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1.
Environ Sci Technol ; 58(9): 4392-4403, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38362876

RESUMEN

Unraveling the mysterious pathways of pollutants to the deepest oceanic realms holds critical importance for assessing the integrity of remote marine ecosystems. This study tracks the transport of pollutants into the depths of the oceans, a key step in protecting the sanctity of these least explored ecosystems. By analyzing hadal trench samples from the Mariana, Mussau, and New Britain trenches, we found the widespread distribution of organophosphate ester (OPE) flame retardants but a complex transport pattern for the OPE in these regions. In the Mariana Trench seawater column, OPE concentrations range between 17.4 and 102 ng L-1, with peaks at depths of 500 and 4000 m, which may be linked to Equatorial Undercurrent and topographic Rossby waves, respectively. Sediments, particularly in Mariana (422 ng g-1 dw), showed high OPE affinity, likely due to organic matter serving as a transport medium, influenced by "solvent switching", "solvent depletion", and "filtering processes". Amphipods in the three trenches had consistent OPE levels (29.1-215 ng g-1 lipid weight), independent of the sediment pollution patterns. The OPEs in these amphipods appeared more linked to surface-dwelling organisms, suggesting the influence of "solvent depletion". This study highlights the need for an improved understanding of deep-sea pollutant sources and transport, urging the establishment of protective measures for these remote marine habitats.


Asunto(s)
Anfípodos , Contaminantes Ambientales , Retardadores de Llama , Animales , Ecosistema , Organofosfatos , Ésteres , Solventes
2.
J Fish Biol ; 104(3): 887-891, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37933516

RESUMEN

This note reports on eight observations of inverted swimming behavior by species of ceratioid whipnose anglerfishes in the genus Gigantactis, from the Caribbean, tropical east Atlantic, tropical western Indian Ocean, the north-east and north-west Pacific and south-west Pacific. It covers four putative species and strongly suggests that this is the normal behavior for the genus. A possible reason is briefly discussed. In addition, a new depth record of 5866 m for the ceratioid anglerfish is recorded.


Asunto(s)
Peces , Natación , Animales , Océano Índico , Región del Caribe , Océano Pacífico
3.
Environ Sci Technol ; 57(16): 6550-6562, 2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-37042785

RESUMEN

Deep oceans receive mercury (Hg) from upper oceans, sediment diagenesis, and submarine volcanism; meanwhile, sinking particles shuttle Hg to marine sediments. Recent studies showed that Hg in the trench fauna mostly originated from monomethylmercury (MMHg) of the upper marine photosynthetic food webs. Yet, Hg sources in the deep-sea chemosynthetic food webs are still uncertain. Here, we report Hg concentrations and stable isotopic compositions of indigenous biota living at hydrothermal fields of the Indian Ocean Ridge and a cold seep of the South China Sea along with hydrothermal sulfide deposits. We find that Hg is highly enriched in hydrothermal sulfides, which correlated with varying Hg concentrations in inhabited biota. Both the hydrothermal and cold seep biota have small fractions (<10%) of Hg as MMHg and slightly positive Δ199Hg values. These Δ199Hg values are slightly higher than those in near-field sulfides but are 1 order of magnitude lower than the trench counterparts. We suggest that deep-sea chemosynthetic food webs mainly assimilate Hg from ambient seawater/sediments and hydrothermal fluids formed by percolated seawater through magmatic/mantle rocks. The MMHg transfer from photosynthetic to chemosynthetic food webs is likely limited. The contrasting Hg sources between chemosynthetic and trench food webs highlight Hg isotopes as promising tools to trace the deep-sea Hg biogeochemical cycle.


Asunto(s)
Mercurio , Contaminantes Químicos del Agua , Isótopos de Mercurio/análisis , Cadena Alimentaria , Monitoreo del Ambiente , Mercurio/análisis , Isótopos , Océano Índico , Biota , Contaminantes Químicos del Agua/análisis
4.
Macromol Rapid Commun ; 40(16): e1900234, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31210405

RESUMEN

The design and development of photoinitiating systems applicable to UV or even visible light delivered from light-emitting diodes (LEDs) has been attracting increasing attention due to their great potential applications in various fields. Compared to the strategy of synthesizing novel compounds, the exploration of existing chemicals with interesting photochemical/photophysical properties for their usage as photoinitiators is more appealing and easily commercialized. Nevertheless, a number of compounds such as monoamino-substituted anthraquinone derivatives, which are intensively investigated for their photophysical and photochemical properties, have seldom been studied for their roles as photoinitiators under LED irradiation. Herein, three monoamino-substituted anthraquinone derivatives, that is, 1-aminoanthraquinone, 1-(methylamino)anthraquinone and 1-(benzamido)anthraquinone, are studied for their potential as photoinitiators. The photoinitiation mechanism of these monoamino-substituted anthraquinone derivatives, when combined with iodonium salt, is first clarified using computational quantum chemistry, fluorescence, steady-state photolysis, and electron spin resonance spin-trapping techniques. Then, their photoinitiation ability for the cationic photopolymerization of epoxide and divinyl ether monomers is also investigated.


Asunto(s)
Antraquinonas/química , Luz , Antraquinonas/síntesis química , Cationes/síntesis química , Cationes/química , Estructura Molecular , Procesos Fotoquímicos , Polimerizacion
5.
World J Surg Oncol ; 16(1): 22, 2018 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-29394946

RESUMEN

BACKGROUND: To examine the clinical value of miR-198-5p in lung squamous cell carcinoma (LUSC). METHODS: Gene Expression Omnibus (GEO) microarray datasets were used to explore the miR-198-5p expression and its diagnostic value in LUSC. Real-time reverse transcription quantitative polymerase chain reaction was used to evaluate the expression of miR-198-5p in 23 formalin-fixed, paraffin-embedded (FFPE) LUSC tissues and corresponding non-cancerous tissues. The correlation between miR-198-5p expression and clinic pathological features was assessed. Meanwhile, putative target messenger RNAs of miR-198-5p were identified based on the analysis of differentially expressed genes in the Cancer Genome Atlas (TCGA) and 12 miRNA prediction tools. Subsequently, the putative target genes were sent to Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses. RESULTS: MiR-198-5p was low expressed in LUSC tissues. The combined standard mean difference (SMD) values of miR-198-5p expression based on GEO datasets were - 0.30 (95% confidence interval (CI) - 0.54, - 0.06) and - 0.39 (95% CI - 0.83, 0.05) using fixed effect model and random effect model, respectively. The sensitivity and specificity were not sufficiently high, as the area under the curve (AUC) was 0.7749 (Q* = 0.7143) based on summarized receiver operating characteristic (SROC) curves constructed using GEO datasets. Based on the in-house RT-qPCR, miR-198-5p expression was 4.3826 ± 1.7660 in LUSC tissues and 4.4522 ± 1.8263 in adjacent normal tissues (P = 0.885). The expression of miR-198-5p was significantly higher in patients with early TNM stages (I-II) than that in cases with advanced TNM stages (III-IV) (5.4400 ± 1.5277 vs 3.5690 ± 1.5228, P = 0.008). Continuous variable-based meta-analysis of GEO and PCR data displayed the SMD values of - 0.26 (95% CI - 0.48, - 0.04) and - 0.34 (95% CI - 0.71, 0.04) based on fixed and random effect models, respectively. As for the diagnostic value of miR-198-5p, the AUC based on the SROC curve using GEO and PCR data was 0.7351 (Q* = 0.6812). In total, 542 genes were identified as the targets of miR-198-5p. The most enriched Gene Ontology terms were epidermis development among biological processes, cell junction among cellular components, and protein dimerization activity among molecule functions. The pathway of non-small cell lung cancer was the most significant pathway identified using Kyoto Encyclopedia of Genes and Genomes analysis. CONCLUSION: The expression of miR-198-5p is related to the TNM stage. Thus, miR-198-5p might play an important role via its target genes in LUSC.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Células Escamosas/genética , Perfilación de la Expresión Génica , Neoplasias Pulmonares/genética , MicroARNs/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Escamosas/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Ontología de Genes , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Pronóstico , Curva ROC
6.
Appl Microbiol Biotechnol ; 99(20): 8751-64, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26078113

RESUMEN

Successful bioremediation of oil pollution is based on a comprehensive understanding of the in situ physicochemical conditions and indigenous microbial communities as well as the interaction between microorganisms and geochemical variables. Nineteen oil-contaminated soil samples and five uncontaminated controls were taken from six major oilfields across different geoclimatic regions in China to investigate the spatial distribution of the microbial ecosystem. Microbial community analysis revealed remarkable variation in microbial diversity between oil-contaminated soils taken from different oilfields. Canonical correspondence analysis (CCA) further demonstrated that a suite of in situ geochemical parameters, including soil moisture and sulfate concentrations, were among the factors that influenced the overall microbial community structure and composition. Phylogenetic analysis indicated that the vast majority of sequences were related to the genera Arthrobacter, Dietzia, Pseudomonas, Rhodococcus, and Marinobacter, many of which contain known oil-degrading or oil-emulsifying species. Remarkably, a number of archaeal genera including Halalkalicoccus, Natronomonas, Haloterrigena, and Natrinema were found in relatively high abundance in some of the oil-contaminated soil samples, indicating that these Euryarchaeota may play an important ecological role in some oil-contaminated soils. This study offers a direct and reliable reference of the diversity of the microbial community in various oil-contaminated soils and may influence strategies for in situ bioremediation of oil pollution.


Asunto(s)
Archaea/clasificación , Bacterias/clasificación , Biodegradación Ambiental , Biota , Yacimiento de Petróleo y Gas , Contaminación por Petróleo , Microbiología del Suelo , Archaea/genética , Archaea/aislamiento & purificación , Bacterias/genética , Bacterias/aislamiento & purificación , China , Análisis por Conglomerados , ADN de Archaea/química , ADN de Archaea/genética , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Genes de ARNr , Datos de Secuencia Molecular , ARN de Archaea/genética , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico
7.
Environ Microbiol ; 16(11): 3533-47, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24934726

RESUMEN

A group of black shale samples, which were collected sequentially along a continuous depositional unit from bottom fresh zone toward the surface regolith of the weathering profile at Chengkou County, Southwest China, were examined using mineralogical, geochemical and pyrosequencing techniques. The mineralogical and geochemical analyses indicated that the black shale profile provided a series of extremely acidic and chemical species that changed microbial habitats following the process of weathering. This finding is in contrast with a previous hypothesis that a low-diversity bacterial community existed in these harsh environments; the pyrosequencing analyses showed extremely diverse microbial communities with 33 different phyla/groups in these samples. Among these phyla/groups, proteobacteria, actinobacteria and firmcutes were more dominant than other phyla, and the phylogenetic structures of the bacterial communities vary with the progressive process of weathering. Moreover, the canonical-correlation analysis suggested that pH and sulfur in sulfate, followed by total Fe and sulfur in pyrite, are the significant factors that shape the microbial community structure. In addition, a large proportion of S- and Fe-related bacteria, such as Acidithiobacillus, Sulfobacillus, Thiobacillus, Ferrimicrobium and Ferrithrix, may be responsible for pyrite bio-oxidation, as well as for S and Fe biogeochemical cycling, in the black shale weathering environments.


Asunto(s)
Bacterias/metabolismo , Hierro/metabolismo , Minerales/química , Azufre/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Biodiversidad , Ecosistema , Ambiente , Filogenia
8.
Adv Mater ; : e2400178, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38843462

RESUMEN

The incorporation of functionalized nanofillers into polymers via photopolymerization approach has gained significant attention in recent years due to the unique properties of the resulting composite materials. Surface modification of nanofillers plays a crucial role in their compatibility and polymerization behavior within the polymer matrix during photopolymerization. This review focuses on the recent developments in surface modification of various nanofillers, enabling their integration into polymer systems through photopolymerization. The review discusses the key aspects of surface modification of nanofillers, including the selection of suitable surface modifiers, such as photoinitiators and polymerizable groups, as well as the optimization of modification conditions to achieve desired surface properties. The influence of surface modification on the interfacial interactions between nanofillers and the polymer matrix is also explored, as it directly impacts the final properties of the nanocomposites. Furthermore, the review highlights the applications of nanocomposites prepared by photopolymerization, such as sensors, gas separation membranes, purification systems, optical devices, and biomedical materials. By providing a comprehensive overview of the surface modification strategies and their impact on the photopolymerization process and the resulting nanocomposite properties, this review aims to inspire new research directions and innovative ideas in the development of high-performance polymer nanocomposites for diverse applications.

9.
Water Res ; 251: 121126, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38237461

RESUMEN

The "V"-shaped structure of hadal trenches acts as a natural collector of organic pollutants, drawing attention to the need for extensive research in these areas. Our review identifies significant concentrations of organic pollutants, including persistent organic pollutants, black carbon, antibiotic-resistant genes, and plastics, which often match those in industrialized regions. They may trace back to both human activities and natural sources, underscoring the trenches' critical role in ocean biogeochemical cycles. We highlight the complex lateral and vertical transport mechanisms within these zones. Advanced methodologies, including stable isotope analysis, biomarker identification, and chiral analysis within isotope-based mixing models, are crucial for discerning the origins and pathways of these pollutants. In forthcoming studies, we aim to explore advanced methods for precise pollutant tracing, develop predictive models to forecast the future distribution and impacts of pollutants in hadal zones and on the Earth's larger ecological systems.


Asunto(s)
Contaminantes Ambientales , Humanos , Ecosistema , Plásticos , Isótopos
10.
Life Sci ; 341: 122490, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38336274

RESUMEN

AIMS: The "Warburg effect" has been developed from the discovery that hypoxia-inducible factor 1α (HIF-1α) could promote the conversion of pyruvate to lactate. However, no studies have linked hypoxia and lactate metabolism to uterine corpus endometrial carcinoma (UCEC). MAIN METHODS: Sequencing and clinical data of patients with UCEC were extracted from The Cancer Genome Atlas (TCGA) database. Hypoxia-related lactate metabolism genes (HRLGs) were screened using Spearman's correlation analysis. A prognostic signature based on HRLGs was developed using the least absolute shrinkage and selection operator (LASSO) algorithm. A comprehensive analysis was conducted on the molecular features, immune environment, mutation patterns, and response to drugs between different risk groups. In vitro and in vivo experiments were performed to verify the function of KIF23. KEY FINDINGS: A five HRLG-based prognostic signature was identified. The prognostic outcome was unfavorable for the high-risk subgroup. Observation of increased pathway activities associated with cell proliferation and DNA damage repair was noted in the high-risk subgroup. Additionally, notable correlations were observed between risk score and immune microenvironment, mutational features, and drug responsiveness. Further, we confirmed KIF23 as a novel oncogene in UCEC, whose silencing decreased proliferation and promoted apoptosis of cancer cells. KIF23 knockdown reduced tumor growth in nude mice. We demonstrated that KIF23 was upregulated under hypoxic stress in a HIF-1α dependent manner. Moreover, KIF23 regulated lactate dehydrogenase A expression. SIGNIFICANCE: The developed HRLG-related signature was associated with prognosis, immune microenvironment, and drug sensitivity in UCEC. We also revealed KIF23 as a hypoxia-regulated lactate metabolism-related oncogene.


Asunto(s)
Neoplasias Endometriales , Oncogenes , Animales , Ratones , Humanos , Femenino , Ratones Desnudos , Oncogenes/genética , Mutación , Hipoxia , Neoplasias Endometriales/genética , Microambiente Tumoral/genética , Proteínas Asociadas a Microtúbulos
11.
Mar Environ Res ; 195: 106354, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38224625

RESUMEN

Cold-water coral (CWC) communities are biodiversity hotspots on the world's deep seafloor. Although deep-sea corals in the South China Sea (SCS) have been reported before, they are only sporadic. A comprehensive and systematic understanding of the CWC in the SCS would forge the basis for future protection. Here we conducted the first systematic survey on the CWCs in the following six broad-scale sub-regions, from the northwest and northeast slopes to the seamounts in the western and central basins of the SCS, through twenty-four dives of the human-occupied vehicle ShenhaiYongshi. Statistical analysis provided detailed information on the distribution, abundance, size, diversity, and density of CWCs and the in situ environmental conditions supporting coral habitats. We found that the SCS hosted highly diversified coral communities, including twelve genera of gorgonians, six genera of black corals, and one genus of stony corals. The differences in the spatial distribution patterns of coral communities suggested that several environmental variables (depth, temperature, salinity, substrate, and geomorphology) might influence the development of CWCs in the SCS. The intermediate water layer of the SCS appeared to provide suitable habitat for deep-sea coral communities and potentially promoted connectivity. Furthermore, differences between sub-regions within the SCS may be an important factor responsible for the biogeographic patterns of CWCs. These sub-regions of CWCs were observed to range from 0.004 to 0.622 corals m-2, with an average of 0.139 corals m-2. The mean density of CWCs in the SCS was relatively high compared to well-studied CWC hotspots. Overall, the results revealed the significance of the SCS as an important CWC hotspot in the world. These findings provide a fundamental basis for the protection of deep-sea coral assemblages in the SCS.


Asunto(s)
Antozoos , Animales , Humanos , Ecosistema , Agua , Temperatura , China , Arrecifes de Coral
12.
Zool Res ; 45(1): 215-225, 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38247179

RESUMEN

A total of 10 specimens of Alcyonacea corals were collected at depths ranging from 905 m to 1 633 m by the manned submersible Shenhai Yongshi during two cruises in the South China Sea (SCS). Based on mitochondrial genomic characteristics, morphological examination, and sclerite scanning electron microscopy, the samples were categorized into four suborders (Calcaxonia, Holaxonia, Scleraxonia, and Stolonifera), and identified as 9 possible new cold-water coral species. Assessments of GC-skew dissimilarity, phylogenetic distance, and average nucleotide identity (ANI) revealed a slow evolutionary rate for the octocoral mitochondrial sequences. The nonsynonymous ( Ka) to synonymous ( Ks) substitution ratio ( Ka/ Ks) suggested that the 14 protein-coding genes (PCGs) were under purifying selection, likely due to specific deep-sea environmental pressures. Correlation analysis of the median Ka/ Ks values of five gene families and environmental factors indicated that the genes encoding cytochrome b (cyt b) and DNA mismatch repair protein ( mutS) may be influenced by environmental factors in the context of deep-sea species formation. This study highlights the slow evolutionary pace and adaptive mechanisms of deep-sea corals.


Asunto(s)
Antozoos , Genoma Mitocondrial , Animales , Antozoos/genética , Filogenia , China , Citocromos b/genética
13.
Microorganisms ; 11(2)2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36838501

RESUMEN

The transition areas of riverine, estuarine, and marine environments are particularly valuable for the research of microbial ecology, biogeochemical processes, and other physical-chemical studies. Although a large number of microbial-related studies have been conducted within such systems, the vast majority of sampling have been conducted over a large span of time and distance, which may lead to separate batches of samples receiving interference from different factors, thus increasing or decreasing the variability between samples to some extent. In this study, a new in situ filtration system was used to collect membrane samples from six different sampling sites along the Sanya River, from upstream freshwater to the sea, over a nine-hour period. We used high-throughput sequencing of 16S and 18S rRNA genes to analyze the diversity and composition of prokaryotic and eukaryotic communities. The results showed that the structures of these communities varied according to the different sampling sites. The α-diversity of the prokaryotic and eukaryotic communities both decreased gradually along the downstream course. The structural composition of prokaryotic and eukaryotic communities changed continuously with the direction of river flow; for example, the relative abundances of Rhodobacteraceae and Flavobacteriaceae increased with distance downstream, while Sporichthyaceae and Comamonadaceae decreased. Some prokaryotic taxa, such as Phycisphaeraceae and Chromobacteriaceae, were present nearly exclusively in pure freshwater environments, while some additional prokaryotic taxa, including the SAR86 clade, Clade I, AEGEAN-169 marine group, and Actinomarinaceae, were barely present in pure freshwater environments. The eukaryotic communities were mainly composed of the Chlorellales X, Chlamydomonadales X, Sphaeropleales X, Trebouxiophyceae XX, Annelida XX, and Heteroconchia. The prokaryotic and eukaryotic communities were split into abundant, common, and rare communities for NCM analysis, respectively, and the results showed that assembly of the rare community assembly was more impacted by stochastic processes and less restricted by species dispersal than that of abundant and common microbial communities for both prokaryotes and eukaryotes. Overall, this study provides a valuable reference and new perspectives on microbial ecology during the transition from freshwater rivers to estuaries and the sea.

14.
Aging (Albany NY) ; 15(16): 8275-8297, 2023 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-37616056

RESUMEN

BACKGROUND: Intrauterine adhesion (IUA) is a troublesome complication characterized with endometrial fibrosis after endometrial trauma. Increasing number of investigations focused on autophagy and non-coding RNA in the pathogenesis of uterine adhesion, but the underlying mechanism needs to be further studied. METHODS: mRNA expression profile and miRNA expression profile were obtained from Gene Expression Omnibus database. The autophagy related genes were low. Venn diagram was used to set the intersection of autophagy genes and DEGs to obtain ARDEGs. Circbank was used to select hub autophagy-related circRNAs based on ARDEMs. Then, the differentially expressed autophagy-related genes, miRNAs and circRNAs were analyzed by functional enrichment analysis, and protein-protein interaction network analysis. Finally, the expression levels of hub circRNAs and hub miRNAs were validated through RT-PCR of clinical intrauterine adhesion samples. In vitro experiments were investigated to explore the effect of hub ARCs on cell autophagy, myofibroblast transformation and collagen deposition. RESULTS: 11 autophagy-related differentially expressed genes (ARDEGs) and 41 differentially expressed miRNA (ARDEMs) compared between normal tissues and IUA were identified. Subsequently, the autophagy-related miRNA-mRNA network was constructed and hub ARDEMs were selected. Furthermore, the autophagy-related circRNA-miRNA-mRNA network was established. According to the ranking of number of regulated ARDEMs, hsa-circ-0047959, hsa-circ-0032438, hsa-circ-0047301 were regarded as the hub ARCs. In comparison of normal endometrial tissue, all three hub ARCs were upregulated in IUA tissue. All hub ARDEMs were downregulated except has-miR-320c. CONCLUSIONS: In the current study, we firstly constructed autophagy-related circRNA-miRNA-mRNA regulatory network and identified hub ARCs and ARDEMs had not been reported in IUA.


Asunto(s)
MicroARNs , Enfermedades Uterinas , Femenino , Humanos , ARN Circular , Autofagia , ARN Mensajero
15.
Sci Total Environ ; 903: 166609, 2023 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-37657544

RESUMEN

Serpentinization of peridotite provides a significant source of energy for the subseafloor biosphere and abiotic organic synthesis. The presence of diverse micrometer-scale organic matter in serpentinites offers insights into deep carbon cycling and the origin of life on Earth. It is critical to maintain stringent lab protocols in analyzing serpentinite samples, limiting the contact with organic materials that could contaminate serpentinites and cause misinterpretations. However, the extent to which these organic materials (e.g. latex gloves or nylon polishing disc) can introduce contamination remains unclear. Here we subject serpentinite samples from the Yap Trench in the western Pacific Ocean to multi-stage cutting and polishing procedures prior to analysis. Our findings from electron microscopy reveal that micrometer-scale organic matter in serpentinites is randomly distributed either on the sample surface or within Cr-spinel fractures. Further analysis using Raman spectroscopy indicates that the organic matter contains several hydrogen bonding moieties, similar to those found in the latex gloves or nylon polishing disc used during the treatment of serpentinite samples. Our results suggest that the detected organic matter is likely due to contamination from the organic materials involved during sample processing. Thus, future studies need to carefully assess micrometer-scale organic contamination and limit the use of organic materials when analyzing organic compounds hosted in serpentinites, not only on Earth but also on other rocky planets.

16.
Microbiol Spectr ; 11(6): e0206923, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37943079

RESUMEN

IMPORTANCE: A distinct distribution pattern was shaped by a deterministic process. Enhanced vertical connectivity expanded the previous understanding of seamount effects. Parasitism and predation were prevalent in the seamounts.


Asunto(s)
Eucariontes , Sedimentos Geológicos , Agua de Mar , Océano Pacífico , Sedimentos Geológicos/microbiología , Agua de Mar/microbiología
17.
Proc Natl Acad Sci U S A ; 106(12): 4840-5, 2009 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-19273854

RESUMEN

Deep-sea hydrothermal vents are one of the most unique and fascinating ecosystems on Earth. Although phylogenetic diversity of vent communities has been extensively examined, their physiological diversity is poorly understood. In this study, a GeoChip-based, high-throughput metagenomics technology revealed dramatic differences in microbial metabolic functions in a newly grown protochimney (inner section, Proto-I; outer section, Proto-O) and the outer section of a mature chimney (4143-1) at the Juan de Fuca Ridge. Very limited numbers of functional genes were detected in Proto-I (113 genes), whereas much higher numbers of genes were detected in Proto-O (504 genes) and 4143-1 (5,414 genes). Microbial functional genes/populations in Proto-O and Proto-I were substantially different (around 1% common genes), suggesting a rapid change in the microbial community composition during the growth of the chimney. Previously retrieved cbbL and cbbM genes involved in the Calvin Benson Bassham (CBB) cycle from deep-sea hydrothermal vents were predominant in Proto-O and 4143-1, whereas photosynthetic green-like cbbL genes were the major components in Proto-I. In addition, genes involved in methanogenesis, aerobic and anaerobic methane oxidation (e.g., ANME1 and ANME2), nitrification, denitrification, sulfate reduction, degradation of complex carbon substrates, and metal resistance were also detected. Clone libraries supported the GeoChip results but were less effective than the microarray in delineating microbial populations of low biomass. Overall, these results suggest that the hydrothermal microbial communities are metabolically and physiologically highly diverse, and the communities appear to be undergoing rapid dynamic succession and adaptation in response to the steep temperature and chemical gradients across the chimney.


Asunto(s)
Bacterias/genética , Manantiales de Aguas Termales/microbiología , Metaboloma/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Secuencia de Bases , Canadá , Dióxido de Carbono/metabolismo , Células Clonales , Biblioteca de Genes , Genes Bacterianos , Variación Genética , Metales , Metano/metabolismo , Nitrógeno/metabolismo , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Ribulosa-Bifosfato Carboxilasa/genética
18.
Front Bioeng Biotechnol ; 10: 856745, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35392402

RESUMEN

Uterine fibroids (UF) are the most common benign gynecologic tumors and lead to heavy menstrual bleeding, severe anemia, abdominal pain, and infertility, which seriously harm a women's health. Unfortunately, the regulatory mechanisms of UF have not been elucidated. Recent studies have demonstrated that miRNAs play a vital role in the development of uterine fibroids. As a high-throughput technology, microarray is utilized to identify differentially expressed genes (DEGs) and miRNAs (DEMs) between UF and myometrium. We identified 373 candidate DEGs and the top 100 DEMs. Function enrichment analysis showed that candidate DEGs were mainly enriched in biological adhesion, locomotion and cell migration, and collagen-containing extracellular matrix. Subsequently, protein-protein interaction (PPI) networks are constructed to analyze the functional interaction between DEGs and screen hub DEGs. Subsequently, the expression levels of hub DEGs were validated by real-time PCR of clinical UF samples. The DGIdb database was used to select candidate drugs for hub DEGs. Molecular docking was applied to test the affinity between proteins and drugs. Furthermore, target genes for 100 candidate DEMs were predicted by miRwalk3.0. After overlapping with 373 candidate DEGs, 28 differentially expressed target genes (DEGTs) were obtained. A miRNA-mRNA network was constructed to investigate the interactions between miRNA and mRNA. Additionally, two miRNAs (hsa-miR-381-3p and hsa-miR-181b-5p) were identified as hub DEMs and validated through RT-PCR. In order to better elucidate the pathogenesis of UF and the synergistic effect between miRNA and transcription factor (TF), we constructed a miRNA-TF-mRNA regulatory network. Meanwhile, in vitro results suggested that dysregulated hub DEMs were associated with the proliferation, migration, and apoptosis of UF cells. Our findings provided a novel horizon to reveal the internal mechanism and novel targets for the diagnosis and treatment of UF.

19.
Carbohydr Polym ; 298: 120081, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36241273

RESUMEN

Self-healing natural hydrogels still suffer from some issues such as unfit stiffness, poor healing efficiency, and lack of biocompatibility and hydrolytic stability, although they have been used to treat spinal cord injury (SCI). Herein, we develop the injectable, self-healing hyaluronate hydrogels based on multiple dynamic covalent bonds. The hydrogels exhibit fast gelation and excellent self-healing capability as well as injectability, favoring in situ formation for the hydrogels in target sites and maintaining their structural stability. Furthermore, the hydrogels are compatible with neural stem cells and various tissues and possess proper stiffness similar to nervous tissue. Interestingly, the hydrogel can induce neural differentiation of neural stem cells. In vivo experiment further illustrates that the hydrogels promote angiogenesis and remyelination as well as neuron regeneration, leading to the significant locomotor recovery of the SCI model rats. This injectable self-healing hyaluronic acid-based hydrogel is a potential candidate for nerve repair.


Asunto(s)
Hidrogeles , Traumatismos de la Médula Espinal , Animales , Glicosaminoglicanos , Ácido Hialurónico/farmacología , Hidrogeles/química , Hidrogeles/farmacología , Ratas , Traumatismos de la Médula Espinal/tratamiento farmacológico
20.
Materials (Basel) ; 15(16)2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-36013871

RESUMEN

Prefabricated composite shear walls (PCSW) consisting of steel plate clapped by single-sided or double-sided prefabricated reinforced concrete (RC) panels have enormous advantages for application as lateral-resisting structures in prefabricated high-rising residential buildings. In this paper, three 1/3-scaled PCSW were manufactured and tested to investigate the seismic performance of PCSW with single-sided or double-sided prefabricated RC panels. The experimental results, including hysteretic and skeleton curves, stiffness and strength degradation, ductility, energy dissipation capability and steel frame effects, were interpreted, compared and summarized. In spite of the RC panels being the same thickness, PCSW with double-sided RC panels had the most outstanding lateral-resisting properties: the highest yield strength and bearing capacity, adequate ductility, plumper and stable hysteresis loop and excellent energy absorption capacity. Finally, a simple predicting equation with a modification coefficient to calculate the effects of boundary steel frame was summarized and proposed to calculate the lateral yield load of the PCSW. All efforts were made to give reliable technical references for the design and construction of the PCSW.

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