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2.
Strahlenther Onkol ; 192(11): 789-796, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27377261

RESUMEN

BACKGROUND: Radiosurgical treatment of brain metastases is well established in daily clinical routine. Utilization of flattening-filter-free beams (FFF) may allow for more rapid delivery of treatment doses and improve clinical comfort. Hence, we compared plan quality and efficiency of radiosurgery in FFF mode to FF techniques. MATERIALS AND METHODS: Between November 2014 and June 2015, 21 consecutive patients with 25 brain metastases were treated with stereotactic radiosurgery (SRS) in FFF mode. Brain metastases received dose-fractionation schedules of 1 × 20 Gy or 1 × 18 Gy, delivered to the conformally enclosing 80 % isodose. Three patients with critically localized or large (>3 cm) brain metastases were treated with 6 × 5 Gy. Plan quality and efficiency were evaluated by analyzing conformity, dose gradients, dose to healthy brain tissue, treatment delivery time, and number of monitor units. FFF plans were compared to those using the FF method, and early clinical outcome and toxicity were assessed. RESULTS: FFF mode resulted in significant reductions in beam-on time (p < 0.001) and mean brain dose (p = 0.001) relative to FF-mode comparison plans. Furthermore, significant improvements in dose gradients and sharper dose falloffs were found for SRS in FFF mode (-1.1 %, -29.6 %; p ≤ 0.003), but conformity was slightly superior in SRS in FF mode (-1.3 %; p = 0.001). With a median follow-up time of 5.1 months, 6­month overall survival was 63.3 %. Local control was observed in 24 of 25 brain metastases (96 %). CONCLUSION: SRS in FFF mode is time efficient and provides similar plan quality with the opportunity of slightly reduced dose exposure to healthy brain tissue when compared to SRS in FF mode. Clinical outcomes appear promising and show only modest treatment-related toxicity.


Asunto(s)
Lesiones Encefálicas/etiología , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundario , Traumatismos por Radiación/etiología , Radiocirugia/efectos adversos , Planificación de la Radioterapia Asistida por Computador/métodos , Anciano , Anciano de 80 o más Años , Lesiones Encefálicas/prevención & control , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Traumatismos por Radiación/prevención & control , Radiocirugia/métodos , Dosificación Radioterapéutica , Radioterapia Asistida por Computador/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Resultado del Tratamiento
3.
Zentralbl Chir ; 139 Suppl 1: S6-12, 2014 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-25264727

RESUMEN

The aim of preoperative lung function analysis and diagnostic cardiology is to identify patients with an increased risk of complications and to best inform the patients about treatment options and risks so that an informed treatment decision can be made. The identification of patients at increased peri-interventional risk by preoperative physiological diagnostics also forms the basis for further developments and improvements of interventions and intervention techniques in order to reduce the risk of complications. The acquisition of a detailed medical history, a thorough physical examination, and the diagnosis using ECG and spirometry may provide the first evidence for the presence of relevant comorbidities. In elective surgery a detailed preoperative evaluation of comorbidities must be done. The association of age and operative mortality is not only due to age alone, but also involves the spectrum of comorbidities. The algorithms for Germany are based on the "S3 Guidelines of the German Society of Pneumology of 2010". Both German and international guidelines recommend the discussion of each case before lung resections in an interdisciplinary case discussion with thoracic surgeons, oncologists, radio-oncologists and pulmonologists. Patients of advanced age should always be subjected to an extended preoperative cardiopulmonary investigation.


Asunto(s)
Pruebas de Función Cardíaca , Cuidados Preoperatorios , Pruebas de Función Respiratoria , Medición de Riesgo , Procedimientos Quirúrgicos Torácicos , Humanos , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/prevención & control
4.
Nat Med ; 7(8): 920-6, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11479624

RESUMEN

Integase interactor 1 (INI1), also known as hSNF5, is a protein that interacts with HIV-1 integrase. We report here that a cytoplasmically localized fragment of INI1 (S6; aa183-294) containing the minimal integrase-interaction domain potently inhibits HIV-1 particle production and replication. Mutations in S6 or integrase that disrupt integrase-INI1 interaction abrogated the inhibitory effect. An integrase-deficient HIV-1 transcomplemented with integrase fused to Vpr was not affected by S6. INI1 was specifically incorporated into virions and was required for efficient HIV-1 particle production. These results indicate that INI1 is required for late events in the viral life cycle, and that ectopic expression of S6 inhibits HIV-1 replication in a transdominant manner via its specific interaction with integrase within the context of Gag-Pol, providing a novel strategy to control HIV-1 replication.


Asunto(s)
Proteínas de Unión al ADN/fisiología , VIH-1/ultraestructura , Virión/metabolismo , Secuencia de Bases , Línea Celular , Núcleo Celular/metabolismo , Proteínas Cromosómicas no Histona , Citoplasma/metabolismo , Cartilla de ADN , Proteínas de Unión al ADN/genética , Genes Dominantes , Humanos , Proteína SMARCB1 , Factores de Transcripción
5.
Neuroimage ; 47(1): 392-402, 2009 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-19345269

RESUMEN

This fMRI study examined which structures of a proposed dorsal stream system are involved in the auditory-motor integration during fast overt repetition. We used a shadowing task which requires immediate repetition of an auditory-verbal input and is supposed to elicit unconscious imitation effects of phonologically irrelevant speech parameters. Subjects' responses were recorded in the scanner. To examine automated auditory-motor mapping of speech gestures of others onto one's own speech production system we contrasted the shadowing of pseudowords produced by multiple speakers (men, women, and children) with the shadowing of pseudowords produced by a single speaker. Furthermore, we asked whether behavioral variables predicted changes in functional activation during shadowing. Shadowing multiple speakers compared to a single speaker elicited increased bilateral activation predominantly in the superior temporal sulci. These regions may mediate acoustic-phonetic speaker normalization in preparation of a translation of perceptual into motor information. Additional activation in Broca's area and the thalamus may reflect motor effects of the adaptation to multiple speaker models. Item-wise correlational analyses of response latencies with BOLD signal changes indicated that longer latencies were associated with increased activation in the left parietal operculum, suggesting that this area plays a central role in the actual transfer of auditory-verbal information to speech motor representations. A multiple regression of behavioral with imaging data showed activation in a right inferior parietal area near the temporo-parietal boundary which correlated positively with the degree of speech rate imitation and negatively with response latency. This activation may be attributable to attentional and/or paralinguistic processes.


Asunto(s)
Encéfalo/fisiología , Conducta Imitativa/fisiología , Habla/fisiología , Estimulación Acústica , Adulto , Mapeo Encefálico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Actividad Motora/fisiología , Análisis de Regresión , Percepción del Habla/fisiología , Análisis y Desempeño de Tareas , Factores de Tiempo , Adulto Joven
6.
Science ; 240(4858): 1525-9, 1988 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-3375832

RESUMEN

Clinical and seroepidemiological studies in West Africa indicate that human immunodeficiency virus type 2 (HIV-2) is widespread and associated with immunodeficiency states of variable degree. In this study, an isolate of HIV-2 from a patient in Senegal was molecularly cloned and characterized. This isolate (HIV-2ST) was shown by hybridization and restriction enzyme analysis to be more related to the prototype HIV-2ROD than to other human or primate retroviruses. Cultures of HIV-2ST showed genotypic polymorphism, and clones of the virus had transmembrane envelope glycoproteins of 30 and 42 kilodaltons. Unlike other immunodeficiency viruses, HIV-2ST did not cause cell death or induce cell fusion in peripheral blood lymphocytes or in any of four CD4+ cell lines tested. Although HIV-2ST entered cells by a CD4-dependent mechanism and replicated actively, cell-free transmission of the virus was retarded at the level of cell entry. These findings suggest that immunodeficiency viruses prevalent in West African populations are members of the HIV-2 virus group and that certain strains of this virus have attenuated virulence.


Asunto(s)
VIH/aislamiento & purificación , Línea Celular , Supervivencia Celular , ADN Viral/genética , Genes Virales , VIH/clasificación , VIH/patogenicidad , Humanos , Cinética , Linfocitos/microbiología , Senegal , Especificidad de la Especie
7.
Science ; 259(5102): 1749-54, 1993 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-8096089

RESUMEN

Quantitative competitive polymerase chain reaction (QC-PCR) methods were used to quantify virion-associated human immunodeficiency virus type-1 (HIV-1) RNA in plasma from 66 patients with Centers for Disease Control stage I to IVC1 infection. HIV-1 RNA, ranging from 100 to nearly 22,000,000 copies per milliliter of plasma (corresponding to 50 to 11,000,000 virions per milliliter), was readily quantified in all subjects, was significantly associated with disease stage and CD4+ T cell counts, and decreased by as much as 235-fold with resolution of primary infection or institution of antiretroviral therapy. Plasma virus levels determined by QC-PCR correlated with, but exceeded by an average of 60,000-fold, virus titers measured by endpoint dilution culture. Quantitation of HIV-1 in plasma by QC-PCR may be useful in assessing the efficacy of antiretroviral agents, especially in early stage disease when conventional viral markers are often negative.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/microbiología , VIH-1/aislamiento & purificación , Reacción en Cadena de la Polimerasa , ARN Viral/sangre , Síndrome de Inmunodeficiencia Adquirida/sangre , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Linfocitos T CD4-Positivos/patología , VIH-1/genética , VIH-1/fisiología , Humanos , Recuento de Leucocitos , Ultracentrifugación , Replicación Viral , Zidovudina/uso terapéutico
8.
Eur Radiol ; 19(10): 2391-402, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19458953

RESUMEN

Characterisation and quantification of emphysema are necessary for planning of local treatment and monitoring. Sensitive, easy to measure, and stable parameters have to be established and their relation to the well-known pulmonary function testing (PFT) has to be investigated. A retrospective analysis of 221 nonenhanced thin-section MDCT with a corresponding PFT was carried out, with a subgroup analysis in 102 COPD stage III+IV, 44 COPD stage 0, and 33 investigations into interstitial lung disease (ILD). The in-house YACTA software was used for automatic quantification of lung and emphysema volume [l], emphysema index, mean lung density (MLD [HU]) and 15(th) percentile [HU]. CT-derived lung volume is significantly smaller in ILD (3.8) and larger in COPD (7.2) than in controls (5.9, p < 0.0001). Emphysema volume and index are significantly higher in COPD than in controls (3.2 vs. 0.5, p < 0.0001, 45% vs. 8%, p < 0.0001). MLD and 15(th) percentile are significantly smaller in COPD (-877/-985, p < 0.0001) and significantly higher in ILD (-777, p < 0.0006/-914, p < 0.0001) than in controls (-829/-935). A relevant amount of COPD patients apparently do not suffer from emphysema, while controls who do not fulfil PFT criteria for COPD also demonstrate CT features of emphysema. Automatic quantification of thin-section CT delivers convincing parameters and ranges that are able to differentiate among emphysema, control and ILD. An emphysema index of lower 20%, MLD higher than -850, and 15(th) percentile lower than -950 might be regarded as normal (thin-section, nonenhanced, B40, YACTA). These ranges might be helpful in the judgement of individual measures.


Asunto(s)
Inteligencia Artificial , Almacenamiento y Recuperación de la Información/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Enfisema Pulmonar/diagnóstico , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Pruebas de Función Respiratoria , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
9.
Clin Exp Metastasis ; 24(5): 389-401, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17541709

RESUMEN

This study sought to determine if weekly X-ray exposure affected breast cancer cell metastasis to bone and to also evaluate the use of bioluminescent imaging (BLI) and microSPECT for detection of metastatic bone lesions. Five week old nude mice were randomly assigned to the CT exposed (n = 7) and no CT exposure (n = 6) treatment groups. Mice received an intracardiac injection of MDA-MB-435 human breast cancer cells transduced with luciferase, or a sham injection (saline). The CT exposed group of mice received CT irradiation once a week for 5 weeks. All mice underwent weekly BLI and select mice received Tc-99m-MDP followed by microSPECT imaging after 5 weeks. Pathological evaluation and histomorphometry were used to assess the affect of CT X-rays on bone metastasis and to evaluate BLI. BLI results found no significant difference in metastasis between animals that received CT and those that did not (P > 0.05); however, histomorphometry of the knee joints revealed a significant increase (P = 0.029) in tumor area of the leg bones in mice that received CT exposure (60% +/- 7%) compared to animals that did not receive CT scans (33% +/- 8%). Compared to histological analysis, BLI of the leg and spine was determined to have excellent sensitivity (100%), good specificity (80-90%) and accuracy (90-96%), a positive predictive value of 81-93% and a 100% negative predictive value. Thus, multi-modality imaging techniques can be very useful for monitoring bone metastasis, however microCT X-rays should be used judiciously in order to limit irradiation that may stimulate increased metastasis to specific regions of the skeleton. MicroSPECT imaging did not detect metastatic lesions in the legs of these young nude mice.


Asunto(s)
Neoplasias Óseas/diagnóstico por imagen , Neoplasias Mamarias Experimentales/patología , Animales , Neoplasias Óseas/secundario , Huesos/patología , Línea Celular Tumoral , Femenino , Humanos , Luminiscencia , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Especificidad de Órganos , Valor Predictivo de las Pruebas , Distribución Aleatoria , Tomografía Computarizada de Emisión de Fotón Único/métodos , Tomografía Computarizada por Rayos X/efectos adversos , Tomografía Computarizada por Rayos X/métodos , Trasplante Heterólogo
10.
Protein Eng Des Sel ; 30(10): 729-741, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29053845

RESUMEN

The Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) is a plasma membrane chloride channel protein that regulates vertebrate fluid homeostasis. The inefficiency of wild type human CFTR protein folding/trafficking is exacerbated by genetic mutations that can cause protein misfolding in the endoplasmic reticulum (ER) and subsequent degradation. This project investigates small changes in protein sequence that can alter the thermal stability of the large multi-domain CFTR protein. We target a conserved 70-residue α-subdomain located in the first nucleotide-binding domain that hosts the common misfolding mutation ∆F508. To investigate substitutions that can stabilize this domain, we constructed chimeras between human CFTR and its closest yeast homolog Yor1p. The α-subdomain of Yor1p was replaced with that of CFTR in Saccharomyces cerevisiae. Cellular localization of green fluorescence protein-tagged Yor1p-CFTR chimeras was analyzed by fluorescence microscopy and quantitative multispectral imaging flow cytometry, steady-state protein levels were compared by SDS-PAGE and protein function probed by a phenotypic oligomycin resistance assay. The chimeras exhibited ER retention in yeast characteristic of defective protein folding/processing. Substitution of seven CFTR α-subdomain residues that are highly conserved in Yor1p and other transporters but differ in CFTR (S495P/R516K/F533L/A534P/K536G/I539T/R553K) improved Yor1p-CFTR chimera localization to the yeast plasma membrane. When introduced into human CFTR expressed in mammalian cells, the same substitutions improve the purified protein thermal stability. This stabilized human CFTR protein will be directly useful for structural and biophysical studies that have been limited by the thermal sensitivity of wild type CFTR. The insights into critical structural residues within CFTR could facilitate development of effective therapeutics for CF-causing mutations.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/química , Sustitución de Aminoácidos , Regulador de Conductancia de Transmembrana de Fibrosis Quística/química , Retículo Endoplásmico/metabolismo , Proteínas Mutantes Quiméricas/química , Proteínas de Saccharomyces cerevisiae/química , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Secuencia de Aminoácidos , Animales , Sitios de Unión , Células CHO , Cricetulus , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Calor , Humanos , Modelos Moleculares , Proteínas Mutantes Quiméricas/genética , Proteínas Mutantes Quiméricas/metabolismo , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Pliegue de Proteína , Dominios y Motivos de Interacción de Proteínas , Estabilidad Proteica , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Relación Estructura-Actividad
11.
Mucosal Immunol ; 10(2): 531-544, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27579858

RESUMEN

Dendritic cells (DCs) throughout the female reproductive tract (FRT) were examined for phenotype, HIV capture ability and innate anti-HIV responses. Two main CD11c+ DC subsets were identified: CD11b+ and CD11blow DCs. CD11b+CD14+ DCs were the most abundant throughout the tract. A majority of CD11c+CD14+ cells corresponded to CD1c+ myeloid DCs, whereas the rest lacked CD1c and CD163 expression (macrophage marker) and may represent monocyte-derived cells. In addition, we identified CD103+ DCs, located exclusively in the endometrium, whereas DC-SIGN+ DCs were broadly distributed throughout the FRT. Following exposure to GFP-labeled HIV particles, CD14+ DC-SIGN+ as well as CD14+ DC-SIGN- cells captured virus, with ∼30% of these cells representing CD1c+ myeloid DCs. CD103+ DCs lacked HIV capture ability. Exposure of FRT DCs to HIV induced secretion of CCL2, CCR5 ligands, interleukin (IL)-8, elafin, and secretory leukocyte peptidase inhibitor (SLPI) within 3 h of exposure, whereas classical pro-inflammatory molecules did not change and interferon-α2 and IL-10 were undetectable. Furthermore, elafin and SLPI upregulation, but not CCL5, were suppressed by estradiol pre-treatment. Our results suggest that specific DC subsets in the FRT have the potential for capture and dissemination of HIV, exert antiviral responses and likely contribute to the recruitment of HIV-target cells through the secretion of innate immune molecules.


Asunto(s)
Células Dendríticas/inmunología , Genitales Femeninos/inmunología , Infecciones por VIH/inmunología , VIH/inmunología , Inmunidad Innata , Antígeno CD11c/metabolismo , Moléculas de Adhesión Celular/metabolismo , Células Cultivadas , Quimiocina CCL2/metabolismo , Células Dendríticas/virología , Elafina/metabolismo , Estradiol/farmacología , Femenino , VIH/patogenicidad , Infecciones por VIH/transmisión , Humanos , Interleucina-8/metabolismo , Lectinas Tipo C/metabolismo , Receptores de Lipopolisacáridos/metabolismo , Fagocitosis , Receptores CCR5/metabolismo , Receptores de Superficie Celular/metabolismo , Inhibidor Secretorio de Peptidasas Leucocitarias/metabolismo
13.
AIDS ; 7 Suppl 2: S65-71, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7909227

RESUMEN

OBJECTIVES: To better characterize viral load profiles through the course of HIV-1 disease and in response to treatment, and to further evaluate quantitative competitive polymerase chain reaction for measurement of viral load, we extended our comparative evaluation of this and other viral load measurements to a total of 118 patients, representing all stages of HIV-1 disease. DESIGN: For cross-sectional analysis across the spectrum of HIV-1 disease, plasma viral load was evaluated in 112 HIV-1-infected patients by quantitative competitive polymerase chain reaction analysis, plasma p24 antigen assay, plasma immune complex-dissociated p24 antigen assay and an endpoint dilution viral culture. Longitudinal specimens from six additional patients were analyzed, extending from the time of presentation with symptomatic acute HIV-1 infection through up to more than 2 years of follow-up. Longitudinal specimens were also studied for three patients over the period of initiation of zidovudine treatment, for 6 weeks of treatment and following temporary withdrawal of the treatment. METHODS: All measurement techniques were assessed in replicate aliquots of plasma. RESULTS: Quantitative competitive polymerase chain reaction was the most sensitive measure of viral load, and was best correlated with CD4+ T-cell counts. In longitudinally studied patients, this technique also allowed measurement of plasma virus levels throughout the period of follow-up, even when culture and p24 assays became negative following resolution of acute HIV-1 infection. The quantitative competitive polymerase chain reaction was also able to detect rapid and substantial changes in viral load associated with initiation and temporary withdrawal of antiviral treatment. CONCLUSIONS: The quantitative competitive polymerase chain reaction is promising as a sensitive and accurate method for measuring plasma viral load in HIV-1-infected patients, and is useful for following changes in viral load over the natural history of infection and following treatment intervention. The technique is particularly useful for patients with > 200 x 10(6) CD4+ T cells/l, in whom other viral markers are typically negative.


Asunto(s)
Infecciones por VIH/microbiología , VIH-1/genética , VIH-1/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Viremia/microbiología , Biomarcadores/sangre , Linfocitos T CD4-Positivos , Estudios de Evaluación como Asunto , Proteína p24 del Núcleo del VIH/sangre , Infecciones por VIH/sangre , Infecciones por VIH/tratamiento farmacológico , VIH-1/inmunología , Humanos , Recuento de Leucocitos , Reacción en Cadena de la Polimerasa/estadística & datos numéricos , ARN Viral/sangre , ARN Viral/genética , Sensibilidad y Especificidad , Factores de Tiempo , Viremia/sangre , Viremia/tratamiento farmacológico , Zidovudina/uso terapéutico
14.
AIDS Res Hum Retroviruses ; 11(3): 405-8, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7786585

RESUMEN

Antisera suitable for detection of SIVSM or SIVMAC Vpr proteins on Western blots of purified virions are currently not available. We have expressed the Vpr protein of SIVSMPBj1.9 in a gst-based prokaryotic expression system and used it to raise polyclonal antisera in rabbits. Two immune sera were obtained that specifically recognized both cell- and virion-associated Vpr protein on immunoblots of three different SIV isolates (SIVSMPBj1.9, SIVMACBK28, and SIVMAC239). Because Vpr is believed to play an important role in HIV/SIV replication and pathogenesis, these reagents will allow the extension of functional analyses of this protein to a broader spectrum of viruses. Both antisera and the gst-Vpr expression plasmid have been submitted to the NIAID AIDS Research and Reagent Program and are available to interested investigators.


Asunto(s)
Anticuerpos , Productos del Gen vpr/análisis , Productos del Gen vpr/biosíntesis , Virus de la Inmunodeficiencia de los Simios/fisiología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Línea Celular , Chlorocebus aethiops , Cartilla de ADN , Electroforesis en Gel de Poliacrilamida , Humanos , Immunoblotting , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Conejos/inmunología , Proteínas Recombinantes/análisis , Proteínas Recombinantes/biosíntesis , Virus de la Inmunodeficiencia de los Simios/química , Virus de la Inmunodeficiencia de los Simios/genética , Replicación Viral
15.
AIDS Res Hum Retroviruses ; 16(18): 1973-80, 2000 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-11153080

RESUMEN

The human endogenous retrovirus, type K (HERV-K) represents the most biologically active form of known retroelements present in the human genome. Several HERV-K genomes have transcriptionally active open reading frames and encode their own protease (PR). The HERV-K PR has been shown to authentically cleave human immunodeficiency virus type 1 (HIV-1) matrix-capsid peptide in the presence of HIV-1 PR inhibitors. This raised the possibility that HERV-K PR could complement HIV-1 PR function in HIV-1-infected individuals. To investigate this possibility, we fused the HIV-1 vpr gene to the HERV-K PR gene (vpr-PR). The vpr-PR expression plasmid and a PR-defective HIV-1 clone were cotransfected into 293T cells. Progeny virions were assayed for processing of the HIV-1 polyproteins by Western blot and for changes in infectivity. HERV-K PR fused to Vpr was incorporated into HIV-1 virions at a high concentration and cleaved the Gag and Pol precursor proteins. However, neither Gag nor Pol polyproteins were correctly processed. Moreover, the HERV-K PR did not restore virus infectivity. While these results do not exclude the possibility that the HERV-K PR could complement an HIV-1 PR whose function is impaired due to drugs or drug-resistant mutations, they clearly demonstrate that the HERV-K PR cannot substitute for the function of the wild-type HIV-1 PR.


Asunto(s)
Retrovirus Endógenos/enzimología , Endopeptidasas/metabolismo , Proteínas de Fusión gag-pol/metabolismo , VIH-1/enzimología , Precursores de Proteínas/metabolismo , Línea Celular , Endopeptidasas/genética , Productos del Gen vpr/metabolismo , Genes prv , Proteasa del VIH/genética , Proteasa del VIH/metabolismo , VIH-1/genética , Células HeLa , Humanos , Plásmidos/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Transfección , Virión/metabolismo , Virión/patogenicidad , Productos del Gen vpr del Virus de la Inmunodeficiencia Humana
16.
Dev Biol (Basel) ; 106: 237-48; discussion 249, 253-63, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11761237

RESUMEN

Lentiviral vectors hold great promise for gene therapy, and clinical trials to examine their safety and efficacy for treating human disease are being planned. The principle concern for safety is that genetic recombination among components of the vector could lead to the emergence of replication competent retrovirus (RCR). Using a sensitive method for detecting genetic recombination, we found that the current design of lentiviral vectors permits the generation of envelope-deficient recombinant lentivirus, stable integration of the recombinant into chromosomes of transduced cells, and mobilization of the recombinant genomes to other cells when pseudotyped with an exogenous envelope. We split the lentiviral packaging construct (Gag/Gag-Pol) into two separate parts: one that expresses Gag and Gag-Pro, and another that expresses Pol (reverse transcriptase [RT] and integrase [IN]) as a fusion partner of Vpr (Vpr-RT-IN). This "trans-lentiviral" vector efficiently transduces non-dividing cells and achieves titres greater than 10(6) U/ml or 10(8) IU/ml after concentration by ultracentrifugation. The trans-lentiviral vector disarms the Gag-Pol structure and prevents the generation of recombinants containing functional RT and IN. Since RT and IN are absolutely required for any type of RCR and DNA mobilization, this new class of lentiviral vector, in combination with our sensitive in vitro assay for monitoring regeneration of the gag-pol structure, offers a unique advantage for predicting vector safety for clinical applications.


Asunto(s)
Vectores Genéticos , VIH-1/genética , Recombinación Genética , Secuencia de Bases , Línea Celular , Cartilla de ADN , Humanos
17.
Clin Nucl Med ; 8(11): 540-2, 1983 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6653009

RESUMEN

A patient with gastroduodenal artery aneurysm detected with Tc-99m scintiangiography is described. Liver and hepatobiliary imaging were also performed on the patient. Ultrasound examination, arteriography, and surgical exploration were carried out. The value of radionuclide studies in leading to the proper diagnosis is emphasized.


Asunto(s)
Aneurisma/diagnóstico por imagen , Duodeno/irrigación sanguínea , Estómago/irrigación sanguínea , Anciano , Conductos Biliares Intrahepáticos/diagnóstico por imagen , Femenino , Vesícula Biliar/diagnóstico por imagen , Arteria Hepática/diagnóstico por imagen , Humanos , Cintigrafía , Ultrasonografía
18.
Dtsch Med Wochenschr ; 139(27): 1403-8, 2014 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-24937077

RESUMEN

BACKGROUND: Since 2000 the Thoraxklinik Heidelberg offers the primary smoking prevention program "ohnekippe" for children aged 12-14 years. This program was scientifically evaluated to test its efficacy and sustainability. METHODS: All pupils participating in this prevention program (n=1427) were asked to complete a written survey regarding their smoking behaviour at the time of intervention (baseline) and after one year. A control group (n=1412) without intervention from comparable schools and grades were questioned in parallel. Afterwards the program was modified with active involvement of schools and then data regarding smoking prevalence of young people were compared based on the microcensus 2005 and 2009. RESULTS: 187 (13,4 %) pupils in the intervention and 215 (15,4 %) pupils in the control group were smokers at baseline. One year after, the number of regular and occasional smokers had increased from 11.2 % to 21.2 % in both groups without significant differences. Besides age and initial smoking status the "peer group" had important influence on smoking behaviour of young people. After modifying the program the number of smoking young people in the catchment area of "ohnekippe" has decreased significantly (7.8 %). Overall smoking prevalence in this age group was much lower (11,8 %) than in the rest of Baden-Württemberg (16.0 %) and of Germany (17.5 %). CONCLUSION: Smoking prevention programs for young people can be effective if they are appropriately designed. Not only one prevention event, but intensive preparation and follow-up in schools as well as involvement of the "peer group" is essential for a successful intervention. After appropriate modification the smoking prevention program "ohnekippe" shows highly promising success.


Asunto(s)
Cooperación del Paciente/estadística & datos numéricos , Grupo Paritario , Servicios de Salud Escolar/estadística & datos numéricos , Cese del Hábito de Fumar/estadística & datos numéricos , Prevención del Hábito de Fumar , Fumar/epidemiología , Estudiantes/estadística & datos numéricos , Adolescente , Actitud Frente a la Salud , Niño , Femenino , Alemania/epidemiología , Humanos , Masculino , Prevalencia , Cese del Hábito de Fumar/métodos , Resultado del Tratamiento
20.
Dtsch Med Wochenschr ; 136(48): 2503-6, 2011 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-22109586

RESUMEN

BACKGROUND: Corynebacterium pseudodiphtheriticum is of increasing importance because of the rising number of immunocompromised patients. Pneumonia, but also endocarditis, urinary tract infections or keratitis can be caused by this bacteria in case of immunosuppression. Taking corynebacterium pseudodiphtheriticum into consideration as causitive agent provides for a fast onset of targeted antibiotic therapy. HISTORY AND FINDINGS: A 69-year-old man with immunoglobulin deficiency due to a chronic lymphocytic leukemia presented with typical clinical, laboratory and imaging evidence of pneumonia. DIAGNOSIS, TREATMENT AND COURSE: Corynebacterium pseudodiphtheriticum was detected as causative agent. After a prolongated course targeted antibiotic therapy and immunoglobulin substitution resulted in full recovery of the patient. CONCLUSION: In immunocompromised patients Corynebacterium pseudodiphtheriticum should be taken into consideration as causative bacterium of pneumonia. Especially, immunoglobuline deficiency seems to be associated with pneumonia caused by Corynebacterium pseudodiphtheriticum. Therefore, immunoglobulin substitution as well as a targeted antibiotic therapy should be considered.


Asunto(s)
Infecciones por Corynebacterium/diagnóstico , Infecciones por Corynebacterium/inmunología , Síndromes de Inmunodeficiencia/diagnóstico , Síndromes de Inmunodeficiencia/inmunología , Infecciones Oportunistas/diagnóstico , Infecciones Oportunistas/inmunología , Neumonía Bacteriana/diagnóstico , Neumonía Bacteriana/inmunología , Anciano , Anticuerpos Monoclonales de Origen Murino/efectos adversos , Anticuerpos Monoclonales de Origen Murino/uso terapéutico , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Técnicas Bacteriológicas , Diagnóstico Diferencial , Humanos , Síndromes de Inmunodeficiencia/inducido químicamente , Leucemia Linfocítica Crónica de Células B/complicaciones , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/inmunología , Masculino , Reacción en Cadena de la Polimerasa , Rituximab
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