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1.
J Am Chem Soc ; 146(20): 14048-14057, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38713054

RESUMO

Optimization of active sites and stability under irradiation are important targets for sorbent materials that might be used for iodine (I2) storage. Herein, we report the direct observation of I2 binding in a series of Cu(II)-based isostructural metal-organic frameworks, MFM-170, MFM-172, MFM-174, NJU-Bai20, and NJU-Bai21, incorporating various functional groups (-H, -CH3, - NH2, -C≡C-, and -CONH-, respectively). MFM-170 shows a reversible uptake of 3.37 g g-1 and a high packing density of 4.41 g cm-3 for physiosorbed I2. The incorporation of -NH2 and -C≡C- moieties in MFM-174 and NJU-Bai20, respectively, enhances the binding of I2, affording uptakes of up to 3.91 g g-1. In addition, an exceptional I2 packing density of 4.83 g cm-3 is achieved in MFM-174, comparable to that of solid iodine (4.93 g cm-3). In situ crystallographic studies show the formation of a range of supramolecular and chemical interactions [I···N, I···H2N] and [I···C≡C, I-C═C-I] between -NH2, -C≡C- sites, respectively, and adsorbed I2 molecules. These observations have been confirmed via a combination of solid-state nuclear magnetic resonance, X-ray photoelectron, and Raman spectroscopies. Importantly, γ-irradiation confirmed the ultraresistance of MFM-170, MFM-174, and NJU-Bai20 suggesting their potential as efficient sorbents for cleanup of radioactive waste.

2.
Ann Surg Oncol ; 31(2): 872-882, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37962740

RESUMO

BACKGROUND: This study aimed to evaluate the dynamic impact of the micropapillary (MIP) component on local recurrence (LR), distant metastasis (DM), and multiple recurrence (MR) of pathological stage IA3 lung adenocarcinoma. METHODS: Between July 2012 and July 2020, a total of 351 patients at two medical institutions were enrolled in this study. Cumulative incidence of curves, dynamic risk curves, and time-dependent multivariate analysis was performed to evaluate the effect of the MIP component on patients. RESULTS: The 5-year cumulative incidence of total recurrence with or without an MIP component was 34.2% and 12.3%, respectively (p = 0.001). In three recurrence patterns, our findings revealed that the 5-year cumulative incidence of LR (p = 0.048) and DM (p = 0.005) was higher in the 'MIP-present' group than in the 'MIP-absent' group. In the dynamic recurrence curve, the risk of the three recurrence patterns was different and varied over time between the two groups, especially in DM. Moreover, the dynamic cumulative event curve showed that after 1, 2, and 3 years of survival, the cumulative incidence of DM in the group with MIP continued to be higher than that in the group without MIP (all p < 0.05). Time-dependent Cox regression analysis indicated that the MIP component continued to be an independent risk factor for the cumulative incidence of DM in patients with 3-year survival. CONCLUSIONS: Of the three recurrence patterns, the MIP component mainly aggravated the risk of DM in patients with pathological stage IA3 lung adenocarcinoma, which persisted for 3 years.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Pulmonares , Humanos , Estudos Retrospectivos , Neoplasias Pulmonares/patologia , Adenocarcinoma/cirurgia , Adenocarcinoma/patologia , Estadiamento de Neoplasias , Recidiva Local de Neoplasia/cirurgia , Recidiva Local de Neoplasia/patologia , Adenocarcinoma de Pulmão/patologia , Prognóstico
3.
Chemistry ; 30(7): e202303289, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37899311

RESUMO

Formamides are important feedstocks for the manufacture of many fine chemicals. State-of-the-art synthesis of formamides relies on the use of an excess amount of reagents, giving copious waste and thus poor atom-economy. Here, we report the first example of direct synthesis of N-formamides by coupling two challenging reactions, namely reductive amination of carbonyl compounds, particularly biomass-derived aldehydes and ketones, and fixation of CO2 in the presence of H2 over a metal-organic framework supported ruthenium catalyst, Ru/MFM-300(Cr). Highly selective production of N-formamides has been observed for a wide range of carbonyl compounds. Synchrotron X-ray powder diffraction reveals the presence of strong host-guest binding interactions via hydrogen bonding and parallel-displaced π⋅⋅⋅π interactions between the catalyst and adsorbed substrates facilitating the activation of substrates and promoting selectivity to formamides. The use of multifunctional porous catalysts to integrate CO2 utilisation in the synthesis of formamide products will have a significant impact in the sustainable synthesis of feedstock chemicals.

4.
BMC Public Health ; 24(1): 1625, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890613

RESUMO

OBJECTIVE: This study aimed to systematically review epidemiological evidence on associations between screen time exposure and myopia in children and adolescents, and to quantitatively evaluate summary effect estimates from existing literature. METHOD: There were three online databases including PubMed, Embase, and Web of Science, for epidemiological studies on screen time exposure and myopia published before June 1, 2023. The risk of bias was assessed by the Newcastle Ottawa Scale (NOS) checklist. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to evaluate the correlation between screen time exposure and myopia using random or fixed-effect models by exposure type (categorical/continuous). We also performed subgroup analysis by screen device type, study quality, geographic region, and research period. RESULTS: We searched 7,571 records from three databases and identified 19 eligible studies, including 14 high-quality studies and 5 moderate-quality studies. Meta-analyses suggested that there was a statistically significant correlation between screen time (high vs. low) and myopia. The pooled ORs with 95%CIs were respectively 2.24 (1.47-3.42) for cross-sectional studies, and 2.39 (2.07-2.76) for cohort studies. We also found a significant association between continuous exposure to screen time (per 1 h/d increase) and myopia in cohort studies. The pooled ORs with 95%CIs were 1.07 (1.01-1.13). In subgroup analysis stratified by screen device type in cross-sectional studies, screen time exposures from computers (categorical: OR = 8.19, 95%CI: 4.78-14.04; continuous: OR = 1.22, 95%CI: 1.10-1.35) and televisions (categorical: OR = 1.46, 95%CI: 1.02-2.10) were associated with myopia, while smartphones were not. Although publication bias was detected, the pooled results did not show significant changes after adjustment using the trim and fill method. CONCLUSION: Our findings support that screen time exposure was significantly associated with myopia in children and adolescents. Notably, screen time exposure from computers may have the most significant impact on myopia.


Assuntos
Miopia , Tempo de Tela , Humanos , Miopia/epidemiologia , Criança , Adolescente
5.
Int J Mol Sci ; 25(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38612806

RESUMO

N6-methyladenosine (m6A) is essential for RNA metabolism in cells. The YTH domain, conserved in the kingdom of Eukaryotes, acts as an m6A reader that binds m6A-containing RNA. In plants, the YTH domain is involved in plant hormone signaling, stress response regulation, RNA stability, translation, and differentiation. However, little is known about the YTH genes in tea-oil tree, which can produce edible oil with high nutritional value. This study aims to identify and characterize the YTH domains within the tea-oil tree (Camellia chekiangoleosa Hu) genome to predict their potential role in development and stress regulation. In this study, 10 members of the YTH family containing the YTH domain named CchYTH1-10 were identified from C. chekiangoleosa. Through analysis of their physical and chemical properties and prediction of subcellular localization, it is known that most family members are located in the nucleus and may have liquid-liquid phase separation. Analysis of cis-acting elements in the CchYTH promoter region revealed that these genes could be closely related to abiotic stress and hormones. The results of expression profiling show that the CchYTH genes were differentially expressed in different tissues, and their expression levels change under drought stress. Overall, these findings could provide a foundation for future research regarding CchYTHs in C. chekiangoleosa and enrich the world in terms of epigenetic mark m6A in forest trees.


Assuntos
Camellia , Camellia/genética , Diferenciação Celular , Secas , RNA , Chá
6.
J Am Chem Soc ; 145(12): 6730-6740, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36916242

RESUMO

The reactions of H2, CO2, and CO gas mixtures on the surface of Cu at 200 °C, relevant for industrial methanol synthesis, are investigated using a combination of ambient pressure X-ray photoelectron spectroscopy (AP-XPS) and atmospheric-pressure near edge X-ray absorption fine structure (AtmP-NEXAFS) spectroscopy bridging pressures from 0.1 mbar to 1 bar. We find that the order of gas dosing can critically affect the catalyst chemical state, with the Cu catalyst maintained in a metallic state when H2 is introduced prior to the addition of CO2. Only on increasing the CO2 partial pressure is CuO formation observed that coexists with metallic Cu. When only CO2 is present, the surface oxidizes to Cu2O and CuO, and the subsequent addition of H2 partially reduces the surface to Cu2O without recovering metallic Cu, consistent with a high kinetic barrier to H2 dissociation on Cu2O. The addition of CO to the gas mixture is found to play a key role in removing adsorbed oxygen that otherwise passivates the Cu surface, making metallic Cu surface sites available for CO2 activation and subsequent conversion to CH3OH. These findings are corroborated by mass spectrometry measurements, which show increased H2O formation when H2 is dosed before rather than after CO2. The importance of maintaining metallic Cu sites during the methanol synthesis reaction is thereby highlighted, with the inclusion of CO in the gas feed helping to achieve this even in the absence of ZnO as the catalyst support.

7.
J Am Chem Soc ; 145(38): 20792-20800, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37722104

RESUMO

Conversion of methane (CH4) to ethylene (C2H4) and/or acetylene (C2H2) enables routes to a wide range of products directly from natural gas. However, high reaction temperatures and pressures are often required to activate and convert CH4 controllably, and separating C2+ products from unreacted CH4 can be challenging. Here, we report the direct conversion of CH4 to C2H4 and C2H2 driven by non-thermal plasma under ambient (25 °C and 1 atm) and flow conditions over a metal-organic framework material, MFM-300(Fe). The selectivity for the formation of C2H4 and C2H2 reaches 96% with a high time yield of 334 µmol gcat-1 h-1. At a conversion of 10%, the selectivity to C2+ hydrocarbons and time yield exceed 98% and 2056 µmol gcat-1 h-1, respectively, representing a new benchmark for conversion of CH4. In situ neutron powder diffraction, inelastic neutron scattering and solid-state nuclear magnetic resonance, electron paramagnetic resonance (EPR), and diffuse reflectance infrared Fourier transform spectroscopies, coupled with modeling studies, reveal the crucial role of Fe-O(H)-Fe sites in activating CH4 and stabilizing reaction intermediates via the formation of an Fe-O(CH3)-Fe adduct. In addition, a cascade fixed-bed system has been developed to achieve online separation of C2H4 and C2H2 from unreacted CH4 for direct use. Integrating the processes of CH4 activation, conversion, and product separation within one system opens a new avenue for natural gas utility, bridging the gap between fundamental studies and practical applications in this area.

8.
Ann Surg Oncol ; 30(9): 5843-5853, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37219654

RESUMO

INTRODUCTION: The study investigated the synergistic effect of the micropapillary (MIP) component and consolidation-to-tumor ratio (CTR) on the recurrence and survival of patients with pathologic stage IA3 lung adenocarcinoma. METHODS: We enrolled 419 patients confirmed pathological stage IA3 adenocarcinoma from four institutions. Kaplan-Meier analysis was performed to examine the value of the MIP component and CTR on relapse-free survival (RFS) and overall survival (OS). The cumulative recurrence between different stages was analyzed by using cumulative event curves. RESULTS: RFS (P < 0.0001) and OS (P = 0.008) in the presence of the MIP group were significantly lower than those in the absence of the MIP group, and CTR > 5 only reduced RFS (P = 0.0004), but not OS (P = 0.063), in the patients. In addition, the prognosis of patients with both the MIP component and CTR > 5 was worse than that of those without the MIP component or CTR ≤ 5. Therefore, we established new subtypes of the stage IA3: IA3a, IA3b, and IA3c. RFS and OS for IA3c staging were significantly lower than those for IA3a and IA3b. For IA3c, the cumulative incidence of local recurrence (P < 0.001) and that of distant metastasis (P = 0.004) were significantly higher than those for IA3a and IA3b. CONCLUSIONS: The MIP component combined with CTR > 0.5 can effectively predict the prognosis of patients with pathological stage IA3 lung adenocarcinoma and may offer more detailed recurrence and survival information according to the established subtype stage of IA3.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Recidiva Local de Neoplasia/cirurgia , Recidiva Local de Neoplasia/patologia , Adenocarcinoma de Pulmão/patologia , Prognóstico , Estudos Retrospectivos
9.
Surg Endosc ; 37(10): 7698-7708, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37563344

RESUMO

BACKGROUND: The effects of minimally invasive total mesoesophageal excision (MITME) on the long-term prognosis of locally advanced esophageal squamous cell carcinoma (ESCC) remain unknown. The objective of this study was to compare the static and dynamic failure patterns of MITME and minimally invasive esophagectomy (MIE) for locally advanced ESCC. METHODS: We use propensity score matching (PSM) method to analyze the postoperative failure patterns of the two groups. Cumulative event curves were analyzed for cumulative incidence of failure between different groups, and independent prognostic factors were assessed using time-dependent multivariate analyses. The risk of dynamic failure calculated at 12-month intervals was compared between the two groups using the lifetime table. RESULTS: A total of 366 ESCC patients were studied by 1:1 PSM for T stage and TNM stage (MITME group, n = 183; MIE group, n = 183). In the matched cohort, there was significant differences between the MITME and MIE groups in the failure pattern of regional lymph node recurrence (0.5 vs 3.8%, P = 0.032) and non-tumor death (10.9 vs 31.7%, P < 0.001). The cumulative event curve found that the 5-year cumulative failure rate was lower in the MITME group than in the MIE group (3.3 vs 17.1%, P = 0.026) after 5 years of survival. In addition, multivariate Cox regression analysis showed that MIE was an independent poor prognostic factor for a high cumulative failure rate in locally advanced ESCC patients at 5 years after surgery (HR:4.110; 95% CI 1.047-16.135; P = 0.043). The dynamic risk curve showed that the MITME group had a lower risk of failure within 5 years after surgery than the MIE group. CONCLUSION: Considering that MITME can significantly improve the postoperative failure pattern and the benefit lasts for at least 5 years, it is feasible to use MITME as a treatment for locally advanced ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/cirurgia , Neoplasias Esofágicas/patologia , Seguimentos , Estudos de Coortes , Esofagectomia/métodos , Resultado do Tratamento , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos
10.
World J Surg ; 47(4): 1003-1017, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36633646

RESUMO

INTRODUCTION: The potential association between severe postoperative complications (SPC) and the oncological outcomes of esophageal squamous cell carcinoma (ESCC) patients according to the different Naples Prognostic Score (NPS) of the inflammatory nutritional status after minimally invasive esophagectomy (MIE) is unclear. METHODS: Kaplan-Meier survival analysis was used to evaluate overall survival (OS) and disease-free survival (DFS) between with or without SPC (Clavien-Dindo grade ≥ III) in low NPS status (NPS = 0 or 1) and high NPS status (NPS = 2 or 3 or 4) patients. Cox multivariable analysis was carried out to analyze the various independent factors of OS and DFS, and a nomogram based on SPC was established. RESULTS: A total of 20.7% (125/604) ESCC patients developed SPC after MIE. Patients with SPC exhibited poor 5-year OS and DFS compared to those without SPC (all P < 0.001). Further analysis revealed that SPC significantly reduced OS and DFS in patients with high NPS status (all P < 0.001) but had little effect on the prognosis of patients with low NPS status (all P > 0.05). Multivariable Cox analysis revealed that SPC could be an independent influence indicator for OS and DFS in patients with high NPS status. Therefore, a novel nomogram combining SPC and tumor-node-metastasis (TNM) staging has been developed, which was found to be relatively more accurate in predicting OS and DFS than TNM staging alone. CONCLUSION: Severe complications can adversely affect the long-term oncological outcome of ESCC patients with high systemic inflammatory response and malnutrition after MIE.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/cirurgia , Neoplasias Esofágicas/patologia , Estado Nutricional , Esofagectomia/efeitos adversos , Prognóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos
11.
BMC Psychiatry ; 23(1): 304, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37127572

RESUMO

BACKGROUND: Non-suicidal self-injury behavior (NSSI) is a common mental health threat among adolescents. Poor parent-child relationship (PCR) and problematic mobile phone use (PMPU) are risk factors for NSSI. We aimed to explore the impact of PCR quality, PMPU, and their interaction effects on NSSI among adolescents in China, as well as the sex difference. METHOD: A survey was conducted among school students in 4 provinces in China between 2017 and 2018. The study included 14,500 valid participants. The students' general demographic characteristics was collected, and further data on PCR quality, PMPU, and NSSI were obtained through self-rated questionnaire. Chi-square test, binomial logistic regression models, and the Andersson Excel were used for data analysis. RESULTS: The 12-month prevalence of NSSI was 27.3%. Lower PCR quality and PMPU were significantly associated with NSSI, respectively. The low PCR + yes PMPU group had the greatest association with NSSI, followed by the high PCR + yes PMPU group, low PCR + no PMPU group. Moreover, in low father-child relationship + yes PMPU group, females had a higher risk of NSSI than males; in high mother-child relationship + yes PMPU group, females had a higher risk of NSSI than males. Additive interaction analysis indicated that mother-child relationship quality and PMPU were associated with increased risks of NSSI, in the subgroup of males. CONCLUSIONS: The findings underline the importance of simultaneously studying the quality of PCR and PMPU for a comprehensive understanding of NSSI behavior, and especially highlights the significance of maternal relationship quality.


Assuntos
Uso do Telefone Celular , Comportamento Autodestrutivo , Humanos , Masculino , Feminino , Adolescente , Comportamento Autodestrutivo/epidemiologia , Saúde Mental , Relações Pais-Filho , Relações Mãe-Filho , China/epidemiologia
12.
BMC Ophthalmol ; 23(1): 135, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37013536

RESUMO

BACKGROUND: This study aimed to investigate the relationship between sleep-wake schedules and self-reported myopia in the pediatric population. METHODS: In this cross-sectional study in 2019, school-aged children and adolescents in the Baoan District of Shenzhen City were sampled using a stratified cluster sampling approach. Sleep-wake schedules of children were determined by a self-administered questionnaire. The age that participants first reported using myopia correction glasses or contact lenses was used to identify those with myopia. Pearson χ2 test was used to examine differences in myopia prevalence among participants with different characteristics. Multivariate logistic regression, adjusted for potential confounding variables, was applied to examine the relationship between sleep-wake schedule and risk of self-reported myopia, and a stratification analysis by school grade was also performed. RESULTS: A total of 30,188 students were recruited. In this study, the overall prevalence of myopia was 49.8%, with prevalence rates of 25.6%, 62.4%, and 75.7% for primary, junior high, and senior high school students, respectively. Students with irregular sleep-wake times reported a higher prevalence of myopia than those with regular sleep-wake times. Nighttime sleep duration of < 7 hours/day (h/d) (OR = 1.27, 95%CI: 1.17-1.38), no daytime nap (OR = 1.10, 95%CI: 1.03-1.18), irregular weekday bedtime (OR = 1.11, 95%CI: 1.05-1.17), irregular weekday wake time (OR = 1.21, 95%CI: 1.12-1.30), weekend bedtime delayed > = 1 h/d (OR = 1.20, 95%CI: 1.11-1.29, P < 0.001), weekend wake time delayed > = 1 h/d (OR = 1.11, 95%CI: 1.03-1.19), irregular sleep-wake time on weekdays (OR = 1.13, 95%CI: 1.07-1.19), and social jetlag > = 1 h (OR = 1.08, 95%CI: 1.03-1.14) were likely to be associated with increased risks of self-reported myopia after adjusting age, sex, grade, parental education level, family income, parental myopia, academic record, and academic workload. When stratified by school grade, we observed that nighttime sleep duration < 7 h/d, no daytime naps, and irregular sleep-wake time on weekdays were significantly associated with self-reported myopia in primary school students. CONCLUSION: Insufficient sleep and irregular sleep-wake schedules can increase the risk of self-reported myopia in children and adolescents.


Assuntos
População do Leste Asiático , Miopia , Humanos , Criança , Adolescente , Estudos Transversais , Sono , Inquéritos e Questionários , Miopia/epidemiologia
13.
J Public Health (Oxf) ; 45(1): 75-83, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35226755

RESUMO

BACKGROUND: We aimed to explore the relationship between body mass index (BMI) and body weight perception (BWP) with suicidal behaviors among mainland Chinese adolescents. METHODS: A nationally representative sample (N = 10 110) of Chinese adolescents was assessed in this study. Suicidal behaviors (ideation, plan and attempt) were evaluated by four self-reported questions. Generalized linear mixed model was used to estimate the adjusted odds ratios (ORs) for the association between BWP/BMI with suicidal behaviors. RESULTS: The prevalence of suicidal ideation, suicidal plan and suicidal attempt was 12, 5 and 2.1%, respectively. After adjusting potential covariates, perceiving oneself as obese was significantly associated with increased risks of suicidal ideation (OR: 2.4, 95% confidence intervals, CI: 1.6-4.0, P = 0.001), suicidal plan (OR: 3.1, 95% CI: 1.5-6.3, P = 0.002) and suicidal attempt (OR: 3.7, 95% CI: 1.5-9.1, P = 0.001) compared with perceiving as normal weight among male adolescents; the effect attenuated to null among female adolescents. Perceiving oneself as underweight and overweight both exhibited significant adverse effect on suicidal behaviors (only suicidal ideation and suicidal plan) compared with perceiving oneself as normal weight among male adolescents, but not among female adolescents. The actual measured BMI was not significantly associated with suicidal behaviors among neither gender. CONCLUSIONS: Self-perception of their body image rather than actual measured weight may have a gender-specific adverse effect on suicidal behaviors among Chinese adolescents.


Assuntos
Comportamento do Adolescente , Índice de Massa Corporal , Obesidade , Ideação Suicida , Adolescente , Feminino , Humanos , Masculino , População do Leste Asiático , Fatores de Risco , Tentativa de Suicídio , Peso Corporal , Autoimagem
14.
J Am Chem Soc ; 144(19): 8624-8632, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35533381

RESUMO

The presence of active sites in metal-organic framework (MOF) materials can control and affect their performance significantly in adsorption and catalysis. However, revealing the interactions between the substrate and active sites in MOFs at atomic precision remains a challenging task. Here, we report the direct observation of binding of NH3 in a series of UiO-66 materials containing atomically dispersed defects and open Cu(I) and Cu(II) sites. While all MOFs in this series exhibit similar surface areas (1111-1135 m2 g-1), decoration of the -OH site in UiO-66-defect with Cu(II) results in a 43% enhancement of the isothermal uptake of NH3 at 273 K and 1.0 bar from 11.8 in UiO-66-defect to 16.9 mmol g-1 in UiO-66-CuII. A 100% enhancement of dynamic adsorption of NH3 at a concentration level of 630 ppm from 2.07 mmol g-1 in UiO-66-defect to 4.15 mmol g-1 in UiO-66-CuII at 298 K is observed. In situ neutron powder diffraction, inelastic neutron scattering, and electron paramagnetic resonance, solid-state nuclear magnetic resonance, and infrared spectroscopies, coupled with modeling reveal that the enhanced NH3 uptake in UiO-66-CuII originates from a {Cu(II)···NH3} interaction, with a reversible change in geometry at Cu(II) from near-linear to trigonal coordination. This work represents the first example of structural elucidation of NH3 binding in MOFs containing open metal sites and will inform the design of new efficient MOF sorbents by targeted control of active sites for NH3 capture and storage.

15.
Surg Endosc ; 36(11): 8326-8339, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35556169

RESUMO

BACKGROUND: Non-textbook outcome (non-TO) represents a new prognostic evaluation index for surgical oncology. The present study aimed to develop new nomograms based on non-TO to predict the mortality and recurrence rate in patients with esophageal squamous cell cancer (ESCC) after minimally invasive esophagectomy (MIE). METHODS: The study involved a retrospective analysis of 613 ESCC patients, from the prospectively maintained database from January 2011 to December 2018. All the included ESCC patients underwent MIE, and they were randomly (1:1) assigned to the training cohort (307 patients) and the validation cohort (306 patients). Kaplan-Meier survival analysis was used to analyze the differences recorded between overall survival (OS) and disease-free survival (DFS). In the case of the training cohort, the nomograms based on non-TO were developed using Cox regression, and the performance of these nomograms was calibrated and evaluated in the validation cohort. RESULTS: Significant differences were recorded for 5-year OS and DFS between non-TO and TO groups (p < 0.05). Multivariate cox analysis revealed that non-TO, intraoperative bleeding, T stage, and N stage acted as independent risk factors that affected OS and DFS (p < 0.05). The results for multivariate regression were used to build non-TO-based nomograms to predict OS and DFS of patients with ESCC, the t-AUC curve analysis showed that the nomograms predicting OS and DFS were more accurate as compared to TNM staging, during the follow-up period in the training cohort and validation cohort. Further, the nomogram score was used to divide ESCC patients into low-, middle-, and high-risk groups and significant differences were recorded for OS and DFS between these three groups (p < 0.001). CONCLUSIONS: Non-TO was identified as an independent prognostic factor for ESCC patients. The nomograms based on non-TO could availably predict OS and DFS in ESCC patients after MIE.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Esofagectomia/métodos , Nomogramas , Carcinoma de Células Escamosas/patologia , Estudos Retrospectivos , Neoplasias Esofágicas/patologia , Prognóstico , Estadiamento de Neoplasias , Células Epiteliais/patologia
16.
Angew Chem Int Ed Engl ; 61(51): e202212164, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36240785

RESUMO

The production of conjugated C4-C5 dienes from biomass can enable the sustainable synthesis of many important polymers and liquid fuels. Here, we report the first example of bimetallic (Nb, Al)-atomically doped mesoporous silica, denoted as AlNb-MCM-41, which affords quantitative conversion of 2-methyltetrahydrofuran (2-MTHF) to pentadienes with a high selectivity of 91 %. The incorporation of AlIII and NbV sites into the framework of AlNb-MCM-41 has effectively tuned the nature and distribution of Lewis and Brønsted acid sites within the structure. Operando X-ray absorption, diffuse reflectance infrared and solid-state NMR spectroscopy collectively reveal the molecular mechanism of the conversion of adsorbed 2-MTHF over AlNb-MCM-41. Specifically, the atomically-dispersed NbV sites play an important role in binding 2-MTHF to drive the conversion. Overall, this study highlights the potential of hetero-atomic mesoporous solids for the manufacture of renewable materials.


Assuntos
Alcadienos , Nióbio , Nióbio/química , Alumínio , Catálise
17.
J Am Chem Soc ; 143(29): 10977-10985, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34279096

RESUMO

Metal-organic framework (MOF) materials provide an excellent platform to fabricate single-atom catalysts due to their structural diversity, intrinsic porosity, and designable functionality. However, the unambiguous identification of atomically dispersed metal sites and the elucidation of their role in catalysis are challenging due to limited methods of characterization and lack of direct structural information. Here, we report a comprehensive investigation of the structure and the role of atomically dispersed copper sites in UiO-66 for the catalytic reduction of NO2 at ambient temperature. The atomic dispersion of copper sites on UiO-66 is confirmed by high-angle annular dark-field scanning transmission electron microscopy, electron paramagnetic resonance spectroscopy, and inelastic neutron scattering, and their location is identified by neutron powder diffraction and solid-state nuclear magnetic resonance spectroscopy. The Cu/UiO-66 catalyst exhibits superior catalytic performance for the reduction of NO2 at 25 °C without the use of reductants. A selectivity of 88% for the formation of N2 at a 97% conversion of NO2 with a lifetime of >50 h and an unprecedented turnover frequency of 6.1 h-1 is achieved under nonthermal plasma activation. In situ and operando infrared, solid-state NMR, and EPR spectroscopy reveal the critical role of copper sites in the adsorption and activation of NO2 molecules, with the formation of {Cu(I)···NO} and {Cu···NO2} adducts promoting the conversion of NO2 to N2. This study will inspire the further design and study of new efficient single-atom catalysts for NO2 abatement via detailed unravelling of their role in catalysis.

18.
BMC Cancer ; 21(1): 1170, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34724907

RESUMO

BACKGROUND: The prognosis of patients with gastrointestinal stromal tumors (GISTs) is generally evaluated at the time of diagnosis but does not reflect the survival dynamics of patients in the future. Therefore, the purpose of this article was to evaluate the conditional survival (CS) of Chinese patients with GISTs after radical resection. METHODS: This retrospective study included 451 patients who underwent radical surgery for GISTs. A Cox proportional hazard model was used to evaluate the prognostic factors of disease-free survival (DFS). The 3-year conditional DFS (CDFS3) of patients who survived for x years was expressed as CDFS3=DFS(x + 3)/DFS(x). RESULTS: The traditional 3-year DFS rate decreased gradually from 94.0% at 3 years to 77.3% at 7 years, while the CDFS3 rate increased from 94.0 to 95.2% over the survival time of the patients. In addition, classic clinicopathological prognostic factors had different effects on CDFS3, with changes observed in survival time, but these effects were only slight or moderate (|d|<0.5). Although multivariate analysis showed that age, sex, mitotic index and tumor rupture were independent risk factors for DFS at baseline, all adverse prognostic factors, except for the mitotic index, lost their predictive significance at 5 years after operation. When the Modified NIH criteria were included, the risk staging was found to be an independent risk factor for recurrence or death. Time-dependent Cox regression analysis showed that the modified NIH criteria independently affected the recurrence or death of GIST patients within 2 years after operation. CONCLUSION: CS provides detailed dynamic survival information about Chinese patients with primary resected GISTs. The mitotic index is of great clinical significance for the monitoring and follow-up of patient populations with a high risk of tumor recurrence or death until 5 years after surgery.


Assuntos
Tumores do Estroma Gastrointestinal/mortalidade , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Intervalo Livre de Doença , Feminino , Seguimentos , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Índice Mitótico , Análise Multivariada , Recidiva Local de Neoplasia/mortalidade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores Sexuais , Fatores de Tempo , Carga Tumoral , Adulto Jovem
19.
BMC Psychiatry ; 21(1): 521, 2021 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-34674680

RESUMO

BACKGROUND: Previous studies have shown a positive association between sleep deprivation and non-suicidal self-injury (NSSI) among adolescents, but few studies have described the effects of oversleeping and weekend catch-up sleep on NSSI. The present study aimed to explore the nonlinear relationship between sleep duration and NSSI among Chinese adolescents. METHODS: Data from China's National Adolescent Health Surveillance for the years 2014 to 2015 were collected from 15,713 students located across four provinces in China. A self-report questionnaire was used to assess sleep duration and 12-month NSSI. Binomial logistic regression models were used to examine the association between NSSI and sleep duration. The locally estimated scatter plot smoothing (LOESS) method was used to explore the associations of total NSSI number with sleep duration, and binomial regression analysis was used to test this relationship. RESULTS: About 68.5% of adolescents reported sleeping less than 8 h on weeknights, while 37.8% of adolescents slept more than 10 h per night during weekends. The 12-month prevalence rate of NSSI was 29.4%. Compared to adolescents who reported weekend catch-up sleep of 0-1 h, those who slept < 0 h (adjusted odds ratio [aOR] = 1.38, 95% Confidence Interval [95% CI]: 1.16-1.64) had a higher risk of NSSI. Males who reported ≥3 h of weekend catch-up sleep had significantly increased odds of NSSI (aOR = 1.20, 95%CI: 1.01-1.42). Notably, a positive U-shaped association was observed between the sleep duration and the total NSSI number. CONCLUSIONS: The findings reveal a nonlinear relationship between sleep duration and NSSI among Chinese adolescents. Therefore, it is necessary to be vigilant and screen for sleep duration among adolescents in NSSI treatment or prevention.


Assuntos
Comportamento Autodestrutivo , Adolescente , China/epidemiologia , Humanos , Masculino , Fatores de Risco , Comportamento Autodestrutivo/epidemiologia , Sono , Estudantes
20.
Angew Chem Int Ed Engl ; 60(28): 15541-15547, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-33826198

RESUMO

Industrial purification of propylene and ethylene requires cryogenic distillation and selective hydrogenation over palladium catalysts to remove propane, ethane and/or trace amounts of acetylene. Here, we report the excellent separation of equimolar mixtures of propylene/propane and ethylene/ethane, and of a 1/100 mixture of acetylene/ethylene by a highly robust microporous material, MFM-520, under dynamic conditions. In situ synchrotron single crystal X-ray diffraction, inelastic neutron scattering and analysis of adsorption thermodynamic parameters reveal that a series of synergistic host-guest interactions involving hydrogen bonding and π⋅⋅⋅π stacking interactions underpin the cooperative binding of alkenes within the pore. Notably, the optimal pore geometry of the material enables selective accommodation of acetylene. The practical potential of this porous material has been demonstrated by fabricating mixed-matrix membranes comprising MFM-520, Matrimid and PIM-1, and these exhibit not only a high permeability for propylene (≈1984 Barrer), but also a separation factor of 7.8 for an equimolar mixture of propylene/propane at 298 K.

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