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1.
Zhonghua Nei Ke Za Zhi ; 60(11): 954-959, 2021 Nov 01.
Artigo em Chinês | MEDLINE | ID: mdl-34689515

RESUMO

Elderly diabetic patients in China accounts for one fourth of the total number of elderly diabetic patients in the world, ranking the first worldwide. In 2021, National Center of Gerontology, Chinese Society of Geriatrics and Diabetes Professional Committee of Chinese Aging Well Association issued China's first guideline on elderly diabetic patients--Guideline for the management of diabetes mellitus in the elderly in China (2021 edition). The present article interprets parts of the important recommendations of the guideline, aiming to facilitate its implementation in clinical practice effectively and improve the clinical prognosis of elderly diabetic patients in our country.


Assuntos
Diabetes Mellitus , Idoso , China , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/terapia , Humanos , Prognóstico
2.
Lett Appl Microbiol ; 73(5): 652-657, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34342880

RESUMO

Two polyurethanases PueA and PueB from Pseudomonas protegens Pf-5 have been reported to have hydrolytic activity against synthetic p-nitrophenyl palmitate of lipase substrate, and PueA may play a more effective role in this activity. However, it is still unknown whether PueA and PueB play similar parts in the lipase activity against natural acylglycerols and achieve the extracellular secretion via their cognate ABC exporter AprDEF. In this study, we investigated these questions through the construction of four markerless deletion mutants in Pf5139 (Δupp derivative of Pf-5), two heterologous co-expression strains and their three control strains in lipase-free Escherichia coli BL21(DE3), and detected their lipase activities by the tributyrin plate assay and the liquid culture assay. The results showed that PueA and PueB, classified as subfamily I.3 lipases, are major extracellular lipases involved in the uptake of oil in Pf-5, and PueA plays a leading role in extracellular lipase activity. In addition, the extracellular secretion of PueA and PueB can be partly mediated via AprDEF in Pf-5 and BL21(DE3). Finally, PueA and PueB are also able to achieve the extracellular secretion without the assistance of AprDEF in Pf-5 and BL21(DE3).


Assuntos
Proteínas de Bactérias , Pseudomonas , Proteínas de Bactérias/genética , Escherichia coli , Lipase/genética , Pseudomonas/genética
3.
Eur Rev Med Pharmacol Sci ; 24(6): 3130-3142, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32271431

RESUMO

OBJECTIVE: Chemoresistance is the leading cause of recurrence in non-small cell lung cancer (NSCLC). The long non-coding RNA (lncRNA) cancer susceptibility candidate 2 (CASC2) inhibits the tumorigenesis of various cancers. However, the regulatory function of CASC2 on the chemoresistance of NSCLC remains unclear. PATIENTS AND METHODS: The levels of CASC2 and miR-18a in cisplatin (DDP)-resistant NSCLC tissues and cell lines were evaluated by quantitative Polymerase Chain Reaction (qPCR). The role of low CASC2 levels on overall survival in patients with NSCLC was tested using the log-rank test. The Chi-squared test was used to assess the relation between CASC2 expression and clinicopathological features of NSCLC patients. Cell Counting Kit-8 (CCK-8) assays tested the cell proliferation of cisplatin-resistant NSCLC cells (H226/DDP and A549/DDP). The underlying regulatory mechanism between CASC2 and miR-18a or miR-18a and interferon regulatory factor 2 (IRF-2) was predicted by bioinformatics and verified by a Dual-Luciferase reporter assay, RNA transfection, qPCR, and Western blotting. Chromatin immunoprecipitation (ChIP) assay was done to exam the relation between E74 like factor 1 (ELF1) and CASC2 gene. Mice xenografts were applied to exam the function of CASC2 on chemosensitivity of cisplatin of NSCLC cells in vivo. RESULTS: Low CASC2 expression is more likely to present in patients with advanced TNM stage (IV), cisplatin-resistance, and poor overall survival. The expression of CASC2 sharply decreased in cisplatin-resistant NSCLC tissues and cell lines (H226/DDP and A549/DDP). CASC2 overexpression strongly inhibited proliferation, migration, and invasion of cisplatin-resistant NSCLC cells (H226/DDP and A549/DDP) in vitro and inhibited tumor growth in vivo. Besides, CASC2 repressed miR-18a function by binding to the complementary sites of miR-18a as competing endogenous RNAs (ceRNAs). MiR-18a released by the declining expression of CASC2 reduced the protein concentration of IRF-2 in NSCLC cells. Furthermore, the transcription factor ELF1 was found to be promotor of CASC2 and increased its levels in cisplatin-resistant NSCLC cells. CONCLUSIONS: IRF-2 expression mediated by the ELF1/CASC2/miR-18a axis is markedly associated with the proliferation, migration, and invasion of cisplatin-resistant NSCLC, resulting in inferior survival. These findings suggest that this regulatory axis may serve as a novel therapeutic target in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Fator Regulador 2 de Interferon/metabolismo , Neoplasias Pulmonares/metabolismo , MicroRNAs/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Fator Regulador 2 de Interferon/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética
4.
Opt Express ; 27(12): 17322-17347, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31252944

RESUMO

Although x-ray tomography is commonly used to characterize the three-dimensional structure of materials, sometimes this is impractical due either to limited time for data collection (such as in rapidly-evolving systems) or the need to limit the radiation exposure of the sample. In such situations, it is desirable to extract as much information as possible from a more limited data set. In this paper, we describe how to extract the size distribution of non-spherical pores (or, equivalently, particles) from single x-ray phase contrast imaging (XPCI). Because the pores overlap in projection, interpreting the images and extracting quantitative information about the size distribution is non-trivial. In this paper we extend a previously-developed Fourier-based framework for interpreting the speckle pattern of XPCI images from materials with spherical pores to the more challenging case of non-spherical pores. We develop an analytical expression for the XPCI image from a distribution of randomly-oriented ellipsoidal pores, and show that we can use this expression to extract quantitative information about the size distribution from single images. We discuss three approaches to evaluating this expression, corresponding to different assumptions about the nature of the size distribution, and validate our results with simulated XPCI images and experimental data from Berea sandstone.

5.
Zhonghua Gan Zang Bing Za Zhi ; 26(7): 535-539, 2018 Jul 20.
Artigo em Chinês | MEDLINE | ID: mdl-30317778

RESUMO

Objective: The effect of total flavonoids of litchi (TFL) on nuclear translocation of nuclear factor-kappa B (NF- kappa B) in rat hepatic stellate cell line (HSC-T6) induced by transforming growth factor - beta 1 (TGF- beta 1) in vitro was studied to explore the mechanism of action of anti-hepatic fibrosis drugs. Methods: HSC-T6 was cultured in vitro, induced by TGFß1 for 24 h, and then treated with TFL at 125, 250 and 500 µg/ml for 48 h. The effect of TFL on NF-κB nuclear translocation in HSC-T6 was observed by confocal laser microscopy. The effects of TFL on the expression of TLR4, p-IκB ɑ, p-NF-κB p65, NF-κB and Collagen I protein were detected by western blot. The expressions of TLR4 and p-NF-κB p65 were detected by immunofluorescence. Data were presented as mean±SEM. Homogeneity test of variance was performed and then followed by one-way analysis of variance (ANOVA). The multiple comparisons between groups were performed by LSD test. P < 0.05 was considered statistically significant. Results: Confocal laser scanning microscopy showed TFL inhibited the nuclear translocation of NF-κB in activated HSC-T6 in a concentration-dependent manner and TFL down regulated the protein expression levels of TLR4, p-IκB ɑ, p-NF-κB p65, NF-κB and collagen I protein in HSC-T6 in a concentration-dependent manner. Conclusion: The mechanism of TFL against hepatic fibrosis may be related to the inhibition of nuclear translocation of NF-κb in the activated HSC-T6 and the expression of TLR4, P-iκbɑ, P-nf-κb p65, NF-κb and collagen I protein in HSC-T6.


Assuntos
Flavonoides , Células Estreladas do Fígado , Litchi , NF-kappa B , Animais , Células de Kupffer , Ratos
6.
Aliment Pharmacol Ther ; 48(2): 160-168, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29856472

RESUMO

BACKGROUND: Tong-Xie-Yao-Fang (TXYF) is a Chinese herbal formula for treating chronic diarrhoea accompanied by abdominal pain. The results were inconsistent in previous trials examining its effect. AIM: To study the efficacy of TXYF granules for treating diarrhoea-predominant irritable bowel syndrome (IBS-D). METHODS: We performed a double-blind, placebo-controlled randomised trial and enrolled 160 participants with IBS-D. The participants had VAS scores ≥3 cm in IBS-D global symptoms and ≥2 days in a week with abdominal pain and loose stools (Bristol score 5, 6 or 7). They were randomly assigned to received TXYF or placebo during a treatment period of 4 weeks, and they were followed up for 8 weeks after treatment. The primary outcome was adequate relief of IBS-D global symptoms for at least 2 of 4 weeks during weeks 1-4. Secondary outcomes included mean weekly VAS scores of IBS-D major symptoms, mean weekly stool frequency, mean weekly Bristol score, and adverse events. RESULTS: 155 of 160 patients completed the trial. We found a significantly higher rate of adequate relief of global symptoms in TXFY group during weeks 1 to 4 (57.5% vs 37.5%, χ2 = 5.6391, P = 0.017); logistic regression analysis showed a similar result (OR 2.2, 95% CI 1.2-4.4, P = 0.016). Most of the secondary outcomes showed superiority of TXYF over placebo in weekly assessment from week 3 to week 7. The adverse event rate was low in both groups (3.8% vs 3.8%, P = 1.000). CONCLUSION: During a 4 week trial, TXFY granules were superior to placebo in controlling symptoms of IBS-D.


Assuntos
Diarreia/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Síndrome do Intestino Irritável/tratamento farmacológico , Dor Abdominal/tratamento farmacológico , Dor Abdominal/etiologia , Administração Oral , Adulto , Diarreia/etiologia , Formas de Dosagem , Método Duplo-Cego , Feminino , Humanos , Síndrome do Intestino Irritável/complicações , Masculino , Pessoa de Meia-Idade , Placebos , Resultado do Tratamento , Adulto Jovem
7.
Cryo Letters ; 38(4): 339-346, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29734436

RESUMO

BACKGROUND: The Rana dybowskii distribute in northeast region of China which have seasonally cold climates. During winter they survival freezing by biosynthesizing carbohydrate cryoprotectants such as high concentrations glucose into blood and all tissues. The essential role of glucose transporter 4 is a high-affinity glucose transporter, which can increase glucose uptake in cells when it stimulated by insulin. OBJECTIVE: In this study, we analysis the full-length GLUT4 mRNA detect the gene levels of GLUT4 in R. dybowskii main tissues by qPCR during low temperature. RESULTS: We found in heart, fat body, skeletal muscle and skin four tissues all express GLUT4, and the levels of GLUT4 decreased on initial cold exposure stage, 8~12 hours, followed 24 hours it recovered. CONCLUSION: This study we firstly indentified and characterized GLUT4 in amphibious, and provide a novel insight into the role of GLUT4 in cryoprotectant synthesis and cell protection in cold hardiness amphibians.


Assuntos
Clonagem Molecular/métodos , Temperatura Baixa , Regulação da Expressão Gênica , Transportador de Glucose Tipo 4/genética , Ranidae/genética , Sequência de Aminoácidos , Animais , China , Criopreservação , Evolução Molecular , Perfilação da Expressão Gênica , Glucose/metabolismo , Transportador de Glucose Tipo 4/química , Transportador de Glucose Tipo 4/metabolismo , Masculino , Músculo Esquelético/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Homologia de Sequência de Aminoácidos
8.
J Econ Entomol ; 108(6): 2789-99, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26470376

RESUMO

The spatiotemporal distribution of source areas for the early immigration of the white-backed planthopper, Sogatella furcifera (Horvάth), at Xiushan in the middle reach of Yangtze River of China, was analyzed with HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) and ArcGIS 10.0. The analysis was based on light trap data collected during April-July in 2000-2012. The synoptic meteorology backgrounds during the immigration periods were analyzed by GrADS (Grid Analysis and Display System). The light trap catches of S. furcifera varied monthly and annually. S. furcifera started immigration in Xiushan in early April to early May, whereas the main immigration period was in July. The distribution of the source areas varied monthly, and the core was moved from the south to the north gradually. The main source areas of S. furcifera in May were in southwestern Guangxi and northern Vietnam. The source areas of S. furcifera in June were located in southwestern Guangxi and western Hunan. Additionally, some of the pests were from southeastern Yunnan. The source areas in July were in northwestern Guangxi, southwestern Guizhou, eastern Yunnan, and the transitional parts of Guangxi, Guizhou, and Yunnan. The sum frequencies of southwest and south winds on the 850 hPa isobaric surface of Xiushan of May-July in heavy occurrence years were more than the light occurrence years. The key meteorological factors were suggested to be vertical perturbation, precipitation, and wind shear during S. furcifera immigration periods.


Assuntos
Distribuição Animal , Hemípteros , Modelos Teóricos , Animais , China , Sistemas de Informação Geográfica , Rios , Tempo (Meteorologia)
9.
Genet Mol Res ; 14(2): 6808-18, 2015 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-26125888

RESUMO

Sugarcane smut, caused by the fungus Sporisorium scitamineum, is one of the main diseases that affect sugarcane worldwide. In the present study, the cDNA-SRAP technique was used to identify genes that are likely to be involved in the response of sugarcane to S. scitamineum infection. In total, 21 bands with significant differential expression during cDNA-SRAP analysis were cloned and sequenced. Real-time qPCR confirmation demonstrated that expression of 19 of these 21 differential bands was consistent with the expression observed during cDNA-SRAP analysis, with a deduced false positive rate of 9.5%. Sequence alignment indicated that 18 of 19 differentially expressed genes showed homologies from 19% to 100% to certain genes in GenBank, including the following genes: topoisomerase (EU048780), ethylene insensitive (EU048778), and tetraspanin (EU048770). A real-time qPCR assay showed that during 0-72 h after pathogen infection, expression of the topoisomerase and the ethylene insensitive genes was upregulated, whereas expression of the tetraspanin gene was downregulated, identical to the expression patterns observed under salicylic acid treatment. Therefore, all three genes are thought to play a role during S. scitamineum challenge, but with different functions. To our knowledge, this is the first report on the application of cDNA-SRAP in differential gene expression analysis of sugarcane during a sugarcane-S. scitamineum interaction. The results obtained also contribute to a better understanding of the molecular mechanisms associated with sugarcane-S. scitamineum interactions.


Assuntos
Regulação da Expressão Gênica de Plantas , Doenças das Plantas/genética , Proteínas de Plantas/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Saccharum/genética , Ustilaginales/crescimento & desenvolvimento , Sequência de Bases , Clonagem Molecular , DNA Topoisomerases/genética , DNA Topoisomerases/imunologia , DNA Topoisomerases/metabolismo , DNA Complementar/genética , DNA Complementar/metabolismo , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno , Dados de Sequência Molecular , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Imunidade Vegetal/genética , Proteínas de Plantas/imunologia , Proteínas de Plantas/metabolismo , Saccharum/imunologia , Saccharum/metabolismo , Saccharum/microbiologia , Alinhamento de Sequência , Análise de Sequência de DNA , Transdução de Sinais , Estresse Fisiológico , Tetraspaninas/genética , Tetraspaninas/imunologia , Tetraspaninas/metabolismo , Ustilaginales/patogenicidade
10.
Genet Mol Res ; 14(3): 7894-909, 2015 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-26214470

RESUMO

Sugarcane smut caused by the fungus Sporisorium scitamineum is a worldwide disease and also one of the most prevalent diseases in sugarcane production in mainland China. To study molecular variation in S. scitamineum, 23 S. scitamineum isolates from the 6 primary sugar-cane production areas in mainland, China (Guangxi, Yunnan, Guangdong, Hainan, Fujian, and Jiangxi Provinces), were assessed using internal transcribed spacer (ITS) methods. The results of ITS sequence analysis showed that the organisms can be defined at the genus level, including Ustilago and Sporisorium, and can also differentiate between closely related species. This method was not suitable for phylogenetic relationship analysis of different S. scitamineum isolates and could not provide support regarding their race ascription at the molecular level. The results of the present study will be useful for studies examining the molecular diversity of S. scitamineum and for establishing a genetic foundation for their pathogenicity differentiation and new race detection. In addition, our results can provide useful information for the pathogen selection principle in sugarcane smut resistance breeding and variety distribution.


Assuntos
Basidiomycota/genética , DNA Espaçador Ribossômico/genética , Variação Genética , Composição de Bases/genética , Sequência de Bases , Basidiomycota/isolamento & purificação , China , Análise por Conglomerados , Dados de Sequência Molecular , Mutação/genética , Filogenia , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase , Saccharum/microbiologia , Alinhamento de Sequência
11.
AJNR Am J Neuroradiol ; 35(11): 2099-105, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24994832

RESUMO

BACKGROUND AND PURPOSE: To date, MRS study of both normal and pathologic brains have focused mainly on the supratentorial regions; few studies have investigated the infratentorial regions. However, the pons, an important structure of the brain, is associated with many neurodegenerative diseases and is often damaged by brain trauma. For MRS study of pontine disease, one must obtain MRS reference data on normal metabolite levels in the pons, including data on how these levels vary with age. The aim of this study was to analyze normal, age-related, metabolic changes in the pons by using turbo spectroscopic imaging. MATERIALS AND METHODS: Seventy-eight healthy subjects with ages ranging from 5 days to 78 years were included in this study. NAA/Cr, Cho/Cr, and Cho/NAA ratios were measured by using turbo spectroscopic imaging. The 78 cases were divided into 4 groups by age: 0-5, 6-20, 21-50, and older than 50 years. The metabolite levels were compared with observed age-related changes among the groups. RESULTS: The normal mean pontine metabolite ratios obtained for the combined age groups were NAA/Cr, 2.44 ± 0.45 (mean); Cho/Cr, 1.93 ± 0.25; and Cho/NAA, 0.83 ± 0.28. Statistically significant differences were found in the NAA/Cr between the 0- to 5- and 6- to 20-year-old groups, and among the 6- to 20-, 21- to 50-, and older than 50-year-old groups. A statistically significant difference was found in Cho/Cr between the 0- to 5- and 6- to 20-year-old subjects; however, no differences were found among the 6- to 20-, 21- to 50-, and older than 50-year-old groups. Statistically significant differences in Cho/NAA were also found among the 4 age groups. The NAA/Cr at birth was low, it rose rapidly at 0-5 years, reaching a peak at approximately 10-20 years, and then gradually decreased. The Cho/Cr decreased rapidly at 0-5 years, then continued to decline, and was stable after 20 years of age. CONCLUSIONS: Turbo spectroscopic imaging is a good method for analyzing normal changes in the pons metabolites during growth, maturation, and aging.


Assuntos
Envelhecimento/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Ponte/metabolismo , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Oncogene ; 33(48): 5546-58, 2014 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24292672

RESUMO

Human protein arginine N-methyltransferase 2 (PRMT2, HRMT1L1) is a protein that belongs to the arginine methyltransferase family, and it has diverse roles in transcriptional regulation through different mechanisms depending on its binding partners. In this study, we provide evidences for the negative effect of PRMT2 on breast cancer cell proliferation in vitro and in vivo. Morever, cyclin D1, one of the key modulators of cell cycle, was found to be downregulated by PRMT2, and PRMT2 was further shown to suppress the estrogen receptor α-binding affinity to the activator protein-1 (AP-1) site in cyclin D1 promoter through indirect binding with AP-1 site, resulting in the inhibition of cyclin D1 promoter activity in MCF-7 cells. Furthermore, a positive correlation between the expression of PRMT2 and cyclin D1 was confirmed in the breast cancer tissues by using tissue microarray assay. In addition, PRMT2 was found to show a high absent percentage in breast caner cell nuclei and the nuclear loss ratio of PRMT2 was demonstrated to positively correlate with cyclin D1 expression and the increasing tumor grade of invasive ductal carcinoma. Those results offer an essential insight into the effect of PRMT2 on breast carcinogenesis, and PRMT2 nuclear loss might be an important biological marker for the diagnosis of breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Ciclina D1/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Adulto , Idoso , Animais , Biomarcadores Tumorais/análise , Western Blotting , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Xenoenxertos , Humanos , Imuno-Histoquímica , Camundongos , MicroRNAs , Pessoa de Meia-Idade , Mutagênese Sítio-Dirigida , Gradação de Tumores , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Análise Serial de Tecidos , Transfecção
13.
Nanotechnology ; 23(33): 335701, 2012 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-22842646

RESUMO

Control of the plasmon-driven chemical reaction for the transformation of 4-nitrobenzenethiol to p,p'-dimercaptoazobenzene by Ag nanoparticle arrays was studied. The Ag nanoparticle arrays were fabricated by means of nanosphere lithography. By changing the PS particle size, the localized surface plasmon resonance (LSPR) peaks of the Ag nanoparticle arrays can be tailored from 460 to 560 nm. The controlled reaction process was monitored by in situ surface-enhanced Raman scattering. The reaction can be dramatically influenced by varying the duration of laser exposure, Ag nanoparticle size, laser power and laser excitation wavelength. The maximum reaction speed was achieved when the LSPR wavelength of the Ag nanoparticle arrays matched the laser excitation wavelength. The experimental results reveal that the strong LSPR can effectively drive the transfer of the 'hot' electrons that decay from the plasmon to the reactants. The experimental results were confirmed by theoretical calculations.


Assuntos
Nanopartículas Metálicas/química , Prata/química , Análise Espectral Raman/métodos , Adsorção , Tamanho da Partícula , Compostos de Sulfidrila/síntese química , Compostos de Sulfidrila/química , Ressonância de Plasmônio de Superfície
14.
J Nanosci Nanotechnol ; 10(10): 6424-7, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21137741

RESUMO

Recently, there is much interest in nanocomposites consisting of metal nanoparticles dispersed in dielectric matrix. Silver is the first candidate used in antibacterial research. In the present study, sliver-containing silica glass is prepared by ion implantation. The bactericidal properties of Ag-implanted samples are investigated using E. coli. The implanted samples are characterized by optical absorption spectroscopy, atomic force microscopy and transmission electron microscopy. The size and position of the silver nanoparticles formed by ion implantation can be optimized by adjusting the implanted process parameters. All the implanted samples show antibacterial properties. But the samples with silver nanoparticle-enriched surfaces possess excellent antibacterial properties in comparison with other implanted samples. This indicates that ion implantation is a potential method for synthesizing antibacterial biomaterials.


Assuntos
Antibacterianos/química , Nanopartículas Metálicas/química , Dióxido de Silício/química , Prata/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Vidro/química , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Prata/farmacologia , Espectrofotometria
15.
Nanoscale Res Lett ; 5(9): 1474-1479, 2010 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-20730115

RESUMO

We report a rational synthesis of maghemite (gamma-Fe(2)O(3)) short-nanotubes (SNTs) by a convenient hydrothermal method and subsequent annealing process. The structure, shape, and magnetic properties of the SNTs were investigated. Room-temperature and low-temperature magnetic measurements show that the as-fabricated gamma-Fe(2)O(3) SNTs are ferromagnetic, and its coercivity is nonzero when the temperature above blocking temperature (T(B)). The hysteresis loop was operated to show that the magnetic properties of gamma-Fe(2)O(3) SNTs are strongly influenced by the morphology of the crystal. The unique magnetic behaviors were interpreted by the competition of the demagnetization energy of quasi-one-dimensional nanostructures and the magnetocrystalline anisotropy energy of particles in SNTs.

16.
Horm Metab Res ; 41(11): 799-804, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19672815

RESUMO

Glucagon-like peptide-1 receptor (GLP-1R), glucose-dependent insulinotropic polypeptide receptor (GIPR), and G protein-coupled receptor 40 (GPR40) are members of G protein-coupled receptors (GPCR) family. They are abundantly expressed in islet beta cells, and mediate effects of incretins and fatty acids in beta cells. Glucose and 5-AMP-activated protein kinase (AMPK) are known to be involved in the regulation of beta cell function. Metformin and the potential therapeutic drug for type 2 diabetes, 5-amino-4-imidazolecarboxamide riboside (AICAR), are both known activators of AMPK. Here we studied the effects of glucose, metformin, and AICAR on the expression of GPCR in INS-1 beta cell. INS-1 beta cells were supplemented with different concentrations of glucose, metformin, or AICAR. The expressions of GLP-1R, GIPR, GPR40, and a nuclear transcription factor - peroxisome-proliferator activated receptor alpha (PPARalpha) - were analyzed by real-time RT-PCR and immunoblotting. The time-course of the mRNA degradation of these receptors was also monitored by applying actinomycin D to cells. We demonstrated that the expressions of GLP-1R, GIPR, and PPARalpha were downregulated when INS-1beta cells were treated with glucose, while their expressions were upregulated when treated with metformin or AICAR. Glucose, metformin, or AICAR treatment had no obvious effect on the expression of GPR40. These results indicate that glucose, metformin, and AICAR regulated the expressions of incretin receptors and PPARalpha, but not GPR40 in beta cells. Whether AMPK is a key regulator of these factors mediated receptor regulation remains to be investigated further.


Assuntos
Aminoimidazol Carboxamida/análogos & derivados , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Metformina/farmacologia , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Ribonucleotídeos/farmacologia , Aminoimidazol Carboxamida/farmacologia , Animais , Linhagem Celular Tumoral , Células Secretoras de Insulina/metabolismo , Ratos
17.
Neurology ; 73(3): 186-94, 2009 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-19620606

RESUMO

OBJECTIVE: To explore factors throughout the lifespan that influence cognition in midlife to late life. METHODS: We conducted a retrospective birth cohort study of 2,062 individuals born during 1921-1954 in Beijing, China. In 2003-2005, birth records were abstracted, and participants then 50-82 years old received standardized examinations for health, cognition, and socio-environmental measures. Using cumulative logit models, we assessed adjusted relative effects of prenatal, early life, and adult factors on mid- to late-life cognition. RESULTS: Most prenatal factors were associated with mid- to late-life cognition in the unadjusted models. However, when childhood and adult factors were sequentially added to the models, the impact of prenatal factors showed successive attenuation in effect size, and became insignificant. In contrast, early life factors remained significantly associated with mid- to late-life cognition even after full life-course adjustments. Specifically, those whose fathers had laborer vs professional occupations (odds ratio [OR](Laborer) 1.74; 95% confidence interval [CI]: 1.25-2.42) had poorer cognitive outcomes, while individuals who drank milk daily in childhood (OR 0.65; 95% CI: 0.54-0.80), had more years of education (OR(10-12 years) 0.60; 95% CI: 0.45-0.81; OR(13+ yrs) 0.29; 95% CI: 0.23-0.38), and were taller adults (OR(height > or = SD) 0.65; 95% CI: 0.49-0.86) had better cognition. The high prenatal risk infants had similar patterns with a trend toward a stronger association between cognition and socioenvironmental factors. CONCLUSION: Mid- to late-life cognition is influenced by factors over the entire lifespan with the greatest impact coming from early life exposures. Nutrition, education, social, and family environment in early life may have a long-term impact on cognition in developing countries.


Assuntos
Transtornos Cognitivos/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Animais , Povo Asiático/estatística & dados numéricos , Criança , Pré-Escolar , Estudos de Coortes , Laticínios/estatística & dados numéricos , Escolaridade , Meio Ambiente , Feminino , Indicadores Básicos de Saúde , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Gravidez , Estudos Retrospectivos , Fatores de Risco , Fatores Socioeconômicos
18.
Appl Microbiol Biotechnol ; 83(6): 1183-90, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19543891

RESUMO

Using the 3114/3115 thermal activity monitor (TAM) air isothermal microcalorimeter, ampoule mode, the heat output of Candida albicans growth at 37 degrees C was measured, and the effect of emodin on C. albicans growth was evaluated by microcalorimetry coupled with chemometric methods. The similarities between the heat flow power (HFP)-time curves of C. albicans growth affected by different concentrations of emodin were calculated by similarity analysis (SA). In the correspondence analysis (CA) diagram of eight quantitative parameters taken from the HFP-time curves, it could be deduced that emodin had definite dose-effect relationship as the distance between different concentrations of it increased along with the dosage and the effect. From the principal component analysis (PCA) on eight quantitative parameters, the action of emodin on C. albicans growth could be easily evaluated by analyzing the change of values of the main two parameters, growth rate constant k (2) and maximum power output P(2)(m). The coherent results of SA, CA, and PCA showed that emodin at different concentrations had different effects on C. albicans growth metabolism: A low concentration (0-10 microg ml(-1)) poorly inhibited the growth of C. albicans, and a high concentration (15-35 microg ml(-1)) could notably inhibit growth of this fungus. This work provided a useful idea of the combination of microcalorimetry and chemometric analysis for investigating the effect of drug and other compounds on microbes.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Emodina/farmacologia , Calorimetria/métodos , Candida albicans/crescimento & desenvolvimento , Relação Dose-Resposta a Droga , Inibidores do Crescimento/farmacologia , Estrutura Molecular
19.
J Appl Microbiol ; 107(4): 1072-80, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19426275

RESUMO

AIMS: This study investigated the anti-fungal activity of coptisine on Candida albicans growth. METHODS AND RESULTS: The metabolic power-time curves of Candida albicans growth at 37 degrees C affected by coptisine were measured by microcalorimetry using an LKB-2277 Bioactivity Monitor with stop-flow mode. Then, the diameter of inhibitory zones in the agar layer was observed using agar cup method, and the minimal inhibitory concentration (MIC) of coptisine on Candida albicans growth was determined by serial dilution method. From the principal component analysis on nine quantitative parameters obtained from the power-time curves, we could easily evaluate the anti-fungal activity of coptisine by analysing the change of values of the main two parameters, growth rate constant k and maximum power output in the log phase P(m, log). The results showed that coptisine had strong anti-fungal activity: at a low concentration (45 microg ml(-1)) began to inhibit the growth of Candida albicans and at a high concentration (500 microg ml(-1)) completely inhibited Candida albicans growth. Coptisine gave big inhibitory zones with diameters between 11 and 43 mm within test range, and the MIC of it was 1000 microg ml(-1). CONCLUSIONS: Coptisine had strong anti-fungal activity on Candida albicans growth. The method of microcalorimetry applied for the assay of anti-fungal activity of coptisine was quantitative, sensitive and simple. SIGNIFICANCE AND IMPACT OF THE STUDY: This work will provide useful information for the development of chemical biology policy in the use of anti-microbials in food and drug production.


Assuntos
Antifúngicos/farmacologia , Berberina/análogos & derivados , Candida albicans/efeitos dos fármacos , Berberina/farmacologia , Calorimetria/métodos , Candida albicans/crescimento & desenvolvimento , Cinética , Testes de Sensibilidade Microbiana , Análise de Componente Principal
20.
Phytomedicine ; 15(4): 253-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18337074

RESUMO

The Tibetan herb Potentilla anserina L. has been widely used in China for many thousands of years to treat hepatitis-B. Bioassay-guided fractionation of the ethanol extract of the rhizomes led to the isolation of a triterpenoid saponin (TS) that was determined to be 2alpha,3beta,19alpha-trihydroxyurs-12-en-28-oic acid beta-D-glucopyranosyl ester. Using models of HBV infection, this compound was evaluated for its effect on HBV antigene expression in the 2.2.15 cell line in vitro and anti-hepatitis B virus (HBV) activities in Peking ducklings in vivo. Results showed that it could decrease the expression levels of HBsAg, HBeAg and HBVDNA in the 2.2.15 cell culture and the inhibitory effect was not due to the cytotoxity of the triterpenoid saponin. The antiviral study in vivo on Peking ducklings also demonstrated that this compound inhibits duck hepatitis B virus (DHBV) DNA replication.


Assuntos
Infecções por Hepadnaviridae/tratamento farmacológico , Vírus da Hepatite B do Pato/efeitos dos fármacos , Hepatite Viral Animal/tratamento farmacológico , Fitoterapia , Potentilla/química , Saponinas/farmacologia , Triterpenos/uso terapêutico , Animais , Antivirais/farmacologia , Carcinoma Hepatocelular/virologia , Linhagem Celular Tumoral , Replicação do DNA/efeitos dos fármacos , DNA Viral/efeitos dos fármacos , Patos , Anticorpos Anti-Hepatite/sangue , Antígenos de Hepatite/sangue , Humanos , Neoplasias Hepáticas/virologia , Extratos Vegetais/uso terapêutico , Rizoma/química , Saponinas/isolamento & purificação , Saponinas/uso terapêutico , Triterpenos/isolamento & purificação , Triterpenos/farmacologia
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