Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 445
Filtrar
1.
Mar Pollut Bull ; 179: 113666, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35500373

RESUMO

Oil spill discharges from operational maritime activities like ships, oil rigs and other structures, leaking pipelines, as well as natural hydrocarbon seepage pose serious threats to marine ecosystems and fisheries. Satellite synthetic aperture radar (SAR) is a unique microwave instrument for marine oil spill monitoring, as it is not dependent on weather or sunlight conditions. Existing SAR oil spill detection approaches are limited by algorithm complexity, imbalanced data sets, uncertainties in selecting optimal features, and relatively slow detection speed. To overcome these restrictions, a fast and effective SAR oil spill detection method is presented, based a novel deep learning model, named the Faster Region-based Convolutional Neural Network (Faster R-CNN). This approach is capable of achieving fast end-to-end oil spill detection with reasonable accuracy. A large data set consisting of 15,774 labeled oil spill samples derived from 1786C-band Sentinel-1 and RADARSAT-2 vertical polarization SAR images is used to train, validate and test the Faster R-CNN model. Our experimental results show that the proposed method exhibits good performance for detection of oil spills with wide swath SAR imagery. The Precision and Recall metrics are 89.23% and 89.14%, respectively. The average Precision is 92.56%. The effects of environmental conditions and sensor parameters on oil spill detection are analyzed. The expected detection results are obtained when wind speeds and incidence angles are between 3 m/s and 10 m/s, and 21° and 45°, respectively. Furthermore, the computer runtime for oil spill detection is less than 0.05 s for each full SAR image, using a workstation with NVIDIA GeForce RTX 3090 GPU. This suggests that the present approach has potential for applications that require fast oil spill detection from spaceborne SAR images.

2.
Biosci Rep ; 42(5)2022 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-35521959

RESUMO

BACKGROUND: Exploration of serum biomarkers for early detection of upper gastrointestinal cancer is required. Here, we aimed to evaluate the diagnostic potential of serum desmoglein-2 (DSG2) in patients with esophageal squamous cell carcinoma (ESCC) and esophagogastric junction adenocarcinoma (EJA). METHODS: Serum DSG2 levels were measured by enzyme-linked immunosorbent assay (ELISA) in 459 participants including 151 patients with ESCC, 96 with EJA, and 212 healthy controls. Receiver operating characteristic (ROC) curves were used to evaluate diagnostic accuracy. RESULTS: Levels of serum DSG2 were significantly higher in patients with ESCC and EJA than those in healthy controls (P<0.001). Detection of serum DSG2 demonstrated an area under the ROC curve (AUC) value of 0.724, sensitivity of 38.1%, and specificity of 84.8% for the diagnosis of ESCC in the training cohort, and AUC 0.736, sensitivity 58.2%, and specificity 84.7% in the validation cohort. For diagnosis of EJA, measurement of DSG2 provided a sensitivity of 29.2%, a specificity of 90.2%, and AUC of 0.698. Similar results were observed for the diagnosis of early-stage ESCC (AUC 0.715 and 0.722, sensitivity 36.3 and 50%, and specificity 84.8 and 84.7%, for training and validation cohorts, respectively) and early-stage EJA (AUC 0.704, sensitivity 44.4%, and specificity 86.9%). Analysis of clinical data indicated that DSG2 levels were significantly associated with patient age and histological grade in ESCC (P<0.05). CONCLUSION: Serum DSG2 may be a diagnostic biomarker for ESCC and EJA.


Assuntos
Adenocarcinoma , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Adenocarcinoma/diagnóstico , Biomarcadores Tumorais , Desmogleína 2 , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/diagnóstico , Carcinoma de Células Escamosas do Esôfago/patologia , Junção Esofagogástrica/patologia , Humanos
3.
Sci Total Environ ; 833: 155208, 2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35417724

RESUMO

Cadmium (Cd) could reduce abnormal cell morphology and membrane permeability, however, there are few studies on the detoxification of Cd-reduced cell membrane toxicity. In the present study, we firstly studied the effects of zinc chloride (ZnCl2), n-acetyl-L-cysteine (NAC), and calcium/calmodulin dependent protein kinase II inhibitor (KN93) on cell membrane permeability, respectively; then, we studied the inhibitory effects of ZnCl2, NAC, and KN93 on Cd2+-induced abnormal cell membrane permeability by scanning electrochemical microscopy (SECM) scanning imaging, transverse scanning curve and DPV technology. Our results showed that 10 µmol·L-1 ZnCl2, 0.5 mmol·L-1 NAC and 5 µmol·L-1 KN93 could significantly improve the activity of MCF-7 cells, while did not destroy the cell morphology and membrane permeability. 0.5 mmol·L-1 NAC and 5 µmol·L-1 KN93 could significantly inhibit the effects of Cd2+ on the morphology and membrane permeability of MCF-7 cells (p < 0.01). 10 µmol·L-1 ZnCl2 could significantly inhibit the effect of Cd on the membrane permeability of MCF-7 cells, however, it cannot completely eliminate the morphological changes of MCF-7 cells caused by Cd2+. The results of cell activity experiment showed that 10 µmol·L-1 ZnCl2, 0.5 mmol·L-1 NAC and 5 µmol·L-1 KN93 could inhibit the effect of Cd2+ on the activity of MCF-7 cells. By comparing the inhibitory effects of ZnCl2, NAC and KN93 on Cd2+- induced cytotoxicity, 5 µmol·L-1 KN93 had the robust effect on the maintenance of MCF-7 cell morphology and cell membrane integrity. Our research provided evidence on Zn supplement, NAC as antioxidant drugs, and KN93 as special inhibitor for the detoxification of Cd2+-reduced abnormal cell morphology and membrane permeability.

4.
Front Oncol ; 12: 852803, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35387121

RESUMO

Background: Necroptosis is crucial for organismal development and pathogenesis. To date, the role of necroptosis in skin cutaneous melanoma (SKCM) is yet unveiled. In addition, the part of melanin pigmentation was largely neglected in the bioinformatic analysis. In this study, we aimed to construct a novel prognostic model based on necroptosis-related genes and analysis the pigmentation phenotype of patients to provide clinically actionable information for SKCM patients. Methods: We downloaded the SKCM data from the TCGA and GEO databases in this study and identified the differently expressed and prognostic necroptosis-related genes. Patients' pigmentation phenotype was evaluated by the GSVA method. Then, using Lasso and Cox regression analysis, a novel prognostic model was constructed based on the intersected genes. The risk score was calculated and the patients were divided into two groups. The survival differences between the two groups were compared using Kaplan-Meier analysis. The ROC analysis was performed and the area under curves was calculated to evaluate the prediction performances of the model. Then, the GO, KEGG and GSEA analyses were performed to elucidate the underlying mechanisms. Differences in the tumor microenvironment, patients' response to immune checkpoint inhibitors (ICIs) and pigmentation phenotype were analyzed. In order to validate the mRNA expression levels of the selected genes, quantitative real-time PCR (qRT-PCR) was performed. Results: Altogether, a novel prognostic model based on four genes (BOK, CD14, CYLD and FASLG) was constructed, and patients were classified into high and low-risk groups based on the median risk score. Low-risk group patients showed better survival status. The model showed high accuracy in the training and the validation cohort. Pathway and functional enrichment analysis indicated that immune-related pathways were differently activated in the two groups. In addition, immune cells infiltration patterns and sensitivity of ICIs showed a significant difference between patients from two risk groups. The pigmentation score was positively related to the risk score in pigmentation phenotype analysis. Conclusion: In conclusion, this study established a novel prognostic model based on necroptosis-related genes and revealed the possible connections between necroptosis and melanin pigmentation. It is expected to provide a reference for clinical treatment.

5.
COPD ; 19(1): 118-124, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35385369

RESUMO

OBJECTIVE: We aimed to establish an easy-to-use screening questionnaire with risk factors and suspected symptoms of COPD for primary health care settings. METHODS: Based on a nationwide epidemiological study of pulmonary health among adults in mainland China (China Pulmonary Health, CPH study) between 2012 and 2015, participants ≥40 years who completed the questionnaire and spirometry tests were recruited and randomly divided into development set and validation set by the ratio of 2:1. Parameters including sex, age, BMI, residence, education, smoking status, smoking pack-years, biomass exposure, parental history of respiratory diseases and daily respiratory symptoms were initially selected for the development of scoring system. Receiver operating characteristic (ROC) curve, area under curve (AUC), positive and negative predictive values were calculated in development set and validation set. RESULTS: After random split by 2:1 ratio, 22443 individuals were assigned to development set and 11221 to validation set. Ten variables were significantly associated with COPD independently in development set after a stepwise selection by multivariable logistic model and used to develop scoring system. The scoring system yielded good discrimination, as measured by AUC of 0.7737, and in the validation set, the AUC was 0.7711. When applying a cutoff point of ≥16, the sensitivity in development set was 0.69 (0.67 - 0.71); specificity 0.72 (0.71 - 0.73), PPV 0.25 (0.24 - 0.26) and NPV 0.94 (0.94 - 0.95). CONCLUSION: We developed and validated a comprehensive screening questionnaire, COPD-CPHS, with good discrimination. The score system still needs to be validated by large cohort in the future.Supplemental data for this article is available online at https://doi.org/10.1080/15412555.2022.2042504 .


Assuntos
Doença Pulmonar Obstrutiva Crônica , Adulto , Área Sob a Curva , China/epidemiologia , Estudos Epidemiológicos , Humanos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Curva ROC , Espirometria , Inquéritos e Questionários
6.
RSC Adv ; 12(3): 1777-1787, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35425162

RESUMO

The brittle fracture of polyurethane elastomer (PUE) under high-speed impact limits its application in high-speed impact protection. Here, based on the principle of free radical polymerization and π-π conjugation, composite nanoparticles (C-MWCNTs) are prepared by copolymerization of epoxy group ionic liquid (GVIMBr) and divinylbenzene (DVB) on MWCNTs using DVB as a linker. C-MWCNTs participate in the curing process of PUE through epoxy groups to form in situ crosslinked C-MWCNTs/PUE, which improves the energy absorption and high-speed impact properties of PUE. Compared with neat PUE, the maximum compressive strength and energy absorbed by C-MWCNTs/PUE are increased by 46.3% and 23.6%, respectively. By observing the microsurface and fracture morphology of C-MWCNTs/PUE, the relationship between macroscopic mechanical properties and microstructure is constructed. The improvement of the mechanical properties of the C-MWCNTs/PUE is attributed to the interfacial interaction and homogeneous dispersion of the C-MWCNTs in the PUE matrix. These microscopic effects are caused by the good compatibility between GVIMBr and PUE matrix and the synergistic enhancement between GVIMBr and MWCNTs.

7.
Artigo em Inglês | MEDLINE | ID: mdl-35319279

RESUMO

Objective: To compare the outcomes of secondary minimally invasive pyeloplasty (MIP) versus primary MIP for the patients with ureteropelvic junction obstruction (UPJO). Materials and Methods: We searched all the literature of PubMed, Web of Science, EMBASE, and Cochrane Library comparing secondary MIP and primary MIP and performed a systematic review and meta-analysis. Results: We included 15 studies involving 1637 patients with 1371 in the primary MIP group and 266 in the secondary MIP group. There were no significant differences in length of hospital stays, and the risk of hematuria, urinary tract infection, intestinal obstruction, stent complications, and overall complications (P > .05). Comparing with the secondary MIP group, the primary MIP group has shorter operative time (mean difference [MD] = -36.91 minutes, 95% confidence interval [CI]: -50.21 to -23.62, P < .00001), less estimated blood loss (MD = -16.70 mL, 95% CI: -31.60 to -1.80, P = .03), lower risk of urinary leakage and injury of blood vessel (relative risk [RR] = 0.32, 95% CI: 0.11-0.93, P = .04) (RR = 0.10, 95% CI: 0.02-0.61, P = .01), and higher success rate (RR = 1.07, 95% CI: 1.02-1.11, P = .003). The robot-assisted pyeloplasty is superior to the laparoscopic pyeloplasty in controlling the amount of blood loss in the secondary operation. Conclusions: Considering the poorer outcomes of secondary surgery, we believe that special attention should be paid to not missing crossing vessels, and it would be more prudent to perform a more definitive procedure with pyeloplasty instead of endopyelotomy for primary UPJO.

8.
Micromachines (Basel) ; 13(3)2022 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35334726

RESUMO

Self-oscillating systems based on thermally responsive polymer materials can realize heat-mechanical transduction in a steady ambient temperature field and have huge application potential in the field of micro-active machines, micro-robotics and energy harvesters. Recently, experiments have found that a torus on a hot surface can rotate autonomously and continuously, and its rotating velocity is determined by the competition between the thermally induced driving moment and the sliding friction moment. In this article, we theoretically study the self-sustained rotation of a hollow torus on a hot surface and explore the effect of the radius ratio on its rotational angular velocity and energy efficiency. By establishing a theoretical model of heat-driven self-sustained rotation, its analytical driving moment is derived, and the equilibrium equation for its steady rotation is obtained. Numerical calculation shows that with the increase in the radius ratio, the angular velocity of its rotation monotonously increases, while the energy efficiency of the self-rotating hollow torus motor first increases and then decreases. In addition, the effects of several system parameters on the angular velocity of it are also extensively investigated. The results in this paper have a guiding role in the application of hollow torus motor in the fields of micro-active machines, thermally driven motors and waste heat harvesters.

9.
Biology (Basel) ; 11(3)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35336785

RESUMO

In zebrafish, RNA-guided endonucleases such as Cas9 have enabled straightforward gene knockout and the construction of reporter lines or conditional alleles via targeted knockin strategies. However, the performance of another commonly used CRISPR system, Cas12a, is significantly limited due to both the requirement of delivery as purified protein and the necessity of heatshock of injected embryos. To explore the potential of CRISPR/Cas12a-mediated genome editing and simplify its application in zebrafish, we took advantage of the recently reported mRNA-active ErCas12a and investigated its efficacy for the knockin of large DNA fragments, such as fluorescent reporter genes. For knockin via either microhomology-mediated end joining (MMEJ) or non-homologous end joining (NHEJ) pathways, ErCas12a-injected embryos with a brief heatshock displayed comparable knockin efficiency with Cas9 injection. Through the fusion of T5 exonuclease (T5exo) to the N-terminus of ErCas12a (T5exo-ErCas12a), we further demonstrated high efficiency gene knockout and knockin at a normal incubation temperature, eliminating the embryo-damaging heatshock step. In summary, our results demonstrate the feasibility of ErCas12a- and T5exo-ErCas12a-mediated genome manipulation under simplified conditions, and further expand the genome editing toolbox for various applications in zebrafish.

10.
Org Biomol Chem ; 20(11): 2227-2232, 2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-35237774

RESUMO

Herein is reported the first example of ring opening and skeletal reconstruction of 3-vinyl benzofuranone-chromones 1 as versatile synthons, which can react with ammonia or primary aliphatic amines as binucleophiles, for the eco-friendly and atom-economical synthesis of diverse and functionalized 2-pyridones 3 with potential biological activity in good to excellent yields (77-93%). When using optically active 1,2-diphenylethylenediamine 2 as the binucleophile, the in situ generated 2-pyridone intermediates are successfully transformed to novel optically active functionalized imidazoline derivatives 4 with high efficiency (up to 87% yield). In particular, this is the first report on the catalyst-free intramolecular cyclization occurring between an amide and a primary aliphatic amine for the construction of imidazoline molecules.


Assuntos
Cromonas , Imidazolinas , Aminas , Catálise , Piridonas
11.
Sci Rep ; 12(1): 1808, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35110569

RESUMO

Epidemiological studies have indicated that natural disasters have important impacts on ischemic stroke. This study determined the associations between natural disasters and the incidence and prevalence of ischemic stroke at the global level. A 28-year ecological trend study was performed to estimate worldwide changes in the incidence and prevalence of ischemic stroke and their associations with natural disasters by analyzing data from 193 countries. Quantum geographic information system-based visualization and multivariable linear regression were used. Changes in the incidence and prevalence of ischemic stroke, as well as disaster occurrence, varied among the different regions over the past 28 years (p < 0.001). Multiple linear regression revealed an independent and positive association between disaster occurrence and the incidence of ischemic stroke in males, females and both sexes combined (standardized coefficients = 0.515, 0.470 and 0.483, p < 0.001); similar associations were found for the prevalence of ischemic stroke (standardized coefficients = 0.471, 0.417 and 0.438, p < 0.001). The incidence and prevalence of ischemic stroke changed significantly at the global level and were independently associated with natural disasters. Both males and females show common but different vulnerabilities to natural disasters. This evidence supports policy making and resource allocation for disaster response and disease burden reduction.


Assuntos
Saúde Global/tendências , AVC Isquêmico/epidemiologia , Desastres Naturais , Feminino , Humanos , Incidência , AVC Isquêmico/diagnóstico , Masculino , Prevalência , Medição de Risco , Fatores de Risco , Distribuição por Sexo , Fatores Sexuais , Fatores de Tempo
12.
Nat Methods ; 19(2): 195-204, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35132244

RESUMO

Cryo-electron microscopy (cryo-EM) has become a leading approach for protein structure determination, but it remains challenging to accurately model atomic structures with cryo-EM density maps. We propose a hybrid method, CR-I-TASSER (cryo-EM iterative threading assembly refinement), which integrates deep neural-network learning with I-TASSER assembly simulations for automated cryo-EM structure determination. The method is benchmarked on 778 proteins with simulated and experimental density maps, where CR-I-TASSER constructs models with a correct fold (template modeling (TM) score >0.5) for 643 targets that is 64% higher than the best of some other de novo and refinement-based approaches on high-resolution data samples. Detailed data analyses showed that the main advantage of CR-I-TASSER lies in the deep learning-based Cα position prediction, which significantly improves the threading template quality and therefore boosts the accuracy of final models through optimized fragment assembly simulations. These results demonstrate a new avenue to determine cryo-EM protein structures with high accuracy and robustness covering various target types and density map resolutions.


Assuntos
Microscopia Crioeletrônica/métodos , Proteínas/química , Software , Biologia Computacional/métodos , Modelos Moleculares , Complexos Multiproteicos/química , Redes Neurais de Computação , Conformação Proteica
13.
Molecules ; 27(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35163951

RESUMO

Phosphorus in the form of phosphate (Pi) is an essential element for metabolic processes, including lipid metabolism. In yeast, the inositol polyphosphate kinase vip1 mediated synthesis of inositol heptakisphosphate (IP7) regulates the phosphate-responsive (PHO) signaling pathway, which plays an important role in response to Pi stress. The role of vip1 in Pi stress and lipid metabolism of Candida albicans has not yet been studied. We found that when vip1Δ/Δ was grown in glucose medium, if Pi was supplemented in the medium or mitochondrial Pi transporter was overexpressed in the strain, the lipid droplet (LD) content was reduced and membrane damage was alleviated. However, further studies showed that neither the addition of Pi nor the overexpression of the Pi transporter affected the energy balance of vip1Δ/Δ. In addition, the LD content of vip1Δ/Δ grown in Pi limitation medium PNMC was lower than that grown in SC, and the metabolic activity of vip1Δ/Δ grown in PNMC was also lower than that grown in SC medium. This suggests that the increase in Pi demand by a high energy metabolic rate is the cause of LD accumulation in vip1Δ/Δ. In addition, in the vip1Δ/Δ strains, the core transcription factor PHO4 in the PHO pathway was transported to the vacuole and degraded, which reduced the pathway activity. However, this does not mean that knocking out vip1 completely blocks the activation of the PHO pathway, because the LD content of vip1Δ/Δ grown in the medium with ß-glycerol phosphate as the Pi source was significantly reduced. In summary, the increased Pi demand and the decreased PHO pathway activity in vip1Δ/Δ ultimately lead to LD accumulation and cell membrane damage.


Assuntos
Metabolismo Energético/fisiologia , Fosfotransferases (Aceptor do Grupo Fosfato)/metabolismo , Candida albicans/metabolismo , Membrana Celular/metabolismo , Expressão Gênica/genética , Regulação Fúngica da Expressão Gênica/genética , Fosfatos de Inositol , Gotículas Lipídicas/metabolismo , Fosfatos/metabolismo , Fosforilação , Fosfotransferases (Aceptor do Grupo Fosfato)/fisiologia , Transdução de Sinais , Fatores de Transcrição/metabolismo , Vacúolos/metabolismo
14.
Brief Bioinform ; 23(2)2022 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-35152277

RESUMO

With the rapid progress of deep learning in cryo-electron microscopy and protein structure prediction, improving the accuracy of the protein structure model by using a density map and predicted contact/distance map through deep learning has become an urgent need for robust methods. Thus, designing an effective protein structure optimization strategy based on the density map and predicted contact/distance map is critical to improving the accuracy of structure refinement. In this article, a protein structure optimization method based on the density map and predicted contact/distance map by deep-learning technology was proposed in accordance with the result of matching between the density map and the initial model. Physics- and knowledge-based energy functions, integrated with Cryo-EM density map data and deep-learning data, were used to optimize the protein structure in the simulation. The dynamic confidence score was introduced to the iterative process for choosing whether it is a density map or a contact/distance map to dominate the movement in the simulation to improve the accuracy of refinement. The protocol was tested on a large set of 224 non-homologous membrane proteins and generated 214 structural models with correct folds, where 4.5% of structural models were generated from structural models with incorrect folds. Compared with other state-of-the-art methods, the major advantage of the proposed methods lies in the skills for using density map and contact/distance map in the simulation, as well as the new energy function in the re-assembly simulations. Overall, the results demonstrated that this strategy is a valuable approach and ready to use for atomic-level structure refinement using cryo-EM density map and predicted contact/distance map.


Assuntos
Aprendizado Profundo , Microscopia Crioeletrônica/métodos , Proteínas de Membrana , Modelos Moleculares , Conformação Proteica
15.
Environ Res ; 209: 112877, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35131324

RESUMO

BACKGROUND: Studies on the association of greenness with respiratory health are scarce in developing countries, and previous studies in China have focused on only one or two indicators of lung function. OBJECTIVE: The study aims to evaluate the associations of residential greenness with full-spectrum lung function indicators and prevalence of chronic obstructive pulmonary disease (COPD). METHODS: This nationwide cross-sectional survey included 50,991 participants from the China Pulmonary Health study. Lung function indicators included four categories: indicators of obstructive ventilatory dysfunction (FEV1, FVC and FEV1/FVC); an indicator of large-airway dysfunction (PEF); indicators of small-airway dysfunction (FEF25-75% and FEV3/FEV6); and other indicators. Residential greenness was assessed by the Normalized Difference Vegetation Index (NDVI). Multivariable linear regression models and logistic regression models were used to analyze associations of greenness with lung function and COPD prevalence. RESULTS: Within the 500 m buffer, an interquartile range (IQR) increase in NDVI was associated with higher FEV1 (24.76 mL), FVC (16.52 mL), FEV1/FVC (0.38), FEF50% (56.34 mL/s), FEF75% (33.43 mL/s), FEF25-75% (60.73 mL/s), FEV3 (18.59 mL), and FEV6 (21.85 mL). However, NDVI was associated with lower PEF. In addition, NDVI was significantly associated with 10% lower odds of COPD. The stratified analyses found that the associations were only significant in middle-young people, females, and nonsmokers. The associations were influenced by geographic regions. CONCLUSIONS: Residential greenness was associated with better lung function and lower odds of COPD in China. These findings provide a scientific basis for healthy community planning.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Adolescente , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Pulmão , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Testes de Função Respiratória
16.
Adv Mater ; 34(14): e2108847, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35102635

RESUMO

2D van der Waals (vdW) transition-metal oxyhalides with low symmetry, novel magnetism, and good stability provide a versatile platform for conducting fundamental research and developing spintronics. Antiferromagnetic FeOCl has attracted significant interest owing to its unique semiconductor properties and relatively high Néel temperature. Herein, good-quality centimeter-scale FeOCl single crystals are controllably synthesized using the universal temperature-oscillation chemical vapor transport (TO-CVT) method. The crystal structure, bandgap, and anisotropic behavior of the 2D FeOCl are explored in detail. The absorption spectrum and electrical measurements reveal that 2D FeOCl is a semiconductor with an optical bandgap of ≈2.1 eV and a resistivity of ≈10-1  Ω m at 295 K, and the bandgap increases with decreasing thickness. Strong in-plane optical and electrical anisotropies are observed in 2D FeOCl flakes, and the maximum resistance anisotropic ratio reaches 2.66 at 295 K. Additionally, the lattice vibration modes are studied through temperature-dependent Raman spectra and first-principles density functional calculations. A significant decrease in the Raman frequencies below the Néel temperature is observed, which results from the strong spin-phonon coupling effect in 2D FeOCl. This study provides a high-quality low-symmetry vdW magnetic candidate for miniaturized spintronics.

17.
Front Biosci (Landmark Ed) ; 27(1): 18, 2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-35090323

RESUMO

AIMS: Intrahepatic cholangiocarcinoma (ICC) is a highly malignant and heterogeneous cancer with a poor prognosis. At present, there is no optimal treatment except for surgical resection, and recurrence after resection will lead to death due to multidrug resistance. Changes in the redox signal have been found to be closely related to the growth and drug resistance of tumor cells. Therefore, the purpose of this study was to screen small molecule compounds from the redox library to find a drug for anti-ICC and to explore its downstream mechanism. MATERIAL AND METHODS: Tumor clone and sphere formation of ICC cell lines, as well as mouse ICC organoid proliferation assays were utilized to screen the candidate drug in the Redox library. Western blotting, quantitative reverse-transcription polymerase chain reaction (qRT-PCR), as well as cell apoptosis and cell cycle flow cytometry assays were used to explore the mechanism. RESULTS: We found that Hinokitiol was a candidate drug through inhibition of tumor clone and sphere formation, and the expression of cancer stem cell (CSC)-related genes. Furthermore, Hinokitiol significantly inhibited the proliferation of ICC cells by downregulating the ERK and P38 pathways. In addition, the combination of Hinokitiol and Palbociclib showed a significant inhibitory effect on human ICC cells and mouse ICC organoids. CONCLUSION: Hinokitiol may have the potential to be developed as a clinical therapeutic drug for ICC treatment.


Assuntos
Antineoplásicos , Neoplasias dos Ductos Biliares , Colangiocarcinoma , Animais , Antineoplásicos/uso terapêutico , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/metabolismo , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/genética , Colangiocarcinoma/metabolismo , Camundongos , Monoterpenos , Oxirredução , Tropolona/análogos & derivados
18.
Foods ; 11(2)2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35053925

RESUMO

Quinoa peptides are the bioactive components obtained from quinoa protein digestion, which have been proved to possess various biological activities. However, there are few studies on the anticancer activity of quinoa peptides, and the mechanism has not been clarified. In this study, the novel quinoa peptides were obtained from quinoa protein hydrolysate and identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The anticancer activity of these peptides was predicted by PeptideRanker and evaluated using an antiproliferative assay in colon cancer Caco-2 cells. Combined with the result of histone deacetylase 1 (HDAC1) inhibitory activity assay, the highly anticancer activity peptides FHPFPR, NWFPLPR, and HYNPYFPG were screened and further investigated. Molecular docking was used to analyze the binding site between peptides and HDAC1, and results showed that three peptides were bound in the active pocket of HDAC1. Moreover, real-time quantitative polymerase chain reaction (RT-qPCR), and Western blot showed that the expression of HDAC1, NFκB, IL-6, IL-8, Bcl-2 was significantly decreased, whereas caspase3 expression showed a remarkable evaluation. In conclusion, quinoa peptides may have the potential to protect against cancer development by inhibiting HDAC1 activity and regulating the expression of the cancer-related genes, which indicates that these peptides could be explored as functional foods to alleviate colon cancer.

19.
Elife ; 112022 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-35073255

RESUMO

Though being fundamental to global diversity distribution, little is known about the geographic pattern of soil microorganisms across different biotas on a large scale. Here, we investigated soil prokaryotic communities from Chinese northern grasslands on a scale up to 4000 km in both alpine and temperate biotas. Prokaryotic similarities increased over geographic distance after tipping points of 1760-1920 km, generating a significant U-shape pattern. Such pattern was likely due to decreased disparities in environmental heterogeneity over geographic distance when across biotas, supported by three lines of evidences: (1) prokaryotic similarities still decreased with the environmental distance, (2) environmental selection dominated prokaryotic assembly, and (3) short-term environmental heterogeneity followed the U-shape pattern spatially, especially attributed to dissolved nutrients. In sum, these results demonstrate that environmental selection overwhelmed the geographic 'distance' effect when across biotas, overturning the previously well-accepted geographic pattern for microbes on a large scale.


Assuntos
Pradaria , Células Procarióticas , Microbiologia do Solo , Biodiversidade , Biota , China , Ecossistema , Solo/química
20.
Nano Lett ; 22(3): 1242-1250, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35061398

RESUMO

Two-dimensional (2D) magnetic materials have attracted significant attention for promising applications in energy-saving logic and robust memory devices. However, most 2D magnets discovered so far typically feature drawbacks for practical applications due to low critical temperatures. Herein, we synthesize ultrathin room-temperature (RT) magnetic Fe7Se8 nanoflakes via the space-confined chemical vapor deposition method. It is found that the appropriate supply and control of Se concentration in the reaction chamber is crucial for synthesizing high-quality nonstoichiometric Fe7Se8 nanoflakes. Cryogenic electrical and magnetic characterizations reveal the emergence of spin reorientation at ∼130 K and the survival of long-range magnetic ordering up to room temperature. The RT magnetic domain structures with different thicknesses are also uncovered by magnetic force microscopy. Moreover, theoretical calculations confirm the spin configuration and metallic band structure. The outstanding characteristics exhibited by Fe7Se8 nanoflakes, including RT magnetism, spin reorientation property, and good electrical conductivity, make them a potential candidate for RT spintronics.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...