Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Opt Express ; 31(22): 36209-36218, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-38017775

RESUMO

Non-line-of-sight (NLOS) technology has been rapidly developed in recent years, allowing us to visualize or localize hidden objects by analyzing the returned photons, which is expected to be applied to autonomous driving, field rescue, etc. Due to the laser attenuation and multiple reflections, it is inevitable for future applications to separate the returned extremely weak signal from noise. However, current methods find signals by direct accumulation, causing noise to be accumulated simultaneously and inability of extracting weak targets. Herein, we explore two denoising methods without accumulation to detect the weak target echoes, relying on the temporal correlation feature. In one aspect, we propose a dual-detector method based on software operations to improve the detection ability for weak signals. In the other aspect, we introduce the pipeline method for NLOS target tracking in sequential histograms. Ultimately, we experimentally demonstrated these two methods and extracted the motion trajectory of the hidden object. The results may be useful for practical applications in the future.

2.
Sensors (Basel) ; 23(11)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37299857

RESUMO

Tunable Diode Laser Absorption Spectroscopy (TDLAS) has been widely applied in in situ and real-time monitoring of trace gas concentrations. In this paper, an advanced TDLAS-based optical gas sensing system with laser linewidth analysis and filtering/fitting algorithms is proposed and experimentally demonstrated. The linewidth of the laser pulse spectrum is innovatively considered and analyzed in the harmonic detection of the TDLAS model. The adaptive Variational Mode Decomposition-Savitzky Golay (VMD-SG) filtering algorithm is developed to process the raw data and could significantly eliminate the background noise variance by about 31% and signal jitters by about 12.5%. Furthermore, the Radial Basis Function (RBF) neural network is also incorporated and applied to improve the fitting accuracy of the gas sensor. Compared with traditional linear fitting or least squares method (LSM), the RBF neural network brings along the enhanced fitting accuracy within a large dynamic range, achieving an absolute error of below 50 ppmv (about 0.6%) for the maximum 8000 ppmv methane. The proposed technique in this paper is universal and compatible with TDLAS-based gas sensors without hardware modification, allowing direct improvement and optimization for current optical gas sensors.


Assuntos
Lasers Semicondutores , Dispositivos Ópticos , Algoritmos , Análise Espectral , Redes Neurais de Computação
3.
J Neuroinflammation ; 19(1): 145, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35701825

RESUMO

BACKGROUND: Exposure to sunlight may decrease the risk of developing Alzheimer's disease (AD), and visible and near infrared light have been proposed as a possible therapeutic strategy for AD. Here, we investigated the effects of the visible, near infrared and far infrared (FIR) light on the cognitive ability of AD mice, and found that FIR light also showed potential in the improvement of cognitive dysfunction in AD. However, the related mechanism remains to be elucidated. METHODS: Morris water maze was used to evaluate the cognitive ability of APPswe/PSEN1dE9 double-transgenic AD mice after light treatment. Western blot was carried out to detect the expression of protein involved in synaptic function and amyloid-ß (Aß) production. The protein amount of interleukin (IL)-1ß, IL-6, Aß1-40 and Aß1-42 were determined using enzyme-linked immunosorbent assay. The mRNA level of receptors was performed using real-time quantitative polymerase chain reaction. Immunostaining was performed to characterize the Aß burden and microglial Aß phagocytosis in the brain of AD mice. The Aß phagocytosis of primary cultured microglia and BV2 were assessed by flow cytometry. The energy metabolism changes were evaluated using related assay kits, including adenosine triphosphate (ATP), lactate content, mitochondrial respiratory chain complex enzymatic activity and oxidized/reduced nicotinamide adenine dinucleotide assay kits. RESULTS: Our results showed that FIR light reduced Aß burden, a hallmark of AD neuropathology, alleviated neuroinflammation, restored the expression of the presynaptic protein synaptophysin, and ameliorated learning and memory impairment in the AD mice. FIR light enhanced mitochondrial oxidative phosphorylation pathway to increase ATP production. This increased intracellular ATP promoted the extracellular ATP release from microglia stimulated by Aß, leading to the enhanced Aß phagocytosis through phosphoinositide 3-kinase/mammalian target of rapamycin pathways for Aß clearance. CONCLUSIONS: Our findings have uncovered a previously unappreciated function of FIR light in inducing microglial phagocytosis to clean Aß, which may be the mechanisms for FIR light to improve cognitive dysfunction in AD mice. These results suggest that FIR light treatment is a potential therapeutic strategy for AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Trifosfato de Adenosina/farmacologia , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Cognição , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/terapia , Modelos Animais de Doenças , Mamíferos/metabolismo , Camundongos , Camundongos Transgênicos , Microglia/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo
4.
Genomics ; 112(3): 2510-2515, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32045670

RESUMO

To investigate the association between SNPs in human IGF2/H19 gene locus and epithelial ovarian cancer (EOC) risk, we performed a case-control study in 422 individuals (219 EOC patients and 203 cancer-free controls). Four SNPs (rs2525885, rs2839698, rs3741206, rs3741219) were found to be related with EOC risk. Specifically, the minor allele C of rs2525885 and allele A of rs2839698 was associated with elevated EOC genetic susceptibility under both dominant and recessive models (TC + CC vs TT: adjusted OR: 1.61, P = .031; CC vs TT + TC: adjusted OR: 4.87, P = .014; GA + AA vs GG: adjusted OR: 1.63, P = .023; AA vs GG + GA: adjusted OR: 2.43, P = .007). For rs3741206, the genotype TC + CC was associated with a significant decrease in EOC risk with the TT genotype as reference in a dominant genetic model (adjusted OR: 0.44, P = .003), while for rs3741219, genotype AA was associated with a 59% decrease in EOC risk only in the recessive model (adjusted OR: 0.41, P = .038). In the stratified analysis, an increased risk associated with the variant genotypes was observed in only subjects aged >47 years for rs2525885 (adjusted OR = 2.04, P = .024), rs2839698 (adjusted OR = 2.50, P = .047) and rs3741206 (adjusted OR = 0.37, P = .009), respectively. What's more, the TC + CC genotype of rs2525885 was significantly associated with advanced FIGO stage (III vs II, adjusted OR = 2.73, P = .040).


Assuntos
Carcinoma Epitelial do Ovário/genética , Fator de Crescimento Insulin-Like II/genética , Neoplasias Ovarianas/genética , Polimorfismo de Nucleotídeo Único , RNA Longo não Codificante/genética , Adulto , Carcinoma Epitelial do Ovário/patologia , Estudos de Casos e Controles , China , Feminino , Frequência do Gene , Loci Gênicos , Predisposição Genética para Doença , Genótipo , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Fatores de Risco
5.
Int J Clin Pharmacol Ther ; 55(10): 774-780, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28737129

RESUMO

The copper transporters CTR1, CTR2, ATP7A, and ATP7B regulate intracellular concentration of platinum by mediating its uptake and efflux in cells. We sought to explore the effect of genetic polymorphisms in CTR1, CTR2, ATP7A, and ATP7B on platinum resistance in patients suffering from epithelial ovarian cancer (EOC). A total of 152 Chinese EOC patients were enrolled in this study, all of whom underwent adjuvant chemotherapy using platinum and taxane after maximal debulking surgery. In total, 11 single-nucleotide polymorphisms (SNPs) in CTR1, CTR2, ATP7A, and ATP7B were genotyped in these patients. The CTR1 rs10981694 polymorphism was observed to be associated with carboplatin resistance, while patients with the rs10981694 G allele showed a significantly higher rate of carboplatin resistance (OR = 4.00, 95% CI 1.309 - 12.23, p < 0.01). In addition, we found that ATP7A rs2227291 was associated with cisplatin resistance and that carriers of the C allele were more sensitive to cisplatin (OR = 0.40, 95% CI: 0.17 - 0.94, p = 0.03). Our findings suggest that the CTR1 and ATP7A genetic polymorphisms could affect platinum resistance. The CTR1 and ATP7A genes might be considered a predictive marker for carboplatin and cisplatin resistance, respectively.
.


Assuntos
Proteínas de Transporte de Cátions/genética , ATPases Transportadoras de Cobre/genética , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Epiteliais e Glandulares/genética , Compostos Organoplatínicos/uso terapêutico , Neoplasias Ovarianas/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Idoso , Antineoplásicos/uso terapêutico , Carcinoma Epitelial do Ovário , Transportador de Cobre 1 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Proteínas SLC31
6.
J Pharmacol Exp Ther ; 354(3): 310-5, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26081159

RESUMO

Rosuvastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor used to lower blood low-density lipoprotein cholesterol, is a substrate of the membrane ABCG2 exporter. ABCG2 variants have been shown to alter rosuvastatin disposition. The objective of this study is to determine the impact of ABCG2 34/421 compound haplotypes on rosuvastatin pharmacokinetics in healthy Chinese volunteer subjects. Eight hundred healthy Chinese males were genotyped by polymerase chain reaction-pyrosequencing for ABCG2 34G>A, ABCG2 421C>A, SLCO1B1 521T>C, and CYP2C9*3 variants. Sixty-two male subjects with wild-type SLCO1B1 c.521TT and CYP2C9*3 were recruited for this pharmacokinetic study of rosuvastatin. A single oral dose of 10 mg rosuvastatin was administrated to each subject, and blood samples were collected before and at various time points after drug administration. Plasma concentration of rosuvastatin was determined by high-performance liquid chromatography-tandem mass spectrometry, and pharmacokinetic analysis was carried out using the WinNonlin program. In Chinese males, high allele frequency of ABCG2 c.34G>A (0.275) and c.421C>A (0.282) was observed, resulting in a considerable portion (23.3%) of subjects being ABCG2 34/421 compound heterozygotes. Compared with subjects with ABCG2 wild-type (c.34GG/421CC), plasma rosuvastatin Cmax and area under the curve, AUC0-∞, were significantly higher, while the apparent oral clearance, CL/F, was significantly lower in subjects with c.34AA, c.421AA, and c.34GA/421CA genotypes. Both t1/2 and Tmax were similar among subjects with different genotypes. A high frequency of ABCG2 c.34G>A and c.421C>A variants was present in Chinese males, and the disposition of rosuvastatin was significantly affected by both variants. These data suggest that it is advisable to genotype these variants when prescribing rosuvastatin to Chinese subjects, leading to a precise dose for each individual.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Povo Asiático/genética , Fluorbenzenos/farmacocinética , Variação Genética/genética , Proteínas de Neoplasias/genética , Pirimidinas/farmacocinética , Sulfonamidas/farmacocinética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Adolescente , Adulto , Citocromo P-450 CYP2C9/genética , Frequência do Gene/efeitos dos fármacos , Frequência do Gene/genética , Variação Genética/efeitos dos fármacos , Genótipo , Heterozigoto , Homozigoto , Humanos , Transportador 1 de Ânion Orgânico Específico do Fígado , Masculino , Transportadores de Ânions Orgânicos/genética , Rosuvastatina Cálcica , Adulto Jovem
7.
Photoacoustics ; 32: 100526, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37456141

RESUMO

In this paper, we propose and experimentally demonstrate a symmetric multi-resonant cavity photoacoustic cell (MR-PAC) with dual microphones detection, based on multi-resonator photoacoustic spectroscopy (MR-PAS). The designed photoacoustic cell contains three interconnected acoustic resonators to facilitate simultaneous control of three lasers for multi-gas sensing. Two microphones are symmetrically located at both sides of photoacoustic cell to implement two-point detection. The length of acoustic resonator is about 50 mm to minimize the photoacoustic cell, and the resonant frequency is around 3000 Hz. Feasibility and performance of the MR-PAC was demonstrated by simultaneous detection of C2H2, NO and CF4 using a near infrared diode laser and two mid infrared quantum cascade lasers. The minimum detection limits (MDLs) of C2H2, NO and CF4 are 480 ppb, 260 ppb and 0.57 ppb respectively with a 1 s integration time at normal atmospheric pressure. This minimized MR-PAS system is promising for the portable multi-gas sensing.

8.
Sci Data ; 10(1): 515, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37542067

RESUMO

As a network of researchers we release an open-access database (EUSEDcollab) of water discharge and suspended sediment yield time series records collected in small to medium sized catchments in Europe. EUSEDcollab is compiled to overcome the scarcity of open-access data at relevant spatial scales for studies on runoff, soil loss by water erosion and sediment delivery. Multi-source measurement data from numerous researchers and institutions were harmonised into a common time series and metadata structure. Data reuse is facilitated through accompanying metadata descriptors providing background technical information for each monitoring station setup. Across ten European countries, EUSEDcollab covers over 1600 catchment years of data from 245 catchments at event (11 catchments), daily (22 catchments) and monthly (212 catchments) temporal resolution, and is unique in its focus on small to medium catchment drainage areas (median = 43 km2, min = 0.04 km2, max = 817 km2) with applicability for soil erosion research. We release this database with the aim of uniting people, knowledge and data through the European Union Soil Observatory (EUSO).

9.
Photoacoustics ; 27: 100382, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36068799

RESUMO

A small-volume highly-sensitive photoacoustic spectroscopy (PAS) methane detection system based on differential silicon cantilever optical microphones (SCOMs) is proposed and experimentally demonstrated. The system contains a compact non-resonant photoacoustic cell with a small volume of 1.2 mL and symmetrically-located dual SCOMs, as well as a distributed feedback laser at 1650.96 nm. The two identical SCOMs utilize the Fabry-Perot interferometric fiber-optic structure, with the differential Q-point demodulation algorithm to suppress the external vibration noise. Experimental results show that the SCOM has a high displacement sensitivity about 7.1 µm/Pa at 150 Hz and within 2.5 dB fluctuation between 5 Hz and 250 Hz. In the PAS gas sensing experiment, the normalized noise equivalent absorption coefficient of the PAS system is estimated to be 1.2 × 10-9 cm-1·W·Hz-1/2 and the minimum detection limit for methane is about 111.2 ppb with 1 s integration time. External disturbance is also applied to the dual SCOM system and results show excellent stability and noise resistance. The proposed PAS system exhibits superiorities of low gas consumption, high sensitivity and immunity to vibration and electromagnetic interference, which has an enormous potential in medicine, industry and environment.

10.
Waste Manag ; 126: 832-842, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33895565

RESUMO

A systematic investigation was conducted onthe co-pyrolysisof Fe3O4and PVC mixtures in temperatures as high as 1373 K upon the development of PVC recycling technology that mitigates chlorine emission. Central to our investigation, PVC decomposition plays the leading role in the co-pyrolysis of Fe3O4and PVC mixtures following a two-stage pattern bifurcated at a temperature of 673 K. In Stage 1, at temperatures 673 K and lower, Fe3O4is chlorinated by chlorine from PVC, resulting in FeCl2. The composition of the final solid residue of Stage 1,conjugated polyene, FeCl2and Fe3O4/Fe2O3, depends on the initial Fe3O4content in the mixture. When the temperature is increased to be higher than 673 K, decomposition of conjugated polyene occurs simultaneously with the stepwise reduction of Fe3O4/Fe2O3: Fe2O3 â†’ Fe3O4 â†’ FeO â†’ Fe. However, in mixtures containing Fe3O4that is less than 39.6% of the mass, Fe3O4can coexist with Fe; therefore, the FeO formation step is skipped. Most FeCl2escapes from the reaction system as vapor, showing the necessity of removing FeCl2at the end of Stage 1 to avoid harmful substance emission. The presence of Fe3O4can significantly suppress gaseous emissions, especially HCl originating from PVC decomposition. There was only 0.6% HCl by mass (2.4% PVC base by mass) released when co-pyrolyzing the PVC + 75% Fe3O4mixture due to the complete consumption of PVC and its decomposition products by Fe3O4. After separating FeCl2,which is a valuable chemical feedstock, by water-leaching the solid residue obtained at 673 K, the filtered residue,which is a mixture of Fe3O4/Fe2O3and polyene, was confirmedto be suitable for iron-making. The results clearly show the possibility of developing a PVC recycling technology with mitigated chlorine emissions by manipulating the amount of Fe3O4added.


Assuntos
Cloro , Cloreto de Vinil , Cloreto de Polivinila , Pirólise , Reciclagem
11.
Pharmacogenomics ; 20(3): 179-188, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30672383

RESUMO

AIM: The present study aimed to assess the association between IGF2/H19 genetic variants and susceptibility to platinum-based chemotherapy in epithelial ovarian cancer (EOC). METHODS: A total of 43 platinum-resistant (PR) and 138 platinum-sensitive (PS) EOC patients were recruited in our study. 21 polymorphisms in IGF2/H19 locus were genotyped by Sequenom MassARRAY assay. RESULTS: The frequencies of GG genotype in both rs3842761(C/G) and rs4244809(A/G) were significantly lower in PR group compared with those in PS group (9.76 vs 23.36%, p = 0.049; 9.76 vs 26.09%, p = 0.045; respectively). Compared with the AA genotype, rs4244809 GG genotype was associated with significantly reduced risk of platinum resistance (adjusted OR: 0.30; 95% CI: 0.10-0.91; p = 0.033). Further stratified analyses revealed that the SNPs of rs3842761 and rs4244809 were greatly related to PR risk in FIGO stage III-IV (rs3842761GG/CC+CG: adjusted OR: 0.15; 95% CI: 0.02-1.21; rs4244809 GG/AA+AG: adjusted OR: 0.24; 95% CI: 0.07-0.84; respectively) and serous adenocarcinoma subgroups (rs3842761 GG/CC+CG: adjusted OR: 0.21; 95% CI: 0.05-0.94; rs4244809 GG/AA+AG: adjusted OR: 0.19; 95% CI: 0.04-0.5; respectively), while rs7924316 polymorphism was associated with reduced risk of PR in serous adenocarcinoma subgroup as analyzed by a recessive model (rs7924316 GG/TT+TG: adjusted OR: 0.22; 95% CI: 0.05-0.98). In addition, both TCT haplotypes of rs3741206/rs3842761/rs7924316 and TC haplotype of rs3741206/rs3842761 were associated with elevated risk of PR (for the TCT haplotype of rs3741206/rs3842761/rs7924316: p = 0.049; OR: 1.69; 95% CI: 1.00-2.87; for the TC haplotype of rs3741206/rs3842761: p = 0.044; OR: 1.71; 95% CI: 1.01-2.88). CONCLUSION: These results suggest that polymorphisms in IGF2/H19 gene locus are associated with PR risk in EOC.


Assuntos
Carcinoma Epitelial do Ovário/tratamento farmacológico , Cistadenocarcinoma Seroso/tratamento farmacológico , Estudos de Associação Genética , Fator de Crescimento Insulin-Like II/genética , RNA Longo não Codificante/genética , Adulto , Idoso , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/patologia , China/epidemiologia , Cistadenocarcinoma Seroso/genética , Cistadenocarcinoma Seroso/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Genótipo , Haplótipos/genética , Humanos , Pessoa de Meia-Idade , Platina/administração & dosagem , Platina/efeitos adversos , Polimorfismo de Nucleotídeo Único/genética
12.
Oncol Rep ; 33(6): 3045-52, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25846769

RESUMO

Estrogen plays a critical role in breast cancer development and progression. However, the mechanism involved in the promotion of breast cancer development and progression by estrogen remains unclear although it has been intensively studied. In the present study, we investigated the estrogen inducibility and functional significance of H19 lncRNA in breast cancer cells and tumor tissues. The screening of 83 disease-related long non-coding RNAs (lncRNAs) revealed that H19 lncRNA was much higher in estrogen receptor (ER)-positive MCF-7 breast cancer cells than in ER-negative MDA-MB-231 cells. 17ß-estradiol produced a dose- and time-dependent induction of H19 expression in MCF-7 cells, which was mediated via ERα as evident by the blockade of this 17ß-estradiol effect with ICI 182780, a specific ER antagonist and knockdown of ERα using specific RNAi. Moreover, knockdown of H19 lncRNA decreased cell survival and blocked estrogen-induced cell growth while overexpression of H19 lncRNA stimulated cell proliferation. Quantitation of H19 lncRNA in human breast cancer tissues showed that the level of H19 lncRNA was >10-fold higher in ER-positive than in ER-negative tumor tissues. These results suggest that H19 is an estrogen-inducible gene and plays a key role in cell survival and in estrogen-induced cell proliferation in MCF-7 cells, indicating that H19 lncRNA may serve as a biomarker for breast cancer diagnosis and progression, and as a valuable target for breast cancer therapy.


Assuntos
Neoplasias da Mama/genética , Estradiol/metabolismo , Receptor alfa de Estrogênio/genética , RNA Longo não Codificante/biossíntese , Neoplasias da Mama/patologia , Proliferação de Células/genética , Sobrevivência Celular , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Células MCF-7 , RNA Longo não Codificante/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA