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1.
Mar Pollut Bull ; 198: 115771, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37995592

ABSTRACT

Dissolved oxygen (DO) concentration is an important index of ocean systems. In this study, spatiotemporal variations in DO were analyzed in the northern Gulf of Mexico (NGM) for the period of 1992-2017. Temporal variation involves annual, monthly, and seasonal variations. The spatial scope ranged from the sea surface to 1000 m depth. The results show that: (1) DO decreased from 1992 to 2017 with a brief increase; (2) clear seasonal variation characteristics of DO were presented, and the seasonal average DO was relatively low in summer; (3) the monthly average trends of sea surface DO in different years were relatively consistent; and (4) with increasing water depth from seawater surface to 1000 m, the average DO of 1992 to 2017 tended to decrease and then increase. The results aim at shedding some light on the assessment of DO change in the NGM over the past quarter century.


Subject(s)
Seawater , Water , Gulf of Mexico , Seasons , Oxygen/analysis
2.
Stem Cell Res ; 72: 103201, 2023 10.
Article in English | MEDLINE | ID: mdl-37856927

ABSTRACT

In this study, fibroblasts were harvested and isolated from a healthy 14-year-old male donor and reprogrammed with four Yamanaka factors containing Oct3/4, Sox2, Klf4 and c-Myc to generate human induced pluripotent stem cell (iPSC) lines. The resulting iPSCs were integration-free, expressed normal karyotype, displayed pluripotency markers, and have been demonstrated to differentiate into cells with three germ layer. And the iPSCs were further differentiated to chondrosphere in vivo. The models could be used to test multiple differentiation protocols and also as a control for screening drugs and studying cartilage related disease.


Subject(s)
Induced Pluripotent Stem Cells , Male , Humans , Adolescent , Induced Pluripotent Stem Cells/metabolism , Cell Differentiation , Fibroblasts/metabolism , Cells, Cultured , Proto-Oncogene Proteins c-myc/genetics , Cellular Reprogramming
3.
Front Genet ; 14: 1218408, 2023.
Article in English | MEDLINE | ID: mdl-37693314

ABSTRACT

Gliomas are highly heterogeneous and aggressive. Malignant cells in gliomas can contact normal neurons through a synapse-like structure (called neuron-to-glioma synapse, NGS) to promote their proliferation, but it is unclear whether NGS gene expression and regulation show species- and tumor-specificity. This question is important in that many anti-cancer drugs are developed upon mouse models. To address this question, we conducted a pan-glioma analysis using nine scRNA-seq datasets from humans and mice. We also experimentally validated the key element of our methods and verified a key result using TCGA datasets of the same glioma types. Our analyses revealed that NGS gene expression and regulation by lncRNAs are highly species- and tumor-specific. Importantly, simian-specific lncRNAs are more involved in NGS gene regulation than lncRNAs conserved in mammals, and transgenic mouse gliomas have little in common with PDX mouse models and human gliomas in terms of NGS gene regulation. The analyses suggest that simian-specific lncRNAs are a new and rich class of potential targets for tumor-specific glioma treatment, and provide pertinent data for further experimentally and clinically exmining the targets.

4.
ACS Nano ; 17(15): 14775-14791, 2023 08 08.
Article in English | MEDLINE | ID: mdl-37477584

ABSTRACT

Oral administration of probiotics is a promising method to alleviate inflammatory bowel diseases (IBDs). However, gastrointestinal environmental sensitivity and inferior intestinal colonization of probiotics hinder the alleviation effect. Here, we developed a simple yet effective modified prebiotic-based "shield" (Fe-TA@mGN) composed of an Fe3+-tannic acid cross-linking network and carboxymethylated ß-glucan for arming Escherichia coli Nissle 1917 (EcN@Fe-TA@mGN). The Fe-TA@mGN "shield" not only acted as a dynamic barrier to enhance the gastrointestinal stress resistance ability of EcN but also aided the intestinal colonization of EcN as well as synergized with EcN for the alleviation of dextran sulfate sodium (DSS) induced colitis. More specifically, with the protection of the Fe-TA@mGN "shield", the survival rate of armed EcN could be up to ∼1720 times higher than that of bare EcN after exposure to simulated gastric fluid. Excitingly, the intestinal retention rate of EcN@Fe-TA@mGN was as high as 47.54 ± 6.06% at 16 h post-administration, while almost all bare EcNs were excreted out at 8 h post-administration. With all of the aforementioned attributes, EcN@Fe-TA@mGN efficiently alleviated colitis, verified by the repair of the intestinal barrier and the attenuation of inflammation. Moreover, for EcN@Fe-TA@mGN, mGN synergized with EcN to positively modulate gut microbiota and promote the production of short-chain fatty acids (SCFAs, especially for butyric acid, a primary source for maintaining intestinal health), both of which would further advance the alleviation of colitis. We envision that the strategy developed here will inspire the exploitation of various prebiotics to arm probiotics for the effective alleviation of IBD.


Subject(s)
Colitis , Probiotics , Humans , Colitis/chemically induced , Colitis/drug therapy , Intestines , Prebiotics , Probiotics/pharmacology , Probiotics/therapeutic use
5.
Insects ; 14(6)2023 Jun 08.
Article in English | MEDLINE | ID: mdl-37367353

ABSTRACT

Spodoptera frugiperda (J. E. Smith), commonly known as the fall armyworm (FAW), causes significant damage to many different crop species. In this study, age-stage, two-sex life table analysis was used to investigate the effects of sublethal concentrations of emamectin benzoate and chlorantraniliprole on FAW development and reproduction. In the F0 generation, exposure to emamectin benzoate and chlorantraniliprole significantly impacted the duration of FAW, thus prolonging the development duration of each instar, but not the prepupal stage. Furthermore, the weight of FAW pupae was significantly reduced by emamectin benzoate at LC25 and chlorantraniliprole at LC25 in the F0 generation. With respect to fecundity, emamectin benzoate and chlorantraniliprole significantly reduced fecundity in the F0 generation. In the F1 generation, emamectin benzoate at LC10 had no significant effect on the preadult or adult stages, whereas LC25 significantly shortened the preadult period. The preadult and adult stages of FAW exposed to chlorantraniliprole at LC10 and LC25 were significantly prolonged. Furthermore, emamectin benzoate had no significant effect on the pupal weight of the F1 generation. Chlorantraniliprole had no significant effect at LC10, but significant reduced pupal weight occurred at LC25 in the F1 generation. With respect to fecundity, emamectin benzoate significantly reduced fecundity in the F1 generation. Interestingly, chlorantraniliprole significantly increased fecundity in the F1 generation, which could promote population growth and pest resurgence. These findings have important implications for the integrated pest management of FAW and provide a reference for the more effective control of FAW.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 300: 122773, 2023 Nov 05.
Article in English | MEDLINE | ID: mdl-37244025

ABSTRACT

Light-emitting perovskite quantum dots (PeQDs) are extensively investigated owing to their evident merits. However, it is still a challenge to adjust their intrinsic emissions and enhance their thermal stability to achieve full-color highly emissive QD-based light-emitting diodes (QLEDs), especially blue QLEDs. Herein, we demonstrate an effective strategy to fundamentally stabilize the crystal structure of CsPbBr3 QDs by codoping Na+ and Cu2+ ions, which are designed to substitute Cs+ (A sites) and Pb2+ (B sites), respectively. It is found out that the codoping metal ions have significantly improved the thermal stability and the optical properties of the QDs. 40% of the emission intensity can be remained after 8 thermal cycles (20-120 °C) for CsPbBr3: Na+/Cu2+ QDs, whilst less than 10% is maintained for undoped CsPbBr3 QDs. Accordingly, stable blue QLEDs are packed by CsPbBr3: Na+/Cu2+ QDs. Strong electroluminescence with the maximum luminance of 7161 cd m-2 and low turn-on voltage of 2.4 V are realized. The CIE coordinates are tuned from green (0.10, 0.74) to blue (0.17, 0.25) via Na+ and Cu2+ codoping. The maximum external quantum efficiency (EQEmax) is obtained as 4.52% for PeLEDs based on codoped QDs. The proposed metal ions A and B sites dual substitution strategy guarantees PeQDs as an extremely promising prospect in potential applications as high-resolution displays and high-quality lightings.


Subject(s)
Quantum Dots , Excipients , Ions , Oxides
7.
Small ; 19(39): e2303254, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37226363

ABSTRACT

Perovskite solar cells (PSCs) based on the SnO2 electron transport layer (ETL) have achieved remarkable photovoltaic efficiency. However, the commercial SnO2 ETLs show various shortcomings. The SnO2 precursor is prone to agglomeration, resulting in poor morphology with numerous interface defects. Additionally, the open circuit voltage (Voc ) would be constrained by the energy level mismatch between the SnO2 and the perovskite. And, few studies designed SnO2 -based ETLs to promote crystal growth of PbI2 , a crucial prerequisite for obtaining high-quality perovskite films via the two-step method. Herein, we proposed a novel bilayer SnO2 structure that combined the atomic layer deposition (ALD) and sol-gel solution to well address the aforementioned issues. Due to the unique conformal effect of ALD-SnO2 , it can effectively modulate the roughness of FTO substrate, enhance the quality of ETL, and induce the growth of PbI2 crystal phase to develop the crystallinity of perovskite layer. Furthermore, a created built-in field of the bilayer SnO2 can help to overcome the electron accumulation at the ETL/perovskite interface, leading to a higher Voc and fill factor. Consequently, the efficiency of PSCs with ionic liquid solvent increases from 22.09% to 23.86%, maintaining 85% initial efficiency in a 20% humidity N2 environment for 1300 h.

8.
ACS Appl Mater Interfaces ; 15(13): 16818-16827, 2023 Apr 05.
Article in English | MEDLINE | ID: mdl-36966414

ABSTRACT

State-of-the-art high-performance perovskite solar cells are mainly based on formamidinium (FA)-dominated perovskites because of their narrow band gap and remarkable thermal resistance. However, photoactive α-FAPbI3 is prone to transit to the photoinactive phase, and pioneering phase stabilization strategies can induce undesirable band gap broadening or phase segregation, seriously restricting the efficiency and long-term stability of the resultant photovoltaics. Herein, a small molecule of ammonium acetate (NH4Ac) was introduced as an additive in a modified ripening method to fabricate component-pure α-FAPbI3. Owing to the strong interaction between NH4Ac and PbI2, FAI via Pb-O coordination, and N-H···N hydrogen bonding, vertically oriented perovskites with relaxed crystal strain were first generated, which were fully converted to α-FAPbI3 in a further ripening process. The NH4Ac was fully volatized after the perovskite formation, resulting in component-pure α-FAPbI3 with a band gap of 1.48 eV and remarkable stability under light illumination. Ultimately, a champion device efficiency of above 21% was obtained based on the component-pure α-FAPbI3 and over 95% of the initial efficiency can be maintained after 1000 h of aging.

9.
Chem Biodivers ; 20(1): e202200985, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36433761

ABSTRACT

Twelve new clerodane diterpenoids named callicarpanes A-L (1-12), together with eight known compounds (13-20), were isolated from Callicarpa integerrima. Their structures were determined by comprehensive spectroscopic data. The calculated chemical shifts were used to identify relative configurations using DP4+ analysis. The absolute configurations (AC) were assigned based on quantum chemical calculations and X-ray single-crystal diffraction methods. Compounds 1, 3, 5, 9, 10, 12, 15, 16, and 19 showed significant inhibitory activity for NLRP3 inflammasome activation, with the IC50 against lactate dehydrogenase (LDH) release ranging from 0.08 to 4.78 µM. Further study revealed that compound 10 repressed IL-1ß secretion and caspase-1 maturation in J774A.1 cell as well as blocked macrophage pyroptosis.


Subject(s)
Callicarpa , Diterpenes, Clerodane , Diterpenes, Clerodane/pharmacology , Diterpenes, Clerodane/chemistry , Inflammasomes , NLR Family, Pyrin Domain-Containing 3 Protein , Callicarpa/chemistry , Macrophages
10.
J Pathol ; 259(4): 376-387, 2023 04.
Article in English | MEDLINE | ID: mdl-36573552

ABSTRACT

For stage III colorectal cancer (CRC) patients with a high risk of recurrence, intensified adjuvant chemotherapy can improve overall survival. We aimed to develop a circulating tumor DNA (ctDNA) methylation marker model for predicting the relapse risk of stage III CRC patients. Differentially methylated markers identified between 53 normal mucosa samples and 165 CRC tissue samples, as well as between plasma samples from 75 stage I/II (early-stage) CRC patients and 55 stage IV (late-stage) CRC patients, were analyzed using Student's t-tests. The overlapping methylation markers shared by plasma and tissue samples were used to establish a methylation marker model to evaluate the tumor burden in the peripheral blood of CRC patients using the random forest method. This model was verified in the validation cohort (n = 44) and then applied to predict recurrence risk in 50 stage III CRC patients and monitor the clinical disease course in serial samples from four CRC patients. We built a five-marker-based ctDNA methylation model that had high sensitivity (84.21%) and specificity (84%) in identifying late-stage CRC in a validation cohort containing 24 stage I/II CRC patients and 20 stage IV CRC patients. The model achieved high sensitivity (87.5%) and specificity (94.12%) in predicting tumor relapse in an independent cohort of 50 stage III CRC patients and could be an independent recurrence risk factor for stage III patients [Hazard ratio (HR), 60.4; 95% confidence interval (CI): 7.68-397; p = 9.73e-5]. Analysis of serial blood samples of CRC showed that the model could monitor disease relapse earlier than imaging examination and serum carcinoembryonic antigen (CEA) and so may provide an opportunity for the early adjustment of therapeutic strategies. Moreover, the model could potentially monitor the clinical course and treatment response dynamically. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Subject(s)
Cell-Free Nucleic Acids , Colorectal Neoplasms , Humans , Biomarkers, Tumor/genetics , DNA Methylation , Neoplasm Recurrence, Local/genetics , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Risk Assessment , Cell-Free Nucleic Acids/genetics
11.
Soft comput ; 27(7): 3921-3939, 2023.
Article in English | MEDLINE | ID: mdl-36407893

ABSTRACT

At present, the COVID-19 epidemic is still spreading at home and abroad, and the foreign exchange market is highly volatile. From financial institutions to individual investors, foreign exchange asset allocation has become important contents worthy of attention. However, most intelligent optimization algorithms (hereinafter IOAS) adopt the existing data and ignore the forecasted one in the foreign exchange portfolio allocation, which will result in a huge difference between portfolio allocation and actual demand; at the same time, many IOAS are less adaptable and have lower optimization ability in portfolio problems. To solve the aforementioned problems, this paper first proposed a DETS based on hybrid tabu search and differential evolution algorithms (DEAs), which has excellent optimization ability. Subsequently, the DETS algorithm was applied to support vector machine (SVM) model. Experiments show that, compared with other algorithms, the MAE and RMSE obtained by using DETS optimization parameters are reduced by at least 3.79 and 1.47%, while the CTR is improved by at least 2.19%. Then combined with the DETS algorithm and Pareto sorting theory, an algorithm suitable for multi-objective optimization was further proposed, named NSDE-TS. Finally, by applying NSDE-TS algorithm, the optimal foreign exchange portfolio is acquired. The empirical analysis shows that the Pareto front obtained by this algorithm is better than that of NSGA-II. Since the lower the uniformity index and convergence index, the stronger the optimization performance of the corresponding algorithm, compared with NSGA-II, its uniformity and convergence index decreased by 15.7 and 39.6%.

12.
Front Oncol ; 12: 827811, 2022.
Article in English | MEDLINE | ID: mdl-35646690

ABSTRACT

Advanced adenoma (AA) holds a significantly increased risk for progression to colorectal cancer (CRC), and we developed a noninvasive DNA methylation prediction model to monitor the risk of AA progression to CRC. We analyzed the differential methylation markers between 53 normal mucosa and 138 CRC tissues, as well as those in cfDNA (cell-free DNA) between 59 AA and 68 early-stage CRC patients. We screened the overlapping markers between tissue DNA and cfDNA for model variables and optimized the selected variables. Then, we established a cfDNA methylation prediction model (SDMBP model) containing seven methylation markers that can effectively discriminate early-stage CRC and AA in the training and validation cohorts, and the AUC (area under the curve) reached 0.979 and 0.918, respectively. Our model also reached high precision (AUC=0.938) in detecting advanced CRC (stage III/IV) and presented better performance than serum CEA and CA199 in screening CRC. The cd-score of the SDMBP model could also robustly predict the TNM stage of CRC. Overall, our SDMBP model can monitor the malignant progression from AA to CRC, and may provide a noninvasive monitoring method for high-risk populations with AA.

13.
PLoS One ; 16(6): e0252244, 2021.
Article in English | MEDLINE | ID: mdl-34086735

ABSTRACT

The purposes are to improve the server deployment capability under Mobile Edge Computing (MEC), reduce the time delay and energy consumption of terminals during task execution, and improve user service quality. After the server deployment problems under traditional edge computing are analyzed and researched, a task resource allocation model based on multi-stage is proposed to solve the communication problem between different supporting devices. This model establishes a combined task resource allocation and task offloading method and optimizes server execution by utilizing the time delay and energy consumption required for task execution and comprehensively considering the restriction processes of task offloading, partition, and transmission. For the MEC process that supports dense networks, a multi-hybrid intelligent algorithm based on energy consumption optimization is proposed. The algorithm converts the original problem into a power allocation problem via a heuristic model. Simultaneously, it determines the appropriate allocation strategy through distributed planning, duality, and upper bound replacement. Results demonstrate that the proposed multi-stage combination-based service deployment optimization model can solve the problem of minimizing the maximum task execution energy consumption combined with task offloading and resource allocation effectively. The algorithm has good performance in handling user fairness and the worst-case task execution energy consumption. The proposed hybrid intelligent algorithm can partition tasks into task offloading sub-problems and resource allocation sub-problems, meeting the user's task execution needs. A comparison with the latest algorithm also verifies the model's performance and effectiveness. The above results can provide a theoretical basis and some practical ideas for server deployment and applications under MEC.


Subject(s)
Cloud Computing/standards , Computers/standards , Investments/standards , Resource Allocation/methods , Resource Allocation/standards , Algorithms
14.
RSC Adv ; 10(54): 32561-32568, 2020 Sep 01.
Article in English | MEDLINE | ID: mdl-35516479

ABSTRACT

Composites of carbon and magnetic metal can overcome the eddy current effects and high density of traditional magnetic metals based on their synergistic loss mechanism and tunable electromagnetic properties. Herein, Fe@carbon fiber particles were synthesized by growing iron nanoflakes on the surface of carbon fibers via in situ reduction. The surface morphology, lattice structure and element composition of the synthesized Fe@carbon fibers were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy disperse spectroscopy (EDS) respectively. Based on these qualitative analyses, a possible growth mechanism was proposed for guide production. In order to investigate their electromagnetic absorbing properties, electromagnetic parameters of Fe@carbon fibers-paraffin composites have been evaluated by coaxial reflection/transmission technique. The Fe@carbon fibers-paraffin composites containing different particle contents were prepared to clarify the optimum material ratio. The results showed that the composite loaded with 30 wt% carbon fibers@Fe particles exhibited the most prominent microwave absorption, with strong absorption (maximum reflection loss of -39.8 dB), effective absorption bandwidth (2.9 GHz) and small thickness (1.5 mm).

15.
Environ Sci Pollut Res Int ; 27(4): 4236-4245, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31828699

ABSTRACT

Mercury pollution is a global problem and of particular concern in high emissions areas, such as China. We studied the migratory Kentish Plover, Charadrius alexandrinus, which breeds in coastal northern/central China and the inland Qinghai Lake, and the White-faced Plover C. dealbatus, a year-round resident of coastal southern China. We measured total mercury (THg) concentrations in feather and blood samples of breeding females. We expected low levels at the remote Qinghai Lake, but we found instead that feather THg concentrations were highest there (3.89 ± 1.53 [SD] µg/g DW [n = 34]; compared to 1.29 ± 0.61 µg/g of Kentish Plover elsewhere [n = 35] and 2.08 ± 1.45 µg/g for White-faced Plover [n = 56]), a result is consistent over 2 years. When including only coastal populations in the analysis, there were no differences in THg concentrations between the two species, although White-faced Plover had more variation. Feather THg concentrations for the coastal populations are similar to other studies on plovers and sandpipers globally, with most birds under the threshold of adverse effects (3 µg/g, an estimate that itself may be too low). Nevertheless, the Qinghai Kentish Plover population has mean feather concentrations above this threshold, indicating high exposure during the nonbreeding season, and some individuals have extreme values (e.g., a bird with a blood level of 7.63 µg/g DW from Zhanjiang, south China), so further research and monitoring are needed.


Subject(s)
Charadriiformes , Environmental Monitoring , Environmental Pollutants/analysis , Mercury/analysis , Animals , China , Feathers/chemistry , Female
16.
BMC Evol Biol ; 19(1): 135, 2019 06 27.
Article in English | MEDLINE | ID: mdl-31248363

ABSTRACT

BACKGROUND: Speciation with gene flow is an alternative to the nascence of new taxa in strict allopatric separation. Indeed, many taxa have parapatric distributions at present. It is often unclear if these are secondary contacts, e.g. caused by past glaciation cycles or the manifestation of speciation with gene flow, which hampers our understanding of how different forces drive diversification. Here we studied genetic, phenotypic and ecological aspects of divergence in a pair of incipient shorebird species, the Kentish (Charadrius alexandrinus) and the White-faced Plovers (C. dealbatus), shorebirds with parapatric breeding ranges along the Chinese coast. We assessed divergence based on molecular markers with different modes of inheritance and quantified phenotypic and ecological divergence in aspects of morphometric, dietary and climatic niches. RESULTS: Our integrative analyses revealed small to moderate levels of genetic and phenotypic distinctiveness with symmetric gene flow across the contact area at the Chinese coast. The two species diverged approximately half a million years ago in dynamic isolation with secondary contact occurring due to cycling sea level changes between the Eastern and Southern China Sea in the mid-late Pleistocene. We found evidence of character displacement and ecological niche differentiation between the two species, invoking the role of selection in facilitating divergence despite gene flow. CONCLUSION: These findings imply that ecology can indeed counter gene flow through divergent selection and thus contributes to incipient speciation in these plovers. Furthermore, our study highlights the importance of using integrative datasets to reveal the evolutionary history and assist the inference of mechanisms of speciation.


Subject(s)
Charadriiformes/genetics , Ecological and Environmental Phenomena , Genetic Speciation , Phenotype , Animals , China , Gene Flow , Phylogeny
17.
Article in Chinese | MEDLINE | ID: mdl-20120870

ABSTRACT

OBJECTIVE: To observe expression of stathmin gene in laryngeal squamous cell carcinoma (LSCC) and relation between expression of stathmin gene and occurrence and development of LSCC. METHOD: The expression of the stathmin gene was determined in 35 LSCC of specimens and 18 normal laryngeal tissues (NLT) of specimens by in situ hybridization with Digoxigenin labeled probe of stathmin mRNA. RESULT: Expression of stathmin gene was observed in 35 cases of laryngeal squamous cell carcinoma tissue (positive rate, 69%) and positive signal was observed in both cytoplasm and nuclear. Among 18 cases of normal tissue, only 6 showed weak positive signal. There was significant difference in expression of stathmin gene between laryngeal squamous cell carcinoma tissue and normal tissue. CONCLUSION: Expression of stathmin gene may play a key role in the pathogenesis and development of laryngeal squamous cell carcinoma. It may be a very important biotherapy target in the treatment of laryngeal squamous cell carcinoma.


Subject(s)
Carcinoma, Squamous Cell/genetics , Laryngeal Neoplasms/genetics , Stathmin/metabolism , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/pathology , Gene Expression , Humans , Laryngeal Neoplasms/metabolism , Laryngeal Neoplasms/pathology , RNA, Messenger/genetics , Stathmin/genetics
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