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1.
J Intern Med ; 279(6): 576-91, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26940242

RESUMEN

BACKGROUND: In the field of Alzheimer's disease (AD), the validation of biomarkers for early AD diagnosis and for use as a surrogate outcome in AD clinical trials is of considerable research interest. OBJECTIVE: To characterize the clinical profile and genetic, neuroimaging and neurophysiological biomarkers of prodromal AD in amnestic mild cognitive impairment (aMCI) patients enrolled in the IMI WP5 PharmaCog (also referred to as the European ADNI study). METHODS: A total of 147 aMCI patients were enrolled in 13 European memory clinics. Patients underwent clinical and neuropsychological evaluation, magnetic resonance imaging (MRI), electroencephalography (EEG) and lumbar puncture to assess the levels of amyloid ß peptide 1-42 (Aß42), tau and p-tau, and blood samples were collected. Genetic (APOE), neuroimaging (3T morphometry and diffusion MRI) and EEG (with resting-state and auditory oddball event-related potential (AO-ERP) paradigm) biomarkers were evaluated. RESULTS: Prodromal AD was found in 55 aMCI patients defined by low Aß42 in the cerebrospinal fluid (Aß positive). Compared to the aMCI group with high Aß42 levels (Aß negative), Aß positive patients showed poorer visual (P = 0.001), spatial recognition (P < 0.0005) and working (P = 0.024) memory, as well as a higher frequency of APOE4 (P < 0.0005), lower hippocampal volume (P = 0.04), reduced thickness of the parietal cortex (P < 0.009) and structural connectivity of the corpus callosum (P < 0.05), higher amplitude of delta rhythms at rest (P = 0.03) and lower amplitude of posterior cingulate sources of AO-ERP (P = 0.03). CONCLUSION: These results suggest that, in aMCI patients, prodromal AD is characterized by a distinctive cognitive profile and genetic, neuroimaging and neurophysiological biomarkers. Longitudinal assessment will help to identify the role of these biomarkers in AD progression.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/líquido cefalorraquídeo , Apolipoproteínas E/genética , Biomarcadores/líquido cefalorraquídeo , Encéfalo/diagnóstico por imagen , Electroencefalografía , Femenino , Genotipo , Humanos , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Fragmentos de Péptidos/líquido cefalorraquídeo , Punción Espinal , Proteínas tau/líquido cefalorraquídeo
2.
Clin Nutr ; 32(3): 338-45, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23123043

RESUMEN

BACKGROUND & AIMS: In cancer patients, metabolic alterations, reduced immune competence and anti-cancer treatment can increase the risk of infections. A rapid-acting nutritional intervention might reduce this risk and support overall treatment. The present study investigated whether one week of intervention with a specific medical food led to fatty acid incorporation and functional immunological changes. METHODS: In a randomized, double-blind study, 38 cancer patients receiving radiotherapy consumed daily for one week 400 ml of specific medical food, which is high in protein and leucine, and enriched with fish oil and specific oligosaccharides (Active group), or iso-caloric/iso-nitrogenous product (Control group). Blood samples were taken at day 0 (baseline) and day 7. RESULTS: After one week of intervention, the incorporation of EPA and DHA in white blood cells was significantly higher in the Active group (2.6% and 2.6% of total fatty acids) compared to the Control group (1.0% and 2.2% of total fatty acids) (p < 0.001 and p < 0.05). Serum PGE2 levels decreased in the Active group and increased in the Control group (p < 0.01). No differences were observed on cytokine production in LPS-stimulated whole blood cultures. CONCLUSIONS: In cancer patients receiving radiotherapy, nutritional intervention with a specific medical food rapidly increased the percentage EPA and DHA in white blood cell phospholipids and reduced serum levels of the inflammatory mediator PGE2 within one week. CLINICAL REGISTRATION NUMBER: NTR2121.


Asunto(s)
Dinoprostona/sangre , Ácidos Docosahexaenoicos/farmacocinética , Ácido Eicosapentaenoico/farmacocinética , Neoplasias/radioterapia , Anciano , Biomarcadores/sangre , Método Doble Ciego , Femenino , Aceites de Pescado/administración & dosificación , Alimentos Fortificados/análisis , Humanos , Interferón gamma/sangre , Interleucina-10/sangre , Interleucina-1beta/sangre , Interleucina-8/sangre , Leucina/administración & dosificación , Leucocitos/química , Masculino , Persona de Mediana Edad , Oligosacáridos/administración & dosificación , Fosfolípidos/sangre , Factor de Necrosis Tumoral alfa/sangre
3.
Nervenarzt ; 83(5): 661-73, 2012 May.
Artículo en Alemán | MEDLINE | ID: mdl-22576052

RESUMEN

Due to the demographic developments, diagnosis and treatment, dementia constitutes an increasing medical challenge and is likely to have an increasing socioeconomic impact. Dementia does not reflect a single disease but encompasses a variety of underlying conditions, heterogeneous clinical courses and therapeutic approaches, among which Alzheimer's disease represents the most common cause. Therefore, a thorough differential diagnosis of dementia is of major importance. To date the current diagnosis of dementia according to ICD-10/DMS-IV is based on clinical criteria. In addition, the concept of mild cognitive impairment comprises early cognitive dysfunction without clinically apparent dementia. Alzheimer's disease is more and more conceptualized as a disease continuum with mild cognitive impairment as an early and manifest dementia as the later stage of the disease. This review gives an overview on the current diagnostic approaches and the proposed revisions of diagnostic and research criteria for Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/diagnóstico , Demencia/complicaciones , Demencia/diagnóstico , Humanos
4.
Ann Oncol ; 23(4): 1030-6, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21693769

RESUMEN

BACKGROUND: EndoTAG-1 (ET), a novel formulation of cationic liposomes carrying embedded paclitaxel (Taxol), shows antitumoral activity, targeting tumor endothelial cells in solid tumors. Patients with advanced metastatic cancer were evaluated investigating effects on pharmacokinetics and tumor vasculature using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and contrast-enhanced ultrasound (CEUS). PATIENTS AND METHODS: The pharmacokinetic (PK) profile of ET (22 mg/m(2) i.v.) was evaluated after single and repeated doses. DCE-MRI and CEUS explored hepatic metastases before, during and after the 4-week treatment cycle. Angiogenic biomarkers were assessed. Tumor response was evaluated by modified RECIST. RESULTS: The PK profile demonstrated slight accumulation of paclitaxel after repeated doses. DCE-MRI parameters K(trans) and/or iAUC(60) showed a trend to decrease. Changes of blood flow-dependent parameters of DCE-MRI and CEUS were well correlated. Angiogenic biomarkers revealed no clear trend. ET was generally well tolerated; common toxic effects were fatigue and hypersensitivity reactions. Nine (9 of 18) patients had stable disease after the first treatment cycle. Four patients without disease progression continued treatment. CONCLUSIONS: This study including multiple pretreated patients with different metastatic cancer revealed individually distinctive hemodynamic alterations by DCE-MRI. The PK profiles of ET were similar as observed previously.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Neoplasias de la Mama/patología , Neoplasias Colorrectales/patología , Neoplasias Hepáticas/secundario , Paclitaxel/uso terapéutico , Neoplasias Pancreáticas/patología , Adulto , Anciano , Inhibidores de la Angiogénesis/farmacocinética , Inhibidores de la Angiogénesis/farmacología , Angiotensina II/sangre , Área Bajo la Curva , Neoplasias de la Mama/sangre , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias Colorrectales/irrigación sanguínea , Neoplasias Colorrectales/tratamiento farmacológico , Medios de Contraste , Endotelina-1/sangre , Femenino , Humanos , Interleucinas/sangre , Liposomas , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/tratamiento farmacológico , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Paclitaxel/farmacocinética , Paclitaxel/farmacología , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/tratamiento farmacológico , Ultrasonografía , Factor A de Crecimiento Endotelial Vascular/sangre
5.
Chem Commun (Camb) ; 46(25): 4535-7, 2010 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-20454728

RESUMEN

A significant enhancement of the intensity of the room temperature photoluminescence in the visible region by two orders of magnitude is observed upon introducing oxygen containing functional groups into well-defined oligosilane dendrimers.


Asunto(s)
Dendrímeros/química , Nanoestructuras/química , Oxígeno/química , Silanos/química , Silicio/química , Modelos Moleculares
6.
J Clin Pharm Ther ; 32(2): 197-8, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17381670

RESUMEN

Hyperprolactinemia is a frequent side-effect in the use of atypical antipsychotics. The propensity to induce hyperprolactinemia is highly substance dependent and hyperprolactinemia is not always associated with clinical side-effects. We report a case in which hyperprolactinemia and amenorrhea under the treatment with olanzapine gets normalized after the addition of aripiprazole.


Asunto(s)
Amenorrea/inducido químicamente , Hiperprolactinemia/inducido químicamente , Piperazinas/efectos adversos , Quinolonas/efectos adversos , Adulto , Amenorrea/diagnóstico , Antipsicóticos/efectos adversos , Antipsicóticos/uso terapéutico , Aripiprazol , Benzodiazepinas/efectos adversos , Benzodiazepinas/uso terapéutico , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/psicología , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Interacciones Farmacológicas , Quimioterapia Combinada , Femenino , Humanos , Hiperprolactinemia/diagnóstico , Olanzapina , Piperazinas/uso terapéutico , Quinolonas/uso terapéutico
7.
Pharmacopsychiatry ; 39(1): 39-40, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16453254

RESUMEN

Massive elevations of serum creatine kinase (CK) can occur in a significant number of patients treated with neuroleptics in the absence of neuroleptic malignant syndrome (NMS). We report two cases of CK-elevations associated with quetiapine treatment, which disappeared after drug discontinuation. To our knowledge, case number one is the first case of quetiapine-induced CK elevation in a neuroleptic-naïve patient. We thus suggest CK assessment when myalgia occurs with neuroleptic treatment.


Asunto(s)
Antipsicóticos/efectos adversos , Creatina Quinasa/sangre , Dibenzotiazepinas/efectos adversos , Adulto , Anciano , Antipsicóticos/uso terapéutico , Benzodiazepinas/uso terapéutico , Clozapina/uso terapéutico , Trastorno Depresivo Mayor/sangre , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/enzimología , Dibenzotiazepinas/uso terapéutico , Humanos , Masculino , Mianserina/análogos & derivados , Mianserina/uso terapéutico , Mirtazapina , Olanzapina , Dolor/etiología , Trastornos Psicóticos/sangre , Trastornos Psicóticos/tratamiento farmacológico , Fumarato de Quetiapina
8.
Anticancer Res ; 21(4A): 2341-50, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11724291

RESUMEN

BACKGROUND: In previous studies we isolated a new cDNA fragment named C13 which is down-regulated in malignant prostate tissues. The corresponding gene is localized on chromosome 13q13 between the known tumour suppressor genes (TSG) BRCA-2 and RB-1. MATERIALS AND METHODS: Loss of heterozygosity (LOH) analyses were carried out in the region of C13 in order to investigate the importance of the new putative TSG for prostate cancer development. Using semiquantitative LOH analysis, we screened 21 prostate carcinoma patients of different tumour stages (pT2-pT4) for 14 microsatellite markers in the region of C13 (13q13) and in the flanking BRCA-2 and the RB-1 loci. RESULTS: For 18 (86%) patients LOH or allelic imbalances were found. We identified three to nine alterations in affected tumours per marker. An overall genetic alteration frequency per patient of 38% (86 of 225 informative cases) could be calculated. One important finding regarding the overall frequency of determined microsatellite instability is that the LOH/AI rate of 47% for the seven C13-associated markers was higher than for the four markers of the RB-1 locus (39%) and for the three BRCA-2 markers (25%). Surprisingly, defining LOH critical regions (LCR) for the investigated marker panel, eight of the ten affected LCR cases showed chromosomal imbalances simultaneously for the RB-1 and the C13 LOH markers. CONCLUSIONS: The high LOH rate for eight different microsatellite markers in and around the putative TSG locus C13 on chromosome 13q13 further supports an involvement of C13 in prostate tumourigenesis.


Asunto(s)
Cromosomas Humanos Par 13/genética , Pérdida de Heterocigocidad , Neoplasias de la Próstata/genética , Anciano , Desequilibrio Alélico , Mapeo Cromosómico , ADN de Neoplasias/genética , Genes BRCA2 , Genes de Retinoblastoma/genética , Humanos , Masculino , Repeticiones de Microsatélite/genética , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/patología
9.
Nucleic Acids Res ; 29(13): 2706-14, 2001 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-11433015

RESUMEN

The RNA polymerase II (pol II) transcription complex undergoes a structural transition around registers 20-25, as indicated by ExoIII footprinting analyses. We have employed a highly purified system to prepare pol II complexes stalled at very precise positions during the initial stage of transcript elongation. Using potassium permanganate we analyzed the open region ('transcription bubble') of complexes stalled between registers 15 and 35. We found that from register 15 up to 25 the transcription bubble expands concomitantly with RNA synthesis. At registers 26 and 27 the bubble has a high tendency to retract at the leading edge. Addition of transcription elongation factor TFIIS re-extends the bubble to the stall site, resulting in complexes competent for transcript elongation. These findings are discussed in the light of the recently determined structures for RNA polymerases.


Asunto(s)
ADN/química , ADN/metabolismo , Conformación de Ácido Nucleico , ARN Polimerasa II/metabolismo , Factores Generales de Transcripción , Factores de Transcripción TFII , Transcripción Genética/genética , Factores de Elongación Transcripcional , Animales , Secuencia de Bases , Bovinos , ADN/genética , Huella de ADN , Proteínas de Unión al ADN/metabolismo , Guanosina Trifosfato/análogos & derivados , Guanosina Trifosfato/metabolismo , Guanosina Trifosfato/farmacología , Células HeLa , Humanos , Sustancias Macromoleculares , Mutación/genética , Permanganato de Potasio , Subunidades de Proteína , ARN Polimerasa II/química , ARN Mensajero/análisis , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Proteína de Unión a TATA-Box , Moldes Genéticos , Factor de Transcripción TFIIB , Factor de Transcripción TFIIH , Factores de Transcripción/metabolismo , Transcripción Genética/efectos de los fármacos
10.
Int J Oncol ; 19(1): 25-30, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11408918

RESUMEN

Telomerase, a ribonucleoprotein complex is activated in the vast majority of human malignancies, including prostate cancer. Its inhibition is a putative way to affect cancer proliferation and might be used in the therapy of tumors. We analysed the influence of antisense phosphorothioate oligonucleotides (PTO) against the reverse transcriptase subunit of telomerase on prostate cancer cell viability, telomerase activity and telomere length. DU145 prostate cancer cells were cultivated in PTO containing medium. The PTO-incorporation was confirmed by confocal laser scanning microscopy. Cell viability was measured by a WST-1 tetrazolium assay. After 15 days of antisense PTO treatment, a significant inhibition of cell viability occurred. Telomerase activity was determined by a telomeric repeat amplification protocol (TRAP) assay and telomere length by Southern blot analysis. Since the long-term telomerase antisense treatment reduces the viability of prostate cancer cells significantly, this antisense approach could be a new therapeutic strategy to treat patients with advanced prostate cancer.


Asunto(s)
Oligonucleótidos Antisentido/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , ARN , Telomerasa/genética , Células Tumorales Cultivadas/efectos de los fármacos , Southern Blotting , Muerte Celular , Supervivencia Celular/efectos de los fármacos , Proteínas de Unión al ADN , Regulación hacia Abajo , Humanos , Masculino , Microscopía Confocal , Microscopía de Contraste de Fase , Neoplasias de la Próstata/enzimología , Neoplasias de la Próstata/patología , Telomerasa/metabolismo , Telómero/química , Telómero/metabolismo , Tionucleótidos/uso terapéutico , Células Tumorales Cultivadas/enzimología , Células Tumorales Cultivadas/patología
11.
Urologe A ; 40(3): 207-16, 2001 May.
Artículo en Alemán | MEDLINE | ID: mdl-11405130

RESUMEN

Although local prostate cancer (PC) can be cured in most cases by radical prostatectomy, therapies for metastatic and androgen-independent PC are limited and rather unsatisfactory. Gene and immunotherapy based on progress in molecular biology are novel treatment options especially for these PC stages. In the field of passive immunotherapy, chimeric/recombinant antibodies and derivatives thereof show promising results in early clinical trails (phase I/II). Before treatment, a careful selection of patients who could profit from this therapy is important (theranostics). Concerning active immunotherapy, administration of dendritic cells loaded with PC-specific tumor antigens seems to be an interesting therapy option. Promising gene therapeutic approaches include antisense and suicide gene therapy. Antisense therapy studies revealed the advantage that even systemic treatment does not lead to strong toxic side effects if the target gene is not involved in important cell functions. Improvement of the gene therapy vectors and identification of new therapeutic genes for PC are essential prerequisites for successful application in humans. Present developments of alternative approaches show that future treatments will be very patient specific.


Asunto(s)
Terapia Genética , Inmunización Pasiva , Inmunoterapia Activa , Neoplasias de la Próstata/terapia , Ensayos Clínicos como Asunto , Humanos , Masculino , Estadificación de Neoplasias , Evaluación de Procesos y Resultados en Atención de Salud , Neoplasias de la Próstata/patología
12.
Prostate ; 47(2): 91-101, 2001 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-11340631

RESUMEN

METHODS AND RESULTS: By differential display we isolated a new cDNA-fragment, named C13, that is downregulated in malignant prostate tissues. Northern hybridization revealed the fragment to be part of 3.0 and 4.4 kb mRNAs. Fluorescence in situ hybridization, Southern blotting and radiation hybrid mapping demonstrated a chromosomal localization of C13 on 13q12-14 closest to the SHGC-34125 marker. In the 5% chromosomal environment of C13 we detected changes of the allelic status in 13 of 21 prostate cancers. A downregulation was detected at the mRNA level in patients with advanced carcinoma. The 3.0 kb full length cDNA clone encodes a protein with an open reading frame of 2,202 bp or 733 amino acids. The corresponding protein contains a putative nuclear localization signal, several glutamine clusters and an alpha-helix-rich domain. By in situ RNA hybridization we could demonstrate the mainly epithelial expression of the C13 mRNA in prostatic tissue. CONCLUSIONS: The localization of C13 between the tumor suppressor genes BRCA-2 and RB-1, the detected allelic imbalances, the downregulation of its mRNA in some prostatic cancer tissues, the epithelial expression and the described protein structure suggest that this gene encodes a protein that may have tumor or metastasis suppressing function in prostate tissue.


Asunto(s)
Cromosomas Humanos Par 13/genética , ADN de Neoplasias/genética , Proteínas de Neoplasias/genética , Neoplasias de la Próstata/genética , Proteína de Retinoblastoma/genética , Factores de Transcripción/genética , Proteína BRCA2 , ADN Complementario/genética , ADN Complementario/aislamiento & purificación , ADN Complementario/metabolismo , ADN de Neoplasias/aislamiento & purificación , ADN de Neoplasias/metabolismo , Perfilación de la Expresión Génica , Genes Supresores de Tumor , Humanos , Hibridación Fluorescente in Situ , Pérdida de Heterocigocidad , Masculino , Proteínas de Neoplasias/química , Neoplasias de la Próstata/química , ARN Mensajero/biosíntesis , ARN Mensajero/genética , ARN Neoplásico/biosíntesis , ARN Neoplásico/genética , Mapeo de Híbrido por Radiación , Técnica del ADN Polimorfo Amplificado Aleatorio , Proteína de Retinoblastoma/química , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Transcripción/química
13.
Bioessays ; 22(4): 316-26, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10723029

RESUMEN

The precise, sequence-specific regulation of RNA synthesis is the primary mechanism underlying differential gene expression. This general statement applies to both prokaryotic and eukaryotic organisms, as well as to their viral pathogens. Thus, it is not surprising that genomes use a substantial portion of their protein-coding content to regulate the process of RNA synthesis. Transcriptional regulation in bacterial systems is particularly well understood. In this essay, we build on this knowledge and propose two opposing models to describe promoter opening and transcription initiation in the eukaryotic RNA polymerase II system. Promoter opening in the "twisting by cranking" model is based on changes in the trajectory of DNA. In contrast, invasion of single-stranded DNA-binding proteins between the DNA strands drives the reaction in the "peeling by binding" model.


Asunto(s)
Modelos Genéticos , Regiones Promotoras Genéticas , ARN Polimerasa II/metabolismo , Transcripción Genética , Adenosina Trifosfato/metabolismo , Animales , ADN de Cadena Simple , Regulación Bacteriana de la Expresión Génica , Humanos , Hidrólisis , Isomerismo
14.
J Biol Chem ; 275(6): 4258-66, 2000 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-10660593

RESUMEN

TFIIH is a multisubunit protein complex involved in RNA polymerase II transcription and nucleotide excision repair, which removes a wide variety of DNA lesions including UV-induced photoproducts. Mutations in the DNA-dependent ATPase/helicase subunits of TFIIH, XPB and XPD, are associated with three inherited syndromes as follows: xeroderma pigmentosum with or without Cockayne syndrome and trichothiodystrophy. By using epitope-tagged XPD we purified mammalian TFIIH carrying a wild type or an active-site mutant XPD subunit. Contrary to XPB, XPD helicase activity was dispensable for in vitro transcription, catalytic formation of trinucleotide transcripts, and promoter opening. Moreover, in contrast to XPB, microinjection of mutant XPD cDNA did not interfere with in vivo transcription. These data show directly that XPD activity is not required for transcription. However, during DNA repair, neither 5' nor 3' incisions in defined positions around a DNA adduct were detected in the presence of TFIIH containing inactive XPD, although substantial damage-dependent DNA synthesis was induced by the presence of mutant XPD both in cells and cell extracts. The aberrant damage-dependent DNA synthesis caused by the mutant XPD does not lead to effective repair, consistent with the discrepancy between repair synthesis and survival in cells from a number of XP-D patients.


Asunto(s)
ADN Helicasas/genética , Reparación del ADN/genética , Proteínas de Unión al ADN , Proteínas/genética , Factores de Transcripción TFII , Factores de Transcripción/genética , Transcripción Genética , Adenosina Trifosfatasas/metabolismo , Animales , Células CHO , Línea Celular , Síndrome de Cockayne/genética , Cricetinae , ADN/biosíntesis , Daño del ADN/genética , Humanos , Mutagénesis Sitio-Dirigida , Mutación , Permanganato de Potasio/farmacología , Factor de Transcripción TFIIH , Factores de Transcripción/metabolismo , Rayos Ultravioleta , Xerodermia Pigmentosa/genética , Proteína de la Xerodermia Pigmentosa del Grupo D
15.
Plant Mol Biol ; 38(1-2): 101-9, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9738962

RESUMEN

Expression and stability of immunoglobulins in transgenic plants have been investigated and optimized by accumulation in different cellular compartments as cytosol, apoplastic space and endoplasmic reticulum (ER) as will be discussed in this review. In several cases described the highest accumulation of complete active antibodies was achieved by targeting into the apoplastic space. High-level expression of active recombinant single-chain Fv antibodies (scFv's) was obtained by retention of these proteins in the lumen of the endoplasmic reticulum. This has been shown for leaves and seeds of transgenic tobacco as well as for potato tubers. Transgenic tobacco seeds, potato tubers and tobacco leaves can facilitate stable storage of scFv's accumulated in the ER over an extended (seeds, tubers) or a short (leaves) period of time. The expression of specific scFv's in different plant species, plant organs and cellular compartments offers the possibility of blocking regulatory factors or pathogens specifically. Examples are scFv's expressed in the cytosol and the apoplastic space of transgenic plant cells modulating the infection process of plant viruses and a cytosolically expressed scFv that influenced the activity of phytochrome A protein. The immunomodulation approach has been shown to be also applicable for investigating the action of the phyto-hormone abscisic acid (ABA). High-level accumulation of specific anti-ABA scFv's in the ER of all leaf cells has been used to block the influence of ABA on the stomatal functions. Seed-specific expression of high amounts of anti-ABA-scFv's at a defined time of seed-development induced a developmental switch from seed ripening to vegetative growth. It has been demonstrated that ER retention is essential for the accumulation of sufficient scFv to bind high concentrations of ABA in the transgenic seeds.


Asunto(s)
Adyuvantes Inmunológicos/fisiología , Compartimento Celular/inmunología , Inmunoglobulinas/genética , Virus de Plantas/inmunología , Plantas Modificadas Genéticamente/inmunología , Plantas Modificadas Genéticamente/virología , Proteínas Recombinantes/metabolismo , Animales , Humanos , Inmunoglobulinas/biosíntesis , Inmunoglobulinas/química , Inmunoglobulinas/metabolismo , Virus de Plantas/genética , Virus de Plantas/patogenicidad , Plantas Modificadas Genéticamente/metabolismo , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/síntesis química , Proteínas Recombinantes/inmunología
16.
Mutat Res ; 398(1-2): 101-10, 1998 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-9626970

RESUMEN

The parameter tail moment in single cell gel electrophoresis (comet assay) is calculated as the product of the two values: the percentage of DNA in the comet tail and the tail length in microm. Experiments were performed with cultured mammalian cells: B-Lymphoblasts, epithelial cells of a kidney tissue and a plate-epithelial cell line of a human carcinoma. They were irradiated in suspension with UV A at lambda = 343 nm, generated by an excimer laser-pumped dye laser. DNA migration was assessed and analysed. It is demonstrated that the distribution of the tail moments can be fitted by a chi2 (chi-square) distribution, whereas the factors of the product tail moment tend to be normally distributed. From this result, consequences for the statistical evaluation of the results can arise, especially for the computation of the confidence limits and for the valuation of the parameter tail moment from other comet assay experiments.


Asunto(s)
Electroforesis/métodos , Células Cultivadas , Distribución de Chi-Cuadrado , Humanos , Células Tumorales Cultivadas , Rayos Ultravioleta
17.
Urology ; 51(1): 94-8, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9457296

RESUMEN

OBJECTIVES: To investigate the effects of oral oxybutynin chloride (OC) on standard urodynamic measures in children with myelomeningocele (MMC) and detrusor hyperreflexia. METHODS: Forty-one MMC children with detrusor hyperreflexia (19 boys and 22 girls, aged 2 months to 15 years; mean 4.9 years) were evaluated urodynamically before and within 3 months after initiation of oral OC therapy (0.2 to 0.3 mg/kg/day). Therapy with oral OC was always combined with clean intermittent catheterization (CIC). RESULTS: Oral OC treatment caused an increase in bladder capacity from 141 +/- 96 to 197 +/- 99 mL (+ 40%; P < 0.01), a decrease in detrusor pressure at maximal capacity from 45 +/- 32 to 28 +/- 23 cm H2O (-38%; P < 0.01), and an increase in detrusor compliance from 6.5 +/- 5.6 to 16.8 +/- 13.7 mL/cm H2O (+ 158%; P < 0.01). Improvement in urodynamic measures and continence were correlated. After a follow-up of at least 2 years, effective protection of renal function was achieved in 38 of the 41 children (93%) with conservative therapy alone. Adverse effects resulted in discontinuation of oral OC treatment in only 2 cases. CONCLUSIONS: Treatment with oral OC and CIC is effective and safe in children with MMC and detrusor hyperreflexia and should be initiated early when indicated by urodynamic findings.


Asunto(s)
Antagonistas Colinérgicos/administración & dosificación , Ácidos Mandélicos/administración & dosificación , Meningomielocele/fisiopatología , Reflejo Anormal/efectos de los fármacos , Vejiga Urinaria/efectos de los fármacos , Vejiga Urinaria/fisiopatología , Urodinámica/efectos de los fármacos , Administración Oral , Adolescente , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Vejiga Urinaria/inervación
18.
Immunotechnology ; 3(3): 205-16, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9358273

RESUMEN

BACKGROUND: Plants offer various advantages for the production of pharmaceutical proteins over conventional production systems such as bacterial or mammalian cell culture. In order to explore transgenic plants for large-scale production and storage of recombinant antibodies we tried to optimize the accumulation and stability of functionally active single chain Fv (scFv) antibodies in transgenic tobacco plants. OBJECTIVES: Two different scFv antibodies which were expressed in different plant organs and plant cell compartments have been used for the study. Accumulation levels and antibody properties such as stability and antigen-binding activity were investigated. STUDY DESIGN: For ubiquitous expression in tobacco plants, transcription of the scFv genes was controlled by the strong cauliflower mosaic virus (CaMV) 35S promoter. We used seed specific legumin B4 (LeB4) and the unknown seed protein (USP) promoters from Vicia faba for storage organ specific expression. RESULTS: High accumulation of the two different scFv proteins in transgenic tobacco plants was only achieved by retention of the recombinant antibodies in the lumen of the endoplasmic reticulum (ER). Expression levels of scFv antibodies reached up to 4-6.8% of total soluble proteins (TSP) in leaves and up to 3-4% in ripe tobacco seeds. Transgenic tobacco seeds as well as tobacco leaves facilitated stable storage of ER-accumulated scFvs over an extended (seeds) or a short (leaves) period of time. Functionally active scFv proteins could be extracted after harvesting of the leaf material--drying and storage for 1 week at room temperature. Both the amount and the binding activity of the scFv proteins remained unchanged. CONCLUSION: A plant expression system where the scFv-proteins are targeted in the ER provides not only the highest accumulation level of active single chain Fv antibodies ever reported but also a short- or long-term storage of the foreign protein in the harvested plant material.


Asunto(s)
Fragmentos de Inmunoglobulinas/biosíntesis , Región Variable de Inmunoglobulina/biosíntesis , Nicotiana/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Plantas Tóxicas , Quimera , Ensayo de Inmunoadsorción Enzimática , Genes de Plantas , Fragmentos de Inmunoglobulinas/genética , Fragmentos de Inmunoglobulinas/metabolismo , Región Variable de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Plantas Modificadas Genéticamente/genética , Nicotiana/genética , Transformación Genética
19.
EMBO J ; 16(15): 4489-96, 1997 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-9303293

RESUMEN

A single-chain Fv antibody (scFv) gene, which has previously been used to immunomodulate abscisic acid (ABA) activity in transgenic tobacco to create a 'wilty' phenotype, was put under control of the seed-specific USP promoter from Vicia faba and used to transform tobacco. Transformants were phenotypically similar to wild-type plants apart from their seeds. Anti-ABA scFv embryo development differed markedly from wild-type embryo development. Seeds which accumulated similar levels of a scFv that binds to oxazolone, a hapten absent from plants, developed like wild-type embryos. Anti-ABA scFv embryos developed green cotyledons containing chloroplasts and accumulated photosynthetic pigments but produced less seed storage protein and oil bodies. Anti-ABA scFv seeds germinated precociously if removed from seed capsules during development but were incapable of germination after drying. Total ABA levels were higher than in wild-type seeds but calculated free ABA levels were near-zero until 21 days after pollination. We show for the first time seed-specific immunomodulation and the resulting switch from the seed maturation programme to a germination programme. We conclude that the immunomodulation of hormones can alter the development programme of target organs, allowing the study of the directly blocked endogenous molecules and manipulation of the system concerned.


Asunto(s)
Ácido Abscísico/metabolismo , Semillas/inmunología , Semillas/metabolismo , Ácido Abscísico/antagonistas & inhibidores , Ácido Abscísico/inmunología , Secuencia de Aminoácidos , Fabaceae/genética , Genes de Plantas , Fragmentos de Inmunoglobulinas/genética , Fenotipo , Plantas Modificadas Genéticamente , Plantas Medicinales , Plantas Tóxicas , Regiones Promotoras Genéticas , Ingeniería de Proteínas , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Semillas/genética , Nicotiana/genética , Nicotiana/inmunología , Nicotiana/metabolismo
20.
EMBO J ; 16(24): 7468-80, 1997 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-9405375

RESUMEN

We have analyzed transcription initiation by RNA polymerase II (pol II) in a highly efficient in vitro transcription system composed of essentially homogeneous protein preparations. The pol II complex was stalled on adenovirus major late promoter templates at defined positions, and the open region and RNA products of these complexes were examined. The first transition is formation of the open complex, which can be reversed by addition of ATPgammaS. The open region is no longer sensitive to ATPgammaS after formation of a four-nucleotide RNA, which constitutes the second transition. This indicates that the ATP-dependent DNA helicase activity of TFIIH is required to maintain the open region only during formation of the first three phosphodiester bonds. The downstream part of the transcription bubble expands in a continuous motion, but the initially opened region (-9/-2 on the non-template strand) recloses abruptly when transcription reaches register 11. This third transition is accompanied by a switch from abortive to productive RNA synthesis, which implies promoter clearance. Our findings provide a framework to analyze regulation of these specific transitions during transcription initiation by pol II.


Asunto(s)
ADN Helicasas/metabolismo , Regiones Promotoras Genéticas , ARN Polimerasa II/metabolismo , Factores de Transcripción TFII , Factores de Transcripción/metabolismo , Transcripción Genética , Adenosina Trifosfato/análogos & derivados , Adenosina Trifosfato/metabolismo , Adenosina Trifosfato/farmacología , Adenoviridae/genética , Animales , Secuencia de Bases , Bovinos , Células HeLa , Humanos , Cinética , Regiones Promotoras Genéticas/efectos de los fármacos , ARN Polimerasa II/química , ARN Viral/biosíntesis , Proteínas Recombinantes/metabolismo , Moldes Genéticos , Timo/enzimología , Factor de Transcripción TFIIH
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