Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
1.
Phys Chem Chem Phys ; 26(1): 612-620, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38086641

RESUMO

Two-dimensional (2D) ß-TeO2 is a novel semiconductor with potential applications in electronic circuits due to its air-stability and ultra-high carrier mobility. In this study, we explore the possibility of using a 2D ß-TeO2 monolayer for the detection of gaseous pollutants including SO2, NO2, H2S, CO2, CO, and NH3 gas molecules based on first-principles calculations. The adsorption properties including the adsorption energy, adsorption distance and charge transfer indicate that the interaction between 2D ß-TeO2 and the six gases is via a physisorption mechanism. Among the six gas adsorption systems, the SO2 adsorption system has the most negative adsorption energy and the largest charge transfer. In addition, the adsorption of SO2 obviously changes the electrical conductivity of the ß-TeO2 monolayer because the band gap decreases from 2.727 eV to 1.897 eV after adsorbing SO2. Our results suggest that the 2D ß-TeO2 should be an eminently promising SO2 sensing material.

3.
Nature ; 537(7621): 508-514, 2016 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-27626380

RESUMO

Approximately one-third of all mammalian genes are essential for life. Phenotypes resulting from knockouts of these genes in mice have provided tremendous insight into gene function and congenital disorders. As part of the International Mouse Phenotyping Consortium effort to generate and phenotypically characterize 5,000 knockout mouse lines, here we identify 410 lethal genes during the production of the first 1,751 unique gene knockouts. Using a standardized phenotyping platform that incorporates high-resolution 3D imaging, we identify phenotypes at multiple time points for previously uncharacterized genes and additional phenotypes for genes with previously reported mutant phenotypes. Unexpectedly, our analysis reveals that incomplete penetrance and variable expressivity are common even on a defined genetic background. In addition, we show that human disease genes are enriched for essential genes, thus providing a dataset that facilitates the prioritization and validation of mutations identified in clinical sequencing efforts.


Assuntos
Embrião de Mamíferos/embriologia , Embrião de Mamíferos/metabolismo , Genes Essenciais/genética , Genes Letais/genética , Mutação/genética , Fenótipo , Animais , Sequência Conservada/genética , Doença , Estudo de Associação Genômica Ampla , Ensaios de Triagem em Larga Escala , Humanos , Imageamento Tridimensional , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Penetrância , Polimorfismo de Nucleotídeo Único/genética , Homologia de Sequência
4.
Chem Soc Rev ; 49(1): 263-285, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31825417

RESUMO

Since graphene has been successfully exfoliated, two-dimensional (2D) materials constitute a vibrant research field and open vast perspectives in high-performance applications. Among them, bismuthene and 2D bismuth (Bi) are unique with superior properties to fabricate state-of-the-art energy saving, storage and conversion devices. The largest experimentally determined bulk gap, even larger than those of stanene and antimonene, allows 2D Bi to be the most promising candidate to construct room-temperature topological insulators. Moreover, 2D Bi exhibits cyclability for high-performance sodium-ion batteries, and the enlarged surface together with the good electrochemical activity renders it an efficient electrocatalyst for energy conversion. Also, the air-stability of 2D Bi is better than that of silicene, germanene, phosphorene and arsenene, which could enable more practical applications. This review aims to thoroughly explore the fundamentals of 2D Bi and its improved fabrication methods, in order to further bridge gaps between theoretical predictions and experimental achievements in its energy-related applications. We begin with an introduction of the status of 2D Bi in the 2D-material family, which is followed by descriptions of its intrinsic properties along with various fabrication methods. The vast implications of 2D Bi for high-performance devices can be envisioned to add a new pillar in energy sciences. In addition, in the context of recent pioneering studies on moiré superlattices of other 2D materials, we hope that the improved manipulation techniques of bismuthene, along with its unique properties, might even enable 2D Bi to play an important role in future energy-related twistronics.

5.
Nano Lett ; 19(2): 1118-1123, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30681340

RESUMO

Bismuth has garnered tremendous interest for Na-ion batteries (NIBs) due to potentially high volumetric capacity. Yet, the bismuth upon sodiation/desodiation experiencing structure and phase transitions remains unclear, which sets a challenge for accessing nanotechnology and nanofabrication to achieve its applicability. Here, we use in situ transmission electron microscopy to disclose the structure and phase transitions of layered bismuth (few-layer bismuth nanosheets) during Na+ intercalation and alloying processes. Multistep phase transitions from Bi → NaBi → c-Na3Bi (cubic) → h-Na3Bi (hexagonal) are clearly identified, during which the Na+ migration from interlayer to in-plane evokes the structure transition from ABCABC stacking type of c-Na3Bi to ABABAB stacking type of h-Na3Bi. It is found that the metastable c-Na3Bi devotes to buffer the dramatic structure changes from thermodynamic stable h-Na3Bi, which unveils the origin of volume expansion for bismuth and has important consequences for 2D in-plane structure. As the lateral ductility can efficiently alleviate the in-plane mechanical strain caused by the Na+ migration, the few-layer bismuth nanosheet exhibits a potential cyclability for NIBs. Our findings will encourage more attention to bismuthene as a novel anode material for secondary batteries.

6.
Chem Soc Rev ; 47(3): 982-1021, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29210397

RESUMO

Phosphorene, an emerging two-dimensional material, has received considerable attention due to its layer-controlled direct bandgap, high carrier mobility, negative Poisson's ratio and unique in-plane anisotropy. As cousins of phosphorene, 2D group-VA arsenene, antimonene and bismuthene have also garnered tremendous interest due to their intriguing structures and fascinating electronic properties. 2D group-VA family members are opening up brand-new opportunities for their multifunctional applications encompassing electronics, optoelectronics, topological spintronics, thermoelectrics, sensors, Li- or Na-batteries. In this review, we extensively explore the latest theoretical and experimental progress made in the fundamental properties, fabrications and applications of 2D group-VA materials, and offer perspectives and challenges for the future of this emerging field.

7.
Am J Pathol ; 186(8): 2117-2128, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27418549

RESUMO

Duodenum-jejunum gastric bypass (DJB) has been used to treat morbid diabetic patients. However, neither the suitability among patients nor the mechanisms of this surgical treatment is clear. Previously, we reported a new mouse strain named Timo as type 2 diabetes model caused by brain-derived neurotrophic factor (Bdnf) deficiency. In this study, we found that DJB on Timo mice reversed their metabolic abnormalities without altering the expression of Bdnf. Glucose tolerance and insulin sensitivity were improved greatly, along with reduction of fat accumulation in liver and white adipose tissue. The gut flora population was altered by DJB with increased proportion of Firmicutes and decreased Actinobacteria and Proteobacteria in the ileum after surgery. Systemic inflammation in Timo mice was greatly suppressed with less macrophage infiltration and lower tumor necrosis factor-α levels in liver and white adipose tissue after surgery. Interestingly, the alteration of gut microflora abundance and improved metabolism preceded the inflammation alleviation after DJB surgery. These results suggested that DJB can reverse Bdnf deficiency-associated metabolic abnormality. In addition, the reduced inflammation may not be the initial cause for the DJB-associated metabolic and microbiota alterations. The increased BDNF protein levels in hypothalamus and hippocampus may result from microbiota change after DJB surgery.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/deficiência , Diabetes Mellitus Experimental/cirurgia , Diabetes Mellitus Tipo 2/cirurgia , Derivação Gástrica , Microbioma Gastrointestinal , Animais , Western Blotting , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Reação em Cadeia da Polimerase em Tempo Real
9.
Adv Sci (Weinh) ; 11(5): e2305567, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38059797

RESUMO

The optimization of charge transport with electron-hole separation directed toward specific redox reactions is a crucial mission for artificial photosynthesis. Bismuth vanadate (BiVO4 , BVO) is a popular photoanode material for solar water splitting, but it faces tricky challenges in poor charge separation due to its modest charge transport properties. Here, a concept of the external electron transport layer (ETL) is first proposed and demonstrated its effectiveness in suppressing the charge recombination both in bulk and at surface. Specifically, a conformal carbon capsulation applied on BVO enables a remarkable increase in the charge separation efficiency, thanks to its critical roles in passivating surface charge-trapping sites and building external conductance channels. Through decorated with an oxygen evolution catalyst to accelerate surface charge transfer, the carbon-encased BVO (BVO@C) photoanode manifests durable water splitting over 120 h with a high current density of 5.9 mA cm-2 at 1.23 V versus the reversible hydrogen electrode (RHE) under 1 sun irradiation (100 mW cm-2 , AM 1.5 G), which is an activity-stability trade-off record for single BVO light absorber. This work opens up a new avenue to steer charge separation via external ETL for solar fuel conversion.

10.
Int J Womens Health ; 16: 783-795, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38737496

RESUMO

Objective: This cross-sectional study aimed to explore the association of overweight and inflammatory indicators with breast cancer risk in Chinese patients. Methods: Weight, height, and peripheral blood inflammatory indicators, including white blood cell count (WBC), neutrophil count (NE), lymphocyte count (LY), platelet count (PLT) and the concentration of hypersensitivity C-reactive protein (hsCRP), were collected in 383 patients with benign breast lumps (non-cancer) and 358 patients with malignant breast tumors (cancer) at the First Affiliated Hospital of Soochow University, China, from March 2018 to July 2020. Body mass index (BMI), neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) and systemic immune-inflammation index (SII) were determined according to the ratio equation. The correlations among overweight, inflammatory indicators, and the proportion of non-cancer or cancer cases were analyzed. Results: BMI is associated with an increased breast cancer risk. Compared with non-cancer patients, the average WBC count, NE count, NLR, and level of hsCRP were significantly higher in cancer patients. The level of hsCRP was closely associated with the size of malignant breast tumors. Conclusion: We conclude that overweight and high levels of hsCRP may serve as putative risk factors for malignant breast tumors in Chinese women.

11.
J Gastrointestin Liver Dis ; 33(2): 269-277, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38944855

RESUMO

Colorectal cancer is a prevalent malignancy, with advanced and metastatic forms exhibiting poor treatment outcomes and high relapse rates. To enhance patient outcomes, a comprehensive understanding of the pathophysiological processes and the development of targeted therapies are imperative. The high heterogeneity of colorectal cancer demands precise and personalized treatment strategies. Colorectal cancer organoids, a three-dimensional in vitro model, have emerged as a valuable tool for replicating tumor biology and exhibit promise in scientific research, disease modeling, drug screening, and personalized medicine. In this review, we present an overview of colorectal cancer organoids and explore their applications in research and personalized medicine, while also discussing potential future developments in this field.


Assuntos
Neoplasias Colorretais , Organoides , Medicina de Precisão , Humanos , Organoides/patologia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Animais
12.
J Affect Disord ; 320: 247-253, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36195169

RESUMO

BACKGROUND: With the pandemic of COVID, the public are faced with tremendous threatens both physically and mentally. Postpartum depression (PPD) is one of the most serious complications of childbearing, bringing severe impact on a woman's mental state and mood after birth. Research has shown that maternal mental state is closely correlated with PPD, those undergo the emergency or significant life changes during the postpartum period are more likely to suffer from PPD. In this study, we conducted the meta-analysis to estimate the association between PPD and COVID-19 pandemic. METHODS: PubMed, Web of Science, PsycINFO, ScienceDirect, CNKI, China Science and Technology Journal Database, and WANFANG Database were searched for potentially relevant articles published before April 2022. Review Manager 5.2 was used to perform a meta-analysis and subgroup analysis to compute the pooled odds ratio. RESULTS: A total of 26 studies were included in this review. The overall pooled prevalence of PPD in the review was 24 % (95 % CI: 0.19-0.29), with China's at 22 % (95 % CI 0.16-0.28) and other countries at 25 % (95 % CI 0.18-0.32) during the COVID-19 pandemic. Moreover, compared to those who did not experience COVID-19, those who experienced it had an increased risk of PPD[OR:1.83(95 % CI 1.70-1.97)]. CONCLUSIONS: According to this analysis, there was a significantly higher prevalence and odds of PPD in those who suffered from the COVID-19 pandemic. Additionally, we also found that China had a lower prevalence of postpartum depression than other countries during the COVID-19 pandemic. Our study may provide the instruction for the care of new mother under the situation of COVID-19 prevalence.


Assuntos
COVID-19 , Depressão Pós-Parto , Humanos , Feminino , Depressão Pós-Parto/epidemiologia , Depressão Pós-Parto/etiologia , COVID-19/epidemiologia , Depressão/epidemiologia , Pandemias , Período Pós-Parto , Fatores de Risco
13.
Nat Commun ; 14(1): 2342, 2023 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-37095176

RESUMO

Triple-negative breast cancer (TNBC) is a subtype of breast cancer with poor outcome and lacks of approved targeted therapy. Overexpression of epidermal growth factor receptor (EGFR) is found in more than 50% TNBC and is suggested as a driving force in progression of TNBC; however, targeting EGFR using antibodies to prevent its dimerization and activation shows no significant benefits for TNBC patients. Here we report that EGFR monomer may activate signal transducer activator of transcription-3 (STAT3) in the absence of transmembrane protein TMEM25, whose expression is frequently decreased in human TNBC. Deficiency of TMEM25 allows EGFR monomer to phosphorylate STAT3 independent of ligand binding, and thus enhances basal STAT3 activation to promote TNBC progression in female mice. Moreover, supplying TMEM25 by adeno-associated virus strongly suppresses STAT3 activation and TNBC progression. Hence, our study reveals a role of monomeric-EGFR/STAT3 signaling pathway in TNBC progression and points out a potential targeted therapy for TNBC.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Animais , Camundongos , Neoplasias de Mama Triplo Negativas/metabolismo , Receptores ErbB/metabolismo , Transdução de Sinais/fisiologia , Linhagem Celular Tumoral , Fator de Transcrição STAT3/metabolismo , Proliferação de Células/fisiologia
14.
Bioact Mater ; 9: 554-565, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34820588

RESUMO

Nanoparticle-based chemophotothermal therapy (CPT) is a promising treatment for multidrug resistant tumors. In this study, a drug nanococktail of DIR825@histone was developed by employing doxorubicin (DOX), NIR dye IR825 and human histones for interventional nucleus-targeted CPT of multidrug resistant tumors with an interventional laser. After localized intervention, DIR825@histone penetrated tumor tissues by transcytosis, efficiently entered tumor cells and targeted the cell nuclei. DIR825@histone also exhibited good photothermal performance and thermal-triggered drug release. Efficient multidrug resistant tumor inhibition was achieved by enhanced CPT sensitization and MDR reversion via nuclear targeting. Moreover, an interventional laser assisted DIR825@histone in inhibiting multidrug resistant tumors by promoting the sufficient delivery of laser energy inside the tumor while reducing skin injury. Therefore, DIR825@histone together with this interventional nucleus-targeted CPT strategy holds great promise for treating multidrug resistant tumors.

15.
Front Pharmacol ; 13: 842131, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35242042

RESUMO

Bidens plants are annuals or perennials of Asteraceae and usually used as medicinal materials in China. They are difficult to identify by using traditional identification methods because they have similar morphologies and chemical components. Universal DNA barcodes also cannot identify Bidens species effectively. This situation seriously hinders the development of medicinal Bidens plants. Therefore, developing an accurate and effective method for identifying medicinal Bidens plants is urgently needed. The present study aims to use phylogenomic approaches based on organelle genomes to address the confusing relationships of medicinal Bidens plants. Illumina sequencing was used to sequence 12 chloroplast and eight mitochondrial genomes of five species and one variety of Bidens. The complete organelle genomes were assembled, annotated and analysed. Phylogenetic trees were constructed on the basis of the organelle genomes and highly variable regions. The organelle genomes of these Bidens species had a conserved gene content and codon usage. The 12 chloroplast genomes of the Bidens species were 150,489 bp to 151,635 bp in length. The lengths of the eight mitochondrial genomes varied from each other. Bioinformatics analysis revealed the presence of 50-71 simple sequence repeats and 46-181 long repeats in the organelle genomes. By combining the results of mVISTA and nucleotide diversity analyses, seven candidate highly variable regions in the chloroplast genomes were screened for species identification and relationship studies. Comparison with the complete mitochondrial genomes and common protein-coding genes shared by each organelle genome revealed that the complete chloroplast genomes had the highest discriminatory power for Bidens species and thus could be used as a super barcode to authenticate Bidens species accurately. In addition, the screened highly variable region trnS-GGA-rps4 could be also used as a potential specific barcode to identify Bidens species.

16.
Adv Mater ; 34(13): e2108541, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35040212

RESUMO

Aqueous lithium-ion batteries (ALIBs) with nonflammable feature attract great attention for large-scale energy storage. However, the layered cathode materials (such as LiCoO2 ) present serious capacity decay in ALIBs. The degradation mechanism of layered cathode materials in ALIBs is still not clear and an effective strategy to improve cycling stability remains a great challenge. In this work, the authors use LiCoO2 as a typical example to investigate its structural degradation in aqueous electrolytes. It is found that H+ insertion accelerated irreversible layered-to-spinel phase transition is the main reason causing structural degradation and fast capacity fading in LiCoO2 . Subsequently, Li-excess Li1+ t Co1- t O2- t with intermediate spin Co3+ is developed to mitigate H+ influence and the adverse phase transition in aqueous electrolyte. It is interesting to discover that reversible water intercalation/deintercalation occurs in the layered structure during charge/discharge, which effectively suppresses the layered-to-spinel phase transition with cycling. Benefiting from the stabilized layered structure, the Li-excess Li1.08 Co0.92 O1.92 shows a significantly improved cycling performance in the neutral aqueous electrolyte with a large specific capacity and excellent rate capability. This work provides a promising structural regulation strategy for the layered cathode materials, enabling their potential application in ALIBs.

17.
ACS Omega ; 7(9): 7825-7836, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35284738

RESUMO

Wang-Bi capsule (WB) is a traditional Chinese medicine (TCM)-based herbal formula, and it has been used in the treatment of rheumatoid arthritis (RA) in China for many years. Additionally, WB is also used as a supplement to the treatment of osteoarthritis (OA) in clinical practice. Our research aimed to reveal the therapeutic effects and underling mechanism of WB on RA and OA through computational system pharmacology analysis and experimental study. Based on network pharmacology analysis, a total of 173 bioactive compounds interacted with 417 common gene targets related to WB, RA, and OA, which mainly involved the PI3K-Akt signaling pathway. In addition, the serine-threonine protein kinase 1 (AKT1) might be a core gene protein for the action of WB, which was further emphasized by molecular docking. Moreover, the anti-inflammatory activity of WB in vitro was confirmed by reducing NO production in lipopolysaccharide (LPS)-induced RAW264.7 cells. The anti-RA and OA effects of WB in vivo were confirmed by ameliorating the disease symptoms of collagen II-induced RA (CIA) and monosodium iodoacetate-induced OA (MIA) in rats, respectively. Furthermore, the role of the PI3K-Akt pathway in the action of WB was preliminarily verified by western blot analysis. In conclusion, our study elucidated that WB is a potentially effective strategy for the treatment of RA and OA, which might be achieved by regulating the PI3K-Akt pathway. It provides us with systematic insights into the effects and mechanism of WB on RA and OA.

18.
Medicine (Baltimore) ; 100(19): e25858, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34106631

RESUMO

RATIONALE: Acquired cystic disease-associated renal cell carcinoma (ACKD-RCC) is a unique subtype of renal cell carcinoma (RCC) and is found exclusively in patients with end-stage renal disease. We report a case of intracapsular nephrectomy (ICAN) of renal allograft with ACKD-RCC. To our knowledge, this is the first case in Asia of ICAN of renal allograft to treat ACKD-RCC. PATIENT CONCERNS: A 51-year-old male patient with a history of allogeneic kidney transplantation (23 years previously) presented with renal cystic degeneration of the transplanted kidney over the past 2 years. DIAGNOSES: ICAN was used to remove the cystic kidney. INTERVENTIONS: The pathology report indicated clear cell renal cell carcinoma. OUTCOMES: Two years after surgery, computed tomography showed no tumor recurrence, and the patient's creatinine level was 3.5 mg/dl under hemodialysis. LESSONS: Removal of transplanted kidney with ACKD-RCC using ICAN is feasible to provide a mid-term tumor-free survival for the patient. Therefore, we consider nephrectomy as an early treatment for the nonfunctional cystic allograft kidney, in order to reduce the dosage of anti-rejection drugs, avoid the occurrence of transplanted kidney tumor, and provide the possibility for the patient an opportunity to receive a second kidney transplantation.


Assuntos
Carcinoma de Células Renais/cirurgia , Neoplasias Renais/cirurgia , Nefrectomia/métodos , Humanos , Doenças Renais Císticas/patologia , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Transplante Homólogo
19.
RSC Adv ; 11(6): 3363-3370, 2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35424317

RESUMO

In this paper, experimental and theoretical studies of the piezoelectric effect of two-dimensional ZnO nanostructures, including straight nanosheets (SNSs) and curved nanosheets (CNSs) are conducted. The results show that the CNSs have a great advantage in piezoelectric property over the SNSs; the maximum output current of the NG based on CNSs was measured to be about 260 nA, much higher than that generated by SNSs. For comparatively analyzing the working mechanics of both NGs, the piezopotential distribution of both CNS and SNS structures was studied using the finite element method. The simulation result that the piezopotential generated by CNSs is always much larger than that generated by SNSs in the case of lateral bending, has more advantages for piezoelectric NGs than the SNSs. This work may provide guidance for structural optimization of piezoelectric nanogenerators and designing high-performance self-powered strain sensors.

20.
ACS Appl Mater Interfaces ; 13(34): 40618-40628, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34416111

RESUMO

Nitrogen reduction reaction (NRR), as a green and sustainable technology, is far from a practical application due to the lack of efficient electrocatalysts. In this work, we found that antimonene, a group-VA elemental two-dimensional (2D) material, is attractive as an electrocatalyst for NRR. The antimonene here is acquired through chemical exfoliation of antimony (Sb) using H2SO4 for the first time, which simultaneously achieved efficient large-sized exfoliation and created a high density of active edge sites. Moreover, the concentration of defects shows a gradual increasing tendency as the treatment time extends. The obtained antimonene exhibited favorable average ammonia (NH3) yield and Faradaic efficiency as high as 2.08 µg h-1 cm-2 and 14.25% at -0.7 V versus RHE, respectively. Density functional theory calculations prove that the sufficient exposure of edge defects is favorable for reducing the reaction barrier and strengthening the interaction between antimonene and the intermediates of NRR, thus increasing the selectivity and yield rate of NH3. The chemical exfoliation of Sb reported here offers an alternative avenue to engineer the surface structures of group-VA elemental-based catalysts. Investigation of NRR using 2D antimonene can further provide deep insight into the mechanism and principle of NRR over group-VA elemental nanosheets.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA