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1.
Acta Ophthalmol ; 2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32573116

RESUMO

PURPOSE: To predict the anti-vascular endothelial growth factor (VEGF) therapeutic response of diabetic macular oedema (DME) patients from optical coherence tomography (OCT) at the initiation stage of treatment using a machine learning-based self-explainable system. METHODS: A total of 712 DME patients were included and classified into poor and good responder groups according to central macular thickness decrease after three consecutive injections. Machine learning models were constructed to make predictions based on related features extracted automatically using deep learning algorithms from OCT scans at baseline. Five-fold cross-validation was applied to optimize and evaluate the models. The model with the best performance was then compared with two ophthalmologists. Feature importance was further investigated, and a Wilcoxon rank-sum test was performed to assess the difference of a single feature between two groups. RESULTS: Of 712 patients, 294 were poor responders and 418 were good responders. The best performance for the prediction task was achieved by random forest (RF), with sensitivity, specificity and area under the receiver operating characteristic curve of 0.900, 0.851 and 0.923. Ophthalmologist 1 and ophthalmologist 2 reached sensitivity of 0.775 and 0.750, and specificity of 0.716 and 0.821, respectively. The sum of hyperreflective dots was found to be the most relevant feature for prediction. CONCLUSION: An RF classifier was constructed to predict the treatment response of anti-VEGF from OCT images of DME patients with high accuracy. The algorithm contributes to predicting treatment requirements in advance and provides an optimal individualized therapeutic regimen.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32218331

RESUMO

The sustainable utilization of water resources is a significant factor in the development of the national economy and society. Regional water resources carrying capacity (RWRCC) is an appropriate method for evaluating the balance in such utilization. In this paper, we combined time difference correlation analysis and set pair analysis firstly to identify the early warning sign index (EWSI) for RWRCC, and warning limits were determined using a logical curve. Analytic hierarchy process based on the accelerating genetic algorithm (AGA-AHP) method was used to improve the KLR model by determining weights objectively. We took advantage of the new improved model to build the aggregate warning index (AWI). Then, according to the corresponding relationship between EWSI and AWI, the early warning system for regional water resources carrying capacity (EWS-RWRCC) was established, and a case study was carried out in Anhui Province. The results showed there are eight effective EWSI obtained through the early warning analysis process of RWRCC in Anhui Province, among which the repetitive use rate of industrial water and average daily coefficient have a greater impact on AWI. Basically, the EWS-RWRCC can describe RWRCC changes in Anhui Province. From 2006 to 2014, more than half the signal lights in Anhui Province were yellow and orange, which indicated a poor state. It has been proved that the constraints of population, GDP growth and water supply capacity on the utilization of water resources in the future will be further tightened, which should be considered for future monitoring and early warning. The early warning method we used here can be widely applied into other fields; the results will enhance monitoring capacity and scientifically guide regional water resources management.

3.
J Phys Chem Lett ; : 2303-2307, 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32102543

RESUMO

HgSe colloidal quantum dot films are made by using a hybrid ligand exchange (HgSe/hybrid) in polar inks and compared with the solid-state ligand exchange using ethanedithiol (HgSe/EDT). In both systems, the conductance shows a peak at one-electron filling of the 1Se state and a dip at 2 electrons before filling the 1Pe state. The HgSe/hybrid films show a ∼100-fold increased mobility, reaching up to ∼1 cm2/Vs for 7.5 nm diameter particles. While field effect transistor and Hall measurements give similar carrier density and mobility, the temperature dependence of the mobility is consistent with hopping transport.

4.
Adv Mater ; : e1906590, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31957096

RESUMO

Three-dimensional (3D) subwavelength nanostructures have emerged and triggered tremendous excitement because of their advantages over the two-dimensional (2D) counterparts in fields of plasmonics, photonic crystals, and metamaterials. However, the fabrication and integration of 3D nanophotonic structures with colloidal quantum dots (CQDs) faces several technological obstacles, as conventional lithographic and etching techniques may affect the surface chemistry of colloidal nanomaterials. Here, the direct fabrication of functional quasi-3D nanophotonic structures into CQD films is demonstrated by one-step imprinting with well-controlled precision in both vertical and lateral directions. To showcase the potential of this technique, diffraction gratings, bilayer wire-grid polarizers, and resonant metal mesh long-pass filters are imprinted on CQD films without degrading the optical and electrical properties of CQD. Furthermore, a dual-diode CQD detector into an unprecedented mid-wave infrared two-channel polarization detector is functionalized by embedding an imprinted bilayer wire-grid polarizer within the CQDs. The results show that this approach offers a feasible pathway to combine quasi-3D nanostructures with colloidal materials-based optoelectronics and access a new level of light manipulation.

5.
Nat Mater ; 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31988516

RESUMO

Improving charge mobility in quantum dot (QD) films is important for the performance of photodetectors, solar cells and light-emitting diodes. However, these applications also require preservation of well defined QD electronic states and optical transitions. Here, we present HgTe QD films that show high mobility for charges transported through discrete QD states. A hybrid surface passivation process efficiently eliminates surface states, provides tunable air-stable n and p doping and enables hysteresis-free filling of QD states evidenced by strong conductance modulation. QD films dried at room temperature without any post-treatments exhibit mobility up to µ ~ 8 cm2 V-1 s-1 at a low carrier density of less than one electron per QD, band-like behaviour down to 77 K, and similar drift and Hall mobilities at all temperatures. This unprecedented set of electronic properties raises important questions about the delocalization and hopping mechanisms for transport in QD solids, and introduces opportunities for improving QD technologies.

6.
Nat Commun ; 10(1): 4511, 2019 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-31586067

RESUMO

Colloidal quantum wells are two-dimensional materials grown with atomically-precise thickness that dictates their electronic structure. Although intersubband absorption in epitaxial quantum wells is well-known, analogous observations in non-epitaxial two-dimensional materials are sparse. Here we show that CdSe nanoplatelet quantum wells have narrow (30-200 meV), polarized intersubband absorption features when photoexcited or under applied bias, which can be tuned by thickness across the near-infrared (NIR) spectral window (900-1600 nm) inclusive of important telecommunications wavelengths. By examination of the optical absorption and polarization-resolved measurements, the NIR absorptions are assigned to electron intersubband transitions. Under photoexcitation, the intersubband features display hot carrier and Auger recombination effects similar to excitonic absorptions. Sequenced two-color photoexcitation permits the sub-picosecond modulation of the carrier temperature in such colloidal quantum wells. This work suggests that colloidal quantum wells may be promising building blocks for NIR technologies.

7.
Talanta ; 200: 537-546, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31036220

RESUMO

Liquid chromatography-mass spectrometry based profiling of microbial metabolites has been a challenging task due to their diverse physicochemical properties and wide concentration ranges. This study is aimed to develop a systematic platform for the broad-scale profiling of microbial metabolites by integrating aqueous-lipophilic biphasic extractions and chemical derivatizations with a data-dependent automatable metabolite annotation algorithm. This complementary strategy of detection will not only largely expand the metabolite coverage, but also facilitate the drawing out of interested submetabolome using designed chemical derivatizations. Then, the data-dependent metabolite annotation algorithm is able to automatically match the raw MS/MS data with those of compounds in the self-collected databases. The performance of this platform is illustrated through the analysis of two representative bacteria (Escherichia coli and Pseudomonas aeruginosa) and intestinal contents samples from experimental colitis mice. As a result, 292 metabolites corresponding to 875 annotated features distributing over 25 chemical families were putatively annotated in a short time. Of these metabolites, 197 and 218 are respectively from the bacteria and intestinal contents, and 107 are identified in all three biological samples. This systematic platform could be used to accomplete high-coverage detection and high-quality data processing of microbial metabolites. At the same time, chemical derivatization design and the establishment of self-collected databases will facilitate self-driven untargeted analysis.


Assuntos
Colite/metabolismo , Escherichia coli/metabolismo , Pseudomonas aeruginosa/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Colite/induzido quimicamente , Colite/microbiologia , Sulfato de Dextrana , Espectrometria de Massas , Camundongos
8.
Exp Ther Med ; 17(4): 3181-3188, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30936991

RESUMO

Inflammatory bowel disease (IBD) is a risk factor in colon cancer. Endoplasmic reticulum (ER) stress is associated with IBD and cancer. In the current study an azoxymethane (AOM) and dextran sulfate sodium (DSS)-induced mouse colonic tumor model was established to analyze the expression of ER stress chaperone molecules. Female C57BL/6 mice were intraperitoneally injected with 12 mg/kg AOM. On the 7th day following AOM injection, mice were treated with 1% DSS supplemented to the drinking water for 7 days, then followed by 14 days of normal drinking water. The cycle of 7 days DSS plus 14 days normal water was repeated twice and colonic tumors were evaluated for their number and size. Mice in the control group were injected with saline and received normal drinking water for the course of the experiment. mRNA levels of cytokines, inositol-requiring enzyme (IRE)1α and 1ß, their downstream targets X-box binding protein (XBP)1u, XBP1s and mucin (MUC) 2 and interleukin (IL)-6, IL-8 and tumor necrosis factor (TNF)-α were detected by reverse transcription-quantitative polymerase chain reaction. IRE1α, IRE1ß and MUC2 protein expression was evaluated by immunohistochemistry, and IRE1α and IRE1ß levels were further assessed by western blot analysis. It was observed that tumors developed in the distal colon of mice treated with AOM/DSS. IL-6, IL-8 and TNF-α mRNA levels were significantly increased in mice of the tumor group compared with mice of the control group. There were no significant differences in IRE1α mRNA and protein expression between the two groups and XBP1s mRNA levels were increased in the tumor compared with the control group. IRE1ß and MUC2 mRNA levels were significantly decreased in the tumor compared with the control group (decreased by 42 and 30%, respectively). IRE1ß and MUC2 proteins were predominately expressed in colonic epithelial cells and expression was decreased in the tumor compared with the control group. In conclusion, the downregulation of IRE1ß and MUC2 may reduce the ability of colon tissues to resist inflammation, thus promoting the occurrence and development of colonic tumors.

9.
Psychoneuroendocrinology ; 103: 96-103, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30665044

RESUMO

Socioeconomic status (SES) disparities have profound impacts on child development and health, which are linked to negative emotions and alterations in the integrity of stress-sensitive hypothalamus-pituitary-adrenal (HPA)-axis system. However, its underlying psychophysiological mechanisms remain poorly understood. Here we investigate how family SES, in concert with parental anxiety, affects children's anxiety and their integrity of HPA-axis system in two studies involving a total of 1318 children and their parents. In Study 1 with a cohort of 1088 children and their parents, we found that low-SES children relative to high-SES ones experienced a higher level of anxiety mediated by increasing parental anxiety. In Study 2 with an independent cohort of 230 children and their parents, we found that low-SES children exhibited an increase in pre-bedtime basal cortisol but a decrease in cortisol awakening response (CAR). Structural equation modeling (SEM) further revealed that the association between low SES and children's reduced CAR was mediated by increased parental and child anxiety. Our findings suggest that low-SES children are more vulnerable to anxiety and altered HPA-axis integrity, most likely mediated through increased parental anxiety.


Assuntos
Ansiedade/fisiopatologia , Classe Social , Estresse Psicológico/psicologia , Adolescente , Ansiedade/etiologia , Ansiedade/metabolismo , Transtornos de Ansiedade/metabolismo , Transtornos de Ansiedade/fisiopatologia , Criança , Ritmo Circadiano , Estudos de Coortes , Família/psicologia , Feminino , Humanos , Hidrocortisona/análise , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Pais/psicologia , Sistema Hipófise-Suprarrenal/fisiologia , Saliva/química
10.
J Cell Biochem ; 120(6): 9230-9242, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30525222

RESUMO

AIM: This study investigated the impact of 5-hydroxytryptamine (5-HT) on the expression of NOXs in dextran sulfate sodium (DSS)-induced colitis in mice. METHODS: C57BL/6J (B6) mice at 6 to 8 weeks of age were treated with 5-HT, DSS, or DSS + 5-HT. After 6-day treatment, the severity of colitis, infiltration of leukocytes, and messenger RNA (mRNA) and/or protein levels of Nox1, Nox2, Nox4, and Duox2 were analyzed in the colon by real-time quantitative polymerase chain reaction (qPCR), immunohistochemistry (IHC), and Western blot analysis. The direct effect of 5-HT on NOX gene and protein expression in HT-29 colon cancer cells and in U-937 macrophage cells were determined by qPCR and Western blot analysis. RESULTS: Mice treated with 5-HT alone did not develop colitis, while those treated with 1.0% DSS or DSS + 5-HT had mild and severe colitis, respectively. All treated mice had more myeloperoxidase-positive cells in the colon compared with untreated control mice. Mice treated with 5-HT or DSS alone had increased Nox2 and Nox4 mRNA and protein levels in the colon determined by qPCR, IHC, and Western blot analysis. These two Nox expressions were even higher in mice treated with DSS + 5-HT, while the expression levels of epithelium-localized Nox1 and Duox2 tended to decrease. Additionally, mice treated with 5-HT alone had elevated Nox1 and Duox2 expression as shown by qPCR and IHC. However, these gene expressions were diminished in DSS + 5-HT-treated mice likely due to erosion of epithelium. Furthermore, 5-HT induced NOX1 and DUOX2 gene and protein expression in HT-29 colon cancer epithelial cells, whereas induced NOX2 and NOX4 gene and protein expression in U-937 cells. CONCLUSION: As 5-HT induced NOX1 and DUOX2 gene and protein expression in colon epithelial and HT-29 cells, NOX2 and NOX4 in the infiltrating leukocyte in mouse colon and in U-937 cells, the exacerbate colitis induced by combined 5-HT and DSS treatment might be relevant to increased NOX expression in mice colons.

11.
Front Immunol ; 9: 2647, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30519240

RESUMO

Amyotrophic Lateral Sclerosis (ALS) is a group of neurodegenerative disorders that featured with the death of motor neurons, which leads to loss of voluntary control on muscles. The etiologies vary among different subtypes of ALS, and no effective management or medication could be provided to the patients, with the underlying mechanisms incompletely understood yet. Mutations in human Optn (Optineurin), particularly E478G, have been found in many ALS patients. In this work, we report that NF-κB activity was increased in Optn knockout (Optn -/-) MEF (mouse embryonic fibroblast) cells expressing OPTN of different ALS-associated mutants especially E478G. Inflammation was significantly activated in mice infected with lenti-virus that allowed overexpression of OPTN E478G mutation in the motor cortex, with marked increase in the secretion of pro-inflammatory cytokines as well as neuronal cell death. Our work with both cell and animal models strongly suggested that anti-inflammation treatment could represent a powerful strategy to intervene into disease progression in ALS patients who possess the distinctive mutations in OPTN gene.


Assuntos
Esclerose Amiotrófica Lateral/imunologia , Mutação de Sentido Incorreto , Neurônios/imunologia , Fator de Transcrição TFIIIA/imunologia , Substituição de Aminoácidos , Esclerose Amiotrófica Lateral/genética , Esclerose Amiotrófica Lateral/patologia , Animais , Morte Celular/genética , Morte Celular/imunologia , Embrião de Mamíferos , Proteínas do Olho/genética , Proteínas do Olho/imunologia , Fibroblastos/imunologia , Fibroblastos/patologia , Humanos , Camundongos , Neurônios/patologia , Fator de Transcrição TFIIIA/genética
12.
ACS Nano ; 12(9): 9397-9404, 2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-30125488

RESUMO

HgTe colloidal quantum dots (QDs) are of interest because quantum confinement of semimetallic bulk HgTe allows one to synthetically control the bandgap throughout the infrared. Here, we synthesize highly monodisperse HgTe QDs and tune their doping both chemically and electrochemically. The monodispersity of the QDs was evaluated using small-angle X-ray scattering (SAXS) and suggests a diameter distribution of ∼10% across multiple batches of different sizes. Electron-doped HgTe QDs display an intraband absorbance and bleaching of the first two excitonic features. We see splitting of the intraband peaks corresponding to electronic transitions from the occupied 1Se state to a series of nondegenerate 1Pe states. Spectroelectrochemical studies reveal that the degree of splitting and relative intensity of the intraband features remain constant across doping levels up to two electrons per QD. Theoretical modeling suggests that the splitting of the 1Pe level arises from spin-orbit coupling and reduced QD symmetry. The fine structure of the intraband transitions is observed in the ensemble studies due to the size uniformity of the as-synthesized QDs and strong spin-orbit coupling inherent to HgTe.

13.
Arthritis Res Ther ; 20(1): 20, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29415757

RESUMO

BACKGROUND: In addition to the kidney, the intestine is one of the most important organs involved in uric acid excretion. However, the mechanism of urate excretion in the intestine remains unclear. Therefore, the relationship between soluble uric acid and the gut excretion in human intestinal cells was explored. The relevant signaling molecules were then also examined. METHODS: HT-29 and Caco-2 cell lines were stimulated with soluble uric acid. Western blotting and qRT-PCR were used to measure protein and mRNA levels. Subcellular fractionation methods and immunofluorescence were used to quantify the proteins in different subcellular compartments. Flow cytometry experiments examined the function of ATP-binding cassette transporter, subfamily G, member 2 (ABCG2). Small interfering RNA transfection was used to assess the interaction between ABCG2 and PDZ domain-containing 1 (PDZK1). RESULTS: Soluble uric acid increased the expression of PDZK1 and ABCG2. The stimulation of soluble uric acid also facilitated the translocation of ABCG2 from the intracellular compartment to the plasma membrane and increased its transport activity. Moreover, the upregulation of PDZK1 and ABCG2 by soluble uric acid was partially decreased by either TLR4-NLRP3 inflammasome inhibitors or PI3K/Akt signaling inhibitors. Furthermore, PDZK1 knockdown significantly inhibited the expression and transport activity of ABCG2 regardless of the activation by soluble uric acid, demonstrating a pivotal role for PDZK1 in the regulation of ABCG2. CONCLUSIONS: These findings suggest that urate upregulates the expression of PDZK1 and ABCG2 for excretion in intestinal cells via activating the TLR4-NLRP3 inflammasome and PI3K/Akt signaling pathway.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Transporte/metabolismo , Colo/efeitos dos fármacos , Inflamassomos/efeitos dos fármacos , Proteínas de Neoplasias/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ácido Úrico/farmacologia , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Células CACO-2 , Proteínas de Transporte/genética , Colo/metabolismo , Colo/patologia , Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , Inflamassomos/metabolismo , Proteínas de Membrana , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas de Neoplasias/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Solubilidade , Receptor 4 Toll-Like/metabolismo , Ácido Úrico/química
14.
J Pharm Biomed Anal ; 145: 666-674, 2017 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-28800528

RESUMO

Traditional Chinese medicine (TCM) materials with closely related species are frequently fungible in clinical use. Therefore, holistic comparison of the composition in bioactive compounds is essential to evaluate whether they are equivalent in efficacy. Taking three officinal species of Callicarpa as a case, we proposed and validated a standardized strategy for the discrimination of closely related TCM materials, which focused on the extraction, profiling and multivariate statistical analysis of their biochemome. Firstly, serial liquid-liquid extractions were utilized to prepare different batches of Callicarpa biochemome, and the preparation yields were utilized for the normalization of sampling quantity prior to UHPLC-IT-MS analysis. Secondly, 34 compounds, including 19 phenylethanoid glycosides, 10 flavonoids and 5 terpenoids, were identified based on an untargeted UHPLC-IT-MS method. Thirdly, method validation of linearity, precision and stability showed that the UHPLC-IT-MS system was qualified (R2>0.995, RSD<15%) for subsequent biochemome profiling. After PCA and PLS-DA analysis, 30 marker compounds were screened and demonstrated to be of good predictability using genetic algorithm optimized support vector machines. Finally, a heatmap visualization was employed for clarifying the distribution of marker compounds, which could be helpful to determine whether the three Callicarpa species are, in fact, equivalent substitutes. This study provides a standardized biochemome profiling strategy for systemic comparison analysis of closely related TCM materials, which shows promising perspectives in tracking the supply chain of pharmaceutical suppliers.


Assuntos
Callicarpa , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas , Extração Líquido-Líquido , Medicina Tradicional Chinesa
15.
Anal Chim Acta ; 977: 28-35, 2017 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-28577595

RESUMO

In this study, a new strategy combining mass spectrometric (MS) techniques with partial least squares regression (PLSR) was proposed to identify and quantify closely related adulterant herbal materials. This strategy involved preparation of adulterated samples, data acquisition and establishment of PLSR model. The approach was accurate, sensitive, durable and universal, and validation of the model was done by detecting the presence of Fritillaria Ussuriensis Bulbus in the adulteration of the bulbs of Fritillaria unibracteata. Herein, three different MS techniques, namely wooden-tip electrospray ionization mass spectrometry (wooden-tip ESI/MS), ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS) and UPLC-triple quadrupole tandem mass spectrometry (UPLC-TQ/MS), were applied to obtain MS profiles for establishing PLSR models. All three models afforded good linearity and good accuracy of prediction, with correlation coefficient of prediction (rp2) of 0.9072, 0.9922 and 0.9904, respectively, and root mean square error of prediction (RMSEP) of 0.1004, 0.0290 and 0.0323, respectively. Thus, this strategy is very promising in tracking the supply chain of herb-based pharmaceutical industry, especially for identifying adulteration of medicinal materials from their closely related herbal species.


Assuntos
Contaminação de Medicamentos , Fritillaria/química , Preparações de Plantas/normas , Cromatografia Líquida de Alta Pressão , Análise dos Mínimos Quadrados , Preparações de Plantas/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
16.
J Phys Chem Lett ; 8(10): 2224-2228, 2017 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-28467091

RESUMO

Nonaggregating HgTe colloidal quantum dots are synthesized without thiols as stabilizing ligands. The dots are spherical with a size tunability from 4.8 to 11.5 nm. When the results from optical and electrochemical measurement are combined, air-stable n-doping is observed in large sizes of HgTe quantum dots, which is attributed to the Hg-rich surface.

17.
ACS Nano ; 11(4): 4165-4173, 2017 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-28314094

RESUMO

The absolute positions of the energy levels of colloidal quantum dots of Hg(S, Se, Te), which are of interest as mid-infrared materials, are determined by electrochemistry. The bulk valence bands are at -5.85, -5.50, and -4.77 eV (±0.05 eV) for zinc-blend HgS, HgSe, HgTe, respectively, in the same order as the anions p-orbital energies. The conduction bands are conversely at -5.20, -5.50, and -4.77 eV. The stable ambient n-doping of Hg(S, Se) quantum dots compared to HgTe arises because the conduction band is sufficiently lower than the measured environment Fermi level of ∼ -4.7 eV to allow for n-doping for HgS and HgSe quantum dots even with significant electron confinement. The position of the Fermi level and the quantum dots states are reported for a specific surface treatment with ethanedithiol and electrolyte environment. The positions are however sensitive to different surface treatments, providing an avenue to control doping. Electrochemical gating is further used to determine the carrier mobility in the films of the three different systems as a function of CQD size. HgSe and HgS show increasing mobility with increasing particle sizes while HgTe shows a nonmonotonous behavior, which is attributed to some degree of aggregation of HgTe QDs.

18.
Kidney Blood Press Res ; 41(6): 911-918, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27889773

RESUMO

BACKGROUND/AIMS: The aminolycoside Gentamicin is a widely used antibiotic, applied in equine medicine. Despite its clinical use, concerns remain regarding the potential toxic side-effects, such as nephrotoxicity. Early detection of renal damage is critical in preclinical drug development. This study was aimed to determine whether kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) may be early indicators in the assessment of Gentamycin-induced nephrotoxicity. METHODS: In our study, a model of Gentamicin-induced nephrotoxicity in male Sprague Dawley rats treated for up to 7 days at 50 or 100mg/kg/day was used to monitor the expressions of novel biomarkers of renal toxicity during the progression of acute kidney injury (AKI). Additionally, biomarkers were assessed in human kidney proximal epithelial cells (HK-2) treated with Gentamicin for 2, 6, 12, 24, 36 or 48h in vitro. RESULTS: Repeated administration of Gentamicin to rats for 1, 3, or 7 days resulted in a dose- and time-dependent increase in the expression of KIM-1 and NGAL. The expressions of the two biomarkers changed prior to renal tubule damage and increases in serum creatinine (SCr) and blood urea nitrogen (BUN) levels, suggesting their usefulness for predicting Gentamicin-induced acute kidney injury (AKI) in vivo. CONCLUSIONS: In contrast, no significant increase in the expression of the biomarker genes and proteins were evident in HK-2 cells after treated by Gentamycin for up to 48h, suggesting that they may not be suitable endpoints for sensitive detection of nephrotoxic effects in vitro.


Assuntos
Lesão Renal Aguda/sangue , Moléculas de Adesão Celular/sangue , Lipocalinas/sangue , Proteínas Proto-Oncogênicas/sangue , Lesão Renal Aguda/induzido quimicamente , Lesão Renal Aguda/diagnóstico , Proteínas da Fase Aguda , Animais , Biomarcadores/sangue , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Gentamicinas/toxicidade , Humanos , Masculino , Ratos , Ratos Sprague-Dawley
19.
Mediators Inflamm ; 2016: 5359768, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27478308

RESUMO

Background. 5-HT enhances dextran sulfate sodium- (DSS-) induced colitis and is involved in inflammatory bowel disease (IBD). Matrix metalloproteinases (MMPs) play roles in the process of intestinal inflammation. Aims. To examine whether 5-HT induces MMPs expression in mouse colon to enhance DSS-induced colitis. Materials and Methods. C57BL/6J (B6) mice were treated with either low-dose (1.0 mg/kg) or high-dose (2.0 mg/kg) 5-HT by enema, low-dose (1.0%) or high-dose (2.5%) DSS, or combined low-dose (1.0%) DSS and (1.0 mg/kg) 5-HT. Mouse colitis was analyzed. MMPs and tissue inhibitors of MMPs (TIMPs) mRNA were measured by real-time quantitative RT-PCR in mouse colon and in human Caco-2 cells and neutrophils. MMP-3 and MMP-9 protein levels were quantified from immunohistochemistry (IHC) images of mouse colons. Results. 5-HT exacerbated DSS-induced colitis, low-dose 5-HT induces both MMP-3 and MMP-9, and high-dose 5-HT only increased MMP-3 mRNA expression in mouse colon. Mouse colon MMP-3 and MMP-9 protein levels were also elevated by 5-HT treatment. The MMP-2, TIMP-1, and TIMP-2 mRNA levels were increased in the inflamed colon. 5-HT induced MMP-3 and MMP-9 mRNA expression in Caco-2 and human neutrophils, respectively, in vitro. Conclusion. 5-HT induced MMP-3 and MMP-9 expression in mouse colon; these elevated MMPs may contribute to DSS-induced colitis.


Assuntos
Colite/induzido quimicamente , Colite/metabolismo , Colo/metabolismo , Metaloproteinase 3 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Serotonina/farmacologia , Animais , Células CACO-2 , Colo/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase em Tempo Real
20.
Mol Cell Biochem ; 397(1-2): 53-60, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25087119

RESUMO

Gentamicin is a member of aminoglycosides, which has represented highly effective antimicrobial agents especially in Gram-negative infections despite their toxic effects in the kidney. Rapid diagnosis is vital to preserve renal function and to slow down renal injury. Owing to the poor sensitivity and specificity of serum creatinine (SCr) and blood urea nitrogen (BUN), new biomarkers for earlier and more accurate detection are needed. The aim of our study was to determine whether kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) may be useful biomarkers in the assessment of gentamicin-induced nephrotoxicity in rats. In this study, the two biomarkers of renal toxicity were assessed via ELISA, quantitative real-time PCR, and immunohistochemistry in rats treated with gentamicin for up to 7 days. Repeated administration of gentamicin to male SD rats for 1, 3, or 7 days resulted in a dose- and time-dependent increase in the expression of KIM-1 and NGAL. Changes in gene and protein expressions were found to correlate with the progressive histopathological alterations and preceded effects on traditional clinical parameters indicative of impaired kidney function. Both of the biomarkers are supported to be used as sensitive indicators of acute kidney injury caused by gentamicin.


Assuntos
Lesão Renal Aguda/sangue , Antibacterianos/efeitos adversos , Moléculas de Adesão Celular/sangue , Regulação da Expressão Gênica/efeitos dos fármacos , Gentamicinas/efeitos adversos , Lipocalinas/sangue , Proteínas Proto-Oncogênicas/sangue , Lesão Renal Aguda/induzido quimicamente , Lesão Renal Aguda/patologia , Proteínas da Fase Aguda , Animais , Antibacterianos/farmacologia , Biomarcadores/sangue , Gentamicinas/farmacologia , Masculino , Ratos , Ratos Sprague-Dawley
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