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1.
Anal Bioanal Chem ; 415(17): 3487-3501, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37219581

RESUMO

Early detection of histamine in foodstuffs/beverages could be useful in preventing various diseases. In this work, we have prepared a free-standing hybrid mat based on manganese cobalt (2-methylimodazole)-metal organic frameworks (Mn-Co(2-MeIm)MOF) and carbon nanofibers (CNFs) and explored as a non-enzymatic electrochemical sensor for determining the freshness of fish and bananas based on histamine estimation. As-developed hybrid mat possesses high porosity with a large specific surface area and excellent hydrophilicity those allow easy access of analyte molecules to the redox-active metal sites of MOF. Furthermore, the multiple functional groups of the MOF matrix can act as active adsorption sites for catalysis. The Mn-Co(2-MeIm)MOF@CNF mat-modified GC electrode demonstrated excellent electrocatalytic activities toward the oxidation of histamine under acidic conditions (pH = 5.0) with a faster electron transfer kinetics and superior fouling resistance. The Co(2-MeIm)MOF@CNF/GCE sensor exhibited a wide linear range from 10 to 1500 µM with a low limit of detection (LOD) of 89.6 nM and a high sensitivity of 107.3 µA mM-1 cm-2. Importantly, as-developed Nb(BTC)MOF@CNF/GCE sensor is enabled to detect histamine in fish and banana samples stored for different periods of time, which thus indicates its practical viability as analytical histamine detector.


Assuntos
Carbono , Nanofibras , Animais , Carbono/química , Cobalto/química , Manganês , Histamina , Nanofibras/química , Eletrodos , Técnicas Eletroquímicas
2.
J Med Genet ; 59(5): 470-480, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-33753533

RESUMO

BACKGROUND: Down-sloping sensorineural hearing loss (SNHL) in people in their teens and 20s hampers efficient learning and communication and in-depth social interactions. Nonetheless, its aetiology remains largely unclear, with the exception of some potential causative genes, none of which stands out especially in people in their teens and 20s. Here, we examined the role and genotype-phenotype correlation of lipoxygenase homology domain 1 (LOXHD1) in down-sloping SNHL through a cohort study. METHODS: Based on the Seoul National University Bundang Hospital (SNUBH) genetic deafness cohort, in which the patients show varying degrees of deafness and different onset ages (n=1055), we have established the 'SNUBH Teenager-Young Adult Down-sloping SNHL' cohort (10-35 years old) (n=47), all of whom underwent exome sequencing. Three-dimensional molecular modelling, minigene splicing assay and short tandem repeat marker genotyping were performed, and medical records were reviewed. RESULTS: LOXHD1 accounted for 33.3% of all genetically diagnosed cases of down-sloping SNHL (n=18) and 12.8% of cases in the whole down-sloping SNHL cohort (n=47) of young adults. We identified a potential common founder allele, as well as an interesting genotype-phenotype correlation. We also showed that transcript 6 is necessary and probably sufficient for normal hearing. CONCLUSIONS: LOXHD1 exceeds other genes in its contribution to down-sloping SNHL in young adults, rising as a signature causative gene, and shows a potential but interesting genotype-phenotype correlation.


Assuntos
Surdez , Perda Auditiva Neurossensorial , Perda Auditiva , Adolescente , Adulto , Proteínas de Transporte/genética , Estudos de Coortes , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/epidemiologia , Perda Auditiva Neurossensorial/genética , Humanos , Lipoxigenase , Adulto Jovem
3.
Am J Nephrol ; 51(7): 556-564, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32610315

RESUMO

BACKGROUND: Polycystic kidney disease (PKD) is a hereditary disease characterized by cyst formation in the kidneys bilaterally. It has been observed that semaphorin-3C (SEMA3C) is overexpressed in polycystic kidney epithelial cells. It is hypothesized that upregulated SEMA3C would contribute to survival of polycystic kidney epithelial cells. Furthermore, as the kidney is a highly vascularized organ, the secreted SEMA3C from PKD epithelial cells will affect glomerular endothelial cells (GECs) in a paracrine manner. METHODS: To evaluate the effect of SEMA3C on renal cells, siSEMA3C-treated PKD epithelial cells were used for further analysis, and GECs were exposed to recombinant SEMA3C (rSEMA3C). Also, co-culture and treatment of conditioned media were employed to confirm whether PKD epithelial cells could influence on GECs via SEMA3C secretion. RESULTS: SEMA3C knockdown reduced proliferation of PKD epithelial cells. In case of GECs, exposure to rSEMA3C decreased angiogenesis, which resulted from suppressed migratory ability not cell proliferation. CONCLUSIONS: This study indicates that SEMA3C is the aggravating factor in PKD. Thus, it is proposed that targeting SEMA3C can be effective to mitigate PKD.


Assuntos
Células Endoteliais/metabolismo , Glomérulos Renais/patologia , Neovascularização Fisiológica , Doenças Renais Policísticas/patologia , Semaforinas/metabolismo , Técnicas de Cultura de Células/métodos , Linhagem Celular , Movimento Celular , Proliferação de Células , Células Cultivadas , Meios de Cultura/metabolismo , Células Endoteliais/patologia , Técnicas de Silenciamento de Genes , Humanos , Glomérulos Renais/irrigação sanguínea , Glomérulos Renais/citologia , Doenças Renais Policísticas/tratamento farmacológico , Proteínas Recombinantes/metabolismo , Semaforinas/antagonistas & inibidores , Semaforinas/genética , Transdução de Sinais , Regulação para Cima
4.
Nurs Health Sci ; 21(3): 375-381, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30957355

RESUMO

In this study, we identified the relationships between illness uncertainty, subjective health, and the use of complementary and alternative medicine in patients undergoing hemodialysis. In total, 138 participants who were diagnosed with stages 4-5 chronic kidney disease and currently receiving hemodialysis were included. A cross-sectional, correlational design was utilized. Illness uncertainty was associated with education, monthly income, employment, and subjective health. The use of complementary and alternative medicine was not related to illness uncertainty. Among the subdomains of illness uncertainty, ambiguity and unpredictability were related to subjective health; 24.6% of the participants were currently using complementary and alternative medicine and 19.6% had used it in the past. Such methods were mainly used for the effective treatment of diseases or relief of symptoms; 88.5% of those using complementary and alternative medicine consumed vitamins, specific foods, or dietary supplements. However, the proportion of participants who consulted with health-care providers was not high. When planning nursing interventions for patients treated with hemodialysis, assessments on illness uncertainty and complementary and alternative medicine use are needed.


Assuntos
Terapias Complementares/psicologia , Diálise Renal/psicologia , Incerteza , Adulto , Idoso , Terapias Complementares/métodos , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Diálise Renal/métodos , Insuficiência Renal Crônica/psicologia , Insuficiência Renal Crônica/terapia , República da Coreia , Inquéritos e Questionários
5.
Cancer Cell Int ; 17: 25, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28289331

RESUMO

BACKGROUND: Cancer stem cells (CSCs), a subpopulation in tumors, are known to cause drug resistance, tumor recurrence and metastasis. Based on the characteristic formation of mammospheres in in vitro conditions, the mammosphere formation assay has become an essential tool for quantifying CSC activity in breast cancer research. However, manual counting of mammospheres is a time-consuming process that is not amenable to high-throughput screening, and there are occasional inaccuracies in the process of determining the mammosphere diameter. In this study, we proposed a novel automated counting method of mammosphere using the National Institute of Standards and Technology (NIST)'s Integrated Colony Enumerator (NICE) with a screening of protein kinase library. METHODS: Human breast cancer cell line MCF-7 was used for evaluation of tumor sphere efficiency, migration, and phenotype transition. Cell viability was assessed using MTT assay, and CSCs were identified by an analysis of CD44 expression and ALDEFLUOR assay using flow cytometry. Automated counting of mammosphere using NICE program was performed with a comparison to the result of manual counting. After identification of inhibitors to ameliorate CSC formation by screening a library of 79 protein kinase inhibitors using automated counting in primary, secondary and tertiary mammosphere assay, the effect of selected kinase inhibitors on migration, colony formation and epithelial-to-mesenchymal transition (EMT) of MCF-7 cells was investigated. RESULTS: Automated counting of mammosphere using NICE program was an easy and less time-consuming process (<1 min for reading 6-well plate) which provided a comparable result with manual counting. Inhibition of calcium/calmodulin-dependent protein kinase II (CaMKII), Janus kinase-3 (JAK-3), and IκB kinase (IKK) were identified to decrease the formation of MCF-7-derived CSCs in primary, secondary and tertiary mammosphere assay. These protein kinase inhibitors alleviated TGF-ß1-induced migration, colony formation and EMT of MCF-7 cells. CONCLUSIONS: We have developed a novel automated cell-based screening method which provided an easy, accurate and reproducible way for mammosphere quantification. This study is the first to show the efficacy of an automated medium-throughput mammosphere-counting method in CSC-related research with an identification of protein kinase inhibitors to ameliorate CSC formation.

6.
Mol Cell Probes ; 30(1): 56-60, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26738688

RESUMO

A multiplex RT-PCR (mRT-PCR) assay to detect H3N2 CIV genomic segments was developed as a rapid and cost-effective method. Its performance was evaluated with forty-six influenza A viruses from different hosts using three primer sets which amplify four segments of H3N2 CIV simultaneously. The mRT-PCR has been successful in detecting the viral segments, indicating that it can improve the speed of diagnosis for H3N2 CIV and its reassortants.


Assuntos
Doenças do Cão/virologia , Vírus da Influenza A Subtipo H3N2/genética , Infecções por Orthomyxoviridae/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Animais , Análise Custo-Benefício , Doenças do Cão/diagnóstico , Cães , Genoma Viral/genética , Humanos , Infecções por Orthomyxoviridae/diagnóstico , Infecções por Orthomyxoviridae/virologia , RNA Viral/genética , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa/economia , Sensibilidade e Especificidade
7.
Virus Genes ; 52(2): 204-17, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26810402

RESUMO

Canine influenza A virus (CIV) causes a respiratory disease among dog populations and is prevalent in North America and Asia. Recently, Asian H3N2 CIV infection has been of particular concern, with recent reports related to reassortants with pandemic 2009 strains, direct transmission from a human H3N2, a possibility of H3N2 CIV transmission to other mammals, and even the first outbreak of H3N2 CIVs in North America in April 2015. However, despite these global concerns, our understanding of how influenza A virus transmission impacts the overall populations of H3N2 CIVs remains incomplete. Hence, we investigated the evolutionary history of the most recent two Korean CIV isolates, A/canine/Korea/BD-1/2013 and A/canine/Korea/DG1/2014, along with 57 worldwide CIVs, using comprehensive molecular analyses based on genomic genotyping. This study presents that the new Korean CIV isolates are closely related to the predominantly circulating H3N2 CIVs with genotypes K, G, E, 3B, F, 2D, F, and 1E, carrying several mutations in antigenic and host determinant sites. Also, our findings show that the genome-wide genetic variations within the H3N2 CIVs are low; however, two antigenic protein (HA and NA) analysis demonstrates genetic diversification of the H3N2 CIVs, which evolves independently between Korea and China.


Assuntos
Doenças do Cão/virologia , Vírus da Influenza A Subtipo H3N2/genética , Tipagem Molecular , Infecções por Orthomyxoviridae/veterinária , Animais , Cães , Evolução Molecular , Variação Genética , Genótipo , Humanos , Vírus da Influenza A Subtipo H3N2/classificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Filogenia , RNA Viral , República da Coreia , Análise de Sequência de DNA
8.
J Biol Chem ; 289(13): 9254-62, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24515114

RESUMO

Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited renal disorder. Although a myriad of research groups have attempted to identify a new therapeutic target for ADPKD, no drug has worked well in clinical trials. Our research group has focused on the receptor for advanced glycation end products (RAGE) gene as a novel target for ADPKD. This gene is involved in inflammation and cell proliferation. We have already confirmed that blocking RAGE function attenuates cyst growth in vitro. Based on this previous investigation, our group examined the effect of RAGE on cyst enlargement in vivo. PC2R mice, a severe ADPKD mouse model that we generated, were utilized. An adenovirus containing anti-RAGE shRNA was injected intravenously into this model. We observed that RAGE gene knockdown resulted in loss of kidney weight and volume. Additionally, the cystic area that originated from different nephron segments decreased in size because of down-regulation of the RAGE gene. Blood urea nitrogen and creatinine values tended to be lower after inhibiting RAGE. Based on these results, we confirmed that the RAGE gene could be an effective target for ADPKD treatment.


Assuntos
Cistos/tratamento farmacológico , Terapia de Alvo Molecular , Rim Policístico Autossômico Dominante/tratamento farmacológico , Receptores Imunológicos/metabolismo , Adenoviridae/genética , Animais , Linhagem Celular , Proliferação de Células , Cistos/genética , Cistos/patologia , Cistos/fisiopatologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Testes de Função Renal , Camundongos , Rim Policístico Autossômico Dominante/genética , Rim Policístico Autossômico Dominante/patologia , Rim Policístico Autossômico Dominante/fisiopatologia , Proteína Quinase D2 , Proteínas Quinases/deficiência , Proteínas Quinases/genética , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/deficiência , Receptores Imunológicos/genética , Transdução de Sinais
9.
J Hum Genet ; 60(8): 455-60, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25994864

RESUMO

Personality is a determinant of behavior and lifestyle that is associated with health and human diseases. Despite the heritability of personality traits is well established, the understanding of the genetic contribution to personality trait variation is extremely limited. To identify genetic variants associated with each of the five dimensions of personality, we performed a genome-wide association (GWA) meta-analysis of three cohorts, followed by comparison of a family cohort. Personality traits were measured with the Revised NEO Personality Inventory for the five-factor model (FFM) of personality. We investigated the top five single-nucleotide polymorphisms (SNPs) for each trait, and revealed the most highly association with neuroticism and TACC2 (rs1010657, P=8.79 × 10(-7)), extraversion and PTPN12 (rs12537271, P=1.47 × 10(-7)), openness and IMPAD1 (rs16921695, P=5 × 10(-8)), agreeableness and RPS29 (rs8015351, P=1.27 × 10(-6)) and conscientiousness and LMO4 (rs912765, P=2.91 × 10(-6)). It had no SNP reached the GWA study threshold (P<5 × 10(-8)). When expanded the SNPs up to top 100, the correlation of PTPRD (rs1029089) and agreeableness was confirmed in Healthy Twin cohort with other 13 SNPs. This GWA meta-analysis on FFM personality traits is meaningful as it was the first on a non-Caucasian population targeted to FFM of personality traits.


Assuntos
Povo Asiático/genética , Estudo de Associação Genômica Ampla/estatística & dados numéricos , Personalidade/genética , Adulto , Idoso , Povo Asiático/etnologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inventário de Personalidade , Polimorfismo de Nucleotídeo Único , República da Coreia/epidemiologia
10.
Virol J ; 12: 64, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25879943

RESUMO

BACKGROUND: Bovine Leukemia virus (BLV) infection of cattle has been reported in Korea for more than three decades. However, to date, there have been few studies regarding Korean BLV since 1980s. Thus, the purpose of this study is to perform a diagnosis and molecular characterization of BLV strains circulating in Korea and to estimate genetic diversity of different genotypes of BLV. METHOD: To investigate the distribution of BLV variants in the world and assess the evolutionary history of Korean BLV isolates, a comprehensive molecular analysis of the BLV env gp51 gene was conducted using recent worldwide BLV isolates. The isolates included 50 samples obtained from two cattle farms in southeastern Korea in 2014. RESULTS: Sequence and phylogenetic analyses of partial 444-nt fragment sequences and complete gp51 sequences of BLV revealed eight distinct genotypes of BLV showing geographic distribution of the world. Most Korean BLV isolates were found to belong to genotype 1 which is a major genotype prevailed throughout the world, and only four isolates from one farm were classified as genotype 3 related to the US and Japan isolates. Analysis of amino acids of Korean BLV isolates showed several sequence substitutions in the leader peptide, conformational epitope, and neutralizing domain regions. The observations suggest the possibility of affecting on viral infectivity and formation. CONCLUSION: Korean BLV isolates showed the close relationship to genotype 1 and 3. Further study to identify the diversity of BLV circulating in Korea is necessary with samples collected nationwide because this study is the first report of BLV genotype 3 being in circulation in Korea.


Assuntos
Leucose Enzoótica Bovina/virologia , Vírus da Leucemia Bovina/classificação , Vírus da Leucemia Bovina/genética , Filogenia , Proteínas do Envelope Viral/genética , Sequência de Aminoácidos , Animais , Bovinos , Leucose Enzoótica Bovina/diagnóstico , Evolução Molecular , Variação Genética , Genótipo , Vírus da Leucemia Bovina/isolamento & purificação , Dados de Sequência Molecular , República da Coreia , Alinhamento de Sequência
11.
J Nanosci Nanotechnol ; 15(1): 665-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26328422

RESUMO

One-pot Si-Si/Si-O dehydrocoupling of hydrosilanes with alcohols (1:1.5 mole ratio), promoted by a mixture of AgNO3-H2PtCl6 (150/1 mole ratio) readily gave poly(alkoxysilane)s in good yield (62-91%). The addition of small amount of platinum complex to form nanoparticles facilitated the silicon polymer formation when compared to the reaction rate with AgNO3 alone. The primary/secondary hydrosilanes [p-X-C6H4SiH3 (X = H, CH3, OCH3, F), PhCH2SiH3, and (PhSiH2)2] and alcohols [MeOH, EtOH, (i)PrOH, PhOH, and CF3(CF2)2CH2OH] were used for the reaction. The weight average molecular weight and polydispersity of the poly(alkoxysilane)s were in the range of 1,690-7,100 Dalton and 1.44-3.49, respectively. The reaction of phenylsilane with ethanol (1:3 mole ratio) using the Ag-Pt complexes produced triethoxyphenylsilane only, as expected. The reaction of phenylsilane with Ge-132 produced an insoluble cross-linked gel.


Assuntos
Técnicas de Química Sintética/métodos , Nanopartículas/química , Platina/química , Silanos/química , Nitrato de Prata/química , Álcoois , Germânio , Peso Molecular , Compostos Organometálicos , Compostos de Platina , Polímeros/química , Propionatos
12.
Biomed Mater ; 19(4)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38688311

RESUMO

This study investigated the effectiveness of bone regeneration upon the application of leptin and osteolectin to a three-dimensional (3D) printed poly(ϵ-caprolactone) (PCL) scaffold. A fused deposition modeling 3D bioprinter was used to fabricate scaffolds with a diameter of 4.5 mm, a height of 0.5 mm, and a pore size of 420-520 nm using PCL (molecular weight: 43 000). After amination of the scaffold surface for leptin and osteolectin adhesion, the experimental groups were divided into the PCL scaffold (control), the aminated PCL (PCL/Amine) scaffold, the leptin-coated PCL (PCL/Leptin) scaffold, and the osteolectin-coated PCL (PCL/Osteo) scaffold. Next, the water-soluble tetrazolium salt-1 (WST-1) assay was used to assess cell viability. All groups exhibited cell viability rates of >100%. Female 7-week-old Sprague-Dawley rats were used forin vivoexperiments. Calvarial defects were introduced on the rats' skulls using a 5.5 mm trephine bur. The rats were divided into the PCL (control), PCL/Leptin, and PCL/Osteo scaffold groups. The scaffolds were then inserted into the calvarial defect areas, and the rats were sacrificed after 8-weeks to analyze the defect area. Micro-CT analysis indicated that the leptin- and osteolectin-coated scaffolds exhibited significantly higher bone regeneration. Histological analysis revealed new bone and blood vessels in the calvarial defect area. These findings indicate that the 3D-printed PCL scaffold allows for patient-customized fabrication as well as the easy application of proteins like leptin and osteolectin. Moreover, leptin and osteolectin did not show cytotoxicity and exhibited higher bone regeneration potential than the existing scaffold.


Assuntos
Regeneração Óssea , Leptina , Poliésteres , Impressão Tridimensional , Ratos Sprague-Dawley , Alicerces Teciduais , Leptina/metabolismo , Animais , Alicerces Teciduais/química , Regeneração Óssea/efeitos dos fármacos , Ratos , Poliésteres/química , Feminino , Engenharia Tecidual/métodos , Sobrevivência Celular/efeitos dos fármacos , Crânio/efeitos dos fármacos , Humanos , Osteogênese/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Teste de Materiais
13.
Proteomics ; 13(1): 134-41, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23212942

RESUMO

Autosomal dominant polycystic kidney disease (ADPKD) is an inheritable and progressive kidney disease featured by the formation of fluid-filled cysts. In a previous study, transgenic mice overexpressing human PKD2 gene were produced as an ADPKD animal model. To select genes controlled by PKD2, 2DE was performed using kidney tissues of 12- and 18-month-old transgenic mice. The protein localization was detected by immunohistochemistry, and 3D culture was utilized to observe in vitro cystogenesis. As a result, N-myc downstream-regulated gene 1 (NDRG1) was chosen as a candidate regulator gene of cystogenesis. NDRG1 is an intracellular protein involved in cellular proliferation and differentiation. This gene was expressed much higher in the kidney of hPKD2 TG mice. Also, the high level of NDRG1 protein was detected in the cyst lining epithelial cells. The hypothesis that PKD2 gene regulates NDRG1 expression was supported, and NDRG1 knockdown resulted in attenuation of cyst growth in vitro. Furthermore, NDRG1 knockdown suppressed cellular growth in mouse inner medullary collecting duct-3 cells. We found that early growth response 1, a transcription factor that binds to the NDRG1 promoter, was mediated in the NDRG1 expression regulation by PKD2. In this study, we found the novel gene that was involved in cystogenesis, which will provide the new insight in ADPKD.


Assuntos
Proteínas de Ciclo Celular , Cistos , Proteína 1 de Resposta de Crescimento Precoce , Peptídeos e Proteínas de Sinalização Intracelular , Canais de Cátion TRPP , Animais , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proliferação de Células , Líquido Cístico/metabolismo , Cistos/genética , Cistos/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Rim/metabolismo , Camundongos , Camundongos Transgênicos , Rim Policístico Autossômico Dominante/genética , Rim Policístico Autossômico Dominante/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Canais de Cátion TRPP/genética , Canais de Cátion TRPP/metabolismo
14.
J Nanosci Nanotechnol ; 13(8): 5645-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23882810

RESUMO

The boric oxide deposition was performed to improve the oxidation resistivity of carbon nanofiber (CNF) from electrospinning at elevated temperatures. The stabilized electrospun polyacrylonitrile (PAN) nanofibers were coated with boric oxide, followed by heat treatment up to 1000, 1200, and 1400 degrees C in an inert nitrogen atmosphere. The relative oxidation resistance of boric oxide-coated CNFs showed oxidation resistive property, which was determined by weight loss after running a thermogravimetric analyzer (TGA) under air flow. The data were used for the calculations of activation energies through Arrhenius plot. The oxidation resistance of the boric oxide-coated CNFs was depended on the heat treatment temperature, the higher the temperature more resistive to oxidation. The boric oxide-coated CNFs showed extended oxidation resistivity as remaining 40-83% (w) of the original weight at the high temperature 1000 degrees C under air.

15.
J Nanosci Nanotechnol ; 13(1): 638-42, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23646789

RESUMO

The generation of silver nanoparticle/bis(o-phenolpropyl)silicone composites have been facilitated by the addition of sodium tetrachloroaurate or gold(Ill) chloride (< 1 wt% of NaAuCl4 or AuCl3) to the reaction of silver nitrate (AgNO3) with bis(o-phenolpropyl)silicone [BPPS, (o-phenolpropyl)2(SiMe2O)n, n = 2,3,8,236]. TEM and FE-SEM data showed that the silver nanoparticles having the size of < 20 nm are well dispersed throughout the BPPS silicone matrix in the composites. XRD patterns are consistent with those for polycrystalline silver. The size of silver nanoparticles augmented with increasing the relative molar concentration of AgNO3 added with respect to BPPS. The addition of gold complexes (1-3 wt%) did not affect the size distribution of silver nanoparticles appreciably. In the absence of BPPS, the macroscopic precipitation of silver by agglomeration, indicating that BPPS is necessary to stabilize the silver nanoparticles surrounded by coordination.


Assuntos
Cristalização/métodos , Ouro/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Silicones/química , Prata/química , Catálise , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
16.
J Nanosci Nanotechnol ; 13(1): 702-5, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23646801

RESUMO

Combinative one-pot Si-Si/Si-O dehydrocoupling of hydrosilanes with alcohols (1:1.5 mole ratio), mediated by a mixture of AgNO3-AuCl3 (100/1 mole ratio) rapidly produced poly(alkoxysilane)s in reasonably high yield. The addition of small amount of gold complex to the reaction mixture effectively accelerated the coupling reaction compared to the reaction rate with AgNO3 alone. The hydrosilanes include p-X-C6H4SiH3 (X = H, CH3, OCH3, F), PhCH2SiH3, and (PhSiH2)2. The alcohols include MeOH, EtOH, iPrOH, PhOH, and CF3(CF2)2CH2OH. The weight average molecular weight and polydispersity of the poly(alkoxysilane)s were in the range of 1,600-8,000 Dalton and 1.4-3.5, respectively. The dehydrocoupling reactions of phenylsilane with ethanol (1:3 mole ratio) in the presence of the Ag-Au complexes gave only triethoxyphenylsilane.


Assuntos
Álcoois/química , Cristalização/métodos , Ouro/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Silanos/química , Prata/química , Catálise , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
17.
Am J Respir Crit Care Med ; 185(11): 1205-17, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22383501

RESUMO

RATIONALE: Chronic obstructive pulmonary disease (COPD) is characterized by chronic inflammation, alveolar destruction, and airway and vascular remodeling. However, the mechanisms that lead to these diverse alterations have not been defined. OBJECTIVES: We hypothesized that IL-18 plays a central role in the pathogenesis of these lesions. METHODS: We generated and characterized lung-specific, inducible IL-18 transgenic mice. MEASUREMENTS AND MAIN RESULTS: Here we demonstrate that the expression of IL-18 in the mature murine lung induces inflammation that is associated with the accumulation of CD4(+), CD8(+), CD19(+), and NK1.1(+) cells; emphysema; mucus metaplasia; airway fibrosis; vascular remodeling; and right ventricle cardiac hypertrophy. We also demonstrate that IL-18 induces type 1, type 2, and type 17 cytokines with IFN-γ-inhibiting macrophage, lymphocyte, and eosinophil accumulation while stimulating alveolar destruction and genes associated with cell cytotoxicity and IL-13 and IL-17A inducing mucus metaplasia, airway fibrosis, and vascular remodeling. We also highlight interactions between these responses with IL-18 inducing IL-13 via an IL-17A-dependent mechanism and the type 1 and type17/type 2 responses counterregulating each another. CONCLUSIONS: These studies define the spectrum of inflammatory, parenchymal, airway, and vascular alterations that are induced by pulmonary IL-18; highlight the similarities between these responses and the lesions in COPD; and define the selective roles that type 1, type 2, and type 17 responses play in the generation of IL-18-induced pathologies.


Assuntos
Citocinas/metabolismo , Interleucina-18/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/patologia , Enfisema Pulmonar/metabolismo , Enfisema Pulmonar/patologia , Resistência das Vias Respiratórias/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Citometria de Fluxo , Immunoblotting , Marcação In Situ das Extremidades Cortadas , Interleucina-13/metabolismo , Interleucina-17/metabolismo , Interleucina-18/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Doença Pulmonar Obstrutiva Crônica/imunologia , Enfisema Pulmonar/imunologia , RNA Mensageiro/análise , Distribuição Aleatória , Estatísticas não Paramétricas
18.
Nurs Health Sci ; 15(1): 65-72, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23094961

RESUMO

The association of asthma symptoms with cigarette smoking and alcohol consumption in Korean adolescents was investigated in this study using the data of Korean Youth Risk Behavior Survey. Associated risk factors for experiencing asthma symptoms were explored in 3432 adolescents. In the symptomatic group, 21.7% were current smokers, compared to 10.9% in the asymptomatic group. Current smokers in the symptomatic group also smoked more cigarettes than those in the asymptomatic group. In the symptomatic group, 27.4% were current drinkers, compared to 17.9% in the asymptomatic group. Current drinkers in the symptomatic group were more likely to drink alcohol and to have experienced severe intoxication than those in the asymptomatic group. Participants who had been diagnosed within one year (odds ratio = 5.19, 95% confidence interval = 4.17-6.44) and those who had smoked over 20 days during the past 30 days (odds ratio = 1.77, 95% confidence interval = 1.26-2.49) were more likely to experience asthma symptoms. Healthcare providers should identify the risk behaviors of adolescents with asthma and counsel them and their parents simultaneously.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Povo Asiático/estatística & dados numéricos , Asma/epidemiologia , Fumar/epidemiologia , Adolescente , Comportamento do Adolescente , Consumo de Bebidas Alcoólicas/efeitos adversos , Asma/etiologia , Causalidade , Criança , Comorbidade , Estudos Transversais , Feminino , Humanos , Masculino , República da Coreia/epidemiologia , Fatores de Risco , Fumar/efeitos adversos , Inquéritos e Questionários
19.
Biochem Biophys Res Commun ; 419(3): 459-65, 2012 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-22342670

RESUMO

Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary renal disease. ADPKD is characterized by cyst development that leads to abnormal kidney structure. Renal tubules are a fundamental unit of architecture, so controls of tubular growth and formation are important for proper kidney function. The molecular mechanisms of tubulogenesis are being actively studied as the basis of diagnosis and treatment of ADPKD. Mxi1 is a member of the MAD family of proteins that functions in terminal differentiation, inhibition of cell cycle progression and tumor suppression, while the Myc protein, which is antagonized by Mxi1, causes renal cystogenesis. Based on these molecular relationships, the present study implicated Mxi1 with ADPKD be demonstrating that curtailed Mxi1 gene expression caused cyst formation in Mxi1-deficient mice. To ascertain whether Mxi1 affects renal epithelial cell tubulogenesis, three-dimensional cultures (3D culture) of mIMCD-3 cells and stably Mxi1 over-expressed mIMCD-3 cells were established. The results indicated that over-expression of the Mxi1 gene plays a role in the regulation of tubulogenesis by regulating some genes participating in renal epithelial branching tubulogenesis such as matrix metalloproteinase 9 (MMP9), integrins, fibronectin, and E-cadherin. The results support the suggestion that over-expression of Mxi1 can suppress renal epithelial tubulogenesis. In particular, MMP9 is greatly affected by the expression level of Mxi1. It can be concluded that mIMCD-3 cells that stably over-express Mxi1 fail to form renal epithelial tubules because of abnormally reduced expression of MMP9.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Células Epiteliais/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Túbulos Renais/crescimento & desenvolvimento , Inibidores de Metaloproteinases de Matriz , Organogênese/genética , Proteínas Supressoras de Tumor/biossíntese , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Técnicas de Cultura de Células , Linhagem Celular , Células Epiteliais/metabolismo , Inativação Gênica , Túbulos Renais/citologia , Túbulos Renais/metabolismo , Metaloproteinase 9 da Matriz/genética , Camundongos , Proteínas Supressoras de Tumor/genética
20.
Xenobiotica ; 42(5): 496-501, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22077103

RESUMO

The hepatic uptake of pitavastatin is mediated by carriers, especially OATP1B1, which is encoded by the SLCO1B1 gene. Because the liver is a target organ of pitavastatin, OATP1B1 is responsible for both the pharmacological effects and clearance of pitavastatin. The effects of the SLCO1B1*15 allele on the pharmacokinetics (PK) of pitavastatin were studied. Pitavastatin 2 mg was orally administered to 38 subjects with SLCO1B1*1a/*1b (n = 20), *1b/*15 (n = 13), or *15/*15 (n = 5). After pitavastatin administration, the plasma concentrations of pitavastatin and pitavastatin lactone were assayed for up to 48 h using liquid chromatography-tandem mass spectrometry. In comparison to the SLCO1B1*1a/*1b subjects, only a C(max) was slightly higher in the SLCO1B1*1b/*15 subjects. However, the SLCO1B1*15/*15 subjects had a 1.74-fold higher AUC(inf) (285.5 ± 14.5 vs. 164.6 ± 41.3 ng·h/mL; p < 0.001), a 2.21-fold higher C(max) (106.7 ± 15.1 vs. 48.3 ± 13.4 ng/mL; p < 0.001), and a 47.3% lower apparent oral clearance (13.1 ± 3.9 vs. 6.9 ± 0.4 L/h; p < 0.001) of pitavastatin. For pitavastatin lactone, there were no significant differences in AUC(inf), C(max), t(1/2), and t(max) among the three genotypes. Unlike previous studies, the disposition of pitavastatin exposure was not altered in subjects with the SLCO1B1*1b/*15 genotype, except C(max). However, pitavastatin exposure was significantly increased in subjects with the SLCO1B1*15/*15 genotype due to reduced hepatic absorption.


Assuntos
Alelos , Transportadores de Ânions Orgânicos/genética , Quinolinas/farmacocinética , Administração Oral , Relação Dose-Resposta a Droga , Humanos , Transportador 1 de Ânion Orgânico Específico do Fígado , Quinolinas/administração & dosagem , Quinolinas/sangue , Fatores de Tempo
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