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1.
PLoS Biol ; 21(3): e3002033, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36928253

RESUMO

Aging is a systemic process, which is a risk factor for impaired physiological functions, and finally death. The molecular mechanisms driving aging process and the associated cognitive decline are not fully understood. The hypothalamus acts as the arbiter that orchestrates systemic aging through neuroinflammatory signaling. Our recent findings revealed that Menin plays important roles in neuroinflammation and brain development. Here, we found that the hypothalamic Menin signaling diminished in aged mice, which correlates with systemic aging and cognitive deficits. Restoring Menin expression in ventromedial nucleus of hypothalamus (VMH) of aged mice extended lifespan, improved learning and memory, and ameliorated aging biomarkers, while inhibiting Menin in VMH of middle-aged mice induced premature aging and accelerated cognitive decline. We further found that Menin epigenetically regulates neuroinflammatory and metabolic pathways, including D-serine metabolism. Aging-associated Menin reduction led to impaired D-serine release by VMH-hippocampus neural circuit, while D-serine supplement rescued cognitive decline in aged mice. Collectively, VMH Menin serves as a key regulator of systemic aging and aging-related cognitive decline.


Assuntos
Envelhecimento , Disfunção Cognitiva , Hipotálamo , Animais , Camundongos , Envelhecimento/genética , Envelhecimento/metabolismo , Disfunção Cognitiva/genética , Disfunção Cognitiva/metabolismo , Hipotálamo/metabolismo , Serina/metabolismo , Fatores de Transcrição/metabolismo
2.
Molecules ; 29(8)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38675699

RESUMO

In the face of ongoing water pollution challenges, the intricate interplay between dissolved organic matter and disinfectants like chlorine gives rise to potentially harmful disinfection byproducts (DBPs) during water treatment. The exploration of DBP formation originating from amino acids (AA) is a critical focus of global research. Aromatic DBPs, in particular, have garnered considerable attention due to their markedly higher toxicity compared to their aliphatic counterparts. This work seeks to advance the understanding of DBP formation by investigating chlorination disinfection and kinetics using tyrosine (Tyr), phenylalanine (Phe), and tryptophan (Trp) as precursors. Via rigorous experiments, a total of 15 distinct DBPs with accurate molecular structures were successfully identified. The chlorination of all three AAs yielded highly toxic chlorophenylacetonitriles (CPANs), and the disinfectant dosage and pH value of the reaction system potentially influence chlorination kinetics. Notably, Phe exhibited the highest degradation rate compared to Tyr and Trp, at both the CAA:CHOCl ratio of within 1:2 and a wide pH range (6.0 to 9.0). Additionally, a neutral pH environment triggered the maximal reaction rates of the three AAs, while an acidic condition may reduce their reactivity. Overall, this study aims to augment the DBP database and foster a deeper comprehension of the DBP formation and relevant kinetics underlying the chlorination of aromatic AAs.


Assuntos
Aminoácidos Aromáticos , Desinfecção , Halogenação , Purificação da Água , Cinética , Aminoácidos Aromáticos/química , Purificação da Água/métodos , Desinfetantes/química , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio
3.
Molecules ; 29(2)2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38257310

RESUMO

The unrestricted utilization of antibiotics poses a critical challenge to global public health and safety. Levofloxacin (LEV) and sulfaphenazole (SPN), widely employed broad-spectrum antimicrobials, are frequently detected at the terminal stage of water treatment, raising concerns regarding their potential conversion into detrimental disinfection byproducts (DBPs). However, current knowledge is deficient in identifying the potential DBPs and elucidating the precise transformation pathways and influencing factors during the chloramine disinfection process of these two antibiotics. This study conducts a comprehensive analysis of reaction pathways, encompassing piperazine ring opening/oxidation, Cl-substitution, OH-substitution, desulfurization, and S-N bond cleavage, during chloramine disinfection. Twelve new DBPs were identified in this study, exhibiting stability and persistence even after 24 h of disinfection. Additionally, an examination of DBP generation under varying disinfectant concentrations and pH values revealed peak levels at a molar ratio of 25 for LEV and SPN to chloramine, with LEV contributing 11.5% and SPN 23.8% to the relative abundance of DBPs. Remarkably, this research underscores a substantial increase in DBP formation within the molar ratio range of 1:1 to 1:10 compared to 1:10 to 1:25. Furthermore, a pronounced elevation in DBP generation was observed in the pH range of 7 to 8. These findings present critical insights into the impact of the disinfection process on these antibiotics, emphasizing the innovation and significance of this research in assessing associated health risks.


Assuntos
Levofloxacino , Purificação da Água , Levofloxacino/farmacologia , Sulfafenazol , Cloraminas/farmacologia , Desinfecção , Antibacterianos/farmacologia
4.
Opt Express ; 31(12): 19453-19462, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381360

RESUMO

To accurately measure the local temperatures of the micro-nano area, we propose an optical method using a tapered fiber Bragg grating (FBG) probe with a nano tip for scanning probe microscopy (SPM). When the tapered FBG probe senses local temperature through near-field heat transfer, the intensity of the reflected spectrum decreases, along with a broadening bandwidth and a shift in the central peak position. Modeling the heat transfer between the probe and the sample shows that the tapered FBG probe is in a non-uniform temperature field when approaching the sample surface. Simulation of the probe's reflection spectrum reveals that the central peak position shifts nonlinearly with increasing local temperature. In addition, the near-field temperature calibration experiments show that the temperature sensitivity of the FBG probe increases nonlinearly from 6.2 pm/°C to 9.4 pm/°C as the sample surface temperature increases from 25.3°C to 160.4°C. The agreement of the experimental results with the theory and the reproducibility demonstrate that this method offers a promising approach for exploring micro-nano temperature.

5.
Appl Opt ; 62(13): 3275-3283, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37132827

RESUMO

In order to efficiently select the optimal cutting position of x-ray mono-capillary lenses, an improved sine cosine algorithm-crow search algorithm (SCA-CSA) algorithm is proposed, which combines the sine cosine algorithm with the crow search algorithm, with further enhancements. The fabricated capillary profile is measured using an optical profiler; then the surface figure error for interest regions of the mono-capillary can be evaluated using the improved SCA-CSA algorithm. The experimental results indicate that the surface figure error in the final capillary cut region is about 0.138 µm, and the runtime is 2.284 s. When compared with the traditional metaheuristic algorithm, the particle swarm optimization algorithm, the improved SCA-CSA algorithm, enhances the surface figure error metric by two orders of magnitude. Furthermore, the standard deviation index of the surface figure error metric for 30 runs also improves by more than 10 orders of magnitude, demonstrating the superior performance and robustness of the algorithm. The proposed method provides significant support for the development of precise cuttings of mono-capillaries.

6.
Opt Express ; 30(10): 16606-16618, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-36221499

RESUMO

In this study, a sapphire-derived fiber (SDF)-based Fabry-Pérot interferometer (FPI) is proposed and experimentally demonstrated as a high-temperature sensor using the arc discharge crystallization process, forming a region with disordered mullite grains. This shows that the disordered mullite grains are related to the gradual temperature distribution during the arc discharge process, which results in a larger refractive index (RI) modulation of the SDF near the fusing area, forming a reflection mirror. An FPI was obtained by combining the optical fiber end facet. Considering the high-temperature resistance of the fiber, the fabricated FPI was used for high-temperature sensing. This shows that the device can operate at temperatures of up to 1200 °C with a sensitivity of 15.47 pm/°C, demonstrating that the proposed devices have potential applications in high-temperature environments.

7.
Sensors (Basel) ; 22(13)2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35808238

RESUMO

In recent years, the use of Artificial Intelligence for emotion recognition has attracted much attention. The industrial applicability of emotion recognition is quite comprehensive and has good development potential. This research uses voice emotion recognition technology to apply it to Chinese speech emotion recognition. The main purpose of this research is to transform gradually popularized smart home voice assistants or AI system service robots from a touch-sensitive interface to a voice operation. This research proposed a specifically designed Deep Neural Network (DNN) model to develop a Chinese speech emotion recognition system. In this research, 29 acoustic characteristics in acoustic theory are used as the training attributes of the proposed model. This research also proposes a variety of audio adjustment methods to amplify datasets and enhance training accuracy, including waveform adjustment, pitch adjustment, and pre-emphasize. This study achieved an average emotion recognition accuracy of 88.9% in the CASIA Chinese sentiment corpus. The results show that the deep learning model and audio adjustment method proposed in this study can effectively identify the emotions of Chinese short sentences and can be applied to Chinese voice assistants or integrated with other dialogue applications.


Assuntos
Inteligência Artificial , Fala , Acústica , China , Emoções , Redes Neurais de Computação
8.
Molecules ; 27(21)2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36364435

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) and their oxygen/nitrogen derivatives released into the atmosphere can alternate between a gas phase and a particulate phase, further affecting their environmental behavior and fate. The gas/particulate partition coefficient (KP) is generally used to characterize such partitioning equilibrium. In this study, the correlation between log KP of fifty PAH derivatives and their n-octanol/air partition coefficient (log KOA) was first analyzed, yielding a strong linear correlation (R2 = 0.801). Then, Gaussian 09 software was used to calculate quantum chemical descriptors of all chemicals at M062X/6-311+G (d,p) level. Both stepwise multiple linear regression (MLR) and support vector machine (SVM) methods were used to develop the quantitative structure-property relationship (QSPR) prediction models of log KP. They yield better statistical performance (R2 > 0.847, RMSE < 0.584) than the log KOA model. Simulation external validation and cross validation were further used to characterize the fitting performance, predictive ability, and robustness of the models. The mechanism analysis shows intermolecular dispersion interaction and hydrogen bonding as the main factors to dominate the distribution of PAH derivatives between the gas phase and particulate phase. The developed models can be used to predict log KP values of other PAH derivatives in the application domain, providing basic data for their ecological risk assessment.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Hidrocarbonetos Policíclicos Aromáticos/análise , Nitrogênio/análise , Oxigênio/análise , Atmosfera/química , 1-Octanol , Poeira/análise
9.
Opt Express ; 29(15): 24289-24299, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34614677

RESUMO

We have proposed and experimentally demonstrated a sapphire-derived fiber (SDF) and silica capillary-based compound Fabry-Pérot interferometer (FPI) for high-pressure and high-temperature sensing. The SDF owns high alumina dopant concentration core, which can generate a mullite crystallization region during an arc discharge process. The crystallization region acts as a reflective interface to form one FPI in the SDF. The other FPI contains an air cavity constructed by the silica capillary and is used for high-pressure sensing. Both gas pressure within a range from 0 MPa to 4 MPa and temperature within a range from 20°C to 700°C are measured. Experimental results show that the wavelength shift of the FPI versus the applied pressure is linear at each tested temperature. The pressure sensitivity is measured to be 5.19 nm/MPa at a high temperature of 700°C, and the linear responses show excellent repeatability with linearity of 0.999. Meanwhile, the proposed FPI can stably function at a high temperature of 700°C with a temperature sensitivity of 0.013 nm/°C. The proposed FPI sensor provides a promising candidate for simultaneous measurement of high pressure and high temperature in extreme conditions.

10.
Opt Express ; 29(21): 34577-34589, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34809244

RESUMO

The magneto-refractive properties of an erbium-doped fiber (EDF) are investigated by theoretically analyzing the change in mode characteristics with a magnetic field and experimentally measuring it based on a fiber-optic Mach-Zehnder interferometer (MZI). The numerical results indicate that the mode effective refractive index (RI) increases as the magnetic field increases, and the mode field intensity distribution tends to be more concentrated in the core region with an increasing magnetic field. The variation in the mode effective RI of the fundamental mode with the magnetic field is greater than that of the higher-order modes. A magneto-refractive measurement system based on a fiber-optic MZI is set up to analyze the magneto-refractive effect of the EDF. The changes in the mode effective RI measured with a direct-current (DC) magnetic field and with a 100 Hz alternating-current (AC) magnetic field are 4.838×10-6 and 4.245×10-6 RIU/mT, respectively. The experimental results are in reasonable agreement with the theoretical analysis. Furthermore, the error between the experimental and numerical results is discussed. The magneto-refractive properties of the EDF exhibit potential in all-fiber magnetic field or current sensing area.

11.
Microvasc Res ; 130: 104011, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32371104

RESUMO

To assess the microcirculation in a patient's capillaries, clinicians often use the valuable and non-invasive diagnostic tool of nailfold capillaroscopy (NC). In particular, evaluating the images that result from NC is particularly important for diagnosing diseases in which the capillary morphology is altered. However, NC images are generally of poor quality, such that analyzing them is difficult and time consuming. Thus, the purpose of this work was to determine a way to segment the capillaries in poor-quality NC images accurately. To do this, we proposed using a deep neural network with a Res-Unet structure. The network combines the residual network (ResNet) and the U-Net to establish an encoding-decoding network and to deepen the layers in the network to preserve the features of the deep layer. The network was trained on 30 nailfold capillary images to discriminate the pixels belonging to capillaries, and it was then tested on a dataset consisting of 20 images to achieve a binarized map. The mean accuracy was 91.72% and the mean Dice score was 97.66% compared to the ground truth, which indicates that using Res-Unet to perform capillary segmentation in NC images had good performance.


Assuntos
Capilares/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador , Angioscopia Microscópica , Unhas/irrigação sanguínea , Redes Neurais de Computação , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Adulto Jovem
12.
Med Sci Monit ; 26: e921618, 2020 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-32417847

RESUMO

BACKGROUND Intestinal ischemia-reperfusion injury is a serious intestinal disease, with main symptoms of inflammatory reaction and severe oxidative damage. In addition, GTS-21-induced alpha7 nAChR has been shown to exert anti-inflammatory effects and anti-oxidation effects in various organs. However, whether alpha7 nAChR can alleviate ischemia-reperfusion-induced intestinal injury is unclear. MATERIAL AND METHODS We used intestinal epithelial cells (IEC-6) to perform the experiments. Oxygen glucose deprivation/reoxygenation (OGD/R) was used to simulate the physiological environment of ischemia-reperfusion. First, the expression of alpha7 nAChR was determined in these cells which was cultured under OGD/R conditions. After that, the GTS-21 was used to treat these cells and the levels of inflammatory factors (TNF-alpha, IL-1ß, IL-6, and IL-10) were assessed by ELISA. Next, the levels of ROS, SOD, and MDA were determined in IEC-6 cells. Finally, the apoptosis rates of IEC-6 cells were measured by flow cytometry. RESULTS Results showed that the expression of TNF-alpha, IL-1ß, and IL-6 was enhanced when the IEC-6 cells were cultured under OGD/R conditions. However, after treatment with GTS-21, the levels of these proinflammatory factors were suppressed. In addition, the levels of ROS and MDA were also inhibited and the expression of SOD was promoted after GTS-21 treatment. We also found that the ratios of apoptotic cells declined after GTS-21 treatment. CONCLUSIONS GTS-21-induced alpha7 nAChR decreased the OGD/R-induced inflammatory response, oxidative damage, and apoptosis of intestinal epithelial cells.


Assuntos
Compostos de Benzilideno/farmacologia , Piridinas/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Apoptose/efeitos dos fármacos , Compostos de Benzilideno/metabolismo , Linhagem Celular , Citocinas/metabolismo , Enterócitos/patologia , Glucose/metabolismo , Humanos , Inflamação/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/fisiologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxigênio/metabolismo , Piridinas/metabolismo , Reperfusão/métodos , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/efeitos dos fármacos
13.
Opt Express ; 27(26): 37900-37909, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31878563

RESUMO

We investigate the microstructural characteristics and optical properties of PbS quantum dots-doped silica fiber (PQDF), prepared by atomic layer deposition (ALD) doping technique. The fiber exhibits ultra-wideband luminescence and flat-gain with 3 dB bandwidth of 300 nm. The on-off gain and net gain can reach to 7.1-15.0 dB and 6.0-9.2 dB at 1050-1350 nm, respectively. The results of high-resolution transmission electron microscopy (HRTEM) further reveal the effects of PbS QDs doping in PQDF. The broadband luminescence spectrum originating from three active centers (1086, 1179, and 1304 nm), can be attributed to the dimension effect of PbS QDs (3.7, 4.0, and 4.3 nm, respectively). Moreover, the calculation results indicate that the multi-sized PbS QDs concentrated at 3.65-4.45 nm make the 3 dB gain bandwidth increase, which is six times wider than that of traditional erbium-doped fiber (EDF). Therefore, this type of PQDF is a promising gain medium for optical amplifiers and broadband light sources.

14.
Eur J Nutr ; 57(8): 2701-2712, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28942514

RESUMO

PURPOSE: Gestational diabetes is associated with increased risk to the health of the mother and her offspring. In particular, the infants of diabetic mothers (IDMs) exhibit elevated levels of preterm birth, macrosomia, hypoglycemia, hypocalcemia, and cardiomyopathy. We have previously reported that IDMs showed abnormalities in cardiac Akt-related insulin signalling, and that these deficiencies in Akt-related signalling were attenuated by supplementing the maternal diet with fish-oil. Herein, we investigated whether the eicosapentaenoic acid (EPA) found in fish oil can be used to attenuate diabetes associated impairments in cardiomyocyte signalling. METHODS: Pregnant diabetic rats were administered streptozotocin before receiving EPA or water, and their infants were designated IDM/EPA, IDM/W. We assessed the potential molecular pathway for this effect in the primary cardiac cell from newborn rat hearts. RESULTS: Insulin resistance as determined by diminished GLUT4 translocation following insulin stimulation, the levels of advanced glycation end products (AGEs) and reactive oxygen species were elevated in the neonatal hearts of IDM/W compared with that seen in the offspring born from non-diabetic control animals. Similarly, the receptor of AGEs (RAGE) mRNA levels, reactive oxygen species and the amount of nuclear factor-κB (NF-κB), tumor necrosis factor-α (TNF-α), and interleukin 6 (IL-6) mRNA were higher in the hearts from the IDM/W when compared to that observed in the hearts of offspring born to non-diabetic animals. These deleterious effects of gestational diabetes were significantly decreased in the offspring of diabetic mothers receiving EPA supplementation. CONCLUSIONS: Taken together, our data suggest that the EPA in fish oil may improve the impaired signalling and the excessive protein glycation in the cardiac muscles of infants exposed to intrauterine hyperglycemia.


Assuntos
Animais Recém-Nascidos , Diabetes Mellitus Experimental/metabolismo , Hiperglicemia/tratamento farmacológico , Miocárdio/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Gestacional/tratamento farmacológico , Ácido Eicosapentaenoico/farmacologia , Feminino , Óleos de Peixe/farmacologia , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Gravidez , Ratos , Espécies Reativas de Oxigênio/metabolismo , Receptor para Produtos Finais de Glicação Avançada/genética , Transdução de Sinais , Triglicerídeos/sangue , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
15.
J Cardiovasc Pharmacol ; 70(4): 225-231, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28582278

RESUMO

Mesenchymal stem cells (MSCs) and their secreted exosomes exert a cardioprotective role in jeopardized myocardium. However, the specific effects and underlying mechanisms of exosomes derived from adipose-derived MSCs (ADMSCs) on myocardial ischemia/reperfusion (I/R) injury remain largely unclear. In this study, ADMSC-derived exosomes (ADMSCs-ex) were administrated into the rats subjected to I/R injury and H9c2 cells exposed to hypoxia/reoxygenation (H/R). Consequently, administration of ADMSCs-ex significantly reduced I/R-induced myocardial infarction, accompanied with a decrease in serum levels of creatine kinase-myocardial band, lactate dehydrogenase, and cardiac troponin I (cTnI). Simultaneously, ADMSCs-ex dramatically antagonized I/R-induced myocardial apoptosis, along with the upregulation of Bcl-2 and downregulation of Bax, and inhibition of Caspase 3 activity in rat myocardium. Similarly, ADMSCs-ex significantly reduced cell apoptosis and the expression of Bax, but markedly increased cell viability and the expression of Bcl-2 and Cyclin D1 under H/R. Furthermore, ADMSCs-ex observably induced the activation of Wnt/ß-catenin signaling by attenuating I/R- and H/R-induced inhibition of Wnt3a, p-GSK-3ß (Ser9), and ß-catenin expression. Importantly, treatment with Wnt/ß-catenin inhibitor XAV939 partly neutralized ADMSC-ex-induced antiapoptotic and prosurvival effects in H9c2 cells. In conclusion, we confirmed that ADMSCs-ex protect ischemic myocardium from I/R injury through the activation of Wnt/ß-catenin signaling pathway.


Assuntos
Tecido Adiposo/transplante , Exossomos/transplante , Células-Tronco Mesenquimais/fisiologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Via de Sinalização Wnt/fisiologia , Animais , Linhagem Celular , Sobrevivência Celular/fisiologia , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Miocárdio/patologia , Ratos , Ratos Sprague-Dawley
16.
Nanomedicine ; 13(3): 1051-1059, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27979746

RESUMO

Surface-enhanced Raman spectroscopy (SERS) involving expressed prostatic secretion (EPS) and serum was investigated; the objective was to determine if this approach could distinguish prostate cancer from benign prostatic hyperplasia. A total of 120 SERS spectra for EPS and 96 spectra for serum were gathered from patients within a prospective contemporary biopsy cohort. Significant differences in spectra between prostate cancer and benign prostatic hyperplasia were tentatively assigned to component changes in EPS and serum samples. Principal component analysis and linear discriminate analysis were utilized to evaluate the spectral data for EPS and serum, to build diagnostic algorithms. The leave-one-out cross-validation method was used to validate the diagnostic algorithms; it revealed diagnostic sensitivities of 75% and 60%, specificities of 75% and 76.5%, and accuracies of 75% and 68% for EPS and serum, respectively. The results suggest that EPS and serum SERS analysis could be a potential tool for prostate cancer detection.


Assuntos
Próstata/patologia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico , Análise Espectral Raman/métodos , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Componente Principal , Estudos Prospectivos , Neoplasias da Próstata/patologia , Sensibilidade e Especificidade
17.
Sensors (Basel) ; 17(3)2017 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-28245618

RESUMO

A taper-fiber SERS nanoprobe modified by gold nanoparticles (Au-NPs) with ultrathin alumina layers was fabricated and its ability to perform remote Raman detection was demonstrated. The taper-fiber nanoprobe (TFNP) with a nanoscale tip size under 80 nm was made by heated pulling combined with the chemical etching method. The Au-NPs were deposited on the TFNP surface with the electrostatic self-assembly technology, and then the TFNP was wrapped with ultrathin alumina layers by the atomic layer deposition (ALD) technique. The results told us that with the increasing thickness of the alumina film, the Raman signals decreased. With approximately 1 nm alumina film, the remote detection limit for R6G aqueous solution reached 10-6 mol/L.

18.
Opt Express ; 24(16): 18709-17, 2016 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-27505833

RESUMO

A europium-doped (Eu-doped) silica optical fiber is fabricated using modified chemical vapor deposition (MCVD) technology. Europium fluoride (EuF3) material is introduced into the fiber core with a high temperature vaporizing technique. Its concentration is approximately 0.11 at %. The outer and core diameters of doped fiber are approximately 122 and 9 µm, respectively. Refractive index difference (RID) between core and cladding is approximately 2%. A magneto-optical effect measurement system, which is based on the Stokes polarization parameters method, is set up to analyze its magneto-optical properties. The Verdet constant of the Eu-doped optical fiber is -4.563 rad T-1m-1, which is approximately double than that of single mode fiber (SMF) at 660 nm.

19.
Dig Dis Sci ; 61(6): 1707-13, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26715500

RESUMO

BACKGROUND AND AIM: Postoperative infection is not uncommon after hepatectomy. This study assessed the effectiveness of preoperative antibiotic prophylaxis in elective hepatectomy in a randomized clinical trial setting. METHODS: A total of 120 patients who were scheduled to undergo elective hepatectomy were equally randomized to receive either intravenous cefuroxime 1.5 g (group A) or placebo (group B) within 30 min prior to skin incision. RESULTS: Overall, postoperative infection occurred in 26 (21.6 %) of the 120 patients. There was no statistically significant difference between groups A and B in the incidence of overall infection (23.3 vs. 20.0 %, P = 0.658), surgical site infection (13.3 vs. 15 %, P = 0.793), and remote site infection (13.3 vs. 11.7 %, P = 0.783). CONCLUSION: The use of preoperative antibiotic prophylaxis as a routine practice in patients undergoing elective hepatectomy is unnecessary because it does not reduce the risk of postoperative infectious complications.


Assuntos
Antibacterianos/farmacologia , Hepatectomia/efeitos adversos , Complicações Pós-Operatórias/prevenção & controle , Idoso , Antibacterianos/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
20.
Opt Express ; 23(22): 29004-13, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26561169

RESUMO

The radiation-induced photoluminescence (PL) properties of Bi/Al-codoped silica optical fibers were investigated. The Bi/Al-related materials were doped into fiber core via atomic layer deposition. The pristine fiber samples were irradiated with different doses, and its absorption and PL properties were studied. A new absorption peak appeared at approximately 580 nm, and the intensity of absorption peaks is increased with the increasing of radiation doses. When the fiber samples were excited with a 532 nm pump, the intensity of the near infrared fluorescence decreased lightly. However, when the fiber samples were excited with a 980 nm pump the intensity of the fluorescence increased significantly with the increase of radiation doses (0-2.0 kGy). The intensity of fluorescence decreased when the radiation doses were increased up to 3.0 kGy. furthermore, the fluorescence intensity of the 1410 nm band increased much more than that the 1150 nm band. In addition, the microstructural characteristics of the Bi/Al-codoped silica optical fibers were analyzed using electron spin resonance (ESR). Many radiation-induced defect centers were present, and the intensity of the ESR signals also increased with the increase of radiation doses. The photoluminescence properties and microstructural characteristics were related in the radiated Bi-related silica optical fibers. A possible underlying mechanism for the radiation-induced photoluminescence enhancement process in the Bi/Al-doped silica fiber is discussed.

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