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1.
Catheter Cardiovasc Interv ; 102(5): 823-833, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37668088

RESUMO

BACKGROUND: Severely calcified coronary lesions present a particular challenge for percutaneous coronary intervention. AIMS: The aim of this randomized study was to determine whether coronary intravascular lithotripsy (IVL) is non-inferior to rotational atherectomy (RA) regarding minimal stent area (MSA). METHODS: The randomized, prospective non-inferiority ROTA.shock trial enrolled 70 patients between July 2019 and November 2021. Patients were randomly (1:1) assigned to undergo either IVL or RA before percutaneous coronary intervention of severely calcified coronary lesions. Optical coherence tomography was performed at the end of the procedure for primary endpoint analysis. RESULTS: The primary endpoint MSA was lower but non-inferior after IVL (mean: 6.10 mm2 , 95% confidence interval [95% CI]: 5.32-6.87 mm2 ) versus RA (6.60 mm2 , 95% CI: 5.66-7.54 mm2 ; difference in MSA: -0.50 mm2 , 95% CI: -1.52-0.52 mm2 ; non-inferiority margin: -1.60 mm2 ). Stent expansion was similar (RA: 0.83 ± 0.10 vs. IVL: 0.82 ± 0.11; p = 0.79). There were no significant differences regarding contrast media consumption (RA: 183.1 ± 68.8 vs. IVL: 163.3 ± 55.0 mL; p = 0.47), radiation dose (RA: 7269 ± 11288 vs. IVL: 5010 ± 4140 cGy cm2 ; p = 0.68), and procedure time (RA: 79.5 ± 34.5 vs. IVL: 66.0 ± 19.4 min; p = 0.18). CONCLUSION: IVL is non-inferior regarding MSA and results in a similar stent expansion in a random comparison with RA. Procedure time, contrast volume, and dose-area product do not differ significantly.


Assuntos
Aterectomia Coronária , Doença da Artéria Coronariana , Litotripsia , Calcificação Vascular , Humanos , Aterectomia Coronária/efeitos adversos , Aterectomia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Constrição Patológica , Estudos Prospectivos , Angiografia Coronária/métodos , Resultado do Tratamento , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/terapia
2.
Anal Bioanal Chem ; 393(8): 1863-70, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19153722

RESUMO

The formation of Fe-Zn intermetallic compounds, as relevant in the commercial product galvannealed steel sheet, was investigated by scanning electron microscopy and different methods of X-ray diffraction. A scanning electron microscope with high resolution was applied to investigate the layers of the galvannealed coating and its topography. Grazing incidence X-ray diffraction (GID) was preferred over conventional Bragg-Brentano geometry for analysing thin crystalline layers because of its lower incidence angle alpha and its lower depth of information. Furthermore, in situ experiments at an environmental scanning electron microscope (ESEM) with an internal heating plate and at an X-ray diffractometer equipped with a high-temperature chamber were carried out. Thus, it was possible to investigate the phase evolution during heat treatment by X-ray diffraction and to display the growth of the zeta crystals in the ESEM.

3.
Vet Microbiol ; 131(3-4): 277-92, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18501535

RESUMO

The transcriptional responses of Pasteurella multocida to eight antibiotics with known mode of actions (MoAs) and one novel antibiotic compound with an unknown MoA were collected to create a compendium of transcriptional profiles for MoA studies. At minimal inhibitory concentration the three bactericidal compounds enrofloxacin, cefquinome and the novel compound had a minor impact on gene regulation with approximately 1% of the P. multocida genome affected, whilst the bacteriostatic compounds florfenicol, tilmicosin, rifampin, trimethoprim and brodimoprim regulated 20% of the genome. Novobiocin was special in that it regulated 40% of all P. multocida genes. Regulation of target genes was observed for novobiocin, rifampin, florfenicol and tilmicosin and signature genes were identified for most antibiotics. The transcriptional profile induced by the novel compound was unrelated to the compendium profiles suggesting a new MoA. The transcription of many P. multocida virulence factors, particularly genes involved in capsule synthesis and export, LPS synthesis, competence, adherence and iron transport were altered in the presence of antibiotics. Virulence gene transcription was mainly negatively affected, however the opposite effect was also observed in the case of rifampin where the up-regulation of the tad locus involved in tight adherence was seen. Novobiocin and trimethoprim caused a marked reduction in the transcription of capsule genes, which correlated with a concomitant reduction of the capsular layer on the surface of P. multocida. The broad negative impact on virulence gene transcription supports the notion that the therapeutic effect of some antibiotics could be a combination of growth and virulence inhibition.


Assuntos
Antibacterianos/farmacologia , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Pasteurella multocida/efeitos dos fármacos , Pasteurella multocida/patogenicidade , Transcrição Gênica/efeitos dos fármacos , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Análise por Conglomerados , Farmacorresistência Bacteriana Múltipla/genética , Pasteurella multocida/genética , Pasteurella multocida/metabolismo , Virulência
4.
Acta Neurobiol Exp (Wars) ; 76(1): 20-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27102915

RESUMO

Mitochondria have been suggested as a potential target for cytoprotective strategies. It has been shown that increased K+ uptake mediate by mitochondrial ATP-regulated potassium channels (mitoKATP channel) or large-conductance Ca2+-activated potassium channels (mitoBKCa channel) may provide protection in different models of cell death. Since recent findings demonstrated the presence of BKCa channels in neuronal mitochondria, the goal of the present study was to test the potential neuroprotective effects of BKCa channel modulators. Using organotypic hippocampal slice cultures exposed to glutamate, we demonstrated that preincubation of the slices with the BKCa channel opener NS1619 resulted in decreased neuronal cell death measured as reduced uptake of propidium iodide. This neuroprotective effect was reversed by preincubation with the BKCa channel inhibitors paxilline and Iberiotoxin (IbTx). Moreover, mitochondrial respiration measurements revealed that NS1619 induced an IbTx-sensitive increase in state 2 respiration of isolated brain mitochondria. In addition, electrophysiological patch-clamp studies confirmed the presence of BKCa channels in mitoplasts isolated from embryonic hippocampal cells. Taken together, our results confirm presence of BKCa channel in rat hippocampal neurons mitochondria and suggest putative role for mitoBKCa in neuroprotection.


Assuntos
Cálcio/metabolismo , Ácido Glutâmico/farmacologia , Hipocampo/efeitos dos fármacos , Canais de Potássio Ativados por Cálcio de Condutância Alta/fisiologia , Animais , Hipocampo/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neurônios/efeitos dos fármacos , Canais de Potássio/fisiologia , Ratos Wistar , Técnicas de Cultura de Tecidos
5.
Biochim Biophys Acta ; 1350(1): 65-74, 1997 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-9003459

RESUMO

A gene encoding a human liver carboxylesterase has been isolated and characterized. Analysis of three overlapping genomic lambda clones revealed that the gene spans about 30 kb and is made of 14 exons being 39 to 379 bp in length. The encoded protein is 550 amino acids long and is highly homologous to carboxylesterases of various mammalian species. The transcription start site was determined by 5'-RACE PCR. An additional 900 bp of DNA from the 5' flanking region of the gene was cloned and sequenced in order to elucidate the structure of the promoter. In this sequence several possible binding sites for transcription factors have been identified, but no TATA-box was present. When different parts of the putative promoter region were ligated in front of the luciferase gene and the constructs were transfected into CHO cells, the reporter gene was effectively transcribed, as demonstrated by the expression of enzyme activity.


Assuntos
Hidrolases de Éster Carboxílico/genética , Fígado/enzimologia , Regiões Promotoras Genéticas , Sequência de Aminoácidos , Animais , Sequência de Bases , Células CHO , Carboxilesterase , Hidrolases de Éster Carboxílico/biossíntese , Clonagem Molecular , Sequência Consenso , Cricetinae , Primers do DNA , Éxons , Feminino , Genes Reporter , Humanos , Íntrons , Luciferases/biossíntese , Dados de Sequência Molecular , Placenta/enzimologia , Reação em Cadeia da Polimerase , Gravidez , Splicing de RNA , Proteínas Recombinantes/biossíntese , Mapeamento por Restrição , Transfecção
6.
Genetics ; 142(2): 579-85, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8852855

RESUMO

Several retrotransposon fragments are integrated in the mitochondrial genome of Arabidopsis thaliana. These insertions are derived from all three classes of nuclear retrotransposons, the Ty1/copia-, Ty3/gypsy- and non-LTR/LINE-families. Members of the Ty3/gypsy group of elements have not yet been identified in the nuclear genome of Arabidopsis. The varying degrees of similarity with nuclear elements and the dispersed locations of the sequences in the mitochondrial genome suggest numerous independent transfer-insertion events in the evolutionary history of this plant mitochondrial genome. Overall, we estimate remnants of retrotransposons to cover > or = 5% of the mitochondrial genome in Arabidopsis.


Assuntos
Sequência Conservada , DNA Mitocondrial , DNA de Plantas , Retroelementos , Sequência de Aminoácidos , Arabidopsis/genética , Sequência de Bases , Dados de Sequência Molecular , Mutagênese Insercional
7.
Leukemia ; 13(8): 1227-34, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10450751

RESUMO

Dose escalation during consolidation therapy of de novo AML, including myeloablative chemotherapy supported with autologous peripheral blood stem cell transplantation (aPBSCT), continuously improved outcome. Therefore, quality control of transplants is getting increasing interest. We studied leukapheresis products (LPs), consecutively collected during postremission treatment of 20 patients with de novo AML for minimal residual disease (MRD) by 5-parametric flow cytometry and for myelodysplasia (MDS)-associated alterations by paired lineage-selected colony assays for colony-forming units-megakaryocytes (CFU-mega) and burst-granulocytes-monocytes colony-forming units (CFU) to evaluate the predictive value of these transplant-associated parameters on outcome. We defined the leukemia-associated immunophenotype at diagnosis and studied the impact of MRD detection in LPs collected after double induction with TAD (thioguanine, daunorubicin, cytarabine) and HAM (mitoxantrone, high-dose cytarabine, n=18 patients) and TAD consolidation treatment (n=20 patients) on outcome after aPBSCT. The level of MRD in the transplants correlated with the relapse-free survival (RFS) using a cut-off level of 1 x 10(-3) residual leukemic cells. The median RFS was 6 months for the group with > or = 1 x 10(-3) residual leukemic cells and has not been reached in the group with low MRD levels (< 1 x 10(-3)). By using the same cut-off level a weak correlation could also be demonstrated between MRD in the pregraft bone marrow and RFS (P = 0.04). Quantitatively abnormal megakaryocytic colony growth in the back-up LPs collected after double induction and in the transplant LPs was characterized by the ratio CFU-mega/CFU. In the group of relapsing patients the ratio CFU-mega/CFU was significantly lower than in the group of patients with CCR (P = 0.004), both in the back-ups and in the transplants. All patients with CFU-mega/CFU ratios < 0.12 relapsed, five of seven patients developed MDS before progressing to full leukemic relapse. Using the optimized cut-off level for the ratio CFU-mega/CFU (< vs > or = 0.12), seven of 10 relapsing patients (70%) could be identified to be at risk of relapse, whereas MRD in the transplants identified only 50% of the relapses and MRD in the pregraft bone marrow 25%. In conclusion, the study could identify two pretransplant risk factors predicting relapse in patients with AML receiving aPBSCT in first CR: MRD in transplants as well as MDS-like alterations within the transplants. These results may have multifold implications on the design of risk-adapted chemotherapy as well as on purging techniques and may contribute to a better understanding of leukemogenesis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/patologia , Leucemia Mieloide/terapia , Megacariócitos/patologia , Doença Aguda , Adolescente , Adulto , Terapia Combinada , Sobrevivência de Enxerto , Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/fisiologia , Humanos , Leucemia Mieloide/patologia , Leucemia Mieloide/fisiopatologia , Pessoa de Meia-Idade , Neoplasia Residual/patologia , Valor Preditivo dos Testes , Recidiva , Transplante Autólogo , Ensaio Tumoral de Célula-Tronco
8.
Eur J Cell Biol ; 78(10): 739-48, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10569246

RESUMO

Phagosome maturation is characterized by the sequential acquisition and loss of proteins by the phagocytic vacuole during the formation of an acidic and hydrolytic compartment where degradation of the phagocytosed particle occurs. Transfer of proteins to the maturing phagosome occurs by fusion with a range of vesicles. Here we describe direct fusion of early phagosomes with vesicles that appear to be derived from the biosynthetic pathway. In mouse bone marrow macrophages, the 51 kDa proform of cathepsin D was found in vesicles of the ER/Golgi network that could be discriminated from endosomal vesicles which in turn contained the 46 and 30 kDa processed forms of the enzyme. Procathepsin D was acquired by phagosomes formed around inert particles such as IgG-coated beads and could be "protected" by blocking acidification with Bafilomycin A1. Mycobacterium avium-containing vacuoles from established infections possessed both pro- and processed cathepsin D similar to early bead-containing phagosomes. In contrast phagosomes harboring dead mycobacteria demonstrated markedly enhanced acquisition of the 46kDa form within 4 h post internalization and only low levels of procathepsin D.


Assuntos
Catepsina D/metabolismo , Precursores Enzimáticos/metabolismo , Mycobacterium avium/patogenicidade , Fagossomos/enzimologia , Fagossomos/microbiologia , Sequência de Aminoácidos , Animais , Catepsina D/química , Precursores Enzimáticos/química , Técnicas In Vitro , Macrófagos/enzimologia , Macrófagos/microbiologia , Macrófagos/ultraestrutura , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Imunoeletrônica , Dados de Sequência Molecular , Peso Molecular , Mycobacterium avium/ultraestrutura , Fagossomos/ultraestrutura
9.
Eur J Cell Biol ; 80(1): 31-40, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11211933

RESUMO

Bacterial cell wall constituents are released from mycobacterial phagosomes and actively traffic within infected macrophages. Colocalization of fluorescently tagged bacterial moieties with endocytic tracers revealed the dynamic movement of released mycobacterial constituents into the endocytic network with accumulation in tubular lysosomal-like compartments. The released bacterial constituents not only penetrated the infected host cell but were also present in an extracellular microvesicular fraction. To identify the intracellular source of these exocytic compartments, released vesicular material was isolated from culture supernatants by differential ultracentrifugation and characterized by Western blot and electron microscopy analyses. The presence of lysosomal membrane proteins and lysosomal proteases suggested that labeled mycobacterial cell wall constituents access a constitutive lysosomal exocytic pathway. An abundance of multilamellar extracellular compartments morphologically reminiscent of MHC class II-enriched compartments (MIIC) implicated a MHC class II transport pathway in the extracellular release of bacterial constituents. Increases in intracellular free calcium have previously been shown to trigger lysosomal exocytosis by inducing fusion of lysosomes with the plasma membrane. To test if an increase in calcium would stimulate exocytosis with release of mycobacterial constituents, infected macrophages were exposed to the calcium ionophore A23187. The ionophore triggered the release of a microvesicular fraction containing labeled bacterial moieties, implicating calcium-regulated lysosomal exocytosis as a trafficking pathway by which mycobacterial products are released from infected macrophages.


Assuntos
Exocitose/imunologia , Macrófagos/microbiologia , Mycobacterium bovis/metabolismo , Animais , Cálcio/metabolismo , Parede Celular , Células Cultivadas , Endocitose/imunologia , Matriz Extracelular/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Líquido Intracelular/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium bovis/imunologia
10.
Biol Psychiatry ; 17(1): 49-59, 1982 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7059639

RESUMO

A quantitative method for the detection of DMPEA in urine was developed. It is based on the fluorometric determination of DMPEA in the form of its phosphopyridoxyl derivate. The limit of detection is 2 microgram DMPEA per 1 g creatinine. The DMPEA content was measured in urine from healthy persons, from schizophrenics, and from psychiatric patients without schizophrenia hospitalized with the schizophrenics. From each person five to ten 24-hr urine samples were investigated. DMPEA could be found neither in schizophrenics nor in controls or healthy persons. Finally, the urinary excretion of parenterally applied 14C-DMPEA was determined in three healthy volunteers and in three rats. In man about 25% of the label was excreted as DMPEA. The main metabolite in urine was homoveratric acid. Both compounds were excreted as conjugates.


Assuntos
Dimetoxifeniletilamina/urina , Fenetilaminas/urina , Esquizofrenia/urina , Biotransformação , Fluorometria , Humanos , Transtornos Mentais/urina
11.
Phytopathology ; 91(5): 511-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-18943596

RESUMO

ABSTRACT The importance of ethylene production for virulence of Pseudomonas syringae pvs. glycinea and phaseolicola was assayed by comparing bacterial multiplication and symptom development in bean and soybean plants inoculated with ethylene-negative (efe) mutants and wild-type strains. The efe mutants of Pseudomonas syringae pv. glycinea were significantly reduced in their ability to grow in planta. However, the degree of reduction was strain-dependent. Population sizes of efe mutant 16/83-E1 that did not produce the phototoxin coronatine were 10- and 15-fold lower than those of the wild-type strain on soybean and on bean, and 16/83-E1 produced very weak symptoms compared with the wild-type strain. The coronatine-producing efe mutant 7a/90-E1 reached fourfold and twofold lower population sizes compared with the wild-type strain on soybean and bean, respectively, and caused disease symptoms typical of the wild-type strain. Experiments with ethylene-insensitive soybeans confirmed these results. The virulence of the wild-type strains was reduced to the same extent in ethylene-insensitive soybean plants as the virulence of the efe mutants in ethylene-susceptible soybeans. In contrast, the virulence of Pseudomonas syringae pv. phaseolicola was not affected by disruption of the efe gene.

12.
Eur J Med Res ; 7(9): 415-6, 2002 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-12435620

RESUMO

Under antidepressive treatment with amitryptiline (100 mg/d) a 71-year old woman developed delirious symptoms, hyponatremia and a grand mal seizure followed by cardiovascular arrest. A few month later she ingested 48 mg reboxetine with suicidal intent. Overdosing of reboxetine, a selective noradrenaline re-uptake inhibitor, proceeded without complications.


Assuntos
Amitriptilina/efeitos adversos , Antidepressivos Tricíclicos/efeitos adversos , Antidepressivos/uso terapêutico , Morfolinas/uso terapêutico , Tentativa de Suicídio/psicologia , Idoso , Amitriptilina/uso terapêutico , Antidepressivos Tricíclicos/uso terapêutico , Feminino , Humanos , Reboxetina
13.
Acta Paediatr Suppl ; 407: 78-82, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7766966

RESUMO

In adolescents and adults with PKU, blood phenylalanine levels above 10 mg/dl are generally associated with white matter changes in MRI. The grade of these changes is correlated to most recent blood phenylalanine levels. Based on studies using T2 relaxometry the MRI changes seem to be the consequence of a reversible dysmyelination. The clinical relevance of these white matter changes remains unclear as the extent of MRI alterations did not correlate with IQ, neurological and electrophysiological deficits of the patients. The intracerebral phenylalanine concentration as measured by protonspectroscopy amounts to about 50% of blood phenylalanine concentrations. Preliminary data indicate that brain phenylalanine levels remain constant if blood concentrations exceed 20 mg/dl. This might be of clinical relevance for the treatment of adolescent and adult PKU patients.


Assuntos
Encefalopatias/patologia , Doenças Desmielinizantes/patologia , Imageamento por Ressonância Magnética , Fenilcetonúrias/complicações , Química Encefálica , Encefalopatias/etiologia , Estudos de Casos e Controles , Doenças Desmielinizantes/etiologia , Eletrofisiologia , Humanos , Fenilalanina/análise , Fenilcetonúrias/sangue , Fenilcetonúrias/dietoterapia
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