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BACKGROUND: Evidence from observational studies indicates that lung cancer screening (LCS) guidelines with high rates of lung cancer (LC) underdiagnosis, and although current screening guidelines have been updated and eligibility criteria for screening have been expanded, there are no studies comparing the efficiency of LCS guidelines in Chinese population. METHODS: Between 2005 and 2022, 31,394 asymptomatic individuals were screened using low-dose computed tomography (LDCT) at our institution. Demographic data and relevant LC risk factors were collected. The efficiency of the LCS for each guideline criteria was expressed as the efficiency ratio (ER). The inclusion rates, eligibility rates, LC detection rates, and ER based on the different eligibility criteria of the four guidelines were comparatively analyzed. The four guidelines were as follows: China guideline for the screening and early detection of lung cancer (CGSL), the National Comprehensive Cancer Network (NCCN), the United States Preventive Services Task Force (USPSTF), and International Early Lung Cancer Action Program (I-ELCAP). RESULTS: Of 31,394 participants, 298 (155 women, 143 men) were diagnosed with LC. For CGSL, NCCN, USPSTF, and I-ELCAP guidelines, the eligibility rates for guidelines were 13.92%, 6.97%, 6.81%, and 53.46%; ERe for eligibility criteria were 1.46%, 1.64%, 1.51%, and 1.13%, respectively; and for the inclusion rates, they were 19.0%, 9.5%, 9.3%, and 73.0%, respectively. LCs which met the screening criteria of CGSL, NCCN, USPSTF, and I-ELCAP guidelines were 29.2%, 16.4%, 14.8%, and 86.6%, respectively. The age and smoking criteria for CGSL were stricter, hence resulting in lower rates of LC meeting the screening criteria. The CGSL, NCCN, and USPSTF guidelines showed the highest underdiagnosis in the 45-49 age group (17.4%), while the I-ELCAP guideline displayed the highest missed diagnosis rate (3.0%) in the 35-39 age group. Males and females significantly differed in eligibility based on the criteria of the four guidelines (P < 0.001). CONCLUSIONS: The I-ELCAP guideline has the highest eligibility rate for both males and females. But its actual efficiency ratio for those deemed eligible by the guideline was the lowest. Whereas the NCCN guideline has the highest ERe value for those deemed eligible by the guideline.
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Detecção Precoce de Câncer , Neoplasias Pulmonares , Tomografia Computadorizada por Raios X , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico , Masculino , China , Feminino , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normas , Pessoa de Meia-Idade , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/normas , Idoso , Guias de Prática Clínica como Assunto , Programas de Rastreamento/métodos , Programas de Rastreamento/normas , AdultoRESUMO
All-inorganic lead halide perovskites (CsPbX3, X = Cl, Br or I) are becoming increasingly important for energy conversion and optoelectronics because of their outstanding performance and enhanced environmental stability. Morphing perovskites into specific shapes and geometries without damaging their intrinsic functional properties is attractive for designing devices and manufacturing. However, inorganic semiconductors are often intrinsically brittle at room temperature, except for some recently reported layered or van der Waals semiconductors. Here, by in situ compression, we demonstrate that single-crystal CsPbX3 micropillars can be substantially morphed into distinct shapes (cubic, L and Z shapes, rectangular arches and so on) without localized cleavage or cracks. Such exceptional plasticity is enabled by successive slips of partial dislocations on multiple [Formula: see text] systems, as evidenced by atomic-resolution transmission electron microscopy and first-principles and atomistic simulations. The optoelectronic performance and bandgap of the devices were unchanged. Thus, our results suggest that CsPbX3 perovskites, as potential deformable inorganic semiconductors, may have profound implications for the manufacture of advanced optoelectronics and energy systems.
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BACKGROUND: The prognosis of lung cancer varies widely, even in cases wherein the tumor stage, genetic mutation, and treatment regimens are the same. Thus, an effective means for risk stratification of patients with lung cancer is needed. PURPOSE: To develop and validate a combined model for predicting progression-free survival and risk stratification in patients with advanced anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC) treated with ensartinib. MATERIAL AND METHODS: We analyzed 203 tumor lesions in 114 patients and evaluated average radiomic feature measures from all lesions at baseline and changes in these features after early treatment (Δradiomic features). Combined models were developed by integrating clinical with radiomic features. The prediction performance and clinical value of the proposed models were evaluated using receiver operating characteristic analysis, calibration curve, decision curve analysis (DCA), and Kaplan-Meier survival analysis. RESULTS: Both the baseline and delta combined models achieved predictive efficacy with a high area under the curve. The calibration curve and DCA indicated the high accuracy and clinical usefulness of the combined models for tumor progression prediction. In the Kaplan-Meier analysis, the delta and baseline combined models, Δradiomic signature, and two selected clinical features could distinguish patients with a higher progression risk within 42 weeks. The delta combined model had the best performance. CONCLUSION: The combination of clinical and radiomic features provided a prognostic value for survival and progression in patients with NSCLC receiving ensartinib. Radiomic-signature changes after early treatment could be more valuable than those at baseline alone.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/tratamento farmacológico , Quinase do Linfoma Anaplásico/genética , Quinase do Linfoma Anaplásico/uso terapêutico , Intervalo Livre de Progressão , PrognósticoRESUMO
The complexes of metal center and nitrogen ligands are the most representative systems for catalyzing hydrogenation reactions in small molecule conversion. Developing heterogeneous catalysts with similar active metal-nitrogen functional centers, nevertheless, still remains challenging. In this work, we demonstrate that the metal-nitrogen coupling in anti-perovskite Co4 N can be effective modulated by Cu doping to form Co3 CuN, leading to strongly promoted hydrogenation process during electrochemical reduction of nitrate (NO3 - RR) to ammonia. The combination of advanced spectroscopic techniques and density functional theory calculations reveal that Cu dopants strengthen the Co-N bond and upshifted the metal d-band towards the Fermi level, promoting the adsorption of NO3 - and *H and facilitating the transition from *NO2 /*NO to *NO2 H/*NOH. Consequently, the Co3 CuN delivers noticeably better NO3 - RR activity than the pristine Co4 N, with optimal Faradaic efficiency of 97 % and ammonia yield of 455.3â mmol h-1 cm-2 at -0.3â V vs. RHE. This work provides an effective strategy for developing high-performance heterogeneous catalyst for electrochemical synthesis.
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BACKGROUND AND PURPOSE: The benefit of endovascular treatment (EVT) for large vessel occlusion in clinical practice in developing countries like China needs to be confirmed. The aim of the study was to determine whether the benefit of EVT for acute ischemic stroke in randomized trials could be generalized to clinical practice in Chinese population. METHODS: We conducted a prospective registry of EVT at 111 centers in China. Patients with acute ischemic stroke caused by imaging-confirmed intracranial large vessel occlusion and receiving EVT were included. The primary outcome was functional independence at 90 days defined as a modified Rankin Scale score of 0 to 2. Outcomes of specific subgroups in the anterior circulation were reported and logistic regression was performed to predict the primary outcome. RESULTS: Among the 1793 enrolled patients, 1396 (77.9%) had anterior circulation large vessel occlusion (median age, 66 [56-73] years) and 397 (22.1%) had posterior circulation large vessel occlusion (median age, 64 [55-72] years). Functional independence at 90 days was reached in 45% and 44% in anterior and posterior circulation groups, respectively. For anterior circulation population, underlying intracranial atherosclerotic disease was identified in 29% of patients, with higher functional independence at 90 days (52% versus 44%; P=0.0122) than patients without intracranial atherosclerotic disease. In the anterior circulation population, after adjusting for baseline characteristics, procedure details, and early outcomes, the independent predictors for functional independence at 90 days were age <66 years (odds ratio [OR], 1.733 [95% CI, 1.213-2.476]), time from onset to puncture >6 hours (OR, 1.536 [95% CI, 1.065-2.216]), local anesthesia (OR, 2.194 [95% CI, 1.325-3.633]), final modified Thrombolysis in Cerebral Infarction 2b/3 (OR, 2.052 [95% CI, 1.085-3.878]), puncture-to-reperfusion time ≤1.5 hours (OR, 1.628 [95% CI, 1.098-2.413]), and National Institutes of Health Stroke Scale score 24 hours after the procedure <11 (OR, 9.126 [95% CI, 6.222-13.385]). CONCLUSIONS: Despite distinct characteristics in the Chinese population, favorable outcome of EVT can be achieved in clinical practice in China. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03370939.
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Procedimentos Endovasculares/métodos , AVC Isquêmico/cirurgia , Idoso , Transtornos Cerebrovasculares/complicações , Transtornos Cerebrovasculares/cirurgia , China , Feminino , Humanos , AVC Isquêmico/etiologia , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Resultado do TratamentoRESUMO
OBJECTIVES: To evaluate the prevalence of Helicobacter pylori infection and risk factors and to serotype the strains in Wuwei, located in north-western China, which has a high incidence of gastric cancer. METHODS: Helicobacter pylori infection was analysed in 21 291 adults by 14 C-urea breath test, and H. pylori antibody were detected in 9183 serum samples by latex immunoturbidimetric method. The correlation of H. pylori infection with demographic-economic, lifestyle factors and medical history among the participants was determined by questionnaire. The antibodies against H. pylori urease, VacA and CagA in serum were determined by dot immunobinding assay. RESULTS: The infection rate of H. pylori was 53.0%, and 90.1% of strains were type I strains. The H. pylori infection rate was higher among farmers (OR = 1.34, 95% CI: 1.19-1.50) and individuals who had a junior high school or higher education level (OR = 1.10, 95% CI: 1.06-1.15), and was lower in older individuals (OR = 0.86, 95% CI: 0.83-0.90), individuals with high income (OR = 0.93, 95% CI: 0.90-0.95), individuals with a habit of eating quickly (OR = 0.93, 95% CI: 0.87-0.99) and individuals who consumed more fruit and vegetables (OR = 0.90, 95% CI: 0.85-0.95). Individuals with history of cholecystitis/cholecystolithiasis, hypertension and asthma were negatively correlated with H. pylori infection (P < 0.05). CONCLUSION: The prevalence of H. pylori infection is high in Wuwei. The major prevalent strain is type I strain. Age, education, occupation, household income, consumption of fruit and vegetables, and habit of eating quickly are independent risk factors for H. pylori infection, which is also associated with individuals with a history of extragastric diseases.
OBJECTIFS: Evaluer la prévalence de l'infection à Helicobacter pylori et les facteurs de risque et déterminer le sérotype des souches à Wuwei, situé dans le nord-ouest de la Chine, où l'incidence du cancer gastrique est élevée. MÉTHODES: L'infection à H. pylori a été analysée chez 21.291 adultes par un test respiratoire à l'urée au 14 C, et des anticorps à H. pylori ont été détectés dans 9.183 échantillons de sérum par une méthode immuno-turbidimétrique au latex. La corrélation entre l'infection à H. pylori et les facteurs démographiques et économiques, le mode de vie et les antécédents médicaux des participants a été déterminée par un questionnaire. Les anticorps contre l'uréase de H. pylori, VacA et CagA dans le sérum ont été déterminés par un test dot par d'immuno-liaison. RÉSULTATS: Le taux d'infection à H. pylori était 53,0% et 90,1% des souches étaient du type I. Le taux d'infection à H. pylori est plus élevé chez les agriculteurs (OR = 1,34 ; IC95%: 1,19 à 1,50) et les personnes qui avaient un niveau d'instruction du premier cycle secondaire ou supérieur (OR = 1,10 ; IC95%: 01,06 à 01,15) et était plus faible chez les personnes âgées (OR = 0,86 ; IC95%: 0,83-0,90), les personnes à revenu élevé (OR = 0,93 ; IC95%: 0,90-0,95), les personnes ayant l'habitude de manger rapidement (OR = 0,93 ; IC9 %: 0,87-0,99) et les individus qui consommaient plus de fruits et de légumes (OR = 0,90 ; IC95%: 0,85-0,95). Les personnes ayant des antécédents de cholécystite/cholécystolithiase, d'hypertension et d'asthme avaient une corrélation négative avec l'infection à H. pylori (p <0,05 ). CONCLUSION: La prévalence de l'infection à H. pylori est élevée à Wuwei. La principale souche répandue est du type I. L'âge, l'éducation, la profession, le revenu du ménage, la consommation de fruits et de légumes et l'habitude de manger rapidement sont des facteurs de risque indépendants d'infection à H. pylori, qui est également associée à des personnes ayant des antécédents de maladies extra-gastriques.
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Infecções por Helicobacter/epidemiologia , Adulto , Anticorpos Antibacterianos/sangue , China/epidemiologia , Estudos de Coortes , Comportamento Alimentar , Feminino , Frutas , Infecções por Helicobacter/sangue , Helicobacter pylori/imunologia , Humanos , Incidência , Renda , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Fatores de Risco , VerdurasRESUMO
OBJECTIVE: To explore the natural history of pulmonary subsolid nodules (SSNs) with different pathological types by deep learning-assisted nodule segmentation. METHODS: Between June 2012 and June 2019, 95 resected SSNs with preoperative long-term follow-up were enrolled in this retrospective study. SSN detection and segmentation were performed on preoperative follow-up CTs using the deep learning-based Dr. Wise system. SSNs were categorized into invasive adenocarcinoma (IAC, n = 47) and non-IAC (n = 48) groups; according to the interval change during the preoperative follow-up, SSNs were divided into growth (n = 68), nongrowth (n = 22), and new emergence (n = 5) groups. We analyzed the cumulative percentages and pattern of SSN growth and identified significant factors for IAC diagnosis and SSN growth. RESULTS: The mean preoperative follow-up was 42.1 ± 17.0 months. More SSNs showed growth or new emergence in the IAC than in the non-IAC group (89.4% vs. 64.6%, p = 0.009). Volume doubling time was non-significantly shorter for IACs than for non-IACs (1436.0 ± 1188.2 vs. 2087.5 ± 1799.7 days, p = 0.077). Median mass doubling time was significantly shorter for IACs than for non-IACs (821.7 vs. 1944.1 days, p = 0.001). Lobulated sign (p = 0.002) and SSN mass (p = 0.004) were significant factors for differentiating IACs. IACs showed significantly higher cumulative growth percentages than non-IACs in the first 70 months of follow-up. The growth pattern of SSNs may conform to the exponential model. The initial volume (p = 0.042) was a predictor for SSN growth. CONCLUSIONS: IACs appearing as SSNs showed an indolent course. The mean growth rate was larger for IACs than for non-IACs. SSNs with larger initial volume are more likely to grow. KEY POINTS: ⢠Invasive adenocarcinomas (IACs) appearing as subsolid nodules (SSNs), with a mean volume doubling time (VDT) of 1436.0 ± 1188.2 days and median mass doubling time (MDT) of 821.7 days, showed an indolent course. ⢠The VDT was shorter for IACs than for non-IACs (1436.0 ± 1188.2 vs. 2087.5 ± 1799.7 days), but the difference was not significant (p = 0.077). The median MDT was significantly shorter for IACs than for non-IACs (821.7 vs. 1944.1 days, p = 0.001). ⢠SSNs with lobulated sign and larger mass (> 390.5 mg) may very likely be IACs. SSNs with larger initial volume are more likely to grow.
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Aprendizado Profundo , Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Nódulo Pulmonar Solitário , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Estudos Retrospectivos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVE: To compare image quality and radiation dose of split-filter TwinBeam dual-energy (SF-TBDE) with those of single-energy images (SECT) in the contrast-enhanced chest computed tomography (CT). METHODS: Two hundred patients who underwent SF-TBDE (n = 100) and SECT (n = 100) contrast-enhanced chest scanning were retrospectively analyzed. The contrast-to-noise ratio (CNR) and figure of merit (FOM)-CNR of 5 structures (lung, aorta, pulmonary artery, thyroid, and erector spinae) were calculated and subjectively evaluated by 2 independent radiologists. Radiation dose was compared using volume CT dose index and size-specific dose estimate. RESULTS: The CNR and FOM-CNR of lung and erector spinae in SF-TBDE were higher than those of SECT (P < 0.001). The differences in the subjective image quality between the 2 groups were not significant (P = 0.244). Volume CT dose index and size-specific dose estimate of SF-TBDE were lower than those of SECT (6.60 ± 1.56 vs 7.81 ± 3.02 mGy, P = 0.001; 9.25 ± 1.60 vs. 10.55 ± 3.54; P = 0.001). CONCLUSIONS: The SF-TBDE CT can provide similar image quality at a lower radiation dose compared with SECT.
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Meios de Contraste , Doses de Radiação , Intensificação de Imagem Radiográfica/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Radiografia Torácica/métodos , Doenças Torácicas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos RetrospectivosRESUMO
A surface-enhanced Raman scattering (SERS)-based immunoassay with gold nanostars (GNSs) is utilized for determination of the subarachnoid hemorrhage (SAH) biomarker glial fibrillary acidic protein (GFAP) at very low concentration levels, which allows for early diagnosis and guides clinical decision-making to treat SAH-induced complications. The Raman reporter 5,5'-dithiobis-2-nitrobenzoic acid (DTNB) modified on GNSs was selected as the SERS tags. The SERS immunoassay was assembled by SERS tag and GFAP probe-immobilized ITO substrate. Therefore, the level of GFAP can be detected by monitoring the characteristic Raman peak intensity of GFAP-conjugated GNSs at 1332 cm-1 with a very low detection limit. Under optimized conditions, the assay can work in the GFAP concentration range from 1 pgâ mL-1 to 1 µgâ mL-1, with a detection limit as low as 0.54 fgâ mL-1. The performance of the SERS immunoassay proven by the detection of GFAP is equivalent to that of the conventional enzyme-linked immunosorbent assay (ELISA). Scheme 1. Schematic illustration of GNSs SERS immunoassay for ultrasensitive dynamic change detection of GFAP. (SAH: Subarachnoid hemorrhage, SCF: Cerebrospinal fluid; GNSs: gold nanostars; SERS: surface-enhanced Raman scattering; GFAP: glial fibrillary acidic protein).
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Técnicas Biossensoriais/métodos , Proteína Glial Fibrilar Ácida/metabolismo , Ouro/química , Imunoensaio/métodos , Análise Espectral Raman/métodos , Ensaio de Imunoadsorção Enzimática , HumanosRESUMO
OBJECTIVE: To investigate the natural history of persistent pulmonary pure ground-glass nodules (pGGNs) with deep learning-assisted nodule segmentation. METHODS: Between January 2007 and October 2018, 110 pGGNs from 110 patients with 573 follow-up CT scans were included in this retrospective study. pGGN automatic segmentation was performed on initial and all follow-up CT scans using the Dr. Wise system based on convolution neural networks. Subsequently, pGGN diameter, density, volume, mass, volume doubling time (VDT), and mass doubling time (MDT) were calculated automatically. Enrolled pGGNs were categorized into growth, 52 (47.3%), and non-growth, 58 (52.7%), groups according to volume growth. Kaplan-Meier analyses with the log-rank test and Cox proportional hazards regression analysis were conducted to analyze the cumulative percentages of pGGN growth and identify risk factors for growth. RESULTS: The mean follow-up period of the enrolled pGGNs was 48.7 ± 23.8 months. The median VDT of the 52 pGGNs having grown was 1448 (range, 339-8640) days, and their median MDT was 1332 (range, 290-38,912) days. The 12-month, 24.7-month, and 60.8-month cumulative percentages of pGGN growth were 10%, 25.5%, and 51.1%, respectively, and they significantly differed among the initial diameter, volume, and mass subgroups (all p < 0.001). The growth pattern of pGGNs may conform to the exponential model. Lobulated sign (p = 0.044), initial mean diameter (p < 0.001), volume (p = 0.003), and mass (p = 0.023) predicted pGGN growth. CONCLUSIONS: Persistent pGGNs showed an indolent course. Deep learning can assist in accurately elucidating the natural history of pGGNs. pGGNs with lobulated sign and larger initial diameter, volume, and mass are more likely to grow. KEY POINTS: ⢠The pure ground-glass nodule (pGGN) segmentation accuracy of the Dr. Wise system based on convolution neural networks (CNNs) was 96.5% (573/594). ⢠The median volume doubling time (VDT) of 52 pure ground-glass nodules (pGGNs) having grown was 1448 days (range, 339-8640 days), and their median mass doubling time (MDT) was 1332 days (range, 290-38,912 days). The mean time to growth in volume was 854 ± 675 days (range, 116-2856 days). ⢠The 12-month, 24.7-month, and 60.8-month cumulative percentages of pGGN growth were 10%, 25.5%, and 51.1%, respectively, and they significantly differed among the initial diameter, volume, and mass subgroups (all p values < 0.001). The growth pattern of pure ground-glass nodules may conform to exponential model.
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Aprendizado Profundo , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Feminino , Seguimentos , Humanos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Estudos Retrospectivos , Fatores de Risco , TempoRESUMO
Due to the quantum properties of light, solar background radiation (SBR) is the main source of noise in daytime wind observations of spaceborne Doppler wind lidars (DWLs). In previous works, the impact of SBR on the observation accuracy of spaceborne lidars was assessed mainly using the default or worst-case scenarios. We assessed the impact of SBR on the observations of spaceborne DWLs using the global distributions of SBR in summer and winter, which were obtained based on their orbit parameters, view geometry and optical parameters. Three experiments illustrate that the uncertainty in wind observations increases with an increase in the quantiles of SBR. The uncertainties of the whole profiles of wind are greater than 2 m s-1 in the troposphere and 3 m s-1 in the stratosphere when the quantile of the SBR is greater than 85% in summer and 95% in winter, which do not satisfy the accuracy expectations of the European Space Agency (ESA) for spaceborne DWLs. The facts indicate that the impact of SBR cannot be negligible for the observations of spaceborne DWLs. Based on the orbit parameters, view geometry, and optical parameters of new spaceborne DWLs, engineers can assess the impact of SBR on the accuracy of wind observations from a global perspective using the method proposed in this paper.
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Air promoted intermolecular annulation of thiophenols with alkynes, leading to complex benzothiophenes, is reported. This atom-economical reaction is performed in the absence of any catalyst, chemical oxidant and additive. Only a solvent and an air atmosphere were required. A plausible radical involved mechanism is proposed.
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Multielement solid solution alloys are intrinsically disordered on the atomic scale, and many of their advanced properties originate from the local structural characteristics. The local structure of a NiCoCr solid solution alloy is measured with x-ray or neutron total scattering and extended x-ray absorption fine structure (EXAFS) techniques. The atomic pair distribution function analysis does not exhibit an observable structural distortion. However, an EXAFS analysis suggests that the Cr atoms are favorably bonded with Ni and Co in the solid solution alloys. This short-range order (SRO) may make an important contribution to the low values of the electrical and thermal conductivities of the Cr-alloyed solid solutions. In addition, an EXAFS analysis of Ni ion irradiated samples reveals that the degree of SRO in NiCoCr alloys is enhanced after irradiation.
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Chemotherapy has always been one of the most effective ways in combating human glioma. However, the high metastatic potential and resistance toward standard chemotherapy severely hindered the chemotherapy outcomes. Hence, searching effective chemotherapy drugs and clarifying its mechanism are of great significance. Salinomycin an antibiotic shows novel anticancer potential against several human tumors, including human glioma, but its mechanism against human glioma cells has not been fully elucidated. In the present study, we demonstrated that salinomycin treatment time- and dose-dependently inhibited U251 and U87 cells growth. Mechanically, salinomycin-induced cell growth inhibition against human glioma was mainly achieved by induction of G1-phase arrest via triggering reactive oxide species (ROS)-mediated DNA damage, as convinced by the activation of histone, p53, p21 and p27. Furthermore, inhibition of ROS accumulation effectively attenuated salinomycin-induced DNA damage and G1 cell cycle arrest, and eventually reversed salinomycin-induced cytotoxicity. Importantly, salinomycin treatment also significantly inhibited the U251 tumor xenograft growth in vivo through triggering DNA damage-mediated cell cycle arrest with involvement of inhibiting cell proliferation and angiogenesis. The results above validated the potential of salinomycin-based chemotherapy against human glioma.
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Dano ao DNA/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Glioma/metabolismo , Piranos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Dano ao DNA/fisiologia , Relação Dose-Resposta a Droga , Pontos de Checagem da Fase G1 do Ciclo Celular/fisiologia , Glioma/tratamento farmacológico , Glioma/patologia , Humanos , Masculino , Camundongos , Camundongos Nus , Piranos/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
Catalytic amounts of TBHP (15 mol%) promoted tribromomethylation of activated alkenes has been developed. This method provided a metal-free aerobic way to construct tribromomethylated 2-oxindoles from the reaction of readily available N-arylacrylamides with CBr4via a proposed tandem radical cyclization process. Air is used as an efficient terminal oxidant in this transformation. The formation of 1,1-dibromoolefin derivatives was also realized at higher temperature under neat conditions.
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A simple and practical carbon tetrabromide promoted intramolecular aerobic oxidative dehydrogenative coupling reaction has been developed to provide a straightforward ring closure protocol for 2-aryloxybenzaldehydes to furnish xanthones. The reaction was performed under metal-, additive- and solvent-free conditions with good tolerance of functional groups. The present method is also applicable to the synthesis of fluorenones by using 2-arylbenzaldehydes as substrates. Preliminary studies of the reaction mechanism indicated that the reaction may proceed through a radical pathway.
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It has been shown that concentrated solid solution alloys possess unusual electronic, magnetic, transport, mechanical and radiation-resistant properties that are directly related to underlying chemical complexity. Because every atom experiences a different local atomic environment, the formation and migration energies of vacancies and interstitials in these alloys exhibit a distribution, rather than a single value as in a pure metal or dilute alloy. Using ab initio calculations based on density functional theory and special quasirandom structures, we have characterized the distribution of defect formation energy and migration barrier in four Ni-based solid-solution alloys: Ni0.5Co0.5, Ni0.5Fe0.5, Ni0.8Fe0.2, and Ni0.8Cr0.2. As defect formation energies in finite-size models depend sensitively on the elemental chemical potential, we have developed a computationally efficient method for determining it which takes into account the global composition and the local short-range order. In addition we have compared the results of our ab initio calculations to those obtained from available embedded atom method (EAM) potentials. Our results indicate that the defect formation and migration energies are closely related to the specific atoms in the structure, which further determines the elemental diffusion properties. Different EAM potentials yield different features of defect energetics in concentrated alloys, pointing to the need for additional potential development efforts in order to allow spatial and temporal scale-up of defect and simulations, beyond those accessible to ab initio methods.
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Density functional theory (DFT) calculation is employed to study the adsorption properties of Pb and Cu on recently synthesized two-dimensional materials MXenes, including Ti3C2, V2C1 and Ti2C1. The influence of surface decoration with functional groups such as H, OH and F have also been investigated. Most of these studied MXenes exhibit excellent capability to adsorb Pb and Cu, especially the adsorption capacity of Pb on Ti2C1 is as high as 2560 mg g(-1). Both the binding energies and the adsorption capacities are sensitive to the functional groups attached to the MXenes' surface. Ab initio molecular dynamics (ab-init MD) simulation confirms that Ti2C1 remains stable at room temperature after adsorbing Pb atoms. Our calculations imply that these newly emerging two-dimensional MXenes are promising candidates for wastewater treatment and ion separation.
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OBJECTIVE. Appropriate radiologic interpretation of screening CT can minimize unnecessary workup and intervention. This is particularly challenging in the baseline round. We report on the quality assurance process we developed for the International Early Lung Cancer Action Program. MATERIALS AND METHODS. After initial training at the coordinating center, radiologists at 10 participating institutions and at the center independently interpreted the first 100 baseline screenings. The radiologist at the institutions had access to the center interpretations before issuing the final reports. After the first 100 screenings, the interpretations were jointly discussed. This report summarizes the results of the initial 100 dual interpretations at the 10 institutions. RESULTS. The final institution interpretations agreed with the center in 895 of the 1000 interpretations. Compared with the center, the frequency of positive results was higher at eight of the 10 institutions. The most frequent reason of discrepant interpretations was not following the protocol (n = 55) and the least frequent was not identifying a nodule (n = 3). CONCLUSION. The quality assurance process helped focus educational programs and provided an excellent vehicle for review of the protocol with participating physicians. It also suggests that the rate of positive results can be reduced by such measures.
Assuntos
Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/normas , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Controle de QualidadeRESUMO
OBJECTIVE: To report the results of low-dose computed tomography (LDCT) screening for early lung cancer in 4 690 asymptomatic participants at the Cancer Hospital, Chinese Academy of Medical Sciences between July 2007 and June 2012. METHODS: After informed consent and questionnaire forms were obtained, 4 690 asymptomatic participants ≥ 40 years underwent chest low dose spiral CT scanning. According to the National Comprehensive Cancer Network (NCCN) guideline for lung cancer screening (version 1.1, 2012), all participants were assigned to three groups, namely high-risk, moderate-risk and low-risk groups. In terms of gender, smoking history and second-hand tobacco smoking exposure history, two other groups named male and female never-smoker groups who were exposed to second-hand tobacco smoking were designated. The positive results were identified as at least one solid or part-solid nodule measuring ≥ 5 mm, or non-solid nodule ≥ 8 mm in diameter. LDCT scanning protocol, criteria of management according to the size and consistency of pulmonary nodules were compliant with the International Early Lung Cancer Active Program (I-ELCAP). TNM staging of all lung cancers were based on the clinical evidence and pathological findings. RESULTS: In various risk status group of the participants, the percentage of positive results of baseline CT were 27.0% (86/319), 19.3% (199/1 029) and 11.3% (377/3 342), respectively. A total of 26 participants (27 lesions) were diagnosed as lung cancer (11 in men, 15 in women). The detection rate of lung cancer was 0.6% (26/4 690). Besides a SCLC (limited-disease, LD), 25 cases (76.0%) were stage I including 24 NSCLC and one cacinoid on baseline LDCT and the surgical resection rate was 88.5% (23/26). The diameter of resected cancers was 6.9-29.5 mm (median, 16.3 mm). For female never smokers aged 40 years or older who were exposed to second-hand smoking, the detection rate of lung cancer was higher than that of the high-risk and male never smokers who were exposed to second-hand smoking (1.4% vs. 0.9%, 0.4%). CONCLUSIONS: The results indicate that LDCT can detect small lung cancers and most of the cancers are detected at an early stage. Emphasis should be placed on the non-smoking female individuals who are exposed to second-hand smoking in China.