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1.
Aging (Albany NY) ; 13(13): 17516-17535, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34233293

RESUMO

INTRODUCTION: Owing to the poor prognosis of Ewing's sarcoma, reliable prognostic biomarkers are highly warranted for clinical diagnosis of the disease. MATERIALS AND METHODS: A combination of the weighted correlation network analysis and differentially expression analysis was used for initial screening; glycolysis-related genes were extracted and subjected to univariate Cox, LASSO regression, and multivariate Cox analyses to construct prognostic models. The immune cell composition of each sample was analysed using CIBERSORT software. Immunohistochemical analysis was performed for assessing the differential expression of modelled genes in Ewing's sarcoma and paraneoplastic tissues. RESULTS: A logistic regression model constructed for the prognosis of Ewing's sarcoma exhibited that the patient survival rate in the high-risk group is much lower than in the low-risk group. CIBERSORT analysis exhibited a strong correlation of Ewing's sarcoma with naïve B cells, CD8+ T cells, activated NK cells, and M0 macrophages (P < 0.05). Immunohistochemical analysis confirmed the study findings. CONCLUSIONS: GLCE and TPI1 can be used as prognostic biomarkers to predict the prognosis of Ewing's sarcoma, and a close association of Ewing's sarcoma with naïve B cells, CD8+ T cells, activated NK cells, and M0 macrophages provides a novel approach to the disease immunotherapy.

2.
BMC Cancer ; 21(1): 838, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34284752

RESUMO

PURPOSE: Tumor bed (TB) delineation based on preoperative magnetic resonance imaging (pre-MRI) fused with postoperative computed tomography (post-CT) were compared to post-CT only to define pre-MRI may aid in improving the accuracy of delineation. METHODS AND MATERIALS: The pre-MRI imaging of 10 patients underwent radiotherapy (RT) after breast conserving surgery (BCS) were reviewed. Post-CT scans were acquired in the same prone position as pre-MRI. Pre-MRI and post-CT automatically match and then manual alignment was given to enhance fusion consistency. Three radiation oncologists and 2 radiologists delineated the clinical target volume (CTV) for CT-based. The gross target volume (GTV) of pre-MRI-based was determined by the volume of tumor acquired with 6 sequences: T1, T2, T2W-SPAIR, DWI, dyn-eTHRIVE and sdyn-eTHRIVE, expended 10 mm to form the CTV-pre-MRI. Planning target volume (PTV) for each sequence was determined by CTV extended 15 mm, trimmed to 3 mm from skin and the breast-chest wall interface. The variability of the TB delineation were developed as follows: the mean volume, conformity index (CI) and dice coefficient (DC). RESULTS: The mean volumes of CTV and PTV delineated with CT were all larger than those with pre-MRI. The lower inter-observer variability was observed from PTV, especially in sdyn-eTHRIVE in all sequences. For each sequence of pre-MRI, all DCs were larger than post-CT, and the largest DC was observed by sdyn-eTHRIVE sequence fusion to post-CT. The overlap for PTV was significantly improved in the pre-MRI-based compared with the CT-based. CONCLUSIONS: TB volumes based on pre-MRI were smaller than post-CT with CVS increased. Pre-MRI provided a more precise definition of the TB with observers performed a smaller inter-observer variability than CT. Pre-MRI, especially in sdyn-eTHRIVE sequence, should help in reducing treatment volumes with the improved accuracy of TB delineation of adjuvant RT of breast cancer.

3.
Chem Commun (Camb) ; 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34254605

RESUMO

A novel activity-based Cu2+ fluorescent probe featuring multidentate binding sites was synthesized. It functions through chelation with Cu2+, which in turn specifically triggers hydrolysis of the probe to release a near-infrared emission with AIE + ESIPT properties. The probe was found to be capable of ratiometric imaging of Cu2+ in living HeLa cells.

4.
J Hazard Mater ; 419: 126506, 2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34218188

RESUMO

Nanoplastics are an emerging topic and have attracted increasing attention due to their widespread existence and potential toxicity on living organisms. The challenges of analytical methods for nanoplastics hinder the deeper understanding of toxicological effects and risk assessment of nanoplastics. In this work, a custom-built electromagnetic heating pyrolyzer was coupled to mass spectrometry for the rapid analysis of nanoplastics. Nanoplastics/microplastics were collected on the heat-resisting filter papers, then directly decomposed into gaseous products in the pyrolyzer and analyzed by mass spectrometry. The polystyrene nanoparticles were used to verify the performance of mass-traced quantification, and recoveries of 106-121% and precision of 9% were obtained. As a proof-of-principle experiment, the saline solution packed by polypropylene infusion bottles was aged for simulating indoor sunlight storage, where nanoplastics/microplastics were analyzed. The abundance models of nanoplastics/microplastics in the saline infusion bottle with aging time were assessed from both quality and quantity, for the first time. Results showed that nanoplastics/microplastics in medical infusion products could be generated under indoor sunlight exposure, which needs more attention due to the potential health risks. The proposed electromagnetic heating pyrolysis-mass spectrometry could be a promising method for assessing nanoplastics/microplastics.

5.
Artigo em Inglês | MEDLINE | ID: mdl-34202887

RESUMO

Redox-active humic acids (HA) are ubiquitous in terrestrial and aquatic systems and are involved in numerous electron transfer reactions affecting biogeochemical processes and fates of pollutants in soil environments. Redox-active contaminants are trapped in soil micropores (<2 nm) that have limited access to microbes and HA. Therefore, the contaminants whose molecular structure and properties are not damaged accumulate in the soil micropores and become potential pollution sources. Electron transfer capacities (ETC) of HA reflecting redox activities of low molecular weight fraction (LMWF, <2.5) HA can be detected by an electrochemical method, which is related to redox potentials (Eh) in soil and aquatic environments. Nevertheless, electron accepting capacities (EAC) and electron donating capacities (EDC) of these LMWF HA at different Eh are still unknown. EDC and EAC of different molecular weight HA at different Eh were analyzed using electrochemical methods. EAC of LMWF at -0.59 V was 12 times higher than that at -0.49 V, while EAC increased to 2.6 times when the Eh decreased from -0.59 V to -0.69 V. Afterward, LMWF can act as a shuttle to stimulate microbial Fe(III) reduction processes in microbial reduction experiments. Additionally, EAC by electrochemical analysis at a range of -0.49--0.59 V was comparable to total calculated ETC of different molecular weight fractions of HA by microbial reduction. Therefore, it is indicated that redox-active functional groups that can be reduced at Eh range of -0.49--0.59 are available to microbial reduction. This finding contributes to a novel perspective in the protection and remediation of the groundwater environment in the biogeochemistry process.

6.
Transl Oncol ; 14(10): 101177, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34271256

RESUMO

Although chemotherapy is an important treatment for advanced prostate cancer, its efficacy is relatively limited. Ultrasound-induced cavitation plays an important role in drug delivery and gene transfection. However, whether cavitation can improve the efficacy of chemotherapy for prostate cancer remains unclear. In this study, we treated RM-1 mouse prostate carcinoma cells with a combination of ultrasound-mediated microbubble cavitation and paclitaxel. Our results showed that combination therapy led to a more pronounced inhibition of cell viability and increased cell apoptosis. The enhanced efficacy of chemotherapy was attributed to the increased cell permeability induced by cavitation. Importantly, compared with chemotherapy alone (nab-paclitaxel), chemotherapy combined with ultrasound-mediated microbubble cavitation significantly inhibited tumor growth and prolonged the survival of tumor-bearing mice in an orthotopic mouse model of RM-1 prostate carcinoma, indicating the synergistic effects of combined therapy on tumor reduction. Furthermore, we analyzed tumor-infiltrating lymphocytes and found that during chemotherapy, the proportions of CTLA4+ cells and PD-1+/CTLA4+ cells in CD8+ T cells slightly increased after cavitation treatment.

7.
Huan Jing Ke Xue ; 42(7): 3136-3146, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212639

RESUMO

The spread of atmospheric pollutants in the Sichuan Basin is difficult because of its unique topography, static wind, high humidity, and other meteorological conditions. Owing to the acceleration of urbanization and industrialization, PM2.5 pollution in the region is becoming increasingly severe, and the Sichuan Basin has become one of the key areas of national air pollution prevention and control. In this study, based on the remote sensing inversion product of PM2.5 concentration, spatial autocorrelation and gray correlation analyses are used to evaluate the spatial and temporal distribution characteristics and influencing factors of PM2.5 concentration in the Sichuan Basin. The results show that PM2.5 concentration has significant spatial aggregation; the high-high aggregation types are concentrated, low-low aggregation types are more dispersed, and coniferous forest has a significantly higher inhibitory effect on the absorption of PM2.5 than the shrub, grassland, and other vegetation types. The main meteorological factors affecting PM2.5 concentration in the Sichuan Basin are wind speed and temperature; population density and economic scale are the main human-activity factors affecting PM2.5 concentration in the Sichuan Basin, and the change in the industrial structure and scale also has a certain influence on the PM2.5 concentration.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Monitoramento Ambiental , Análise Fatorial , Humanos , Material Particulado/análise , Estações do Ano
8.
Clin Respir J ; 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34260815

RESUMO

OBJECTIVE: This study aimed to evaluate the clinical role of C-X-C motif chemokine ligand (CXCL) family members in idiopathic pulmonary arterial hypertension (IPAH) patients. METHODS: CXCL1, CXCL8, CXCL10 and CXCL12 expressions in the serum samples of IPAH patients (N=39) and age/gender-matched controls (N=40) were detected by enzyme-linked immunosorbent assay. In IPAH patients, clinical features were collected and survival information was documented. RESULTS: CXCL1 (P<0.001), CXCL8 (P=0.001), CXCL10 (P<0.001) and CXCL12 (P<0.001) were increased in IPAH patients compared with controls, and receiver's operating characteristic curves showed that their combination was highly correlated with IPAH risk (area under curve: 0.881, 95% confidence interval: 0.805-0.958). Meanwhile, CXCL1 was positively correlated with mean pulmonary artery pressure (mPAP) (P=0.029) and high sensitive C-reactive protein (HsCRP) (P=0.015); CXCL8 was positively correlated with mPAP (P=0.044) and HsCRP (P=0.018) but negatively correlated with 6-minute walk test (6MWT) distance (P=0.029); CXCL10 was positively correlated with mean right artery pressure (P=0.002); and CXCL12 was positively correlated with World Health Organization functional class (P=0.047), mPAP (P=0.009), pulmonary vascular resistance (P=0.004), HsCRP (P=0.003) but negatively correlated with 6MWT distance (P=0.003) in IPAH patients. Moreover, CXCL12 was negatively correlated with overall survival (OS) (P=0.025), while CXCL1, CXCL8 and CXCL10 only showed minor tendencies to be negatively correlated with OS in IPAH patients without statistical significance (all P>0.05). CONCLUSION: CXCL1, CXCL8, CXCL10 and CXCL12 associate with increased IPAH risk, unfavorable clinical features; besides, CXCL12 correlates with worse OS in IPAH patients.

9.
Biosensors (Basel) ; 11(6)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198490

RESUMO

Tilted fiber Bragg grating, which has the advantages of both fiber Bragg grating and long-period fiber grating, has been widely studied for sensing in many fields, especially in the field of biochemistry. Calmodulin, which has a wide distribution in eukaryotes, can regulate several enzymes such as adenylate cyclase and guanylate cyclase and mediates several cellular processes such as cell proliferation and cyclic nucleotide metabolism. The abnormal levels of calmodulin in the body will result in serious effects from metabolism to nerve growth and memory. Therefore, it is important to measure the calmodulin concentration in the body. In this work, we propose and experimentally demonstrate a plasmonic tilted fiber Bragg grating-based biosensor for calmodulin detection. The biosensor was made using an 18° tilted fiber Bragg grating with a 50 nm-thick gold nanofilm coating the surface of the fiber, and transient receptor potential channels were bonded onto the surface of the gold nanofilm to serve as bio-detectors for calmodulin detection. Experimental results showed that the limit of detection using our biosensor was 0.44 nM. Furthermore, we also demonstrated that the interaction between calmodulin and transient receptor potential channels was quite weak without calcium in the solution, which agrees with the biology. Our proposed biosensor has a simple structure, is easy to manufacture, and is of small size, making it a good choice for real-time, label-free, and microliter-volume biomolecule detection.


Assuntos
Técnicas Biossensoriais , Calmodulina/análise , Desenho de Equipamento , Tecnologia de Fibra Óptica , Ouro , Fibras Ópticas , Refratometria , Ressonância de Plasmônio de Superfície
10.
Clin Chim Acta ; 521: 19-24, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34153276

RESUMO

Atherosclerosis, as a chronic inflammatory disease within the arterial wall, is a leading cause of morbidity and mortality worldwide due to its role in myocardial infarction, stroke and peripheral artery disease. Additional evidence is emerging that the angiopoietin-like (ANGPTL) family of proteins participate in the pathology of this disease process via endothelial dysfunction, inflammation, dyslipidemia, calcification, foam cell formation and platelet activation. This review summarizes current knowledge on the ANGPTL family of proteins in atherosclerosis related pathological processes. Moreover, the potential value of ANGPTL family proteins as predictive biomarkers in atherosclerosis is discussed. Given the attractive role of ANGPTL3, ANGPTL4, ANGPTL8 in atherosclerotic dyslipidemia via regulation of lipoprotein lipase (LPL), antisense oligonucleotide or/and monoclonal antibody-based inactivation of these proteins represent potential atherosclerotic therapies.

11.
Trials ; 22(1): 405, 2021 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-34147107

RESUMO

BACKGROUND: More than 50% cognitive impairment was reported by cancer patients before and after medical treatment. However, there are no effective interventions to manage the cognitive problem in women with breast cancer. This pilot study was designed to evaluate the protective effect of Baduanjin exercise on cognitive function and cancer-related symptoms in women with early-stage breast cancer undergoing chemotherapy. METHOD: A single-blinded, randomized control trial was designed. The trial will recruit 70 patients with early-stage breast cancer scheduled to receive chemotherapy from Shanghai in China. All participants will be randomly assigned to (1:1) the supervised Baduanjin group (5 times/week, 30 min each time) or the wait-list control group for 3 months. The effect of Baduanjin exercise intervention will be evaluated by outcome measures including subjective and objective cognitive function, symptoms (fatigue, depression, and anxiety), and health-related quality of life at pre-intervention (T0), 8 weeks (T1), and 12 weeks (T2). The PCI score in the FACT-Cog as the primary cognitive outcome will be reported descriptively, while effect sizes and 95% confidence intervals (CIs) will be calculated. The collected data will be analyzed by using an intention-to-treat principle and linear mixed-effects modeling. DISCUSSION: This is the first randomized clinical trial to investigate whether Baduanjin exercise will have a positive role in improving cognitive function in women with breast cancer receiving chemotherapy. If possible, Baduanjin exercise will be a potential non-pharmacological intervention to manage cognitive dysfunction and promote survivorship care among breast cancer survivors. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR) ChiCTR2000033152 . Registered on 22 May 2020.


Assuntos
Neoplasias da Mama , Intervenção Coronária Percutânea , Neoplasias da Mama/tratamento farmacológico , China , Cognição , Terapia por Exercício , Feminino , Humanos , Projetos Piloto , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Medicine (Baltimore) ; 100(22): e26219, 2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34087900

RESUMO

BACKGROUND: Autophagy is closely related to skin cutaneous melanoma (SKCM), but the mechanism involved is unclear. Therefore, exploration of the role of autophagy-related genes (ARGs) in SKCM is necessary. MATERIALS AND METHODS: Differential expression autophagy-related genes (DEARGs) were first analysed. Univariate and multivariate Cox regression analyses were used to evaluate the expression of DEARGs and prognosis of SKCM. Further, the expression levels of prognosis-related DEARGs were verified by immunohistochemical (IHC) staining. Finally, gene set enrichment analysis (GSEA) was used to explore the underlying molecular mechanisms of SKCM. RESULTS: Five ARGs (APOL1, BIRC5, EGFR, TP63, and SPNS1) were positively correlated with the prognosis of SKCM. IHC verified the results of the differential expression of these 5 ARGs in the bioinformatics analysis. According to the receiver operating characteristic curve, the signature had a good performance at predicting overall survival in SKCM. The signature could classify SKCM patients into high-risk or low-risk groups according to distinct overall survival. The nomogram confirmed that the risk score has a particularly large impact on the prognosis of SKCM. Calibration plot displayed excellent agreement between nomogram predictions and actual observations. Principal component analysis indicated that patients in the high-risk group could be distinguished from those in low-risk group. Results of GSEA indicated that the low-risk group is enriched with aggressiveness-related pathways such as phosphatidylinositol-3-kinase/protein kinase B and mitogen-activated protein kinase signalling pathways. CONCLUSION: Our study identified a 5-gene signature. It revealed the mechanisms of autophagy that lead to the progression of SKCM and established a prognostic nomogram that can predict overall survival of patients with SKCM. The findings of this study provide novel insights into the relationship between ARGs and prognosis of SKCM.


Assuntos
Autofagia/genética , Biologia Computacional/métodos , Melanoma/genética , Neoplasias Cutâneas/patologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Apolipoproteína L1/genética , Receptores ErbB/genética , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Melanoma/mortalidade , Proteínas de Membrana/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Nomogramas , Fosfatidilinositol 3-Quinase/metabolismo , Prognóstico , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Curva ROC , Fatores de Risco , Survivina/genética , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética
13.
Front Med ; 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34181195

RESUMO

We aimed to evaluate the effectiveness and safety of single-course initial regimens in patients with low-risk gestational trophoblastic neoplasia (GTN). In this trial (NCT01823315), 276 patients were analyzed. Patients were allocated to three initiated regimens: single-course methotrexate (MTX), single-course MTX + dactinomycin (ACTD), and multi-course MTX (control arm). The primary endpoint was the complete remission (CR) rate by initial drug(s). The primary CR rate was 64.4% with multi-course MTX in the control arm. For the single-course MTX arm, the CR rate was 35.8% by one course; it increased to 59.3% after subsequent multi-course MTX, with non-inferiority to the control (difference -5.1%,95% confidence interval (CI) -19.4% to 9.2%, P = 0.014). After further treatment with multi-course ACTD, the CR rate (93.3%) was similar to that of the control (95.2%, P = 0.577). For the single-course MTX + ACTD arm, the CR rate was 46.7% by one course, which increased to 89.1% after subsequent multi-course, with non-inferiority (difference 24.7%, 95% CI 12.8%-36.6%, P < 0.001) to the control. It was similar to the CR rate by MTX and further ACTD in the control arm (89.1% vs. 95.2%, P =0.135). Four patients experienced recurrence, with no death, during the 2-year follow-up. We demonstrated that chemotherapy initiation with single-course MTX may be an alternative regimen for patients with low-risk GTN.

14.
Medicine (Baltimore) ; 100(24): e25937, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34128842

RESUMO

ABSTRACT: The aim of this study was to investigate the correlation between single-nucleotide polymorphisms (SNPs) in the 3 primer of untranslated region (3'UTR) of the Pentraxin 3 (PTX3) gene and the risk of essential hypertension (EHT).PTX3 genotypes, rs2614, rs111451363, and rs73158510 locus, were found in 260 patients with EHT and 260 healthy controls. Quantitative real-time polymerase chain reaction was used to detect plasma hsa-miR-4766-5p levels. Enzyme-linked immunosorbent assay was used to detect plasma PTX3 levels. The dual-luciferase reporter assay was used to identify the binding site of hsa-miR-4766-5p to the PTX3.PTX3 rs2614 locus T allele was a high risk factor for EHT (odds ratio [OR] = 2.76, 95% confidence interval [CI]: 1.86-4.09, P < .01). Sex and diabetes history affected the correlation between PTX3 gene rs2614 locus SNP and EHT risk. The CCG haplotype was a protective factor for EHT (OR = 0.40, 95% CI: 0.28-0.57, P < .01), whereas the TCG haplotype was a risk factor for EHT (OR = 2.35, 95% CI: 1.51-3.66, P < .01). The plasma PTX3 level of patients with EHT was significantly higher than that of the control group, and the difference was statistically significant (P < .01). The area under the curve for EHT diagnosis in plasma PTX3 levels was 0.62 (95% CI: 0.57-0.66, P < .01). The plasma hsa-miR-4766-5p level in patients with EHT was significantly lower than that in the control group (P < .01). The area under the curve for the diagnosis of EHT according to the plasma hsa-miR-4766-5p level was 0.88 (95% CI: 0.85-0.91, P < .01). Plasma PTX3 levels were significantly negatively correlated with hsa-miR-4766-5p levels in patients with EHT and the control group (r = -0.87, -0.85, P < .01, P < .01). The PTX3 gene rs2614 locus C allele was the target gene of hsa-miR-4766-5p.The PTX3 rs2614 locus SNP is significantly associated with EHT risk.


Assuntos
Regiões 3' não Traduzidas/genética , Proteína C-Reativa/genética , Hipertensão Essencial/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Componente Amiloide P Sérico/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Área Sob a Curva , Sítios de Ligação , Estudos de Casos e Controles , Feminino , Genótipo , Haplótipos , Humanos , Masculino , MicroRNAs/sangue , Pessoa de Meia-Idade , Fatores de Risco
15.
PLoS One ; 16(6): e0252875, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34129634

RESUMO

OBJECTIVE: This study is aimed to develop a new nomogram for the clinical diagnosis of osteoarticular tuberculosis (TB). METHODS: xCell score estimation to obtained the immune cell type abundance scores. We downloaded the expression profile of GSE83456 from GEO and proceed xCell score estimation. The routine blood examinations of 326 patients were collected for further validation. We analyzed univariate and multivariate logistic regression to identified independent predicted factor for developing the nomogram. The performance of the nomogram was assessed using the receiver operating characteristic (ROC) curves. The correlation of ESR with lymphocytes, monocytes, and ML ratio was performed and visualized in osteoarticular TB patients. RESULTS: Compared with the healthy control group in the dataset GSE83456, the xCell score of basophils, monocytes, neutrophils, and platelets was higher, while lymphoid was lower in the EPTB group. The clinical data showed that the cell count of monocytes were much higher, while the cell counts of lymphocytes were lower in the osteoarticular TB group. AUCs of the nomogram was 0.798 for the dataset GSE83456, and 0.737 for the clinical data. We identified the ML ratio, BMI, and ESR as the independent predictive factors for osteoarticular TB diagnosis and constructed a nomogram for the clinical diagnosis of osteoarticular TB. AUCs of this nomogram was 0.843. CONCLUSIONS: We demonstrated a significant change between the ML ratio of the EPTB and non-TB patients. Moreover, we constructed a nomogram for the clinical diagnosis of the osteoarticular TB diagnosis, which works satisfactorily.

16.
Nat Nanotechnol ; 2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140672

RESUMO

The theoretical Shockley-Queisser limit of photon-electricity conversion in a conventional p-n junction could be potentially overcome by the bulk photovoltaic effect that uniquely occurs in non-centrosymmetric materials. Using strain-gradient engineering, the flexo-photovoltaic effect, that is, the strain-gradient-induced bulk photovoltaic effect, can be activated in centrosymmetric semiconductors, considerably expanding material choices for future sensing and energy applications. Here we report an experimental demonstration of the flexo-photovoltaic effect in an archetypal two-dimensional material, MoS2, by using a strain-gradient engineering approach based on the structural inhomogeneity and phase transition of a hybrid system consisting of MoS2 and VO2. The experimental bulk photovoltaic coefficient in MoS2 is orders of magnitude higher than that in most non-centrosymmetric materials. Our findings unveil the fundamental relation between the flexo-photovoltaic effect and a strain gradient in low-dimensional materials, which could potentially inspire the exploration of new optoelectronic phenomena in strain-gradient-engineered materials.

17.
Artigo em Inglês | MEDLINE | ID: mdl-34142346

RESUMO

BACKGROUND: For patients taking factor Xa (FXa) inhibitors who have life-threatening bleeding, emergency surgery, drug interactions, etc., a rapid and precise assay is needed to monitor for potential medication failure, to assess safety during periprocedural anticoagulation management, and to manage the care of chronically anticoagulated patients. Anti-factor Xa (anti-Xa) activity assays have been recommended in guidelines, but the evaluation of different calibrations of anti-Xa activity assays and the data on the recommended range are still limited, especially in the Asian population. METHODS: This is a nationwide multicenter methodology exploratory study in an Asian population, including nine hospitals from Beijing, Shanghai, Liaoning, Shandong, Jiangsu, Anhui, Henan, Chongqing, and Fujian. A total of 485 healthy volunteers and 219 patients taking rivaroxaban or apixaban (single dose) were enrolled in the study. High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS) was employed to detect plasma rivaroxaban and apixaban. The prothrombin time (PT), activated partial thromboplastin time (APTT), and levels of anti-Xa activity were tested as pharmacodynamic parameters in plasma samples. We evaluated the correlation of anti-Xa activity and blood concentration via HPLC-MS, and then compared the two methods of target drug-calibrated and low-molecular-weight heparin (LMWH)-antithrombin-calibrated anti-Xa activity. Correlations between variables were examined using Pearson's correlation analysis. Logistic regression was applied to evaluate significant differences in anti-Xa activity and blood concentration, using models adjusted by baseline characteristics. RESULTS: The results suggested anti-Xa activity had better correlation with blood concentrations of apixaban and rivaroxaban than APTT and PT (p < 0.001). Target drug-calibrated anti-Xa activity had better correlation with HPLC-MS results at every dose level and blood collection time (p < 0.001). The expected concentrations (ng/mL) derived from rivaroxaban-calibrated assays of rivaroxaban 10 mg, 15 mg, and 20 mg were about 210, 330, and 270 at peak concentrations, and 28, 44, and 58, respectively, at the trough concentrations. CONCLUSIONS: In this study, we confirm that target drug calibration of anti-Xa activity is a better quantitative detection method for oral direct FXa inhibitors than LMWH-calibrated anti-Xa activity in clinical practice, and expected peak-trough levels are recommended for the Asian population.

18.
J Phys Chem Lett ; 12(24): 5774-5780, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34134488

RESUMO

The chemistry of abiotic synthesis of peptides in the context of their prebiotic origins is a continuing challenge that arises from thermodynamic and kinetic constraints in aqueous media. Here we reported a strategy of microdroplets' mass spectrometry for peptide bonds formed from pure amino acids or a mixture in the presence of phosphoric acids in aqueous microdroplets. In contrast to bulk experiments, the condensation reactions proceed spontaneously under ambient conditions. The microdroplet gave a negative free-energy change (ΔG ∼ -1.1 kcal/mol), and product yields of ∼75% were obtained at the scale of a few milliseconds. Experiments in which nebulization gas pressure and external charge were varied established dependence of peptide production on the droplet size that has a high surface-to-volume ratio. It is concluded that the condensation reactions occurred at or near the air-water interfaces of microdroplets. This aqueous microdroplets approach also provides a route for chemistry synthesis in the prebiotic era.

19.
Artigo em Inglês | MEDLINE | ID: mdl-34165960

RESUMO

Fluorinated carbon (CFx) cathodes have the highest theoretical energy density among lithium primary batteries. However, it is still a huge challenge to be reversible. Here, CFx is proposed as a high-performance cathode material for rechargeable lithium-ion batteries in the extended voltage window of 0.5-4.8 V. Specifically, the fluorinated graphite CF0.88 exhibits an initial specific discharge capacity of 1382 mAh g-1 (2362 Wh kg-1) and a specific discharge capacity of 782 mAh g-1 at the 2nd cycle and maintains a specific discharge capacity of 543 mAh g-1 (508 Wh kg-1) after the 20th cycle. This rechargeable behavior is associated with the conversion of CFx to LiF + C (>1.5 V) and then to Li1+xFC (0.5-1.5 V) during the initial discharge process; Li1+xFC is reversible to LiF + C in the following charge-discharge process (0.5-4.8 V). By extending the voltage window, CFx cathodes can show new electrochemical behaviors. Our research has provided new Li-free cathode materials for rechargeable batteries and insights for improving the performance of a Li/CFx secondary battery.

20.
Life Sci Alliance ; 4(7)2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34078741

RESUMO

The challenge for treating breast cancer (BC) is partly due to long-term dormancy driven by cancer stem cells (CSCs) capable of evading immune response and resist chemotherapy. BC cells show preference for the BM, resulting in poor prognosis. CSCs use connexin 43 (Cx43) to form gap junctional intercellular communication with BM niche cells, fibroblasts, and mesenchymal stem cells (MSCs). However, Cx43 is an unlikely target to reverse BC dormancy because of its role as a hematopoietic regulator. We found N-cadherin (CDH2) and its associated pathways as potential drug targets. CDH2, highly expressed in CSCs, interacts intracellularly with Cx43, colocalizes with Cx43 in BC cells within BM biopsies of patients, and is required for Cx43-mediated gap junctional intercellular communication with BM niche cells. Notably, CDH2 and anti-apoptotic pathways maintained BC dormancy. We thereby propose these pathways as potential pharmacological targets to prevent dormancy and chemosensitize resistant CSCs.

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