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1.
Nano Lett ; 24(37): 11599-11606, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39229905

RESUMO

2D layered metal halide perovskites (MHPs) are a potential material for fabricating self-powered photodetectors (PDs). Nevertheless, 2D MHPs produced via solution techniques frequently exhibit multiple quantum wells, leading to notable degradation in the device performance. Besides, the wide band gap in 2D perovskites limits their potential for broad-band photodetection. Integrating narrow-band gap materials with perovskite matrices is a viable strategy for broad-band PDs. In this study, the use of methylamine acetate (MAAc) as an additive in 2D perovskite precursors can effectively control the width of the quantum wells (QWs). The amount of MAAc greatly affects the phase purity. Subsequently, PbSe QDs were embedded into the 2D perovskite matrix with a broadened absorption spectrum and no negative effects on ferroelectric properties. PM6:Y6 was combined with the hybrid ferroelectric perovskite films to create a self-powered and broad-band PD with enhanced performance due to a ferro-pyro-phototronic effect, reaching a peak responsivity of 2.4 A W-1 at 940 nm.

2.
Anal Chem ; 96(14): 5640-5647, 2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38551637

RESUMO

Detection and discrimination of fluoroquinolones (FQs) are crucial for food safety but remain a formidable challenge due to their minor differences in molecular structures and the serious interferences from food matrices. Herein, we propose an afterglow assay for the detection and discrimination of FQs through modulating their room-temperature phosphorescence (RTP) and thermally activated delayed fluorescence (TADF) properties by a host-guest doping strategy. FQs were doped into the boric acid host, forming boronic anhydride structures and hydrogen bonds, which prompted the RTP and TADF performance of FQs by stabilizing their excited states, preventing triplet exciton quenching, and reducing the energy gap between singlet and triplet states. The FQs can be quantitatively detected through monitoring the afterglow intensity of host-guest systems, as low as 0.25 µg/mL. The differences in the afterglow intensity and emission lifetime allowed accurate discrimination of 11 types of FQs through pattern recognition methods. Aided by the delayed signal detection model of afterglow emission, the background signal and the interferences from food matrices were effectively eliminated, which endow the detection and discrimination of mixed FQs in commercial meat samples, without multiple-step separation processes.


Assuntos
Anidridos , Fluoroquinolonas , Bioensaio , Boro , Alimentos
3.
Haematologica ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39234866

RESUMO

Patients with relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL) have a poor prognosis. Loncastuximab tesirine (Lonca), an antibody conjugate targeting CD19, has demonstrated significant clinical benefit in R/R DLBCL in a global phase 2 LOTIS-2 study. In the China bridging pivotal phase 2 OL-ADCT-402-001 study, eligible patients aged ≥18 years with R/R DLBCL who had failed ≥ 2 lines of systemic therapies were enrolled and treated with Lonca every 3 week with 150 µg/kg for 2 cycles; then 75 µg/kg for subsequent cycles (up to 1 year). The primary endpoint was overall response rate (ORR) assessed by independent review committee. Primary analyses for efficacy and safety were performed on the patients who received at least one treatment and had at least 6 months of follow-up following an initial documented response. As of data-cutoff, 64 patients received Lonca (median: 4.0 cycles [range: 1 to 17]). The median number of prior lines of therapies was 3.0 (range: 2 to 12). The ORR was 51.6% (95% CI: 38.7% to 64.2%), and the complete response rate was 23.4%. Hematological events accounted for the majority of the most common (≥15%) Grade ≥3 treatment-emergent adverse events (TEAEs), in which increased gamma glutamyltransferase (25.0%), and hypokalaemia (18.8%) also were reported. Serious TEAEs were reported in 35 of 64 patients with 4 fatal TEAEs. In conclusion, Lonca monotherapy demonstrated clinically meaningful efficacy and was well-tolerated in heavily pretreated Chinese patients with R/R DLBCL, which was consistent with the results of the LOTIS-2 study in Caucasian patients.

4.
Skeletal Radiol ; 53(8): 1651-1656, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38231261

RESUMO

Primary malignant bone tumors of the spine are exceedingly rare, with solitary bone plasmacytoma (SBP) representing approximately 30% of all cases. Radiological assessments are crucial for localizing SBP and for ruling out a diagnosis of multiple myeloma (MM). Imaging features resembling a "mini-brain" appear to be distinctive for SBP. Vertebral lesions accompanied by adjacent disc space involvement typically suggest spinal infections, while the potential for SBP involvement is often overlooked. We present a case of a 61-year-old female with SBP who exhibited thoraco-lumbar spine destruction and adjacent disc space involvement. The patient sought treatment at our medical center due to lumbodorsal pain radiating bilaterally to the inguinal regions. Radiological findings revealed an osteolytic lesion involving the intervertebral disc, making it challenging to distinguish between tumor and inflammation. A biopsy of the vertebral lesion confirmed the diagnosis of SBP, which was further supported by laboratory results. Post-diagnosis, the patient underwent radiotherapy, receiving a total dose of 4000 Gy, which alleviated her symptoms. We also provide a comprehensive literature review on SBP with disc involvement to aid both clinical and radiological diagnoses.


Assuntos
Plasmocitoma , Neoplasias da Coluna Vertebral , Feminino , Humanos , Pessoa de Meia-Idade , Biópsia , Diagnóstico Diferencial , Disco Intervertebral/diagnóstico por imagem , Disco Intervertebral/patologia , Vértebras Lombares/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Plasmocitoma/diagnóstico por imagem , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/patologia , Tomografia Computadorizada por Raios X
5.
Mikrochim Acta ; 191(6): 304, 2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710810

RESUMO

Dual-emissive fluorescence probes were designed by integrating porphyrin into the frameworks of UiO-66 for ratiometric fluorescence sensing of amoxicillin (AMX). Porphyrin integrated UiO-66 showed dual emission in the blue and red region. AMX resulted in the quenching of blue fluorescence component, attributable to the charge neutralization and hydrogen bonds induced energy transfer. AMX was detected using (F438/F654) as output signals. Two linear relationships were observed (from 10 to 1000 nM and 1 to 100 µM), with a limit of detection of 27 nM. The porphyrin integrated UiO-66 probe was used to detect AMX in practical samples. This work widens the road for the development of dual/multiple emissive fluorescence sensors for analytical applications, providing materials and theoretical supporting for food, environmental, and human safety.


Assuntos
Amoxicilina , Antibacterianos , Corantes Fluorescentes , Leite , Porfirinas , Espectrometria de Fluorescência , Leite/química , Porfirinas/química , Antibacterianos/análise , Antibacterianos/química , Amoxicilina/análise , Amoxicilina/química , Corantes Fluorescentes/química , Animais , Espectrometria de Fluorescência/métodos , Limite de Detecção , Estruturas Metalorgânicas/química , Resíduos de Drogas/análise , Contaminação de Alimentos/análise
6.
Mikrochim Acta ; 191(2): 119, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300297

RESUMO

A ratiometric fluorescence platform was developed based on the cobalt oxyhydroxide (CoOOH) nanosheet-modulated fluorescence response of blue emissive copper nanoclusters (Cu NCs) and yellow emissive o-phenylenediamine (OPD). CoOOH nanosheets showed dual function of strong absorption and oxidation ability, which can effectively quench the blue fluorescence of Cu NCs, with an excitation and emission peak maximum at 390 and 450 nm, respectively , and transfer the OPD into yellow fluorescence products, with an excitation and emission peak maximum at 390 and 560 nm, respectively. Upon introducing butyrylcholinesterase (BChE) and its substrates, CoOOH nanosheets were decomposed into Co2+, and malachite green (MG) showed strong inhibition ability to this  process. This resulted in the obvious difference on the ratio of blue and yellow fluorescence recorded on the system in the presence and absence of MG, which was utilized for the quantitative detection of MG, with a limit of detection of 0.140 µM and a coefficient of variation of 3.5%. The fluorescence ratiometric assay showed excellent detection performances in practical sample analysis.


Assuntos
Butirilcolinesterase , Cobalto , Cobre , Óxidos , Fenilenodiaminas , Animais , Corantes de Rosanilina , Peixes
7.
Mikrochim Acta ; 191(11): 668, 2024 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-39400726

RESUMO

Studies have found that matrix metalloproteinase-9 (MMP-9) and interleukin-6 (IL-6) play an important role in tumorigenesis. In order to detect MMP-9 and IL-6 concentrations with high sensitivity and specificity, an efficient microfluidic-SERS sensing system was prepared based on surface-enhanced Raman scattering (SERS). The aptamer recognition-release mechanism and the dual signal amplification strategy were applied in the sensing system. The sensor system was developed using two kinds of nanomaterials with excellent SERS properties, namely gold-coated iron tetroxide particles (Fe3O4@AuNPs) and gold nanocages (AuNCs). In addition, Fe3O4@AuNPs also has magnetic adsorption properties. In the sensing system, single-stranded DNA1 (ssDNA1) and aptamer were modified on Fe3O4@AuNPs. Single-stranded DNA2 (ssDNA2) and Raman tags were modified on AuNCs. When the target was present, the aptamer bound to the target and detached from the Fe3O4@AuNPs, and ssDNA2 bound to the exposed ssDNA1. At this time, the Fe3O4@AuNPs@AuNCs@SERS tag complex was formed, and the SERS signal was enhanced for the first time. Under the action of an external magnet on the microfluidic chip, the complex was magnetized and enriched. The SERS signal was enhanced for the second time. Due to the high affinity between the aptamer and the target object, the sensing system has a strong specificity. The double amplification of the SERS signal gave the system excellent sensitivity. The limit of detection (LOD) relative to MMP-9 and IL-6 were as low as 0.178 pg/mL and 0.165 pg/mL, respectively. The microfluidic-SERS sensing system has a feasible prospect in the early screening of gastric cancer.


Assuntos
Aptâmeros de Nucleotídeos , Ouro , Limite de Detecção , Metaloproteinase 9 da Matriz , Análise Espectral Raman , Neoplasias Gástricas , Aptâmeros de Nucleotídeos/química , Neoplasias Gástricas/diagnóstico , Humanos , Análise Espectral Raman/métodos , Ouro/química , Metaloproteinase 9 da Matriz/análise , Interleucina-6/análise , Nanopartículas Metálicas/química , DNA de Cadeia Simples/química , Técnicas Biossensoriais/métodos , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos
8.
Chemistry ; 29(35): e202300366, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37051734

RESUMO

Selective and sensitive detection of inorganic pyrophosphate (PPi) are of great significance both for clinical applications and fundamental research. In this work, a ratiometric fluorescent probe was developed by decorating a porphyrin-based metal-organic framework (PCN-224) with sulfur nanodots (S-dots). The red-fluorescence of PCN-224 was significantly promoted (more than 6-fold) by S-dots through inhibiting molecular motion of porphyrin ligand, which also provided active sites for the detection of Cu2+ and PPi. Cu2+ could selectively quench the red-fluorescence of PCN-224 through coordination with porphyrin ligand, and the competition reaction between PPi and Cu2+ resulted in the decomposing of coordination and recovery of red-fluorescence. The blue-fluorescence from S-dots was deemed as effective reference, which provided a built-in correction in complex environments. Based on these photophysical properties, a ratiometric fluorescence assay was developed for the quantitative detection of Cu2+ and PPi, with a limit of detection of 0.11 and 2.66 µM, respectively. The accuracy and practical applications of assays were also demonstrated by detection in tap water and human serum samples.


Assuntos
Estruturas Metalorgânicas , Pontos Quânticos , Humanos , Estruturas Metalorgânicas/química , Difosfatos/química , Fluorescência , Ligantes , Bioensaio , Corantes Fluorescentes/química , Espectrometria de Fluorescência , Limite de Detecção , Pontos Quânticos/química
9.
Chemistry ; 29(4): e202202652, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36302702

RESUMO

Developing solid luminescent materials with a unity quantum yield and tunable emission color is promising, although it is still a difficult task. A straightforward heat-treatment method has been developed to load 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) into the matrix of boric acid (BA) to produce powders with a near-unity quantum yield and tunable emission color from yellow to green. Our results suggest that the emission of the powders originates from PTCDA, and the tunability of the emission color is caused by the hydrolysis of PTCDA in the alkaline environment. The near-unity quantum yield is attributed to the BA matrix, which confines PTCDA. In addition, the powder also shows excellent thermal stability that allows its application in light-emitting diodes. The above results are important for the development of solid-state luminescent materials for various applications, and also provide a clue for studying the emission properties of luminescent materials.

10.
Chemistry ; 29(13): e202203554, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36453732

RESUMO

Selective detection of Al3+ is of great significance both for the benefit of human health and environmental safety considerations. In this work, a sensitive and selective fluorescence assay for Al3+ was proposed based on the green-emissive Cu nanoclusters (Cu NCs). Different from the commonly reported works, the green emissive Cu NCs showed dual emission bands at 450 and 510 nm, attributed to the reaction product between polyvinyl pyrrolidone and ascorbic acid and the Cu core, respectively. Al3+ could induce the aggregation of Cu NCs by forming covalent bonds, which results in the enhancement of photoluminescence intensity. This enhancement phenomenon is rather selective to Al3+ , which endows the detection in real samples. These results provide new insights for the fluorescence mechanisms of metal NCs, which also provided a functional luminescent material for various applications, such as chemical sensing, bioimaging and photoelectric devices.

11.
Eur Radiol ; 33(12): 8858-8868, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37389608

RESUMO

OBJECTIVES: To develop and validate a CT-based deep learning radiomics nomogram (DLRN) for outcome prediction in clear cell renal cell carcinoma (ccRCC), and its performance was compared with the Stage, Size, Grade, and Necrosis (SSIGN) score, the University of California, Los Angeles, Integrated Staging System (UISS), the Memorial Sloan-Kettering Cancer Center (MSKCC), and the International Metastatic Renal Cell Database Consortium (IMDC). METHODS: A multicenter of 799 localized (training/ test cohort, 558/241) and 45 metastatic ccRCC patients were studied. A DLRN was developed for predicting recurrence-free survival (RFS) in localized ccRCC patients, and another DLRN was developed for predicting overall survival (OS) in metastatic ccRCC patients. The performance of the two DLRNs was compared with that of the SSIGN, UISS, MSKCC, and IMDC. Model performance was assessed with Kaplan-Meier curves, time-dependent area under the curve (time-AUC), Harrell's concordance index (C-index), and decision curve analysis (DCA). RESULTS: In the test cohort, the DLRN achieved higher time-AUCs (0.921, 0.911, and 0.900 for 1, 3, and 5 years, respectively), C-index (0.883), and net benefit than SSIGN and UISS in predicting RFS for localized ccRCC patients. The DLRN provided higher time-AUCs (0.594, 0.649, and 0.754 for 1, 3, and 5 years, respectively) than MSKCC and IMDC in predicting OS for metastatic ccRCC patients. CONCLUSIONS: The DLRN can accurately predict outcomes and outperformed the existing prognostic models in ccRCC patients. CLINICAL RELEVANCE STATEMENT: This deep learning radiomics nomogram may facilitate individualized treatment, surveillance, and adjuvant trial design for patients with clear cell renal cell carcinoma. KEY POINTS: • SSIGN, UISS, MSKCC, and IMDC may be insufficient for outcome prediction in ccRCC patients. • Radiomics and deep learning allow for the characterization of tumor heterogeneity. • The CT-based deep learning radiomics nomogram outperforms the existing prognostic models in ccRCC outcome prediction.


Assuntos
Carcinoma de Células Renais , Aprendizado Profundo , Neoplasias Renais , Humanos , Carcinoma de Células Renais/diagnóstico por imagem , Prognóstico , Nomogramas , Neoplasias Renais/diagnóstico por imagem , Estadiamento de Neoplasias , Tomografia Computadorizada por Raios X , Estudos Retrospectivos
12.
Eur Radiol ; 33(9): 6608-6618, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37012548

RESUMO

OBJECTIVES: The aim of the study was to evaluate the association between the radiomics-based intratumoral heterogeneity (ITH) and the recurrence risk in hepatocellular carcinoma (HCC) patients after liver transplantation (LT), and to assess its incremental to the Milan, University of California San Francisco (UCSF), Metro-Ticket 2.0, and Hangzhou criteria. METHODS: A multicenter cohort of 196 HCC patients were investigated. The endpoint was recurrence-free survival (RFS) after LT. A CT-based radiomics signature (RS) was constructed and assessed in the whole cohort and in the subgroups stratified by the Milan, UCSF, Metro-Ticket 2.0, and Hangzhou criteria. The R-Milan, R-UCSF, R-Metro-Ticket 2.0, and R-Hangzhou nomograms which combined RS and the four existing risk criteria were developed respectively. The incremental value of RS to the four existing risk criteria in RFS prediction was evaluated. RESULTS: RS was significantly associated with RFS in the training and test cohorts as well as in the subgroups stratified by the existing risk criteria. The four combined nomograms showed better predictive capability than the existing risk criteria did with higher C-indices (R-Milan [training/test] vs. Milan, 0.745/0.765 vs. 0.677; R-USCF vs. USCF, 0.748/0.767 vs. 0.675; R-Metro-Ticket 2.0 vs. Metro-Ticket 2.0, 0.756/0.783 vs. 0.670; R-Hangzhou vs. Hangzhou, 0.751/0.760 vs. 0.691) and higher clinical net benefit. CONCLUSIONS: The radiomics-based ITH can predict outcomes and provide incremental value to the existing risk criteria in HCC patients after LT. Incorporating radiomics-based ITH in HCC risk criteria may facilitate candidate selection, surveillance, and adjuvant trial design. KEY POINTS: • Milan, USCF, Metro-Ticket 2.0, and Hangzhou criteria may be insufficient for outcome prediction in HCC after LT. • Radiomics allows for the characterization of tumor heterogeneity. • Radiomics adds incremental value to the existing criteria in outcome prediction.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/etiologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/etiologia , Transplante de Fígado/efeitos adversos , Recidiva Local de Neoplasia/patologia , Prognóstico , Estudos Retrospectivos
13.
J Comput Assist Tomogr ; 47(2): 199-204, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36790871

RESUMO

PURPOSE: Previous studies have pointed out that magnetic resonance- and fluorodeoxyglucose positron emission tomography-based radiomics had a high predictive value for the response of the neoadjuvant chemotherapy (NAC) in breast cancer by respectively characterizing tumor heterogeneity of the relaxation time and the glucose metabolism. However, it is unclear whether computed tomography (CT)-based radiomics based on density heterogeneity can predict the response of NAC. This study aimed to develop and validate a CT-based radiomics nomogram to predict the response of NAC in breast cancer. METHODS: A total of 162 breast cancer patients (110 in the training cohort and 52 in the validation cohort) who underwent CT scans before receiving NAC and had pathological response results were retrospectively enrolled. Grades 4 to 5 cases were classified as response to NAC. According to the Miller-Payne grading system, grades 1 to 3 cases were classified as nonresponse to NAC. Radiomics features were extracted, and the optimal radiomics features were obtained to construct a radiomics signature. Multivariate logistic regression was used to develop the clinical prediction model and the radiomics nomogram that incorporated clinical characteristics and radiomics score. We assessed the performance of different models, including calibration and clinical usefulness. RESULTS: Eight optimal radiomics features were obtained. Human epidermal growth factor receptor 2 status and molecular subtype showed statistical differences between the response group and the nonresponse group. The radiomics nomogram had more favorable predictive efficacy than the clinical prediction model (areas under the curve, 0.82 vs 0.70 in the training cohort; 0.79 vs 0.71 in the validation cohort). The Delong test showed that there are statistical differences between the clinical prediction model and the radiomics nomogram ( z = 2.811, P = 0.005 in the training cohort). The decision curve analysis showed that the radiomics nomogram had higher overall net benefit than the clinical prediction model. CONCLUSION: The radiomics nomogram based on CT radiomics signature and clinical characteristics has favorable predictive efficacy for the response of NAC in breast cancer.


Assuntos
Neoplasias da Mama , Biologia Computacional , Tomografia Computadorizada por Raios X , Biologia Computacional/normas , Tomografia Computadorizada por Raios X/normas , Terapia Neoadjuvante , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Valor Preditivo dos Testes , Estudos Retrospectivos , Modelos Estatísticos , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
14.
Eur J Nucl Med Mol Imaging ; 49(8): 2949-2959, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35344062

RESUMO

PURPOSE: Tumor heterogeneity, which is associated with poor outcomes, has not been exhibited in the University of California, Los Angeles, Integrated Staging System (UISS), and the Stage, Size, Grade and Necrosis (SSIGN) scores. Radiomics allows an in-depth characterization of heterogeneity across the tumor, but its incremental value to the existing prognostic models for clear cell renal cell carcinoma (ccRCC) outcome is unknown. The purpose of this study was to evaluate the association between the radiomics-based tumor heterogeneity and postoperative risk of recurrence in localized ccRCC, and to assess its incremental value to UISS and SSIGN. METHODS: A multicenter 866 ccRCC patients derived from 12 Chinese hospitals were studied. The endpoint was recurrence-free survival (RFS). A CT-based radiomics signature (RS) was developed and assessed in the whole cohort and in the subgroups stratified by UISS and SSIGN. Two combined nomograms, the R-UISS (combining RS and UISS) and R-SSIGN (combining RS and SSIGN), were developed. The incremental value of RS to UISS and SSIGN in RFS prediction was evaluated. R statistical software was used for statistics. RESULTS: Patients with low radiomics scores were 4.44 times more likely to experience recurrence than those with high radiomics scores (P<0.001). Stratified analysis suggested the association is significant among low- and intermediate-risk patients identified by UISS and SSIGN. The R-UISS and R-SSIGN showed better predictive capability than UISS and SSIGN did with higher C-indices (R-UISS vs. UISS, 0.74 vs. 0.64; R-SSIGN vs. SSIGN, 0.78 vs. 0.76) and higher clinical net benefit. CONCLUSIONS: The radiomics-based tumor heterogeneity can predict outcome and add incremental value to the existing prognostic models in localized ccRCC patients. Incorporating radiomics-based tumor heterogeneity in ccRCC prognostic models may provide the opportunity to better surveillance and adjuvant clinical trial design.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/patologia , Estudos de Coortes , Humanos , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Estadiamento de Neoplasias , Nefrectomia , Prognóstico , Estudos Retrospectivos
15.
Chemistry ; 28(61): e202201990, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-35916261

RESUMO

Producing high performance phosphors using abundant and non-toxic precursors yet straightforward methods are promising but still a challenging task. Herein, highly luminescent and thermally stable phosphors were fabricated through an in situ precipitation synthesis strategy. Sulfur nanodots (S-dots) act as the precursors for precipitation reactions and also provide the luminescent centers. Structural and optical characterization investigations suggest that S-dots are incorporated in the matrix of BaSO4 , and BaSO4 provides passivation effect for the surface ligands or traps of S-dots. This results in the promotion of photoluminescence quantum yield from 23 % to 58 %, and the BaSO4 matrix also leads to the obvious promotion of thermal stability. These merits endow the construction of phosphor-based light-emitting diodes by utilizing the S-dots@BaSO4 hybrid phosphors as a color conversion layer. These research results are significant for developing sulfur-based luminescent materials, and also provide a solid and universal theory to produce high quality phosphors.


Assuntos
Luminescência , Enxofre
16.
Eur Radiol ; 32(8): 5577-5587, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35192012

RESUMO

OBJECTIVES: To investigate the effects of O6-methylguanine DNA methyltransferase (MGMT) promoter methylation status of gliomas on O-(2-18F-fluoroethyl)-L-tyrosine ([18F]FET) uptake and cerebral blood flow (CBF) of arterial spin labeling (ASL), evaluated by hybrid PET/MR. Stereotactic biopsy was used to validate the findings. METHODS: A set of whole tumor and reference volumes of interest (VOIs) based on PET/FLAIR imaging were delineated and transferred to the corresponding [18F]FET PET and CBF maps in 57 patients with newly diagnosed gliomas. The mean and max tumor-to-brain ratio (TBR) and normalized CBF (nCBF) were calculated. The predictive efficacy of [18F]FET PET and CBF in determining MGMT promoter methylation status of glioma were evaluated by whole tumor analysis and stereotactic biopsy. The correlation between PET/MR parameters and MGMT promoter methylation were analyzed using histological specimens acquired from multiple stereotactic biopsies. RESULTS: Based on the analysis of whole tumor volume and biopsy site, TBRmean, TBRmax, nCBFmean, and nCBFmax showed no statistically significant differences between gliomas with and without MGMT promoter methylation (all p > 0.05). Furthermore, stereotactic biopsy demonstrated that TBRmean, TBRmax, nCBFmean, and nCBFmax showed no correlation with MGMT promoter methylation (r = -0.117, p = 0.579; r = -0.161, p = 0.443; r = -0.271, p = 0.191; r = -0.300, p = 0.145; respectively). CONCLUSIONS: MGMT promoter methylation status shows no effect on [18F]FET uptake and CBF of ASL in gliomas. Stereotactic biopsy validates it and further reveals there is no correlation of [18F]FET PET uptake and CBF with the percentages of MGMT promoter methylation. KEY POINTS: • Based on whole tumor VOI assessment, MGMT promoter methylation status shows no effect on [18F]FET uptake and CBF of ASL in gliomas. • For WHO grade IV glioblastomas, [18F]FET PET and ASL parameters based on hybrid PET/MR fail to predict the MGMT promoter methylation status. • Stereotactic image-based histology reveals that there is no correlation of [18F]FET PET uptake and CBF with the status and percentages of MGMT promoter methylation in gliomas.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Glioma/diagnóstico por imagem , Glioma/genética , Humanos , Imageamento por Ressonância Magnética/métodos , Metilação , Tomografia por Emissão de Pósitrons/métodos , Proteínas Supressoras de Tumor/genética , Tirosina
17.
Mol Imaging ; 2021: 5565932, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33746628

RESUMO

Objective: To evaluate the diagnostic efficacy of MDA-MB-231 triple-negative breast cancer with 125I-labeled pHLIP (Var7) by single-photon emission computed tomography/computed tomography (SPECT/CT) imaging. Methods: The binding fraction of [125I]I-pHLIP (Var7) and MDA-MB-231 cells was measured at pH 7.4 and pH 6.0, and tumor-bearing mice were subjected to small-animal SPECT/CT imaging studies. Results: At pH = 6.0, the binding fractions of [125I]I-pHLIP (Var7) and MDA-MB-231 cells at 10 min, 40 min, 1 h, and 2 h were 1.9 ± 0.1%, 3.5 ± 0.1%, 6.3 ± 0.8%, and 6.6 ± 0.3%, respectively. At pH = 7.4, there was no measured binding between [125I]I-pHLIP (Var7) and MDA-MB-231 cells. Small-animal SPECT/CT imaging showed clearly visible tumors at 1 and 2 h after injection. Conclusions: [125I]I-pHLIP (Var7) could bind to MDA-MB-231 cells in an acidic environment, and small-animal SPECT/CT imaging showed clear tumors at 1 and 2 h after probe injection.


Assuntos
Neoplasias de Mama Triplo Negativas , Microambiente Tumoral , Animais , Linhagem Celular Tumoral , Humanos , Radioisótopos do Iodo , Camundongos , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem
18.
Eur J Nucl Med Mol Imaging ; 48(11): 3656-3665, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33813592

RESUMO

PURPOSE: To construct an FDG PET/CT metabolic parameter-based model to predict early recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT). METHODS: A total of 62 patients with HCC after LT were enrolled with a follow-up period of 1 year. Basic clinical, pathology, and laboratory data, CT features (CPLC), and PET metabolic parameters (CPLCP) were collected for model construction. A CPLC nomogram without metabolic parameters and a CPLCP nomogram with metabolic parameters were established. The net reclassification index (NRI) and integrated discrimination improvement (IDI) of the two models were calculated. The constructed model was compared with Milan criteria and University of California San Francisco (UCSF) criteria. The time-dependent area under the receiver operating characteristic curve (time-AUC) was used to compare the efficiency of the models, and the bootstrap method was used to for verification. Harrell's concordance index (C-index) was used to evaluate the performance of these models. Decision curve analysis (DCA) was used to evaluate the clinical practicability of each model. RESULTS: Thirty out of 62 patients experienced a recurrence during the 1-year follow-up. BCLC stage (P = 0.009), MVI (P = 0.032), AFP (P = 0.004), CTdmax (P = 0.033), and MTV (P = 0.039) were the independent predictors. The CPLC nomogram and the CPLCP nomogram were established. Compared with the CPLC nomogram, the NRI of the CPLCP nomogram increased by 38.98% (95% CI = -18.77-60.43%) and the IDI increased by 4.40% (95% CI = -1.00-16.62%). The AUC value of the CPLCP nomogram was higher than those of Milan criteria and UCSF criteria in the time-AUC curve. Moreover, the CPLCP nomogram had a higher C-index (0.774) than other models. Finally, the DCA curve showed that clinical practicability of the CPLCP nomogram outperformed the Milan criteria and UCSF criteria. CONCLUSIONS: The CPLCP nomogram combining basic clinical data, pathology data, laboratory data, CT features, and PET metabolic parameters showed good efficacy and high clinical practicability in predicting the early recurrence of HCC after LT.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Carcinoma Hepatocelular/diagnóstico por imagem , Fluordesoxiglucose F18 , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Recidiva Local de Neoplasia/diagnóstico por imagem , Nomogramas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Retrospectivos
19.
Eur J Nucl Med Mol Imaging ; 48(1): 217-230, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32451603

RESUMO

PURPOSE: Lymphovascular invasion (LVI) impairs surgical outcomes in lung adenocarcinoma (LAC) patients. Preoperative prediction of LVI is challenging by using traditional clinical and imaging parameters. The purpose of this study was to investigate the value of the radiomics nomogram integrating clinical factors, CT features, and maximum standardized uptake value (SUVmax) to predict LVI and outcome in LAC and to evaluate the additional value of the SUVmax to the PET/CT-based radiomics nomogram. METHODS: A total of 272 LAC patients (87 LVI-present LACs and 185 LVI-absent LACs) with PET/CT scans were retrospectively enrolled, and 160 patients with SUVmax ≥ 2.5 of them were used for PET radiomics analysis. Clinical data and CT features were analyzed to select independent LVI predictors. The performance of the independent LVI predictors and SUVmax was evaluated. Two-dimensional (2D) and three-dimensional (3D) CT radiomics signatures (RSs) and PET-RS were constructed with the least absolute shrinkage and selection operator algorithm and radiomics scores (Rad-scores) were calculated. The radiomics nomograms, incorporating Rad-score and independent clinical and CT factors, with SUVmax (RNWS) or without SUVmax (RNWOS) were built. The performance of the models was assessed with respect to calibration, discrimination, and clinical usefulness. All the clinical, PET/CT, pathologic, therapeutic, and radiomics parameters were assessed to identify independent predictors of progression-free survival (PFS). RESULTS: CT morphology was the independent LVI predictor. SUVmax provided better discrimination capability compared with CT morphology in the training set (P < 0.001) and test set (P = 0.042). A total of 1409 CT and PET radiomics features were extracted and reduced to 8, 8, and 10 features to build the 2D CT-RS, 3D CT-RS, and the PET-RS, respectively. There was no significant difference in AUC between the 2D-RS and 3D-RS (P > 0.05), and 2D CT-RS showed a relatively higher AUC than 3D CT-RS. The CT-RS, the CT-RNWOS, and the CT-RNWS showed good discrimination in the training set (AUC [area under the curve], 0.799, 0.796, and 0.851, respectively) and the test set (AUC, 0.818, 0.822, and 0.838, respectively). There was significant difference in AUC between the CT-RNWS and CT-RNWOS (P = 0.044) in the training set. Decision curve analysis (DCA) demonstrated the CT-RNWS outperformed the CT-RS and the CT-RNWOS in terms of clinical usefulness. Furthermore, DCA showed the PETCT-RNWS provided the highest net benefit compared with the PET-RNWS and CT-RNWS. PFS was significantly different between the pathologic and RNWS-predicted LVI-present and LVI-absent patients (P < 0.001). Carbohydrate antigen 125 (CA125), carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), pathologic LVI, histologic subtype, and SUVmax were independent predictors of PFS in the 244 CT-RNWS-predicted cohort; and CA125, NSE, pathologic LVI, and SUVmax were the independent predictors of PFS in the 141 PETCT-RNWS-predicted cohort. CONCLUSIONS: The radiomics nomogram, incorporating Rad-score, clinical and PET/CT parameters, shows favorable predictive efficacy for LVI status in LAC. Pathologic LVI and SUVmax are associated with LAC prognosis.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/diagnóstico por imagem , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Nomogramas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
20.
Mol Pharm ; 18(3): 787-795, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33480702

RESUMO

Most oligonucleotides fail to enter a cell and cannot escape from endosomes after endocytosis because of their negative charge and large molecular weight. More efficient cellular delivery of oligonucleotides should be developed for the widespread implementation of antisense imaging. The purpose of this study was to construct a novel antisense nanoprobe, 99mTc-labeled anti-miRNA oligonucleotides/cell-penetrating peptide PepFect6 (99mTc-AMO/PF6), and to evaluate its efficacy for imaging the miRNA-21 expression in A549 lung adenocarcinoma xenografts. Naked AMO and commercial Lipofectamine 2000-based nanoparticles (AMO/LIP) were used for comparison. The cellular delivery efficiency of AMO/PF6 was first investigated by laser confocal scanning microscopy using Cy5.5-labeled probes and further validated by in vivo fluorescence imaging. Then, the probes were labeled with 99mTc via hydrazinonicotinamide (HYNIC). The cytotoxicity assay, cellular uptake, and retention kinetics of the probes were evaluated in vitro. The biodistribution of the probes was investigated in A549 lung cancer xenografts, and SPECT imaging was performed in vivo. AMO/PF6 showed lower cytotoxicity than AMO/LIP (P < 0.05) but showed no significant difference with naked AMO. Fluorescence microscopy demonstrated more extensive and scattered signal distribution inside the A549 cells by AMO/PF6 than AMO/LIP. The labeling efficiency of 99mTc-AMO/PF6 was 72.6 ± 1.42%, and the specific activity was 11.6 ± 0.13 MBq/ng. The cellular uptake of 99mTc-PF6/AMO peaked at 12 h, with the uptake of 11.24 ± 0.12 mol/cell × 10-16, and the cellular retention of 99mTc-AMO/PF6 was 3.92 ± 0.15 mol/cell × 10-16 at 12 h after interrupted incubation. AMO/PF6 showed higher cellular uptake and retention than naked AMO and AMO/LIP. The biodistribution study showed that the tumor had the highest radioactivity accumulation, with the uptake ratio of tumor/muscle (T/M) increasing from 14.59 ± 0.67 to 21.76 ± 0.98 between 1 and 6 h after injection, followed by the uptake in the kidneys and the liver. The results of in vivo fluorescence and SPECT imaging were consistent with the results of the biodistribution. The tumor was visualized at 6 h after injection of AMO/PF6 with the highest T/M ratio among these probes (P < 0.05). PF6 improves cellular delivery of antisense oligonucleotides via noncovalent nanoparticles. 99mTc-AMO/PF6 shows favorable imaging properties and is promising for miRNAs imaging in vivo.


Assuntos
Peptídeos Penetradores de Células/metabolismo , MicroRNAs/metabolismo , Oligonucleotídeos Antissenso/metabolismo , Células A549 , Animais , Linhagem Celular Tumoral , Humanos , Marcação por Isótopo/métodos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Compostos Radiofarmacêuticos/metabolismo , Distribuição Tecidual/fisiologia , Tomografia Computadorizada de Emissão de Fóton Único/métodos
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