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1.
iScience ; 27(3): 109007, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38361632

RESUMO

Chromosomal instability (CIN) is a hallmark of cancers, and CIN-promoting mutations are not fully understood. Here, we report 141 chromosomal instability aiding variant (CIVa) candidates by assessing the prevalence of loss-of-function (LoF) variants in 135 chromosome segregation genes from over 150,000 humans. Unexpectedly, we observe both heterozygous and homozygous CIVa in Astrin and SKA3, two evolutionarily conserved kinetochore and microtubule-associated proteins essential for chromosome segregation. To stratify harmful versus harmless variants, we combine live-cell microscopy and controlled protein expression. We find the naturally occurring Astrin p.Q1012∗ variant is harmful as it fails to localize normally and induces chromosome misalignment and missegregation, in a dominant negative manner. In contrast, the Astrin p.L7Qfs∗21 variant generates a shorter isoform that localizes and functions normally, and the SKA3 p.Q70Kfs∗7 variant allows wild-type SKA complex localisation and function, revealing distinct resilience mechanisms that render these variants harmless. Thus, we present a scalable framework to predict and stratify naturally occurring CIVa, and provide insight into resilience mechanisms that compensate for naturally occurring CIVa.

2.
Nurs Open ; 10(10): 6856-6865, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37461183

RESUMO

AIM: In response to the ageing population and shortage of human resources for nursing care, China is piloting internet-based nursing services (nurses who provide this care are called online nurses). Nurses are the providers of this model, so it is important to understand their perceptions. We aim to explore nurses' perceptions of engaging in internet-based nursing services. DESIGN: This study is descriptive qualitative research, so the data were analysed using a descriptive qualitative research method based on the theory of planned behaviour, using thematic analysis. METHODS: With personal semi-structured interviews conducted by two Master of Science in Nursing with 18 online nurses and nine clinical nurses, terminated after information saturation. RESULTS: Nurses' emotional attitudes towards internet-based nursing services were generally positive, but their behavioural intentions were negative. Social support, hospital organisational climate and family responsibilities had a statistically significant impact on nurses' behavioural decisions. Internet-based nursing services place higher demands on nurses' knowledge and skills, and nurses are most concerned with ensuring patient and nurse safety. PATIENT OR PUBLIC CONTRIBUTION: No Patient or Public Contribution.


Assuntos
Enfermeiras e Enfermeiros , Serviços de Enfermagem , Humanos , Competência Clínica , Hospitais , China , Pesquisa Qualitativa
3.
Diagn Interv Radiol ; 29(2): 205-211, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36960636

RESUMO

PURPOSE: To explore the utility of four-phase computed tomography (CT) in distinguishing renal oncocytoma with central hypodense areas from clear cell renal cell carcinoma (ccRCC). METHODS: Eighteen patients with oncocytoma and 63 patients with ccRCC presenting with central hypodense areas were included in this study. All patients underwent four-phase CT imaging including the excretory phases later than 20 min after contrast injection. Two blinded experienced radiologists visually reviewed the enhancement features of the central hypodense areas in the excretory phase images and selected the area demonstrating the greatest degree of enhancement of the tumor in the corticomedullary phase images. Regions of interest (ROIs) were placed in the same location in each of the three contrast-enhanced imaging phases. Additionally, ROIs were placed in the adjacent normal renal cortex for normalization. The ratio of the lesion to cortex attenuation (L/C) for the three contrast-enhanced imaging phases and absolute de-enhancement were calculated. The receiver operating characteristic curve was used to obtain the cut-off values. RESULTS: Complete enhancement inversion of the central areas was observed in 12 oncocytomas (66.67%) and 16 ccRCCs (25.40%) (P = 0.003). Complete enhancement inversion combined with L/C in the corticomedullary phase lower than 1.0 (P < 0.001) or absolute de-enhancement lower than 42.5 HU (P < 0.001) provided 86.42% and 85.19% accuracy, 61.11% and 55.56% sensitivity, 93.65% and 93.65% specificity, 73.33% and 71.43% positive predictive value (PPV), and 89.39% and 88.06% negative predictive value (NPV), respectively, for the diagnosis of oncocytomas. Combined with complete enhancement inversion, L/C in the corticomedullary phase lower than 1.0 and absolute de-enhancement lower than 42.5 HU provided 87.65%, 55.56%, 96.83%, 83.33%, and 88.41% of accuracy, sensitivity, specificity, PPV, and NPV, respectively, for the diagnosis of oncocytomas. CONCLUSION: The combination of enhancement features of the central hypodense areas and the peripheral tumor parenchyma can help distinguish oncocytoma with central hypodense areas from ccRCC.


Assuntos
Adenoma Oxífilo , Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/patologia , Adenoma Oxífilo/diagnóstico por imagem , Adenoma Oxífilo/patologia , Meios de Contraste , Diagnóstico Diferencial , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Tomografia Computadorizada por Raios X/métodos , Diferenciação Celular , Estudos Retrospectivos
4.
Support Care Cancer ; 31(4): 214, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36918480

RESUMO

PURPOSE: Currently, the choice of contralateral prophylactic mastectomy (CPM) for breast cancer patients is variable and controversial. Breast cancer patients must make complex and rapid decisions based on the benefits and risks of CPM. Although there are many qualitative studies on the decision-making experiences of breast cancer patients, there is a lack of synthesis of these qualitative studies. Our study goals were to conduct a meta-synthesis of qualitative studies on the decision-making experiences, real-life experiences, psychological feelings and needs of breast cancer patients in CPM decision-making, with the aim of providing information to support the development of CPM practice decisions. METHODS: Using a meta-ethnographic approach, qualitative research studies were analysed and synthesised using the method of "reciprocal translational analysis", and themes related to the decision-making experiences of breast cancer patients with respect to CPM were identified. RESULTS: Five hundred ninety-three documents were retrieved. This meta-synthesis ultimately collected 8 studies. Four themes were identified: (1) decision motivations for survival and body intention; (2) negative and vacillating decision emotions; (3) diverse but weak decision support; (4) short-term satisfaction but long-term unknown and differentiated decision effects. CONCLUSIONS: We found that although patients had different feelings about the effects of CPM in detail, most patients were satisfied with the short-term effects of CPM, but the long-term effects of CPM were still unknown. The study protocol was registered with PROSPERO (International prospective register of systematic reviews) in May 2022 (Registration number: CRD42022334260).


Assuntos
Neoplasias da Mama , Mastectomia Profilática , Feminino , Humanos , Neoplasias da Mama/cirurgia , Neoplasias da Mama/psicologia , Tomada de Decisões , Mastectomia/psicologia , Mastectomia Profilática/psicologia , Pesquisa Qualitativa
5.
BMC Med Imaging ; 23(1): 16, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36707788

RESUMO

BACKGROUND: Although the central scar is an essential imaging characteristic of renal oncocytoma (RO), its utility in distinguishing RO from renal cell carcinoma (RCC) has not been well explored. The study aimed to evaluate whether the combination of CT characteristics of the peripheral tumor parenchyma (PTP) and central hypodense area (CHA) can differentiate typical RO with CHA from RCC. METHODS: A total of 132 tumors on the initial dataset were retrospectively evaluated using four-phase CT. The excretory phases were performed more than 20 min after the contrast injection. In corticomedullary phase (CMP) images, all tumors had CHAs. These tumors were categorized into RO (n = 23), clear cell RCC (ccRCC) (n = 85), and non-ccRCC (n = 24) groups. The differences in these qualitative and quantitative CT features of CHA and PTP between ROs and ccRCCs/non-ccRCCs were statistically examined. Logistic regression filters the main factors for separating ROs from ccRCCs/non-ccRCCs. The prediction models omitting and incorporating CHA features were constructed and evaluated, respectively. The effectiveness of the prediction models including CHA characteristics was then confirmed through a validation dataset (8 ROs, 35 ccRCCs, and 10 non-ccRCCs). RESULTS: The findings indicate that for differentiating ROs from ccRCCs and non-ccRCCs, prediction models with CHA characteristics surpassed models without CHA, with the corresponding areas under the curve (AUC) being 0.962 and 0.914 versus 0.952 and 0.839 respectively. In the prediction models that included CHA parameters, the relative enhancement ratio (RER) in CMP and enhancement inversion, as well as RER in nephrographic phase and enhancement inversion were the primary drivers for differentiating ROs from ccRCCs and non-ccRCCs, respectively. The prediction models with CHA characteristics had the comparable diagnostic ability on the validation dataset, with respective AUC values of 0.936 and 0.938 for differentiating ROs from ccRCCs and non-ccRCCs. CONCLUSION: The prediction models with CHA characteristics can help better differentiate typical ROs from RCCs. When a mass with CHA is discovered, particularly if RO is suspected, EP images with longer delay scanning periods should be acquired to evaluate the enhancement inversion characteristics of CHA.


Assuntos
Adenoma Oxífilo , Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/patologia , Adenoma Oxífilo/diagnóstico por imagem , Adenoma Oxífilo/patologia , Estudos Retrospectivos , Espécies Reativas de Oxigênio , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Tomografia Computadorizada por Raios X/métodos , Diagnóstico Diferencial
6.
Nurs Open ; 10(5): 2983-2990, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36528877

RESUMO

AIM: To summarize the whole process management measures for caregivers of inpatients in a non-new coronavirus pneumonia designated hospital in China during the novel coronavirus pneumonia epidemic. The implementation of these measures is mainly to prevent the virus pandemic caused by crowd gathering. DESIGN: A quasi-experimental study. METHODS: Novel coronavirus pneumonia prevention and control measures were implemented in the 'pre-hospital link, hospitalization link and discharge link' for the whole process of the hospitalized patients' caregivers. To evaluate the effects by time point inspection, the results were fed back using information technology for quality improvement. RESULTS: The results of three time point inspections indicated that the management quality of many projects improved continuously (p < 0.05). From January to June of 2021, 20 departments implemented a facial recognition information management system. The ratio of patients/caregivers admitted was 1:0.528~1:0.965; It was found that it is effective to implement the whole process management measures. The facial recognition system plays a key role in the comprehensive management of the caregivers.


Assuntos
COVID-19 , Humanos , Pandemias , Hospitais Gerais , Cuidadores , SARS-CoV-2 , Pacientes Internados
7.
Molecules ; 27(23)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36500294

RESUMO

Red ginseng (RG), which is obtained from heated Panax ginseng and is produced by steaming followed by drying, is a valuable herb in Asian countries. Steamed ginseng dew (SGD) is a by-product produced in processing red ginseng. In the present study, phytochemical profiling of extracts of red ginseng and steamed ginseng dew was carried out using gas chromatography-mass spectrometry (GC-MS) and rapid resolution liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (RRLC-Q-TOF-MS) analysis. Additionally, antioxidant activities (DPPH, ·OH, and ABTS scavenging ability) and whitening activities (tyrosinase and elastase inhibitory activity) were analyzed. Phytochemical profiling revealed the presence of 66 and 28 compounds that were non-saponin components in chloroform extracts of red ginseng and steamed ginseng dew (RG-CE and SGD-CE), respectively. Meanwhile, there were 20 ginsenosides identified in n-butanol extracts of red ginseng and steamed ginseng dew (RG-NBE and SGD-NBE). By comparing the different polar extracts of red ginseng and steamed ginseng dew, it was found that the ethyl acetate extract of red ginseng (RG-EAE) had the best antioxidant capacity and whitening effect, the water extract of steamed ginseng dew (SGD-WE) had stronger antioxidant capacity, and the SGD-NBE and SGD-CE had a better whitening effect. This study shows that RG and SGD have tremendous potential to be used in the cosmetic industries.


Assuntos
Cosméticos , Ginsenosídeos , Panax , Antioxidantes/farmacologia , Antioxidantes/análise , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Panax/química , Ginsenosídeos/química , Cosméticos/análise , Vapor
8.
Diagn Interv Radiol ; 28(6): 555-562, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36550755

RESUMO

PURPOSE We aimed to examine the usefulness of utilizing a specific contrast-enhanced computed tomog raphy (CT) region of interest (ROI) to differentiate renal oncocytoma (RO) from small clear cell renal cell carcinoma (ccRCC) and chromophobe renal cell carcinoma (chRCC). METHODS A retrospective analysis of pre-contrast phase (PCP), corticomedullary phase (CMP), and nephro graphic phase (NP) contrast-enhanced CT images of the histopathologically confirmed initial cohort (27 ROs, 74 ccRCCs, and 36 chRCCs) was conducted. Small, medium, large, and whole ROIs (S-ROI, M-ROI, L-ROI, and W-ROI, respectively) were utilized for CT attenuation value of tumor (AVT), lesion-to-cortex attenuation (L/C), and heterogeneous degree of tumor (HDT) calcula tions. Differences in these parameters were then compared between RO and ccRCC/chRCC, with receiver operating characteristic (ROC) curves being utilized to gauge the diagnostic utility of the statistically significant parameters. Logistic regression analyses were employed to identify key factors capable of differentiating RO and ccRCC/chRCC, with predictive models further being established. A validation cohort (6 ROs, 30 ccRCCs, and 12 chRCCs) was then employed to vali date the performance of the predictive models. RESULTS Of the parameters evaluated using different ROIs, L/C-CMP (S-ROI) (0.88 ± 0.15 vs. 1.13 ± 0.25, P < .001) and HDT-CMP (W-ROI) (23.02 (12.00-51.21) vs. 37.81 (16.09-89.45), P < .001) were best suited to differentiating RO and ccRCC, yielding respective area under the curve (AUC) values of 0.803 and 0.834. AVT-NP (S-ROI) (122.85 ± 18.87 vs. 86.50 ± 18.65, P < .001) and AVT-NP (M-ROI) (119 (86-167) vs. 81.5 (53-142), P < .001) were better able to differentiate RO and chRCC, yielding respective AUC values of 0.918 and 0.906. Logistic regression analyses revealed that L/C-CMP (S-ROI) and HDT-PCP, as well as AVT-NP (S-ROI) and HDT-CMP, were the primary factors capable of differentiating RO from ccRCC and chRCC, respectively. The predictive model developed to dif ferentiate between RO and ccRCC exhibited a sensitivity of 66.67% and 55.14% in the initial and validation cohorts, respectively, with corresponding specificity of 94.59% and 93.55%, accuracy of 87.13% and 86.84%, and AUC of 0.908 and 0.876. The predictive model developed to differ entiate between RO and chRCC exhibited a sensitivity of 85.19% and 100.00% in the initial and validation cohorts, respectively, with corresponding specificity of 94.59% and 92.86%, accuracy of 87.30% and 95.24%, and AUC of 0.944 and 0.959. CONCLUSION These data demonstrate that a combination of quantitative parameters measured with particu lar ROIs can enable the efficient and reliable differentiation of RO from ccRCC and chRCC for use in routine patient differential diagnosis.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/patologia , Estudos Retrospectivos , Espécies Reativas de Oxigênio , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Diagnóstico Diferencial , Tomografia Computadorizada por Raios X/métodos
9.
Front Bioeng Biotechnol ; 10: 958072, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992356

RESUMO

Postoperative intravesical instillation of chemotherapy is a routine procedure for non-muscular invasive bladder cancer (NMIBC). However, traditional bladder perfusion methods have insufficient exposure time, resulting in unsatisfactory therapeutic effects. In the present study, a chitosan (CS)-based in situ forming depot (ISFD) delivery system, including Fe3O4 magnetic nanoparticles (Fe3O4-MNP), CS, and ß-glycerophosphate (GP) as main components, was synthesized. Pirarubicin (THP), as a chemotherapeutic drug, was loaded into the new system. Results showed that our carrier system (Fe3O4-THP-CS/GP) was converted into gel and attached to the bladder wall, possessing loose network structures with magnetic targeting and sustained release properties. Moreover, its retention time in bladder was more than 72 h accompanied by a suitable expansion rate and good degradation characteristics. The antitumor activities of Fe3O4-THP-CS/GP were more effective both in vitro and in vivo than the free THP solution. In the study of its mechanism, results showed that Fe3O4-THP-CS/GP suppressed the expression of occludin (OCLN) and affected tight junctions (TJ) between urothelial cells to promote THP absorption.

10.
Nat Commun ; 12(1): 7010, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34853300

RESUMO

Defects in chromosome-microtubule attachment can cause chromosomal instability (CIN), frequently associated with infertility and aggressive cancers. Chromosome-microtubule attachment is mediated by a large macromolecular structure, the kinetochore. Sister kinetochores of each chromosome are pulled by microtubules from opposing spindle-poles, a state called biorientation which prevents chromosome missegregation. Kinetochore-microtubule attachments that lack the opposing-pull are detached by Aurora-B/Ipl1. It is unclear how mono-oriented attachments that precede biorientation are spared despite the lack of opposing-pull. Using an RNAi-screen, we uncover a unique role for the Astrin-SKAP complex in protecting mono-oriented attachments. We provide evidence of domains in the microtubule-end associated protein that sense changes specific to end-on kinetochore-microtubule attachments and assemble an outer-kinetochore crescent to stabilise attachments. We find that Astrin-PP1 and Cyclin-B-CDK1 pathways counteract each other to preserve mono-oriented attachments. Thus, CIN prevention pathways are not only surveying attachment defects but also actively recognising and stabilising mature attachments independent of biorientation.


Assuntos
Azul Alciano/metabolismo , Proteína Quinase CDC2/metabolismo , Segregação de Cromossomos , Ciclina B1/metabolismo , Cinetocoros/metabolismo , Microtúbulos , Receptores de Neuropeptídeo Y/metabolismo , Aurora Quinase B , Cromossomos , Instabilidade Genômica , Fenazinas , Fenotiazinas , Resorcinóis , Fuso Acromático , Polos do Fuso
11.
Br J Radiol ; 94(1120): 20200437, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33684313

RESUMO

OBJECTIVES: To investigate the feasibility of relative CT numbers to periappendiceal fat attenuation as an applicable index for estimating the severity of acute appendicitis. METHODS: In total, 308 consecutive surgery-confirmed acute appendicitis patients and 243 controls with available preoperative CT were analyzed retrospectively. The radiological parameters were appendix diameter, length, and wall thickness as concurrent appendicitis signs. CT numbers of periappendiceal fat, mesenteric fat, subcutaneous fat in the anterior and posterior abdominal wall, retroperitoneal fat, gluteal subcutaneous fat and psoas major muscle were measured, as well as the relative CT numbers of periappendiceal fat compared with other locations. RESULTS: There were 287 suppurative acute appendicitis (SAA) and 21 gangrenous or perforated acute appendicitis (GPAA) cases confirmed by pathology. The CT number of periappendiceal fat was significantly higher in patients than in controls (P<0.01) although there was a wide overlap (-72.33 HU-117.43 HU). Significant differences in relative CT numbers were observed between the groups in gluteal subcutaneous fat (RCTgl) and psoas major muscle (RCTps) (P<0.01). The AUCs of RCTgl and RCTps showed high accuracy to discriminate acute appendicitis from controls (AUC = 0.803, 0.761; 0.854, 0.847) and GPAA from SAA (AUC = 0.905, 0.851). CONCLUSIONS: Attenuation of periappendiceal fat on CT is related to the severity of appendicitis, and relative CT numbers (RCTgl and RCTps) could be an applicable index for severity determination. ADVANCES IN KNOWLEDGE: Periappendiceal fat infiltration is related to the severity of acute appendicitis (especially relative CT number). Other clinical and CT features also need to be considered in the evaluation of inflammation.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Apendicite/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Doença Aguda , Tecido Adiposo/patologia , Adulto , Apendicite/patologia , Apêndice/diagnóstico por imagem , Apêndice/patologia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Índice de Gravidade de Doença
12.
Exp Ther Med ; 16(4): 3041-3049, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30214523

RESUMO

Arecoline can be used to treat diseases including glaucoma and tapeworm infection, however, long-term administration can cause severe adverse effects, including oral submucosal fibrosis, oral cancer, hepatic injury and liver cancer. Autophagy serves a role in these injuries. The present study established a mouse model of arecoline-induced hepatic injury and investigated the role of autophagy-associated proteins in this injury. The results indicated that the expression levels of the autophagy marker protein microtubule associated protein 1 light chain 3 B (MAP1LC3B) and autophagy-promoting protein beclin 1 were elevated in the injured hepatic cells, while the expression levels of a well-known negative regulator of autophagy, mammalian target of rapamycin (mTOR), were reduced. Following treatment of the hepatic injury with glutathione, the liver function improved and liver damage was reduced effectively. Compared with the control group, the expression levels of both MAP1LC3B and beclin 1 were significantly upregulated in the glutathione-treated mice, but the expression of mTOR was significantly downregulated. It may be concluded that in the process of protecting against arecoline-induced hepatic injury, glutathione cooperates with mTOR and beclin 1 to accelerate autophagy, maintaining stable cell morphology and cellular functions.

13.
J Hazard Mater ; 343: 298-303, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-28988055

RESUMO

A phosphorylethanolamine-functionalized graphene foam (PNGF) has been proposed as an active filtration material for the capture and removal of heavy metal ions in water. Benefiting from its abundant hydrophilic portion of oxygen, nitrogen and phosphorus groups, the PNGF is super-hydrophilic. The selected heavy metal ions, Pb(II) and Cd(II), could be rapidly and efficiently absorbed within 10min using the PNGF through a filtration model, which is obviously less time compared with the several hours or even longer time when employing the traditional shaking or stirring model. In addition, the used PNGF filters can be easily reused after a simple, low-cost detachment using HCl to remove the heavy metals, providing a new approach for water purification.

14.
Chemistry ; 22(27): 9387-95, 2016 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-27249019

RESUMO

Graphitic carbon nitride nanodots (g-C3 N4 nanodots), as a new kind of heavy-metal-free quantum dots, have attracted considerable attention because of their unique physical and chemical properties. Although various methods to obtain g-C3 N4 nanodots have been reported, it is still a challenge to synthesize g-C3 N4 nanodots with ultrahigh fluorescence quantum yield (QY). In this study, highly fluorescent phosphorus/oxygen-doped graphitic carbon nitride (P,O-g-C3 N4 ) nanodots were prepared by chemical oxidation and hydrothermal etching of bulk P-g-C3 N4 derived from the pyrolysis of phytic acid and melamine. The as-prepared P,O-g-C3 N4 nanodots showed strong blue fluorescence and a relatively high QY of up to 90.2 %, which can be ascribed to intrinsic phosphorus/oxygen-containing groups, and surface-oxidation-related fluorescence enhancement. In addition, the P,O-g-C3 N4 nanodots were explored for cell imaging with excellent stability and biocompatibility, which suggest that they have great potential in biological applications.


Assuntos
Corantes Fluorescentes/química , Grafite/química , Nitrilas/química , Pontos Quânticos/química , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/metabolismo , Humanos , Células MCF-7 , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Oxirredução , Ácido Fítico/química , Pontos Quânticos/metabolismo , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Triazinas/química
15.
Angew Chem Int Ed Engl ; 55(12): 3936-41, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26890034

RESUMO

Surfaces with super-amphiphilicity have attracted tremendous interest for fundamental and applied research owing to their special affinity to both oil and water. It is generally believed that 3D graphenes are monoliths with strongly hydrophobic surfaces. Herein, we demonstrate the preparation of a 3D super-amphiphilic (that is, highly hydrophilic and oleophilic) graphene-based assembly in a single-step using phytic acid acting as both a gelator and as a dopant. The product shows both hydrophilic and oleophilic intelligence, and this overcomes the drawbacks of presently known hydrophobic 3D graphene assemblies. It can absorb water and oils alike. The utility of the new material was demonstrated by designing a heterogeneous catalytic system through incorporation of a zeolite into its amphiphilic 3D scaffold. The resulting bulk network was shown to enable efficient epoxidation of alkenes without prior addition of a co-solvent or stirring. This catalyst also can be recovered and re-used, thereby providing a clean catalytic process with simplified work-up.

16.
Anal Chim Acta ; 891: 261-8, 2015 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-26388385

RESUMO

In this work, europium-decorated graphene quantum dots (Eu-GQDs) were prepared by treating three-dimensional Eu-decorated graphene (3D Eu-graphene) via a strong acid treatment. Various characterizations revealed that Eu atoms were successfully complexed with the oxygen functional groups on the surface of graphene quantum dots (GQDs) with the atomic ratio of 2.54%. Compared with Eu free GQDs, the introduction of Eu atoms enhanced the electron density and improved the surface chemical activities of Eu-GQDs. Therefore, the obtained Eu-GQDs were used as a novel "off-on" fluorescent probe for the label-free determination of Cu(2+) and l-cysteine (L-Cys) with high sensitivity and selectivity. The fluorescence intensity of Eu-GQDs was quenched in the presence of Cu(2+) owing to the coordination reaction between Cu(2+) and carboxyl groups on the surface of the Eu-GQDs. The fluorescence intensity of Eu-GQDs recovered with the subsequent addition of L-Cys because of the strong affinity of Cu(2+) to L-Cys via the Cu-S bond. The experimental results showed that the fluorescence variation of the proposed approach had a good linear relationship in the range of 0.1-10 µM for Cu(2+) and 0.5-50 µM for L-Cys with corresponding detection limits of 0.056 µM for Cu(2+) and 0.31 µM for L-Cys. The current approach also displayed a special response to Cu(2+) and L-Cys over the other co-existing metal ions and amino acids, and the results obtained from buffer-diluted serum samples suggested its applicability in biological samples.


Assuntos
Cobre/análise , Cisteína/sangue , Európio/química , Corantes Fluorescentes/química , Grafite/química , Pontos Quânticos/química , Animais , Cátions Bivalentes/análise , Bovinos , Cisteína/análise , Humanos , Limite de Detecção , Modelos Moleculares , Pontos Quânticos/ultraestrutura , Espectrometria de Fluorescência/métodos
17.
Nanoscale ; 7(37): 15427-33, 2015 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-26335520

RESUMO

Highly fluorescent nitrogen-doped graphene quantum dots (N-GQDs) with greenish-yellow emission and quantum yield of 13.2% have been synthesized via a one-pot hydrothermal method. The obtained N-GQDs displayed excellent optical properties, high photostability and resistance to strong ion strength. Based on the higher affinity of pyrophosphate (PPi) than carboxyl and amido groups on the surface of the N-GQDs to Eu(3+), a Eu(3+)-modulated N-GQD off-on fluorescent probe for PPi detection was constructed with a detection limit of 0.074 µM. The detection process was simple in design, easy to operate, and showed a highly selective response to PPi in the presence of co-existing anions. This work widens the applications of N-GQDs with versatile functionality and reactivity in clinical diagnostics and as biosensors.


Assuntos
Difosfatos/análise , Európio/química , Corantes Fluorescentes/química , Grafite/química , Nitrogênio/química , Pontos Quânticos/química , Técnicas Biossensoriais , Cátions/química , Difosfatos/urina , Corantes Fluorescentes/síntese química , Humanos , Limite de Detecção
18.
BMJ Open ; 5(9): e008204, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26395497

RESUMO

OBJECTIVES: It remains unclear whether non-alcoholic fatty liver disease (NAFLD) is a cause or a consequence of metabolic syndrome (MetS). We proposed a simplified Bayesian network (BN) and attempted to confirm their reciprocal causality. SETTING: Bidirectional longitudinal cohorts (subcohorts A and B) were designed and followed up from 2005 to 2011 based on a large-scale health check-up in a Chinese population. PARTICIPANTS: Subcohort A (from NAFLD to MetS, n=8426) included the participants with or without NAFLD at baseline to follow-up the incidence of MetS, while subcohort B (from MetS to NAFLD, n=16,110) included the participants with or without MetS at baseline to follow-up the incidence of NAFLD. RESULTS: Incidence densities were 2.47 and 17.39 per 100 person-years in subcohorts A and B, respectively. Generalised estimating equation analyses demonstrated that NAFLD was a potential causal factor for MetS (relative risk, RR, 95% CI 5.23, 3.50 to 7.81), while MetS was also a factor for NAFLD (2.55, 2.23 to 2.92). A BN with 5 simplification strategies was used for the reciprocal causal inference. The BN's causal inference illustrated that the total effect of NAFLD on MetS (attributable risks, AR%) was 2.49%, while it was 19.92% for MetS on NAFLD. The total effect of NAFLD on MetS components was different, with dyslipidemia having the greatest (AR%, 10.15%), followed by obesity (7.63%), diabetes (3.90%) and hypertension (3.51%). Similar patterns were inferred for MetS components on NAFLD, with obesity having the greatest (16.37%) effect, followed by diabetes (10.85%), dyslipidemia (10.74%) and hypertension (7.36%). Furthermore, the most important causal pathway from NAFLD to MetS was that NAFLD led to elevated GGT, then to MetS components, while the dominant causal pathway from MetS to NAFLD began with dyslipidaemia. CONCLUSIONS: The findings suggest a reciprocal causality between NAFLD and MetS, and the effect of MetS on NAFLD is significantly greater than that of NAFLD on MetS.


Assuntos
Teorema de Bayes , Previsões , Síndrome Metabólica/complicações , Hepatopatia Gordurosa não Alcoólica/etiologia , Adulto , Glicemia/metabolismo , Índice de Massa Corporal , China/epidemiologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Incidência , Masculino , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Prevalência , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Ultrassonografia
19.
Anal Chim Acta ; 869: 89-95, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25818144

RESUMO

In this paper, the highly intrinsic peroxidase-like catalytic activity of nitrogen-doped graphene quantum dots (N-GQDs) is revealed. This activity was greatly dependent on pH, temperature and H2O2 concentration. The experimental results showed that the stable N-GQDs could be used for the detection of H2O2 and glucose over a wide range of pH and temperature, offering a simple, highly selective and sensitive approach for their colorimetric sensing. The linearity between the analyte concentration and absorption ranged from 20 to 1170 µM for H2O2 and 25 to 375 µM for glucose with a detection limit of 5.3 µM for H2O2 and 16 µM for glucose. This assay was also successfully applied to the detection of glucose concentrations in diluted serum and fruit juice samples.


Assuntos
Colorimetria/métodos , Glucose/análise , Grafite/química , Peróxido de Hidrogênio/análise , Nitrogênio/química , Peroxidase/metabolismo , Pontos Quânticos/química , Materiais Biomiméticos/química , Glicemia/análise , Catálise , Sucos de Frutas e Vegetais/análise , Concentração de Íons de Hidrogênio , Cinética , Limite de Detecção , Temperatura
20.
Biosens Bioelectron ; 68: 210-217, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25574860

RESUMO

Using graphitic carbon nitride (g-C3N4) nanosheets, an effective and facile fluorescence sensing approach for the label-free and selective determination of chromium (VI) (Cr(VI)) was developed. The fluorescence of the solution of g-C3N4 nanosheets was quenched effectively by Cr(VI) via the inner filter effect. Under optimal conditions, a wide detection linear range for Cr(VI) was found to be from 0.6 µM to 300 µM with a limit of detection (LOD) of 0.15 µM. In addition, the fluorescence of the solution of g-C3N4 nanosheets-Cr(VI) could be sensitively turned on in the presence of a reductant such as ascorbic acid (AA) via an "on-off-on" fluorescence response through the oxidation-reduction between Cr(VI) and AA. And a wide detection linear range for AA was found to be from 0.5 µM to 200 µM with an LOD of 0.13 µM. Furthermore, the proposed method has the potential application for detection of Cr(VI) in lake waters and AA in biological fluids.


Assuntos
Ácido Ascórbico/isolamento & purificação , Técnicas Biossensoriais , Cromo/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Ácido Ascórbico/química , Cromo/química , Fluorescência , Grafite/química , Humanos , Nanopartículas/química , Nitrilas/química , Poluentes Químicos da Água/química
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