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1.
J Med Entomol ; 50(2): 300-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23540117

RESUMO

Culex flavivirus (CxFV) is an insect-specific flavivirus that was first reported in 2007 in Japan. CxFV strains were isolated from Culex tritaeniorhynchus Giles and Culex pipiens L. group mosquitoes and genetically characterized in Toyama Prefecture, Japan, from 2004 to 2009, to reveal host specificity, mode of transmission, and seasonal and geographical distribution. The minimum infection rate (MIR) of CxFV within Cx. tritaeniorhynchus populations was 0.3 and much lower than that within Cx. pipiens group (17.9). The complete genome sequences of 11 CxFV isolates (four from Cx. tritaeniorhynchus and seven from Cx. pipiens group) consisted of 10,835-10,837 nucleotides. When these 11 isolates and five reference strains (NIID-21-2 and Tokyo strains from Japan, Iowa07 and HOU24518 strains from the United States, H0901 strain from China) were compared, there were 95.2-99.2% nucleotide and 98.1-99.8% amino acid identities. Phylogenetic analysis showed that the 11 isolates were divided into four clusters. One cluster consisted of five isolates from Cx. pipiens group and Cx. tritaeniorhynchus from one site and their nucleotide sequences almost completely matched. One cluster consisted of an isolate with a unique sequence from a Cx. pipiens group mosquito captured in an aircraft from Taiwan, suggesting that it was introduced from abroad. CxFV strains were divided into several groups according to countries when nucleotide sequences of CxFV available in GenBank and 11 Toyama isolates were compared. These results suggest that CxFV is maintained in nature among Culex mosquitoes in a mosquito habitat-specific but not a species-specific manner.


Assuntos
Culex/virologia , Flavivirus/genética , Genoma Viral , Animais , Flavivirus/classificação , Flavivirus/isolamento & purificação , Japão , Dados de Sequência Molecular , Filogenia , RNA Viral/química , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de Proteína , Análise de Sequência de RNA
2.
Dis Esophagus ; 24(7): 523-30, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21453382

RESUMO

In spite of the undisputed importance of altered expression patterns of microRNAs (miRNAs) in various cancers, there is little information on the clinicopathologic significance of cancer-related miRNAs (MIR21, MIR143, MIR144, MIR145, and MIR205) in esophageal squamous cell carcinoma (ESCC). We examined the expression levels of the precursor and mature miRNA genes in ESCC using real-time polymerase chain reaction (PCR). We also investigated the mRNA expression levels of processing elements (RNASEN, DGCR8, and DICER1) that participate in miRNA-biogenesis pathway. Furthermore, we analyzed the relationships between the expression levels of these five miRNAs and the clinicopathologic parameters of ESCC patients. The expression levels of mature MIR21 and mature MIR145 were higher in ESCC than those in normal epithelium (P < 0.05). The mature/pre ratio of MIR21 in ESCC was higher than that in normal epithelium (P < 0.05). With regard to miRNA-processing elements, the expression level of RNASEN was higher in ESCC than in normal epithelium (P < 0.05). Furthermore, altered expression of these miRNAs was related to the clinicopathologic features of ESCC patients. The high expression of mature MIR21 and mature MIR205 was associated with lymph node positivity in ESCC patients (P < 0.05). The high levels of expression of mature MIR143 and mature MIR145 were associated with recurrence of metastasis in ESCC patients (P < 0.05). The findings may imply that miRNA biogenesis is aberrantly accelerated in ESCC. Analysis of the expression levels of miRNAs should provide useful information for evaluation of the staging, prognosis, and treatment of ESCC patients.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
Dev Cell ; 1(6): 749-58, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11740937

RESUMO

Astrocyte differentiation, which occurs late in brain development, is largely dependent on the activation of a transcription factor, STAT3. We show that astrocytes, as judged by glial fibrillary acidic protein (GFAP) expression, never emerge from neuroepithelial cells on embryonic day (E) 11.5 even when STAT3 is activated, in contrast to E14.5 neuroepithelial cells. A CpG dinucleotide within a STAT3 binding element in the GFAP promoter is highly methylated in E11.5 neuroepithelial cells, but is demethylated in cells responsive to the STAT3 activation signal to express GFAP. This CpG methylation leads to inaccessibility of STAT3 to the binding element. We suggest that methylation of a cell type-specific gene promoter is a pivotal event in regulating lineage specification in the developing brain.


Assuntos
Astrócitos/fisiologia , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , Proteína Glial Fibrilar Ácida/genética , Interleucina-6 , Neurônios/fisiologia , Telencéfalo/embriologia , Transativadores/metabolismo , Animais , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Diferenciação Celular/fisiologia , Células Cultivadas , Ilhas de CpG/genética , Proteínas de Ligação a DNA/genética , Células Epiteliais , Feto/fisiologia , Proteína Glial Fibrilar Ácida/metabolismo , Inibidores do Crescimento/farmacologia , Humanos , Fator Inibidor de Leucemia , Linfocinas/farmacologia , Camundongos , Microscopia de Fluorescência , Neurônios/efeitos dos fármacos , Regiões Promotoras Genéticas , Ratos , Fator de Transcrição STAT3 , Transdução de Sinais/fisiologia , Telencéfalo/citologia , Telencéfalo/metabolismo , Transativadores/genética , Transcrição Gênica
4.
J Microsc ; 235(3): 259-72, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19754721

RESUMO

Correlative microscopy is a collection of procedures that rely upon two or more imaging modalities to examine the same specimen. The imaging modalities employed should each provide unique information and the combined correlative data should be more information rich than that obtained by any of the imaging methods alone. Currently the most common form of correlative microscopy combines fluorescence and electron microscopy. While much of the correlative microscopy in the literature is derived from studies of model cell culture systems we have focused, primarily, on correlative microscopy in tissue samples. The use of tissue, particularly human tissue, may add constraints not encountered in cell culture systems. Ultrathin cryosections, typically used for immunoelectron microscopy, have served as the substrate for correlative fluorescence and electron microscopic immunolocalization in our studies. In this work, we have employed the bifunctional reporter FluoroNanogold. This labeling reagent contains both a fluorochrome and a gold-cluster compound and can be imaged by sequential fluorescence and electron microscopy. This approach permits the examination of exactly the same sub-cellular structures in both fluorescence and electron microscopy with a high level of spatial resolution.


Assuntos
Microscopia de Fluorescência/métodos , Microscopia Imunoeletrônica/métodos , Coloração e Rotulagem/métodos , Vilosidades Coriônicas/química , Vilosidades Coriônicas/ultraestrutura , Fluorescência , Ouro , Humanos , Processamento de Imagem Assistida por Computador/métodos , Nanopartículas , Neutrófilos/química , Neutrófilos/ultraestrutura
5.
J Appl Microbiol ; 106(4): 1252-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19187148

RESUMO

AIMS: To develop a convenient and rapid detection method for toxigenic Clostridium botulinum types A and B using a loop-mediated isothermal amplification (LAMP) method. METHODS AND RESULTS: The LAMP primer sets for the type A or B botulinum neurotoxin gene, BoNT/A or BoNT/B, were designed. To determine the specificity of the LAMP assay, a total of 14 C. botulinum strains and 17 other Clostridium strains were tested. The assays for the BoNT/A or BoNT/B gene detected only type A or B C. botulinum strains, respectively, but not other types of C. botulinum or strains of other Clostridium species. Using purified chromosomal DNA, the sensitivity of LAMP for the BoNT/A or BoNT/B gene was 1 pg or 10 pg of DNA per assay, respectively. The assay times needed to detect 1 ng of DNA were only 23 and 22 min for types A and B, respectively. In food samples, the detection limit per reaction was one cell for type A and 10 cells for type B. CONCLUSIONS: The LAMP is a sensitive, specific and rapid detection method for C. botulinum types A and B. SIGNIFICANCE AND IMPACT OF THE STUDY: The LAMP assay would be useful for detection of C. botulinum in environmental samples.


Assuntos
Clostridium botulinum/genética , DNA Bacteriano/análise , Sequência de Bases , Clostridium botulinum/isolamento & purificação , Primers do DNA/genética , DNA Bacteriano/genética , Microbiologia de Alimentos , Dados de Sequência Molecular , Técnicas de Amplificação de Ácido Nucleico/métodos , Plasmídeos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e Especificidade
6.
Placenta ; 29(2): 135-43, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18222537

RESUMO

Proteomics is an area of study that sets as its ultimate goal the global analysis of all of the proteins expressed in a biological system of interest. However, technical limitations currently hamper proteome-wide analyses of complex systems. In a more practical sense, a desired outcome of proteomics research is the translation of large protein data sets into formats that provide meaningful information regarding clinical conditions (e.g., biomarkers to serve as diagnostic and/or prognostic indicators of disease). Herein, we discuss placental proteomics by describing existing studies, pointing out their strengths and weaknesses. In so doing, we strive to inform investigators interested in this area of research about the current gap between hyperbolic promises and realities. Additionally, we discuss the utility of proteomics in discovery-based research, particularly as regards the capacity to unearth novel insights into placental biology. Importantly, when considering under studied systems such as the human placenta and diseases associated with abnormalities in placental function, proteomics can serve as a robust 'shortcut' to obtaining information unlikely to be garnered using traditional approaches.


Assuntos
Placenta/metabolismo , Proteômica , Células Cultivadas , Humanos , Fisiologia Comparada , Proteômica/tendências
7.
Placenta ; 28(2-3): 170-4, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-16600368

RESUMO

In the third trimester, human placental endothelial cells express Fc gamma receptor IIb (FcgammaRIIb). This expression is unique because FcgammaRIIb is generally expressed on immune cells and is typically undetectable in adult endothelial cells. Recently, we found a novel FcgammaRIIb-defined, IgG-containing organelle in placental endothelial cells; this organelle may be a key structure for the transcytosis of IgG across the endothelial layer. In this study, we verify the expression of FcgammaRIIb in endothelial placenta cells and use reverse transcriptase-polymerase chain reaction (RT-PCR) and sequencing analyses to define the expressed FCGR2B mRNA transcript variant. We also investigated the distribution of FCGR2B mRNA and protein within the vascular tree of the full-term human placenta by RT-PCR and quantitative microscopy. The mRNA sequence of FCGR2B expressed specifically in placental endothelial cells is that of transcript variant 2. FcgammaRIIb expression and synthesis occur throughout the placental vascular tree but do not extend into the umbilical cord. This study provides additional information on FcgammaRIIb expression in the human placenta.


Assuntos
Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Placenta/metabolismo , Gravidez/metabolismo , Receptores de IgG/metabolismo , Feminino , Expressão Gênica , Humanos , Microscopia de Fluorescência , Placenta/irrigação sanguínea , Terceiro Trimestre da Gravidez/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de RNA
8.
Biomed Pharmacother ; 60(1): 43-50, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16260113

RESUMO

Tumour cell destruction in boron neutron-capture therapy (BNCT) is due to the nuclear reaction between (10)B and thermal neutrons. It is necessary for effective BNCT therapy to accumulate (10)B atoms in the tumour cells. The delivery system consisted of polyethylene-glycol (PEG) binding liposomes (DPPC/cholesterol/DSPC-PEG2000) with an entrapped (10)B-compound and we evaluated the cytotoxic effects of intravenously injected (10)B-PEG-liposomes on human pancreatic carcinoma xenografts in nude mice with thermal neutron irradiation. After thermal neutron irradiation of mice injected with (10)B-PEG-liposomes, growth of AsPC-1 tumours was suppressed relative to controls. Injection of (10)B-PEG-liposomes caused the greatest tumour suppression with thermal neutron irradiation in vivo. These results suggest that intravenous injection of (10)B-PEG-liposomes can increase the retention of (10)B atoms by tumour cells, causing suppression of tumour growth in vivo, after thermal neutron irradiation.


Assuntos
Boroidretos/administração & dosagem , Terapia por Captura de Nêutron de Boro , Boro/administração & dosagem , Neoplasias Pancreáticas/radioterapia , Compostos de Sulfidrila/administração & dosagem , Animais , Linhagem Celular Tumoral , Humanos , Isótopos , Lipossomos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Modelos Animais , Transplante de Neoplasias , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Polietilenoglicóis/química
9.
Cancer Res ; 54(17): 4595-7, 1994 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-8062248

RESUMO

Seventy-six gastric carcinomas were analyzed with regard to whether or how microsatellite instability was associated with the development of the carcinoma. Microsatellite instability occurred as a late genetic alteration, with an incidence significantly higher in the advanced stage (17 of 51) than in the early stage (3 of 25; P < 0.05). Chromosomal losses on 5q and 17p, detected by polymerase chain reaction-restriction fragment length polymorphism, more frequently accompanied microsatellite instability (9 of 15 and 8 of 11, respectively), compared with carcinomas which lacked instability (5 of 28 and 9 of 30, respectively; P < 0.01 and P < 0.05, respectively). Epstein-Barr virus was observed in only 8 of 76 carcinomas, none of which was associated with microsatellite instability. No significant correlation was found between instability and the familial tendency to develop gastric carcinomas. Our results suggest that microsatellite instability might play a role in the progression of gastric carcinomas but not in Epstein-Barr virus-associated gastric carcinomas.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 17 , Cromossomos Humanos Par 5 , Replicação do DNA , DNA Satélite/genética , Neoplasias Gástricas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Feminino , Herpesvirus Humano 4/genética , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia
10.
Biochim Biophys Acta ; 1235(1): 69-78, 1995 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-7536473

RESUMO

In human neutrophils, alkaline phosphatase (AlkPase), a low-affinity receptor for IgG (FcRIIIB), and complement decay accelerating factor (DAF) are glycosyl-phosphatidylinositol (GPI)-anchored proteins. Varying greatly in biological function these three integral membrane proteins exhibit regulated cell surface expression in neutrophils. Defined by their common membrane-linkage motif, AlkPase, FcRIIIB, and DAF can be released from the lipid bilayer by the action of phosphatidylinositol-specific phospholipase C and are relatively resistant to low temperature extraction with Triton X-100 (TX-100). In this study we show that neutrophil AlkPase, FcRIII, and DAF display differential extractibility; they are relatively insensitive to TX-100 solubilization at 4 degrees C, but are readily extracted with TX-100 at 37 degrees C or by the detergent octyl glucoside at 4 degrees C. The differential extractibility of these GPI-anchored proteins is the same in unstimulated cells, where these proteins exist primarily in an intracellular pool, and stimulated cells, where they are expressed principally at the cell surface. However, no differential extraction effect is observed with two neutrophil transmembrane proteins, complement receptor 1 (CD35, CR1) and MHC Class I in either stimulated or unstimulated cells.


Assuntos
Fosfatase Alcalina/química , Antígenos CD/química , Glicosilfosfatidilinositóis/química , Glicoproteínas de Membrana/química , Neutrófilos/química , Receptores de IgG/química , Adulto , Antígenos CD55 , Antígenos de Histocompatibilidade Classe I/química , Humanos , Masculino , Ativação de Neutrófilo , Neutrófilos/imunologia , Receptores de Complemento 3b/química , Solubilidade
11.
Biochim Biophys Acta ; 1234(1): 74-80, 1995 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-7880861

RESUMO

Distearoyl-N-(3-carboxypropionoyl poly(ethylene glycol) succinyl)phosphatidylethanolamine (DSPE-PEG-COOH) was newly synthesized and used to prepare novel immunoliposomes carrying monoclonal antibodies at the distal ends of the PEG chains (Type C). Liposomes were prepared from egg phosphatidylcholine (ePC) and cholesterol (CH) (2;1, m/m) containing 6 mol% of DSPE-PEG-COOH, and a monoclonal IgG antibody, 34A, which is highly specific to pulmonary endothelial cells, was conjugated to the carboxyl groups of DSPE-PEG-COOH to give various amounts of antibody molecules per liposome. Other immunoliposomes with PEG coating (Type B) or without PEG coating (an earlier type of immunoliposome, Type A) were prepared for comparison. The average molecular weight of PEG in Type B or C immunoliposomes was 2000. Type B and Type C liposomes without antibodies showed prolonged circulation time and reduced reticulo-endothelial system (RES) uptake owing to the presence of PEG. These three different types of 34A-immunoliposomes with 30-35 antibody molecules per vesicle were injected into mice to test the immunotargetability to the lung. The efficiency of lung binding of 34A-Type B was one-half of that of 34A-Type A, though a large amount of 34A-Type B remained in the blood circulation for a long time, suggesting that the steric hindrance of PEG chains reduced not only the immunospecific antibody-antigen binding, but also the RES uptake. The degree of lung binding of 34A-Type C was about 1.3-fold higher than that of 34A-Type A, indicating that recognition by the antibodies attached to the PEG terminal was not sterically hindered and that the free PEG (i.e., that not carrying antibody) was effective in increasing the blood concentration of immunoliposomes by enabling them to evade RES uptake. The latter phenomenon was confirmed by using nonspecific antibody-Type C immunoliposomes (14-Type C), which showed a high blood level for a long time. Our approach provides a simple means of conjugating antibodies directly to the distal end of PEG which is already bound to the liposome membrane, and should contribute to the development of superior targetable drug delivery vehicles for use in diagnostics and therapy.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Animais , Endotélio/imunologia , Lipossomos/administração & dosagem , Lipossomos/química , Lipossomos/farmacocinética , Pulmão/imunologia , Taxa de Depuração Metabólica , Camundongos , Camundongos Endogâmicos BALB C , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Ratos , Ratos Endogâmicos F344 , Relação Estrutura-Atividade , Distribuição Tecidual
12.
Cell Death Differ ; 5(5): 426-31, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-10200492

RESUMO

Influenza virus-infected cultured cells undergo apoptosis after an increment of Fas (APO-1/CD95) on the cell surface. By flow cytometry, cell surface Fas-ligand was detected in virus-infected cells with a time course similar to that of Fas. Moreover, Fas and Fas-ligand were co-expressed in those cells. The mode of induction, however, appeared to be distinct for the two proteins. Influenza virus infection induced the externalization of phosphatidylserine on the cell surface at the early stage of apoptosis, an event that has been observed in cells undergoing Fas-mediated apoptosis. In fact, apoptosis of the virus-infected cells was inhibited in the presence of an antagonistic anti-Fas-ligand monoclonal antibody. These results suggest that influenza virus infection causes augmented expression of both Fas and Fas-ligand and apoptosis is induced when the infected cells come into contact with each other.


Assuntos
Apoptose/genética , Glicoproteínas de Membrana/genética , Orthomyxoviridae/genética , Receptor fas/genética , Anexina A5/metabolismo , Cromatina/genética , Fragmentação do DNA/genética , Proteína Ligante Fas , Citometria de Fluxo , Expressão Gênica , Células HeLa , Humanos , Fosfatidilserinas/metabolismo , Poli I-C/farmacologia , RNA de Cadeia Dupla/farmacologia
13.
J Mol Biol ; 223(1): 373-5, 1992 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-1731082

RESUMO

Proteinase A from Aspergillus niger var. macrosporus is a non-pepsin-type acid proteinase distinctly different in various properties from the family of pepsin-type aspartic proteinases, and so far it remains unknown which residues participate in the catalysis of the enzyme and how the mechanism operates. The acid proteinase A was crystallized from an ammonium sulfate solution by the hanging-drop vapor diffusion method. The space group of the crystals was P2(1)2(1)2(1) with unit cell dimensions of a = 54.7 A, b = 70.4 A and c = 38.0 A. On the assumption that there is one enzyme molecule in the asymmetric unit, the calculated ratio of volume to unit protein mass (Vm) was 1.64 A3 per dalton. Diffraction data were collected up to a resolution higher than 1.5 A, using the Weissenberg camera for macromolecular crystallography with synchrotron radiation. The crystal of proteinase A is, therefore, suitable for the structural analysis with a high resolution.


Assuntos
Ácido Aspártico Endopeptidases/química , Aspergillus/enzimologia , Cristalografia , Conformação Proteica , Difração de Raios X
14.
Toxicol Sci ; 86(1): 61-7, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15843508

RESUMO

Sulfonamide analogues of para-aminobenzoic acid (PABA), a precursor of folate synthesis, have beneficial effects as antifolate, but thyroid peroxidase inhibition has been reported as a side effect that results in promotion of rat thyroid carcinogenesis. In the present study, effects of PABA itself on F344 rat thyroid carcinogenesis after initiation with N-bis(2-hydroxypropyl)nitrosamine (DHPN) were evaluated. In experiment 1, rats in groups 1-4 received a single subcutaneous injection of DHPN at 2800 mg/kg, and groups 5 and 6 received vehicle saline alone. From 1 week after DHPN initiation, rats in groups 2, 3, 4, and 6 were fed basal diet containing 0.25%, 0.5%, 1.0%, and 1.0% PABA, respectively, for 40 weeks. Rats in groups 1 and 5 received basal diet alone throughout the experiment. The final incidence of thyroid follicular cell adenomas and adenocarcinomas was significantly (p < 0.05 or 0.01) increased in groups 3 and 4 as compared to group 1. No thyroid tumors were found in groups 5 and 6. In experiment 2, animals in group 1 were fed basal diet alone, while groups 2 and 3 were given 0.5% and 1.0% PABA in the diet, respectively, for 2 weeks. Thyroid weights in group 3, and serum thyroid stimulating hormone level and proliferative activity of follicular cells in groups 2 and 3 were significantly (p < 0.05 or 0.01) elevated. In addition, the serum thyroxine level in group 3 was significantly (p < 0.05) depressed. These results clearly indicate that PABA exerts promotion/progression effects on rat thyroid carcinogenesis as a result of hypothyroidism followed by negative-feedback via the thyroid-pituitary axis.


Assuntos
Ácido 4-Aminobenzoico/toxicidade , Carcinógenos/toxicidade , Nitrosaminas/toxicidade , Neoplasias da Glândula Tireoide/induzido quimicamente , Animais , Peso Corporal/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344 , Hormônios Tireóideos/sangue , Neoplasias da Glândula Tireoide/sangue , Neoplasias da Glândula Tireoide/patologia
15.
Diabetes Care ; 23(9): 1401-6, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10977041

RESUMO

OBJECTIVE: Serum triglyceride levels are important in the development of atherosclerosis. Although triglyceride levels are generally increased in the postprandial periods, the association between postprandial triglyceride (pTG) levels and atherosclerosis has not been investigated in diabetic patients. To investigate the role of pTG levels in atherosclerosis, we examined the correlation between pTG levels and carotid intimal-medial thickness (IMT). RESEARCH DESIGN AND METHODS: Carotid IMT was measured by ultrasonography in 61 patients with type 2 diabetes. Plasma glucose (PG), insulin, total cholesterol, triglycerides, and HDL cholesterol levels were measured after overnight fasting and 4 h after a meal. RESULTS: Carotid IMT of the patients with fasting hypertriglyceridemia was greater than that of the patients with normal fasting triglyceride (fTG) levels (0.85+/-0.12 vs. 0.76+/-0.14 mm; P = 0.02). The carotid IMT was increased in the patients with pTG levels >2.27 mmol/l. The normo-normo (NN) and normo-hyper (NH) groups consisted of patients with normal fTG levels but with pTG levels <2.27 and >2.27 mmol/l, respectively. Patients with both hypertriglyceridemia and pTG levels >2.27 mmol/l formed the hyper-hyper (HH) group. Carotid IMT was significantly increased in the NH (0.86+/-0.13 mm) and HH (0.85+/-0.12 mm) groups compared with the NN group (0.73+/-0.13 mm; P<0.01). Although postprandial PG, pTG, and fasting LDL cholesterol levels were all independently correlated with carotid IMT, pTG levels had the strongest statistical influence (P = 0.002). CONCLUSIONS: Postprandial hypertriglyceridemia despite normal fTG levels may be an independent risk factor for early atherosclerosis in type 2 diabetes.


Assuntos
Artérias Carótidas/patologia , Diabetes Mellitus Tipo 2/fisiopatologia , Hipertrigliceridemia/fisiopatologia , Adulto , Idoso , Arteriosclerose/epidemiologia , Pressão Sanguínea , Artérias Carótidas/diagnóstico por imagem , Estenose das Carótidas/epidemiologia , LDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Jejum , Feminino , Humanos , Hipertrigliceridemia/complicações , Hipertrigliceridemia/patologia , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial , Valores de Referência , Fatores de Risco , Triglicerídeos/sangue , Túnica Íntima/diagnóstico por imagem , Túnica Íntima/patologia , Túnica Média/diagnóstico por imagem , Túnica Média/patologia , Ultrassonografia
16.
Cardiovasc Res ; 35(3): 514-21, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9415296

RESUMO

OBJECTIVES: Recombinant viral vectors based on the nonpathogenic parvovirus, adeno-associated virus (AAV), have a number of attractive features for gene therapy, including the ability to transduce non-dividing cells and its long-term transgene expression. In this study, an AAV vector containing bacterial beta-galactosidase gene (lacZ) was used to transduce cultured rat vascular smooth muscle cells (VSMC) in vitro and rat thoracic aortas ex vivo. METHODS: VSMC were transduced with AAV-lacZ at multiplicities of infection (MOI) ranging from 5.0 x 10(5) to 1.0 x 10(7). Expression of beta-galactosidase (beta-gal) in VSMC was evaluated by X-gal staining and a beta-gal ELISA method. Excised rat aortas were incubated with medium containing AAV-lacZ. Expression of beta-gal in the aortic segments was evaluated by X-gal staining. RESULTS: With increasing MOI, up to 50% of cultured VSMC were positive by X-gal staining and the beta-gal expression increased up to 15 ng/mg protein. The expression gradually decreased during the culture but was detectable for at least 1 month. In the ex vivo study, AAV vectors transduced endothelial and adventitial cells in rat aortic segments, while no expression was seen in medial VSMC. CONCLUSIONS: AAV vectors can efficiently transduce rat VSMC in vitro. AAV-mediated ex vivo gene transfer into the normal aorta resulted in efficient gene transfer into endothelial and adventitial cells but not into medial VSMC. These findings suggest that AAV-based vectors are promising for use in cardiovascular gene therapy.


Assuntos
Dependovirus , Técnicas de Transferência de Genes , Vetores Genéticos , Óperon Lac , Músculo Liso Vascular/citologia , Aorta Torácica/citologia , Células Cultivadas , Endotélio Vascular/citologia , Expressão Gênica , Humanos
17.
Int J Dev Biol ; 42(2): 141-8, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9551859

RESUMO

To examine the presence and distribution of Six family gene products in a variety of tissues at various developmental stages and in various cell types, we prepared specific antibodies against recombinant Six gene products. The distribution of Six2 and Six4 was examined by immunostaining in the developing mouse embryo. Production of Six2 was detected at E8.5 mainly in the mesenchyme, while Six4 was present in nuclei of neuronal cells in the peripheral region of the mantle layer of developing brain and spinal cord and in various ganglia at E10.5 and E11.5. Specific DNA binding activities of the Six proteins were analyzed by gel retardation super-shift assays using nuclear extracts from different rat tissues and cell lines. Six5 was the dominant isoform observed in the adult kidney, liver and lung but not in the brain. Six4 was not detected in all tested adult tissues, however, it was present in embryonic (FD21) lung nuclear extracts. In contrast, Six4 was detected in a variety of cultured cell lines, including HeLa, 3T3, MDCK and C2C12. Our results suggest that Six4 plays a specific role in the differentiation or maturation of neuronal cells, while Six5 is an adult type Six gene isoform product and is distributed in the kidney, liver and lung.


Assuntos
Embrião de Mamíferos/metabolismo , Genes Homeobox , Proteínas de Homeodomínio/metabolismo , Família Multigênica , Proteínas do Tecido Nervoso/metabolismo , Transativadores , Células 3T3 , Animais , Anticorpos Monoclonais , Linhagem Celular , Núcleo Celular/química , Núcleo Celular/metabolismo , Desenvolvimento Embrionário e Fetal , Células HeLa , Proteínas de Homeodomínio/imunologia , Humanos , Imuno-Histoquímica , Hibridização In Situ , Camundongos , Proteínas do Tecido Nervoso/imunologia , RNA Mensageiro/análise , Ratos , Distribuição Tecidual
18.
J Clin Neurosci ; 22(8): 1361-3, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25913748

RESUMO

We report a 48-year-old Japanese woman with phenylketonuria (PKU) who presented with severe neurological symptoms more than 30 years after discontinuation of dietary treatment. She was diagnosed with PKU at 6-years-old and was treated with a phenylalanine restricted diet until she was 15 years old. When she was 48-years-old she started having difficulty walking. After several months, she presented with severe disturbance of consciousness and was admitted. She was diagnosed as having neurological complications associated with PKU. We observed temporal changes in her laboratory data, brain MRI and single-photon emission computed tomography (SPECT) scan findings. Brain MRI on T2-weighted, fluid-attenuated inversion recovery and diffusion-weighted images revealed high intensity lesions in her bilateral frontal lobes and 123I-IMP SPECT showed marked and diffuse hypoperfusion in the bilateral cerebrum and cerebellum. After the resumption of dietary treatment, serum phenylalanine concentrations immediately decreased to the normal range. However, her neurological symptoms took longer to improve. We also found no clear temporal association between MRI findings and clinical severity. SPECT abnormalities showed marked improvement after treatment. It is well known that PKU patients who discontinue the dietary restriction from their childhood develop minor neurological impairments. However, PKU patients with late-onset severe neurological symptoms are very rare. To our knowledge, this is the first report regarding SPECT findings of PKU patients with late-onset severe neurological deterioration.


Assuntos
Encéfalo/patologia , Fenilcetonúrias/complicações , Fenilcetonúrias/patologia , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Fenilcetonúrias/dietoterapia , Tomografia Computadorizada de Emissão de Fóton Único
19.
Hypertension ; 30(5): 1035-40, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9369252

RESUMO

Our previous in vivo studies (Hou et al. J Clin Invest. 1995;96:2469-2477.) demonstrated that chronic inhibition of nitric oxide synthase led to an exaggerated response to relatively low doses of angiotensin II, resulting in a rapid and marked cardiac fibrosis. To examine further the importance of angiotensin II in inducing cardiac fibrosis and the possibility that nitric oxide serves as a modulator of the proliferative effects of angiotensin II, we used cultured rat cardiac fibroblasts to study the interrelationships between these substances. Angiotensin II induced a delayed DNA synthetic response in quiescent cells that occurred 30 hours after exposure to the hormone. The most pronounced effect of angiotensin II on thymidine uptake occurred 36 to 42 hours after the addition to cells. This response was inhibited in a dose-dependent manner by the addition of either S-nitroso-N-acetylpenicillamine or sodium nitroprusside, each a source of nitric oxide. The nitric oxide donor was most effective in reducing thymidine incorporation when added 12 hours after angiotensin II, whereas the metabolite N-acetylpenicillamine had no effect at any time. The inhibitory effect of S-nitroso-N-acetylpenicillamine was mimicked by 8-bromoguanosine 3':5'-cyclic monophosphate but not by 8-bromoadenosine 3':5'-cyclic monophosphate. Nitric oxide donors did not appear to inhibit the induction of c-fos, Egr-1, or other immediate-early genes in response to angiotensin II. The results suggest that nitric oxide affects the cell cycle following the transition into G, and modulates the proliferation of fibroblasts during cardiac fibrosis induced by angiotensin II.


Assuntos
Angiotensina II/farmacologia , Replicação do DNA/efeitos dos fármacos , Replicação do DNA/fisiologia , Proteínas Imediatamente Precoces , Miocárdio/metabolismo , Óxido Nítrico/farmacologia , Animais , Animais Recém-Nascidos , Células Cultivadas , GMP Cíclico/análogos & derivados , GMP Cíclico/farmacologia , Proteínas de Ligação a DNA/genética , Proteína 1 de Resposta de Crescimento Precoce , Inibidores Enzimáticos/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Miocárdio/citologia , Nitroprussiato/farmacologia , Penicilamina/análogos & derivados , Penicilamina/farmacologia , Proteínas Proto-Oncogênicas c-fos/genética , RNA Mensageiro/metabolismo , Ratos , S-Nitroso-N-Acetilpenicilamina , Timidina/antagonistas & inibidores , Timidina/metabolismo , Fatores de Transcrição/genética
20.
Hypertension ; 23(1 Suppl): I215-9, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8282362

RESUMO

The effects of long-term monotherapy with felodipine, a calcium antagonist, on blood pressure, glucose tolerance, and serum lipid profiles were prospectively investigated in 51 hypertensive patients: 13 with normal glucose tolerance and 38 with glucose intolerance. The levels of plasma glucose, serum lipids, and glycosylated hemoglobin A1c were determined before and during long-term (7.5 +/- 0.5 months; range, 6 to 9 months) therapy with felodipine. A 75-g oral glucose tolerance test was performed before and during long-term felodipine therapy. Significant decreases in both systolic and diastolic blood pressures in both patient groups were maintained during the therapy. Neither fasting nor post-glucose load venous plasma glucose levels were altered in either group of patients, and no patients with normal glucose tolerance developed diabetes mellitus during the study. Serum lipid levels did not change significantly in either group of patients except for significant decreases in high-density lipoprotein cholesterol and apolipoprotein A-I in the group with normal glucose tolerance tests, but those changes remained within the normal range. Furthermore, neither serum lipid nor apolipoprotein levels were altered, even in patients with hypercholesterolemia (total cholesterol levels, > 5.69 mmol/L = 220 mg/dL). These results suggest that long-term therapy with felodipine may not alter glucose and lipid metabolism in hypertensive patients, and felodipine appears to be useful as an antihypertensive agent for hypertensive patients with either dyslipidemia or impaired glucose metabolism.


Assuntos
Apolipoproteínas/metabolismo , Glicemia/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Colesterol/sangue , Felodipino/uso terapêutico , Hipertensão/sangue , Hipertensão/tratamento farmacológico , Triglicerídeos/sangue , Análise de Variância , Apolipoproteína A-I/metabolismo , Apolipoproteínas B/metabolismo , Glicemia/efeitos dos fármacos , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Diástole/efeitos dos fármacos , Feminino , Intolerância à Glucose/sangue , Teste de Tolerância a Glucose , Hemoglobinas Glicadas/metabolismo , Humanos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pulso Arterial/efeitos dos fármacos , Sístole/efeitos dos fármacos
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