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1.
J Environ Manage ; 331: 117171, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36623360

RESUMEN

Macroalgae and seagrass wash ashore by tidal waters and episodic events and create an ocean-to-land transport of carbon and nutrients. On land, these deposits (beach wrack) are consumed by macrofauna, remineralized by microorganisms, or washed back to the sea, during which recycling of carbon and nitrogen affect the biochemical cycles in coastal zones. Manual quantification of beach wracks is time-consuming and often difficult due to complex topography and remote locations. Here, we present a novel method using Unoccupied Aerial Vehicle (UAV) photogrammetry combined with in situ measurements of carbon and nitrogen contents of wrack to quantify marine carbon and nutrient deposits in beach zones. The UAV method was tested against placed cubes ranging from 125 to 88,218 cm3 and demonstrated a high accuracy (R2 > 0.99) for volume acquisition when compared to manual measurements. Also, the UAV-based assessments of the cross-sectional area of beach deposits demonstrated a high accuracy when compared to manual and high-precision GNSS (Global Navigation Satellite System) measurements without significant differences between the methods. This demonstrated that UAVs can provide detailed spatial maps, three-dimensional (3D) surface models, and accurate volumetric assessments of beach wrack deposits. In three case studies, combined with carbon and nitrogen measures, total organic carbon and nitrogen deposits in beach wracks were quantified ranging from 4.3 to 9.7 and from 0.3 to 0.5 kg per meter coastline, respectively. In conclusion, this UAV method demonstrated an effective tool to quantify ecosystem carbon and nitrogen deposits relevant to ecosystem assessments and quantification of blue carbon stocks. The method is optimal when the terrain below beach wrack deposits is known, as in the case with before-and-after or repeated surveys. Further, UAVs display strong time- and cost-effective advantages over manual methods which is amplified with increasing project scale. We propose it as a valuable method for multiple scientific and commercial applications related to environmental monitoring and management, including marine resource exploration and exploitation.


Asunto(s)
Ecosistema , Algas Marinas , Monitoreo del Ambiente/métodos , Carbono , Nitrógeno
2.
Small ; 16(48): e2005639, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33169499

RESUMEN

The disordered dendritic growth of Li metal seriously hampers the practical application of lithium metal batteries. Great efforts are devoted to suppress the growth of dendrites, it is still necessary to explore measures of controlling dendritic growth and pave ways for normal cell operation in presence of dendrites. Herein, a modification technique of Li metal anode by a periodic Ni mesh with micrometer-sized grid is proposed for interfacial engineering. Periodic patterned Ni mesh is prepared using a novel laser direct-writing technique combined with selective electrodeposition process. The growth of Li dendrites is regulated under the effect of unique electric field distribution by the introduction of the Ni mesh. It is noteworthy that the controlled lateral growth of dendrites is successfully realized by the internal structure modification instead of any external electric or magnetic field as has been previously reported. The resultant anode exhibits a stable cycling performance with ultralow overpotential of 6-8 mV for over 1000 h at the current density of 0.5 mA cm-2 . It also presents superior electrochemical performance when assembled against LiFePO4 cathode into full cells, with an initial capacity of 133 mA h g-1 and a stable cycling performance over 160 cycles.

3.
Ecol Appl ; 29(7): e01967, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31257690

RESUMEN

Revegetation of pioneer plants is a critical phase in community establishment for mudflats in seriously degraded coastal wetlands. We tested a hypothesis of the importance of a "power balance" among propagule resilience and sedimentary and tidal disturbances for vegetation reestablishment. Our experiment used three types of propagules (seeds, seedlings, and corms) of native Scirpus species in the fringing flats with similar tidal flows and varying sedimentary intensities in the Yangtze Estuary. Regardless of the initial planting densities, the seed germination rate was extremely low in the field situation. Although the incubated seedlings were planted directly on the bare flat, the wave movement easily flushed the seedlings, even at the site with moderate sedimentary accretion. Failure of the revegetation practice using the seed and seedling materials indicated that the combined "growing and anchoring power" of young seedlings and "stabilizing power" of the sediment were insufficient to withstand the "dislodging power" of the tidal energy. In contrast, the planting approach with underground propagules (corms) proved to be feasible for vegetation establishment at the sites with moderate and low-level sedimentary intensities. The successful practice improved the tipping point of plant survival and tussock formation could be surpassed when the combined growing and anchoring power of seedlings that developed from corms with the stabilizing power of the sediment was greater than the dislodging power of the wave energy. However, at the site with high-level sedimentary intensity, the excessive sediment converted to the burying stress power as seedlings developed from the corms, revealing a burial threshold for seedling survival. The risk of seedling establishment was high when the burying stress power of the sediment far outweighed the combination of the growing power of the seedlings and the sediment removal power of the tidal current and surpassed the tipping point of vegetation die-off. Additionally, we checked the practice cost of the different approaches to ensure a highly cost-effective revegetation planning based on site suitability. This study highlights that understanding of the propagule-sediment-tide power balance offers a tool for improvement of the revegetation and management of site-specific sedimentary and hydrological environments for many degraded coastal ecosystems.


Asunto(s)
Ecosistema , Estuarios , Plantones , Semillas , Humedales
4.
Ecol Evol ; 14(6): e11582, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38932977

RESUMEN

Climate change significantly impacted on the survival, development, distribution, and abundance of living organisms. The Chinese serow Capricornis milneedwardsii, known as the "four unlike," is a Class II nationally protected species in China. In this study, we predicted the geographical suitability of C. milneedwardsii under current and future climatic conditions using MaxEnt. The model simulations resulted in area under the receiver operating characteristic curve (AUC) values above 0.9 for both current and future climate scenarios, indicating the excellent performance, high accuracy, and credibility of the MaxEnt model. The results also showed that annual precipitation (Bio12), slope, elevation, and mean temperature of wettest quarter (Bio8) were the key environmental variables affecting the distribution of C. milneedwardsii, with contributions of 31.2%, 26.4%, 11%, and 10.3%, respectively. The moderately and highly suitable habitats were mainly located in the moist area of China, with a total area of 34.56 × 104 and 16.61 × 104 km2, respectively. Under future climate change scenarios, the areas of suitability of C. milneedwardsii showed an increasing trend. The geometric center of the total suitable habitats of C. milneedwardsii would show the trend of northwest expansion and southeast contraction. These findings could provide a theoretical reference for the protection of C. milneedwardsii in the future.

5.
Sci Total Environ ; 935: 173232, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-38761926

RESUMEN

Biogeochemical processes mediated by plants and soil in coastal marshes are vulnerable to environmental changes and biological invasion. In particular, tidal inundation and salinity stress will intensify under future rising sea level scenarios. In this study, the interactive effects of flooding regimes (non-waterlogging vs. waterlogging) and salinity (0, 5, 15, and 30 parts per thousand (ppt)) on photosynthetic carbon allocation in plant, rhizodeposition, and microbial communities in native (Phragmites australis) and invasive (Spartina alterniflora) marshes were investigated using mesocosm experiments and 13CO2 pulse-labeling techniques. The results showed that waterlogging and elevated salinity treatments decreased specific root allocation (SRA) of 13C, rhizodeposition allocation (RA) 13C, soil 13C content, grouped microbial PLFAs, and the fungal 13C proportion relative to total PLFAs-13C. The lowest SRA, RA, and fungal 13C proportion occurred under the combined waterlogging and high (30 ppt) salinity treatments. Relative to S. alterniflora, P. australis displayed greater sensitivity to hydrological changes, with a greater reduction in rhizodeposition, soil 13C content, and fungal PLFAs. S. alterniflora showed an earlier peak SRA but a lower root/shoot 13C ratio than P. australis. This suggests that S. alterniflora may transfer more photosynthetic carbon to the shoot and rhizosphere to facilitate invasion under stress. Waterlogging and high salinity treatments shifted C allocation towards bacteria over fungi for both plant species, with a higher allocation shift in S. alterniflora soil, revealing the species-specific microbial response to hydrological stresses. Potential shifts towards less efficient bacterial pathways might result in accelerated carbon loss. Over the study period, salinity was the primary driver for both species, explaining 33.2-50.8 % of 13C allocation in the plant-soil-microbe system. We propose that future carbon dynamics in coastal salt marshes under sea-level rise conditions depend on species-specific adaptive strategies and carbon allocation patterns of native and invasive plant-soil systems.


Asunto(s)
Especies Introducidas , Fotosíntesis , Salinidad , Humedales , Poaceae , Carbono/metabolismo , Hidrología , Suelo/química , Raíces de Plantas/metabolismo
6.
Foods ; 12(13)2023 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-37444176

RESUMEN

The traceability of quality mineral fingerprints in the viscera of Tan sheep from northwest China was studied. Twenty-five mineral elements in the heart and liver samples of Tan sheep were determined using an inductively coupled plasma mass spectrometer (ICP-MS), and the characteristics of the mineral elements in the visceral tissues of the Tan sheep were further analyzed in combination with a principal component analysis (PCA), hierarchical cluster analysis (HCA), and linear discriminant analysis (LDA) to establish a discriminant model and verify it. The results show that 11 elements (137Ba, 43Ca, 63Cu, 56Fe, 39K, 31P, 60Ni, 78Se, 118Sn, 125Te, and 66Zn) in the Tan sheep heart samples had significant differences among different regions (p < 0.05), and the results of the LDA show that the accuracy rate of the return-generation examination was 85.70%, and the accuracy rate of the hand-over-fork examination was 87.50%; 10 elements (111Cd, 59Co, 52Cr, 56Fe, 39K, 55Mn, 95Mo, 23Na, 121Sb, and 78Se) in the Tan sheep liver samples had significant differences among different regions (p < 0.05), and the results of the LDA showed that the accuracy rate of the return-generation examination was 96.30%, and the accuracy rate of the hand-over-fork examination was 86.25%. This indicates that the multi-element analysis has potential for determining the origin of Tan sheep viscera in certain regions.

7.
J Med Chem ; 66(10): 7016-7037, 2023 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-37184921

RESUMEN

A novel series of benzamide derivatives were successively designed and synthesized prepared from the pyridazinone scaffold. Among them, (S)-17b, demonstrated potent inhibitory activity in vitro toward human class I HDAC isoforms and human myelodysplastic syndrome (SKM-1) cell line. Also, (S)-17b strongly increased the intracellular level of acetyl-histone H3 and P21 simultaneously and effectively induced G1 cell cycle arrest and apoptosis. Through oral dosing in SKM-1 xenograft models, (S)-17b exhibited excellent in vivo antitumor activity. In addition, compound (S)-17b showed better antitumor efficacy on mouse models with intact immune system than those with thymus deficiencies. Furthermore, this compound displayed a favorable pharmacokinetic profile in ICR mice and SD rat, respectively, minimal metabolic property differences among hepatocytes from five species, and a low inhibition upon the human ether-a-go-go (hERG) channel with an IC50 value of 34.6 µΜ. This novel compound (S)-17b may serve as a new drug candidate for further investigation.


Asunto(s)
Antineoplásicos , Inhibidores de Histona Desacetilasas , Ratones , Humanos , Ratas , Animales , Inhibidores de Histona Desacetilasas/uso terapéutico , Inhibidores de Histona Desacetilasas/farmacocinética , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacocinética , Ratas Sprague-Dawley , Ratones Endogámicos ICR , Modelos Animales de Enfermedad , Benzamidas/farmacología , Proliferación Celular , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Apoptosis , Relación Estructura-Actividad
8.
Comput Math Methods Med ; 2022: 4117261, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36277003

RESUMEN

A hand-held Raman spectroscopic device was used as a rapid nondestructive testing device to predict the metmyoglobin (MetMb) and metmyoglobin reductase activity (MRA) values on the surface layer of fresh beef. Longissimus dorsi muscles were from 10 young bulls (Holstein-Friesian) from two different cattle farms (group A = 5 and B = 5). The Raman spectra of 100 samples were correlated with the MetMb and MRA values using partial least squares regression (PLSR). Two groups could be discriminated, and the separate correlation models were better than the joint correlation model for the fresh beef. The coefficients of determination are R 2 = 0.81 (group A) and R 2 = 0.87 (group B) for MetMb and R 2 = 0.80 (group A) and R 2 = 0.85 (group B) for MRA. The results show the usefulness of Raman spectra in predicting the inner traits such as MetMb and MRA during meat storage. In conclusion, it is feasible to determine the MetMb and MRA values by Raman spectroscopy. Color is an important indicator of beef freshness and can vary depending on the age, sex, and breed of the cow. They play a very important role in human nutrition. The color of meat is an important indicator of meat freshness, and many researchers are already investigating the causes of color changes. The research was conducted in this environment.


Asunto(s)
Metamioglobina , NADH NADPH Oxidorreductasas , Bovinos , Masculino , Animales , Humanos , Metamioglobina/química , Carne/análisis
9.
Eur J Med Chem ; 236: 114259, 2022 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-35395439

RESUMEN

Novel pyrrolopyridone BET degraders were designed and synthesized based on the binding mode between the pyrrolopyridone BET inhibitor with the BRD4 protein. The potent degraders on MV-4-11 cells were discovered through structure-activity relationship study. Modification of warhead on pyrrolopyridone BET degraders significantly regulates BRD4 isoform (long and short) protein degradation, which induces differential cell cycle arrest and apoptosis on MV-4-11 cells. Docking study revealed that the fine structural modification of BET degraders may bind with the BD domain of BRD4 protein to engage various surface areas that bind with CRBN.


Asunto(s)
Antineoplásicos , Proteínas Nucleares , Antineoplásicos/farmacología , Proteínas de Ciclo Celular , Proteínas Nucleares/metabolismo , Relación Estructura-Actividad , Factores de Transcripción/metabolismo
10.
Adv Healthc Mater ; 10(18): e2100046, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34263551

RESUMEN

Monitoring the concentration of useful biomarkers via electronic skins (e-skins) is highly important for the development of wearable health management systems. While some biosensor e-skins with high flexibility, sensitivity, and stability have been developed, little attention has been paid to their long-term comfortability and optical transparency. Here, a conformable, gas permeable, and transparent skin-like Cu2 O@Ni micromesh structural glucose monitoring patch is reported. With its self-supporting micromesh structure, the skin-like glucose monitoring patch exhibits excellent shape conformability, high gas permeability, and high optical transmittance. The skin-like glucose biosensor achieves real-time monitoring of glucose concentrations with high sensitivity (15 420 µA cm-2 mM-1 ), low detection limit (50 nM), fast response time (<2 s), high selectivity, and long-term stability. These desirable performance properties arise from the synergistic effects of the self-supporting micromesh configuration, high conductivity of the metallic Ni micromesh, and high electrocatalytic activities of the Cu2 O toward glucose. This work presents a versatile and efficient strategy for constructing conformable, gas permeable, and transparent biosensor e-skins with excellent practicability towards wearable electronics.


Asunto(s)
Técnicas Biosensibles , Dispositivos Electrónicos Vestibles , Glucemia , Automonitorización de la Glucosa Sanguínea , Piel
11.
Sci Total Environ ; 773: 145684, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33940760

RESUMEN

Intertidal creeks play an important role in transporting nutrients between coastal ecosystems and ocean. Reclamation is a predominant anthropogenic disturbance in coastal regions; however, the influence of reclamation on carbon and nitrogen species and greenhouse gas (GHG) fluxes in creek remains unclear. In a subtropical salt marsh of eastern China, the seasonal patterns of dissolved carbon (DOC, DIC, CO2, and CH4) and inorganic nitrogen (NH4+-N, NO2--N, and NO3--N and N2O) species, and the diffusive fluxes of CO2, CH4, and N2O, were compared between the natural tidal creeks and the reclaimed creeks. Due to notably changed hydrological and biological conditions in the reclaimed creeks, concentrations of all dissolved carbon species, NH4+-N and NO2--N increased significantly by 60.2-288.2%, while NO3--N and N2O decreased slightly, compared to the natural tidal creeks. DIC and NO3--N were the primary components of the total dissolved carbon and inorganic nitrogen in both creek types; however, their proportions decreased as a result of elevated DOC, CO2, CH4, NH4+-N, and NO2--N following reclamation. Significantly higher global warming potential (0.58 ± 0.15 g CO2-eq m-2 d-1) was found in the reclaimed creeks, making them hotspot of greenhouse effects, compared to the natural tidal creeks. Our results indicated that changes in flow velocity, salinity, Chlorophyll a, and pH were the main factors controlling the dissolved carbon and nitrogen and consequent GHG emissions, due to reclamation. This study is helpful in understanding of carbon and nitrogen sink-source shifts resulting from land use changes in coastal wetlands.

12.
Acta Pharm Sin B ; 11(2): 488-504, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33643826

RESUMEN

Medulloblastoma (MB) is a common yet highly heterogeneous childhood malignant brain tumor, however, clinically effective molecular targeted therapy is lacking. Modulation of hedgehog (HH) signaling by epigenetically targeting the transcriptional factors GLI through bromodomain-containing protein 4 (BRD4) has recently spurred new interest as potential treatment of HH-driven MB. Through screening of current clinical BRD4 inhibitors for their inhibitory potency against glioma-associated oncogene homolog (GLI) protein, the BRD4 inhibitor 2 was selected as the lead for further structural optimization, which led to the identification of compounds 25 and 35 as the high potency HH inhibitors. Mechanism profiling showed that both compounds suppressed HH signaling by interacting with the transcriptional factor GLI, and were equally potent against the clinical resistant mutants and the wild type of smoothened (SMO) receptor with IC50 values around 1 nmol/L. In the resistant MB allograft mice, compound 25 was well tolerated and markedly suppressed tumor growth at both 5 mg/kg (TGI = 83.3%) and 10 mg/kg (TGI = 87.6%) doses. Although further modification is needed to improve the pharmacokinetic (PK) parameters, compound 25 represents an efficacious lead compound of GLI inhibitors, possessing optimal safety and tolerance to fight against HH-driven MB.

13.
Eur J Med Chem ; 209: 112868, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33077265

RESUMEN

According to the binding mode of ABBV-744 with bromodomains and the cape space of HDAC, the novel selective HDAC/BRD4 dual inhibitors were designed and synthesized by the pharmacophore fusion strategy. Evaluating the biomolecular activities through SARs exploration identified three kinds of selective dual inhibitors 41c (HDAC1/BRD4), 43a (pan-HDAC/BRD4) and 43d (HDAC6/BRD4(BD2)), whose target-related cellular activities in MV-4-11 cells were also confirmed. Significantly, the selective dual inhibitor 41c (HDAC1/BRD4) exhibited synergistic effects against MV-4-11 cells, which strongly induced G0/G1 cell cycle arrest and apoptosis, and the first HDAC6/BRD4(BD2) dual inhibitor was found. This study provides support for selective HDAC/BRD4 dual inhibitors as epigenetic probes based on pyrrolopyridone core for the future biological evaluation in different cancer cell lines.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Proteínas de Ciclo Celular/antagonistas & inhibidores , Inhibidores de Histona Desacetilasas/química , Inhibidores de Histona Desacetilasas/farmacología , Factores de Transcripción/antagonistas & inhibidores , Apoptosis/efectos de los fármacos , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Diseño de Fármacos , Descubrimiento de Drogas , Ensayos de Selección de Medicamentos Antitumorales , Epigénesis Genética/efectos de los fármacos , Humanos , Ácidos Hidroxámicos/química , Ácidos Hidroxámicos/farmacología , Modelos Moleculares , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Piridinas/química , Piridinas/farmacología , Piridonas/química , Piridonas/farmacología , Pirroles/química , Pirroles/farmacología , Factores de Transcripción/metabolismo
14.
Meat Sci ; 169: 108194, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32521405

RESUMEN

The feasibility of combining spectral and textural information from hyperspectral imaging to improve the prediction of the C16:0 and C18:1 n9 contents for lamb was explored. 29 and 22 optimal wavelengths were selected for the C16:0 and C18:1 n9 contents, respectively, by conducting the variable combination population analysis-iteratively retaining informative variables (VCPA-IRIV) algorithm. To extract the textural features of images, a gray-level co-occurrence matrix (GLCM) analysis was implemented in the first principal component image. The least squares support vector machine (LSSVM) model and the partial least squares regression (PLSR) model were developed to predict the C16:0 and C18:1 n9 contents from the spectra and the fusion data. The distribution map was visualized using the best model with the imaging process. The results showed that the combination of the spectral and textural information of hyperspectral imaging coupled with the VCPA-IRIV algorithm had strong potential for the prediction and visualization of the C16:0 and C18:1 n9 contents of lamb.


Asunto(s)
Ácido Oléico/análisis , Ácido Palmítico/análisis , Carne Roja/análisis , Algoritmos , Animales , Imágenes Hiperespectrales/métodos , Imágenes Hiperespectrales/veterinaria , Análisis de los Mínimos Cuadrados , Análisis de Componente Principal , Oveja Doméstica , Máquina de Vectores de Soporte
15.
J Mater Chem B ; 8(9): 1878-1896, 2020 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-32037409

RESUMEN

Cancer-specific bioimaging has been correlated with fluorescence-guided tumor therapy, garnering extensive interest from researchers. Herein, a highly efficient tumor-targeting fluorescent probe (NP-001), which is integrated with 4-hydroxy-1,8-naphthalimide and NVP-AUY922, for tumor imaging has been established. 4-Hydroxy-1,8-naphthalimide is a fluorescent molecule with remarkable imaging compatibility. NVP-AUY922 is a heat shock protein 90 (HSP90) inhibitor with preferential tumor selectivity that is conjugated to 4-hydroxy-1,8-naphthalimide as a tumor-targeting ligand. NP-002, a resorcinol-blocked probe which prevented binding with an amino acid residue of the HSP90 ATP binding pocket, was also synthesized as a control. In vitro and ex vivo assays showed that NP-001 could arrest cell proliferation, induce apoptosis and accumulate to inhibit HSP90. Confocal laser scanning microscopy (CLSM) also confirmed that NP-001 could be selectively internalized by tumor cells for cancer-specific bioimaging. Moreover, pharmacokinetic studies and histological analysis also indicated that NP-001 had a relatively longer retention time and showed no major organ-related toxicities. Overall, these encouraging data suggest that NP-001 is a promising new candidate for the early diagnosis of metastatic disease as well as targeted tumor imaging.


Asunto(s)
Colorantes Fluorescentes/química , Isoxazoles/química , Imagen Óptica , Resorcinoles/química , Apoptosis/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/farmacología , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Proteínas HSP90 de Choque Térmico/metabolismo , Humanos , Isoxazoles/farmacología , Estructura Molecular , Resorcinoles/farmacología , Determinantes Sociales de la Salud
16.
Sci Total Environ ; 747: 141214, 2020 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-32795794

RESUMEN

Coastal marshes have a significant capacity to sequester carbon; however, sea-level rise (SLR) is expected to result in prolonged flooding and saltwater intrusion in coastal regions. To explore the effects of SLR projections on net CO2 uptake in coastal marshes, we conducted a "double-check" investigation, including the eddy covariance (EC) measurements of the CO2 fluxes in subtropical coastal marshes along inundation and salinity gradients, in combination with a mesocosm experiment for analyzing CO2 flux components under waterlogging and increased salinity conditions. During the same measurement periods, the net ecosystem CO2 exchange (NEEEC based on the EC dataset) in an oligohaline marsh was higher than that in a low-elevation mesohaline marsh, whereas the NEEEC was lower than that in a high-elevation freshwater marsh. The declines in NEEEC between the marshes could be attributed to a greater decrease in gross primary production relative to ecosystem respiration. Waterlogging slightly increased the NEEms (NEE based on the mesocosms) because of inhibited soil respiration and slight changes in plant photosynthesis and shoot respiration. However, the NEEms measured during the drainage period decreased significantly due to the stimulated soil respiration. The NEEms decreased with increasing salinity (except under mild salinity), and waterlogging exacerbated the adverse impacts of salinity. The amplificatory effect of decreases in both leaf photosynthesis and growth under hydrological stresses contributed more to reduce the NEEms than to respiratory effluxes. Both waterlogging and increased salinity reduced the root biomass, soil microbial biomass, and activities of assayed soil enzymes (except for cellulase under waterlogging conditions), leading to limited soil respiration. The declines in plant growth, photosynthesis, and soil respiration could also be attributed to the decrease in soil nutrients under waterlogging and increased salinity conditions. We propose that the coupling of SLR-driven hydrological effects lowers the capacity of CO2 uptake in subtropical coastal marshes.


Asunto(s)
Dióxido de Carbono , Humedales , Dióxido de Carbono/análisis , Ecosistema , Elevación del Nivel del Mar , Suelo
17.
Stem Cell Res Ther ; 10(1): 220, 2019 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-31358062

RESUMEN

BACKGROUND: Human naïve pluripotency state cells can be derived from direct isolation of inner cell mass or primed-to-naïve resetting of human embryonic stem cells (hESCs) through different combinations of transcription factors, small molecular inhibitors, and growth factors. Long noncoding RNAs (lncRNAs) have been identified to be crucial in diverse biological processes, including pluripotency regulatory circuit of mouse pluripotent stem cells (PSCs), but few are involved in human PSCs' regulation of pluripotency and naïve pluripotency derivation. This study initially planned to discover more lncRNAs possibly playing significant roles in the regulation of human PSCs' pluripotency, but accidently identified a lncRNA whose knockdown in human PSCs induced naïve-like pluripotency conversion. METHODS: Candidate lncRNAs tightly correlated with human pluripotency were screened from 55 RNA-seq data containing human ESC, human induced pluripotent stem cell (iPSC), and somatic tissue samples. Then loss-of-function experiments in human PSCs were performed to investigate the function of these candidate lncRNAs. The naïve-like pluripotency conversion caused by CCDC144NL-AS1 knockdown (KD) was characterized by quantitative real-time PCR, immunofluorescence staining, western blotting, differentiation of hESCs in vitro and in vivo, RNA-seq, and chromatin immunoprecipitation. Finally, the signaling pathways in CCDC144NL-AS1-KD human PSCs were examined through western blotting and analysis of RNA-seq data. RESULTS: The results indicated that knockdown of CCDC144NL-AS1 induces naïve-like state conversion of human PSCs in the absence of additional transcription factors or small molecular inhibitors. CCDC144NL-AS1-KD human PSCs reveal naïve-like pluripotency features, such as elevated expression of naïve pluripotency-associated genes, increased developmental capacity, analogous transcriptional profiles to human naïve PSCs, and global reduction of repressive chromatin modification marks. Furthermore, CCDC144NL-AS1-KD human PSCs display inhibition of MAPK (ERK), accumulation of active ß-catenin, and upregulation of some LIF/STAT3 target genes, and all of these are concordant with previously reported traits of human naïve PSCs. CONCLUSIONS: Our study unveils an unexpected role of a lncRNA, CCDC144NL-AS1, in the naïve-like state conversion of human PSCs, providing a new perspective to further understand the regulation process of human early pluripotency states conversion. It is suggested that CCDC144NL-AS1 can be potentially valuable for future research on deriving higher quality naïve state human PSCs and promoting their therapeutic applications.


Asunto(s)
ARN Largo no Codificante/metabolismo , Línea Celular , Análisis por Conglomerados , Regulación hacia Abajo , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Células Madre Embrionarias Humanas/citología , Células Madre Embrionarias Humanas/metabolismo , Humanos , Cariotipo , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Interferencia de ARN , ARN Largo no Codificante/antagonistas & inhibidores , ARN Largo no Codificante/genética , ARN Interferente Pequeño/metabolismo , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transcriptoma
18.
Neuroreport ; 29(13): 1121-1128, 2018 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-29965871

RESUMEN

Long noncoding RNAs have been implicated in oligodendrocyte myelination and oligodendrocyte maturation, but their roles in normal oligodendrocyte differentiation are not fully defined. Here, we report a novel nonprotein-coding RNA, named lnc158, discovered in mouse oligodendrocytes identified in subependymal ventricular zone tissue by single-cell RNA sequencing. Lnc158 is an endogenous antisense transcript of nuclear factor-IB (NFIB) and complementary to 3' untranslated region of NFIB mRNA. NFIB is a member of the nuclear factor-I family and is essential in the development of many organs such as brains and lungs. We found that lnc158 transcripts serve a biological function by regulating the transcription level of the NFIB coding gene in neural stem cells. Overexpression of lnc158 increased the expression of NFIB mRNA and knockdown of lnc158 decreased the expression of NFIB mRNA, suggesting that NFIB is regulated positively by lnc158. Further analyses showed that overexpression of lnc158 in neural stem cells induced a modest increase in CNP, MBP, MAG, and OSP mRNA level, and enhanced induction of differentiation along the lineage of oligodendrocytes. These results together imply that lnc158 positively modulates the transcription level of NFIB mRNA, leading to the enhanced induction of oligodendrocytes.


Asunto(s)
Diferenciación Celular , Factores de Transcripción NFI/metabolismo , Células-Madre Neurales/metabolismo , Oligodendroglía/metabolismo , Regiones no Traducidas 3' , Animales , Células Cultivadas , Regulación del Desarrollo de la Expresión Génica , Ratones Endogámicos C57BL
19.
Ying Yong Sheng Tai Xue Bao ; 26(8): 2518-24, 2015 Aug.
Artículo en Zh | MEDLINE | ID: mdl-26685617

RESUMEN

During 2010 to 2012, fish diversity in Qingcaosha Reservoir was studied based on gillnets (multi-mesh monofilament gillnets and single-mesh trammel gillnets), electric fishing, bottom trawl and cage. The investigation collected a total of 34 fish species, belonging to 8 orders, 12 families. Cypriniformes contained the largest number of species (19 species) in the collection, followed by Perciformes (6 species). Multi-mesh monofilament gillnets sampled 19 fish species, of which Coilia nasus was the dominant species. Hierarchical cluster analysis indicated that mesh size of monofilament gillnets had significant influence on the composition of catches: C. nasus and Hemiculter bleekeri were the dominant species of catches of gillnet netting with mesh size of 2 cm, while C. nasus was the dominant species of catches of the nettings with mesh sizes larger than 2 cm. Species numbers and the catch per unit of effort ( CPUE) had a decreasing tendency with the increasing mesh size. Mesh size also had significant effects on the total length distribution of the dominant species C. nasus, which increased with the increasing mesh size. The results suggested that a combination of several gears was required to reliably estimate fish diversity of standing waters.


Asunto(s)
Biodiversidad , Cyprinidae , Animales , China , Análisis por Conglomerados
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