CO2 concentrations (400 ppm) and projected year-2100 CO2 levels (1000 ppm), as well as varying temperature under present (22 °C) versus increased temperature (26 °C) in the Yellow Sea during the summer of 2020. The results showed that both the increased pCO2 and temperature had significant effects on microphytoplankton and picophytoplankton, with the warming effect proving to be more significant. The different responses of various species to acidification and warming and their coupling effect led to the changes in microphytoplankton and picophytoplankton community structure. Elevated temperature and greenhouse treatments promoted the growth of dominant diatoms and Synechococcus, such as Guinardia flaccida and Pseudo-nitzschia delicatissima. This phenomenons widened the ecological niche, and the changes in the growth patterns of dominant species consequently influenced the content of cellular elements. Mantel's analysis further demonstrated that both warming and greenhouse promoted the growth of diatoms and Synechococcus. Projections of marine phytoplankton community trends by the end of the century based on Growth Rate Ratio (GRR), indicated that not only would species with GRR < 1 decrease, but also numerous species with growth rates >1 at elevated pCO2 levels would be ousted from competition. This experiment demonstrates the need to investigate whether extended exposure to increased pCO2 and temperature over more extended time scales would similarly induce shifts in the biological and biogeochemical dynamics of the Yellow Sea.
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Diatomeas , Fitoplancton , Fitoplancton/fisiología , Temperatura , Dióxido de Carbono , Diatomeas/fisiología , Ecosistema , Agua de Mar/químicaRESUMEN
Since the coronavirus disease 2019 (COVID-19) epidemic, insomnia has become one of the longer COVID-19 symptoms. This study aimed to investigate insomnia among COVID-19 survivors and explore the occurrence and influencing factors of insomnia. A cross-sectional study was performed from December 2022 to February 2023 through an online questionnaire star survey with 8 questions. The insomnia severity index scale (ISI) was used to assess the severity of insomnia. Univariate analysis was used to analyze the factors related to COVID-19 infection. A total of 564 participants (183 males and 381 females) were surveyed in the present study. The prevalence of insomnia was 63.12%. Among these insomnia patients, there were 202 (35.82%) with sub-threshold symptoms, 116 (20.57%) with moderate symptoms, and 38 (6.74%) with severe symptoms. Univariate analysis indicated that there were statistically significant differences in the prevalence of insomnia among COVID-19 survivors of different ages, occupations, and educational levels (Pâ <â .05). Of the 356 insomnia patients, 185 (51.97%) did not take any measures against insomnia, while those who took drugs only, physical exercise only, drugs and physical exercise, and other measures were 90 (25.28%), 42 (11.80%), 17 (4.78%), and 22 (6.18%), respectively. Additionally, of the 107 insomnia patients with drug therapy, 17 (15.89%) took estazolam, 16 (14.95%) took alprazolam, 39 (36.45%) took zopiclone, and 35 (32.71%) took other drugs to improve insomnia symptoms. The prevalence of insomnia symptoms remains high among COVID-19 survivors in China. Education level and occupation may be the influencing factors. Unfortunately, most patients with insomnia do not take corresponding treatment measures.
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COVID-19 , Trastornos del Inicio y del Mantenimiento del Sueño , Masculino , Femenino , Humanos , COVID-19/epidemiología , Estudios Transversales , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , SARS-CoV-2 , Ansiedad/epidemiología , Depresión/epidemiologíaRESUMEN
Heavy metal contamination has been the focus of many studies owing to its potential risk on the health of coastal ecosystems. The Bohai Bay (BHB) is the second largest bay of Bohai Sea and subjected to serious anthropogenic perturbations. The aim of this study was to evaluate the distribution and pollution status of toxic heavy metals in seawater with two fractions (dissolved and suspended particulate phases) and surface sediments of this coastal system. Therefore, several hydrochemical parameters and concentration of seawater metals and sediment metals were measured at two cruises of 2020 summer and autumn. The spatial distribution and potential ecological risks were examined and their inter-element relationships were analyzed to identify potential geochemical processes. By comparing historical data since 1978, we find declining trends in contents of most trace metals in seawater and sediments, suggesting that recent pollution control in BHB have an effect on diminishing metal pollution. Dissolved metals showed no significant dependence on their particulate phase. The seawater posed a moderate to high level of ecological risk. The hydrochemical factors mainly had a greater impact on dissolved metals during summer, whereas they influenced suspended metals more significantly during autumn. These results provide fundamental information to support environmental quality management and ecological protection in coastal systems.
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Metales Pesados , Contaminantes Químicos del Agua , Sedimentos Geológicos/química , Bahías/química , Ecosistema , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Agua de Mar/química , Metales Pesados/análisis , China , Medición de RiesgoRESUMEN
Ocean warming and acidification interactively affect the coccolithophore physiology and drives major biogeochemical changes. While numerous studies investigated coccolithophore under short-term conditions, knowledge on how different transitional periods over long-exposure could influence the element, macromolecular and metabolic changes for its acclimation are largely unknown. We cultured the coccolithophore Chrysotila dentata, (culture generations of 1st, 10th, and 20th) under present (low-temperature low-carbon-dioxide [LTLC]) and projected (high-temperature high-carbon-dioxide [HTHC]) ocean conditions. We examined elemental and macromolecular component changes and sequenced a transcriptome. We found that with long-exposure, most physiological responses in HTHC cells decreased when compared with those in LTLC, however, HTHC cell physiology showed constant elevation between each generation. Specifically, compared to 1st generation, the 20th generation HTHC cells showed increases in quota carbon (Qc:29%), nitrogen (QN :101%), and subsequent changes in C:N-ratio (68%). We observed higher lipid accumulation than carbohydrates within HTHC cells under long-exposure, suggesting that lipids were used as an alternative energy source for cellular acclimation. Protein biosynthesis pathways increased their efficiency during long-term HTHC condition, indicating that cells produced more proteins than required to initiate acclimation. Our findings suggest that the coccolithophore resilience increased between the 1st-10th generation to initiate the acclimation process under ocean warming and acidifying conditions.
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Aclimatación , Carbono , Concentración de Iones de Hidrógeno , Aclimatación/fisiología , Carbono/metabolismo , Temperatura , Océanos y Mares , Agua de Mar/química , Dióxido de Carbono/análisisRESUMEN
UCYN-A is one of the most widespread and important marine diazotrophs. Its unusual distribution in both cold/warm and coastal/oceanic waters challenges current understanding about what drives the biogeography of diazotrophs. This study assessed the community assembly processes of the nitrogen-fixing cyanobacterium UCYN-A, developing a framework of assembly processes underpinning the microbial biogeography and diversity. High-throughput sequencing and a qPCR approach targeting the nifH gene were used to investigate three tropical seas: the Bay of Bengal, the Western Pacific Ocean, and the South China Sea. Based on the neutral community model and two types of null models calculating the ß-nearest taxon index and the normalized stochasticity ratio, we found that stochastic assembly processes could explain 66-92% of the community assembly; thus, they exert overwhelming influence on UCYN-A biogeography and diversity. Among the deterministic processes, temperature and coastal/oceanic position appeared to be the principal environmental factors driving UCYN-A diversity. In addition, a close linkage between assembly processes and UCYN-A abundance/diversity/drivers can provide clues for the unusual global distribution of UCYN-A.
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The variation of diazotrophs has been elusive in multiple SCS and WPO regions due to insufficient data. Therefore, the dynamics of diazotrophic composition and distribution were investigated in this study, based on high-throughput sequencing and quantitative PCR of the nifH gene. We found that Proteobacteria dominated the diazotrophic community in the river-impacted SCS and cyanobacteria and Proteobacteria were more abundant in the ocean-dominated SCS and WPO. The qPCR analysis showed that cyanobacterial Trichodesmium was abundant in the Pearl River plume and in the SCS basin influenced by the Kuroshio intrusion, and it also thrived in the subequatorial region of the WPO. Unicellular cyanobacteria UCYN-A were mainly detected in the river-impacted area, UCYN-B was abundant in the WPO, UCYN-C had a relatively high abundance in the ocean-dominated area, and a preponderance of γ-Proteobacteria γ-24774A11 was observed in the ocean-dominated SCS and pelagic WPO. Diazotrophic communities had significant distance-decay relationships, reflecting clear biogeographic patterns in the study area. The variations of diazotrophic community structure were well explained by dissolved inorganic nitrogen, dissolved inorganic phosphate by an eigenvector spatial variable PCNM1. These results provide further information to help determine the ecological mechanism of elusive diazotrophic communities in different ocean ecosystems.
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Currently, there is scant information about the biodiversity and functional diversity of microbes in the eastern Indian Ocean (EIO). Here, we used a combination of high-throughput sequencing of 16S rRNA genes and a metagenomic approach to investigate the microbial population structure and its metabolic function in the equatorial EIO. Our results show that Cyanobacterial Prochlorococcus made up the majority of the population. Interestingly, there were fewer contributions from clades SAR11 (Alphaproteobacteria) and SAR86 (Gammaproteobacteria) to microbial communities than contributions from Prochlorococcus. Based on functional gene analysis, functional genes rbcL, narB, and nasA were relatively abundant among the relevant genes. The abundance of Prochlorococcus implies its typically ecological adaptation in the local ecosystem. The microbial metabolic potential shows that in addition to the main carbon fixation pathway Calvin cycle, the rTCA cycle and the 3-HP/4-HB cycle have potential alternative carbon fixation contributions to local ecosystems. For the nitrogen cycle, the assimilatory nitrate and nitrite reduction pathway is potentially the crucial form of nitrogen utilization; unexpectedly, nitrogen fixation activity was relatively weak. This study extends our knowledge of the roles of microbes in energy and resource cycling in the EIO and provides a foundation for revealing profound biogeochemical processes driven by the microbial community in the ocean.
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Marine chromophytic phytoplankton are a diverse group of algae and contribute significantly to the total oceanic primary production. However, the spatial distribution of chromophytic phytoplankton is understudied in the West Pacific Ocean (WPO). In this study, we have investigated the community structure and spatial distribution of chromophytic phytoplankton using RuBisCO genes (Form ID rbcL). Our results showed that Haptophyceae, Pelagophyceae, Cyanophyceae, Xanthophyceae, and Bacillariophyceae were the dominant groups. Further, chromophytic phytoplankton can be distinguished between upwelling and non-upwelling zones of the WPO. Surface and 75 m depths of a non-upwelling area were dominated by Prochlorococcus strains, whereas chromophytic phytoplankton were homogenously distributed at the surface layer in the upwelling zone. Meanwhile, Pelagomonas-like sequences were dominant at DCM (75 m) and 150 m depths of the upwelling zone. Non-metric multidimensional scaling (NMDS) analysis did not differentiate between chromophytic phytoplankton in the upwelling and non-upwelling areas, however, it showed clear trends of them at different depths. Further, redundancy analysis (RDA) showed the influence of physicochemical parameters on the distribution of chromophytic phytoplankton. Along with phosphate (p < 0.01), temperature and other dissolved nutrients were important in driving community structure. The upwelling zone was impacted by a decrease in temperature, salinity, and re-supplement of nutrients, where Pelagomonas-like sequences outnumbered other chromophytic groups presented.
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Astaxanthin (ATX), which is the most abundant flavonoid in propolis, has previously shown neuroprotective properties against cerebral ischaemia-induced apoptosis. However, the mechanisms by which ATX mediates its therapeutic effects are unclear. At present, we explored the underlying mechanisms involved in the protective effects of ATX via the phosphoinositide 3-kinase (PI3K)/Akt/glycogen synthase kinase 3 beta (GSK3ß)/nuclear factor erythroid 2-related factor 2 (Nrf2) signalling pathway in SH-SY5Y cells. The PI3K/Akt inhibitor LY294002 and GSK3ß inhibitor LiCl were employed in this study. Pre-treatment with ATX for 24 hours significantly decreased the oxygen and glucose deprivation (OGD)-induced viability loss, reduced the proportion of apoptosis and regulated OGD-mediated reactive oxygen species (ROS) production. Furthermore, ATX suppressed OGD-caused mitochondrial membrane potential and decomposition of caspase-3 to cleaved caspase-3, and heightened the B-cell lymphoma 2 (Bcl-2)/Bax ratio. PI3K/Akt/GSK3ß/Nrf2 signalling pathway activation in SH-SY5Y cells was verified by Western blot. ATX and LiCl treatment raised the protein levels of p-Akt, p-GSK3ß, nucleus Nrf2 and haeme oxygenase 1 (HO-1). However, these protein expression levels decreased by treatment of LY294002. The above in vitro data indicate that ATX can confer neuroprotection against OGD-induced apoptosis via the PI3K/Akt/GSK3ß/Nrf2 signalling pathway.
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Glucosa/metabolismo , Fármacos Neuroprotectores/farmacología , Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Línea Celular Tumoral , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Hemo-Oxigenasa 1/metabolismo , Humanos , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Xantófilas/farmacologíaRESUMEN
Picophytoplankton were investigated during spring 2015 and 2016 extending from near-shore coastal waters to oligotrophic open waters in the eastern Indian Ocean (EIO). They were typically composed of Prochlorococcus (Pro), Synechococcus (Syn), and picoeukaryotes (PEuks). Pro dominated most regions of the entire EIO and were approximately 1-2 orders of magnitude more abundant than Syn and PEuks. Under the influence of physicochemical conditions induced by annual variations of circulations and water masses, no coherent abundance and horizontal distributions of picophytoplankton were observed between spring 2015 and 2016. Although previous studies reported the limited effects of nutrients and heavy metals around coastal waters or upwelling zones could constrain Pro growth, Pro abundance showed strong positive correlation with nutrients, indicating the increase in nutrient availability particularly in the oligotrophic EIO could appreciably elevate their abundance. The exceptional appearance of picophytoplankton with high abundance along the equator appeared to be associated with the advection processes supported by the Wyrtki jets. For vertical patterns of picophytoplankton, a simple conceptual model was built based upon physicochemical parameters. However, Pro and PEuks simultaneously formed a subsurface maximum, while Syn generally restricted to the upper waters, significantly correlating with the combined effects of temperature, light, and nutrient availability. The average chlorophyll a concentrations (Chl a) of picophytoplankton accounted for above 49.6% and 44.9% of the total Chl a during both years, respectively, suggesting that picophytoplankton contributed a significant proportion of the phytoplankton community in the whole EIO.
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It has been reported that cornin may reduce neuronal death during cerebral ischemia; however, little is known about the molecular mechanism of the role of corninin autophagy in SHSY5Y neuronal cells. In the present study, oxygenglucose deprivation (OGD)treated cells were used as a cerebral ischemia model in vitro. The results demonstrated that cornin was able to reduce neuronal cell loss, increase the apoptosis regulator Bcl2/apoptosis regulator BAX ratio, and decrease the protein levels of caspase3. In addition, cornin decreased the microtubuleassociated proteins 1A/1B light chain 3B (LC3)II/LC3I ratio and beclin1 protein expression, and resulted in an upregulation in phosphorylated (p)RACα serine/threonineprotein kinase (Akt), pprotein kinase mTOR (mTOR) in OGDtreated SHSY5Y cells. Additionally, it was observed that following inhibition of PI3K/Akt by LY294002, the levels of pAkt and pmTOR were markedly decreased, and the LC3II/LC3I ratio and beclin1 were increased. Similarly, following inhibition of mTOR by rapamycin, LC3II/LC3I and Beclin1 were significantly increased in SHSY5Y cells. These results indicated that cornin protected SHSY5Y cells against OGDinduced autophagy through the PI3K/Akt/mTOR pathway.
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Mezclas Complejas/farmacología , Glucosa/metabolismo , Oxígeno/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Autofagia/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , HumanosRESUMEN
Predatory bacteria are ubiquitously distributed in nature in including in aquatic environments, sewage, intestinal tracts of animals and humans, rhizophere and, soils. However, our understanding of their evolutionary history is limited. Results of recent studies have shown that acquiring novel genes is a major force driving bacterial evolution. Therefore, to gain a better understanding of the impact of gene gain and loss in the evolution of bacterial predators, this study employed comparative genomic approaches to identify core-set gene families and species-specific gene families, and model gene gain and loss events among 11 genomes that represented diverse lineages. In total, 1977 gene families were classified. Of these 509 (pattern 11111111111) were present all of the 11 species. Among the non-core set gene families, 52 were present only in saltwater bacteria predators and had no ortholog in the other genomes. Similarly 109 and 44 were present only in the genomes of Micavibrio spp. and Bdellovibrio spp., respectively. In this study, the gain loss mapping engine GLOOME was selected to analyze and estimate the expectations and probabilities of both gain and loss events in the predatory bacteria. In total, 354 gene families were involved in significant gene gain events, and 407 gene families were classified into gene loss events with high supported value. Moreover, 18 families from the core set gene family were identified as putative genes under positive selection. The results of this study suggest that acquisition of particular genes that encode functional proteins in metabolism and cellular processes and signaling, especially ABC systems, may help bacterial predators adapt to surrounding environmental changes and present different predation strategies for survival in their habitats.
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Bacterias/genética , Bacterias/patogenicidad , Evolución Molecular , Genes Bacterianos , Alphaproteobacteria/clasificación , Alphaproteobacteria/genética , Alphaproteobacteria/patogenicidad , Animales , Bacterias/clasificación , Bacteroidetes/clasificación , Bacteroidetes/genética , Bacteroidetes/patogenicidad , Bdellovibrio/clasificación , Bdellovibrio/genética , Bdellovibrio/patogenicidad , Mapeo Cromosómico , Deltaproteobacteria/clasificación , Deltaproteobacteria/genética , Deltaproteobacteria/patogenicidad , Ecosistema , Humanos , Familia de Multigenes , Filogenia , Virulencia/genéticaRESUMEN
The development of multidrug resistance (MDR) is a crucial cause of therapy failure in gastric cancer, which results in disease recurrence and metastasis. Long non-coding RNAs (lncRNAs) have been proven to be critical in carcinogenesis and metastasis of gastric cancer. However, little is known about the roles of ANRIL (antisense non-coding RNA in the INK4 locus) in gastric cancer MDR. The aim of our study is to identify the biological function of ANRIL in gastric cancer MDR. In our results, ANRIL was highly expressed in gastric cancer tissues of cisplatin-resistant and 5-fluorouracil (5-FU)-resistant patients, and the same upregulation trends were observed in cisplatin-resistant cells (BGC823/DDP) and 5-FU-resistant cells (BGC823/5-FU). In addition, BGC823/DDP and BGC823/5-FU cells transfected with ANRIL siRNA and treated with cisplatin or 5-FU, respectively, exhibited significant lower survival rate, decreased invasion capability, and high percentage of apoptotic tumor cells. The influence of ANRIL knockdown on MDR was assessed by measuring IC50 of BGC823/DDP and BGC823/5-FU cells to cisplatin and 5-FU, the result showed that silencing ANRIL decreased the IC50 values in gastric cancer cells. Moreover, qRT-PCR and western blotting revealed that ANRIL knockdown decreased the expression of MDR1 and MRP1, both of which are MDR related genes; regression analysis showed that the expression of ANRIL positively correlated with the expression of MDR1 and MRP1, resprectively In summary, knockdown of lncRNA ANRIL in gastric cancer cells inhibits the development of MDR, suggesting an efficacious target for reversing MDR in gastric cancer therapy.
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Resistencia a Múltiples Medicamentos/genética , Resistencia a Antineoplásicos/genética , Silenciador del Gen/fisiología , ARN Largo no Codificante/genética , Neoplasias Gástricas/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/genética , Línea Celular Tumoral , Cisplatino/administración & dosificación , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Fluorouracilo/administración & dosificación , Silenciador del Gen/efectos de los fármacos , Humanos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Recurrencia Local de Neoplasia/genética , ARN Interferente Pequeño , Estómago/efectos de los fármacos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/patología , Tasa de Supervivencia , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/genéticaRESUMEN
OBJECTIVE: To investigate the changes in the number and distribution of myoepithelial cells during atrophy of the rat parotid gland. METHODS: Atrophy of the right parotid was induced by ligating the right stensen duct of rats, histological changes of parotid glands were examined by hematoxylin-eosin (HE) staining during each step of glandular atrophy at the time of 0 (control), 1, 3, 5, 7, 14, 21, 30, 60, 100, and 150 days after ligation. Immunohistochemical labelling was performed to study the changes in number and distribution of myoepithelial cells during atrophy of the rat parotid gland. RESULTS: Histological analysis showed disappearance of the acini at 5 d and gradual decrease and fibrosis of the glandular lobules accompanied by the occurrence of duct-like structures. Quantitative analysis of myoepithelial cells showed significant increase in number up to day 5 after ligation, then followed by gradual increases at a low level, at last it was followed by a rapid decrease after the total number reached the peak in 100 days. In addition, the acini and intercalated ducts were covered by myoepithelial cells ranged from the shape of spindle to stellate during the early phase of atrophy, while spindle-shaped myoepithelial cells were located at the periphery of duct-like structures in the later phase of atrophy. CONCLUSION: Myoepithelial cells proliferated rapidly up to day 5 after ligation, then followed by gradual increase at a low level, at last it was followed by a rapid decrease after the total number reached the peak in 100 days.