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1.
Clin Genet ; 87(1): 80-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24266672

RESUMO

Mandibulofacial dysostosis with microcephaly (MFDM) is a sporadic malformation syndrome with severe craniofacial abnormalities, microcephaly, developmental delay, and dysmorphic features. Most cases of clinically diagnosed MFDM remain genetically unexplained, and to the best of our knowledge a total of 35 patients, 31 different mutations, 4 deletions, and 6 reports have been published. Our proband was born at 36 weeks gestation with microcephaly, microcrania, cleft palate, severe retrognathia, oral and pharyngeal dysphagia, bilateral proximal radioulnar synostosis, 11 thoracic ribs, abnormal magnetic resonance imaging (MRI) findings including simplified gyral pattern and mild dilatation of the posterior bodies of the lateral ventricles secondary to thinning of the white matter, high-pitched cry due to unilateral vocal cord paralysis, and dysmorphic features. Array comparative genomic hybridization (aCGH) + single nucleotide polymorphism (SNP) analysis identified a likely de novo pathogenic deletion on chromosome 17q21.31, encompassing the EFTUD2 gene. Our case represents the fifth reported proband to have MFDM caused by small deletions involving EFTUD2. All known mutations involving EFTUD2 result in genetic haploinsufficiency, consistent with our proband's case as well. Her phenotypic features both overlap and expand on the clinical features of previously reported cases, and her genetic diagnosis also supports the use of aCGH as a first-tier testing option for this disorder.


Assuntos
Anormalidades Múltiplas/genética , Cromossomos Humanos Par 17/genética , Hibridização Genômica Comparativa/métodos , Disostose Mandibulofacial/genética , Microcefalia/genética , Fatores de Alongamento de Peptídeos/genética , Ribonucleoproteína Nuclear Pequena U5/genética , Anormalidades Múltiplas/diagnóstico , Deficiências do Desenvolvimento/genética , Feminino , Humanos , Disostose Mandibulofacial/diagnóstico , Análise em Microsséries , Microcefalia/diagnóstico , Polimorfismo de Nucleotídeo Único/genética , Deleção de Sequência/genética
3.
Orthod Craniofac Res ; 14(4): 234-42, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22008303

RESUMO

OBJECTIVE: The objective of this study is to examine the effect of cyclosporine-A (CsA) on the rate of orthodontic tooth movement in rats. SETTING AND SAMPLE POPULATION: This is a randomized controlled trial with a split-mouth design in Sprague-Dawley rats. MATERIAL AND METHODS: Eighteen rats, divided at random in two groups, were fed with 8 mg/kg CsA (experiment) or mineral oil (control) daily after initial healing of bilateral maxillary second molar removal. All rats received orthodontic coil springs (10 cN) secured to the maxillary incisors and first molars at the rights side, while no springs were placed at the left. Distances between first and third molars were measured on days 0, 3, 6, and 12. After sacrificing on day 12, the alveolar ridges of the maxillae were sectioned and blood samples were collected for serum tartrate-resistant acid phosphatase (TRAP)-5b level detection and for histology, respectively. RESULTS: Significantly larger changes in intermolar distances were found after orthodontic force application in the CsA group at days 3 and 12 when compared with the control group. The inter-radicular dental alveolus of CSA-fed rats was osteopenic. Significantly increased TRAP-5b serum level was noted in the CsA group when compared with the control group. CONCLUSIONS: We suggest that CsA enhanced the rate of orthodontic tooth movement. The osteopenia and the increased osteoclastic activity could be the underlying factors.


Assuntos
Ciclosporina/farmacologia , Imunossupressores/farmacologia , Técnicas de Movimentação Dentária/métodos , Fosfatase Ácida/análise , Processo Alveolar/efeitos dos fármacos , Processo Alveolar/patologia , Animais , Biomarcadores/análise , Doenças Ósseas Metabólicas/patologia , Remodelação Óssea/efeitos dos fármacos , Isoenzimas/análise , Masculino , Maxila/efeitos dos fármacos , Maxila/patologia , Dente Molar/efeitos dos fármacos , Dente Molar/patologia , Fios Ortodônticos , Osteoclastos/efeitos dos fármacos , Osteoclastos/patologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Estresse Mecânico , Fosfatase Ácida Resistente a Tartarato , Fatores de Tempo , Técnicas de Movimentação Dentária/instrumentação
4.
Nanotechnology ; 20(39): 395705, 2009 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-19724108

RESUMO

Nanocomposites, such as polymer blending with carbon nanotubes (CNTs), have been shown to have a drastic reduction in the resistivity and become conductive when the CNTs concentration has reached a certain percolation threshold. The reduction could be more than a millionth of the original polymer material. This has been realized as the formation of an infinite cluster of connected CNTs or pathways. Therefore, the conductivity of a nanocomposite should follow that of CNTs. Here we show that the resistivity of a nanocomposite is not governed by the interconnected CNTs, but the polymer between neighboring CNTs. That is, polymer-CNTs exhibit the nature of a conducting polymer, which can be explained as the tunneling of electrons one by one from the first CNT electrode to the next-nearest CNT electrode, forming a CNT/polymer pathway. A conduction model based on the tunneling of electrons passing, one by one, through the polymer gap between two neighboring CNT electrodes is formulated and derived. This model can accurately predict the significant reduction of the polymer-CNTs' resistivity with the addition of CNTs. The temperature effect can be readily incorporated to account for resistivity variation with the temperature of this nanocomposites.

5.
Nanotechnology ; 20(18): 185503, 2009 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-19420615

RESUMO

Polyimide (PI)-carbon nanotube composites were fabricated by in situ polymerization using multi-wall carbon nanotubes (MWNT) as fillers. The composite film was characterized by some analytical instruments to ensure its structure and good dispersion of the MWNTs in the composites. The electrical resistivity of this composite was found to vary significantly with both the temperature and the stress in the material. The PI-MWNT composites possess a very linear piezoresistive nature which can be used as a good pressure sensor material, provided with proper temperature compensation. Fabrication of a micropolymer pressure sensor using this nanocomposite sensing material is demonstrated and sensor performance is evaluated. The sensor has a higher sensitivity than a polysilicon sensor, rapid response, and is thermally stable. The sensor is suitable for mass production, and can be widely applied or integrated in a microfluidic system or biochip where pressure information is required.


Assuntos
Cristalização/métodos , Manometria/instrumentação , Sistemas Microeletromecânicos/instrumentação , Nanotecnologia/instrumentação , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Transdutores , Desenho de Equipamento , Análise de Falha de Equipamento , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Pressão , Resinas Sintéticas/química , Propriedades de Superfície
6.
J Periodontal Res ; 44(3): 338-47, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19210333

RESUMO

BACKGROUND AND OBJECTIVE: Membrane type-I matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase-2 (TIMP-2) regulate the activation of MMP-2; however, their roles in the activation of MMP-2 in gingiva during treatment with cyclosporine A are still unknown. Therefore, the expressions of membrane type-I MMP and TIMP-2, as well as MMP-2, in gingivae upon treatment with cyclosporine A were examined in vivo and in vitro. MATERIAL AND METHODS: Thirty-four rats were divided into two groups after edentulous ridges were established. The experimental group received 30 mg/kg/d of cyclosporine A and the control group received vehicle. At the end of the experimental period, the rats were killed, the gingivae were obtained and the expression of mRNA and protein of membrane type-I MMP, TIMP-2 and MMP-2 in gingiva were examined using real-time polymerase chain reaction and immunohistochemistry. In human gingival fibroblasts, the activity of MMP-2 and the expression of MMP-2, membrane type-I MMP and TIMP-2 mRNAs were examined (using zymography and reverse transcription-polymerase chain reaction, respectively) after treatment with cyclosporine A. RESULTS: In gingivae of rats, cyclosporine A significantly decreased the expression of mRNA and protein of membrane type-I MMP, but not of TIMP-2. The expression of MMP-2 mRNA was unaffected but the expression of MMP-2 protein showed a significant decrease upon treatment with cyclosporine A. In fibroblast culture medium, the presence of cyclosporine A induced a decrease in MMP-2 activity in a dose-dependent manner. The expression of MMP-2, membrane type-I MMP and TIMP-2 mRNAs in fibroblasts was not significantly affected by cyclosporine A; however, in fibroblasts the ratio of mRNA expression of membrane type-I MMP to that of TIMP-2 decreased as the cyclosporine A dose was increased. CONCLUSION: Cyclosporine A inhibits the expression of membrane type-I MMP in gingiva and it may further reduce the activation of MMP-2.


Assuntos
Ciclosporina/farmacologia , Gengiva/enzimologia , Imunossupressores/farmacologia , Inibidores de Metaloproteinases de Matriz , Inibidores de Proteases/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Expressão Gênica/efeitos dos fármacos , Gengiva/citologia , Gengiva/efeitos dos fármacos , Crescimento Excessivo da Gengiva/induzido quimicamente , Crescimento Excessivo da Gengiva/enzimologia , Humanos , Masculino , Metaloproteinase 1 da Matriz/biossíntese , Metaloproteinase 14 da Matriz/biossíntese , Metaloproteinase 2 da Matriz/biossíntese , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Inibidor Tecidual de Metaloproteinase-2/biossíntese
7.
Nanotechnology ; 19(10): 105303, 2008 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-21817696

RESUMO

This study presents the synthesis of a dense single-wall carbon nanotube (SWNT) network on a silicon substrate using alcohol as the source gas. The nanosize catalysts required are made by the reduction of metal compounds in ethanol. The key point in spreading the nanoparticles on the substrate, so that the SWNT network can be grown over the entire wafer, is making the substrate surface hydrophilic. This SWNT network is so dense that it can be treated like a thin film. Methods of patterning this SWNT film with integrated circuit compatible processes are presented and discussed for the first time in the literature. Finally, fabrication and characteristic measurements of a field effect transistor (FET) using this SWNT film are also demonstrated. This FET is shown to have better electronic properties than any other kind of thin film transistor. This thin film with good electronic properties can be readily applied in the processing of many other SWNT electronic devices.

8.
Int Endod J ; 40(1): 11-7, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17209827

RESUMO

AIM: To investigate the influence of the size and the depth of insertion of irrigating needles, and the diameter of the master apical file on flow distribution during fluid irrigation in root canals. METHODOLOGY: Stepback canal instrumentation was employed on seven extracted human single canal teeth. The size of the master apical files ranged from sizes 25, 30, 35, 40, 45, 50 to size 80 within the seven teeth, respectively. A thermal imaging system (ThermaCAM; National Instruments Co., Austin, TX, USA) was used to record the dynamic fluid distribution following root canal preparation. The dynamic fluid distribution was analysed during irrigation by insertion of different irrigating needle tips (23, 25 and 27 gauge) at various depths (3, 6 and 9 mm) from the root apex. The whole process of irrigation was recorded by a video camera and analysed by two observers separately. The success of the irrigation process was defined when the irrigant was able to flow into to the apical region immediately after injection. RESULTS: The aqueous irrigant was flushed into the apical region when a size 27 gauge irrigating needle was placed into a size 30 canal at a point 3 mm from the apical stop. When the same needle tip was placed 6 mm from the root canal apex, successful irrigation was achieved only in the canals prepared to size 50 or larger. When a size 25 gauge irrigating needle was placed 3 mm from the working length, the canal size had to be no <45 to allow for successful irrigation. When a size 23 gauge needle was placed at the same position, the canal needed to be prepared to size 50 to allow thorough irrigation of the apex. At 9 mm from the apical stop, none of the irrigating needles could achieve successful irrigation of any canal size. CONCLUSION: The flow distribution of root canal irrigation can be affected adversely by large diameter irrigating needles, by greater distances between the needle tip and the apical stop, and by narrow root canals.


Assuntos
Irrigantes do Canal Radicular/administração & dosagem , Preparo de Canal Radicular/instrumentação , Cavidade Pulpar , Humanos , Modelos Teóricos , Agulhas , Reologia , Gravação em Vídeo
9.
Drug Dev Ind Pharm ; 32(6): 651-60, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16885120

RESUMO

A convenient and reliable method to prepare procaterol HCl oral dosage form at an extremely low dosage (25 microg/cap) is presented in this paper. Procaterol HCl was mixed with the film-forming agent hydroxypropyl methylcellulose in an aqueous solution, which was then spray-coated on sugar spheres (Nu-pareil PG 20/25) to produce procaterol HCl pellets. The IR spectra of coated and noncoated pellets indicated that procaterol HCl was coated on the sugar spheres successfully with a weight increment less than 1%. Most of the coated pellets were able to pass through an 18-mesh screen with no agglomeration. The average weights of coated pellets filled inside of capsules were monitored during the filling process. A simple liquid chromatographic method was developed and validated for the assay and uniformity test of procaterol HCl in different dosage forms. The results of assay and content uniformity test for both in-house product and a commercial product, i.e., Meptin-mini tablet, were satisfied. The data of f(2) function and ANOVA analysis for the dissolution profiles of both procaterol HCl products suggested that they are pharmaceutical equivalent. In an in vivo study (n = 24), a single dose of 75 microg procaterol HCl was administrated to each volunteer and the plasma concentration of procaterol was determined by a LC/MS/MS method, developed by the same authors. There were no significant differences (p > 0.05) in the data of AUC(0-->16 h), AUC(0-->infinity), C(max), and MRT for both preparations. It is confirmed that the pellets capsule produced in this study is bioequivalent with Meptin-mini tablet.


Assuntos
Agonistas Adrenérgicos beta/farmacocinética , Procaterol/farmacocinética , Tecnologia Farmacêutica , Administração Oral , Agonistas Adrenérgicos beta/administração & dosagem , Agonistas Adrenérgicos beta/química , Adulto , Cápsulas , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Humanos , Masculino , Procaterol/administração & dosagem , Procaterol/química , Controle de Qualidade , Solubilidade , Comprimidos , Equivalência Terapêutica
10.
Int J Oral Maxillofac Surg ; 34(7): 782-8, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15979850

RESUMO

Healing after tooth extraction was studied in rats treated with cyclosporine-A (CSA) for four weeks. Sixty male Sprague-Dawley rats were assigned to one of three groups of 20 rats each. The maxillary right molars were extracted from two groups; the third group served as a non-extraction control. The non-extraction group and one extraction group (vehicle control) received the solvent mineral oil daily, and the other extraction group received 15 mg/kg CSA in mineral oil. Five rats from each group were killed 5, 10, 14 and 28 days after extraction and samples analyzed histologically. On days 5 and 10, bone volume was significantly lower and marrow volume significantly higher in both extraction groups than in the non-extraction group. The fractional-formation surfaces were significantly lower in the extraction groups than in the non-extraction group on day 5 only. Osteoid volume was significantly higher in the extraction vehicle control group than in the other two groups on days 10 and 14; however, the osteoid volume was higher in the CSA group than in the other two groups on day 28. On days 14 and 28, bone volume was lower and marrow volume higher in the CSA group than in the extraction vehicle control and non-extraction groups. On day 28, bony surface areas were significantly greater in the CSA group than in the extraction vehicle control and non-extraction groups. Soft-tissue evaluation showed significantly greater epithelial areas, connective tissue areas and total tissue areas in the CSA group than in the extraction vehicle control group on day 28, but not on day 14. These data suggest that CSA may influence healing of both the gingival tissue and the alveolar bony sockets in the tooth-extraction wound. Further detailed study is needed to identify the mechanisms responsible.


Assuntos
Ciclosporina/farmacologia , Gengiva/efeitos dos fármacos , Imunossupressores/farmacologia , Alvéolo Dental/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Processo Alveolar/efeitos dos fármacos , Animais , Densidade Óssea/efeitos dos fármacos , Medula Óssea/efeitos dos fármacos , Tecido Conjuntivo/efeitos dos fármacos , Epitélio/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Extração Dentária
11.
Biosens Bioelectron ; 20(1): 91-101, 2004 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-15142581

RESUMO

The current work provides a design and fabrication technique for a micro channel system that can provide a uniform heat flux boundary condition on the channel wall and a well insulation on the wall to prevent heat loss from the channel to the outside ambient. Therefore, detailed micro-scale flow and heat transfer process and information along the channel can be studied. Semiconductor sensor material was selected to fabricate both the heaters and the arrays of temperature sensors on a silicon substrate. These heaters and sensors were then moved to a low thermal conductivity epoxy-glass substrate for fabrication of the channel. Design consideration and fabrication techniques involved in this processes will be discussed. A final measurement for the validation of the heaters and the sensors fabricated and a study of the flow friction behavior and the heat transfer coefficient distributions inside the micro channel will be presented. The local Nusselt number distrubution inside the micro channel is reported the first time in the open literature.


Assuntos
Análise de Injeção de Fluxo/instrumentação , Calefação/instrumentação , Temperatura Alta , Técnicas Analíticas Microfluídicas/instrumentação , Termografia/instrumentação , Transdutores , Desenho de Equipamento , Análise de Falha de Equipamento , Análise de Injeção de Fluxo/métodos , Calefação/métodos , Técnicas Analíticas Microfluídicas/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Condutividade Térmica , Termografia/métodos
12.
Biosens Bioelectron ; 20(1): 103-14, 2004 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-15142582

RESUMO

The design and fabrication for a thermal chip with an array of temperature sensors and heaters for study of micro-jet impingement cooling heat transfer process are presented. This thermal chip can minimize the heat loss from the system to the ambient and provide a uniform heat flux along the wall, thus local heat transfer processes along the wall can be measured and obtained. The fabrication procedure presented can reach a chip yield of 100%, and every one of the sensors and heaters on the chip is in good condition. In addition, micro-jet impingement cooling experiments are performed to obtain the micro-scale local heat transfer Nusselt number along the wall. Flow visualization for the micro-impinging jet is also made. The experimental results indicate that both the micro-scale impinging jet flow structure and the heat transfer process along the wall is significantly different from the case of large-scale jet impingement cooling process.


Assuntos
Temperatura Baixa , Análise de Injeção de Fluxo/instrumentação , Calefação/instrumentação , Temperatura Alta , Técnicas Analíticas Microfluídicas/instrumentação , Termografia/instrumentação , Transdutores , Desenho de Equipamento , Análise de Falha de Equipamento , Análise de Injeção de Fluxo/métodos , Calefação/métodos , Técnicas Analíticas Microfluídicas/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Condutividade Térmica , Termografia/métodos
13.
Cell Mol Life Sci ; 58(11): 1636-49, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11706990

RESUMO

Protein farnesylation, catalyzed by protein farnesyltransferase, plays important roles in the membrane association and protein-protein interaction of a number of eukaryotic proteins. Recent development of farnesyltransferase inhibitors (FTIs) has led to further insight into the biological significance of farnesylation in cancer cells. A number of reports point to the dramatic effects FTIs exert on cancer cells. In addition to inhibiting anchorage-independent growth, FTIs cause changes in the cell cycle either at the G1/S or at the G2/M phase. Furthermore, induction of apoptosis by FTIs has been reported. FTIs also affects the actin cytoskeleton and cell morphology. This review summarizes these reports and discusses implications for farnesylated proteins responsible for these FTI effects.


Assuntos
Alquil e Aril Transferases/metabolismo , Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Neoplasias/patologia , Prenilação de Proteína , Alquil e Aril Transferases/antagonistas & inibidores , Animais , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Tamanho Celular , Proteínas Cromossômicas não Histona/metabolismo , Inibidores Enzimáticos/uso terapêutico , Farnesiltranstransferase , Humanos , Estrutura Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Fibras de Estresse/metabolismo , Células Tumorais Cultivadas , Proteínas ras/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo
14.
J Biol Chem ; 276(45): 42259-67, 2001 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-11533059

RESUMO

Using microarray analysis, we identified a unique ras superfamily gene, termed RERG (ras-related and estrogen-regulated growth inhibitor), whose expression was decreased or lost in a significant percentage of primary human breast tumors that show a poor clinical prognosis. Importantly, high RERG expression correlated with expression of a set of genes that define a breast tumor subtype that is estrogen receptor-positive and associated with a slow rate of tumor cell proliferation and a favorable prognosis for these cancer patients. RERG mRNA expression was induced rapidly in MCF-7 cells stimulated by beta-estradiol and repressed by tamoxifen treatment. Like Ras, RERG protein exhibited intrinsic GDP/GTP binding and GTP hydrolysis activity. Unlike Ras proteins, RERG lacks a known recognition signal for COOH-terminal prenylation and was localized primarily in the cytoplasm. Expression of RERG protein in MCF-7 breast carcinoma cells resulted in a significant inhibition of both anchorage-dependent and anchorage-independent growth in vitro and inhibited tumor formation in nude mice. These features of RERG are strikingly different from most Ras superfamily GTP-binding pro-teins and suggest that the loss of RERG expression may contribute to breast tumorigenesis.


Assuntos
Neoplasias da Mama/genética , Estrogênios/farmacologia , Proteínas de Ligação ao GTP/genética , Genes ras , Inibidores do Crescimento/genética , Células 3T3 , Sequência de Aminoácidos , Animais , Neoplasias da Mama/patologia , Feminino , GTP Fosfo-Hidrolases/metabolismo , Humanos , Camundongos , Dados de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Células Tumorais Cultivadas
15.
Cancer Res ; 61(12): 4701-6, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11406540

RESUMO

High amounts of nitric oxide (NO) produced by activated macrophages or NO donors are required to induce cytotoxicity and apoptosis in pathogens and tumor cells. High concentrations of NO may lead to nonspecific toxicity thereby limiting the use of NO donors in the treatment of cancer. In this study, we tested the possibility of potentiating the apoptotic action of NO in a human breast cancer cell line, MDA-MB-468, by combining it with a farnesyltransferase inhibitor (FTI), which has been shown to induce apoptosis in some other cancer cell lines with minimal toxicity to normal cells. DETA-NONOate, a long acting NO donor which has a half-life of 20 h at 37 degrees C, was used in this study. DETA-NONOate (1 mM), which releases NO in the range produced by activated macrophages, induced apoptosis after 36 h in MDA-MB-468 cells via cytochrome c release and caspase-9 and -3 activation. FTI (25 microM) potentiated the action of lower concentrations of DETA-NONOate (25-100 microM) by inducing apoptosis in these cells within 24 h by increasing cytochrome c release and caspase-9 and -3 activation. This effect was observed preferentially in the cancer cell lines studied with no apoptosis induction in normal breast epithelial cells. This novel combination of FTI and NO may emerge as a promising approach for the treatment of breast cancer.


Assuntos
Alquil e Aril Transferases/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Óxido Nítrico/farmacologia , Apoptose/fisiologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/enzimologia , Sinergismo Farmacológico , Inibidores Enzimáticos/farmacologia , Farnesiltranstransferase , Humanos , Óxido Nítrico/farmacocinética , Doadores de Óxido Nítrico/farmacocinética , Doadores de Óxido Nítrico/farmacologia , Compostos Nitrosos/farmacocinética , Compostos Nitrosos/farmacologia , Células Tumorais Cultivadas
16.
Oncogene ; 19(27): 3059-68, 2000 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-10871858

RESUMO

Farnesyltransferase inhibitor (FTI) induces apoptosis of transformed cells. This involves changes in mitochondria, including decrease of mitochondrial membrane potential and the release of cytochrome c. The released cytochrome c then induces events leading to the activation of caspase-3. In this study, we report that purine derivative cyclin-dependent kinase (Cdk) inhibitors, roscovitine and olomoucine, dramatically enhance this FTI-induced apoptosis of human cancer cell lines. We noticed the synergy between Cdk inhibitors and FTI through our screen to identify compounds that enhance FTI-induced apoptosis of promyelocytic leukemic cell line HL-60. The Cdk inhibitors by themselves do not induce apoptosis at the concentrations used. Roscovitine synergizes with FTI to release cytochrome c from mitochondria. In addition, we detected synergistic effects of FTI and roscovitine to inhibit hyperphosphorylation of retinoblastoma protein. Enhancement of FTI-induced apoptosis by roscovitine is not unique to HL-60 cells, since similar synergy was observed with a leukemic cell line CEM and a prostate cancer cell line LNCaP. In LNCaP cells, in addition to roscovitine and olomoucine, phophatidylinositol 3-kinase (PI 3-kinase) inhibitor, LY294002, was effective in enhancing FTI-induced apoptosis. However, the effects of roscovitine appear to be distinct from those of LY294002, since roscovitine did not affect Akt activity while LY294002 significantly decreased the activity of Akt. Our finding of the synergy between FTI and Cdk inhibitor is significant for understanding the mechanism of action of FTI as well as for clinical use of FTI.


Assuntos
Alquil e Aril Transferases/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Benzazepinas/farmacologia , Quinases Ciclina-Dependentes/antagonistas & inibidores , Purinas/farmacologia , Caspases/metabolismo , Linhagem Celular/efeitos dos fármacos , Cromonas/farmacologia , Grupo dos Citocromos c/metabolismo , Citosol/enzimologia , Sinergismo Farmacológico , Ativação Enzimática , Inibidores Enzimáticos , Farnesiltranstransferase , Células HL-60/efeitos dos fármacos , Humanos , Cinetina , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Morfolinas/farmacologia , Fosforilação/efeitos dos fármacos , Proteína do Retinoblastoma/metabolismo , Roscovitina
17.
18.
Biochim Biophys Acta ; 1166(1): 39-47, 1993 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-8431491

RESUMO

The intrinsic surface activity of a 36 kDa rabbit lung calcium-dependent phospholipid-binding protein (PLBP), a member of the annexin family of such proteins, at the air/water interface has been determined from measurements of surface tension of aqueous solutions, and surface concentration of 14C-labeled PLBP adsorbed from aqueous solution in the absence and presence of Ca2+. It was also possible to spread insoluble monolayers of PLBP to determine surface pressure vs. surface concentration isotherms, as well as surface elasticity and surface viscosity as a function of frequency from electrocapillary wave diffraction measurements. PLBP has been shown to exhibit significant intrinsic surface activity at the air/water interface, comparable to a variety of other hydrophobic proteins known to be quite surface active. In all cases, surface properties were enhanced by the presence of Ca2+, particularly the degree of surface viscoelasticity at close-packing in the monolayer. This is believed to reflect changes in protein conformation at the surface.


Assuntos
Anexinas/isolamento & purificação , Cálcio/química , Pulmão/química , Animais , Anexinas/química , Fenômenos Eletromagnéticos , Coelhos , Propriedades de Superfície , Tensão Superficial , Viscosidade
19.
J Med Primatol ; 19(6): 583-94, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2246778

RESUMO

A system to physically exercise rhesus monkeys is described, based on their natural capacity to climb. It is composed of an enclosure where a motor-driven rope is continually going down. The two stage training to this task is easily performed. The total work of each run, evaluated with the weight of the animal and the distance climbed, may be very stable. It was used to provide five sedentary monkeys with daily physical training for five months.


Assuntos
Macaca mulatta/fisiologia , Condicionamento Físico Animal , Animais , Comportamento Animal , Macaca mulatta/psicologia , Masculino , Esforço Físico , Reforço Psicológico
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