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1.
BMC Genomics ; 25(1): 443, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704563

RESUMO

BACKGROUND: The transcriptome and metabolome dissection of the skeletal muscle of high- and low- growing individuals from a crossbred population of the indigenous Chongming white goat and the Boer goat were performed to discover the potential functional differentially expressed genes (DEGs) and differential expression metabolites (DEMs). RESULTS: A total of 2812 DEGs were detected in 6 groups at three time stages (3,6,12 Month) in skeletal muscle using the RNA-seq method. A DEGs set containing seven muscle function related genes (TNNT1, TNNC1, TNNI1, MYBPC2, MYL2, MHY7, and CSRP3) was discovered, and their expression tended to increase as goat muscle development progressed. Seven DEGs (TNNT1, FABP3, TPM3, DES, PPP1R27, RCAN1, LMOD2) in the skeletal muscle of goats in the fast-growing and slow-growing groups was verified their expression difference by reverse transcription-quantitative polymerase chain reaction. Further, through the Liquid chromatography-mass spectrometry (LC-MS) approach, a total of 183 DEMs in various groups of the muscle samples and these DEMs such as Queuine and Keto-PGF1α, which demonstrated different abundance between the goat fast-growing group and slow-growing group. Through weighted correlation network analysis (WGCNA), the study correlated the DEGs with the DEMs and identified 4 DEGs modules associated with 18 metabolites. CONCLUSION: This study benefits to dissection candidate genes and regulatory networks related to goat meat production performance, and the joint analysis of transcriptomic and metabolomic data provided insights into the study of goat muscle development.


Assuntos
Cabras , Carne , Músculo Esquelético , Transcriptoma , Animais , Cabras/genética , Cabras/metabolismo , Músculo Esquelético/metabolismo , Carne/análise , Metabolômica , Perfilação da Expressão Gênica , Metaboloma
2.
Crit Rev Food Sci Nutr ; : 1-12, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38189321

RESUMO

As one of main culprit of seafood-associated human illness, Vibrio parahaemolyticus can readily accumulate on biotic or abiotic surfaces to form biofilms in the seafood processing environment. Biofilm formation on various surfaces can provide a protective barrier for viable bacterial cells that are resistant to most traditional bacteriostatic measures. This underscores the necessity and urgency of developing effective alternative strategies to control V. parahaemolyticus biofilms. Plants have always provided an extensive and infinite source of biologically active compounds for "green" antibiofilm agents. This review summarizes recent developments in promising multitargeted phytogenic compounds against V. parahaemolyticus biofilms. This review provides valuable insights into potential research targets that can be pursued further to identify potent natural antibiofilm agents in the food industry.

3.
Lett Appl Microbiol ; 77(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38886121

RESUMO

Hafnia sp. was one of the specific spoilage bacteria in aquatic products, and the aim of the study was to investigate the inhibition ability of the silver nanoparticles (AgNPs) biosynthesis by an aqueous extract of Prunus persica leaves toward the spoilage-related virulence factors of Hafnia sp. The synthesized P-AgNPs were spherical, with a mean particle size of 36.3 nm and zeta potential of 21.8 ± 1.33 mV. In addition, the inhibition effects of P-AgNPs on the growth of two Hafnia sp. strains and their quorum sensing regulated virulence factors, such as the formation of biofilm, secretion of N-acetyl-homoserine lactone (AHLs), proteases, and exopolysaccharides, as well as their swarming and swimming motilities were evaluated. P-AgNPs had a minimum inhibitory concentration (MIC) of 64 µg ml-1 against the two Hafnia sp. strains. When the concentration of P-AgNPs was below MIC, it could inhibit the formation of biofilms by Hafnia sp at 8-32 µg ml-1, but it promoted the formation of biofilms by Hafnia sp at 0.5-4 µg ml-1. P-AgNPs exhibited diverse inhibiting effects on AHLs and protease production, swimming, and swarming motilities at various concentrations.


Assuntos
Antibacterianos , Biofilmes , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Extratos Vegetais , Folhas de Planta , Prunus persica , Percepção de Quorum , Prata , Percepção de Quorum/efeitos dos fármacos , Prata/farmacologia , Prata/química , Prata/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Folhas de Planta/microbiologia , Folhas de Planta/química , Nanopartículas Metálicas/química , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Antibacterianos/farmacologia , Prunus persica/microbiologia , Aizoaceae/química , Fatores de Virulência/metabolismo
4.
Sensors (Basel) ; 23(23)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38067781

RESUMO

As space resources become increasingly constrained, the major space-faring nations are establishing large space target monitoring systems. There is a demand for both the number and the detection capability of space-based optical monitoring equipment. The detection range (i.e., field of view) and parasitic capability (lightweight and small size) of a single optical payload will largely reduce the scale and cost of the monitoring system. Therefore, in this paper, the optic-mechanical system of an ultra-lightweight and ultra-compact space camera and the optical alignment method are investigated around a fully freeform off-axis triple-reversal large field of view (FOV) optical system. The optic-mechanical system optimisation design is completed by adopting the optic-mechanical integration analysis method, and the weight of the whole camera is less than 10 kg. In addition, to address the mounting problems caused by the special characteristics of the freeform surface optical system, a dual CGH coreference alignment method is innovatively proposed. The feasibility of the method is verified by the mounting and testing test, and the test results show that the system wavefront difference is better than 1/10 λ. The imaging test of the space camera and the magnitude test results meet the design requirements of the optical system. The optic-mechanical system design method and alignment method proposed in this paper are instructive for the design and engineering of large field of view full freeform optical loads.

5.
Mol Reprod Dev ; 88(6): 427-436, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34032339

RESUMO

Mitochondrial dysfunction is considered a crucial factor aggravating oocyte viability after vitrification-warming. To clarify the role of mitophagy in mitochondrial extinction of vitrified porcine oocytes, mitochondrial function, ultrastructural characteristics, mitochondria-lysosomes colocalization, and mitophagic proteins were detected with or without chloroquine (CQ) treatment. The results showed that vitrification caused mitochondrial dysfunction, including increasing reactive oxygen species production, decreasing mitochondrial membrane potential, and mitochondrial DNA copy number. Damaged mitochondrial cristae and mitophagosomes were observed in vitrified oocytes. A highly fused fluorescence distribution of mitochondria and lysosomes was also observed. In the detection of mitophagic flux, mitophagy was demonstrated as increasing fluorescence aggregation of microtubule-associated protein light chain 3B (LC3B), enhanced colocalization between LC3B, and voltage-dependent anion channels 1 (VDAC1), and upregulated LC3B-II/I protein expression ratio. CQ inhibited the degradation of mitophagosomes in vitrified oocytes, manifested as decreased mitochondria-lysosomes colocalization, increased fluorescence fraction of VDAC1 overlapping LC3B, increased LC3B-II/I protein expression ratio, and p62 accumulation. The inhibition of mitophagosomes degradation by CQ aggravated mitochondrial dysfunction, including increased oxidative damage, reduced mitochondrial function, and further led to loss of oocyte viability and developmental potentiality. In conclusion, mitophagy is involved in the regulation of mitochondrial function during porcine oocyte vitrification.


Assuntos
Mitofagia , Oócitos/fisiologia , Vitrificação , Animais , Cloroquina/farmacologia , Cloroquina/toxicidade , Criopreservação/métodos , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Lisossomos/efeitos dos fármacos , Lisossomos/ultraestrutura , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Proteínas Associadas aos Microtúbulos/análise , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Mitofagia/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Oócitos/ultraestrutura , Fagossomos/efeitos dos fármacos , Fagossomos/ultraestrutura , Preservação Biológica/métodos , Espécies Reativas de Oxigênio/metabolismo , Suínos , Canal de Ânion 1 Dependente de Voltagem/análise
6.
Knowl Inf Syst ; 63(10): 2693-2718, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34465934

RESUMO

Stock market prediction is extremely important for investors because knowing the future trend of stock prices will reduce the risk of investing capital for profit. Therefore, seeking an accurate, fast, and effective approach to identify the stock market movement is of great practical significance. This study proposes a novel turning point prediction method for the time series analysis of stock price. Through the chaos theory analysis and application, we put forward a new modeling approach for the nonlinear dynamic system. The turning indicator of time series is computed firstly; then, by applying the RVFL-GMDH model, we perform the turning point prediction of the stock price, which is based on the fractal characteristic of a strange attractor with an infinite self-similar structure. The experimental findings confirm the efficacy of the proposed procedure and have become successful for the intelligent decision support of the stock trading strategy. Supplementary Information: The online version contains supplementary material available at 10.1007/s10115-021-01602-3.

7.
PLoS Comput Biol ; 15(2): e1006772, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30779739

RESUMO

Recent advances in next-generation sequencing and computational technologies have enabled routine analysis of large-scale single-cell ribonucleic acid sequencing (scRNA-seq) data. However, scRNA-seq technologies have suffered from several technical challenges, including low mean expression levels in most genes and higher frequencies of missing data than bulk population sequencing technologies. Identifying functional gene sets and their regulatory networks that link specific cell types to human diseases and therapeutics from scRNA-seq profiles are daunting tasks. In this study, we developed a Component Overlapping Attribute Clustering (COAC) algorithm to perform the localized (cell subpopulation) gene co-expression network analysis from large-scale scRNA-seq profiles. Gene subnetworks that represent specific gene co-expression patterns are inferred from the components of a decomposed matrix of scRNA-seq profiles. We showed that single-cell gene subnetworks identified by COAC from multiple time points within cell phases can be used for cell type identification with high accuracy (83%). In addition, COAC-inferred subnetworks from melanoma patients' scRNA-seq profiles are highly correlated with survival rate from The Cancer Genome Atlas (TCGA). Moreover, the localized gene subnetworks identified by COAC from individual patients' scRNA-seq data can be used as pharmacogenomics biomarkers to predict drug responses (The area under the receiver operating characteristic curves ranges from 0.728 to 0.783) in cancer cell lines from the Genomics of Drug Sensitivity in Cancer (GDSC) database. In summary, COAC offers a powerful tool to identify potential network-based diagnostic and pharmacogenomics biomarkers from large-scale scRNA-seq profiles. COAC is freely available at https://github.com/ChengF-Lab/COAC.


Assuntos
Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Algoritmos , Sequência de Bases/genética , Análise por Conglomerados , Análise de Dados , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Genoma , Sequenciamento de Nucleotídeos em Larga Escala , RNA Citoplasmático Pequeno/genética , Curva ROC , Software
8.
Cryobiology ; 92: 146-150, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31883445

RESUMO

This study aimed to investigate the effects of different concentrations of soybean lecithin (SL; 0.5%, 1%, and 1.5%) and egg yolk (EY) in Tris-based extenders on the semen quality parameters of post-thawed goat semen. Sixteen ejaculates were collected from eight healthy, mature Chongming White goats (3-5 years of age). Each ejaculate was divided into five equal aliquots, and then each pellet was diluted with one of the five Tris-based extenders containing 20% EY, 0.5% SL, 1% SL, 2% SL, or 3% SL. The cooled diluted semen was loaded into 0.5 mL polyvinyl French straws and cryopreserved in liquid nitrogen. Frozen semen samples were thawed at 37 °C and assessed for sperm motility, viability, plasma acrosome integrity, membrane integrity, and mitochondria integrity, and the spermatozoa were assessed for reactive oxygen species (ROS), superoxide dismutase (SOD), and malondialdehyde (MDA). The semen extended in the 2.0% SL extract tended to have a higher sperm viability (57.44%), motility (52.14%), membrane integrity (45.31%), acrosome integrity (52.96%), and mitochondrial activity (50.21%) than the other SL-based extender concentrations (P < 0.05). The 2.0% SL treatment group was equivalent to the semen extended in 20% EY (P > 0.05). The extenders supplemented 20% EY or 2.0% SL significantly increased the SOD activity and decreased the ROS and MDA activities compared to the other groups (P < 0.05). In conclusion, the extenders supplemented with 20% EY and 2.0% SL had similar effects on spermatozoa preservation. These results indicate that a soybean lecithin-based diluent may be used as an alternative extender to egg yolk for the cryopreservation of goat semen.


Assuntos
Gema de Ovo/química , Lecitinas/farmacologia , Análise do Sêmen/veterinária , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides/efeitos dos fármacos , Acrossomo/efeitos dos fármacos , Animais , Criopreservação/métodos , Congelamento , Cabras , Masculino , Malondialdeído/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sêmen/efeitos dos fármacos , Glycine max/química , Espermatozoides/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Trometamina/farmacologia
9.
Cryobiology ; 97: 71-75, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33039371

RESUMO

The aim of this study was to evaluate the interaction of different concentrations of butylated hydroxytoluene (BHT) in a tris-based extender on semen quality parameters in post-thawed dog semen. Twenty-four ejaculates were collected from eight male Beagle dogs using an artificial vagina. Pooled semen was diluted with a tris-based extender supplemented with 0 (control), 0.5, 1.0, 1.5, and 2.0 mM BHT, at a final concentration of 200 × 106 spermatozoa/mL. After thawing, sperm samples were assessed for motility parameters (CASA), membrane integrity (SYBR-14/PI), acrosome integrity (FITC-PNA), mitochondrial activity (JC-1/PI), malondialdehyde (MDA) concentration, and glutathione peroxidase (GPx) activity. The total motility, progressive motility, and average path velocity of the frozen-thawed sperm were significantly higher in the BHT1.5 group than in the control and the other sample groups (P < 0.05). Higher values of straight-line velocity, curvilinear velocity, amplitude of the lateral head displacement, and linearity were observed in the BHT1.0, BHT1.5, and BHT2.0 groups than in the control (P < 0.05). The BHT1.0 and BHT1.5 groups had higher percentages of straightness and acrosome integrity than the other groups (P < 0.05). Beat cross frequency, plasma membrane integrity, and GPx activity of the BHT1.5 and BHT2.0 groups were higher than those of the control (P < 0.05). A lower concentration of MDA was observed in the BHT1.0, BHT1.5, and BHT2.0 groups than in the control (BHT0) (P < 0.05). Our results indicate that 1.5 mM BHT is the optimal concentration for improving the post-thaw quality of canine spermatozoa.


Assuntos
Hidroxitolueno Butilado , Preservação do Sêmen , Acrossomo , Animais , Hidroxitolueno Butilado/farmacologia , Criopreservação/métodos , Crioprotetores/farmacologia , Cães , Masculino , Análise do Sêmen , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides
10.
Sleep Breath ; 24(4): 1383-1388, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31832981

RESUMO

PURPOSE: To study and analyze the sleep quality and sleep structure of patients with vestibular migraine (VM). METHODS: In this cross-sectional case-control study, the Pittsburgh Sleep Quality Index (PSQI) questionnaire and polysomnography (PSG) were used to compare the clinical characteristics of sleep disorders in 49 patients with VM, 52 patients with migraine, and 54 controls. RESULTS: The VM, migraine, and control groups did not significantly differ in terms of age or sex. Compared with the migraine and control groups, the VM group had a higher incidence of poor sleep quality (χ2 = 36.618, p < 0.01) and greater severity of poor sleep quality (p < 0.01). Furthermore, the VM group showed reduced sleep efficiency (p < 0.01) and reduced proportions of REM and slow wave (N3) sleep (p ≤ 0.01). Conversely, sleep latency (p = 0.01) and REM latency (p = 0.04) were prolonged, and proportions of light sleep phases (N1, p < 0.05, and N2, p < 0.01) and the micro-arousal index (p = 0.03) were increased. The migraine group had significantly higher apnea hypopnea (AHI) and periodic leg movement (PLMI) indices than the VM group. CONCLUSION: We report an effect of VM on sleep structure and an association with migraine. Similar to migraine, VM affects the sleep regulation centers and causes structural sleep disorders.


Assuntos
Transtornos de Enxaqueca/fisiopatologia , Transtornos do Sono-Vigília/fisiopatologia , Doenças Vestibulares/fisiopatologia , Adulto , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/complicações , Transtornos de Enxaqueca/epidemiologia , Polissonografia , Transtornos do Sono-Vigília/complicações , Transtornos do Sono-Vigília/epidemiologia , Inquéritos e Questionários , Doenças Vestibulares/complicações , Doenças Vestibulares/epidemiologia
11.
Sensors (Basel) ; 20(9)2020 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-32370109

RESUMO

The piezoelectric actuator is indispensable for driving the micro-manipulator. In this paper, a simplified interval type-2 (IT2) fuzzy system is proposed for hysteresis modelling and feedforward control of a piezoelectric actuator. The partial derivative of the output of IT2 fuzzy system with respect to the modelling parameters can be analytically computed with the antecedent part of IT2 fuzzy rule specifically designed. In the experiments, gradient based optimization was used to identify the IT2 fuzzy hysteresis model. Results showed that the maximum error of model identification is 0.42% with only 3 developed IT2 fuzzy rules. Moreover, the model validation was conducted to demonstrate the generalization performance of the identified model. Based on the analytic inverse of the developed model, feedforward control experiment for tracking sinusoidal trajectory of 20 Hz was carried out. As a result, the hysteresis effect of the piezoelectric actuator was reduced with the maximum tracking error being 4.6%. Experimental results indicated an improved performance of the proposed IT2 fuzzy system for hysteresis modelling and feedforward control of the piezoelectric actuator.

12.
J Sci Food Agric ; 100(7): 3246-3256, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32124447

RESUMO

BACKGROUND: As the primary food for nearly half of the world's population, rice is cultivated almost all over the world, especially in Asian countries. However, the farmers and planting experts have been facing many persistent agricultural challenges for centuries, such as different diseases of rice. The severe rice diseases may lead to no harvest of grains; therefore, a fast, automatic, less expensive and accurate method to detect rice diseases is highly desired in the field of agricultural information. RESULTS: In this article, we study the deep learning approach for solving the task since it has shown outstanding performance in image processing and classification problem. Combining the advantages of both, the DenseNet pre-trained on ImageNet and Inception module were selected to be used in the network, and this approach presents a superior performance with respect to other state-of-the-art methods. It achieves an average predicting accuracy of no less than 94.07% in the public dataset. Even when multiple diseases were considered, the average accuracy reaches 98.63% for the class prediction of rice disease images. CONCLUSIONS: The experimental results prove the validity of the proposed approach, and it is accomplished efficiently for rice disease detection. © 2020 Society of Chemical Industry.


Assuntos
Aprendizado Profundo , Oryza/química , Doenças das Plantas , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação
13.
Reprod Domest Anim ; 54(12): 1604-1611, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31549747

RESUMO

Aberration in DNA methylation is believed to be one of the major causes of abnormal gene expression and inefficiency of somatic cell nuclear transfer (SCNT). RG108, a non-nucleoside DNA methyltransferase (DNMT) inhibitor, has been reported to facilitate somatic nuclear reprogramming and improved blastocyst formation. The aim of this study was to investigate interaction effect of RG108 treatment time (24-72 hr) and concentrations (0.05-50 µM) on donor cells, and further to optimize the treatment for porcine SCNT. Our results showed that RG108 treatment resulted in time-dependent decrease of genome-wide DNA methylation on foetal fibroblasts, which only happened after 72-hr treatment in our experiments, and no interaction effect between treatment time and concentration. Remarkable decrease of methylation in imprinted gene H19 and increased apoptosis was observed in 5 and 50 µM RG108-treated cells. Furthermore, the blastocyst rates of SCNT embryos were increased as the fibroblasts treated with RG108 at 5 and 50 µM, and additional treatment during cultivation of SCNT embryos would not provide any advantage for blastocyst formation. In conclusion, the RG108 treatment of 72 hr and 5 µM would be optimized time and concentration for porcine foetal fibroblasts to improve the SCNT embryonic development. In addition, combined treatment of RG108 on donor cells and SCNT embryos would not be beneficial for embryonic development.


Assuntos
DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , Metilação de DNA/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Histonas/metabolismo , Técnicas de Transferência Nuclear/veterinária , Ftalimidas/farmacologia , Triptofano/análogos & derivados , Animais , Blastocisto/citologia , Blastocisto/efeitos dos fármacos , Reprogramação Celular/efeitos dos fármacos , Embrião de Mamíferos , Desenvolvimento Embrionário/efeitos dos fármacos , Epigênese Genética , Feminino , Fibroblastos/citologia , Suínos , Triptofano/farmacologia
14.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 35(1): 123-130, 2018 02 25.
Artigo em Chinês | MEDLINE | ID: mdl-29745611

RESUMO

In order to reduce osmotic damage and chemical toxicity of cryoprotectants (CPA) to oocytes during unloading process, the microfluidic chip was used to remove CPA from porcine MⅡ oocytes in this study. Firstly, the effects of unloading time, composition and concentration of diluting solutions of microfluidic method on survival rate and developmental capacity of oocytes were studied, then microfluidic method was compared with traditional one-step and two-step CPA unloading protocols. The results showed that when the total time is 8 minutes, the survival rate and morula rate of oocytes treated with microfluidic method could achieve 95.99% ± 4.64% and 74.17% ± 1.18%, respectively, which were not significantly different from fresh control group (98.53% ± 2.94%; 78.22% ± 1.34%). In addition, 1 mol/L sucrose diluting solutions were more beneficial than other solutions, and it was also showed that microfluidic method achieved better survival, cleavage rate of oocytes than traditional methods. Microfluidic CPA removal protocol can reduce the damage to oocytes during unloading process, and may further improve the cryopreservation effect of oocytes.

15.
J Food Sci Technol ; 55(9): 3703-3711, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30150830

RESUMO

The antifungal effect of Lactobacillus plantarum C10 on pink rot caused by Trichothecium roseum and its application in muskmelon fruit were investigated. Cell-free supernatant (CFS) produced by Lactobacillus plantarum C10 strongly inhibited the growth of T. roseum and seriously damaged the structures of spores and mycelia of T. roseum. Acid compounds produced by Lb. plantarum C10 were the major antifungal substances and exhibited a narrow pH range from 3.5 to 6.5. Application of the CFS on muskmelon fruit reduced the contamination zone of T. roseum by enhancing the activities of defensive enzymes (phenylalanine ammonialyase, peroxidase and polyphenoloxidase) and promoting the accumulation of phenolics and flavonoids. These results suggested that Lb. plantarum C10 could be used as a biocontrol agent to control pink rot caused by T. roseum in muskmelon fruit.

16.
Sensors (Basel) ; 17(4)2017 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-28398244

RESUMO

To improve the phase-shifting accuracy, this paper presents a novel integrated framework for design, control and experimental validation of the piezoelectric actuated phase shifter with a trade-off between accuracy and cost. The piezoelectric actuators with built-in sensors are adopted to drive the double parallel four-bar linkage flexure hinge-based mechanisms. Three mechanisms form the tripod structure of the assembled phase shifter. Then, a semi-closed loop controller with inner feedback and outer feedforward loops via the external laser interferometer is developed for accurate positioning of the phase shifter. Finally, experiments related with travel range, step response, linearity and repeatability are carried out. The linearity error is 0.21% and the repeatability error of 10 µ m displacement is 3 nm. The results clearly demonstrate the good performance of the developed phase shifter and the feasibility of the proposed integrated framework.

17.
Cryo Letters ; 37(3): 188-95, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27393955

RESUMO

BACKGROUND: The developmental potential of vitrified porcine oocytes is very lower, and apoptosis is considered as one of the key factors involved. OBJECTIVE: To investigate the effects of apoptotic inhibitor Z-VAD-FMK addition into the incubation medium after warming on apoptosis and developmental ability of vitrified porcine MII-stage oocytes. MATERIALS AND METHODS: The activities of several caspases, mitochondrial membrane potential (ΔΨm) and early apoptotic levels were measured. Parthenogenetic developmental ability and relative expression levels of apoptosis related genes were also detected. RESULTS: Caspase activity and early apoptotic level of the Z-VAD-FMK group were significantly lower than those of the group without Z-VAD-FMK addition, but were much higher than those of fresh group (P < 0.05). The ΔΨm of Z-VAD-FMK group was 1.19, higher than the vitrified group (0.91) and lower than the fresh group (1.33). The cleavage rate and blastocyst rate after parthenogenetic activation in the Z-VAD-FMK group were much higher than those in the vitrified group, and much lower than those in the fresh group (P < 0.05). Vitrified porcine oocytes exhibited increased expression of pro-apoptotic genes (caspase 3, 8, 9, TNF-α) and decreased genes expression levels of anti-apoptotic genes (Bcl-2, CuZnSOD), and the Z-VAD-FMK addition in incubaiton medium significantly decreased the transcripts levels of caspase 3,8,9, Bax, TNF-α and increased Bcl-2 and CuZnSOD genes expression. CONCLUSION: The addition of apoptotic inhibitor Z-VAD-FMK into the incubation medium after warming improved the in vitro developmental ability of vitrified porcine oocytes by increasing mitochondrial function, reducing apoptotic level and changing apoptosis-elated gene expression.


Assuntos
Clorometilcetonas de Aminoácidos/farmacologia , Apoptose/efeitos dos fármacos , Criopreservação , Oócitos , Suínos , Animais , Calefação , Vitrificação
18.
J Theor Biol ; 369: 51-8, 2015 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-25636491

RESUMO

Polymerase chain reaction (PCR) is hailed as one of the monumental scientific techniques of the twentieth century, and has become a common and often indispensable technique in many areas. However, researchers still frequently find some DNA templates very hard to amplify with PCR, although many kinds of endeavors were introduced to optimize the amplification. In fact, during the past decades, the experimental procedure of PCR was always the focus of attention, while the analysis of a DNA template, the PCR experimental subject itself, was almost neglected. Up to now, nobody can certainly identify whether a fragment of DNA can be simply amplified using conventional Taq DNA polymerase-based PCR protocol. Characterizing a DNA template and then developing a reliable and efficient method to predict the success of PCR reactions is thus urgently needed. In this study, by means of the Markov maximal order model, we construct a 48-D feature vector to represent a DNA template. Support vector machine (SVM) is then employed to help evaluate PCR result. To examine the anticipated success rates of our predictor, jackknife cross-validation test is adopted. The overall accuracy of our approach arrives at 93.12%, with the sensitivity, specificity, and MCC of 94.68%, 91.58%, and 0.863%, respectively.


Assuntos
Cadeias de Markov , Reação em Cadeia da Polimerase/métodos , Máquina de Vetores de Suporte , Humanos , Modelos Teóricos
19.
Cryobiology ; 71(2): 291-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26247316

RESUMO

The purpose of this study was to investigate the changes in mitochondria in porcine MII-stage oocytes after open pulled straw (OPS) vitrification and to determine their roles in apoptosis and in vitro developmental ability. The mitochondrial membrane potential (ΔΨm), reactive oxygen species (ROS) level, adenosine-5'-triphosphate (ATP) concentration, mitochondrial distribution, mitochondrial ultrastructure, early-stage apoptosis with Annexin V-FITC staining, survival rate, parthenogenetic developmental ability and related gene expression were measured in the present experiments. The results showed that: (1) the mitochondrial ΔΨm of vitrified-thawed oocytes (1.05) was lower than that of fresh oocytes 1.24 (P<0.05). (2) ROS level in the OPS vitrification group was much higher than that of the fresh group, while the ATP concentration was much lower than that of fresh group (P<0.05). (3) Early-stage apoptosis rate from the OPS vitrification group (57.6%) was much higher than that of fresh group (8.53%) (P<0.05), and the survival rate and parthenogenetic cleavage rate of OPS vitrified oocytes were much lower than those from fresh ones (P<0.05). (4) Vitrification not only disrupted the mitochondrial distribution of porcine MII-stage oocytes, but also damaged the mitochondrial ultrastructure. (5) After vitrification, the gene expression level of Dnm1 was up-regulated, and other four genes (SOD1, Mfn2, BAX and Bcl2) were down-regulated. The present study suggested that not only the morphology and function of mitochondria were damaged greatly during the vitrification process, but also early-stage apoptosis was observed after vitrification. Intrinsic mitochondrial pathway could be in involved in the occurrence of apoptosis in vitrified-thawed porcine oocytes.


Assuntos
Apoptose/fisiologia , Criopreservação/métodos , Mitocôndrias/patologia , Oócitos/metabolismo , Suínos/fisiologia , Vitrificação , Trifosfato de Adenosina/metabolismo , Animais , Feminino , Potencial da Membrana Mitocondrial/fisiologia , Mitocôndrias/fisiologia , Oócitos/citologia , Partenogênese , Espécies Reativas de Oxigênio/metabolismo
20.
Luminescence ; 30(8): 1389-94, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25866153

RESUMO

A highly sensitive fluorescence method for glycoprotein detection has been established based on fluorescence resonance energy transfer (FRET) between CuInS2 quantum dots (QDs) and rhodamine B (RB). Lectins comprise a group of proteins with unique affinities toward carbohydrate structures, so the process of FRET can occur between lectin-coated QDs (CuInS2 QDs-Con A conjugates, acceptors) and carbohydrate-coated RB (RB-NH2-glu conjugates, donors). The fluorescence of lectin-coated QDs was recovered in the presence of a glycoprotein such as glucose oxidase (GOx) and transferrin (TRF), which significantly reduced the FRET efficiency between the donor and the acceptor. Under optimal conditions, a linear correlation was established between the fluorescence intensity ratio I654/I577 and the TRF concentration over the range of 6.90 × 10(-10) to 3.45 × 10(-8) mol/L, with a detection limit of 2.5 × 10(-10) mol/L. The linear range for GOx is 3.35 × 10(-10) to 6.70 × 10(-8) mol/L, with a detection limit of 1.5 × 10(-10) mol/L. The proposed method was applied to the determination of glycoprotein in human serum and cell-extract samples with satisfactory results. Furthermore, CuInS2 QDs-Con A conjugates are used as safe and efficient optical nanoprobes in HepG2 cell imaging.


Assuntos
Transferência Ressonante de Energia de Fluorescência/métodos , Corantes Fluorescentes/química , Glicoproteínas/química , Pontos Quânticos/química , Rodaminas/química , Células Hep G2 , Humanos , Lectinas/química , Limite de Detecção , Ligação Proteica
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