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1.
Strahlenther Onkol ; 190(2): 186-91, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24362502

RESUMO

PURPOSE: To retrospectively analyze treatment outcomes after particle therapy using protons or carbon ions for mucosal melanoma of the head and neck (HNMM) at the Hyogo Ion Beam Medical Center, as well as to compare proton therapy (PT) and carbon ion therapy (CIT). PATIENTS AND METHODS: Data from 62 HNMM patients without metastasis, treated with PT or CIT between October 2003 and April 2011 were analyzed. Median patient age was 70.5 years (range 33-89 years). Of the total patients, 33 (53 %) had received PT and 29 (47 %) had undergone CIT. Protocols for 65 or 70.2 GyE in 26 fractions were used for both ion types. RESULTS: Median follow-up was 18.0 months (range 5.2-82.7 months). The 1-/2-year overall survival (OS) and local control (LC) rates were 93 %/61 % and 93 %/78 % for all patients, 91 %/44 % and 92 %/71 % for the PT patients and 96 %/62 % and 95 %/59 % for the CIT patients, respectively. No significant differences were observed between PT and CIT. Local recurrence was observed in 8 patients (PT: 5, CIT: 3) and 29 (PT: 18, CIT: 11) experienced distant metastases. Acute reactions were acceptable and all patients completed the planned radiotherapy. Regarding late toxicity, grade 3 or greater events were observed in 5 patients (PT: 3, CIT: 2), but no significant difference was observed between PT and CIT. CONCLUSION: Our single-institution retrospective analysis demonstrated that particle therapy for HNMM achieved good LC, but OS was unsatisfactory. There were no significant differences between PT and CIT in terms of either efficacy or toxicity.


Assuntos
Radioterapia com Íons Pesados/métodos , Melanoma/radioterapia , Neoplasias Otorrinolaringológicas/radioterapia , Terapia com Prótons/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Intervalo Livre de Doença , Fracionamento da Dose de Radiação , Feminino , Seguimentos , Humanos , Masculino , Melanoma/mortalidade , Melanoma/patologia , Pessoa de Meia-Idade , Neoplasias Bucais/mortalidade , Neoplasias Bucais/patologia , Neoplasias Bucais/radioterapia , Recidiva Local de Neoplasia/etiologia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Neoplasias Nasais/mortalidade , Neoplasias Nasais/patologia , Neoplasias Nasais/radioterapia , Neoplasias Otorrinolaringológicas/mortalidade , Neoplasias Otorrinolaringológicas/patologia , Neoplasias dos Seios Paranasais/mortalidade , Neoplasias dos Seios Paranasais/patologia , Neoplasias dos Seios Paranasais/radioterapia , Lesões por Radiação/etiologia , Estudos Retrospectivos
2.
Phys Rev Lett ; 112(3): 034802, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24484144

RESUMO

A novel scheme for the focusing of high-energy leptons in future linear colliders was proposed in 2001 [P. Raimondi and A. Seryi, Phys. Rev. Lett. 86, 3779 (2001)]. This scheme has many advantageous properties over previously studied focusing schemes, including being significantly shorter for a given energy and having a significantly better energy bandwidth. Experimental results from the ATF2 accelerator at KEK are presented that validate the operating principle of such a scheme by demonstrating the demagnification of a 1.3 GeV electron beam down to below 65 nm in height using an energy-scaled version of the compact focusing optics designed for the ILC collider.

3.
Rev Sci Instrum ; 91(2): 023321, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32113432

RESUMO

The Linear IFMIF (International Fusion Materials Irradiation Facility) Prototype Accelerator (LIPAc) is aiming at demonstrating the low energy section of a 40 MeV/125 mA IFMIF deuteron accelerator up to 9 MeV with a full beam current in cw operation. For such a high-power beam, the LIPAc injector is required to produce a 100 keV D+ beam with 140 mA and match it for injection into the Radio Frequency Quadrupole (RFQ) accelerator. The injector is designed by CEA-Saclay based on the high intensity light ion source (SILHI). In 2019, the commissioning of the RFQ to demonstrate the D+ beam acceleration at a low duty cycle (0.1%) was conducted. A nominal beam current of 125 mA D+ beam was accelerated up to 5 MeV through the RFQ successfully. The LIPAc injector fully satisfied the requirements for RFQ beam commissioning at the pulse mode.

4.
Oncogene ; 26(3): 449-55, 2007 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-16832346

RESUMO

Normal human diploid fibroblasts (HDFs) are refractory to oncogene-mediated transformations in vitro, compared with rodent fibroblasts. As successful oncogene-mediated transformations of normal HDFs have been reported using the human telomerase catalytic subunit, it has been considered that telomerase activity contributes to the species-specific transformability. However, these transformed HDFs are much less malignant compared with those of rodent cells, suggesting the existence of undefined mechanisms that render HDFs resistant to malignant transformation. Here, cDNA microarray analysis identified caveolin-1 as one of the possible cellular factors involved in such mechanisms. The mitogen-activated protein kinases (MAPK) pathway downregulates Caveolin-1 in rodent fibroblasts, transformed by coexpression of the SV40 early region and activated H-Ras. In contrast, the coexpression of these two oncogenes in HDFs failed to reduce the expression level of Caveolin-1. These results strongly suggest the presence of critical differences in events following the phosphorylation of ERK during the activation process of the MAPK signaling pathway between human and rodent cells, as the ERK protein was similarly phosphorylated in both systems. Furthermore, the small interfering RNA-mediated suppression of Caveolin-1 facilitated the oncogene-mediated transformation of normal HDFs, clearly indicating that the differences in the transformability between human and rodent cells are due, at least in part, to the mechanism responsible for the resistance to Ras-induced Caveolin-1 downregulation in HDFs.


Assuntos
Caveolina 1/metabolismo , Transformação Celular Neoplásica , Fibroblastos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas ras/metabolismo , Animais , Caveolina 1/antagonistas & inibidores , Caveolina 1/genética , Regulação para Baixo , Fibroblastos/citologia , Regulação da Expressão Gênica , Humanos , Luciferases/metabolismo , Pulmão/metabolismo , Camundongos , Células NIH 3T3 , Fosforilação , RNA Interferente Pequeno/farmacologia , Ratos , Transdução de Sinais , Transfecção , Proteínas ras/genética
5.
Br J Cancer ; 99(5): 781-8, 2008 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-18682709

RESUMO

Thyroid carcinoma cells often do not express thyroid-specific genes including sodium iodide symporter (NIS), thyroperoxidase (TPO), thyroglobulin (TG), and thyrotropin-stimulating hormone receptor (TSHR). Treatment of thyroid carcinoma cells (four papillary and two anaplastic cell lines) with histone deacetylase inhibitors (SAHA or VPA) modestly induced the expression of the NIS gene. The promoter regions of the thyroid-specific genes contained binding sites for hepatocyte nuclear factor 3 beta (HNF3 beta)/forkhead box A2 (FoxA2), thyroid transcription factor 1 (TTF-1), and CCAAT/enhancer binding protein (C/EBP beta). Quantitative reverse transcription-polymerase chain reaction (RT-PCR) showed decreased expression of HNF3 beta/FoxA2 and TTF-1 mRNA in papillary thyroid carcinoma cell lines, when compared with normal thyroid cells. Forced expression of these genes in papillary thyroid carcinoma cells inhibited their growth. Furthermore, the CpG island in the promoter region of HNF3 beta/FoxA2 was aberrantly methylated; and treatment with 5-aza-2-deoxycytidine (5-Az) induced its expression. Immunohistochemical staining showed that C/EBP beta was localised in the nucleus in normal thyroid cells but was detected in the cytoplasm in papillary thyroid carcinoma cells. Subcellular fractionation of papillary thyroid carcinoma cell lines also demonstrated high levels of expression of C/EBP beta in the cytoplasm, suggesting that a large proportion of C/EBP beta protein is inappropriately localised in the cytoplasm. In summary, these findings reveal novel abnormalities in thyroid carcinoma cells.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Fator 3-beta Nuclear de Hepatócito/fisiologia , Proteínas Nucleares/fisiologia , Simportadores/genética , Neoplasias da Glândula Tireoide/genética , Fatores de Transcrição/fisiologia , Sequência de Bases , Proteína beta Intensificadora de Ligação a CCAAT/genética , Linhagem Celular Tumoral , Metilação de DNA , Primers do DNA , Fator 3-beta Nuclear de Hepatócito/genética , Humanos , Imuno-Histoquímica , Proteínas Nucleares/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias da Glândula Tireoide/patologia , Fator Nuclear 1 de Tireoide , Fatores de Transcrição/genética
6.
J Microsc ; 231(Pt 1): 21-7, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18638186

RESUMO

We evaluated the preservation of ultra-structure and immunoreactivity in cryosections of central nervous system tissue mounted with and stored in a sucrose-gelatin solution for one month at -20 degrees C or -80 degrees C. The ultra-structure of synaptic structure in these sections was well preserved and comparable to that of freshly cut cryosections. Quantitative analysis of mitochondrial ultra-structure demonstrated gradually lower degrees of preservation in sections stored at -20 degrees C and -80 degrees C compared with that in freshly cut sections. We observed distinct metabotropic glutamate receptor 1 (mGluR1)-immunogold labelling at peri-synaptic sites in freshly cut sections and also in those stored at -20 degrees C and -80 degrees C. Quantitative analysis of mGluR1 immunoreactivity revealed that the total number of immunogold particles per synapse and the number of non-specifically bound particles were similar under all three conditions. However, the percentage of gold particles bound to a specific synaptic region was greatest in freshly cut sections (79.0%) and progressively lower in sections stored at -20 degrees C (76.1%), in which sections were not frozen, and in sections stored at -80 degrees C (68.0%). These data indicate that ultra-thin cryosections may be conveniently stored in a sucrose-gelatin solution at -20 degrees C for cryoultramicrotomy-immunolabelling.


Assuntos
Córtex Cerebelar/ultraestrutura , Criopreservação/métodos , Crioultramicrotomia/métodos , Congelamento , Animais , Córtex Cerebelar/imunologia , Gelatina , Imuno-Histoquímica , Masculino , Ratos , Ratos Sprague-Dawley , Receptores de Glutamato/metabolismo , Soluções , Sacarose
7.
Phys Med Biol ; 51(7): 1919-28, 2006 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-16552114

RESUMO

In the absence of a predictor of beam output in proton therapy using a broad beam, the beam output is obtained for individual treatments by calibrating the beam monitors. The calibration is carried out under conditions similar to the treatment conditions but with a phantom instead of the patient. However, the dose in the phantom a priori differs from that in the patient. In order to deliver the accurate dose, a correction factor has been introduced to correct the difference. This correction factor is referred to as a scatter factor in an analogy with photon therapy, and is defined as the ratio of the dose at the prescription point in the patient to the dose at the calibration point in the phantom. Under the calibration conditions at Hyogo Ion Beam Medical Center (HIBMC), the range compensator and the collimator, which are usually required in proton therapy with a broad beam, are not used. Therefore the scatter factor includes the effects of the devices as well as the difference between the dose in the patient and that in the phantom. We have developed an estimator using a dose calculation based on the pencil beam algorithm and implemented it in a treatment planning system (TPS) for clinical use. This estimator estimates the scatter factor by calculating the ratio of the doses under the same conditions in the TPS. In order to evaluate the performance of the estimator, demonstrations were carried out for cases with measurable outcomes using a gantry nozzle at HIBMC. We observed 2-3% differences between the measurements and the estimations. These differences were considered to result from the limitations of the dose calculation algorithm in modelling the beam and the patient.


Assuntos
Imagens de Fantasmas , Fótons , Planejamento da Radioterapia Assistida por Computador , Humanos , Espalhamento de Radiação , Água/química
8.
Sci Rep ; 6: 36569, 2016 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-27857146

RESUMO

We report and discuss high-flux generation of circularly polarized γ-rays by means of Compton scattering. The γ-ray beam results from the collision of an external-cavity-enhanced infrared laser beam and a low emittance relativistic electron beam. By operating a non-planar bow-tie high-finesse optical Fabry-Perot cavity coupled to a storage ring, we have recorded a flux of up to (3.5 ± 0.3) × 108 photons per second with a mean measured energy of 24 MeV. The γ-ray flux has been sustained for several hours. In particular, we were able to measure a record value of up to 400 γ-rays per collision in a full bandwidth. Moreover, the impact of Compton scattering on the electron beam dynamics could be observed resulting in a reduction of the electron beam lifetime correlated to the laser power stored in the Fabry-Perot cavity. We demonstrate that the electron beam lifetime provides an independent and consistent determination of the γ-ray flux. Furthermore, a reduction of the γ-ray flux due to intrabeam scattering has clearly been identified. These results, obtained on an accelerator test facility, warrant potential scaling and revealed both expected and yet unobserved effects. They set the baseline for further scaling of the future Compton sources under development around the world.

9.
Oncogene ; 12(8): 1645-52, 1996 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-8622884

RESUMO

To understand how the growth of T-cells transformed by Human T-cell leukemia virus type I (HTLV-I) is deregulated, we analysed the expression of cell-cycle regulatory genes in HTLV-I infected and non-infected T-cell lines. We investigated the gene for 6 cyclins, 4 cyclin-dependent kinases, and 5 cyclin-dependent kinase inhibitors, and found the following: (1) HTLV-I infected T-cell lines preferentially expressed cyclin D2, whereas cyclin D3 was the major D-type cyclin in HTLV-I negative T-cell lines; (2) HTLV-I infected T-cell lines expressed strikingly low levels of p18Ink4 compared with those that were HTLV-I negative; (3) HTLV-I infected T-cell lines expressed high levels of p21Waf1/Cip1/Sdi1, whereas p21Waf1/Cip1/Sdi1 was undetectable in HTLV-I negative T-cell lines. These features were also found in T-cells immortalized by Tax1, which we established. Therefore, it is strongly suggested that Tax1 alters the expression of these cell-cycle regulatory genes.


Assuntos
Ciclo Celular/genética , Quinases Ciclina-Dependentes/genética , Ciclinas/biossíntese , Regulação Neoplásica da Expressão Gênica , Produtos do Gene tax/genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Leucemia de Células T/genética , Leucemia de Células T/virologia , Proteínas de Transporte/biossíntese , Linhagem Celular Transformada , Ciclina D2 , Inibidor p16 de Quinase Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p21 , Quinases Ciclina-Dependentes/antagonistas & inibidores , Ciclinas/genética , Humanos , Leucemia de Células T/patologia , Células Tumorais Cultivadas/virologia
10.
Oncogene ; 13(2): 399-405, 1996 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-8710379

RESUMO

The Cdk6 protein level rapidly decreased after treatment with the tyrosine kinase inhibitor herbimycin A in human T-cell lines. This decrease is fairly specific, because the level of other Cdks such as Cdk2 and Cdk4 and cyclins such as cyclin D2, cyclin E and cyclin A, did not change significantly even after 24 h treatment with herbimycin A. Pulse-chase analysis revealed that the decrease in the Cdk6 protein level results from reduced stability of the protein. Our results suggest that herbimycin A-sensitive protein tyrosine kinase(s) are involved in the regulation of the Cdk6 protein level.


Assuntos
Quinases Ciclina-Dependentes , Inibidores Enzimáticos/farmacologia , Proteínas Serina-Treonina Quinases/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Quinonas/farmacologia , Linfócitos T/enzimologia , Animais , Benzoquinonas , Northern Blotting , Linhagem Celular , Quinase 6 Dependente de Ciclina , Ciclinas/metabolismo , Estabilidade Enzimática , Fase G1/efeitos dos fármacos , Humanos , Lactamas Macrocíclicas , Camundongos , RNA Mensageiro/metabolismo , Rifabutina/análogos & derivados , Linfócitos T/efeitos dos fármacos
11.
Oncogene ; 14(17): 2071-8, 1997 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-9160887

RESUMO

Tax1, a transcriptional trans-activator of the Human T-cell leukemia virus type I (HTLV-I), induces the expression of many cellular genes through interaction with at least three distinct cellular transcription factors; CREB/ATF, NF-kappaB, and SRF. This Tax1-induced activation of cellular genes is considered to be a critical event in T-cell transformation by HTLV-I. To elucidate the role of each Tax1-inducible transcriptional pathway in T-cell transformation, we introduced Tax1 mutants with different trans-activating phenotypes into peripheral blood lymphocytes (PBL) by retroviral vectors. Analysis of these PBLs revealed that activation of the NF-kappaB pathway is sufficient to promote the growth response to IL-2. However, for the clonal expansion of CD4+ T-cells, which is a characteristic result of HTLV-I infection, activation of the CREB/ATF and SRF pathways is also required.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/fisiologia , Proteínas de Ligação a DNA/fisiologia , Regulação Viral da Expressão Gênica , Produtos do Gene tax/fisiologia , Genes pX , Vírus Linfotrópico T Tipo 1 Humano/genética , NF-kappa B/fisiologia , Proteínas Nucleares/fisiologia , Linfócitos T/virologia , Ativação Transcricional , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Divisão Celular/efeitos dos fármacos , Células Clonais , Produtos do Gene tax/genética , Humanos , Interleucina-2/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Fenótipo , Mutação Puntual , Fator de Resposta Sérica , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo
12.
Oncogene ; 18(42): 5785-94, 1999 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-10523859

RESUMO

The t(11;18) (q21;q21) translocation is a characteristic chromosomal aberration in low-grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) type. We previously identified a YAC clone y789F3, which includes the breakpoint at 18q21 in a MALT lymphoma patient. BAC and PAC contigs were constructed on the YAC, and BAC 193f9 was found to encompass the breakpoint region. In the present study, we further narrowed down the breakpoint region at 18q21 in five MALT lymphoma patients by means of FISH and Southern blot analyses using the plasmid contig constructed from BAC 193f9. The breakpoints at 18q21 in three of the five MALT lymphoma patients were found to be clustered approximately within the 20 kb region. By using exon amplification and cDNA library screening, we identified a novel cDNA spanning the breakpoint region that exhibited aberrant mRNA signals in four of the five MALT lymphoma patients. The nucleotide sequence predicted an 813 amino acid protein that shows significant sequence similarity to the CD22beta and laminin 5 alpha3b subunit. We refer to the gene encoding this transcript as MALT1 (Mucosa-Associated Lymphoid Tissue lymphoma translocation gene 1). The alteration of MALT1 by translocation strongly suggests that this gene plays an important role in the pathogenesis of MALT lymphoma.


Assuntos
Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 18/genética , Linfoma de Zona Marginal Tipo Células B/genética , Proteínas de Neoplasias/genética , Translocação Genética/genética , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Southern Blotting , Caspases , Neoplasias do Colo/genética , Mapeamento de Sequências Contíguas , Feminino , Humanos , Hibridização in Situ Fluorescente , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa , Proteínas de Neoplasias/isolamento & purificação , Plasmídeos/genética
13.
Biochim Biophys Acta ; 1229(2): 149-54, 1995 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-7727495

RESUMO

The structural factors of antimycin A molecule required for inhibitory action were studied using newly synthesized antimycin A derivatives with bovine heart submitochondrial particles, in order to probe the interaction between antimycin A and its binding site. In particular, we focused upon the roles of the amide bond bridge, which connects the salicylic acid and dilactone ring moieties, and the 3-formylamino group in the salicylic acid moiety. The lack of formation of an intramolecular hydrogen-bond between phenolic OH and amide carbonyl groups resulted in a remarkable loss of the activity (by four orders of magnitude), indicating that this hydrogen-bond is essential for the inhibition. This result suggested that both the phenolic OH and the carbonyl groups form a hydrogen-bond with some residues at a fixed conformation. In addition, the inhibitory potency was remarkably decreased by N-methylation of the amide bond moiety, indicating that the NH group might function in hydrogen-bond interaction with the binding site. The N-methylation of 3-formylamino group also resulted in a decrease in the activity, probably due to a loss of the rotational freedom of this functional group. Molecular orbital calculation studies with respect to the conformation of the 3-formylamino group indicated that this group takes an active conformation when the formyl carbonyl projects to the opposite side of the phenolic OH group. Based upon a series of structure-activity studies of synthetic antimycin A analogues, we propose a tentative model for antimycin A binding in its binding cavity.


Assuntos
Antimicina A/metabolismo , Amidas/química , Aminas/química , Animais , Antimicina A/análogos & derivados , Antimicina A/química , Sítios de Ligação , Bovinos , Ligação de Hidrogênio , Relação Estrutura-Atividade
14.
Biochim Biophys Acta ; 1365(3): 443-52, 1998 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-9711297

RESUMO

The annonaceous acetogenins are the most potent of the known inhibitors of bovine heart mitochondrial complex I. These inhibitors act, at the terminal electron transfer step of the enzyme, in a similar way to the usual complex I inhibitors, such as piericidin A and rotenone; however, structural similarities are not apparent between the acetogenins and these known complex I inhibitors. A systematic set of isolated natural acetogenins was prepared and examined for their inhibitory actions with bovine heart mitochondrial complex I to identify the essential structural factors of these inhibitors for the exhibition of potent activity. Despite their very potent activity, the structural requirements of the acetogenins are not particularly rigid and remain somewhat ambiguous. The most common structural units, such as adjacent bis-tetrahydrofuran (THF) rings and hydroxyl groups in the 4- and/or 10-positions, were not essential for exhibiting potent activity. The stereochemistry surrounding the THF rings, surprisingly, seemed to be unimportant, which was corroborated by an exhaustive conformational space search analysis, indicating that the model compounds, with different stereochemical arrangements around the THF moieties, were in fairly good superimposition. Proper length and flexibility of the alkyl spacer moiety, which links the THF and the alpha, beta-unsaturated gamma-lactone ring moieties, were essential for the potent activity. This probably results from some sort of specific conformation of the spacer moiety which regulates the two ring moieties to locate into an optimal spatial position on the enzyme. It is, therefore, suggested that the structural specificity of the acetogenins, required for optimum inhibition, differs significantly from that of the common complex I inhibitors in which essential structural units are compactly arranged and conveniently defined. The structure-activity profile for complex I inhibition is discussed in comparison with those for other biological activities.


Assuntos
Furanos/química , Furanos/farmacologia , Lactonas/química , Lactonas/farmacologia , NAD(P)H Desidrogenase (Quinona)/antagonistas & inibidores , Animais , Bovinos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Cinética , Mitocôndrias Cardíacas/enzimologia , Modelos Moleculares , Conformação Molecular , Plantas/química , Estereoisomerismo , Relação Estrutura-Atividade
15.
Circulation ; 103(5): 664-9, 2001 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-11156877

RESUMO

BACKGROUND: The aim of the present study was to investigate the feasibility and potential value of the computer-controlled, 3D, echocardiographic reconstruction of the color Doppler-imaged vena contracta (CDVC) and the flow convergence (FC) region as a means of accurately and quantitatively estimating the severity of a ventricular septal defect (VSD). METHODS AND RESULTS: We performed a 3D reconstruction of the CDVC and the FC region in 19 patients with an isolated VSD using an ultrasound system interfaced with a Tomtec computer. The variable asymmetric geometry of the CDVC and the FC region could be 3D-visualized in all patients. The 3D-measured areas of CDVC correlated well with volumetric measurements of the severity of VSD (r=0.97, P:<0.001). Regression analysis between the shunt flow rate (calculated from the product of the area of CDVC and the continuous Doppler-derived velocity time integral) and the corresponding reference results (calculated by cardiac catheterization) demonstrated a close correlation (r=0.95, P:<0.001). There was also a good correlation between shunt flow rates calculated using the conventional 2D, 1-axis measurement of the FC isovelocity surface area with the hemispheric assumption (r=0.95, P:<0.001); shunt flow rates calculated using 3D, 3-axis measurements of the FC region (r=0.97, P:<0.01); and reference results by cardiac catheterization. However, the 2D method substantially underestimated the actual shunt flow rate. CONCLUSIONS: The 3D reconstruction of the CDVC and the FC region may aid in quantifying the severity of VSD.


Assuntos
Ecocardiografia Doppler em Cores/métodos , Comunicação Interventricular/diagnóstico , Criança , Pré-Escolar , Ecocardiografia Tridimensional , Estudos de Viabilidade , Humanos , Processamento de Imagem Assistida por Computador , Lactente , Estudos Prospectivos , Fluxo Sanguíneo Regional , Índice de Gravidade de Doença
16.
Cell Death Differ ; 11(2): 208-16, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14605674

RESUMO

Omi/HtrA2 is a mitochondrial serine protease that is released into the cytosol during apoptosis and promotes cytochrome c (Cyt c)dependent caspase activation by neutralizing inhibitor of apoptosis proteins (IAPs) via its IAP-binding motif. The protease activity of Omi/HtrA2 also contributes to the progression of both apoptosis and caspase-independent cell death. In this study, we found that wild-type Omi/HtrA2 is more effective at caspase activation than a catalytically inactive mutant of Omi/HtrA2 in response to apoptotic stimuli, such as UV irradiation or tumor necrosis factor. Although similar levels of Omi/HtrA2 expression, XIAP-binding activity, and Omi/HtrA2 mitochondrial release were observed among cells transfected with catalytically inactive and wild-type Omi/HtrA2 protein, XIAP protein expression after UV irradiation was significantly reduced in cells transfected with wild-type Omi/HtrA2. Recombinant Omi/HtrA2 was observed to catalytically cleave IAPs and to inactivate XIAP in vitro, suggesting that the protease activity of Omi/HtrA2 might be responsible for its IAP-inhibiting activity. Extramitochondrial expression of Omi/HtrA2 indirectly induced permeabilization of the outer mitochondrial membrane and subsequent Cyt c-dependent caspase activation in HeLa cells. These results indicate that protease activity of Omi/HtrA2 promotes caspase activation through multiple pathways.


Assuntos
Caspases/metabolismo , Mitocôndrias/enzimologia , Serina Endopeptidases/metabolismo , Transdução de Sinais , Apoptose , Catálise , Complexo de Ataque à Membrana do Sistema Complemento , Proteínas do Sistema Complemento , Citocromos c/metabolismo , Retroalimentação Fisiológica , Regulação da Expressão Gênica , Glicoproteínas/genética , Glicoproteínas/metabolismo , Células HeLa , Serina Peptidase 2 de Requerimento de Alta Temperatura A , Humanos , Membranas Intracelulares/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais , Mutação/genética , Proteínas/metabolismo , Serina Endopeptidases/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X
17.
J Am Coll Cardiol ; 22(4): 1182-8, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8409058

RESUMO

OBJECTIVES: The purpose of this study was to determine whether wall motion abnormalities are present before or after the Fontan procedure in patients with a univentricular heart of the left ventricular type with an absent right atrioventricular valve connection (tricuspid atresia) and to assess the impact of such abnormalities on ventricular performance and clinical outcome. BACKGROUND: Normal systolic and diastolic ventricular function is critical for a successful Fontan repair. However, there have been no previous studies addressing the relation between regional ventricular function and hemodynamic factors. METHODS: Thirty-seven pediatric patients were studied with biplane ventricular cineangiography. There were 20 male and 17 female patients whose mean age at the time of the Fontan operation was 6.5 +/- 3.5 years (range 2.5 to 15.6). Eighteen patients were studied preoperatively, 25 at > 1 year postoperatively and 6 serially. Wall motion was assessed by a centerline method. Normal ranges for wall motion and other variables were established from 25 normal subjects. RESULTS: Wall motion abnormalities were observed in 2 of 18 patients preoperatively and in 11 of 25 patients postoperatively. Age at operation and ventricular volumes did not differ between postoperative patients who had normal (group I, 14 patients) or abnormal (group II, 11 patients) wall motion. However, ventricular mass and the mass/volume ratio were significantly greater and systolic variables and cardiac index were significantly lower in group II versus group I. Two patients in group I were considered to have a clinically poor outcome (persistent heart failure), and five in group II had heart failure, including one who died late. CONCLUSIONS: These observations suggest that postoperative regional wall motion abnormalities in this setting are not rare, may be related to excessive hypertrophy and may contribute to cardiac dysfunction and a poor clinical outcome.


Assuntos
Cardiomegalia/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Contração Miocárdica , Complicações Pós-Operatórias/fisiopatologia , Valva Tricúspide/anormalidades , Valva Tricúspide/cirurgia , Adolescente , Cateterismo Cardíaco , Procedimentos Cirúrgicos Cardíacos/métodos , Cardiomegalia/diagnóstico , Cardiomegalia/diagnóstico por imagem , Estudos de Casos e Controles , Criança , Pré-Escolar , Cineangiografia , Diástole , Eletrocardiografia , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/diagnóstico por imagem , Ventrículos do Coração , Humanos , Masculino , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/diagnóstico por imagem , Prognóstico , Volume Sistólico , Sístole , Resultado do Tratamento , Resistência Vascular
18.
J Am Coll Cardiol ; 26(1): 272-6, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7797762

RESUMO

OBJECTIVES: This study aimed to 1) compare in vitro intravascular ultrasound images of human pulmonary arteries with corresponding histologic sections, and 2) correlate the relation between intravascular ultrasound findings and Heath-Edwards pathologic grade of pulmonary vascular changes. BACKGROUND: The pathologic assessment of the pulmonary vascular bed is essential for diagnosis and management of congenital heart disease with pulmonary hypertension. METHODS: We evaluated and compared intravascular ultrasound images with histologic findings at identical sites in 40 pulmonary artery segments from 17 autopsy studies: group 1 = 7 patients with pulmonary hypertension (Heath-Edwards grade I to V, 20 segments); group 2 = 10 patients without cardiopulmonary disease (20 segments). RESULTS: In group 2, the pulmonary artery wall echo consisted of a single layer. In group 1, 1) all segments of pulmonary arteries from patients with pulmonary hypertension showed a three-layered appearance; 2) in patients with mild pulmonary hypertension (Heath-Edwards grades I and II), intravascular ultrasound demonstrated increased thickness of the echoluscent zone due to medial hypertrophy with no intimal reaction; 3) patients with severe pulmonary hypertension (Health-Edwards grade III or higher) had intravascular ultrasound findings of increased medial thickness and a bright inner layer from intimal hyperplasia; 4) percent wall thickness derived from intravascular ultrasound showed a significant correlation with that determined by histologic examination (r = 0.89, p = 0.0001, n = 20). CONCLUSIONS: Changes observed with intravascular ultrasound imaging correlate well with histopathologic grade. Thus, intravascular ultrasound may have significant utility in the evaluation of pulmonary vascular morphology in patients with pulmonary hypertension.


Assuntos
Cardiopatias Congênitas/diagnóstico por imagem , Hipertensão Pulmonar/diagnóstico por imagem , Artéria Pulmonar/diagnóstico por imagem , Ultrassonografia de Intervenção , Adolescente , Adulto , Cadáver , Criança , Pré-Escolar , Feminino , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/patologia , Humanos , Hipertensão Pulmonar/complicações , Hipertensão Pulmonar/patologia , Técnicas In Vitro , Lactente , Recém-Nascido , Masculino , Artéria Pulmonar/patologia
19.
J Am Coll Cardiol ; 31(5): 1074-80, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9562009

RESUMO

OBJECTIVES: This study sought to assess the endothelial function of long-term coronary artery lesions in patients with Kawasaki disease (KD). BACKGROUND: The vascular function of the coronary arteries in children with long-term KD remains uncertain. We report our findings of the vascular response of the coronary arteries to intracoronary injection of acetylcholine (ACh) in patients with KD. METHODS: A total of 35 patients (25 patients with KD and 10 control subjects) were examined using coronary angiography. Individual arteries were divided into four groups according to the type of the coronary artery lesion: group 1 consisted of 25 sites with regressed aneurysms. These aneurysms had developed in the acute stage but had subsequently regressed and demonstrated normal findings on the follow-up coronary angiogram. Group 2 consisted of 24 sites with persistent aneurysms. Group 3 involved 60 angiographically normal sites in the same patients as those in group 1 or 2. Group 4 consisted of 30 sites in control subjects who had congenital heart disease with normal coronary arteries. During coronary angiography we infused 15 microg of ACh chloride into the coronary artery. The lumen diameters were measured using a cine videodensitometric analyzer to study the distensibility of the coronary artery wall. RESULTS: The mean (+/-SD) change in diameter was an increase of 11.71+/-12.34% in group 3 (coronary arteries without lesions in patients with KD) and 12.21+/-9.71% in the control group, demonstrating marked vasodilation in both groups. In contrast, the changes in the regressed aneurysms of group 1 and in the persistent aneurysms of group 2 were -2.65+/-12.12% and -0.08+/-6.51%, respectively, demonstrating no change or mild vasoconstriction. The change in groups 1 and 2 was significantly less than that in group 3 or in the control group. Group 3 showed no significant difference from the control group. CONCLUSIONS: These findings suggest that long-term coronary artery lesions, even after aneurysm regression, may have impaired endothelial function. A long-term follow-up study for those patients is essential.


Assuntos
Acetilcolina , Vasos Coronários/fisiopatologia , Endotélio Vascular/fisiopatologia , Síndrome de Linfonodos Mucocutâneos/fisiopatologia , Acetilcolina/administração & dosagem , Adolescente , Angiografia Coronária , Vasos Coronários/efeitos dos fármacos , Feminino , Humanos , Injeções Intra-Arteriais , Masculino , Síndrome de Linfonodos Mucocutâneos/diagnóstico por imagem , Vasodilatação
20.
J Am Coll Cardiol ; 20(4): 920-6, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1527303

RESUMO

OBJECTIVES: This study was designed to evaluate changes in ventricular volume, mass and cardiac function before and after creation of an atrial to pulmonary connection in patients with a univentricular atrioventricular connection. BACKGROUND: Intact systolic and diastolic performance is critical for successful establishment of an atrial dependent circulation, and few studies are available comparing cardiac performance before and after creation. METHODS: With the use of radionuclide blood pool imaging and ventricular cineangiography, 54 patients (mean age 6.4 +/- 3.4 years) were studied. Twenty-eight patients were investigated preoperatively and 36 greater than 1 year after repair and compared with a control population. RESULTS: Before operation, end-diastolic volume and wall mass were significantly increased compared with those of control subjects; however, the mass/volume ratio was normal (1.08 +/- 0.31 g/ml for the preoperative group; 0.97 +/- 0.19 for control subjects). Although end-diastolic volume returned to normal after the procedure, wall mass remained elevated and contributed to an elevated mass/volume ratio (1.20 +/- 0.38 g/ml). After the procedure, systemic vascular resistance index was significantly elevated compared with that before surgery or with that of control subjects (1,199 +/- 373, 2,120 +/- 645, 1,556 +/- 275 dynes.s.cm-5.m2: pre- and postrepair and control subjects, respectively). Radionuclide studies demonstrated that preoperative ejection fraction (52 +/- 9, 50 +/- 9, 60 +/- 8%), peak ejection (2.58 +/- 0.66, 2.95 +/- 0.81, 3.73 +/- 0.70 EDV/s) and peak filling rates (2.84 +/- 0.75, 2.75 +/- 0.79, 3.84 +/- 0.51 end-diastolic volumes [EDV/s]) were significantly reduced compared with those of control subjects and remained so after surgery. CONCLUSIONS: These data suggest that systolic and diastolic function is depressed preoperatively in these patients, remains unchanged after the creation of an atrial-dependent circulation and is associated with an increased systemic vascular resistance. Long-term issues addressing preservation of cardiac function need to be prospectively studied.


Assuntos
Átrios do Coração/cirurgia , Cardiopatias Congênitas/fisiopatologia , Cardiopatias Congênitas/cirurgia , Contração Miocárdica/fisiologia , Artéria Pulmonar/cirurgia , Função Ventricular/fisiologia , Criança , Cineangiografia , Feminino , Imagem do Acúmulo Cardíaco de Comporta , Coração/diagnóstico por imagem , Cardiopatias Congênitas/diagnóstico , Ventrículos do Coração/anormalidades , Humanos , Masculino , Resistência Vascular/fisiologia
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