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1.
Langmuir ; 40(17): 9280-9288, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38619299

RESUMO

Generally, for adhesive joints, the polar water molecules in humid environments can have a critical effect on the interfacial structures and structural evolution adjacent to the solid substrates. Regarding this, it is still a big challenge to detect and understand the interfacial hygrothermal aging process at the molecular level in real time and in situ. In this study, to trace the interfacial hygrothermal aging process of a classical epoxy formula containing diglycidyl ether of biphenyl A (DGEBA) and 2,2'-(ethylenedioxy) diethylamine (EDDA) with sapphire and fused silica in a typical hygrothermal environment (85 °C and 85% RH), sum frequency generation (SFG) vibrational spectroscopy was used to probe the molecular-level interfacial structural change over the time. The structural evolution dynamics at the buried epoxy/sapphire and epoxy/silica interfaces upon hygrothermal aging were revealed directly in situ. The interfacial delamination during hygrothermal aging was also elucidated from the molecular level. Upon hygrothermal aging, the interfacial CH signals, such as the ones from methyl, methylene, and phenyl groups, decreased significantly and the water OH signals increased substantially, indicating the water molecules had diffused into the interfaces and destroyed the original interactions between the epoxy formula and the substrates. Further analysis indicates that when the integrated signals in the CH range declined to their minimum and leveled off, the interfacial delamination happened. The tensile experiment proved the validity of these spectroscopic experimental results. Our study provides first-hand and molecular-level evidence on a direct correlation between the diffusion of the surrounding water molecules into the interface and the evolution/destruction of the interfacial structures during hygrothermal aging. More importantly, it is proved, SFG can be developed into a powerful tool to noninvasively reveal the local interfacial delamination in real time and in situ under extreme hygrothermal conditions, complemented by the mechanic test.

2.
Biomacromolecules ; 24(2): 967-976, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36607255

RESUMO

The development of nanoprobes that have amplified enhanced permeability and retention (EPR) effect is crucial for their precise cancer diagnosis performance. Here, we present the development of functional dendrimer-based nanogels (DNGs) with the generation three primary amine-terminated poly(amidoamine) (PAMAM) dendrimers (G3·NH2) cross-linked by N,N'-bis(acryloyl) cystamine (BAC). The DNGs were prepared through a Michael addition reaction between G3·NH2 dendrimers and BAC via an inverse microemulsion method and entrapped with gold nanoparticles (Au NPs) to form Au-DNGs. The Au-DNGs were sequentially modified with diethylenetriamine penta-acetic acid (DTPA)-gadolinium (Gd) complex, poly(ethylene glycol) (PEG)-linked arginine-glycine-aspartic (RGD) peptide, and 1,3-propanesultone (1,3-PS). The formed multifunctional RGD-Gd@Au-DNGs-PS (R-G@ADP) possessing an average diameter of 122 nm are colloidally stable and display a high X-ray attenuation coefficient, excellent r1 relaxivity (9.13 mM-1 s-1), desired protein resistance rendered by the zwitterionic modification, and cytocompatibility. With the targeting specificity mediated by RGD and the much better tumor penetration capability than the counterpart material of single dendrimer-entrapped Au NPs, the developed multifunctional R-G@ADP enable targeted and enhanced computed tomography (CT)/magnetic resonance (MR) dual-modal imaging of a pancreatic tumor model in vivo. The current work demonstrates a unique design of targeted and zwitterionic DNGs with prolonged blood circulation time as an emerging nanoprobe for specific tumor CT/MR imaging through amplified passive EPR effect.


Assuntos
Dendrímeros , Nanopartículas Metálicas , Neoplasias Pancreáticas , Humanos , Nanogéis , Ouro , Tomografia Computadorizada por Raios X/métodos , Imageamento por Ressonância Magnética/métodos , Oligopeptídeos , Espectroscopia de Ressonância Magnética , Linhagem Celular Tumoral
3.
World J Surg Oncol ; 20(1): 116, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35410225

RESUMO

BACKGROUND: Numerous case-control studies have reported associations between interleukin-17 (IL-17) polymorphisms and colorectal cancer; however, the results were inconsistent. The aim of this meta-analysis was to further clarify the effects of IL-17 polymorphisms on colorectal cancer susceptibility. MATERIALS AND METHOD: Relevant studies were extracted from the electronic databases PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), and the Chinese Biomedical Literature Database (CMB) up to April 2021. The odds ratio and 95% confidence interval were used to estimate the strength of the associations. RESULTS: Ten articles including 2599 cases and 2845 controls were enrolled in our research after strict literature screening. Highly significant associations between the IL-17A rs2275913 polymorphism and increased colorectal cancer susceptibility were observed in all five gene models (allelic, dominant, recessive, homozygous, and heterozygous models), and subgroup analysis based on ethnicity revealed that these associations existed not only in the Asian population but also in the Caucasian population. However, the results showed no significantly elevated colorectal cancer risk correlated with the IL-17F rs763780 polymorphism, and a slightly lower colorectal cancer susceptibility for the Caucasian population was discovered in the recessive and homozygous models of this mutation. CONCLUSION: The IL-17A rs2275913 polymorphism may be an independent risk factor contributing to colorectal cancer susceptibility, while the IL-17F rs763780 polymorphism may decrease susceptibility to colorectal cancer. Future studies with large-scale samples are warranted to identify these associations.


Assuntos
Neoplasias Colorretais , Interleucina-17 , Humanos , Estudos de Casos e Controles , Neoplasias Colorretais/genética , Predisposição Genética para Doença , Interleucina-17/genética , Polimorfismo de Nucleotídeo Único
4.
IEEE Sens J ; 22(24): 24493-24503, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37497077

RESUMO

A flexible fiber-coupled confocal laser endomicroscope has been developed using an electrostatic micro-electromechanical system (MEMS) scanner located in at distal optics to collect in vivo images in human subjects. Long transmission lines are required that deliver drive and sense signals with limited bandwidth. Phase shifts have been observed between orthogonal X and Y scanner axes from environmental perturbations, which impede image reconstruction. Image processing algorithms used for correction depend on image content and quality, while scanner calibration in the clinic can be limited by potential patient exposure to lasers. We demonstrate a capacitive sensing method to track the motion of the electrostatically driven two-dimensional MEMS scanner and to extract phase information needed for image reconstruction. This circuit uses an amplitude modulation envelope detection method on shared drive and sensing electrodes of the scanner. Circuit parameters were optimized for performance given high scan frequencies, transmission line effects, and substantial parasitic coupling of drive signal to circuit output. Extraction of phase information further leverages nonlinear dynamics of the MEMS scanner. The sensing circuit was verified by comparing with data from a position sensing detector measurement. The phase estimation showed an accuracy of 2.18° and 0.79° in X and Y axes for motion sensing, respectively. The results indicate that the sensing circuit can be implemented with feedback control for pre-calibration of the scanner in clinical MEMS-based imaging systems.

5.
Opt Lett ; 46(15): 3588-3591, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34329231

RESUMO

The dual-axis confocal (DAC) configuration provides a high axial resolution, long working distance (WD), and large dynamic range. These properties can reveal depth-resolved fluorescence spectra. We present a depth sensitive fluorescence spectroscopy based on the DAC configuration. The system enables high axial resolution of 3.23 µm and a long WD of 3.73 mm compared to that of 4.68 µm and 2.1 mm for comparable single-axis confocal configurations, respectively. Besides, a DAC configuration also offers a superior dynamic range and rejection of out-of-focus scattered light based on the principle of Huygens-Fresnel integrals. Additionally, to locate the target layer, the collection path of the DAC configuration will be used as the other illumination path, forming a dual-axis illumination configuration. These beam paths are used to locate the target layer using a white light imaging system with a commercial low numerical aperture objective. A multi-layer fluorescence phantom of Barrett's esophagus containing fluorescein isothiocyanate and Alexa Fluor 514 was used to verify the principle of depth-resolved fluorescence spectroscopy. The results show that the DAC configuration can collect fluorescence spectra from microscopic regions with high axial resolution.

6.
IEEE ASME Trans Mechatron ; 26(3): 1445-1454, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34295138

RESUMO

This paper applies image processing metrics to tracking of perturbations in mechanical phase delay in a multi-axis microelectromechanical system (MEMS) scanner. The compact mirror is designed to scan a laser beam in a Lissajous pattern during the collection of endoscopic confocal fluorescence images, but environmental perturbations to the mirror dynamics can lead to image registration errors and blurry images. A binarized, threshold-based blur metric and variance-based sharpness metric are introduced for detecting scanner phase delay. Accuracy of local optima of the metric for identification of phase delay is examined, and relative advantages for processing accuracy and computational complexity are assessed. Image reconstruction is demonstrated using both generic images and sample tissue images, with significant improvement in image quality for tissue imaging. Implications of non-ideal Lissajous scan effects on phase detection and image reconstruction are discussed.

7.
Bioconjug Chem ; 31(10): 2404-2412, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-33001643

RESUMO

Development of nanoplatforms for targeted anticancer drug delivery for effective tumor therapy still remains challenging in the development of nanomedicine. Here, we present a facile method to formulate a LAPONITE (LAP) nanodisk-based nanosystem for anticancer drug doxorubicin (DOX) delivery to folic acid (FA) receptor-overexpressing tumors. In the current work, aminated LAP nanodisks were first prepared through silanization, then functionalized with polyethylene glycol-linked FA (PEG-FA) via 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) chemistry, and finally employed to physically encapsulate DOX. The formed functional LAP nanodisks (for short, LM-PEG-FA) possess a high DOX loading efficiency (88.6 ± 1.2%) and present a pH-dependent release feature with a quicker DOX release under acidic pH conditions (pH 5.0) than under physiological pH conditions (pH 7.4). In vitro flow cytometry, confocal microscopic observation, and cell viability assay show that the LM-PEG-FA/DOX complexes can be specifically taken up by FAR-overexpressing human ovarian cancer cells (SK-OV-3 cells) and present a specific cancer cell therapeutic effect. Further tumor treatment results reveal that the LM-PEG-FA/DOX complexes can exert a specific therapeutic efficacy to a xenografted SK-OV-3 tumor model in vivo when compared with nontargeted LM-mPEG/DOX complexes. Therefore, the developed LM-PEG-FA nanodisks could be employed as a potential platform for targeted cancer chemotherapy.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Neoplasias Ovarianas/tratamento farmacológico , Animais , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Doxorrubicina/farmacocinética , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Feminino , Ácido Fólico/química , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanoestruturas/química , Neoplasias Ovarianas/patologia , Polietilenoglicóis/química
8.
IEEE ASME Trans Mechatron ; 25(2): 661-672, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33500606

RESUMO

We present a method to estimate high frequency rotary motion of a highly compact electrostatic micro-scanner using the same electrodes for both actuation and sensing. The accuracy of estimated rotary motion is critical for reducing blur and distortion in image reconstruction applications with the micro-scanner given its changing dynamics due to perturbations such as temperature. To overcome the limitation that no dedicated sensing electrodes are available in the proposed applications due to size constraints, the method adopts electromechanical amplitude modulation (EAM) to separate motion signal from parasitic capacitance feedthrough, and a novel non-linear measurement model is derived to characterize the relationship between large out-of-plane angular motion and circuit output. To estimate motion, an extended Kalman filter (EKF) and an unscented Kalman filter (UKF) are implemented, incorporating a process model based on the micro-scanner's parametric resonant dynamics and the measurement model. Experimental results show that compared to estimation without using the measurement model, our method is able to improve the rotary motion estimation accuracy of the micro-scanner significantly, with a reduction of root-mean-square error (RMSE) in phase shift of 86.1%, and a reduction of RMSE in angular position error of 78.5 %.

9.
J Cell Physiol ; 234(6): 9711-9722, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30370672

RESUMO

Ca2+ has been recognized as a key molecule for chondrocytes, however, the role and mechanism of spontaneous [Ca 2+ ] i signaling in cartilaginous extracellular matrix (ECM) metabolism regulation are unclear. Here we found that spontaneous Ca 2+ signal of in-situ porcine chondrocytes was [Ca 2+ ] o dependent, and mediated by [Ca 2+ ] i store release. T-type voltage-dependent calcium channel (T-VDCC) mediated [Ca 2+ ] o influx was associated with decreased cell viability and expression levels of ECM deposition genes. Further analysis revealed that chondrocytes expressed both inositol 1,4,5-trisphosphate receptor (InsP3R) and Orai isoforms. Inhibition of endoplasmic reticulum (ER) Ca 2+ release and store-operated calcium entry significantly abolished spontaneous [Ca 2+ ] i signaling of in-situ chondrocytes. Moreover, blocking ER Ca 2+ release with InsP3R inhibitors significantly upregulated ECM degradation enzymes production, and was accompanied by decreased proteoglycan and collagen type II intensity. Taken together, our data provided evidence that spontaneous [Ca 2+ ] i signaling of in-situ porcine chondrocytes was tightly regulated by [Ca 2+ ] o influx, InsP3Rs mediated [Ca 2+ ] i store release, and Orais mediated calcium release-activated calcium channels activation. Both T-VDCC mediated [Ca 2+ ] o influx and InsP3Rs mediated ER Ca 2+ release were found crucial to cartilaginous ECM metabolism through distinct regulatory mechanisms.


Assuntos
Sinalização do Cálcio , Cartilagem/metabolismo , Matriz Extracelular/metabolismo , Animais , Cálcio/metabolismo , Sobrevivência Celular , Células Cultivadas , Condrócitos/metabolismo , Retículo Endoplasmático/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Modelos Biológicos , Proteína ORAI1/metabolismo , Suínos
10.
J Exp Bot ; 70(2): 519-528, 2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30380101

RESUMO

Abscisic acid (ABA) plays a vital role in responses to abiotic stresses that allow plants to cope with environmental challenges. In this study, we analyzed ABA receptors of subfamily III as the potential targets of Cytosolic ABA Receptor Kinase 1 (CARK1). We previously found that CARK1 phosphorylated the subfamily III member RCAR11 at a distinct threonine residue (T78). Our study now shows the physical interaction of CARK1 with the receptors RCAR12/13/14 in vitro and in vivo. The catalytically inactive form CARK1-N204A did not interact with the receptors. Phosphorylation of these ABA receptors in vitro occurred at a serine/threonine amino acid residue corresponding to T78 in RCAR11, which is located in the loop of ß3 within a conserved site. Further analysis revealed that the phosphorylation of RCAR11T78 could increase the sensitivity of the pyr1pyl1pyl2pyl4 quadruple mutant (1124) to ABA, including the inhibition of root elongation and increasing drought tolerance. The analysis of CARK1:1124 complementation and the expression of ABA-related genes indicated that CARK1 could rescue the insensitivity of 1124 to ABA. Our results indicate that CARK1 tends to phosphorylate subfamily III ABA receptors, and the phosphosites RCAR11T78, RCAR12T105, RCAR13T101, and RCAR14S81 are the major sites involved in the activation of the ABA response pathway.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Arabidopsis , Regulação da Expressão Gênica de Plantas , Proteínas de Membrana Transportadoras/metabolismo , Fosforilação
11.
Acta Biochim Biophys Sin (Shanghai) ; 51(10): 1026-1033, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31553428

RESUMO

Ibuprofen, a medication in the nonsteroidal anti-inflammatory drug class, is widely used for treating inflammatory diseases such as osteoarthritis. It has been shown in recent years that ibuprofen has a strong effect on Ras homolog gene family, member A (RhoA) inhibition in multiple cell types. Our previous finding also demonstrated that interleukin-1ß (IL-1ß) increases filamentous actin (F-actin) of chondrocytes via RhoA pathway. Therefore, we hypothesized that ibuprofen may suppress the IL-1ß-induced F-actin upregulation in chondrocytes by inhibiting RhoA pathway. To this end, in this study, articular chondrocytes from New Zealand White rabbits were pretreated with 500 µM ibuprofen for 2 h, then with 10 ng/ml IL-1ß for 24 h. Results showed that pretreatment with ibuprofen inhibited the IL-1ß-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production, protected the chondrocyte phenotype from IL-1ß stimulation, and inhibited the IL-1ß-induced actin remodeling via RhoA signaling modulation. In conclusion, ibuprofen showed not only anti-inflammatory function, but also RhoA inhibition in articular chondrocytes.


Assuntos
Actinas/imunologia , Anti-Inflamatórios não Esteroides/farmacologia , Condrócitos/efeitos dos fármacos , Ibuprofeno/farmacologia , Interleucina-1beta/imunologia , Animais , Células Cultivadas , Condrócitos/imunologia , Condrócitos/patologia , Inflamação/tratamento farmacológico , Inflamação/imunologia , Inflamação/patologia , Coelhos , Proteína rhoA de Ligação ao GTP/imunologia
12.
J Pineal Res ; 64(2)2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29149494

RESUMO

Autophagy modulation is a potential therapeutic strategy for tongue squamous cell carcinoma (TSCC). Melatonin possesses significant anticarcinogenic activity. However, whether melatonin induces autophagy and its roles in cell death in TSCC are unclear. Herein, we show that melatonin induced significant apoptosis in the TSCC cell line Cal27. Apart from the induction of apoptosis, we demonstrated that melatonin-induced autophagic flux in Cal27 cells as evidenced by the formation of GFP-LC3 puncta, and the upregulation of LC3-II and downregulation of SQSTM1/P62. Moreover, pharmacological or genetic blockage of autophagy enhanced melatonin-induced apoptosis, indicating a cytoprotective role of autophagy in melatonin-treated Cal27 cells. Mechanistically, melatonin induced TFE3(Ser321) dephosphorylation, subsequently activated TFE3 nuclear translocation, and increased TFE3 reporter activity, which contributed to the expression of autophagy-related genes and lysosomal biogenesis. Luzindole, a melatonin membrane receptor blocker, or MT2-siRNA partially blocked the ability of melatonin to promote mTORC1/TFE3 signaling. Furthermore, we verified in a xenograft mouse model that melatonin with hydroxychloroquine or TFE3-siRNA exerted a synergistic antitumor effect by inhibiting autophagy. Importantly, TFE3 expression positively correlated with TSCC development and poor prognosis in patients. Collectively, we demonstrated that the melatonin-induced increase in TFE3-dependent autophagy is mediated through the melatonin membrane receptor in TSCC. These data also suggest that blocking melatonin membrane receptor-TFE3-dependent autophagy to enhance the activity of melatonin warrants further attention as a treatment strategy for TSCC.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/patologia , Melatonina/farmacologia , Neoplasias da Língua/patologia , Adulto , Idoso , Animais , Autofagia/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Receptor MT2 de Melatonina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Health Qual Life Outcomes ; 16(1): 138, 2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29996861

RESUMO

BACKGROUND: There have been very few studies analyzing the relationship of physical and mental health status with health behaviors and deployment status in Chinese navy personnel. Thus, we undertook this survey to assess this relationship and identify specific factors affecting the physical and mental health status. METHODS: The subjects enrolled in this study were selected from four units of the active-duty navy personnel in China, based on a cluster random sampling design. A total of 1200 Chinese navy personnel participated and completed the questionnaire survey that included veteran SF-36 form and a self-designed questionnaire regarding their sociodemographic characteristics, deployment status, self-rated health status and health behaviors. Totally 1200 questionnaires were distributed to different participants, while 1083 valid questionnaires were included in the final analysis. All data were analyzed using SPSS18.0 software. RESULTS: Based on the information provided by navy personnel, 17.82, 35.09 and 23.08% rated their health as excellent, very good and good, respectively. The mean score of physical component summary (PCS) and mental component summary (MCS) was 50.53 and 41.39, respectively. Length of service, binge drinking, regular drinking and BMI appeared to be associated with PCS score, while household income, binge drinking and BMI affected MCS score. Deployment status and smoking exhibited no significant association with PCS and MCS scores. CONCLUSIONS: Our study suggested that the sociodemographic factors like length of service and household income, along with behavioral risk factors like binge drinking, regular drinking and body mass index (BMI), seem to affect the physical and mental health status of Chinese navy personnel. However, additional data collection and more detailed analysis would still be required to develop a systematic, comprehensive and corresponding health education program to promote overall health status.


Assuntos
Nível de Saúde , Militares/psicologia , Veteranos/psicologia , Adulto , China , Estudos Transversais , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , Análise de Regressão , Fatores de Risco , Inquéritos e Questionários
14.
Int J Mol Sci ; 19(7)2018 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-30004422

RESUMO

The phytohormone abscisic acid (ABA) regulates plant growth, the developmental process, and abiotic stresses. ABA signaling is induced in response to mediate plant acclimation to environmental challenges, including high salinity and drought. The ABA-binding receptors (RCAR/PYR1/PYL), composing of 14 members, are the core components of the ABA-signaling pathway. Here, we observed that the three subfamilies within the RCARs showed different expression patterns at the basal and exogenous ABA levels. Subsequently, we generated transgenic plants overexpressing subfamily III, RCAR11⁻RCAR14, respectively. The transgenic plants showed increased ABA sensitivity in seed germination and post-germination seedling establishment and root length. Further studies revealed that the overexpressing subfamily III transgenic plants enhanced drought resistance, increased water-use efficiency, and accelerated stress-responsive gene expression compared with the wild-type plants. These findings confirm that the subfamily III plays a key role in ABA-mediated developmental processes and, more importantly, is involved in drought tolerance in the ABA-dependent pathway.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis , Arabidopsis , Germinação/genética , Proteínas de Membrana Transportadoras , Plantas Geneticamente Modificadas , Plântula , Ácido Abscísico/genética , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Desidratação , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plântula/genética , Plântula/crescimento & desenvolvimento
15.
Public Health Nutr ; 20(17): 3183-3192, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28980522

RESUMO

OBJECTIVE: To examine and quantify the potential dose-response relationship between green tea intake and the risk of gastric cancer. DESIGN: We searched PubMed, EMBASE, Web of Science, CBM, CNKI and VIP up to December 2015 without language restrictions. SETTING: A systematic review and dose-response meta-analysis of observational studies. SUBJECTS: Five cohort studies and eight case-control studies. RESULTS: Compared with the lowest level of green tea intake, the pooled relative risk (95 % CI) of gastric cancer was 1·05 (0·90, 1·21, I 2=20·3 %) for the cohort studies and the pooled OR (95 % CI) was 0·84 (0·74, 0·95, I 2=48·3 %) for the case-control studies. The pooled relative risk of gastric cancer was 0·79 (0·63, 0·97, I 2=63·8 %) for intake of 6 cups green tea/d, 0·59 (0·42, 0·82, I 2=1·0 %) for 25 years of green tea intake and 7·60 (1·67, 34·60, I 2=86·5 %) for drinking very hot green tea. CONCLUSIONS: Drinking green tea has a certain preventive effect on reducing the risk of gastric cancer, particularly for long-term and high-dose consumption. Drinking too high-temperature green tea may increase the risk of gastric cancer, but it is still unclear whether high-temperature green tea is a risk factor for gastric cancer. Further studies should be performed to obtain more detailed results, including other gastric cancer risk factors such as smoking and alcohol consumption and the dose of the effective components in green tea, to provide more reliable evidence-based medical references for the relationship between green tea and gastric cancer.


Assuntos
Neoplasias Gástricas/epidemiologia , Chá/efeitos adversos , Relação Dose-Resposta a Droga , Humanos , Internacionalidade , Estudos Observacionais como Assunto , Risco
16.
J Pineal Res ; 61(3): 353-69, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27396692

RESUMO

Cadmium (Cd), a highly ubiquitous heavy metal, induces neurotoxicity. Melatonin, a major secretory product of the pineal gland, protects against Cd-induced neurotoxicity. However, the mechanism that accounts for this protection remains to be elucidated. Herein, we exposed mouse neuroblastoma cells (Neuro-2a cells) to different concentrations of cadmium chloride (CdCl2 ) (12.5, 25, and 50 µ mol L(-1) ) for 24 hours. We showed that Cd inhibits autophagosome-lysosome fusion and impairs lysosomal function, subsequently leading to nerve cell death. In addition, Cd decreases the level of transcription factor EB (TFEB) but induces the nuclear translocation of TFEB, associated with compromised lysosomal function or a compensatory effect after the impairment of the autophagic flux. Moreover, compared to the 50-µ mol L(-1) Cd group, administration of 1 µ mol L(-1) melatonin increased "TFEB-responsive genes" (P<.05) and the levels of lysosomal-associated membrane protein (0.57±0.06 vs 1.00±0.11, P<.05), preserved lysosomal protease activity (0.52±0.01 vs 0.90±0.02, P<.05), maintained the lysosomal pH level (0.50±0.01 vs 0.87±0.05, P<.01), and enhanced autophagosome-lysosome fusion (0.05±0.00 vs 0.21±0.01, P<.01). Notably, melatonin enhanced TFEB expression (0.37±0.04 vs 0.72±0.07, P<.05) and nuclear translocation (2.81±0.08 vs 3.82±0.05, P<.05). Tfeb siRNA blocked the melatonin-mediated elevation in autophagy-lysosome machinery in Cd-induced neurotoxicity (P<.01). Taken together, these results uncover a potent role for TFEB-mediated autophagy in the pathogenesis of Cd-induced neurotoxicity, suggesting that control of the autophagic pathway by melatonin might provide an important clue for exploring potential targets for novel therapeutics of Cd-induced neurotoxicity.


Assuntos
Autofagia/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Cloreto de Cádmio/toxicidade , Núcleo Celular/metabolismo , Lisossomos/metabolismo , Melatonina/farmacologia , Proteínas de Neoplasias/metabolismo , Neuroblastoma/metabolismo , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Animais , Cádmio/toxicidade , Linhagem Celular Tumoral , Núcleo Celular/patologia , Camundongos , Neuroblastoma/patologia , Síndromes Neurotóxicas/tratamento farmacológico , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia
17.
Opt Lett ; 40(15): 3568-71, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26258359

RESUMO

In this Letter, photoacoustic-guided Raman spectroscopy (PARS) is proposed for a fast depth-resolved Raman measurement with accurate depth localization. The approach was experimentally demonstrated to receive both photoacoustic and Raman signals from a three-layer agar phantom based on a developed synergic photoacoustic-Raman probe, showing strong depth correlation and achieving magnitude of faster operation speed due to photoacoustic time-of-flight measurement and guidance, compared with the conventional depth-resolved Raman spectroscopy method. In addition, further combination with advanced optical-focusing techniques in biological-scattering medium could potentially enable the proposed approach for cancer diagnostics with both tight and fast optical focusing at the desired depth of tumor.

18.
Brain Sci ; 14(4)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38671994

RESUMO

Supervised classification algorithms for processing epileptic EEG signals rely heavily on the label information of the data, and existing supervised methods cannot effectively solve the problem of analyzing unlabeled epileptic EEG signals. In the traditional unsupervised clustering algorithm, the number of clusters and the global parameters must be predetermined, and the algorithm's analytical results are combined with a huge number of subjective errors, which affects the detection accuracy. For this reason, this paper proposes an unsupervised multivariate feature adaptive clustering analysis algorithm based on epileptic EEG signals. First, CEEMDAN and CWT are introduced into the epileptic EEG signal after preprocessing for joint denoising to further improve the signal quality. Then, the multivariate feature set of the signal is extracted and constructed, which includes nonlinear, time, frequency, and time-frequency characteristics. To reveal the hidden structures and correlations in the high-dimensional feature data, t-SNE dimensionality reduction is introduced. Finally, the DBSCAN clustering algorithm is optimized using the SSA algorithm to achieve adaptive selection of cluster number and global parameters.It not only enhances the clustering performance and reliability of the clustering results, but also avoids subjective errors in the analysis results. It provides a pre-theoretical foundation for the successful development of future seizure prediction devices and has good application prospects in clinical diagnosis and daily monitoring of patients.

19.
Microbiol Spectr ; 12(4): e0379723, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38483478

RESUMO

Hospital-acquired infections (HAIs) represent one of the significant causes of morbidity and mortality worldwide, and controlling pathogens in the hospital environment is of great importance. Currently, the standard disinfection method in the hospital environment is chemical disinfection. However, disinfectants are usually not used strictly according to the label, making them less effective in disinfection. Therefore, there is an emergent need to find a better approach that can be used in hospitals to control pathogenic bacteria in the clinical environment. Bacteriophages (phages) are effective in killing bacteria and have been applied in the treatment of bacterial infections but have not received enough attention regarding the control of contamination in the clinical environment. In this study, we found that various phages remain active in the presence of chemical disinfectants. Moreover, the combined use of specific phages and chemical disinfectants is more effective in removing bacterial biofilms and eliminating bacteria on hard surfaces. Thus, this proof-of-concept study indicates that adding phages directly to chemical disinfectants might be an effective and economical approach to enhance clinical environment disinfection. IMPORTANCE: In this study, we investigated whether the combination of bacteriophages and chemical disinfectants can enhance the efficacy of reducing bacterial contamination on hard surfaces in the clinical setting. We found that specific phages are active in chemical disinfectants and that the combined use of phages and chemical disinfectants was highly effective in reducing bacterial presence on hard surfaces. As a proof-of-concept, we demonstrated that adding specific phages directly to chemical disinfectants is an effective and cost-efficient strategy for clinical environment disinfection.


Assuntos
Bacteriófagos , Infecção Hospitalar , Desinfetantes , Humanos , Desinfetantes/farmacologia , Desinfecção/métodos , Bactérias
20.
Open Forum Infect Dis ; 11(2): ofad647, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38328500

RESUMO

Background: Pseudomonas aeruginosa is one of the most common pathogens in surgical site infections (SSIs). However, comprehensive epidemiological and antibiotic resistance details for P aeruginosa in Chinese SSIs are lacking. We evaluated the proportions and antimicrobial resistance of P aeruginosa among patients with SSIs in China. Methods: Relevant papers from January 2010 to August 2022 were searched in databases including PubMed, Embase, Web of Science, China Biomedical Literature Database, China National Knowledge Infrastructure, Wanfang, and Weipu. A meta-analysis was performed to analyze the proportions and 95% confidence interval (CIs) of P aeruginosa among patients with SSIs. Meta-regression analysis was used to investigate the proportion difference among different subgroups and antimicrobial resistance. Results: A total of 72 studies met inclusion criteria, involving 33 050 isolated strains. The overall proportion of P aeruginosa among patients with SSIs was 16.0% (95% CI, 13.9%-18.2%). Subgroup analysis showed higher proportions in orthopedic (18.3% [95% CI, 15.6%-21.0%]) and abdominal surgery (17.3% [95% CI, 9.9%-26.2%]). The proportion in the central region (18.6% [95% CI, 15.3%-22.1%]) was slightly higher than that in other regions. Antibiotic resistance rates significantly increased after 2015: cefoperazone (36.2%), ceftriaxone (38.9%), levofloxacin (20.5%), and aztreonam (24.0%). Notably, P aeruginosa resistance to ampicillin and cefazolin exceeded 90.0%. Conclusions: The proportion of P aeruginosa infection among patients with SSIs was higher than the data reported by the Chinese Antimicrobial Resistance Surveillance System, indicating rising antimicrobial resistance. The existing antimicrobial drug management plan should be strengthened to prevent a hospital epidemic of drug-resistant P aeruginosa strains.

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