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1.
J Med Virol ; 83(4): 568-73, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21328369

RESUMO

The 2009 pandemic H1N1 influenza A virus spread quickly worldwide in 2009. Since most of the fatal cases were reported in developing countries, rapid and accurate diagnosis methods that are usable in poorly equipped laboratories are necessary. In this study, a mobile detection system for the 2009 H1N1 influenza A virus was developed using a reverse-transcriptase loop-mediated isothermal amplification (RT-LAMP) kit with a disposable pocket-warmer as a heating device (designated as pwRT-LAMP). The pwRT-LAMP can detect as few as 100 copies of the virus--which is nearly as sensitive as real-time reverse-transcription polymerase chain reaction (RT-PCR)--and does not cross-react with RNA of seasonal influenza viruses. To evaluate the usefulness of the pwRT-LAMP system, nasal swab samples were collected from 56 patients with flu-like symptoms and were tested. Real-time RT-PCR confirmed that the 2009 H1N1 influenza A virus was present in 27 of the 56 samples. Of these 27 positive samples, QuickVue Influenza A+B immunochromatography detected the virus in only 11 samples (11/27; 40.7%), whereas the pwRT-LAMP system detected the virus in 26 of the 56 samples (26/27 of the positive samples; 96.3%). These findings indicate that the mobile pwRT-LAMP system is an accurate diagnostic system for the 2009 H1N1 influenza A virus, and has great potential utility in diagnosing future influenza pandemics.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/diagnóstico , Influenza Humana/virologia , Técnicas de Amplificação de Ácido Nucleico/métodos , Sistemas Automatizados de Assistência Junto ao Leito , Virologia/métodos , Adulto , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
2.
Connect Tissue Res ; 51(3): 197-207, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20053131

RESUMO

This study examined the effect of extracellular matrix (ECM) on the osteogenic differentiation capacity and osteogenesis of dental follicle cells. Single cell-derived porcine dental follicle cells (DFC-I) obtained at the early stage of crown formation in tooth were subcultured and characterized using periodontal ligament cells (PDLC) and bone marrow-derived mesenchymal stem cells (BMSC) as comparison cell populations. The effect of ECM constituents including collagen type I, fibronectin, laminin, and collagen type IV on the differentiation of DFC-1 into osteogenic-lineage cells was evaluated in vitro. In addition, the DFC-1, PDLC, and BMSC populations were compared for osteogenic capacity in vitro by Alizarin red staining and in vivo by transplantation. DFC-I showed different features from PDLC and BMSC. Different components of ECM had different effects on the differentiation of DFC-1 into osteogenic-lineage cells in vitro. Alkaline phosphatase activity and matrix mineralization as early- and late-stage markers of osteogenesis, respectively, supported the differentiation of DFC-1 into osteogenic-related cells in vitro. All three cell types showed equivalent osteogenic capacity in vivo at 4 weeks postoperatively. There were no statistically significant differences among the cell populations with respect to capacity for bone formation. These results suggest a potential application for dental follicle cells in bone-tissue engineering.


Assuntos
Saco Dentário/citologia , Matriz Extracelular/fisiologia , Células-Tronco Mesenquimais/citologia , Osteogênese/fisiologia , Animais , Células da Medula Óssea/citologia , Diferenciação Celular , Linhagem da Célula , Células Cultivadas , Saco Dentário/efeitos dos fármacos , Proteínas da Matriz Extracelular/farmacologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Ligamento Periodontal/citologia , Células-Tronco , Suínos , Engenharia Tecidual
3.
Biochem Biophys Res Commun ; 382(2): 353-8, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19281797

RESUMO

Current standard techniques for bone tissue engineering utilize ex vivo expanded osteogenic cells. However, ex vivo expansion requires serum, which may hinder clinical applications. Here, we report the feasibility and efficacy of bone tissue engineering with human bone marrow stromal cells (BMSCs) expanded in serum-free conditions. Bone marrow was aspirated from 4 healthy donors and adherent cells were cultured in either serum-free medium (STEMPRO((R)) MSC SFM) or conventional serum-containing medium (alpha-MEM supplemented with 10% serum). Efficacy of expansion was greater in serum-free medium. Phenotypically, serum-free expanded BMSCs were smaller in cell-size and showed expression of CD105(++) and CD146(dim). After osteogenic induction, serum-free expanded BMSCs showed lower alkaline phosphatase activity. However, they showed higher responsiveness to induction. In vivo bone-forming ability was also confirmed. In conclusion, bone tissue engineering with serum-free expanded BMSCs is feasible and as efficient as that obtained with BMSCs expanded in conventional serum-containing medium.


Assuntos
Células da Medula Óssea/fisiologia , Osso e Ossos/fisiologia , Osteogênese , Engenharia Tecidual/métodos , Antígenos CD/análise , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Osso e Ossos/citologia , Técnicas de Cultura de Células , Tamanho Celular , Meios de Cultura Livres de Soro/farmacologia , Endoglina , Humanos , Receptores de Superfície Celular/análise , Células Estromais/citologia , Células Estromais/efeitos dos fármacos , Células Estromais/fisiologia , Molécula 1 de Adesão de Célula Vascular/análise
4.
J Nanosci Nanotechnol ; 8(11): 6153-7, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19198357

RESUMO

A novel approach for selective diameter control of single-walled carbon nanotubes (SWNTs) is performed in the gas-phase growth using two kinds of carbon sources with different decomposition properties; the one carbon source (1st carbon source) is the organic solvent which is difficult to decompose in the reactor and the another carbon source (2nd carbon source) is facile to decompose. The diameter distributions of SWNTs synthesized with various conditions of the flow rate of the 2nd carbon source were investigated by resonant Raman scattering, optical absorption, and photoluminescence (PL) mapping measurements. It was found that increasing the flow rate of the ethylene tends to decrease the diameter of synthesized SWNTs, probably due to the earlier nucleation of SWNTs induced by the ethylene addition. The controlling the flow rate of the ethylene used as a 2nd carbon source can selectively tune the diameter distribution of SWNTs in our growth system.


Assuntos
Cristalização/métodos , Nanotecnologia/métodos , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Titânio/química , Gases/química , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Transição de Fase , Propriedades de Superfície
5.
J Phys Chem B ; 110(12): 5849-53, 2006 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-16553390

RESUMO

Reversed micelles containing metallic ions have been used as precursors of novel catalysts for the gas-phase synthesis of single-walled carbon nanotubes (SWNTs). This technique possesses the following advantages: (i) excellent solubility in organic solvents, which are used as reactants and (ii) facile preparation of multicomponent catalysts enabling systematic screening of catalyst compositions for the synthesis of SWNTs. In this study, we report the results of the screening study on the catalytic behavior of Fe-Mo binary catalysts during the synthesis of SWNTs. The results suggested that the catalytic ability was closely related to the strain of the crystal structure of Fe-Mo catalysts formed in the reaction and/or the phase transition caused by dissolution of the Mo atoms. The addition of lithium to the Fe-Mo binary catalysts has revealed an increase in the yield of SWNTs.

6.
J Phys Chem B ; 110(35): 17420-4, 2006 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-16942079

RESUMO

A simple and efficient technique is described for measuring photoluminescence (PL) maps of carbon nanotubes (NTs) in the extended IR range (1-2.3 mum). It consists of preparing an NT/surfactant/gelatin film and measuring PL spectra using a combination of a tunable Ti-sapphire laser excitation and FTIR detection. This procedure has been applied to a wide range of single- and double-wall NTs unveiling chirality and diameter distributions that have so far been very difficult to measure. The problems associated with deducing these distributions are discussed by comparing absorption and PL mapping data for NT samples prepared under different conditions.

7.
J Phys Chem B ; 109(7): 2632-7, 2005 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-16851268

RESUMO

We have studied the compatibility of various catalysts for ethylene and ethanol chemical vapor deposition (CVD) syntheses of single-walled carbon nanotubes (SWNTs) on Si substrates. A strong selectivity between the catalyst elemental species and carbon source was found; SWNT yield for Fe (Co) catalysts was much higher for ethylene (ethanol) CVD than for ethanol (ethylene) CVD. This strong and completely opposite selectivity implies significantly different SWNT growth mechanisms for ethanol and ethylene CVD on Si substrates.

8.
J Phys Chem B ; 109(21): 10647-52, 2005 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-16852292

RESUMO

Nanoparticle catalysts are essential and indispensable for all syntheses of single-walled carbon nanotubes (SWCNTs). We have prepared size-controlled Co, Co-Mo, and Fe-Mo nanoparticles by the reversed micelle method as the catalysts for the gas-phase pyrolytic synthesis of SWCNTs. From the investigation of the relation between the sizes of the nanoparticles and the alkyl-chain lengths of the cationic surfactants, dialkyldimethylammonium bromides, it has been found that the alkyl groups of the surfactants could play a role in controlling the sizes of the nanoparticles and that the alkyl chain of the surfactant should be preferably less than 10 carbon atoms at most to prepare smaller-size nanoparticles with a narrow size distribution. The reduction of the particle size increases the number of nanoparticles in the colloidal solution and leads to a higher yield of SWCNTs.

9.
Chem Commun (Camb) ; (23): 2806-7, 2002 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-12478756

RESUMO

Crystalline boron nanowires with tetragonal structure have been synthesized based on laser ablation of a B/NiCo target; the nanowires are sometimes single crystals and have a droplet at one end of the nanowire; the droplet contains B, Ni and Co elements, which indicates that the vapor-liquid-solid (VLS) mechanism may play a key role in the growth of the boron nanowires.

10.
Gan To Kagaku Ryoho ; 30(11): 1836-8, 2003 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-14619533

RESUMO

We report a 73-year-old female who had been operated on for sigmoid colon cancer and neck lymph node metastases. Tumor size was controlled by systemic chemotherapy for about 3 years. During the chemotherapy, toxicity over grade 2 was not observed and good QOL was maintained on an outpatient basis. It is suggested that low-dose systemic chemotherapy may be useful for patients with poor general status.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Camptotecina/análogos & derivados , Linfonodos/patologia , Neoplasias do Colo Sigmoide/tratamento farmacológico , Neoplasias do Colo Sigmoide/patologia , Idoso , Camptotecina/administração & dosagem , Colo Sigmoide/cirurgia , Terapia Combinada , Combinação de Medicamentos , Feminino , Fluoruracila/administração & dosagem , Humanos , Irinotecano , Leucovorina/administração & dosagem , Metástase Linfática , Pescoço , Neoplasias do Colo Sigmoide/cirurgia , Sobreviventes , Tegafur/administração & dosagem , Uracila/administração & dosagem
11.
Gan To Kagaku Ryoho ; 31(11): 1685-8, 2004 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-15553683

RESUMO

This case was a 69-year-old male who had advanced gastric cancer with unresectable multiple liver metastases (Stage IV). He received a combination therapy consisting of a continuous venous infusion (cisplatin: CDDP 10 mg/body, 5-FU 500 mg/body, day 1-28). As a result, metastatic tumors in the liver completely disappeared and a total gastrectomy was sequentially performed. Four years after the surgery, neck lymph node (LN) metastases and the right adrenal metastasis appeared, and chemotherapy (TS-1, and sequentially TS-1+CDDP) was performed. But, the chemotherapy to eradicate the metastases was hardly enough to be effective. Next, docetaxel (DOC 60 mg/m2 q3w) was started. After 9 courses, they were effective and marked regressions (70%). A total of 15 courses of docetaxel administration were possible until tumor progression recurred. This regimen was not severe in toxicity for the duration except for grade 3 poor appetite. Docetaxel will be a key drug for the gastric cancer. In case of responding well to the chemotherapy, we can hope for an extended long-term survival with a continuation of this regimen.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/uso terapêutico , Fluoruracila/uso terapêutico , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/terapia , Taxoides/administração & dosagem , Idoso , Cisplatino/administração & dosagem , Docetaxel , Combinação de Medicamentos , Gastrectomia , Hepatectomia , Humanos , Infusões Intravenosas , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Masculino , Ácido Oxônico/administração & dosagem , Piridinas/administração & dosagem , Tegafur/administração & dosagem
12.
Gan To Kagaku Ryoho ; 30(11): 1669-72, 2003 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-14619490

RESUMO

The prognosis of advanced hepatocellular carcinoma (HCC) is extremely poor. Patient 1 was a 43-year-old male with major portal tumor thrombi. He received combination therapy consisting of continuous arterial infusion (MTX 30 mg/m2, day 1, CDDP/5-FU 6 mg/m2: 250 mg/m2, day 1-14) and subcutaneous injection of IFN-alpha (500 x 10(4) U, 3 times a week, 4 weeks). Patient 2 was a 66-year-old male with major hepatic venous tumor thrombi. He received combination therapy consisting of continuous arterial infusion (5-FU 6 mg/m2: 250 mg/m2, day 1-14) and subcutaneous injection of IFN-alpha (500 x 10(4) U, 3 times a week, 4 weeks). Decrease in tumor was observed in both patients markers and marked regression of tumor was observed in both patients. They are still in complete response. This combination therapy is an effective strategy for advanced HCC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Interferon-alfa/administração & dosagem , Neoplasias Hepáticas/tratamento farmacológico , Adulto , Idoso , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Esquema de Medicação , Fluoruracila/administração & dosagem , Hepatite C/complicações , Humanos , Infusões Intra-Arteriais , Injeções Subcutâneas , Masculino , Metotrexato/administração & dosagem , Prognóstico , Indução de Remissão
13.
Artigo em Inglês | MEDLINE | ID: mdl-21147007

RESUMO

OBJECTIVE: Stem cells isolated from human dental follicles as a potential cell source for bone-tissue engineering were examined for correcting a critical bone defect. STUDY DESIGN: Impacted third molars were collected and single cell-derived cell populations were cultivated in growth medium. Single cell-derived cell lines were examined in terms of cell shape, gene expression patterns, differentiation capacity in vitro, and osteogenic potential in vivo. RESULTS: Three distinct cell populations were identified with different morphologies, patterns of gene expression, and differentiation capacity. All 3 cell populations promoted bone formation when transplanted into surgically created critical-size defects in immunodeficient rat calvaria, compared with control animals without cell transplantation, although one of these populations showed a weak capacity for osteogenetic differentiation in vitro. CONCLUSIONS: Human dental follicle can derive at least 3 unique cell populations in culture, all of which promote bone formation in vivo.


Assuntos
Células-Tronco Adultas/transplante , Regeneração Óssea/fisiologia , Saco Dentário/citologia , Osteogênese/fisiologia , Transplante de Células-Tronco , Adipogenia/fisiologia , Células-Tronco Adultas/classificação , Células-Tronco Adultas/citologia , Animais , Diferenciação Celular , Linhagem Celular , Condrogênese/fisiologia , Células Clonais/classificação , Células Clonais/citologia , Células Clonais/transplante , Humanos , Ratos , Ratos Endogâmicos F344 , Crânio/cirurgia , Transplante Heterólogo
14.
Tissue Eng Part A ; 16(2): 663-73, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19754223

RESUMO

Although human bone marrow stromal cells (BMSCs) have the ability to form bone when transplanted, the responsible factors for in vivo osteogenic abilities are poorly understood. Here we report conditions that are required for human BMSCs to demonstrate their in vivo osteogenic abilities. BMSCs were obtained from healthy donors and their in vivo osteogenic abilities were analyzed. Transplantation analyses revealed that the passage number and length of osteogenic induction significantly affected ectopic bone formation. Although 2-week induction increased the percentage of success in bone formation compared with the 1-week induction, BMSCs completely lost their in vivo osteogenic ability after passage 4 regardless of the length of osteogenic induction. Despite their in vivo osteogenic ability, no significant difference was observed in alkaline phosphatase activity or gene expression of osteogenic markers between BMSCs at passages 1 and 3. Differences were only observed in in vitro mineralizing abilities. Application of basic fibroblast growth factor helped to maintain the BMSCs in vivo osteogenic ability; basic fibroblast growth factor altered cell growth and expression of HLA-DR. The results strongly suggest that there are several required conditions for human BMSCs to demonstrate their bone-forming capabilities, which should be further investigated and considered when designing a protocol for clinical bone tissue engineering.


Assuntos
Células da Medula Óssea/citologia , Técnicas de Cultura de Células/métodos , Osteogênese/fisiologia , Adulto , Fosfatase Alcalina/metabolismo , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/enzimologia , Contagem de Células , Proliferação de Células/efeitos dos fármacos , Feminino , Fator 2 de Crescimento de Fibroblastos/farmacologia , Humanos , Masculino , Osteogênese/efeitos dos fármacos , Células Estromais/citologia , Células Estromais/efeitos dos fármacos , Células Estromais/enzimologia , Células Estromais/transplante , Fatores de Tempo
15.
Endocrinology ; 150(4): 1662-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19095745

RESUMO

Serum aldosterone level is clinically known to correlate with body weight and insulin resistance. Because the underlying molecular mechanism is largely unknown, we examined the effect of aldosterone on insulin-induced metabolic signaling leading to glucose uptake in 3T3-L1 adipocytes. Aldosterone reduced the amounts of insulin receptor substrate (IRS) 1 and IRS2 in a time- and dose-dependent manner. As a result, insulin-induced phosphorylation of Akt-1 and -2, and subsequent uptake of 2-deoxyglucose were decreased. Degradation of IRSs was effectively prevented by a glucocorticoid receptor antagonist and antioxidant N-acetylcysteine, but not by a mineralocorticoid receptor antagonist. Because aldosterone induced phosphorylation of IRS1 at Ser(307), responsible kinases were investigated, and we revealed that rapamycin and BMS345541, but neither SP600125 nor calphostin C, conferred for degradation of IRSs. Although lactacystin prevented the degradation of IRSs, glucose uptake was not preserved. Importantly, sucrose-gradient-sediment intracellular fraction analysis revealed that lactacystin did not effectively restore the reduction of IRS1 in the low-density microsome fraction, important for the transduction of insulin's metabolic signaling. These results indicate that aldosterone deteriorates metabolic action of insulin by facilitating the degradation of IRS1 and IRS2 via glucocorticoid receptor-mediated production of reactive oxygen species, and activation of IkappaB Kinase beta and target of rapamycin complex 1. Thus, aldosterone appears to be a novel key factor in the development of insulin resistance in visceral obesity.


Assuntos
Aldosterona/farmacologia , Transporte Biológico/efeitos dos fármacos , Proteínas Substratos do Receptor de Insulina/metabolismo , Insulina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Células 3T3-L1 , Acetilcisteína/análogos & derivados , Acetilcisteína/farmacologia , Adenoviridae/genética , Animais , Western Blotting , Inibidores de Cisteína Proteinase/farmacologia , Glucose/metabolismo , Imunoprecipitação , Leupeptinas/farmacologia , Camundongos , Fosforilação/efeitos dos fármacos , Receptor de Insulina/metabolismo , Transdução de Sinais/efeitos dos fármacos
16.
Nano Lett ; 5(12): 2618-23, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16351225

RESUMO

Band gap photoluminescence (PL) is observed from "as-grown" single-walled carbon nanotubes (SWNTs) in solid form. The relative PL intensities for six specific semiconducting SWNTs are compared directly to those of the micelle-encapsulated SWNTs' solutions to investigate the influence of the micelle dispersion process on PL measurements. The results indicate that sodium dodecyl sulfate (SDS) and sodium cholate (SC) selectively solubilize smaller-diameter nanotubes, whereas sodium dodecylbenzene sulfonate (SDBS) solution does not exhibit significant diameter selectivity within the diameter range studied here (d(t) = 0.829-0.966 nm).


Assuntos
Coloides/química , Cristalização/métodos , Luminescência , Nanotecnologia/métodos , Nanotubos de Carbono/química , Nanotubos de Carbono/efeitos da radiação , Fotoquímica/métodos , Coloides/efeitos da radiação , Luz , Teste de Materiais , Micelas , Nanotubos de Carbono/ultraestrutura , Soluções
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