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1.
Gene Ther ; 19(10): 1018-29, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22071971

RESUMO

Protection against epigenetic silencing is a desirable feature of future gene therapy vectors, in particular for those applications in which transgene expression will not confer growth advantage to gene-transduced cells. The ubiquitous chromatin opening element (UCOE) consisting of the methylation-free CpG island encompassing the dual divergently transcribed promoters of the human HNRPA2B1-CBX3 housekeeping genes (A2UCOE) has been shown to shield constitutive active heterologous promoters from epigenetic modifications and chromosomal position effects. However, it is unclear if this element can be used to improve expression from tissue-specific enhancer/promoters, while maintaining tissue specificity in hematopoietic cells. Here, we evaluated the potential of the A2UCOE in combination with the myeloid-specific myeloid related protein 8 (MRP8) promoter to target transgene expression specifically to myeloid cells in vitro and in vivo from a self-inactivating lentiviral vector. The inclusion of the A2UCOE did not interfere with specific upregulation of MRP8 promoter activity during myeloid differentiation and mediated sustained and vector copy-dependent expression in myeloid cells. Notably, the A2UCOE did not protect the MRP8 promoter from methylation in the P19 embryonal carcinoma cell line, suggesting that this element maintains the inherent epigenetic state and transcriptional activity of cellular promoters in their native configuration. Thus, the A2UCOE could represent a useful protective genetic element in gene therapy vectors, ensuring physiological transcriptional regulation of tissue-specific promoters independent of the chromosomal integration site.


Assuntos
Calgranulina A/genética , Proteínas Cromossômicas não Histona/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/genética , Lentivirus/genética , Regiões Promotoras Genéticas , Transgenes , Regulação para Cima , Animais , Linhagem Celular Transformada , Linhagem Celular Tumoral , Células Cultivadas , Proteínas Cromossômicas não Histona/metabolismo , Inativação Gênica , Genes Essenciais , Vetores Genéticos , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Humanos , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Mutantes , Células Mieloides/metabolismo , Células Mieloides/transplante , NADPH Oxidase 2 , NADPH Oxidases/genética , Transcrição Gênica
3.
J Anim Sci ; 76(3): 706-13, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9535327

RESUMO

This study considers a theory of risk as a means of coping with risk and uncertainty that have become a growing reality for animal agriculture. Microbial contaminations of food, waste management, animal products in the human diet, and transmissible spongiform encephalopathies (TSE) incorporate different conceptions of risk and require different approaches to handling the uncertainty involved. A dichotomous schema is suggested to assist understanding risk that may be adapted to recognizing and handling risk. The polar aspects of the proposal are the probabilistic approach at one end and the contextual understanding at the other. Probabilist conceptions of risk presume that risk is determined by probability and consequence. Contextual conceptions presume that management, law, regulation, media, and public perceptions, as well as the severity of the consequence, will figure prominently in decision making in the face of uncertainty. Relative emphasis on probabilistic characteristics shapes distinct understandings of risk that can be plotted between the poles. We are proposing that these conceptualizations need not be issues only for debate but also for recognition of the probabilistic or contextual nature of the risk. Specific actions and policy may be constructed on the basis of the conceptualization. The bovine spongiform encephalopathy/new variant Creutzfeldt-Jakob disease complex is examined philosophically and methodologically as a contextual challenge to animal agriculture and associated industries. As such, the TSE serve as a case study of effective application of risk theory to risks in animal agriculture.


Assuntos
Criação de Animais Domésticos/normas , Síndrome de Creutzfeldt-Jakob/prevenção & controle , Encefalopatia Espongiforme Bovina/prevenção & controle , Modelos Estatísticos , Animais , Bovinos , Síndrome de Creutzfeldt-Jakob/transmissão , Encefalopatia Espongiforme Bovina/transmissão , Microbiologia de Alimentos , Humanos , Probabilidade , Medição de Risco , Gerenciamento de Resíduos , Zoonoses
4.
J Nutr ; 126(9 Suppl): 2390S-2397S, 1996 09.
Artigo em Inglês | MEDLINE | ID: mdl-8811803

RESUMO

Evidence is provided showing that interests, values and belief systems have affected the development of Recommended Dietary Allowances (RDAs) and nutrition guidelines for Americans in the past and can be expected to do so in the future. The conflicts of the 1980s relative to the nutritional guidelines for Americans and the RDAs illustrate the tension among values that can parallel a conflict of interests. In the conflicts of the 1980s, we saw an apparent conflict between those policies that attempt to optimize outcomes for a large class of affected parties and those policies that attempt to establish constraints on actions which appear to threaten individual autonomy and freedom of choice. The former approach derives from utilitarian, consequential moral philosophy which evaluates policies by evaluating costs and harms, and weighing them against benefits to all parties. The latter has its strongest advocates in contemporary libertarianism which takes individual freedom to be the bottom line. Ethical vegetarianism, a belief system which would limit RDAs and guidelines to those that can be translated to vegan and other vegetarian diets, has been a more recent entry into the discussions. Such human value issues suggest that a set of RDAs or of nutrition guidelines is analogous to and may be considered to be an ethic. An ethic is a theory reached via the method of reflective equilibrium that is a coherent ordered triple set of beliefs: a set of considered moral judgments, a set of moral principles, and a set of relevant scientific background theories. The reasoning, however, can become circular and unsound when the considered moral judgments, moral principles and relevant background are not independent sources of information. If they are mixed or, for example, an intuition is mistaken for a scientific conclusion, the reasoning can be flawed.


Assuntos
Dieta/normas , Política de Saúde , Necessidades Nutricionais , Comportamento de Escolha , Ética Profissional , Liberdade , Órgãos Governamentais , Guias como Assunto , Humanos , Modelos Teóricos , Princípios Morais , Medicina Preventiva , Saúde Pública , Estados Unidos , United States Department of Agriculture
5.
Vasa ; 25(2): 142-7, 1996.
Artigo em Alemão | MEDLINE | ID: mdl-8659216

RESUMO

The Giacomini vein is present in 2.5%-10% of all patients having a phlebography because of varicosis. In a patient analysis of the last 5 years 129 patients were detected with a Giacomini vein (2.5%) out of a total of 5132 patients with varicosis. This vein was found in a significantly higher number of patients with a combined insufficiency of the long and short saphenous vein (p = 0.0001). An analysis of the different insufficiency patterns showed a Giacomini vein in 80% of insufficiency of grade I of the long and short saphenous vein. Likewise, this vein could be detected in more than half of the cases with complete insufficiency of both venous trunks (51%) as well as in 55% of the patients with a short saphenous vein insufficiency of grade III and an incomplete insufficiency of the long saphenous vein. On the other hand, there was no connection between insufficiency of the long saphenous vein, incomplete insufficiency of the short saphenous vein and the presence of the Giacomini vein. From these results we draw the conclusion that the Giacomini vein is a pathophysiologic connection between the two providing areas and thus transfers the insufficiency from one vascular system to the other. It hereby enhances the combined varicosis of both trunks as well as the formation of relapses. Therefore the Giacomini vein should always be stripped or removed by exeresis.


Assuntos
Varizes/cirurgia , Insuficiência Venosa/cirurgia , Circulação Colateral/fisiologia , Humanos , Flebografia , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/prevenção & controle , Recidiva , Estudos Retrospectivos , Fatores de Risco , Veia Safena/fisiopatologia , Veia Safena/cirurgia , Varizes/fisiopatologia , Insuficiência Venosa/fisiopatologia
7.
J Anim Sci ; 72(1): 247-53, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8138496

RESUMO

Current animal science research is dominated by disciplinary studies that are experimentally controlled and statistically analyzed. Research in animal science is also placed predominantly within a hierarchy of biological sciences ranging through molecular mechanisms, cells, organ systems, organisms, life systems, ecosystems, and human systems. In the main, disciplinary and applied animal investigations differ from each other only in that they are conducted within different biological work boundaries. Both are largely reductionist and often fragmentary. Animal science, however, has two sets of constituents, the scientific community and external interests, and both are legitimate. External interests will judge the research according to how well it contributes to a hierarchy of functional and practical knowledge instead of the biological. The functional hierarchy of inquiry ranges through validation of ideas; actions; tactics of management; strategies and systems of production; agrospheres including land and water resources, landscapes, human capital, and community; and the anthrosphere including consumers, food product chains, and global markets. More interconnection of the biological and biophysical research with functional knowledge is needed but may be limited by insufficient theoretical development of the new contributing disciplines such as molecular biology, system science, and those represented by the functional hierarchy, and recruitment of specialized scientists who often lack practical experience in agriculture and the food system. Multiple opportunities for intervention of animal agriculture exist, and multiple disciplines including the new biological and functional disciplines will be needed to provide what will be perceived to be the full scope of animal science research.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Criação de Animais Domésticos/organização & administração , Animais Domésticos , Pesquisa/organização & administração , Animais
8.
Neuropsychobiology ; 27(1): 40-5, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8515823

RESUMO

Two experiment were conducted to assess the electroencephalographic effects of (1) three different dosages of a total extract of Ginkgo biloba (EGb 761, Tebonin) and (2) three different extractions of G. biloba (Tebonin and two fractions from it). The medicament was tested against placebo using a double-blind cross-over design in 12 normal healthy males for each experiment. Medication was administered for 3 days preceding the recording sessions. 25 parameters were computed from the EEG spectra. Medication-related effects were obtained for most of the power measures, whereas dominant frequencies of the respective frequency band remained largely unchanged. The differences between the EEG effects of the two studies are critically discussed.


Assuntos
Encéfalo/efeitos dos fármacos , Eletroencefalografia/efeitos dos fármacos , Flavonoides/farmacologia , Extratos Vegetais/farmacologia , Adulto , Análise de Variância , Método Duplo-Cego , Ginkgo biloba , Humanos , Masculino
9.
Vox Sang ; 64(4): 246-7, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7685972

RESUMO

Human sera were found that contained antibody activity which caused agglutination of red cells or particles sensitized with immunoglobulin G that had first been degraded by pepsin proteolysis. The agglutinating activity was specific for a determinant that was not present on the untreated, native immunoglobulin. It was found most frequently in sera from rheumatoid arthritis patients and its titre showed some correlation with disease activity.


Assuntos
Sistema do Grupo Sanguíneo Rh-Hr , Fator Reumatoide , Epitopos , História do Século XX , Humanos
10.
Artigo em Alemão | MEDLINE | ID: mdl-1425393

RESUMO

The study was designed to examine the clinical applicability and use of computer-assisted EEG-analysis in comparison to visual EEG-analysis in patients with minor head injuries. For this in 31 patients the following examinations were performed within the first 24 hours, one, three and eight weeks after traumatization: EEG, neurological examination and standardized evaluation of subjective complaints. The EEG was analysed visually as well as computer-assisted. The results were compared to the neurological findings and subjective complaints. Reversible posttraumatic EEG-changes were observed in 50% of all patients. The results of computer-analysis and visual analysis were equivalent in respect to baseline-activity (as one of the main characteristic EEG-features). Furthermore, based on computer-assisted analysis a discriminant function is provided, which is of diagnostic and prognostic value in the single patient. We conclude that the computer-assisted EEG-analysis can be a useful alternative in EEG-routine diagnosis after minor head injuries.


Assuntos
Lesões Encefálicas/diagnóstico , Eletroencefalografia/métodos , Adolescente , Adulto , Idoso , Lesões Encefálicas/epidemiologia , Feminino , Seguimentos , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade
11.
Psychiatr Neurol Med Psychol (Leipz) ; 42(11): 649-59, 1990 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-2093195

RESUMO

The methodological requirements for the use of event-related brain potentials (ERPs) in psychiatry are critically reviewed. In particular the development of psychophysiological models is considered as essential for a functional interpretation of ERP-experiments. In addition problems of signal-analysis and clinical diagnosis relevant to ERP-research in psychiatry are briefly discussed. The logic of ERP-research in psychiatry is illustrated by a series of dichotic listening experiments.


Assuntos
Nível de Alerta/fisiologia , Córtex Cerebral/fisiopatologia , Eletroencefalografia/instrumentação , Transtornos Mentais/fisiopatologia , Tempo de Reação/fisiologia , Processamento de Sinais Assistido por Computador/instrumentação , Potenciais Evocados Auditivos/fisiologia , Humanos , Transtornos Mentais/diagnóstico , Esquizofrenia/diagnóstico , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico
12.
Electroencephalogr Clin Neurophysiol ; 75(4): 289-95, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1691077

RESUMO

The spontaneous EEG, pattern reversal VEPs, and the P300 wave were studied in patients with liver cirrhosis and early stages of hepatic encephalopathy (HE). The sensitivities of the different neurophysiological methods in the early stages of hepatic encephalopathy were compared with each other and with several neuropsychological tests. P300 latency was shown to be the most appropriate neurophysiological method for detection of early HE. The diagnostic sensitivity of the P300 latency resembled that of the number connection test (NCT). These results are discussed with regard to methodological considerations and the clinical use of both methods.


Assuntos
Encefalopatia Hepática/fisiopatologia , Adulto , Idoso , Eletroencefalografia , Potenciais Evocados Visuais/fisiologia , Feminino , Encefalopatia Hepática/diagnóstico , Humanos , Período de Latência Psicossexual , Cirrose Hepática/diagnóstico , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Neurofisiologia , Neuropsicologia , Psicometria
14.
Neurology ; 40(2): 304-8, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2132733

RESUMO

We performed positron emission tomography (PET) using 18F-labeled 2-F-2-deoxyglucose in 13 patients with systemic lupus erythematosus (SLE). Ten of them had clinical signs of central nervous system involvement (NP-SLE). All patients with neurologic symptoms showed pathologic changes on PET, always in accordance with the clinical state. Three patients without neuropsychiatric manifestations had normal PETs. Computed tomography of the brain and magnetic resonance imaging proved to be less sensitive to both presence and localization of CNS lesions. We conclude that the combination of PET and MRI constitutes the most useful diagnostic procedure for NP-SLE.


Assuntos
Encefalopatias/metabolismo , Encéfalo/metabolismo , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Transtornos Mentais/metabolismo , Tomografia Computadorizada de Emissão , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Encefalopatias/diagnóstico por imagem , Feminino , Humanos , Lúpus Eritematoso Sistêmico/metabolismo , Transtornos Mentais/diagnóstico por imagem , Pessoa de Meia-Idade
15.
Artigo em Inglês | MEDLINE | ID: mdl-18285047

RESUMO

The natural vibrational modes of axially symmetric piezoelectric ceramic disks have been calculated by the finite-element method. The disks are of the type used as active elements in compressional wave ultrasonic transducers, and are electrically polarized in thickness with full electrodes on the disk's major faces. To optimize disk geometry for ultrasonic transducer application, the dependence of the vibrational modes on the disk diameter-to-thickness ratio for ratios from 0.2 (a tall cylinder) to 10.0 (a thin disk) has been studied. Series and parallel resonance frequencies for each of the modes are determined through an eigenfrequency analysis, and effective electromechanical coupling coefficients are calculated. The modal displacement fields in the disk are calculated to determine the physical nature of each mode. An analysis of the complete spectrum of piezoelectrically active modes as a function of diameter-thickness ratio is presented for the ceramic PZT-5H, including and identification of radial, edge, length expander, thickness shear, and thickness extensional vibrations. From this analysis, optimal diameter-to-thickness ratios for good transducer performance are discussed.

18.
Angiology ; 40(7): 639-49, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2662830

RESUMO

A multicenter, prospective, placebo-controlled, double-blind trial was conducted to investigate the efficacy of intravenous infusion therapy with pentoxifylline over fourteen days in patients suffering from angiographically confirmed chronic peripheral occlusive arterial disease, Fontaine stage II, with at least a six-month history. After a washout phase of one week, the patients received in accordance with a randomization scheme either an i.v. infusion of 300 mg of pentoxifylline (15 mL ampoules) or 15 mL of a 0.9% NaCl solution in 250 mL of 5% laevulose, administered over three hours twice daily. The main efficacy parameters were treadmill-assessed initial claudication distance (ICD) and absolute claudication distance (ACD). Baseline testing revealed a mean ICD of 131 m in the pentoxifylline group and 126 m in the placebo cohort; mean ACD values were 239 m and 225 m respectively. The group of patients treated with pentoxifylline (n = 75) displayed a significantly greater improvement (p less than 0.0001) in ICD (+70%) and ACD (+60%) than the placebo group did (+33%) and 32%, respectively) (n = 79). The infusions were well tolerated in both groups.


Assuntos
Arteriopatias Oclusivas/tratamento farmacológico , Pentoxifilina/administração & dosagem , Teobromina/análogos & derivados , Adulto , Idoso , Pressão Sanguínea/efeitos dos fármacos , Ensaios Clínicos como Assunto , Método Duplo-Cego , Eletrocardiografia , Feminino , Humanos , Infusões Intravenosas , Claudicação Intermitente/tratamento farmacológico , Claudicação Intermitente/fisiopatologia , Perna (Membro)/irrigação sanguínea , Locomoção , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Pentoxifilina/efeitos adversos , Pentoxifilina/uso terapêutico , Estudos Prospectivos , Pulso Arterial/efeitos dos fármacos , Distribuição Aleatória
20.
Neuropsychobiology ; 19(3): 158-68, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3059222

RESUMO

In a double-blind placebo-controlled randomized study the influence of a cholinergic nootropic (WEB 1881 FU) on event-related brain potentials (ERPs) related to memory performance was investigated. Two different encoding modes were imposed on the subjects, who had to memorize word lists. No significant drug effects were obtained on memory performance and the ERP-concomitant of encoding, the Dm, while ERP effects related to memory were clearly present. However, the two dosages of the drug significantly influenced the overall amplitude of the late cognitive ERP components, suggesting its effect on cognitive processes.


Assuntos
Nível de Alerta/efeitos dos fármacos , Atenção/efeitos dos fármacos , Eletroencefalografia , Memória/efeitos dos fármacos , Rememoração Mental/efeitos dos fármacos , Pirrolidinonas/farmacologia , Aprendizagem Verbal/efeitos dos fármacos , Adulto , Ensaios Clínicos como Assunto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Potenciais Evocados/efeitos dos fármacos , Humanos , Masculino , Distribuição Aleatória , Retenção Psicológica/efeitos dos fármacos
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