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1.
Proc Natl Acad Sci U S A ; 121(14): e2319288121, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38527206

RESUMEN

Design tactics and mechanistic studies both remain as fundamental challenges during the exploitations of earth-abundant molecular electrocatalysts for CO2 reduction, especially for the rarely studied Cr-based ones. Herein, a quaterpyridyl CrIII catalyst is found to be highly active for CO2 electroreduction to CO with 99.8% Faradaic efficiency in DMF/phenol medium. A nearly one order of magnitude higher turnover frequency (86.6 s-1) over the documented Cr-based catalysts (<10 s-1) can be achieved at an applied overpotential of only 190 mV which is generally 300 mV lower than these precedents. Such a high performance at this low driving force originates from the metal-ligand cooperativity that stabilizes the low-valent intermediates and serves as an efficient electron reservoir. Moreover, a synergy of electrochemistry, spectroelectrochemistry, electron paramagnetic resonance, and quantum chemical calculations allows to characterize the key CrII, CrI, Cr0, and CO-bound Cr0 intermediates as well as to verify the catalytic mechanism.

2.
J Chem Phys ; 159(2)2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37428052

RESUMEN

Excited states are the key species in photocatalysis, while the critical parameters that govern their applications are (i) excitation energy, (ii) accessibility, and (iii) lifetime. However, in molecular transition metal-based photosensitizers, there is a design tension between the creation of long-lived excited (triplet), e.g., metal-to-ligand charge transfer (3MLCT) states and the population of such states. Long-lived triplet states have low spin-orbit coupling (SOC) and hence their population is low. Thus, a long-lived triplet state can be populated but inefficiently. If the SOC is increased, the triplet state population efficiency is improved-coming at the cost of decreasing the lifetime. A promising strategy to isolate the triplet excited state away from the metal after intersystem crossing (ISC) involves the combination of transition metal complex and an organic donor/acceptor group. Here, we elucidate the excited state branching processes in a series of Ru(II)-terpyridyl push-pull triads by quantum chemical simulations. Scalar-relativistic time-dependent density theory simulations reveal that efficient ISC takes place along 1/3MLCT gateway states. Subsequently, competitive electron transfer (ET) pathways involving the organic chromophore, i.e., 10-methylphenothiazinyl and the terpyridyl ligands are available. The kinetics of the underlying ET processes were investigated within the semiclassical Marcus picture and along efficient internal reaction coordinates that connect the respective photoredox intermediates. The key parameter that governs the population transfer away from the metal toward the organic chromophore either by means of ligand-to-ligand (3LLCT; weakly coupled) or intra-ligand charge transfer (3ILCT; strongly coupled) states was determined to be the magnitude of the involved electronic coupling.

3.
World J Surg Oncol ; 21(1): 137, 2023 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-37101165

RESUMEN

BACKGROUND & AIMS: In this retrospective study, we aimed to elucidate how the initial recurrence site influences the post-recurrence survival (PRS) after the curative resection of colorectal cancer. PATIENTS AND METHODS: We collected samples from patients with stage I-III colorectal adenocarcinoma who were admitted to Yunnan Cancer Hospital from January 2008 to December 2019. Four hundred and six patients who developed recurrence after radical resection were included. The cases were classified according to the original site of recurrence as follows: liver metastases (n = 98), lung metastases (n = 127), peritoneum (n = 32), other individual organ (n = 69), two or more organs or sites (n = 49), and local recurrence (n = 31). Kaplan-Meier survival curves were used to compare the PRS of patients with different initial sites of recurrence. The influence of the initial recurrence site on PRS was analyzed using the Cox proportional hazards model. RESULTS: The 3-year PRS of simple liver metastasis was 54.04% (95% CI, 45.46%-64.24%), and the 3-year PRS of simple lung metastasis was 50.05% (95% CI, 42.50%-58.95%). No significant difference was observed between simple liver metastasis or simple lung metastasis and local recurrence with a 3-year PRS of 66.99% (95% CI, 53.23%-84.32%). The 3-year PRS for peritoneal metastases was 25.43% (95% CI, 14.76%-43.82%), and the 3-year PRS for two or more organ sites was 34.84% (95% CI, 24.16%-50.24%). The peritoneal (hazard ratio [HR], 1.75; 95% CI, 1.10-2.79; P = 0.0189) and metastasis to two or more organs or sites (HR, 1.59; 95% CI, 1.05-2.43; P = 0.0304) were PRS-independent adverse prognostic factors. CONCLUSION: The prognosis of patients with peritoneum and multiple organs or sites recurred was poor. This study suggests early monitoring of peritoneal and multiple organ or site recurrence after surgery. This part of patients should receive comprehensive treatment as early as possible to improve their prognosis.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Hepáticas , Neoplasias Pulmonares , Humanos , Estudios Retrospectivos , Recurrencia Local de Neoplasia/patología , China , Pronóstico , Neoplasias Pulmonares/patología , Neoplasias Colorrectales/patología , Neoplasias Hepáticas/cirugía
4.
J Org Chem ; 81(20): 10056-10061, 2016 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-27668675

RESUMEN

An asymmetric Friedel-Crafts alkylation reaction of 2-furfuryl ketones with ß-trifluoromethyl enones has been developed via formal trienamine catalysis of a bifunctional primary amine-thiourea substance derived from L-tert-leucine, delivering the furan derivatives incorporating a stereogenic trifluoromethyl (CF3) group in good to high yields with excellent enantioselectivity.

5.
J Breast Cancer ; 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39069782

RESUMEN

PURPOSE: The interval between neoadjuvant chemotherapy (NAC) and surgery for locally advanced breast cancer (LABC) remains controversial. At the same time, the prognostic effect of delayed surgery in patients with poor responses is currently unclear. METHODS: Data was collected from patients who had poor responses to NAC and underwent modified radical surgery from January 2013 to December 2018. The interval from completion of NAC to surgery was divided into two groups: a longer (greater than four weeks) or shorter (four weeks or less) interval. The associations of these interval groups with overall survival (OS) and recurrence-free survival (RFS) were evaluated by multivariable Cox models adjusting for the existing prognostic factors. Propensity score matching (PSM) was used to minimize election bias. RESULTS: A total of 1,229 patients (mean age, 47.2 ± 8.9 years; median follow-up duration, 32.67 [6.57-52.63] months) were included. The 5-year OS rates were 73.2% and 60.8% in the shorter (n = 171) and longer interval group (n = 1,058), respectively, while the 3-year RFS rates were 80.8% and 71.7%, respectively. In multivariate Cox analysis, the longer interval was associated with an increased risk of mortality (hazard ratio [HR], 1.43; 95% confidence interval [CI], 1.01-2.02; p = 0.046) and recurrence (HR, 1.50; 95% CI, 1.12-1.99; p = 0.006). There was an interaction between the molecular subtype and the surgery interval for OS (pinteraction = 0.014) and RFS (pinteraction = 0.027). After PSM, no significant difference in OS (p = 0.180) and RFS (p = 0.069) was observed between the two groups. CONCLUSION: Among LABC patients with a poor response, those with a longer interval between NAC and surgery had worse OS and RFS. The results indicate that these patients should receive modified radical surgery timely, which may in turn improve their prognosis.

6.
ChemistryOpen ; 13(5): e202300183, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38595069

RESUMEN

We present a luminescent Ir(III) complex featuring a bidentate halogen bond donor site capable of strong anion binding. The tailor-made Ir(III)(L)2 moiety offers a significantly higher emission quantum yield (8.4 %) compared to previous Ir(III)-based chemo-sensors (2.5 %). The successful binding of chloride, bromide and acetate is demonstrated using emission titrations. These experiments reveal association constants of up to 1.6×105 M-1. Furthermore, a new approach to evaluate the association constant by utilizing the shift of the emission was used for the first time. The experimentally observed characteristics are supported by quantum chemical simulations.

7.
J Gastrointest Surg ; 28(5): 710-718, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38462423

RESUMEN

BACKGROUND: Liver metastasis (LIM) is an important factor in the diagnosis, treatment, follow-up, and prognosis of patients with gastric gastrointestinal stromal tumor (GIST). There is no simple tool to assess the risk of LIM in patients with gastric GIST. Our aim was to develop and validate a nomogram to identify patients with gastric GIST at high risk of LIM. METHODS: Patient data diagnosed as having gastric GIST between 2010 and 2019 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database and randomly divided into training cohort and internal validation cohort in a 7:3 ratio. For external validation, retrospective data collection was performed on patients diagnosed as having gastric GIST at Yunnan Cancer Center (YNCC) between January 2015 and May 2023. Univariate and multivariate logistic regression analyses were used to identify independent risk factors associated with LIM in patients with gastric GIST. An individualized LIM nomogram specific for gastric GIST was formulated based on the multivariate logistic model; its discriminative performance, calibration, and clinical utility were evaluated. RESULTS: In the SEER database, a cohort of 2341 patients with gastric GIST was analyzed, of which 173 cases (7.39%) were found to have LIM; 239 patients with gastric GIST from the YNCC database were included, of which 25 (10.46%) had LIM. Multivariate analysis showed tumor size, tumor site, and sex were independent risk factors for LIM (P < .05). The nomogram based on the basic clinical characteristics of tumor size, tumor site, sex, and age demonstrated significant discrimination, with an area under the curve of 0.753 (95% CI, 0.692-0.814) and 0.836 (95% CI, 0.743-0.930) in the internal and external validation cohort, respectively. The Hosmer-Lemeshow test showed that the nomogram was well calibrated, whereas the decision curve analysis and the clinical impact plot demonstrated its clinical utility. CONCLUSION: Tumor size, tumor subsite, and sex were significantly correlated with the risk of LIM in gastric GIST. The nomogram for patients with GIST can effectively predict the individualized risk of LIM and contribute to the planning and decision making related to metastasis management in clinical practice.


Asunto(s)
Tumores del Estroma Gastrointestinal , Neoplasias Hepáticas , Nomogramas , Neoplasias Gástricas , Humanos , Tumores del Estroma Gastrointestinal/patología , Tumores del Estroma Gastrointestinal/secundario , Masculino , Femenino , Persona de Mediana Edad , Neoplasias Hepáticas/secundario , Neoplasias Gástricas/patología , Estudios Retrospectivos , Anciano , Factores de Riesgo , Programa de VERF , Adulto , Medición de Riesgo , Pronóstico , Modelos Logísticos
8.
Ann Nucl Med ; 38(7): 534-543, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38602614

RESUMEN

OBJECTIVE: To investigate the survival benefit of preoperative bone scan in asymptomatic patients with early-stage non-small cell lung cancer (NSCLC). METHODS: This retrospective study included patients with radical resection for stage T1N0M0 NSCLC between March 2013 and December 2018. During postoperative follow-up, we monitored patient survival and the development of bone metastasis. We compared overall survival, bone metastasis-free survival, and recurrence-free survival in patients with or without preoperative bone scan. Propensity score matching and inverse probability of treatment weighting were used to minimize election bias. RESULTS: A total of 868 patients (58.19 ± 9.69 years; 415 men) were included in the study. Of 87.7% (761 of 868) underwent preoperative bone scan. In the multivariable analyses, bone scan did not improve overall survival (hazard ratio [HR] 1.49; 95% confidence intervals [CI] 0.91-2.42; p = 0.113), bone metastasis-free survival (HR 1.18; 95% CI 0.73-1.90; p = 0.551), and recurrence-free survival (HR 0.89; 95% CI 0.58-1.39; p = 0.618). Similar results were obtained after propensity score matching (overall survival [HR 1.28; 95% CI 0.74-2.23; p = 0.379], bone metastasis-free survival [HR 1.00; 95% CI 0.58-1.72; p = 0.997], and recurrence-free survival [HR 0.76; 95% CI 0.46-1.24; p = 0.270]) and inverse probability of treatment weighting. CONCLUSION: There were no significant differences in overall survival, bone metastasis-free survival, and recurrence-free survival between asymptomatic patients with clinical stage IA NSCLC with or without preoperative bone scan.


Asunto(s)
Neoplasias Óseas , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Estadificación de Neoplasias , Humanos , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Masculino , Femenino , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Persona de Mediana Edad , Estudios Retrospectivos , Neoplasias Óseas/secundario , Neoplasias Óseas/diagnóstico por imagen , Pronóstico , Anciano , Huesos/diagnóstico por imagen , Huesos/patología
9.
Anim Biosci ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38938039

RESUMEN

Objective: The liver plays a dual role in regulating temperature and immune responses. Examining the influence of Heat stress (HS) on liver T cells contributes significantly to understanding the intricate interplay between the immune system and hepatic tissues under thermal stress. This study focused on investigating the characteristics of the T-cell receptor (TCR) ß chain CDR3 repertoire in bovine liver samples under both HS and pair-fed (PF) environmental conditions. Methods: Sequencing data from six samples sourced from the GEO database underwent annotation. Utilizing immunarch and VDJtool software, the study conducted comprehensive analyses encompassing basic evaluation, clonality assessment, immune repertoire comparison, diversity estimation, gene usage profiling, VJ gene segment pairing scrutiny, clonal tracking, and Kmers analysis. Results: All four TCR chains, namely α, ß, γ, and δ, were detected, with the α chains exhibiting the highest detection frequency, followed closely by the ß chains. The prevalence of αß TCRs in bovine liver samples underscored their crucial role in governing hepatic tissue's physiological functions. The TCR ß CDR3 repertoire showcased substantial inter-individual variability, featuring diverse clonotypes exhibiting distinct amino acid lengths. Intriguingly, HS cattle displayed heightened diversity and clonality, suggesting potential peripheral T cell migration into the liver under environmental conditions. Notably, differential VJ gene pairings were observed in HS cattle compared to the PF, despite individual variations in V and J gene utilization. Additionally, while most high-frequency amino acid 5-mers remained consistent between the HS and PF, GELHF and YDYHF were notably prevalent in the HS group. Across all samples, a prevalent trend of high-frequency 5mers skewed towards polar and hydrophobic amino acids was evident. Conclusion: This study elucidates the characteristics of liver TCR ß chain CDR3 repertoire under HS conditions, enhancing our understanding of HS implications.

10.
Cancer Imaging ; 23(1): 116, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38041154

RESUMEN

BACKGROUND: The correlation between the preoperative splenic area measured on CT scans and the overall survival (OS) of early-stage non-small cell lung cancer (NSCLC) patients remains unclear. METHODS: A retrospective discovery cohort and validation cohort consisting of consecutive NSCLC patients who underwent resection and preoperative CT scans were created. The patients were divided into two groups based on the measurement of their preoperative splenic area: normal and abnormal. The Cox proportional hazard model was used to analyse the correlation between splenic area and OS. RESULTS: The discovery and validation cohorts included 2532 patients (1374 (54.27%) males; median (IQR) age 59 (52-66) years) and 608 patients (403 (66.28%) males; age 69 (62-76) years), respectively. Patients with a normal splenic area had a 6% higher 5-year OS (n = 727 (80%)) than patients with an abnormal splenic area (n = 1805 (74%)) (p = 0.007) in the discovery cohort. A similar result was obtained in the validation cohort. In the univariable analysis, the OS hazard ratios (HRs) for the patients with abnormal splenic areas were 1.32 (95% confidence interval (CI): 1.08, 1.61) in the discovery cohort and 1.59 (95% CI: 1.01, 2.50) in the validation cohort. Multivariable analysis demonstrated that abnormal splenic area was independent of shorter OS in the discovery (HR: 1.32, 95% CI: 1.08, 1.63) and validation cohorts (HR: 1.84, 95% CI: 1.12, 3.02). CONCLUSION: Preoperative CT measurements of the splenic area serve as a prognostic indicator for early-stage NSCLC patients, offering a novel metric with potential implications for personalized therapeutic strategies in top-tier oncology research.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células Pequeñas , Masculino , Humanos , Persona de Mediana Edad , Anciano , Femenino , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Pronóstico , Estudios Retrospectivos , Estadificación de Neoplasias , Biomarcadores
11.
Oncotarget ; 13: 641, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35548328

RESUMEN

[This corrects the article DOI: 10.18632/oncotarget.22600.].

12.
Environ Technol ; 43(11): 1613-1623, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33135954

RESUMEN

Lead-zinc tailings are generated during the mining process which is considered as hazardous solid waste due to its high heavy metal content and leachability in the natural state. At present, the most effective technology for disposing heavy metals in solid wastes is the solidification/stabilization (S/S) technique. In terms of S/S technology, chemical stabilization is one of the most potential and practical method. This paper aims to investigate the S/S property of four typical chemical agents (Na2S, NaH2PO4, TMT and Na2EDTA) on the heavy metals in lead-zinc tailings. The results reveal that the heavy metals lead and zinc in tailings are stabilized more effectively by using chelating agents TMT than by using inorganic chemical agents Na2S and NaH2PO4. When the dosage of TMT reaches 4%, the leaching concentration of lead and zinc is 0.18 and 14.60 mg/L according to toxicity characteristic leaching procedure (TCLP), and the stabilization efficiency of lead and zinc is 99.31% and 80.92%, respectively, while the leaching concentration of lead and zinc just drops to 0.41 and 16.00 mg/L with addition of 10% NaH2PO4. Furthermore, the leaching concentration of heavy metal lead in tailings treated by 4% Na2EDTA increases to 53.44 mg/L which far exceeds the standard of pollution control. Therefore, considering stabilization efficiency and dosage, TMT is the preferred agent for solidifying heavy metals in lead-zinc tailings.


Asunto(s)
Metales Pesados , Zinc , Ácido Edético , Plomo , Metales Pesados/análisis , Residuos Sólidos , Zinc/análisis
13.
JACS Au ; 2(6): 1359-1374, 2022 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-35783182

RESUMEN

The sunlight-driven reduction of CO2 into carbonaceous fuels can lower the atmospheric CO2 concentration and provide renewable energy simultaneously, attracting scientists to design photocatalytic systems for facilitating this process. Significant progress has been made in designing high-performance photosensitizers and catalysts in this regard, and further improvement can be realized by installing additional interactions between the abovementioned two components, however, the design strategies and mechanistic investigations on such interactions remain challenging. Here, we present the construction of molecular models for intermolecular π-π interactions between the photosensitizer and the catalyst, via the introduction of pyrene groups into both molecular components. The presence, types, and strengths of diverse π-π interactions, as well as their roles in the photocatalytic mechanism, have been examined by 1H NMR titration, fluorescence quenching measurements, transient absorption spectroscopy, and quantum chemical simulations. We have also explored the rare dual emission behavior of the pyrene-appended iridium photosensitizer, of which the excited state can deliver the photo-excited electron to the pyrene-decorated cobalt catalyst at a fast rate of 2.60 × 106 s-1 via co-facial π-π interaction, enabling a remarkable apparent quantum efficiency of 14.3 ± 0.8% at 425 nm and a high selectivity of 98% for the photocatalytic CO2-to-CO conversion. This research demonstrates non-covalent interaction construction as an effective strategy to achieve rapid CO2 photoreduction besides a conventional photosensitizer/catalyst design.

14.
Eur J Radiol ; 151: 110309, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35468444

RESUMEN

PURPOSE: Intra-tumoral tertiary lymphoid structures (TLSs) are associated with a favorable prognosis for patients with hepatocellular carcinoma (HCC). We aimed to identify image features related to TLSs and develop a nomogram for preoperative noninvasive prediction of intra-tumoral TLSs. METHODS: This retrospective study enrolled patients with HCC who underwent contrast-enhanced computed tomography before surgery between January 2014 and September 2020. Two radiologists retrospectively and independently reviewed the CT imaging features, and interobserver agreement was assessed. Univariable and multivariable logistic regression analyses were applied to investigate clinical laboratory data and imaging features related to TLSs. A regression-based predictive model and nomogram were constructed using the identified predictors. Nomogram diagnostic performance was assessed with the area under the receiver operating characteristic curve (AUC) and calibration curves, and validated using 5-fold cross-validation. RESULTS: Ninety-three of the 142 HCCs were TLS + HCCs. Multivariable analyses identified intratumor arteries (odds ratio [OR]: 0.23; 95% confidence interval [CI]: 0.07-0.63; p = 0.007), intratumor hemorrhage (OR: 0.08; 95% CI: 0.01-0.50; p = 0.012), positive HBsAg or HCVAB status (OR: 4.52; 95% CI: 1.65-13.29; p = 0.004), platelet count (≥186.5 × 109 /L, OR: 0.38; 95% CI: 0.16-0.86; p = 0.022), and aspartate transaminase level (≥33.2 IU/l, OR: 0.24; 95% CI: 0.09-0.59; p = 0.003) as independent predictors of intra-tumoral TLSs. AUC of the regression-based model was 0.79 (95% CI:0.72-0.86) and average AUC at 5-fold cross-validation was 0.75 (95% CI: 0.71-0.80). CONCLUSIONS: CT-based nomogram is promising for preoperative prediction of intra-tumoral TLS in HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Estructuras Linfoides Terciarias , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos
15.
Front Oncol ; 12: 1015011, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36330467

RESUMEN

Purpose: To explore the relationship between blood-brain barrier (BBB) leakage and brain structure in non-brain metastasis lung cancer (LC) by magnetic resonance imaging (MRI) as well as to indicate the possibility of brain metastasis (BM) occurrence. Patients and methods: MRI were performed in 75 LC patients and 29 counterpart healthy peoples (HCs). We used the Patlak pharmacokinetic model to calculate the average leakage in each brain region according to the automated anatomical labeling (AAL) atlas. The thickness of the cortex and the volumes of subcortical structures were calculated using the FreeSurfer base on Destrieux atlas. We compared the thickness of the cerebral cortex, the volumes of subcortical structures, and the leakage rates of BBB, and evaluated the relationships between these parameters. Results: Compared with HCs, the leakage rates of seven brain regions were higher in patients with advanced LC (aLC). In contrast to patients with early LC (eLC), the cortical thickness of two regions was decreased in aLCs. The volumes of twelve regions were also reduced in aLCs. Brain regions with increased BBB penetration showed negative correlations with thinner cortices and reduced subcortical structure volumes (P<0.05, R=-0.2 to -0.50). BBB penetration was positively correlated with tumor size and with levels of the tumor marker CYFRA21-1 (P<0.05, R=0.2-0.70). Conclusion: We found an increase in BBB permeability in non-BM aLCs that corresponded to a thinner cortical thickness and smaller subcortical structure volumes. With progression in LC staging, BBB shows higher permeability and may be more likely to develop into BM.

16.
Front Oncol ; 11: 770758, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35070974

RESUMEN

BACKGROUND: Sensitivity to neoadjuvant chemotherapy in locally advanced gastric cancer patients varies; however, an effective predictive marker is currently lacking. We aimed to propose and validate a practical treatment efficacy prediction method based on contrast-enhanced computed tomography (CECT) radiomics. METHOD: Data of l24 locally advanced gastric carcinoma patients who underwent neoadjuvant chemotherapy were acquired retrospectively between December 2012 and August 2020 from three different cancer centers. In total, 1216 radiomics features were initially extracted from each lesion's pretreatment portal venous phase computed tomography image. Subsequently, a radiomics predictive model was constructed using machine learning software. Clinicopathological data and radiological parameters of the enrolled patients were collected and analyzed retrospectively. Univariate and multivariate logistic regression analyses were performed to screen for independent predictive indices. Finally, we developed an integrated model combining clinicopathological predictive parameters and radiomics features. RESULT: In the training set, 10 (14.9%) patients achieved a good response (GR) after preoperative neoadjuvant chemotherapy (n = 77), whereas in the testing set, seven (17.5%) patients achieved a GR (n = 47). The radiomics predictive model showed competitive prediction efficacy in both the training and independent external validation sets. The areas under the curve (AUC) values were 0.827 (95% confidence interval [CI]: 0.609-1.000) and 0.854 (95% CI: 0.610-1.000), respectively. Similarly, when only the single hospital data were included as an independent external validation set (testing set 2), AUC values of the models were 0.827 (95% CI: 0.650-0.952) and 0.889 (95% CI: 0.663-1.000) in the training set and testing set 2, respectively. CONCLUSION: Our study is the first to discover that CECT radiomics could provide powerful and consistent predictions of therapeutic sensitivity to neoadjuvant chemotherapy among gastric cancer patients across different hospitals.

17.
Oncotarget ; 9(15): 11964-11976, 2018 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-29552285

RESUMEN

The beginning and the end of the vascular normalization window are not clear in response to anti-angiogenic therapies. We used dynamic contrast-enhanced MRI (DCE-MRI) and intravoxel incoherent motion MRI (IVIM-MRI) to noninvasively evaluate the vascular normalization window. MRI was performed five times: before treatment and on the second, fourth, sixth and eighth days of treatment. Quantitative perfusion parameters were calculated at each time point, including the volume transfer coefficient (Ktrans), reverse transfer constant (Kep), pseudodiffusion coefficient (D*) and perfusion fraction (f). Tumors were evaluated for changes by immunohistochemistry. An increase in Ktrans and Kep was observed after bevacizumab treatment on days 2 and 4. Similar trends were observed for D* and f on days 2 and 4. However, the parameters of Ktrans, Kep, D* and f were decreased on days 6 and 8. A significant increase of the vessel maturity index between the treatment and control groups was measured on days 2 and 4, but this increase abated by days 6 and 8. IVIM and DCE-MRI are helpful when quantifying the tumor perfusion and evaluating the vascular normalization window after anti-vessel therapy. IVIM and DCE-MRI can outline the important period after anti-vessel treatment.

18.
J Hazard Mater ; 142(1-2): 431-6, 2007 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-17030424

RESUMEN

Hexachlorobenzene removal efficiencies in different solvents by electron beam irradiation were investigated. Several factors that might affect the removal efficiencies were further examined. At 10 kGy, HCB degradation value was 85.8% in the solvent of acetone:water mixture (20:80, v/v), while at the same dose, the reduction value of 42.6% was achieved in hexane solvent. In the solvent of acetone:water mixture (20:80, v/v), Na(2)CO(3) as additive could enhance the degradation efficiency by 4.5%. However, Triton X-100, NaNO(3), NaNO(2) and H(2)O(2) as additives reduced the degradation value by 20.0%, 6.3%, 85.7% and 20.5%, respectively. Furthermore, the increase of these additives would result in the decrease of the degradation efficiencies. The pH value of the solvent of acetone:water mixture (20:80, v/v) could affect HCB removal efficiency. At pH 11.8, reduction value of 90.2% was achieved at 10 kGy, while at the same dose, at pH 2.7 and 6.8, the reduction values were only 82.4% and 86.9%, respectively. At the same time, the degradation value of pentachlorobenzene was 94.7% at 10 kGy. In the presence or absence of additives, pH value of the solvent of acetone:water mixture (20:80, v/v) became lower with increasing dose after electron beam irradiation.


Asunto(s)
Electrones , Hexaclorobenceno/química , Contaminantes Ambientales , Concentración de Iones de Hidrógeno
19.
Onco Targets Ther ; 10: 2297-2303, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28490887

RESUMEN

OBJECTIVES: Most colorectal cancers are classical adenocarcinomas (AC), and less frequent subtypes include mucinous adenocarcinomas (MAC) and signet-ring cell carcinomas (SC). The purpose of this study was to evaluate the computed tomography (CT) findings that can help to differentiate MAC and SC from AC. METHODS: CT scans of 168 patients with pathologically proven MAC and 67 patients with pathologically proven SC were analyzed, and 220 patients with classical AC were also included as a control group. CT findings of the three groups were compared and contrasted in terms of the bowel involvement patterns, contrast enhancement patterns, and presence or absence of bowel obstruction, intratumoral calcification, pericolic fat infiltration, and local tumor extension to adjacent organs. Statistical analyses were made by using the one-way analysis of variance, least significant difference test, and Pearson's chi-square test. RESULTS: Compared with classical AC, the MAC showed more severe (6.29±2.69 cm vs 4.57±1.74 cm, P<0.001) and higher percentage of occurrence of eccentric bowel-wall thickening (37.2% vs 11.5%, P<0.001). Heterogeneous contrast enhancement was most common in MAC (P<0.01), and MAC showed more areas with hypoattenuation (P<0.001). The presence of intratumoral calcification was most frequent in MAC (17.9% vs 2% vs 6.8%) (P<0.001); the SC also were more severe (5.75±2.28 cm vs 4.57±1.74 cm. P=0.001) than AC, but SC tend to show more cases of concentric even bowel-wall thickening (67.2%); homogeneous contrast enhancement was most common in SC (P<0.01), and it showed a target appearance. The presence of peritoneal seeding was most frequent in SC (35.8% vs 8% vs 2.7%, P<0.001), while the presence of regional lymph node metastasis (P=0.190) and direct invasion of adjacent organs or metastasis (P=0.323) were not significantly different among them. CONCLUSION: Some radiological features by CT can be used to classify different colon tumor types.

20.
Onco Targets Ther ; 9: 1599-603, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27073324

RESUMEN

Ewing's sarcoma/primary neuroectodermal tumor (EWS/PNET) is an extraordinarily rare primary tumor of the kidney with characteristic histology. To date, the imaging features of EWS/PNET have not been clearly described. Here, we report two cases of EWS/PNET confirmed by fine-needle aspiration biopsy and analyze the findings of computed tomography and ultrasound. The radiological features of EWS/PNET are presented along with a brief review of the pertinent literature to have a further understanding of EWS/PNET's imaging features.

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