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1.
Oncogene ; 36(15): 2146-2159, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27721410

RESUMO

Deregulation of mitotic microtubule (MT) dynamics results in defective spindle assembly and chromosome missegregation, leading further to chromosome instability, a hallmark of tumor cells. RBP-J interacting and tubulin-associated protein (RITA) has been identified as a negative regulator of the Notch signaling pathway. Intriguingly, deregulated RITA is involved in primary hepatocellular carcinoma and other malignant entities. We were interested in the potential molecular mechanisms behind its involvement. We show here that RITA binds to tubulin and localizes to various mitotic MT structures. RITA coats MTs and affects their structures in vitro as well as in vivo. Tumor cell lines deficient of RITA display increased acetylated α-tubulin, enhanced MT stability and reduced MT dynamics, accompanied by multiple mitotic defects, including chromosome misalignment and segregation errors. Re-expression of wild-type RITA, but not RITA Δtub ineffectively binding to tubulin, restores the phenotypes, suggesting that the role of RITA in MT modulation is mediated via its interaction with tubulin. Mechanistically, RITA interacts with tubulin/histone deacetylase 6 (HDAC6) and its suppression decreases the binding of the deacetylase HDAC6 to tubulin/MTs. Furthermore, the mitotic defects and increased MT stability are also observed in RITA-/- mouse embryonic fibroblasts. RITA has thus a novel role in modulating MT dynamics and its deregulation results in erroneous chromosome segregation, one of the major reasons for chromosome instability in tumor cells.


Assuntos
Proteínas de Ligação a DNA/deficiência , Microtúbulos/metabolismo , Proteínas de Neoplasias/deficiência , Acetilação , Animais , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/metabolismo , Células HCT116 , Células HeLa , Desacetilase 6 de Histona , Histona Desacetilases/metabolismo , Humanos , Células MCF-7 , Camundongos , Camundongos Knockout , Mitose/fisiologia , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/metabolismo , Fuso Acromático/metabolismo , Tubulina (Proteína)/metabolismo
2.
Aging Ment Health ; 8(1): 83-91, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14690872

RESUMO

Congestive heart failure (CHF) lowers survival and worsens the quality of life (QOL) of over four million older Americans. Both clinicians and standardized instruments used to assess the QOL of patients with CHF focus primarily on physical symptoms rather than capturing the full range of psychosocial concerns. The purpose of this study was to gather descriptions of the components of QOL as understood by patients living with CHF. Focus groups were conducted with patients with known CHF, New York Heart Association (NYHA) class I-IV, and left ventricular fraction of <40%. Focus groups were audiotaped, transcribed, and reviewed for common and recurrent themes using the methods of constant comparisons. We conducted three focus groups (n = 15) stratified by NYHA stage with male patients ranging in age from 47-82 years of age. Five patients were classified with NYHA stage III/IV and ten with NYHA stage I/II. Thirty attributes of QOL were identified which fell into five broad domains: symptoms, role loss, affective response, coping, and social support. Expectedly, patients reported the importance of physical symptoms; however, participants also identified concern for family, the uncertainty of prognosis, and cognitive function as dimensions of QOL. Changes in patients' lives attributed to CHF were not always considered deficiencies; rather, methods of coping with CHF were identified as important attributes representing possible opportunities for personal growth. Clinicians must understand the full range of concerns affecting the QOL of their older patients with CHF. The findings suggest that psychosocial aspects and patient uncertainty about their prognosis are important components of QOL among CHF patients.


Assuntos
Atividades Cotidianas/psicologia , Insuficiência Cardíaca/psicologia , Qualidade de Vida/psicologia , Papel do Doente , Ajustamento Social , Disfunção Ventricular Esquerda/psicologia , Adaptação Psicológica , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Grupos Focais , Identidade de Gênero , Avaliação Geriátrica , Humanos , Masculino , Pessoa de Meia-Idade , North Carolina , Autocuidado/psicologia , Apoio Social
3.
J Pain Symptom Manage ; 22(3): 727-37, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11532586

RESUMO

To examine patients', families', and health care providers' preferences regarding preparation for the end of life, attributes of preparation were generated in qualitative focus group discussions and subsequently tested for generalizability in a quantitative national survey. Respondents from all groups showed consensus on the importance of naming someone to make decisions, knowing what to expect about one's physical condition, having financial affairs in order, having treatment preferences in writing, and knowing that one's physician is comfortable talking about death and dying. Patients were more likely than physicians to want to plan funerals and know the timing of death and less likely than all other groups to want to discuss personal fears. Participants in care of dying patients agree overwhelmingly with the importance of preparation. However, significant barriers to preparation impede it from being a common part of clinical encounters. Further research and training are needed to ensure that the desire for greater preparation is translated into improved action toward preparation in medical practice.


Assuntos
Cuidadores/psicologia , Família/psicologia , Satisfação do Paciente , Pacientes/psicologia , Médicos/psicologia , Assistência Terminal/psicologia , Adulto , Idoso , Atitude Frente a Morte , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade da Assistência à Saúde
4.
Environ Sci Pollut Res Int ; 8(3): 222-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11505907

RESUMO

The principles of precaution and sustainability require more consideration in the assessment of environmental risks posed by chemicals and genetically modified organisms. Instead of applying risk reduction measures when there are serious indications for damage, full scientific certainty is often waited for before taking action. The precautionary principle particularly should be applied in those cases in which the extent and probability of damage are uncertain, e.g. in the case of persistent chemicals which are additionally bioaccumulative or highly mobile. Based on these principles, environmental action targets for risks associated with GMOs and chemicals can be developed. Risk management not only includes statutory measures but also instruments designed to influence behaviour indirectly are important to achieve the goals. Particularly for risks of GMOs which provoke fear, risk communication is important. Some rules to which attention should be paid in communication with the public are presented.


Assuntos
Monitoramento Ambiental , Engenharia Genética , Animais , Comunicação , Poluentes Ambientais , Humanos , Saúde Pública , Medição de Risco
5.
Environ Sci Pollut Res Int ; 8(2): 120-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11400637

RESUMO

Risks can be characterised by several parameters. A risk is commonly defined to be the product of the extent of damage and the probability of its occurrence. But there are several other characteristics to be taken into account: degree of certainty in determining extent and probability, persistency, ubiquity, irreversibility, delay effect and mobilisation potential. As potential risks of genetically modified plants (GMPs), resistance to antibiotics, impact on non-target organisms, spread of genes and GMOs, and secondary consequences, e.g. on cultivation practice, are discussed in detail. Risks of GMPs are, in general, characterised by high uncertainty of the magnitude and probability of damage, a high mobilisation potential and a delay effect.


Assuntos
Poluentes Ambientais/efeitos adversos , Plantas Geneticamente Modificadas/efeitos adversos , Poluição Ambiental/efeitos adversos , Poluição Ambiental/legislação & jurisprudência , Humanos , Medição de Risco/legislação & jurisprudência , Medição de Risco/métodos , Gestão de Riscos/métodos
6.
Protein Expr Purif ; 21(1): 220-3, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11162409

RESUMO

The isolation of recombinant proteins from bacterial or eukaryotic systems often requires a laborious optimization of expression and purification conditions. To greatly facilitate this procedure we included the green fluorescent protein (GFP) in bacterial expression vectors. This approach allowed us to sensitively detect the GFP hybrid proteins already in intact bacterial cells using a fluorescence microscope. To rapidly analyze a variety of conditions essential for protein expression, the GFP signal, indicative of expression levels, was directly quantitated in live bacterial suspensions using a fluorescence plate reader. Thus, GFP tagging not only allows one to directly monitor protein expression in general but also appears to increase protein stability or solubility.


Assuntos
Glutationa Transferase/genética , Proteínas Luminescentes , Proteínas Recombinantes de Fusão/biossíntese , Clonagem Molecular , Escherichia coli/citologia , Escherichia coli/enzimologia , Escherichia coli/crescimento & desenvolvimento , Genes Reporter , Glutationa Transferase/isolamento & purificação , Glutationa Transferase/metabolismo , Proteínas de Fluorescência Verde , Humanos , Proteínas Luminescentes/análise , Proteínas Luminescentes/isolamento & purificação , Microscopia de Fluorescência , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/isolamento & purificação , Transglutaminases/análise , Transglutaminases/genética
7.
JAMA ; 284(19): 2476-82, 2000 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11074777

RESUMO

CONTEXT: A clear understanding of what patients, families, and health care practitioners view as important at the end of life is integral to the success of improving care of dying patients. Empirical evidence defining such factors, however, is lacking. OBJECTIVE: To determine the factors considered important at the end of life by patients, their families, physicians, and other care providers. DESIGN AND SETTING: Cross-sectional, stratified random national survey conducted in March-August 1999. PARTICIPANTS: Seriously ill patients (n = 340), recently bereaved family (n = 332), physicians (n = 361), and other care providers (nurses, social workers, chaplains, and hospice volunteers; n = 429). MAIN OUTCOME MEASURES: Importance of 44 attributes of quality at the end of life (5-point scale) and rankings of 9 major attributes, compared in the 4 groups. RESULTS: Twenty-six items consistently were rated as being important (>70% responding that item is important) across all 4 groups, including pain and symptom management, preparation for death, achieving a sense of completion, decisions about treatment preferences, and being treated as a "whole person." Eight items received strong importance ratings from patients but less from physicians (P<.001), including being mentally aware, having funeral arrangements planned, not being a burden, helping others, and coming to peace with God. Ten items had broad variation within as well as among the 4 groups, including decisions about life-sustaining treatments, dying at home, and talking about the meaning of death. Participants ranked freedom from pain most important and dying at home least important among 9 major attributes. CONCLUSIONS: Although pain and symptom management, communication with one's physician, preparation for death, and the opportunity to achieve a sense of completion are important to most, other factors important to quality at the end of life differ by role and by individual. Efforts to evaluate and improve patients' and families' experiences at the end of life must account for diverse perceptions of quality. JAMA. 2000;284:2476-2482.


Assuntos
Atitude Frente a Morte , Cuidadores/psicologia , Família/psicologia , Pacientes/psicologia , Médicos/psicologia , Qualidade de Vida , Assistência Terminal , Idoso , Estudos Transversais , Coleta de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Análise de Regressão , Doente Terminal , Estados Unidos
8.
Hosp J ; 15(1): 35-51, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11033658

RESUMO

Although the pursuit of Medicare certification has been one of the most controversial events in hospice history no study has examined its impact using data from a defined population of hospices before, during, and after federal legislation was enacted. This paper revisits the debate over the changing role of volunteers using such a longitudinal data source. Over time, as the patient population grew, aggregate levels of volunteers and professional staff increased. However, the ratios of professional staff and volunteers to patients reveal that regardless of certification status, hospices retained more professional staff per patient and fewer volunteers per patient over time. These data suggest hospices, particularly certified organizations, have transitioned from voluntary organizations to professionally staffed organizations with a strong volunteer component. The most important issue for future research is whether the observed changes have affected the quality of hospice care.


Assuntos
Acreditação/legislação & jurisprudência , Hospitais para Doentes Terminais , Medicare/legislação & jurisprudência , Recursos Humanos de Enfermagem/provisão & distribuição , Admissão e Escalonamento de Pessoal/organização & administração , Voluntários , Hospitais para Doentes Terminais/legislação & jurisprudência , Hospitais para Doentes Terminais/tendências , Humanos , Estudos Longitudinais , North Carolina , Recursos Humanos de Enfermagem/tendências , Inovação Organizacional , Estudos Retrospectivos , Estados Unidos , Voluntários/estatística & dados numéricos , Recursos Humanos
9.
Ann Intern Med ; 132(10): 825-32, 2000 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-10819707

RESUMO

Despite a recent increase in the attention given to improving end-of-life care, our understanding of what constitutes a good death is surprisingly lacking. The purpose of this study was to gather descriptions of the components of a good death from patients, families, and providers through focus group discussions and in-depth interviews. Seventy-five participants-including physicians, nurses, social workers, chaplains, hospice volunteers, patients, and recently bereaved family members-were recruited from a university medical center, a Veterans Affairs medical center, and a community hospice. Participants identified six major components of a good death: pain and symptom management, clear decision making, preparation for death, completion, contributing to others, and affirmation of the whole person. The six themes are process-oriented attributes of a good death, and each has biomedical, psychological, social, and spiritual components. Physicians' discussions of a good death differed greatly from those of other groups. Physicians offered the most biomedical perspective, and patients, families, and other health care professionals defined a broad range of attributes integral to the quality of dying. Although there is no "right" way to die, these six themes may be used as a framework for understanding what participants tend to value at the end of life. Biomedical care is critical, but it is only a point of departure toward total end-of-life care. For patients and families, psychosocial and spiritual issues are as important as physiologic concerns.


Assuntos
Atitude Frente a Morte , Família/psicologia , Pessoal de Saúde/psicologia , Pacientes/psicologia , Assistência Terminal , Adulto , Planejamento Antecipado de Cuidados , Idoso , Tomada de Decisões , Feminino , Grupos Focais , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Dor/prevenção & controle , Pesquisa Qualitativa , Pesquisa
10.
Regul Toxicol Pharmacol ; 31(1): 1-12, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10715219

RESUMO

Accidental spills resulting in severe pollution can occur during transportation or handling of large volumes of chemicals. To address this problem, chemicals are classified according to the level of hazard to man and the environment in order to then define graduated technical standards. Three regulatory examples (enforced or drafted for transport and industrial installations in Europe) covering aspects of limnic as well as sea water are discussed in regard to health aspects of pollution. Whereas for the safety of seagoing tankships an exposure orientated combination of health and environmental aspects is used, for industrial plants in Germany a scoring system based on the European Union's Risk Phrase system is applied. The health-related parameters primarily used for hazard classification are repeated-dose toxicity and acute oral and dermal toxicity. Acute oral toxicity is most widely used because of the ready availability of data. Carcinogenicity is treated as the most important hazard. The report discusses the importance of dermal exposure, aspiration, and endocrine disruption as parameters as well as the importance of health criteria for the protection of aquatic organisms.


Assuntos
Medição de Risco/estatística & dados numéricos , Gestão da Segurança/legislação & jurisprudência , Poluentes Químicos da Água/toxicidade , Animais , Carcinógenos/classificação , Carcinógenos/toxicidade , União Europeia , Contaminação de Alimentos/análise , Humanos , Gestão da Segurança/estatística & dados numéricos , Teratogênicos/classificação , Teratogênicos/toxicidade , Meios de Transporte , Poluentes Químicos da Água/classificação
11.
Soc Sci Med ; 38(7): 925-36, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8202741

RESUMO

The inconclusive debate about Fries' theory of "natural death and the compression of morbidity" has diverted attention from two key issues--the modifiability and related dynamics of functional impairment in late adulthood. Evidence is presented from a large (N = 11,000) panel of adults aged initially 58-63 over the period of a decade which documents substantial modification of functional status. Further, patterned changes in functional status are related to the dynamics of income, historically a major determinant of functional status, and independently to educational attainment. The dynamics of functional status, of income, and of their relationship are explored using discrete time hazard models in an event history analysis incorporating time-varying income and functional status indicators. The importance of income and of education as positive, independent predictors of functional status and patterned changes of functional status is confirmed. The implications of this finding for differentiating distal (e.g. education) and proximate (e.g. income) measures of socioeconomic status and for assessing competing theories of social causation and social selection are discussed.


Assuntos
Envelhecimento/fisiologia , Idoso Fragilizado , Idoso , Escolaridade , Feminino , Humanos , Renda , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Razão de Chances , Fatores Socioeconômicos
15.
Am J Hosp Pharm ; 48(11): 2383, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1746567
17.
Eur J Biochem ; 173(1): 233-9, 1988 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-3281833

RESUMO

The procedures developed earlier (Friedrich and Woolley, preceding paper in this journal) for probing electrostatic potential with the fluorescein label were applied to transfer RNA. By using tRNA species that contain chemically reactive bases we were able to label these bases with fluorescein derivatives and thus to 'map' the electrostatic potential around the molecule. Both the electrostatic potential and the fluorescence emission anisotropy data that were obtained at the same time could be understood in terms of the well-known, paradigmatic crystal structure of tRNA(Phe). However, within the distribution of the various tRNA species, tRNA(Met)f appeared to occupy an extreme position, which suggests a relation between the conformation in solution and the initiation function of this molecule. Comparison with theoretical predictions by others of the electrostatic potential map of tRNA showed agreement in respect of trends, but the values of the potentials measured were orders of magnitude lower than predicted. This we attribute primarily to solvation.


Assuntos
Fluoresceínas , RNA de Transferência Aminoácido-Específico , Eletroquímica , Escherichia coli , Concentração de Íons de Hidrogênio , Cinética , Substâncias Macromoleculares , Magnésio , Ligação Proteica , Conformação Proteica , RNA de Transferência Aminoácido-Específico/metabolismo , Espectrometria de Fluorescência/normas
18.
Eur Biophys J ; 16(1): 45-51, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3396517

RESUMO

Using the technique of singlet-singlet (Förster-type) resonance energy transfer, we have determined five distances in the programmed ribosome, either with the P site or with both the A and the P sites occupied. Two of the distances are new and two agree with earlier measurements; the fifth showed disagreement in detail with earlier results of others, but a consistent general trend. The distances substantiate a current model for the location of ribosomally bound tRNA, except in regard of the position of the 3' end of P-site tRNA, which seems according to our results to lie too far away from the 3' terminus of the 16 S RNA to be accommodated in the model. We present new evidence for the hypothesis that anomalously charged tRNA does not bind to the cognately programmed A site in the same way as does tRNA charged with an amino acid. Occupation of the A site restricts mobility of the 3' end of tRNA in the P site.


Assuntos
RNA de Transferência/análise , Ribossomos/análise , Transferência de Energia , Fluorometria
19.
Biophys Chem ; 26(2-3): 367-74, 1987 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-17010285

RESUMO

The general case of Förster-type energy transfer is that in which energy is exchanged in both directions between two unlike fluorophores. In such cases, energy is transferred from the conventionally defined donor to the conventionally defined acceptor (forward transfer) and at the same time from the acceptor to the donor (reverse transfer). Expressions are derived to describe the fluorescence intensities and lifetimes of fluorophores undergoing simultaneous forward and reverse transfer; these are compared with corresponding quantities for the case more usually considered, in which only forward transfer is significant. It is shown that the presence of reverse transfer removes the distinction between donor and acceptor, and allows such anomalous effects as 'acceptor quenching'. A confirmatory example is described. It is shown that the equations generally used in distance determination by steady-state fluorescence spectroscopy can also be applied in the presence of reverse transfer, if a correction term is included; however, for lifetime spectroscopy the correction is more complex.

20.
Phys Rev Lett ; 54(18): 1969-1972, 1985 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-10031189
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