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1.
Proc Natl Acad Sci U S A ; 120(13): e2215324120, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36940343

RESUMO

Disparities continue to pose major challenges in various aspects of science. One such aspect is editorial board composition, which has been shown to exhibit racial and geographical disparities. However, the literature on this subject lacks longitudinal studies quantifying the degree to which the racial composition of editors reflects that of scientists. Other aspects that may exhibit racial disparities include the time spent between the submission and acceptance of a manuscript and the number of citations a paper receives relative to textually similar papers, but these have not been studied to date. To fill this gap, we compile a dataset of 1,000,000 papers published between 2001 and 2020 by six publishers, while identifying the handling editor of each paper. Using this dataset, we show that most countries in Asia, Africa, and South America (where the majority of the population is ethnically non-White) have fewer editors than would be expected based on their share of authorship. Focusing on US-based scientists reveals Black as the most underrepresented race. In terms of acceptance delay, we find, again, that papers from Asia, Africa, and South America spend more time compared to other papers published in the same journal and the same year. Regression analysis of US-based papers reveals that Black authors suffer from the greatest delay. Finally, by analyzing citation rates of US-based papers, we find that Black and Hispanic scientists receive significantly fewer citations compared to White ones doing similar research. Taken together, these findings highlight significant challenges facing non-White scientists.


Assuntos
Autoria , Publicações , Humanos , Ásia , População Negra , Hispânico ou Latino
2.
J Am Chem Soc ; 146(23): 15730-15739, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38776525

RESUMO

NAD(P)H cofactor is a critical energy and electron carrier in biocatalysis and photosynthesis, but the artificial reduction of NAD(P)+ to regenerate bioactive 1,4-NAD(P)H with both high activity and selectivity is challenging. Herein, we found that a coupled system of a Ni3S2 electrode and a Rh complex in an electrolyte (denoted as Ni3S2-Rh) can catalyze the reduction of NAD(P)+ to 1,4-NAD(P)H with superior activity and selectivity. The optimized selectivity in 1,4-NADH can be up to 99.1%, much higher than that for Ni3S2 (80%); the normalized activity of Ni3S2-Rh is about 5.8 times that of Ni3S2 and 13.2 times that of the Rh complex. The high performance of Ni3S2-Rh is attributed to the synergistic effect between metal sulfides and Rh complex. The NAD+ reduction reaction proceeds via a concerted electron-proton transfer (CEPT) mechanism in the Ni3S2-Rh system, in which Ni3S2 acts as a proton and electron-transfer mediator to accelerate the formation of Rh hydride (Rh-H), and then the Rh-H regioselectively transfers the hydride to NAD+ to form 1,4-NADH. The artificial system Ni3S2-Rh essentially mimics the functions of ferredoxin-NADP+ reductase in nature.

3.
Mol Carcinog ; 63(5): 938-950, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38353288

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a highly invasive cancer with a poor prognosis and a 5-year survival rate of less than 11%. As a member of the CAP superfamily of proteins, the role of peptidase inhibitor 16 (Pi16) in tumor progression is still unclear. Immunohistochemistry and quantitative RT-PCR methods were used to detect the expression levels of Pi16 protein and mRNA in PDAC patients. CRISPR/Cas9 technology was used to knock out the expression of Pi16 in PDAC cell lines. In vivo and in vitro experiments were used to verify the effect of Pi16 on PDAC proliferation ability. By RNA sequencing, we found that oligoadenylate synthetase L (OASL) can serve as a potential downstream target of Pi16. The expression of Pi16 was higher in PDAC tissues than in matched adjacent tissues. High expression of Pi16 was associated with PDAC progression and poor prognosis. Overexpression of Pi16 could promote the proliferation of PDAC cells in vitro and in vivo. Bioinformatics analysis and coimmunoprecipitation assays showed that Pi16 could bind to OASL. Moreover, the functional recovery test confirmed that Pi16 could promote the proliferation of PDAC via OASL. Our present study demonstrates that Pi16 might participate in the occurrence and development of PDAC by regulating cell proliferation by binding to OASL, indicating that Pi16 might be a promising novel therapeutic target for PDAC.


Assuntos
2',5'-Oligoadenilato Sintetase , Nucleotídeos de Adenina , Carcinoma Ductal Pancreático , Glicoproteínas , Neoplasias Pancreáticas , Humanos , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Glicoproteínas/metabolismo , Proteínas de Transporte/metabolismo , 2',5'-Oligoadenilato Sintetase/metabolismo
4.
Appl Opt ; 63(7): 1744-1752, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437276

RESUMO

Small-sized, highly sensitive dynamic pressure sensors are crucial in the field of turbomachinery application. In this paper, a fiber-tip structure dynamic pressure sensor utilizing a small piece of glass tube as the air cavity and PDMS material as the diaphragm was fabricated. It has the advantage of being small in size with the diameter of 125 µm while having high sensitivity of 26.26 pm/kPa. The fabrication process was described in detail, which is simple and cost-effective. The sensor characteristics were studied theoretically and experimentally. Quasi-square pressure signal of different frequencies generated by the siren disk were measured by the sensor and compared with that obtained from the commercial piezoresistive pressure sensor to verify the accuracy of the proposed sensor. The R2 of the four pairs of pressure waveforms were 0.94, 0.81, 0.93, and 0.96, respectively. Stability testing of the sensor was also performed, showing that the sensor can work reliably under dynamic pressure environment.

5.
Compr Rev Food Sci Food Saf ; 23(3): e13328, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38551068

RESUMO

The incomplete absorption of dietary folate makes it crucial to understand how food matrices affect folate bioaccessibility. Bioavailability encompasses bioaccessibility, which depicts the proportion that is liberated from the food matrix during digestion and becomes available for absorption. Bioavailability studies are expensive and difficult to control, whereas bioaccessibility studies utilize in vitro digestion models to parameterize the complex digestion, allowing the evaluation of the effect of food matrices on bioaccessibility. This review covers the folate contents in various food matrices, the methods used to determine and the factors affecting folate bioaccessibility, and the advances and challenges in understanding how food matrices affect folate bioaccessibility. The methods for determining bioaccessibility have been improved in the last decade. Current research shows that food matrices modulate folate bioaccessibility by affecting the liberation and stability of folate during digestion but do not provide enough information about folate and food component interactions at the molecular level. In addition, information on folate interconversion and degradation during digestion is scant, hindering our understanding of the impact of food matrices on folate stability. Moreover, the role of conjugase inhibitors should not be neglected when evaluating the nutritional value of food folates. Due to the complexity of food digestion, holistic methods should be applied to investigate bioaccessibility. By synthesizing the current state of knowledge on this topic, this review highlights the lack of in-depth understanding of the mechanisms of how food matrices modulate folate bioaccessibility and provides insights into potential strategies for accurate evaluation of the nutritional value of dietary folate.


Assuntos
Digestão , Ácido Fólico , Ácido Fólico/análise , Ácido Fólico/metabolismo , Alimentos , Valor Nutritivo
6.
Telemed J E Health ; 29(2): 253-260, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35671521

RESUMO

Background: The widespread use of telemedicine systems and medical information networks has made telemedicine one of the current trends in health care. The purpose of this article is to propose a community health intervention with remote monitoring and teleconsultation during COVID-19 for the prevention and control of COVID-19 at the rural level. Methods: In this intervention study, a randomized group of 1,500 community residents was selected. A questionnaire with acceptable validity and reliability was used to collect data. The study was conducted with the test group itself as a control, and the questionnaire was completed again 6 months after the health intervention through remote monitoring. The extent of the effect of the remote monitoring intervention on community health during COVID-19 was measured. The data were entered into SPSS 26, and the data were analyzed using the K-S normality test, t-test, and chi-square test. Results: After 6 months of the intervention, the differences in mean scores of the test group were statistically significant (p < 0.05) in cognition, perceived benefits, self-efficacy, and behavioral outcomes, with a substantial increase in mean scores for all variables. Conclusions: The application of remote monitoring during COVID-19 in rural communities can influence the health perception, benefit perception, self-efficacy, and behavior of community residents, thus effectively preventing and controlling the spread of COVID-19 in rural communities. It reduces medical barriers for rural areas while meeting.


Assuntos
COVID-19 , Consulta Remota , Telemedicina , Humanos , Saúde Pública , Reprodutibilidade dos Testes
7.
J Formos Med Assoc ; 120(1 Pt 3): 688-696, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32739147

RESUMO

BACKGROUND/PURPOSE: We sought to compare the diagnostic performances of 68Ga-PSMA-11 PET/CT and prostate/whole-abdomen multiparametric magnetic resonance imaging (PWAmpMRI) in Taiwanese patients with biochemically recurrent prostate cancer following robot-assisted radical prostatectomy. METHODS: Between June 2017 and December 2018, we prospectively enrolled 34 patients. Upon review of all available clinical and imaging data, a best valuable comparator (BVC) was defined on an individual basis in the light of a consensus reached by a multidisciplinary tumor board. Diagnostic positivity was investigated in relation to the different lesion types. RESULTS: On a patient-based analysis, 68Ga-PSMA-11 PET/CT and PWAmpMRI showed a moderate agreement (kappa coefficient = 0.62). 68Ga-PSMA-11 PET/CT identified local recurrences, regional, and non-regional lymph node metastases, and bone metastases in 15, 10, 1, and 5 patients, respectively. Conversely, PWAmpMRI detected these lesions in 26, 8, 1, and 4 patients, respectively. When the BVC was used as reference standard, the positive diagnostic rates for local recurrences, regional lymph node metastases, non-regional lymph node metastases, and bone metastases were 57.7%, 90.9%, 100%, and 100%, respectively for 68Ga-PSMA-11 PET/CT, and 100%, 72.7%, 100%, and 80% for PWAmpMRI, respectively. The use of both PWAmpMRI and 68Ga-PSMA-11 PET/CT showed a complete diagnostic yield for detecting both local recurrence and systemic failure when PSA levels reached 0.5 ng/mL. CONCLUSION: Due to urine radioactivity, 68Ga-PSMA-11 PET/CT performs less than PWAmpMRI on local recurrences. However, it can have a complementary diagnostic role in the detection of lymph node metastases and in identifying non-axial bone metastases beyond the PWAmpMRI scanning field.


Assuntos
Neoplasias da Próstata , Ácido Edético/análogos & derivados , Isótopos de Gálio , Radioisótopos de Gálio , Humanos , Imageamento por Ressonância Magnética , Masculino , Imageamento por Ressonância Magnética Multiparamétrica , Recidiva Local de Neoplasia/diagnóstico por imagem , Oligopeptídeos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prostatectomia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Robótica
8.
Molecules ; 26(7)2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33918502

RESUMO

Electroactive biomaterials are fascinating for tissue engineering applications because of their ability to deliver electrical stimulation directly to cells, tissue, and organs. One particularly attractive conductive filler for electroactive biomaterials is silver nanoparticles (AgNPs) because of their high conductivity, antibacterial activity, and ability to promote bone healing. However, production of AgNPs involves a toxic reducing agent which would inhibit biological scaffold performance. This work explores facile and green synthesis of AgNPs using extract of Cilembu sweet potato and studies the effect of baking and precursor concentrations (1, 10 and 100 mM) on AgNPs' properties. Transmission electron microscope (TEM) results revealed that the smallest particle size of AgNPs (9.95 ± 3.69 nm) with nodular morphology was obtained by utilization of baked extract and ten mM AgNO3. Polycaprolactone (PCL)/AgNPs scaffolds exhibited several enhancements compared to PCL scaffolds. Compressive strength was six times greater (3.88 ± 0.42 MPa), more hydrophilic (contact angle of 76.8 ± 1.7°), conductive (2.3 ± 0.5 × 10-3 S/cm) and exhibited anti-bacterial properties against Staphylococcus aureus ATCC3658 (99.5% reduction of surviving bacteria). Despite the promising results, further investigation on biological assessment is required to obtain comprehensive study of this scaffold. This green synthesis approach together with the use of 3D printing opens a new route to manufacture AgNPs-based electroactive with improved anti-bacterial properties without utilization of any toxic organic solvents.


Assuntos
Anti-Infecciosos/farmacologia , Química Verde , Ipomoea batatas/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Impressão Tridimensional , Prata/farmacologia , Alicerces Teciduais/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Coloides/química , Força Compressiva , Difusão Dinâmica da Luz , Módulo de Elasticidade , Condutividade Elétrica , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Poliésteres/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Molhabilidade , Difração de Raios X
9.
J Formos Med Assoc ; 119(4): 793-804, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31818713

RESUMO

BACKGROUND/PURPOSE: Ovarian clear cell carcinoma (OCCC) with recurrence/progression after treatment has dismal prognosis. We aimed to investigate the management and outcomes of such patients. METHODS: OCCC patients who were treated between 2000 and 2013 with cancer recurrence or progression after primary treatment were analyzed. Univariate and multivariate analyses were used to identify the independent predictors of survival after recurrence (SAR) and cancer-specific survival (CSS). RESULTS: A total of 64 patients experienced treatment failure (49 recurred after remission and 15 progressed without remission). The 5-year CSS rates of recurrent/progressive OCCC patients were 22.9% (progression group: median CSS 5.9 months [range, 0.8-25.2] vs recurrence group: 43.6 months [range, 7.1-217.8]; p < 0.001). Patients with solitary recurrence had significantly better SAR than those with disseminated relapse (median: not reached vs 10.4 months, p < 0.001). On multivariate analysis, six models each for SAR and CSS were formulated alternatively including highly correlated variables for the recurrence group. Of these models, solitary relapse pattern (HR: 0.07, p < 0.001), progression-free interval (PFI) > 12 months (HR: 0.22-0.40, p = 0.001 and p = 0.023), CA125 < 35 U/mL at initial recurrence (HR: 0.32, p = 0.007), and overall salvage treatment including radiotherapy (HR: 0.19, p = 0.001) were significant predictors of favorable SAR. The same significant predictors were selected for CSS. CONCLUSION: Recurrent OCCC can be treated with curative intent if the relapse is solitary and can be completely resected or encompassed with radiotherapy, whereas novel therapies are needed for disseminated relapse or progression during primary treatment.


Assuntos
Adenocarcinoma de Células Claras/terapia , Recidiva Local de Neoplasia/terapia , Neoplasias Ovarianas/terapia , Adenocarcinoma de Células Claras/mortalidade , Adenocarcinoma de Células Claras/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Prognóstico , Taxa de Sobrevida , Taiwan , Falha de Tratamento
10.
Molecules ; 25(1)2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31906347

RESUMO

In this study, the phytochemical profiles, total and cellular antioxidant activities of five different Chinese chestnut (Castanea mollissima BL.) cultivars were analyzed. Phenolics, flavonoids as well as phytochemical compounds in five cultivars of chestnut kernels were determined. Results showed that the free forms played a dominant role in total phenolics, flavonoids and antioxidant activities of all five cultivars of chestnut kernels. The cultivar 'Fyou' showed the highest total and free phenolic contents, 'Heguoyihao' showed the highest total and free flavonoids contents, and 'Chushuhong' showed the highest total and cellular antioxidant activities. Eight phenolic compounds were detected, and chlorogenic acid, gallic acid, and quercetin were shown as three predominant components in all five cultivars. These results provide valuable information which may be a guidance for selection of good chestnut variety to be used as functional food.


Assuntos
Antioxidantes/análise , Antioxidantes/farmacologia , Fagaceae/química , Flavonoides/análise , Fenóis/análise , Compostos Fitoquímicos/análise , Antioxidantes/química , Flavonoides/química , Frutas/química , Células Hep G2 , Humanos , Fenóis/química , Compostos Fitoquímicos/química , Extratos Vegetais/química
11.
Eur Radiol ; 29(2): 556-565, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30051142

RESUMO

OBJECTIVES: To develop and validate a prognostic model of integrating whole-tumour apparent diffusion coefficient (ADC) from pretreatment diffusion-weighted (DW) magnetic resonance (MR) imaging with human papillomavirus (HPV) genotyping in predicting the overall survival (OS) and disease-free survival (DFS) for women with stage IB-IV cervical cancer following concurrent chemoradiotherapy (CCRT). METHODS: We retrospectively analysed three prospectively collected cohorts comprising 300 patients with stage IB-IV cervical cancer treated with CCRT in 2007-2014 and filtered 134 female patients who underwent MR imaging at 3.0 T for final analysis (age, 24-92 years; median, 54 years). Univariate and multivariate Cox regression analyses were used to evaluate the whole-tumour ADC histogram parameters, HPV genotyping and relevant clinical variables in predicting OS and DFS. The dataset was randomly split into training (n = 88) and testing (n = 46) datasets for construction and independent bootstrap validation of the models. RESULTS: The median follow-up time for surviving patients was 69 months (range, 9-126 months). Non-squamous cell type, ADC10 <0.77 × 10-3 mm2/s, T3-4, M1 stage and high-risk HPV status were selected to generate a model, in which the OS and DFS for the low, intermediate and high-risk groups were significantly stratified (p < 0.0001). The prognostic model improved the prediction significantly compared with the International Federation of Gynaecology and Obstetrics (FIGO) stage for both the training and independent testing datasets (p < 0.0001). CONCLUSIONS: The prognostic model based on integrated clinical and imaging data could be a useful clinical biomarker to predict OS and DFS in patients with stage IB-IV cervical cancer treated with CCRT. KEY POINTS: • ADC 10 is the best prognostic factor among ADC parameters in cervical cancer treated with CCRT • A novel prognostic model was built based on histology, ADC 10 , T and M stage and HPV status • The prognostic model outperforms FIGO stage in the survival prediction.


Assuntos
Papillomaviridae/genética , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiorradioterapia/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Genótipo , Técnicas de Genotipagem/métodos , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Papillomaviridae/classificação , Prognóstico , Estudos Retrospectivos , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Adulto Jovem
12.
Molecules ; 24(4)2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30781354

RESUMO

The intention of this study was to investigate the effect of steaming processing on phenolic profiles and antioxidant activities in chestnuts. Steaming processing at different times and temperatures depicted diverse impacts on free and bound fractions. Though, bound phenolics were stable but long time steaming at higher temperatures tended to improve the levels of phenolics, flavonoids as well as antioxidant activities in chestnut kernels, by up to 60.11% of the original value. Seven phenolic compounds including ferulic acid, chlorogenic acid, gallic acid, vanillic acid, syringate, p-coumaric acid and quercetin were found to change during thermal processes. Significant relationships (p < 0.05) were identified between total phenolics and total antioxidant activities. However, the consistency of chlorogenic acid (p < 0.01) only with cellular antioxidant activity indicated poor bio-accessibility of the phytochemicals in chestnuts. However, this situation could be partly improved by steaming. Steaming could improve the cellular accessibility of free phytochemicals, particularly, increasing the bio-accessibility by 41.96%. This study provided valuable information on dynamic changes of phenolic profiles and antioxidant activity of chestnuts under a steaming process, which could offer possible guidance for the chestnut processing industry in the future.


Assuntos
Antioxidantes/química , Fagaceae/química , Fenóis/química , Extratos Vegetais/química , Antioxidantes/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Manipulação de Alimentos , Temperatura Alta , Fenóis/isolamento & purificação , Vapor
13.
Eur J Nucl Med Mol Imaging ; 45(7): 1197-1204, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29470614

RESUMO

PURPOSE: To assess the clinical roles of [18F]fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) performed 2-3 months after completion of concurrent chemoradiotherapy (CCRT), along with pretherapy characteristics, in patients with advanced squamous cell carcinoma of the uterine cervix enrolled in a prospective randomized clinical trial. METHODS: Posttherapy PET/CT in patients with advanced FIGO stage or positive pelvic or para-aortic lymph node (PALN) defined on pretherapy PET/CT was classified as positive, equivocal, or negative. Overall survival (OS) rates between patients with different PET/CT results are compared. Pretherapy characteristics are examined for association with posttherapy PET/CT results and for prognostic significance in patients with equivocal or negative PET/CT. RESULTS: PET/CT scans (n = 55) were positive, equivocal and negative in 9, 13 and 33 patients, respectively. All patients with positive scans were confirmed to have residual or metastatic disease and died despite salvage therapies. There is a significant OS difference between patients with positive and equivocal scans (P < .001) but not between patients with equivocal and negative scans (P = .411). Positive pretherapy PALN is associated with positive posttherapy PET/CT (P = .033) and predicts a poorer survival in patients with equivocal or negative posttherapy PET/CT (P < .001). CONCLUSIONS: Positive PET/CT 2-3 months posttherapy implies treatment failure and novel therapy is necessary to improve outcomes for such patients. A more intense posttherapy surveillance may be warranted in patients with positive pretherapy PALN.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Quimiorradioterapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias do Colo do Útero/diagnóstico por imagem , Carcinoma de Células Escamosas/terapia , Feminino , Fluordesoxiglucose F18 , Humanos , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Estudos Prospectivos , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X , Falha de Tratamento , Neoplasias do Colo do Útero/terapia
14.
Eur J Nucl Med Mol Imaging ; 45(5): 727-734, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29159572

RESUMO

PURPOSE: Our purpose was to assess the diagnostic performance of positron emission tomography/computed tomography (PET/CT) and pelvic/abdominal magnetic resonance imaging (MRI) after concurrent chemoradiotherapy (CCRT) for posttherapy evaluation in patients with advanced cervical cancer. METHODS: Patients with cervical squamous cell carcinoma, either with advanced FIGO stage or with positive pelvic or para-aortic lymph node (PALN), received PET/CT using [18F]fluorodeoxyglucose and MRI including diffusion-weighted imaging between 2 and 3 months after CCRT completion. PET/CT were interpreted independently by two nuclear medicine physicians and MRI by two radiologists using the same scoring system. Active residual tumor was proven by pathological confirmation or disease progression on imaging studies within one year after CCRT and the disease regions were classified as local, regional, PALN, or distant. Patient-based and region-based comparison was performed using the receiver operating characteristic curve analysis. RESULTS: The study included 55 patients and 15 (27%) patients had active residual tumor. The diagnostic performance of PET/CT is significantly superior to that of MRI in patient-based analysis (P = 0.025) and in the detection of local (P = 0.045) and regional (P = 0.014) disease. The patient-based sensitivity, specificity, and accuracy of PET/CT are 60%, 100%, and 89% while those of MRI are 27%, 100%, and 80%. CONCLUSIONS: PET/CT is superior to MRI for posttherapy evaluation in patients with advanced cervical cancer 2-3 months after definitive CCRT, mainly for the detection of residual local and regional disease. Patients with negative or equivocal results should be followed up regularly due to suboptimal sensitivities of imaging.


Assuntos
Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias do Colo do Útero/diagnóstico por imagem , Quimiorradioterapia , Feminino , Fluordesoxiglucose F18 , Humanos , Pessoa de Meia-Idade , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Estudos Prospectivos , Tomografia Computadorizada por Raios X , Neoplasias do Colo do Útero/terapia
15.
Faraday Discuss ; 198: 197-209, 2017 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-28267170

RESUMO

It is a great challenge to develop iron-based highly-efficient and durable catalytic systems for the hydrogen evolution reaction (HER) by understanding and learning from [FeFe]-hydrogenases. Here we report photocatalytic H2 production by a hybrid assembly of a sulfonate-functionalized [FeFe]-hydrogenase mimic (1) and CdSe quantum dot (QD), which is denoted as 1/ß-CD-6-S-CdSe (ß-CD-6-SH = 6-mercapto-ß-cyclodextrin). In this assembly, thiolato-functionalized ß-CD acts not only as a stabilizing reagent of CdSe QDs but also as a host compound for the diiron catalyst, so as to confine CdSe QDs to the space near the site of diiron catalyst. In addition, another two reference systems comprising MAA-CdSe QDs (HMAA = mercaptoacetic acid) and 1 in the presence and absence of ß-CD, denoted as 1/ß-CD/MAA-CdSe and 1/MAA-CdSe, were studied for photocatalytic H2 evolution. The influences of ß-CD and the stabilizing reagent ß-CD-6-S- on the stability of diiron catalyst, the fluorescence lifetime of CdSe QDs, the apparent electron transfer rate, and the photocatalytic H2-evolving efficiency were explored by comparative studies of the three hybrid systems. The 1/ß-CD-6-S-CdSe system displayed a faster apparent rate for electron transfer from CdSe QDs to the diiron catalyst compared to that observed for MAA-CdSe-based systems. The total TON for visible-light driven H2 evolution by the 1/ß-CD-6-S-CdSe QDs in water at pH 4.5 is about 2370, corresponding to a TOF of 150 h-1 in the initial 10 h of illumination, which is 2.7- and 6.6-fold more than the amount of H2 produced from the reference systems 1/ß-CD/MAA-CdSe and 1/MAA-CdSe. Additionally, 1/ß-CD-6-S-CdSe gave 2.4-5.1 fold enhancement in the apparent quantum yield and significantly improved the stability of the system for photocatalytic H2 evolution.

16.
Nanotechnology ; 28(4): 045304, 2017 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-27981949

RESUMO

A one-step graphene patterning method is developed in this paper. A phase shifting mask is used to modulate incident laser beam spatially and generate graphene patterns by laser heating. Periodic graphene nanoribbon and nanomesh structures are fabricated by employing 1D and 2D phase shifting masks, respectively. The noncontact, simple procedure, easy handling and economic properties of this method make it promising towards graphene-based device fabrication.

17.
J Formos Med Assoc ; 116(11): 869-879, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28089190

RESUMO

BACKGROUND: To prospectively evaluate the value of positron emission tomography (PET) or integrated computed tomography (CT) and PET (PET/CT) in the management of documented or suspected recurrent ovarian cancer. METHODS: Patients with ovarian cancer who had completed primary cytoreductive surgery and standard adjuvant chemotherapy were studied to evaluate the following indications: (1) CA125 elevation after complete remission with negative CT or magnetic resonance imaging (MRI) result; (2) post-therapy surveillance CT/MRI-detected suspicious lesions that guided biopsy was not feasible; (3) documented relapse for restaging prior to or after curative salvage therapy. The clinical impact of PET, as compared with those of CT/MRI, was determined on a per scan basis. RESULTS: From 2002 to 2009, 73 patients were recruited, and 92 PET scans were performed. Up to June 2015, 53 patients had died of disease, four were alive with disease, and the remaining 16 were alive without disease. Among the 92 scans, PET had positive impacts in 72.8%, no clinical impacts in 21.7%, and negative impacts in 5.4%. For indication 1, the sensitivity and positive predictive value of PET in detecting recurrence were 80.0% and 92.3%, respectively. For indication 2, the sensitivity, specificity, positive predictive value, and negative predictive value of PET were 91.2%, 62.5%, 91.2%, and 62.5%, respectively. For indication 3, PET provided positive impact in 85.3% and negative impact in 2.9% of the 34 scans. CONCLUSION: PET has value in the management of suspected or documented recurrent ovarian cancer, with positive impacts on confirming recurrent status and offering a better treatment plan.


Assuntos
Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/patologia , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Retrospectivos , Sensibilidade e Especificidade , Taiwan
18.
Int J Mol Sci ; 18(6)2017 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-28604597

RESUMO

Sweet corn is one of the most widely planted crops in China. Sprouting of grains is a new processes to increase the nutritional value of grain products. The present study explores the effects of light on the nutritional quality of sweet corn sprouts. Gene expression of phenolic biosynthesis, phytochemical profiles and antioxidant activity were studied. Two treatments (light and dark) were selected and the morphological structure of sweet corn sprouts, as well as their biochemical composition were investigated to determine the effects of light on the regulation of genes responsible for nutritional compounds. Transcription analyses for three key-encoding genes in the biosynthesis of the precursors of phenolic were studied. Results revealed a negative regulation in the expression of ZmPAL with total phenolic content (TPC) in the light group. TPC and total flavonoid content (TFC) increased during germination and this was correlated with an increase in antioxidant activity (r = 0.95 and 1.0). The findings illustrate that the nutritional value of sweet corn for the consumer can be improved through germination to the euphylla stage.


Assuntos
Flavonoides/metabolismo , Germinação , Luz , Fenóis/metabolismo , Zea mays/fisiologia , Antioxidantes/análise , Antioxidantes/metabolismo , Flavonoides/análise , Regulação da Expressão Gênica de Plantas , Fenóis/análise , Sementes/genética , Sementes/metabolismo , Sementes/fisiologia , Zea mays/química , Zea mays/genética , Zea mays/metabolismo
19.
Eur J Nucl Med Mol Imaging ; 43(4): 663-74, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26519293

RESUMO

PURPOSE: Small-cell cervical cancer (SCCC) is rare and prone to metastasize. We conducted a prospective study to evaluate the role of (18)F-FDG PET in the management of this aggressive malignancy. METHODS: Patients with untreated primary, histologically confirmed SCCC were enrolled. (18)F-FDG PET (or PET/CT) was performed immediately after MRI or CT, for primary staging, monitoring response to treatment or restaging when there was suspicion of recurrence. The clinical impact of PET was determined on a scan basis. RESULTS: A total of 25 patients were recruited and 43 PET scans were performed. The PET images were obtained for primary staging (25 patients), monitoring response (10 patients) and restaging when there was suspicion of recurrence (8 patients). The median follow-up time in event-free patients was 109.3 months (range 97.5 - 157.7 months). A positive impact of PET was found in 8 (18.6 %) of the 43 scans, which included detection of additional regions of distal lymph node (LN) metastasis (one primary staging scan, two restaging scans), bone metastasis (two primary staging scans, one monitoring response scan), and exclusion of false-positive lesions on MRI (one primary staging scan, one restaging scan). On the other hand, one negative impact was recorded as one false-positive lesion on a restaging PET scan. One positive impact was noted for monitoring response (bone metastasis). The impact of three scans was indeterminate. The positive impact of down-staging in avoiding overtreatment but finding additional distal LN (except one on restaging) or bone metastases had no beneficial effect on long-term survival. CONCLUSION: The results of this preliminary study suggest that PET is useful in the management of SCCC. PET could have more value in detecting occult metastases if future novel therapies are able to offer better control of extensive SCCC.


Assuntos
Carcinoma de Células Pequenas/diagnóstico por imagem , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Neoplasias do Colo do Útero/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Imagem Multimodal , Tomografia Computadorizada por Raios X
20.
Eur J Nucl Med Mol Imaging ; 43(10): 1812-23, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27160224

RESUMO

PURPOSE: The aim of this prospective study was to assess the usefulness of (18)F-FDG PET/CT performed before and during treatment for predicting treatment failure in patients with advanced squamous cell carcinoma of the uterine cervix treated with concurrent chemoradiotherapy (CCRT). METHODS: Patients with cervical squamous cell carcinoma, International Federation of Gynecology and Obstetrics stage III/IVA or positive pelvic or paraaortic lymph node (LN) metastasis without other distant metastasis on PET/CT entering a randomized trial of CCRT (AGOG 09-001) were eligible. PET/CT scans were performed at baseline, during week 3 of CCRT and 2 - 3 months after CCRT. PET/CT parameters were correlated with sites of failure and overall survival (OS). The resulting predictors developed from the study cohort were validated on two independent datasets using area under the curve values, sensitivities and specificities. RESULTS: With a median follow-up of 54 months for survivors, 20 (36 %) of the 55 eligible patients were proven to have treatment failure. Sites of failure were local in five, regional in 11, and distant in 11. Four predictors for local failure, three for regional failure, and four for distant failures were identified. After validation with two independent cohorts of 31 and 105 patients, we consider the following as clinically useful predictors: pretreatment metabolic tumour volume (MTV) and during-treatment cervical tumour MTV for local failure; during-treatment SUVnode (maximum standardized uptake value of LNs) for regional and distant failure, and during-treatment MTV for distant failure. During-treatment SUVnode (P = .001) and cervical tumour MTVratio (P = .004) were independent significant predictors of OS by stepwise Cox regression. CONCLUSION: PET/CT imaging before and during treatment is useful for predicting failure sites and OS, making tailored therapeutic modifications feasible with potential outcome improvement during primary therapy.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/terapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias Uterinas/diagnóstico por imagem , Neoplasias Uterinas/patologia , Neoplasias Uterinas/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Quimiorradioterapia , Feminino , Fluordesoxiglucose F18 , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
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