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1.
J Biol Chem ; 285(45): 34677-85, 2010 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-20736166

RESUMEN

Increased interferon (IFN)-ß signaling in patients with insufficient coronary collateralization and an inhibitory effect of IFNß on collateral artery growth in mice have been reported. The mechanisms of IFNß-induced inhibition of arteriogenesis are unknown. In stimulated monocytes from patients with chronic total coronary artery occlusion and decreased arteriogenic response, whole genome expression analysis showed increased expression of IFNß-regulated genes. Immunohistochemically, the IFNß receptor was localized in the vascular media of murine collateral arteries. Treatment of vascular smooth muscle cells (VSMC) with IFNß resulted in an attenuated proliferation, cell-cycle arrest, and increased expression of cyclin-dependent kinase inhibitor-1A (p21). The growth inhibitory effect of IFNß was attenuated by inhibition of p21 by RNA interference. IFNß-treated THP1 monocytes showed enhanced apoptosis. Subsequently, we tested if collateral artery growth can be stimulated by inhibition of IFNß-signaling. RNA interference of the IFNß receptor-1 (IFNAR1) increased VSMC proliferation, cell cycle progression, and reduced p21 gene expression. IFNß signaling and FAS and TRAIL expression were attenuated in monocytes from IFNAR1(-/-) mice, indicating reduced monocyte apoptosis. Hindlimb perfusion restoration 1 week after femoral artery ligation was improved in IFNAR1(-/-) mice compared with wild-type mice as assessed by infusion of fluorescent microspheres. These results demonstrate that IFNß inhibits collateral artery growth and VSMC proliferation through p21-dependent cell cycle arrest and induction of monocyte apoptosis. Inhibition of IFNß stimulates VSMC proliferation and collateral artery growth.


Asunto(s)
Ciclo Celular , Oclusión Coronaria/metabolismo , Interferón beta/antagonistas & inhibidores , Monocitos/metabolismo , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Neovascularización Fisiológica , Animales , Apoptosis/genética , Células Cultivadas , Oclusión Coronaria/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Femenino , Regulación de la Expresión Génica/genética , Humanos , Interferón beta/genética , Interferón beta/metabolismo , Masculino , Ratones , Ratones Noqueados , Interferencia de ARN , Receptor de Interferón alfa y beta/genética , Receptor de Interferón alfa y beta/metabolismo , Transducción de Señal/genética , Ligando Inductor de Apoptosis Relacionado con TNF/genética , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Receptor fas/genética , Receptor fas/metabolismo
2.
Clin Genet ; 77(4): 382-8, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20002460

RESUMEN

Most publications on the ethical aspects of genetic research into Alzheimer's Disease (AD) concentrate on the differences between the opinions of professionals and non-professionals. Differences in rating of morally relevant issues between groups of professionals have not yet been described. A modified Delphi study in two rounds was held to identify differences between groups of experts (i.e. clinicians, representatives of patient organisations, ethicists and persons with a commercial background). The strongest correlation was found between the opinions of ethicists and representatives of patient organisations (0.67) and between clinicians and ethicists (0.62). Moderate correlation (0.55) was found between the opinions of clinicians and representatives of patient organisations. Persons with a commercial background showed a weak correlation with clinicians (0.41), ethicists (0.35) and representatives of patient organisations (0.30). These differences in rating of morally relevant issues between various professional groups are relevant for clinical practice and dementia care, particularly the different rating of prenatal diagnosis found between clinicians and representatives of patient organisations. Interdisciplinary consultations between various professional groups -including at least researchers, clinicians and ethicists -are recommended to guarantee that all considerations will be incorporated into the debate on ethical issues of genetic research into AD.


Asunto(s)
Enfermedad de Alzheimer/genética , Técnica Delphi , Testimonio de Experto/ética , Investigación Genética/ética , Humanos , Países Bajos
3.
Neth Heart J ; 16(12): 436-9, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19127324

RESUMEN

During the last decennium, the role of bone marrow mononuclear cells (BMMC) has been underscored in the healing process after acute myocardial infarction (AMI). Although these cells improve left ventricular recovery after AMI in experimental studies, results from large-scale randomised trials investigating BMMC therapy in patients with AMI have shown contradictory results. To address this issue the HEBE study was designed, a multicentre, randomised trial, evaluating the effects of intracoronary infusion of BMMCs and the effects of intracoronary infusion of peripheral blood mononuclear cells after primary percutaneous coronary intervention. The primary endpoint of the HEBE trial is the change in regional myocardial function in dysfunctional segments at four months relative to baseline, based on segmental analysis as measured by magnetic resonance imaging. The results from the HEBE trial will provide detailed information about the effects of intracoronary BMMC therapy on post-infarct left ventricular recovery. In addition, further analysis of the data and material obtained may provide important mechanistic insights into the contribution of BMMCs to natural recovery from AMI as well as the response to cell therapy. This may significantly contribute to the development of improved cell-based therapies, aiming at optimising post-infarct recovery and preventing heart failure. (Neth Heart J 2008;16:436-9.).

4.
Artículo en Inglés | MEDLINE | ID: mdl-29321809

RESUMEN

BACKGROUND: In this study, two assumptions derived from the Good Lives Model were examined: whether subjective Quality of Life is related to delinquent behaviour and psychosocial problems, and whether adolescents with adequate coping skills are less likely to commit delinquent behaviour or show psychosocial problems. METHOD: To this end, data of 95 adolescents with severe psychiatric problems who participated in a four-wave longitudinal study were examined. Subjective Quality of Life was assessed with the ten domains of the Lancashire Quality of Life Profile and coping skills with the Utrecht Coping List for Adolescents. RESULTS: Results showed that adolescents who reported a lower Quality of Life on the health domain had more psychosocial problems at follow-up. No relationship was found between Quality of Life and delinquent behaviour. In addition, active and passive coping were associated with delinquent behaviour and psychosocial functioning at follow-up. CONCLUSIONS: Based on the results of this longitudinal study, the strongest support was found for the second assumption derived from the Good Lives Model. Adolescents with adequate coping skills are less likely to commit delinquent behaviour and have fewer psychosocial problems at follow-up. The current study provides support for the use of strength-based elements in the treatment programmes for adolescents in secure residential care.

5.
Br J Health Psychol ; 6(Pt 2): 103-20, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-14596728

RESUMEN

OBJECTIVES: This study investigated the association between delinquency and health in a sample of adolescents and young adults (aged 13-24) and examined whether the association could have been due to delinquency-related differences in demographic, socio-economic and life-style factors. METHOD: The study is based on cross-sectional data from a sample of 3677 adolescents and young adults interviewed as part of a survey of Dutch households. Health, health behaviour, and delinquency were assessed through self-report measures. RESULTS: Delinquency was significantly related to three of the four measures of health behaviour (smoking, alcohol consumption, and drug use), even after control for demographic and socio-economic factors. Delinquency was also significantly associated with all three measures of health assessed in this study (somatic symptoms, general health, and chronic conditions). However, only minimal support was found for the hypothesis that the association between delinquency and health was mediated by differences in health behaviour or demographic/socio-economic differences. CONCLUSIONS: Adolescent delinquents are less healthy than non-delinquents. Potential causes for this relationship are proposed. Possibly, personality factors, such as hostility, or psychosocial stress might explain why delinquency correlates with health.

6.
Vet Q ; 12(3): 183-92, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2219660

RESUMEN

(1) The efficacy of toltrazuril (Baycox) against coccidiosis was established on a broiler farm in an intermittent application during five consecutive growing periods. Treated birds were fed a broiler ration without anticoccidials. The efficacy of Baycox was compared with the nicarbazin-salinomycin shuttle. It was concluded that Baycox retarded the onset of Eimeria infection for several weeks. During the fifth rearing period coccidiosis problems emerged on the farm in all birds during medication, suggesting development of resistance. (2) During a laboratory experiment the efficacy of Baycox was studied in birds after inoculation with different numbers of oocysts at 7, 10 or 15 days of age. Baycox was applied at 10 and 11 days of age. In all cases medication with Baycox protected birds from coccidiosis during a period of at least 7 days. This effect of Baycox could be due to the long-existing tissue levels of the product and its metabolites as well as its specific effect on the second generation of schizonts. (3) In another laboratory experiment coccidia obtained from field trials were tested for sensitivity to Baycox in conjunction with two strains obtained from farms were coccidiosis emerged during application. The inoculation model developed in this study was used for sensitivity testing. One of the Eimeria strains tested was resistant to the product, one strain was tolerant and the remaining two strains, including the control strain, were fully sensitive to Baycox.


Asunto(s)
Pollos/parasitología , Coccidiosis/veterinaria , Coccidiostáticos/uso terapéutico , Enfermedades de las Aves de Corral/tratamiento farmacológico , Triazinas/uso terapéutico , Animales , Peso Corporal , Ciego/parasitología , Coccidiosis/tratamiento farmacológico , Coccidiostáticos/farmacología , Eimeria/efectos de los fármacos , Eimeria/aislamiento & purificación , Heces/parasitología , Masculino , Nicarbazina/uso terapéutico , Piranos/uso terapéutico , Triazinas/farmacología
7.
Minerva Cardioangiol ; 61(6): 617-25, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24253455

RESUMEN

Inadequate healing following acute myocardial infarction (AMI) can lead to the development of heart failure. The ischemic myocardium triggers an inflammatory response that clears cell debris and initiates the onset of scar tissue formation. The duration and intensity of this inflammatory response have been linked to the cardiac functioning post-AMI. In order to diminish scar tissue formation and stimulate regeneration of cardiac tissue, mesenchymal stem cell (MSC) have been applied post-AMI and showed beneficial effects on cardiac function. However, other than the expected regeneration of cardiac tissue, modulation of the inflammatory response post-AMI, especially related to an effect on monocytes/macrophages, was recently found to be an important aspect of MSC therapy. In healing post-AMI, monocytes and macrophages are key players that can either stimulate or repress inflammation using different phenotypes. Increased levels of the proinflammatory phenotype have clinically been associated with poor cardiac functional outcome post-AMI. MSC have been suggested to switch the monocytes/macrophages phenotype into a more anti-inflammatory state and might therefore beneficially influence the duration and intensity of the inflammatory response and subsequent cardiac function post-AMI. To gain more insight into this effect of MSC, this review provides an overview of the most relevant studies regarding this modulatory effect of MSC on monocytes/macrophages including its mechanisms to improve cardiac functioning post-AMI.


Asunto(s)
Inflamación/terapia , Trasplante de Células Madre Mesenquimatosas/métodos , Infarto del Miocardio/terapia , Animales , Cicatriz , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/prevención & control , Humanos , Inflamación/fisiopatología , Macrófagos/metabolismo , Células Madre Mesenquimatosas/metabolismo , Monocitos/metabolismo , Infarto del Miocardio/metabolismo , Infarto del Miocardio/fisiopatología , Fenotipo , Factores de Tiempo
8.
Heart ; 99(15): 1100-5, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23716567

RESUMEN

OBJECTIVE: Well-developed collaterals provide survival benefit in patients with obstructive coronary artery disease (CAD). Therefore, in this study we sought to determine which clinical variables are associated with arteriogenesis. DESIGN: Clinical and laboratory variables were collected before percutaneous coronary intervention. Multivariate analysis was performed to determine which variables are associated with the collateral flow index (CFI). PATIENTS: Data from 295 chronic total occlusion (CTO) patients (Bern, Switzerland, Amsterdam, the Netherlands and Jena, Germany) were pooled. In earlier studies, patients had varying degrees of stenosis. Therefore, different stages of development of the collaterals were used. In our study, a unique group of patients with CTO was analysed. INTERVENTIONS: Instead of angiography used earlier, we used a more accurate method to determine CFI using intracoronary pressure measurements. CFI was calculated from the occlusive pressure distal of the coronary lesion, the aortic pressure and central venous pressure. RESULTS: The mean CFI was 0.39 ± 0.14. After multivariate analysis, ß blockers, hypertension and angina pectoris duration were positively associated with CFI (B: correlation coefficient ß=0.07, SE=0.03, p=0.02, B=0.040, SE=0.02, p=0.042 and B=0.001, SE=0.000, p=0.02). Furthermore also after multivariate analysis, high serum leucocytes, prior myocardial infarction and high diastolic blood pressure were negatively associated with CFI (B=-0.01, SE=0.005, p=0.03, B=-0.04, SE=0.02, p=0.03 and B=-0.002, SE=0.001, p=0.011). CONCLUSIONS: In this unique cohort, high serum leucocytes and high diastolic blood pressure are associated with poorly developed collaterals. Interestingly, the use of ß blockers is associated with well-developed collaterals, shedding new light on the potential action mode of this drug in patients with CAD.


Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Circulación Colateral , Circulación Coronaria , Oclusión Coronaria , Hipertensión , Anciano , Presión Arterial , Presión Venosa Central , Estudios de Cohortes , Comorbilidad , Oclusión Coronaria/diagnóstico , Oclusión Coronaria/epidemiología , Oclusión Coronaria/fisiopatología , Oclusión Coronaria/terapia , Vasos Coronarios/fisiopatología , Técnicas de Diagnóstico Cardiovascular , Femenino , Alemania/epidemiología , Humanos , Hipertensión/complicaciones , Hipertensión/epidemiología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Países Bajos/epidemiología , Intervención Coronaria Percutánea/métodos , Atención Perioperativa/métodos , Atención Perioperativa/estadística & datos numéricos , Índice de Severidad de la Enfermedad , Estadística como Asunto , Suiza/epidemiología
9.
Vascul Pharmacol ; 56(5-6): 297-305, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22387744

RESUMEN

In this review we compare expression studies on monocyte subsets as an example to show the integrated possibilities of molecular databases and bioinformatic analysis tools. Monocytes have been recognized as cells with great plasticity and differentiation potential that play a pivotal role in revascularization processes, i.e. angiogenesis and arteriogenesis. To gain more insight in the relevant developmental programs, we compared the full-genome mRNA expression profiles of several distinct human monocyte subpopulations previously identified based on surface marker expression. These included classical and non-classical, M1 and M2 macrophages, circulating angiogenic cells (CAC), and non-monocyte-derived endothelial colony-forming cells (ECFC). Their transcriptional profiles revealed distinct and overlapping gene expression signatures and pathways reminiscent of utilization of transcription factors driving polarization into the different monocytic phenotypes. Hierarchical cluster analysis revealed that CAC are most related to M2 macrophages and unstimulated macrophages, and to a lesser extent to classical monocytes, and are quite distinct from M1 macrophages and ECFC. Analysis of the promoter region of CAC-expressed genes suggests that in particular the ETS family of transcription factors is important in CAC development. These analyses show the power of combining multiple datasets with existing databases on biological knowledge, to interpret full genome expression data.


Asunto(s)
Biología Computacional/métodos , Monocitos/metabolismo , Neovascularización Fisiológica/fisiología , Diferenciación Celular , Análisis por Conglomerados , Interpretación Estadística de Datos , Bases de Datos Factuales , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/fisiología , Genoma Humano , Humanos , Macrófagos/metabolismo
10.
Neth Heart J ; 20(3): 133-7, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22351557

RESUMEN

To reduce long-term morbidity after revascularised acute myocardial infarction, different therapeutic strategies have been investigated. Cell therapy with mononuclear cells from bone marrow (BMMC) or peripheral blood (PBMC) has been proposed to attenuate the adverse processes of remodelling and subsequent heart failure. Previous trials have suggested that cell therapy may facilitate arrhythmogenesis. In the present substudy of the HEBE cell therapy trial, we investigated whether intracoronary cell therapy alters the prevalence of ventricular arrhythmias after 1 month or the rate of severe arrhythmogenic events (SAE) in the first year. In 164 patients of the trial we measured function and infarct size with cardiovascular magnetic resonance (CMR) imaging. Holter registration was performed after 1 month from which the number of triplets (3 successive PVCs) and ventricular tachycardias (VT, ≥4 successive PVCs) was assessed. Thirty-three patients (20%) showed triplets and/or VTs, with similar distribution amongst the groups (triplets: control n = 8 vs. BMMC n = 9, p = 1.00; vs. PBMC n = 10, p = 0.67. VT: control n = 9 vs. BMMC n = 9, p = 0.80; vs. PBMC n = 11, p = 0.69). SAE occurred in 2 patients in the PBMC group and 1 patient in the control group. In conclusion, intracoronary cell therapy is not associated with an increase in ventricular arrhythmias or SAE.

13.
Eur J Surg Oncol ; 37(3): 252-7, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21215590

RESUMEN

AIM: Near-infrared (NIR) fluorescence optical imaging is a promising technique to assess the extent of colorectal metastases during curative-intended surgery. However, NIR fluorescence imaging of liver metastases is highly challenging due to hepatic uptake and clearance of many fluorescent dyes. In the current study, the biodistribution and the ability to demarcate liver and peritoneal metastases were assessed during surgery in a syngeneic rat model of colorectal cancer using an integrin α(v)ß(3)-directed NIR fluorescence probe. METHODS: Liver tumors and peritoneal metastases were induced in 7 male WAG/Rij rats by subcapsular inoculation of 0.5 × 10(6) CC531 colorectal cancer rat cells into three distinct liver lobes. Intraoperative and ex vivo fluorescence measurements were performed 24 (N = 3 rats, 7 tumors) and 48 h (N = 4 rats, 9 tumors) after intravenous administration of the integrin α(v)ß(3)-directed NIR fluorescence probe. RESULTS: Colorectal metastases had a minimal two-fold higher NIR fluorescence signal than healthy liver tissue and other abdominal organs (p < 0.001). The tumor-to-background ratio was independent of time of imaging (24 h vs. 48 h post-injection; p = 0.31), which facilitates flexible operation planning in future clinical applications. Total fluorescence intensity was significantly correlated with the size of metastases (R(2) = 0.92 for the 24 h group, R(2) = 0.96 for the 48 h group). CONCLUSION: These results demonstrate that colorectal intra-abdominal metastases can be clearly demarcated during surgery using an integrin α(v)ß(3) targeting NIR fluorescence probe. Translating these findings to the clinic will have an excellent potential to substantially improve the quality of cancer surgery.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/secundario , Integrina alfaVbeta3/metabolismo , Neoplasias Hepáticas/patología , Espectroscopía Infrarroja Corta/métodos , Animales , Modelos Animales de Enfermedad , Procesamiento de Imagen Asistido por Computador , Periodo Intraoperatorio , Masculino , Trasplante de Neoplasias , Ratas , Células Tumorales Cultivadas
14.
Clin Res Cardiol ; 98(11): 691-9, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19774327

RESUMEN

This summary article provides an update on novel clinical trials in the field of cardiovascular (CV) medicine which were presented at the annual meeting of the European Cardiac Society, held in Barcelona, Spain, in August-September 2009. The data were presented by leading experts in the field with relevant positions in the trials and registries. Unpublished reports should be considered as preliminary data as the analysis may change in the final publications. This article provides the reader with comprehensive summaries of the most recent diagnostic and therapeutic developments in CV medicine as previously reported (Kindermann et al. in Clin Res Cardiol 96:767-786, 2007; Müller et al. in Clin Res Cardiol 97:851-864, 2008).


Asunto(s)
Cardiología , Enfermedades Cardiovasculares/terapia , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/prevención & control , Ensayos Clínicos como Asunto , Humanos
15.
Avian Pathol ; 9(2): 143-53, 1980 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18770251

RESUMEN

Total alkaline phosphatase (ALP) activity in blood plasma of broilers suffering from infectious stunting after artificial infection was constantly higher than that of uninoculated control birds. While total ALP activity in blood plasma from inoculated broilers of various ages decreased after incubation at 56 degrees C, it increased in similarly treated plasma collected from broilers at 3, 21 and 28 days after inoculation. Investigations into the organ origin of the plasma ALP isoenzymes with agarose electrophoresis, column chromatography, L phenylalanine inhibition and heat treatment showed that the main part of ALP activity in blood plasma of both, inoculated and uninoculated birds was most likely of intestinal origin. In 3-day-old broilers no heat sensitive part of total ALP could be measured.

16.
Int J Clin Pract ; 56(9): 659-62, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12469979

RESUMEN

This study was conducted to compare the pharmacokinetic properties of the modified release 200 mg capsule of mebeverine and the plain 135 mg tablet of mebeverine after single and multiple doses in 12 healthy subjects in a randomised, crossover design. Single doses were given on days 1 and 7 and multiple doses (200 mg b.i.d. for the capsule and 135 mg t.i.d. for the tablet) on days 2-6 of the study. The 200 mg modified release capsule of mebeverine has extended release properties, as indicated by a lower Cmax, a later tmax and a longer elimination half-life than the plain tablet, while the bioavailability is optimal. No significant accumulation occurs after multiple doses of either formulation. The twice-daily dosage regimen of the 200 mg modified release capsule is a good alternative to the three times daily dosage regimen of the 135 mg plain tablet, because the reduced daily intake is likely to benefit patient compliance.


Asunto(s)
Parasimpatolíticos/farmacocinética , Fenetilaminas/farmacocinética , Adulto , Cápsulas , Estudios Cruzados , Preparaciones de Acción Retardada/administración & dosificación , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Masculino , Parasimpatolíticos/administración & dosificación , Cooperación del Paciente , Fenetilaminas/administración & dosificación , Comprimidos Recubiertos/administración & dosificación
17.
Bioorg Med Chem Lett ; 8(6): 663-8, 1998 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-9871579

RESUMEN

The synthesis and evaluation of PNA-(5')-DNA chimerae containing either a 5'-amide (i.e. 1a), a 5'-phosphodiester (i.e. 1b) or 5'-phosphonate linkages (i.e. 1c,d) at the junction site are described. The 5'-linkages could be installed using either 5'-amino-5'-deoxythymidine phosphoramidite 2, O-[2-(2-aminoethyl)-(thymin-1-ylacetyl)amino]ethyl phosphoramidite 3, N-(2-aminoethyl)-N-(thymin-1-ylacetyl)aminomethyl phosphonate 4 or N-(2-aminoethyl)-N-(allyloxycarbonyl)aminomethyl phosphonate 5 as building blocks, respectively. It is shown that PNA-(5')-DNA of type 1a-c have a higher binding affinity with complementary RNA than native DNA, and that the antisense activity is mainly due to RNase H.


Asunto(s)
ADN/metabolismo , Ácidos Nucleicos Heterodúplex/metabolismo , Ácidos Nucleicos de Péptidos/metabolismo , Quimera , ADN Complementario/metabolismo , Modelos Químicos , Hibridación de Ácido Nucleico/métodos , Oligonucleótidos Antisentido/síntesis química , ARN/metabolismo , Ribonucleasa H/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
18.
Antisense Nucleic Acid Drug Dev ; 8(2): 103-11, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9593048

RESUMEN

Antisense oligonucleotides (ONs) are designed to hybridize target mRNA in a sequence-specific manner and inhibit gene expression by preventing translation, either by activation of RNase H or steric blockage of the ribosome complex. Second-generation ONs, which possess greater binding affinity for target RNA relative to the isosequential phosphodiester (PO) ONs, have been developed and include, among others, peptide nucleic acids (PNA) and N3' P5' phosphoramidate oligonucleotides (npONs). In the present study, PNA and npON derivatives were targeted to the coding portion of the complementary mRNA of the N protein of the vesicular stomatitis virus (VSV) in order to evaluate their ability to arrest translation in an in vitro rabbit reticulocyte lysate system. High-affinity hybridization of ONs lacking RNase H activity was not sufficient to block translation in this test system. Only antisense ONs acting via an RNase H mechanism or by steric hindrance through covalent attachment (via transplatin modification) to the target mRNA were found to definitively arrest translation in this study.


Asunto(s)
Hibridación de Ácido Nucleico , Proteínas de la Nucleocápside , Nucleocápside/genética , Oligonucleótidos Antisentido/farmacología , Biosíntesis de Proteínas/efectos de los fármacos , ARN Mensajero/antagonistas & inhibidores , Ribonucleasa H/farmacología , Animales , Sistema Libre de Células , Células L , Sustancias Macromoleculares , Ratones , Estructura Molecular , Desnaturalización de Ácido Nucleico , ARN Mensajero/genética , Conejos , Reticulocitos/efectos de los fármacos , Reticulocitos/metabolismo , Ribosomas/fisiología , Relación Estructura-Actividad , Temperatura
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