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1.
Evol Comput ; 28(3): 405-435, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31120772

RESUMO

We introduce an acceleration for covariance matrix adaptation evolution strategies (CMA-ES) by means of adaptive diagonal decoding (dd-CMA). This diagonal acceleration endows the default CMA-ES with the advantages of separable CMA-ES without inheriting its drawbacks. Technically, we introduce a diagonal matrix D that expresses coordinate-wise variances of the sampling distribution in DCD form. The diagonal matrix can learn a rescaling of the problem in the coordinates within a linear number of function evaluations. Diagonal decoding can also exploit separability of the problem, but, crucially, does not compromise the performance on nonseparable problems. The latter is accomplished by modulating the learning rate for the diagonal matrix based on the condition number of the underlying correlation matrix. dd-CMA-ES not only combines the advantages of default and separable CMA-ES, but may achieve overadditive speedup: it improves the performance, and even the scaling, of the better of default and separable CMA-ES on classes of nonseparable test functions that reflect, arguably, a landscape feature commonly observed in practice. The article makes two further secondary contributions: we introduce two different approaches to guarantee positive definiteness of the covariance matrix with active CMA, which is valuable in particular with large population size; we revise the default parameter setting in CMA-ES, proposing accelerated settings in particular for large dimension. All our contributions can be viewed as independent improvements of CMA-ES, yet they are also complementary and can be seamlessly combined. In numerical experiments with dd-CMA-ES up to dimension 5120, we observe remarkable improvements over the original covariance matrix adaptation on functions with coordinate-wise ill-conditioning. The improvement is observed also for large population sizes up to about dimension squared.


Assuntos
Algoritmos , Evolução Biológica , Simulação por Computador , Análise Multivariada , Densidade Demográfica
2.
Pharmazie ; 72(1): 10-16, 2017 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-29441891

RESUMO

Nanomaterials are frequently used in microelectronics, cosmetics, and sunscreens. Platinum reagents are commonly used in disease diagnosis, cosmetics, and the food industry. Although research into the development of nanomaterialbased drug delivery systems has yielded promising results, the toxicity of these materials is not fully understood. We investigated the toxicity and drug interactions of 1- and 8-nm diameter platinum nanoparticles (nPt1 and nPt8, respectively) in mice. Acute hepato-renal toxicity of intravenously administered platinum nanoparticles was evaluated biochemically and histologically. Dose-dependent increases in serum markers of hepato-renal function (serum aminotransferases and blood urea nitrogen) were observed following administration of nPt1, whereas nPt8 had no effect, even at 20 mg/kg. Moreover, nPt1 induced interleukin (IL)-6 and IL-1ß production 3 and 6 hours after administration. The effect of nPts on drug-induced toxicity was evaluated in mice injected intraperitoneally with carbon tetrachloride or cisplatin, with or without intravenous administration of platinum nanoparticles. All treatments in the absence of nanoparticles were non-lethal and resulted in moderate toxicity. However, exacerbated toxicity was observed in mice injected with carbon tetrachloride or cisplatin together with nPt1, but not in mice co-injected with nPt8. We found that nPt1 cause hepato-renal damage, and the effect is enhanced by chemical inducers of hepatotoxicity and nephrotoxicity. This is the first report demonstrating that nPt1 not only are hepatotoxic and nephrotoxic but also exacerbate drug toxicity. These findings will be useful for future nanotechnology and nanoscience research.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/patologia , Nefropatias/induzido quimicamente , Nefropatias/patologia , Nanopartículas Metálicas/toxicidade , Platina/toxicidade , Alanina Transaminase/sangue , Animais , Antineoplásicos/toxicidade , Aspartato Aminotransferases/sangue , Nitrogênio da Ureia Sanguínea , Tetracloreto de Carbono/toxicidade , Cisplatino/toxicidade , Relação Dose-Resposta a Droga , Interações Medicamentosas , Interleucina-1beta/biossíntese , Interleucina-1beta/genética , Interleucina-6/biossíntese , Interleucina-6/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula
3.
Br J Pharmacol ; 173(5): 913-24, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26676684

RESUMO

BACKGROUND AND PURPOSE: This investigation aimed to establish the basis of a pharmacotherapy for nifedipine-induced gingival overgrowth. Gingival overgrowth has been attributed to the enhanced growth of gingival fibroblasts. In this study, we investigated the effects of 18-α-glycyrrhetinic acid (18α-GA) on growth, the cell cycle, and apoptosis and on the regulators of these processes in gingival fibroblasts isolated from patients who presented with nifedipine-induced gingival overgrowth. EXPERIMENTAL APPROACH: Gingival fibroblasts were cultured in medium containing 1% FBS with/without 10 µM 18α-GA for 24 or 48 h, and the cell number, cell cycle phase distribution, relative DNA content, apoptotic cell number and morphological characteristics of the cells undergoing apoptosis were measured together with the levels of proteins that regulate these processes and the level of caspase activity. KEY RESULTS: 18α-GA significantly decreased cell numbers and significantly increased the percentage of cells in the sub-G1 and G0 /G1 phases of the cell cycle and the number of apoptotic cells. Nuclear condensation and fragmentation of cells into small apoptotic bodies appeared in the fibroblasts treated with 18α-GA. In addition, 18α-GA significantly decreased the protein levels of cyclins A and D1, CDKs 2 and 6, phosphorylated Rb (ser(780) and ser(807/811)), Bcl-xL and Bcl-2 and increased the protein levels of p27, cytosolic cytochrome c, pro-caspase-3, and cleaved caspase-3 and the activities of caspases 3 and 9. CONCLUSIONS AND IMPLICATIONS: 18α-GA inhibited gingival fibroblast growth by suppressing the G1 /S phase transition and inducing apoptosis. In conclusion, 18α-GA may be used as a pharmacotherapy for nifedipine-induced gingival overgrowth.


Assuntos
Fibroblastos/efeitos dos fármacos , Gengiva/citologia , Ácido Glicirretínico/análogos & derivados , Idoso , Apoptose/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/efeitos adversos , Contagem de Células , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , DNA/metabolismo , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Crescimento Excessivo da Gengiva/induzido quimicamente , Crescimento Excessivo da Gengiva/tratamento farmacológico , Ácido Glicirretínico/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Nifedipino/efeitos adversos
4.
J Clin Pharm Ther ; 31(5): 441-6, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16958821

RESUMO

OBJECTIVE: Although all the mechanisms of elimination of hepatitis C virus (HCV) by Interferon (IFN) have not been fully elucidated, the 2'-5'-oligoadenylate (2-5A) system is one of the mechanisms of the antiviral effect of IFN. Consequently, the measurement of 2'-5'-oligoadenylate synthetase (2-5AS) activity could be useful for the evaluation of IFN treatment. This retrospective study was aimed at assessing whether 2-5AS activity functions as a clinical marker of virological response to PEG-interferon-alpha2b (PEG-IFN) plus ribavirin therapy of chronic hepatitis C. METHODS: The 32 patients included in this study had high viral loads of serum HCV-RNA of genotype 1b with chronic hepatitis C. All the patients received a regimen of PEG-IFN plus ribavirin for 48 weeks, and were then divided into two groups: one group (effective group) with undetectable serum HCV-RNA levels at 24 weeks (n = 22) of therapy, the other group (ineffective group) with persistent presence of HCV-RNA in serum at 24 weeks (n = 10). The 2-5AS activity in serum was measured 2, 8 and 12 weeks before initial administration. RESULTS: The 2-5AS response ratio (measured value/measured value of baseline 2-5AS) at 2, 8 and 12 weeks after the administration in the effective group was significantly higher than that in the ineffective group. CONCLUSIONS: These results suggest that the ratio of 2-5AS is closely related to the antiviral effect, and that the measurement of 2-5AS response ratio may be a useful clinical parameter of virological response to PEG-IFN plus ribavirin therapy of chronic hepatitis C.


Assuntos
2',5'-Oligoadenilato Sintetase/metabolismo , Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , 2',5'-Oligoadenilato Sintetase/efeitos dos fármacos , Antivirais/farmacologia , Quimioterapia Combinada , Feminino , Hepacivirus/genética , Hepatite C Crônica/enzimologia , Humanos , Interferon alfa-2 , Interferon-alfa/farmacologia , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/farmacologia , RNA Viral/sangue , Proteínas Recombinantes , Estudos Retrospectivos , Ribavirina/farmacologia
5.
Mol Hum Reprod ; 11(8): 553-9, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16126773

RESUMO

The differentiation of human endometrial epithelium is a dynamic event, which occurs throughout the menstrual cycle in preparation for pregnancy. The appearance of uterodomes (pinopods) in this regard was first introduced in rodents with an established pinocytotic function, whereas little evidence was available in humans in this context. This study was undertaken to identify the potential physiological roles of uterodomes in the implantation process. To address this, endometrial biopsies from early, mid- and late luteal phases of the menstrual cycle of 23 fertile female patients with regular menses were used. Scanning and transmission electron microscopies (SEM and TEM) as well as immunofluorescence and immunogold TEM were performed to study the morphological changes and the expression pattern of leukaemia inhibitory factor (LIF) at uterodomes. Our results illustrated a high level of LIF expression in the human uterodomes, which was colocalized with the well-known biochemical markers of exocytosis, including syntaxin-1, 25-kDa synaptosomal protein (SNAP-25) and vesicle-associated membrane protein-2 (VAMP-2). Our morphological and immunocytochemical findings illustrated a secretory function for human uterodomes for the first time. In conclusion, this novel function for uterodomes provides an important clue in detection of their physiological function(s) during the process of the plasma membrane transformation.


Assuntos
Implantação do Embrião/fisiologia , Endométrio/metabolismo , Interleucina-6/metabolismo , Adulto , Biomarcadores , Endométrio/citologia , Endométrio/ultraestrutura , Exocitose/fisiologia , Feminino , Imunofluorescência , Humanos , Imuno-Histoquímica , Fator Inibidor de Leucemia , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
6.
Pharmacopsychiatry ; 38(1): 30-5, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15706464

RESUMO

OBJECTIVE: The aim of this study was to compare the efficacy and safety profiles between fluvoxamine and nortriptyline in Japanese patients with major depression. METHODS: The efficacy and safety profiles of fluvoxamine, a selective serotonin-reuptake inhibitor, and nortriptyline were compared under a single-blind fashion in 74 Japanese patients with major depression. The efficacy was assessed using the 17-item Hamilton Rating Scale for Depression (HAM-D), Clinical Global Impression Scale (CGI) severity and improvement scores, while the safety profiles were assessed using the UKU Side Effect Rating Scale at baseline, and on days 7, 14, 28 and 56. Moreover, with the aim of determining the distinct efficacy profiles of each drug, the effects on each of the factor scores extracted by the principal component analysis performed for HAM-D scores were compared between drugs. RESULTS: Both drug groups showed significant amelioration of depressive symptomatology over the trial period lasting for 8 weeks. Statistical analyses revealed no significant between-group differences regarding the efficacy assessed by either HAM-D or CGI scores; however, the efficacy of nortriptyline tended to appear earlier than that of fluvoxamine. Moreover, no significant differences were obtained for the factor scores, representing 'depressed mood', 'physical symptoms' or 'sleep disturbances', although 'sleep disturbances' appeared to improve earlier in the nortriptyline group than in the fluvoxamine group. As for the safety profiles, the nortriptyline group scored a significantly higher incidence of adverse events such as dysarthria or orthostatic dizziness, as well as increased heart rate. CONCLUSIONS: These findings suggest that fluvoxamine is generally comparable to nortriptyline in its efficacy and superior in its safety profile, in accordance with findings obtained in previous comparative clinical trials conducted in Caucasian populations.


Assuntos
Antidepressivos de Segunda Geração/uso terapêutico , Antidepressivos Tricíclicos/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Fluvoxamina/uso terapêutico , Nortriptilina/uso terapêutico , Adulto , Idoso , Antidepressivos de Segunda Geração/efeitos adversos , Antidepressivos Tricíclicos/efeitos adversos , Transtorno Depressivo Maior/psicologia , Método Duplo-Cego , Feminino , Fluvoxamina/efeitos adversos , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Nortriptilina/efeitos adversos , Escalas de Graduação Psiquiátrica
7.
Mol Hum Reprod ; 10(2): 91-7, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14742693

RESUMO

The role of integrins in the processes of adhesion and migration makes them attractive potential participants in the complex events of embryo implantation and placentation. Recently, the role of the alpha(v)beta(3)-integrin pathway was shown in the insulin-like growth factor-I (IGF-I)-stimulated migration of extravillous trophoblast (EVT) cells. This study was designed to investigate the role of alpha(5)beta(1)-integrin in this respect. Using cultured EVT cells, migration assays were carried out for IGF-I-treated or untreated cells in the presence or absence of the GRGDSP and GRGESP hexapeptides, alphaIR3, and a blocking antibody against alpha(5)beta(1)-integrin. Immuno-electron microscopy and immunofluorescent staining were performed to localize the distribution of alpha(5)beta(1)- and alpha(v)beta(3)-integrins, Rab5a, paxillin, phospho-FAK (pFAK), and vinculin. The results showed that IGF-I-induced migration of EVT cells was abolished following treatment with GRGDSP hexapeptide, alphaIR3, and a blocking antibody against alpha(5)beta(1)-integrin. Further, statistical analysis showed that the area-related numerical density of the alpha(5)beta(1)-integrin in the perinuclear regions was significantly higher than in the cell extensions. Immunocytochemical experiments demonstrated an up-regulation in internalization rate of alpha(5)beta(1)-integrin in IGF-I-stimulated EVT cells. Furthermore, alpha(5)beta(1)-integrin exhibited co-localization with Rab5a, but not with alpha(v)beta(3)-integrin, pFAK, paxillin, and vinculin at the focal adhesions of the EVT cells. Taken together, these findings suggest an essential role for alpha(5)beta(1)-integrin in IGF-I-promoted migration of EVT cells. It is possible therefore that IGF-I-induced internalization of alpha(5)beta(1)-integrin may be an important event during the migration of EVT cells in the complex processes of implantation and placentation.


Assuntos
Movimento Celular/fisiologia , Implantação do Embrião/fisiologia , Fator de Crescimento Insulin-Like I/farmacologia , Integrina alfa5beta1/fisiologia , Trofoblastos/metabolismo , Movimento Celular/efeitos dos fármacos , Proteínas do Citoesqueleto/análise , Feminino , Imunofluorescência , Humanos , Imuno-Histoquímica , Fator de Crescimento Insulin-Like I/antagonistas & inibidores , Fator de Crescimento Insulin-Like I/metabolismo , Integrina alfa5beta1/análise , Microscopia Confocal , Oligopeptídeos/farmacologia , Paxilina , Fosfoproteínas/análise , Trofoblastos/química , Trofoblastos/efeitos dos fármacos , Vinculina/análise , Proteínas rab5 de Ligação ao GTP/análise
8.
Int J Oral Maxillofac Surg ; 32(1): 97-100, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12653243

RESUMO

A rare case of metastatic hepatocellular carcinoma (HCC) of the maxillary sinus in a 67-year-old man is reported along with the findings at autopsy. A fine needle aspiration biopsy specimen revealed a characteristic tumour structure resembling primary HCC. At autopsy, metastatic lesions were recognized in the bilateral adrenals, spleen, sternum, vertebrae and lymph node at the lesser curvature of the stomach, but not in the lung, suggesting that the HCC had metastasized to the maxillary sinus via the plexus venous vertebralis and/or the azygos vein, or lymph duct. In our reviewed 29 cases of metastatic HCC in the oro-maxillofacial region, most patients were men in the 50- to 70-year age range. At least 11 cases did not have lung metastasis, and in 18, metastasis to the oro-maxillofacial region was the first sign of HCC. One should be aware of the possibility to encounter the oral lesion as first sign of metastatic HCC.


Assuntos
Carcinoma Hepatocelular/secundário , Neoplasias Hepáticas/patologia , Neoplasias do Seio Maxilar/secundário , Neoplasias das Glândulas Suprarrenais/secundário , Idoso , Autopsia , Biópsia por Agulha , Neoplasias Ósseas/secundário , Carcinoma Hepatocelular/patologia , Evolução Fatal , Humanos , Metástase Linfática/patologia , Masculino , Neoplasias do Seio Maxilar/patologia , Neoplasias da Coluna Vertebral/secundário , Neoplasias Esplênicas/secundário
9.
J Mol Med (Berl) ; 80(2): 105-16, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11907647

RESUMO

The recent development of endothelin-1 (ET-1) antagonists and their potential use in the treatment of human disease raises questions as to the role of ET-1 in the pathophysiology of such cardiovascular ailments as hypertension, heart failure, renal failure and atherosclerosis. It is still unclear, for example, whether activation of an endogenous ET-1 system is itself the primary cause of any of these ailments. In that context, the phenotypic manifestations of chronic ET-1 overproduction may provide clues about the tissues and systems affected by ET-1. We therefore established two lines of transgenic mice overexpressing the ET-1 gene under the direction of its own promoter. These mice exhibited low body weight, diminished fur density and two- to fourfold increases in the ET-1 levels measured in plasma, heart, kidney and aorta. There were no apparent histological abnormalities in the visceral organs of young (8 weeks old) transgenic mice, nor was their blood pressure elevated. In aged (12 months old) transgenic mice, however, renal manifestations, including prominent interstitial fibrosis, renal cysts, glomerulosclerosis and narrowing of arterioles, were detected. These pathological changes were accompanied by decreased creatinine clearance, elevated urinary protein excretion and salt-dependent hypertension. It thus appears that mild, chronic overproduction of ET-1 does not primarily cause hypertension but triggers damaging changes in the kidney which lead to the susceptibility to salt-induced hypertension.


Assuntos
Envelhecimento/genética , Endotelina-1/biossíntese , Hipertensão/genética , Hipertensão/fisiopatologia , Nefropatias/genética , Nefropatias/fisiopatologia , Cloreto de Sódio na Dieta/metabolismo , Animais , Pressão Sanguínea/genética , Pressão Sanguínea/fisiologia , Creatinina/sangue , Creatinina/metabolismo , Endotelina-1/sangue , Endotelina-1/genética , Coração/fisiopatologia , Frequência Cardíaca/genética , Frequência Cardíaca/fisiologia , Hipertensão/sangue , Rim/irrigação sanguínea , Rim/fisiopatologia , Rim/ultraestrutura , Nefropatias/sangue , Masculino , Taxa de Depuração Metabólica/genética , Taxa de Depuração Metabólica/efeitos da radiação , Camundongos , Camundongos Transgênicos , Microinjeções/métodos , Microscopia Eletrônica de Varredura , Óvulo/química , Óvulo/crescimento & desenvolvimento , Óvulo/metabolismo , Fenótipo , Transgenes/genética
10.
Circulation ; 104(16): 1964-71, 2001 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-11602502

RESUMO

BACKGROUND: Adrenomedullin (AM) is a vasodilating peptide involved in the regulation of circulatory homeostasis and in the pathophysiology of certain cardiovascular diseases. Levels of AM are markedly increased in the fetoplacental circulation during pregnancy, although its function there remains unknown. To clarify the physiological functions of AM, we chose a gene-targeting strategy in mice. METHODS AND RESULTS: Targeted null mutation of the AM gene is lethal in utero: the mortality rate among AM(-/-) embryos was >80% at E13.5. The most apparent abnormality in surviving AM(-/-) embryos at E13.5 to E14.0 was severe hemorrhage, readily observable under the skin and in visceral organs. Hemorrhage was not detectable at E12.5 to E13.0, although the yolk sac lacked well-developed vessels. Electron microscopic examination showed endothelial cells to be partially detached from the basement structure at E12.5 in vitelline vessels and hepatic capillaries, which allowed efflux of protoerythrocytes through the disrupted barrier. The basement membrane was not clearly recognizable in the aorta and cervical artery, and the endothelial cells stood out from the wall of the lumen, only partially adhering to the basement structure. AM(+/-) mice survived to adulthood but exhibited elevated blood pressures with diminished nitric oxide production. CONCLUSIONS: AM is indispensable for the vascular morphogenesis during embryonic development and for postnatal regulation of blood pressure by stimulating nitric oxide production.


Assuntos
Vasos Sanguíneos/anormalidades , Anormalidades Cardiovasculares/patologia , Hipertensão/patologia , Peptídeos/deficiência , Adrenomedulina , Animais , Vasos Sanguíneos/patologia , Vasos Sanguíneos/ultraestrutura , Perda do Embrião/etiologia , Perda do Embrião/patologia , Endotélio Vascular/embriologia , Endotélio Vascular/patologia , Endotélio Vascular/ultraestrutura , Feminino , Marcação de Genes , Genes Letais , Genótipo , Hemodinâmica/genética , Hemorragia/embriologia , Hemorragia/genética , Hemorragia/patologia , Heterozigoto , Homozigoto , Hipertensão/genética , Hipertensão/fisiopatologia , Endogamia , Bombas de Infusão , Injeções Subcutâneas , Masculino , Camundongos , Camundongos Knockout , Óxido Nítrico/metabolismo , Peptídeos/administração & dosagem , Peptídeos/genética , Fenótipo , Proteínas Recombinantes/administração & dosagem , Membrana Vitelina/irrigação sanguínea , Membrana Vitelina/embriologia , Membrana Vitelina/patologia
11.
J Histochem Cytochem ; 49(10): 1311-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11561016

RESUMO

The histochemical distribution of sialoglycoconjugates in the CA1 region in the hippocampus formation of 9-week-old rats and 30-month-old rats was examined using electron microscopy in combination with two lectins, Maackia amurensis lectin, specific for Sia(alpha)2-3Gal, and Sambucus sieboldiana agglutinin, specific for Sia(alpha)2-6Gal. Each lectin stained the plasma membranes of pyramidal cells, indicating that the Sia(alpha)2-3Gal and Sia(alpha)2-6Gal groups were expressed on their plasma membranes. These lectins also bound to synapses in the stratum lacunosum molecular. The staining intensity of the lectins in the synapses in these layers was downregulated in the 30-month-old rats. These results indicated that both the Sia(alpha)2-3Gal and Sia(alpha)2-6Gal groups are expressed on these synapses and that the expression of these sialyl linkages decreases in the aged brain


Assuntos
Envelhecimento/metabolismo , Hipocampo/metabolismo , Sialoglicoproteínas/metabolismo , Animais , Giro Denteado/metabolismo , Giro Denteado/ultraestrutura , Regulação para Baixo , Feminino , Hipocampo/anatomia & histologia , Hipocampo/ultraestrutura , Lectinas , Microscopia Eletrônica , Ratos , Ratos Endogâmicos F344 , Sinapses/metabolismo
12.
Arch Biochem Biophys ; 389(2): 166-75, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11339805

RESUMO

Hyperglycemia leads to vascular disease specific to diabetes mellitus. This pathology, which results from abnormal proliferation of smooth muscle cells in arterial walls, may lead to cataract, renal failure, and atherosclerosis. The hexosamine biosynthetic pathway is exquisitely responsive to glucose concentration and plays an important role in glucose-induced insulin resistance. UDP-GlcNAc: polypeptide O-N-acetylglucosaminyltransferase (O-GlcNAc transferase; OGTase) catalyzes the O-linked attachment of single GlcNAc moieties to serine and threonine residues on many cytosolic or nuclear proteins. Polyclonal antibody against OGTase was used to examine the expression of OGTase in rat aorta and aortic smooth muscle (RASM) cells. OGTase enzymatic activity and expression at the mRNA and protein levels were determined in RASM cells cultured at normal (5 mM) and at high (20 mM) glucose concentrations. OGTase mRNA and protein are expressed in both endothelial cells and smooth muscle cells in the aorta of normal rats. In both cell types, the nucleus is intensely stained, while the cytoplasm stains diffusely. Immunoelectron microscopy shows that OGTase is localized to euchromatin and around the myofilaments of smooth muscle cells. In RASM cells grown in 5 mM glucose, OGTase is also located mainly in the nucleus. Hyperglycemic RASM cells also display a relative increase in OGTase's p78 subunit and an overall increase protein and activity for OGTase. Biochemical analyses show that hyperglycemia qualitatively and quantitatively alters the glycosylation or expression of many O-GlcNAc-modified proteins in the nucleus. These results suggest that the abnormal O-GlcNAc modification of intracellular proteins may be involved in glucose toxicity to vascular tissues.


Assuntos
Hiperglicemia/enzimologia , Hiperglicemia/genética , Músculo Liso Vascular/enzimologia , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo , Animais , Células Cultivadas , Expressão Gênica , Hiperglicemia/metabolismo , Imuno-Histoquímica , Microscopia Imunoeletrônica , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos
13.
Biochem Biophys Res Commun ; 280(4): 1055-61, 2001 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-11162634

RESUMO

Using a degenerate RT-PCR-based screening method, we isolated the homeobox gene, Gbx1, from the shank skin of 13-day-old chick embryos. By in situ hybridization analysis we showed that the Gbx1 was expressed in the epidermis of the skin and the mucous epithelium of the intestine, and that among many homeobox genes isolated, expression of the Gbx1 strongly increased in the epidermis when the skin was cultured with 20 microM retinol, which induces epidermal mucous metaplasia. The Gbx1 expression in the epidermis was increased by interaction with the retinol-pretreated dermal fibroblasts, resulting in mucous metaplasia. These results suggest that the Gbx1 regulates the differentiation and transdifferentiation of the epithelium and controls the morphology of the epithelium. We isolated the chick Gbx1 cDNA clones. The amino acid sequences in homeodomain and its downstream encoded by human and chick Gbx1 cDNA were almost the same, but those upstream of the homeodomain were rather different.


Assuntos
Epiderme/metabolismo , Genes Homeobox/genética , Proteínas de Homeodomínio/biossíntese , Metaplasia/metabolismo , Mucosa/patologia , Vitamina A/farmacologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Diferenciação Celular , Células Cultivadas , Embrião de Galinha , DNA Complementar/metabolismo , Relação Dose-Resposta a Droga , Fibroblastos/metabolismo , Hibridização In Situ , Mucosa Intestinal/metabolismo , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Pele/metabolismo , Fatores de Tempo
14.
J Oral Sci ; 43(4): 261-8, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11848193

RESUMO

Our previous study indicated that fibroblasts derived from patients reactive to nifedipine might be susceptible to the other calcium-channel blockers (nicardipine, verapamil and diltiazem) in terms of cell proliferation, DNA synthesis, and collagen synthesis. Thus, the present investigation was designed to clarify the cross-reactivity among dihydropyridine calcium-channel blockers (nifedipine, nicardipine, and nisoldipine). Human gingival fibroblasts derived from seven, two, and one patients who developed gingival overgrowth as a result of nifedipine, nicardipine, and nisoldipine medications, respectively, were examined in terms of the effect of calcium-channel blockers (nifedipine, diltiazem, verapamil, and nicardipine) on cell proliferation, DNA synthesis, collagen synthesis, and the number of epidermal growth factor (EGF) receptors. Phenytoin was used as a positive control. With most of the calcium-channel blockers and phenytoin, fibroblasts from patients reactive to nifedipine and nicardipine medications gave a better cell proliferation rate, DNA synthesis, and an increased number of EGF receptors, compared to non-drug-treated control. However, this was not the case for calcium-channel blockers tested in fibroblasts from patients reactive to nisoldipine medication.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Colágeno/efeitos dos fármacos , DNA/efeitos dos fármacos , Receptores ErbB/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Gengiva/efeitos dos fármacos , Crescimento Excessivo da Gengiva/induzido quimicamente , Nicardipino/efeitos adversos , Nifedipino/efeitos adversos , Nisoldipino/efeitos adversos , Adulto , Idoso , Análise de Variância , Anticonvulsivantes/farmacologia , Bloqueadores dos Canais de Cálcio/efeitos adversos , Técnicas de Cultura de Células , Divisão Celular/efeitos dos fármacos , Colágeno/biossíntese , DNA/biossíntese , Diltiazem/farmacologia , Feminino , Citometria de Fluxo , Gengiva/patologia , Crescimento Excessivo da Gengiva/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Nicardipino/farmacologia , Nifedipino/farmacologia , Fenitoína/farmacologia , Compostos Radiofarmacêuticos , Estatística como Assunto , Trítio , Verapamil/farmacologia
15.
Diabetologia ; 43(10): 1239-47, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11079742

RESUMO

AIMS/HYPOTHESIS: Streptozotocin (STZ), a chemically reactive analogue of N-acetylglucosamine, induces necrosis of the beta cells, resulting in diabetes mellitus. Glucose-induced insulin resistance is mediated by increased activity of the hexosamine pathway. We aimed to examine the regulation of O-GlcNAc transferase expression and activity in the normal and streptozotocin diabetic pancreas. METHODS: Rats were made diabetic by an injection of streptozotocin (65 mg/kg). The expression of O-GlcNAc transferase protein was examined by immunoblot analysis. Activity of O-GlcNAc transferase was assayed by the incorporation of [3H]GlcNAc into the synthetic peptide. Localization of O-GlcNAc transferase was done by immunohistochemistry. The change of O-GlcNAc modification of proteins was examined by immunoblot analysis. RESULTS: In the STZ-induced diabetic pancreas, a severe loss of beta cells was observed, whereas alpha cells had increased in number. The diabetic pancreas showed an increase in the expression of O-GlcNAc transferase at the protein level and the O-GlcNAc transferase activity in it was increased significantly (p < 0.05). An increase in the immunostaining intensity in the cytoplasm of islet beta cells was also observed in the diabetic pancreas, whereas exocrine cells and islet cells other than beta cells showed little change in immunostaining intensity. The pancreas of STZ-diabetic rats showed a 3.1-fold increase in total cellular O-GlcNAc-modified proteins. CONCLUSION/INTERPRETATION: These findings indicate that O-GlcNAc transferase plays an important part in the modulation of O-GlcNAc concentrations in the pancreas and suggest that the increase in O-GlcNAc modification of the proteins correlates closely with diabetes.


Assuntos
Diabetes Mellitus Experimental/enzimologia , N-Acetilglucosaminiltransferases/metabolismo , Pâncreas/enzimologia , Animais , Western Blotting , Imunofluorescência , Immunoblotting , Masculino , Microscopia de Fluorescência , N-Acetilglucosaminiltransferases/análise , Proteínas/metabolismo , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
16.
Biochem Biophys Res Commun ; 276(3): 1112-7, 2000 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-11027598

RESUMO

We performed in situ hybridization and immunohistochemical analysis of HB9 homeobox gene mRNA and protein, respectively, during chick feather development. HB9 mRNA was highly expressed in epidermal basal cells and dermal cells of the placodes and feather buds, but not in those of the interplacodes and interbud regions. HB9 protein was predominantly expressed in dermal cells of the symmetric short buds and decreased after the asymmetric bud stage when the feather bud had become elongated along the anterior-posterior (A-P) and proximal-distal (P-D) axis. These results suggest that HB9 gene is regulated in a spatiotemporal manner during feather development, and may be involved in early feather bud morphogenesis.


Assuntos
Plumas/embriologia , Plumas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/análise , Proteínas de Homeodomínio/genética , Fatores de Transcrição/análise , Fatores de Transcrição/genética , Animais , Elementos Antissenso (Genética) , Divisão Celular , Embrião de Galinha , Derme/citologia , Derme/embriologia , Derme/metabolismo , Células Epidérmicas , Epiderme/embriologia , Epiderme/metabolismo , Perfilação da Expressão Gênica , Imuno-Histoquímica , Hibridização In Situ , Morfogênese , RNA Mensageiro/análise , RNA Mensageiro/genética
17.
Histochem J ; 32(5): 275-80, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10939514

RESUMO

A homeobox gene, HB9, has been isolated from the tarsometatarsal skin of 13-day-old chick embryos using a degenerate RT-PCR-based screening method. In situ hybridization analysis revealed that, during development of chick embryonic skin, the HB9 gene was expressed in epidermal basal cells of the placodes, but not in those of interplacodes, and in the dermal cells under the placodes at 9 days before addition of an intermediate layer by proliferation of the basal cells in the placodes. With the onset of epidermal stratification, the direction of the basal cell mitosis changed, with the axis becoming vertical to the epidermal surface. Placodes and interplacodes form outer and inner scales, respectively, after they have elongated distally (Tanaka S, Kato Y (1983b) J Exp Zool 225: 271-283). During scale ridge elongation at 12-15 days, HB9 was strongly expressed in the epidermis of the outer scale face, where the cell proliferation is more active than in the epidermis of the inner scale face; hence, stratification of the outer scale face is more prominent than that of the inner scale face. After 16 days, when mitotic activity in the epidermal basal cells decreases and the thickness of the epidermis is maintained at a constant level, the HB9 expression decreases with the onset of epidermal keratinization. These results suggest that HB9 may be involved in the proliferation of the epidermal basal cells that accompanies epidermal stratification.


Assuntos
Genes Homeobox , Proteínas de Homeodomínio/genética , Pele/embriologia , Fatores de Transcrição/genética , Animais , Divisão Celular , Embrião de Galinha , Epiderme/embriologia , Epiderme/metabolismo , Epiderme/patologia , Expressão Gênica , Pele/metabolismo , Pele/patologia
18.
Exp Cell Res ; 258(2): 261-9, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10896777

RESUMO

The human immunodeficiency virus type 1 (HIV-1) accessory protein Vpr induces cell cycle arrest in the G2 phase of the cell cycle followed by apoptosis. The mechanism of the arrest is unknown but the arrest is believed to facilitate viral replication. In the present study, we have established cell lines that allow conditional expression of Vpr, and have examined the mechanism of cell death following Vpr expression. We found that cells expressing Vpr enter M phase after long G2 arrest but formed aberrant multipolar spindles that were incapable of completing karyokinesis or cytokinesis. This abnormality provided the basis for apoptosis, which always followed in these cells. The multipolar spindles formed in response to abnormal centrosomal duplication that occurred during the G2 arrest but did not occur in cells arrested in G2 by irradiation. Thus, the expression of Vpr appears to be responsible for abnormal centrosome duplication, which in turn contributes in part to the rapid cell death following HIV-1 infection.


Assuntos
Apoptose , Produtos do Gene vpr/fisiologia , HIV-1/fisiologia , Divisão Celular , Linhagem Celular Transformada , Núcleo Celular/virologia , Centrossomo/virologia , Fase G2 , Produtos do Gene vpr/biossíntese , Produtos do Gene vpr/genética , Células HeLa , Humanos , Metáfase , Mitose , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Produtos do Gene vpr do Vírus da Imunodeficiência Humana
19.
Microbios ; 101(399): 105-14, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10738983

RESUMO

It was reported previously that supernatants of cultures of Bacillus mesentericus TO-A promote the growth of Bifidobacterium species. In this study, a new growth-promoting factor, BM-1, was purified from the supernatant of such a culture and its chemical structure was determined. BM-1 was identified as 3,3-dihydroxyazetidine, and it promoted the growth of several strains of Bifidobacterium.


Assuntos
Azetidinas/isolamento & purificação , Bacillus/química , Bifidobacterium/efeitos dos fármacos , Azetidinas/farmacologia , Técnicas Bacteriológicas , Bifidobacterium/crescimento & desenvolvimento , Cromatografia em Agarose , Cromatografia por Troca Iônica , Fatores de Tempo
20.
J Clin Pharmacol ; 40(3): 284-9, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10709157

RESUMO

The authors investigated whether theophylline metabolism is decreased in asthmatic patients and what condition may be related to its reduction. Fifty-two children with asthma were given 15 mg/kg/day aminophylline intravenously at a constant rate. Blood and spot urine samples were collected at 24 hours, 48 hours, and 72 hours after beginning infusion. The ratio of plasma theophylline concentration at 72 hours to that at 24 hours (C72h/C24h) varied from 0.42 to 1.51 (average 0.894). Plasma theophylline concentration of patients with lower C72h/C24h than average reduced significantly, while the concentration of those with higher C72h/C24h remained unchanged. The urinary ratio of the sum of the metabolites to theophylline was significantly increased in the patients with the lower ratio. Among the demographic characteristics examined, significant difference was found only in the incidence of patients with C-reactive protein (CRP) of 0.5 mg/dl or greater or patients with a fever of 37.5 degrees C or greater when admitted. Acute febrile illness accompanied by increased CRP level may affect theophylline metabolism.


Assuntos
Asma/metabolismo , Broncodilatadores/metabolismo , Proteína C-Reativa/metabolismo , Febre/induzido quimicamente , Teofilina/metabolismo , Adolescente , Asma/tratamento farmacológico , Broncodilatadores/sangue , Broncodilatadores/urina , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Infusões Intravenosas , Masculino , Teofilina/efeitos adversos , Teofilina/sangue , Teofilina/urina
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