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1.
Sensors (Basel) ; 23(5)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36904672

RESUMO

The vacuum degree is the key parameter reflecting the quality and performance of vacuum glass. This investigation proposed a novel method, based on digital holography, to detect the vacuum degree of vacuum glass. The detection system was composed of an optical pressure sensor, a Mach-Zehnder interferometer and software. The results showed that the deformation of monocrystalline silicon film in an optical pressure sensor could respond to the attenuation of the vacuum degree of vacuum glass. Using 239 groups of experimental data, pressure differences were shown to have a good linear relationship with the optical pressure sensor's deformations; pressure differences were linearly fitted to obtain the numerical relationship between pressure difference and deformation and to calculate the vacuum degree of the vacuum glass. Measuring the vacuum degree of vacuum glass under three different conditions proved that the digital holographic detection system could measure the vacuum degree of vacuum glass quickly and accurately. The optical pressure sensor's deformation measuring range was less than 4.5 µm, the measuring range of the corresponding pressure difference was less than 2600 pa, and the measuring accuracy's order of magnitude was 10 pa. This method has potential market applications.

2.
Curr Diabetes Rev ; 19(7): e160123212750, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36650624

RESUMO

BACKGROUND: Diabetes has become a problem that plagues public healthcare systems. Recent studies have shown that intestinal flora exerts positive therapeutic effects on metabolic diseases, and plant-derived secondary metabolites are safe, effective and easy to prepare and also have an impact on intestinal flora and diabetes; these drugs have rarely been reviewed before as a class of drugs for diabetes, especially focusing on the intestinal flora. Therefore, studying the relationship between plant-derived secondary metabolites and diabetes mellitus is crucial. OBJECTIVE: The objective of this study is to summarize and investigate the therapeutic mechanism of drugs extracted from natural plants effects on type 2 diabetes mellitus. METHODS: The relationship between flora and type 2 diabetes was investigated by reviewing the recent experimental literature, and the pathways available for natural plant-derived secondary metabolites in the treatment of type 2 diabetes were summarized. RESULTS: The therapeutic mechanisms of common plant-derived secondary metabolites for type 2 diabetes were summarized with a focus on the prebiotic efficacy of natural plant-derived secondary metabolites and the modulation of intestinal flora, and the mechanisms through which plantderived secondary metabolites treat type 2 diabetes via effects on intestinal flora are further reviewed. CONCLUSION: Common plant-derived secondary metabolites can play a role in regulating bacteria in the intestinal tract by enriching beneficial bacteria and removing harmful bacteria to achieve their therapeutic effect on type 2 diabetes. In addition, due to their excellent ability to regulate intestinal flora, plant-derived secondary metabolites may also have excellent efficacy in cancer and obesity, among other diseases.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Neoplasias , Humanos , Diabetes Mellitus Tipo 2/metabolismo
3.
Molecules ; 27(24)2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36557926

RESUMO

Advanced glycation end products (AGEs) cause damage to pancreatic ß-cells and trigger oxidative stress and inflammation, which promotes the development and progression of diabetes and its complications. Therefore, it is important to inhibit the formation of AGEs as part of the treatment of diabetes. Allicin is a natural antimicrobial agent with abundant pharmacological activities, and recent studies have reported its therapeutic effects in diabetes; however, the mechanism of these therapeutic effects is still unclear. Thus, the purpose of this study was to further investigate the association between allicin treatment of diabetes and AGEs. First, we established a streptozocin (STZ)-induced diabetic rat model and treated the rats with allicin for six weeks. We measured glycolipid metabolism, AGE levels, receptor of advanced glycation end products (RAGE) levels, oxidative stress, and other related indicators. The results showed that allicin improved blood glucose and body weight, reduced lipid accumulation, and inhibited AGE formation in rats. Treatment with allicin also inhibited RAGEs and thereby prevented AGE activity, which, in turn, alleviated oxidative stress and promoted insulin secretion. To further verify the effect of allicin on AGEs, we also performed in vitro nonenzymatic glycation simulation experiments. These results showed that allicin inhibited the production of AGEs by suppressing the production of AGEs intermediates. Thus, our research suggests that allicin may alleviate diabetes by inhibiting the formation of AGEs and reducing RAGE levels to relieve oxidative stress and promote insulin secretion.


Assuntos
Diabetes Mellitus Experimental , Produtos Finais de Glicação Avançada , Ratos , Animais , Produtos Finais de Glicação Avançada/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Ratos Wistar , Diabetes Mellitus Experimental/metabolismo , Estresse Oxidativo
4.
Opt Express ; 30(12): 20666-20683, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-36224806

RESUMO

Speckle denoising can improve digital holographic interferometry phase measurements but may affect experimental accuracy. A deep-learning-based speckle denoising algorithm is developed using a conditional generative adversarial network. Two subnetworks, namely discriminator and generator networks, which refer to the U-Net and DenseNet layer structures are used to supervise network learning quality and denoising. Datasets obtained from speckle simulations are shown to provide improved noise feature extraction. The loss function is designed by considering the peak signal-to-noise ratio parameters to improve efficiency and accuracy. The proposed method thus shows better performance than other denoising algorithms for processing experimental strain data from digital holography.

5.
Biomed Pharmacother ; 140: 111750, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34051615

RESUMO

Advanced glycation end products (AGEs) are a group of complex compounds generated by nonenzymatic interactions between proteins and reducing sugars or lipids. AGEs accumulate in vivo and activate various signaling pathways closely related to the occurrence of various chronic metabolic diseases. In this paper, we describe the process through which AGEs are formed, the classification of AGEs, and biological effects of AGEs on human health. Most importantly, we review recent progress in natural compound-based AGE formation inhibitors. Major classes of natural inhibitors, including polyphenols, polysaccharides, terpenoids, vitamins and alkaloids, have been described. Their mechanisms of action have been summarized as scavenging free radicals, chelating metal ions, capturing active carbonyl compounds, protecting protein glycation sites, and lowering blood glucose levels. Although these natural compounds have good antiglycation activity, to date, they are not widely used in the clinic, likely because of their low content levels. However, these natural compounds and their molecular frameworks will play a valuable role in inspiring drug discovery.


Assuntos
Produtos Biológicos/farmacologia , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Animais , Produtos Finais de Glicação Avançada/metabolismo , Humanos
6.
Biomed Res Int ; 2020: 8126176, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32714986

RESUMO

OBJECTIVE: An ideal sample source is critical for more reliable and sensitive early detection of nucleic acid changes associated with breast cancer. Breast milk (BM) is a good noninvasive origin for genetic testing of early breast cancer, but cells in BM are easily disintegrated. So we investigate here whether cell-free nucleic acid (cfNA) exists in BM in a more stable form and whether the quality of BM cfNA is good enough for genetic testing. METHODS: A self-designed qRT-PCR method was used to measure the existence and abundance of cfDNA. Quality of cfDNA and cfRNA were detected by capillary electrophoresis. Whole genome bisulfite sequencing and miRNA sequencing were used to explore the sources of cfDNA and cell-free miRNA in BM. The copy number analysis and z-test based on whole genome sequencing data were used to determine the integrity of genetic information in BM cfNA. RESULTS: We found that cell-free DNA and miRNA exist in the studied breast milk samples in a stable form that can tolerate incubation of BM at room temperature for at least 7 days. These cell-free nucleic acids come mainly from breast-derived cells and contain genetic information as good integrity as in BM cells. We further listed some candidate miRNAs as potential biomarkers for research of early breast cancer screening by analysis of previous reports and our data. CONCLUSIONS: Our results suggest that cfDNA and cell-free miRNA in BM might be new noninvasive sample sources for finding early alterations of nucleic acid associated with the initiation and progression of breast cancer.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Ácidos Nucleicos Livres/metabolismo , Detecção Precoce de Câncer , MicroRNAs/metabolismo , Leite Humano/metabolismo , Sequência de Bases , Biomarcadores Tumorais/genética , Mama/patologia , Ácidos Nucleicos Livres/genética , Feminino , Regulação da Expressão Gênica , Genoma Humano , Humanos , Estabilidade de RNA/genética , Temperatura
7.
PLoS One ; 10(3): e0120790, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25811979

RESUMO

The Yes-associated protein (YAP), a transcriptional coactivator inactivated by the Hippo tumor suppressor pathway, functions as an oncoprotein in a variety of cancers. However, its contribution to breast cancer remains controversial. This study investigated the role of YAP in breast cancer cells under nutrient deprivation (ND). Here, we show that YAP knockdown sensitized MCF7 breast cancer cells to nutrient deprivation-induced apoptosis. Furthermore, in response to ND, YAP increased the autolysosome degradation, thereby enhancing the cellular autophagic flux in breast cancer cells. Of note, autophagy is crucial for YAP to protect MCF7 cells from apoptosis under ND conditions. In addition, the TEA domain (TEAD) family of growth-promoting transcription factors was indispensable for YAP-mediated regulation of autophagy. Collectively, our data reveal a role for YAP in promoting breast cancer cell survival upon ND stress and uncover an unappreciated function of YAP/TEAD in the regulation of autophagy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias da Mama/metabolismo , Fosfoproteínas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Apoptose/genética , Autofagia/genética , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Feminino , Técnicas de Silenciamento de Genes , Humanos , Lisossomos/metabolismo , Células MCF-7 , Fosfoproteínas/genética , Ligação Proteica , Fatores de Transcrição/metabolismo , Proteínas de Sinalização YAP
8.
J Opt Soc Am A Opt Image Sci Vis ; 28(6): 1262-75, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21643412

RESUMO

This paper presents an experimental investigation and an analytical modeling of the nonlinear pixel saturation effect in digital off-axis holography. The theoretical analysis is based on a semiempirical modeling and supported by the experimental analysis. Taking into account the nonlinearity of the phenomenon, an exponential law for the high-order harmonic amplitude is proposed and validated by the experimental results. The conclusion of this analysis is that the saturation effect can be described by the use of a linear operator that involves autoconvolution of the initial object wave, even though the saturation phenomenon is nonlinear.

9.
J Opt Soc Am A Opt Image Sci Vis ; 28(6): 1291-6, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21643415

RESUMO

In the research of digital holography, this paper presents a numerical method using an adjustable magnification for local object field reconstruction together with experiment verification. The method first designs a spherical wave according to the given magnification to illuminate the digital hologram, then through a Fourier transform of diffraction, it calculates the reconstructed image plane. Afterward, a filtering window is set in the image plane to extract the image of the local object field, and then the object field reached hologram plane is formed using diffraction's inverse operation. Finally, the object field is reconstructed through diffraction's angular spectrum theory.

10.
Opt Lett ; 35(12): 2055-7, 2010 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-20548384

RESUMO

This Letter presents a method for real-time 3D measurements based on three-color digital holographic interferometry. The optical setup is considerably simplified, since the reference beams are combined into a unique beam. A convolution algorithm allows the three monochrome images to be superposed to provide simultaneous full-field 3D measurements. Experimental results confirm the suitability of the proposed method.

11.
Biochem Biophys Res Commun ; 391(1): 267-71, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19913514

RESUMO

Treatment of mouse cells with lipopolysaccharide (LPS) potently initiates an inflammatory response, but the underlying mechanisms are unclear. We therefore sought to characterize cDNA sequences of a new mouse LPS-responsive gene, and to evaluate the effects of MLrg. Full-length cDNAs were obtained from LPS-treated NIH3T3 cells. We report that the MLrg gene produces two alternative splice products (GenBank Accession Nos. DQ316984 and DQ320011), respectively, encoding MLrgW and MLrgS polypeptides. Both proteins contain zinc finger and leucine zipper domains and are thus potential regulators of transcription. Expression of MLrgW and MLrgS were robustly upregulated following LPS treatment, and the proteins were localized predominantly in the nuclear membrane and cytoplasm. In stable transfectants over-expressing MLrgW the proportion of cells in G1 phase was significantly reduced, while in cells over-expressing MLrgS the proportion of cells in G2 was significantly increased; both proteins are thus potential regulators of cell cycle progression. Upregulation of MLrgW and MLrgS may be an important component of the LPS inflammatory pathway and of the host response to infection with GNB.


Assuntos
Processamento Alternativo , Proteínas de Transporte/metabolismo , Bactérias Gram-Negativas/imunologia , Inflamação/microbiologia , Zíper de Leucina , Lipopolissacarídeos/imunologia , Proteínas Nucleares/metabolismo , Dedos de Zinco , Animais , Proteínas de Transporte/genética , Clonagem Molecular , Proteínas Correpressoras , Inflamação/genética , Camundongos , Células NIH 3T3 , Proteínas Nucleares/genética , Regulação para Cima
12.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 22(3): 371-3, 376, 2006 May.
Artigo em Chinês | MEDLINE | ID: mdl-16643803

RESUMO

AIM: To express mouse lipopolysaccharide response protein (mLRP) and prepare rabbit anti-mLRP serum. METHODS: The predicted mouse lrp cDNA sequence was obtained by splicing homologous ESTs by comparing human lrp cDNA with mouse ESTs. Then the primers were designed. mlrp cDNA from NIH3T3 cells stimulated with lipopolysaccharide (LPS) was amplified by RT-PCR and was cloned into prokaryotic expression vector pTAT to construct recombinant expression vector pTAT-mlrp. The His-TAT-mLRP fusion protein was expressed in E. coli BL21(DE3) and was used to immunize the rabbits to get rabbit anti-mLRP serum. The anti-serum was purified by the acetone precipitation method. The specificity of the rabbit anti-mLRP serum was determined by Western blot. RESULTS: The predicted length of mlrp cDNA was 1905 bp. The encoding region of the cloned mlrp cDNA, 1554 bp, was inserted into pTAT. The His-TAT-mLRP fusion protein was expressed successfully in E. coli. The rabbit anti-mLRP serum was prepared by immunizing the rabbit with mLRP protein. CONCLUSION: The successful expression of mLRP and the preparation of rabbit anti-mLRP serum lays the foundation for further study of the function of mLRP.


Assuntos
Proteínas de Fase Aguda/imunologia , Formação de Anticorpos/imunologia , Proteínas de Transporte/imunologia , Escherichia coli/genética , Glicoproteínas de Membrana/imunologia , Proteínas Recombinantes/imunologia , Proteínas de Fase Aguda/genética , Proteínas de Fase Aguda/metabolismo , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Clonagem Molecular , Feminino , Expressão Gênica , Vetores Genéticos , Lipopolissacarídeos/química , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Células NIH 3T3 , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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