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2.
Z Gerontol Geriatr ; 52(6): 529-536, 2019 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-31492973

RESUMO

BACKGROUND: The support of relatives living far away in terms of distance caregiving between children and their parents has gained in importance in Europe. At the same time, little is known about these care arrangements based on representative European survey data. OBJECTIVE: This article is concerned with the following questions: which statements are possible in Europe about the prevalence of persons caring for at least one parent from a geographical distance? Which forms of support are provided and which other specific socioeconomic and health-related aspects characterize these care situations? In this respect special attention is paid to differences to relatives who provide help close to their parents who are in need of care. MATERIAL AND METHODS: Data from the Survey of Health, Ageing and Retirement in Europe (SHARE) from the sixth wave of the survey in 2015 were used to perform a descriptive analysis and multivariate logistic regression. RESULTS AND CONCLUSION: The analysis showed that distance caregiving is more than a marginal phenomenon in Europe with a prevalence of 11% for a relatively close terminology (over 100 km distance between locations) and 23% for a broader terminology (over 25 km); however, the various countries are very different in terms of prevalence. The findings also point to some significant differences in terms of resources, care tasks and quality of life compared to caregivers in the same household. In light of these dynamically developing distance caregiving arrangements, this article can provide further discussion, critical reflection, and advancement to the operationalization of informal care.


Assuntos
Envelhecimento , Cuidadores , Família , Aposentadoria , Telemedicina , Criança , Europa (Continente) , Humanos , Qualidade de Vida , Inquéritos e Questionários , Telemedicina/organização & administração
3.
J Chromatogr A ; 1588: 48-57, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30591246

RESUMO

Mineral oil saturated and aromatic hydrocarbons (MOSH/MOAH) are food contaminants, mainly due migration from packaging materials made from recycled fibers, but other routes of entry into food have also been identified. Legal limits for MOSH and MOAH in food and food contact materials currently are not set, but are to be expected in the near future. For the analysis of MOSH and MOAH, the very well developed and highly automated on-line liquid chromatography-gas chromatography with flame ionization detection (LC-GC-FID) is commonly used. However, this approach is time-consuming, and data interpretation is a very challenging task. Therefore, a planar solid phase extraction (pSPE) method was developed for a rapid and efficient MOSH and MOAH screening in paper and cardboard. Based on high-performance thin-layer chromatography (HPTLC), pSPE offers the simultaneous clean-up and analysis of up to 20 samples in parallel, while MOSH and MOAH analytes were focused in two distinct target zones on silica gel HPTLC plates after a twofold development. Plate impregnation with primuline allowed the detection of MOSH by fluorescence, while MOAH were detected by UV light absorption. The pSPE screening approach provided limits of detection of 7.2 and 2.3 ng/zone for MOSH and MOAH, respectively, corresponding to 1.8 and 0.6 mg/kg paper. Coupling of pSPE with GC revealed the common MOSH and MOAH peak humps, while marker substances offered the identification of the mineral oil origin or information about recycled fiber materials. As compared to SPE-GC-FID analyses, the determined quantities of MOSH and MOAH in cardboard samples indicated pSPE as a rapid and suitable screening tool. The co-migration of polyolefin oligomeric saturated hydrocarbons, native n-alkanes, terpenes and possibly essential oils or sterol esters, however, can result in an overestimation of MOSH and MOAH. Hence, samples with pSPE results above a given limit are subsequently analyzed by GC (pSPE-GC) for confirmation and detailed evaluation.


Assuntos
Cromatografia Gasosa , Embalagem de Alimentos/normas , Inocuidade dos Alimentos/métodos , Hidrocarbonetos Aromáticos/análise , Óleo Mineral/química , Papel , Extração em Fase Sólida , Cromatografia Líquida , Contaminação de Alimentos/análise , Hidrocarbonetos Aromáticos/química , Óleo Mineral/análise , Sílica Gel/química
4.
J Gerontol B Psychol Sci Soc Sci ; 73(4): e24-e34, 2018 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-29237034

RESUMO

Objectives: The individual burden of caring for one's relatives not only depends on care characteristics but is also related to contextual factors. The objective of this study is to determine whether regional formal long-term care provision is linked to the well-being of spousal caregivers introducing the concept of "control" as central pathway to explain this link. Method: We applied multilevel analysis using data from the Survey of Health, Ageing and Retirement in Europe (SHARE) from over 29,000 Europeans and 1,800 spousal caregivers located in 138 regions in 11 countries to analyze the effects of regional contexts on caregiver well-being. The provision of formal care in a region was measured by the number of long-term care beds in nursing and residential homes among the older population. Results: We found that spousal caregivers' well-being, measured in terms of life satisfaction, loneliness, and depression, was positively linked to the regional availability of formal care, which is partly due to higher perceived control in regions with more formal care provision. Discussion: Our results suggest that formal care supply is essential not only for care recipients but also for caregivers: perceived alternatives to the private care arrangement go along with greater well-being of informal caregivers.


Assuntos
Cuidadores/psicologia , Assistência de Longa Duração/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cuidadores/estatística & dados numéricos , Depressão/epidemiologia , Depressão/psicologia , Europa (Continente)/epidemiologia , Feminino , Humanos , Solidão/psicologia , Assistência de Longa Duração/métodos , Assistência de Longa Duração/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Satisfação Pessoal , Cônjuges/psicologia , Cônjuges/estatística & dados numéricos
5.
Toxins (Basel) ; 9(9)2017 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-28872616

RESUMO

Saccharomyces cerevisiae cells are killed by zymocin, a tRNase ribotoxin complex from Kluyveromyces lactis, which cleaves anticodons and inhibits protein synthesis. Zymocin's action requires specific chemical modification of uridine bases in the anticodon wobble position (U34) by the Elongator complex (Elp1-Elp6). Hence, loss of anticodon modification in mutants lacking Elongator or related KTI (K. lactis Toxin Insensitive) genes protects against tRNA cleavage and confers resistance to the toxin. Here, we show that zymocin can be used as a tool to genetically analyse KTI12, a gene previously shown to code for an Elongator partner protein. From a kti12 mutant pool of zymocin survivors, we identify motifs in Kti12 that are functionally directly coupled to Elongator activity. In addition, shared requirement of U34 modifications for nonsense and missense tRNA suppression (SUP4; SOE1) strongly suggests that Kti12 and Elongator cooperate to assure proper tRNA functioning. We show that the Kti12 motifs are conserved in plant ortholog DRL1/ELO4 from Arabidopsis thaliana and seem to be involved in binding of cofactors (e.g., nucleotides, calmodulin). Elongator interaction defects triggered by mutations in these motifs correlate with phenotypes typical for loss of U34 modification. Thus, tRNA modification by Elongator appears to require physical contact with Kti12, and our preliminary data suggest that metabolic signals may affect proper communication between them.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas de Arabidopsis/genética , Fatores Matadores de Levedura/farmacologia , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Arabidopsis/metabolismo , RNA de Transferência/genética , RNA de Transferência/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
6.
Microb Cell Fact ; 11: 112, 2012 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-22905717

RESUMO

BACKGROUND: The Crabtree-negative yeast species Kluyveromyces lactis has been established as an attractive microbial expression system for recombinant proteins at industrial scale. Its LAC genes allow for utilization of the inexpensive sugar lactose as a sole source of carbon and energy. Lactose efficiently induces the LAC4 promoter, which can be used to drive regulated expression of heterologous genes. So far, strain manipulation of K. lactis by homologous recombination was hampered by the high rate of non-homologous end-joining. RESULTS: Selection for growth on lactose was applied to target the insertion of heterologous genes downstream of the LAC4 promoter into the K. lactis genome and found to yield high numbers of positive transformants. Concurrent reconstitution of the ß-galactosidase gene indicated the desired integration event of the expression cassette, and ß-galactosidase activity measurements were used to monitor gene expression for strain improvement and fermentation optimization. The system was particularly improved by usage of a cell lysis resistant strain, VAK367-D4, which allowed for protein accumulation in long-term fermentation. Further optimization was achieved by increased gene dosage of KlGAL4 encoding the activator of lactose and galactose metabolic genes that led to elevated transcription rates. Pilot experiments were performed with strains expressing a single-chain antibody fragment (scFvox) and a viral envelope protein (BVDV-E2), respectively. scFvox was shown to be secreted into the culture medium in an active, epitope-binding form indicating correct processing and protein folding; the E2 protein could be expressed intracellularly. Further data on the influence of protein toxicity on batch fermentation and potential post-transcriptional bottlenecks in protein accumulation were obtained. CONCLUSIONS: A novel Kluyveromyces lactis host-vector system was developed that places heterologous genes under the control of the chromosomal LAC4 promoter and that allows monitoring of its transcription rates by ß-galactosidase measurement. The procedure is rapid and efficient, and the resulting recombinant strains contain no foreign genes other than the gene of interest. The recombinant strains can be grown non-selectively in rich medium and stably maintained even when the gene product exerts protein toxicity.


Assuntos
Kluyveromyces/metabolismo , Lactase/genética , Proteínas Recombinantes/biossíntese , Biomassa , Vírus da Diarreia Viral Bovina/metabolismo , Plasmídeos/genética , Plasmídeos/metabolismo , Regiões Promotoras Genéticas , Proteínas Recombinantes/genética , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/metabolismo , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , beta-Galactosidase/genética
7.
J Mol Neurosci ; 47(3): 495-504, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22454143

RESUMO

To investigate the involvement of neurotrophins and nerve fibres in the pathogenesis of adenomyosis, we performed a retrospective, clinical study. Hysterectomy specimens from 40 patients with histologically proven adenomyosis and from 20 patients without adenomyosis or endometriosis were used for immunohistochemical analysis. In order to investigate neurotrophic properties in adenomyosis, the antibodies against nerve growth factor (NGF), neurotrophin 3 (NT-3), the high-affinity NGF receptor (TrkA), the low-affinity neurotrophin receptor (p75(NTR)), the neuronal marker S100 (for myelinated nerve fibres) and protein gene product 9.5 (PGP9.5; for intact nerve fibres) were used. There was no significant difference in the NGF, NT-3 and p75(NTR) expression in the myometrium or endometrium between the adenomyosis and the control group. The nerve fibre density (S100, PGP9.5 and p75(NTR)) did not significantly differ between the adenomyosis and control group, the nerve fibre density of the adenomyosis group was tendentially decreased when compared with the nonporous control group. The present study suggests that endometrial and uterine neurotrophin expression and endometrial innervation are not altered in adenomyosis; however, women with adenomyosis or with adenomyosis/endometriosis tendentially had less myometrial nerve fibres than the control group.


Assuntos
Adenomiose/metabolismo , Adenomiose/patologia , Fator de Crescimento Neural/metabolismo , Neurotrofina 3/metabolismo , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo , Receptor trkA/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo , Proteínas S100/metabolismo , Ubiquitina Tiolesterase/metabolismo
10.
Chembiochem ; 6(1): 86-94, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15637662

RESUMO

Semisynthetic Ras proteins are efficient probes for cell-biology experiments. With a Bodipy FL fluorophore introduced at an appropriate site on the Ras peptide by solid-phase synthesis, the resulting Ras chimera is processed by the cellular machinery and the intracellular localization of the protein can then be visualized by means of confocal laser fluorescence microscopy at relatively low concentrations. The absence of a large N-terminal protein tag overcomes possible interferences in the interaction with cellular partner proteins. The fluorescence emission from Bodipy FL is continuous and disappears only after irreversible bleaching. These characteristics make Ras proteins with nonprotein fluorophores suitable for biophysical analysis. The easy accessibility of the lipopeptide moiety by chemical synthesis opens up numerous options for further biological investigations.


Assuntos
Corantes Fluorescentes/química , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Proteínas ras/química , Sequência de Aminoácidos , Animais , Células Cultivadas , Corantes Fluorescentes/análise , Corantes Fluorescentes/síntese química , Dados de Sequência Molecular , Proteínas ras/análise , Proteínas ras/síntese química
11.
Methods Mol Biol ; 283: 245-54, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15197316

RESUMO

Chemically synthesized truncated Ras proteins are coupled to C-terminal Ras peptides via a maleimidocaproyl linker. The resulting product is isolated by extraction with Triton X-114. The biological activity of these oncogenic Ras lipoproteins can be determined in a cell-based differentiation assay by microinjection into PC12 cells.


Assuntos
Lipoproteínas/síntese química , Proteínas ras/química , Animais , Bioensaio/métodos , Diferenciação Celular , Lipoproteínas/química , Microinjeções , Células PC12 , Ratos , Proteínas Recombinantes/biossíntese , Proteínas ras/biossíntese
12.
Proc Natl Acad Sci U S A ; 101(23): 8531-6, 2004 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-15163793

RESUMO

The Hedgehog proteins are potent organizers of animal development. They carry a cholesterol ester at the C terminus of their signaling domain. The membrane anchoring mediated by this lipophilic modification was studied by means of an approach integrating cell biology, biochemistry, biophysics, and organic chemistry techniques. Sterol-modified and fluorescent-labeled Hedgehog-derived peptides and proteins were synthesized and investigated in biophysical and cell-biological assays. These experiments revealed that cholesterol alone anchors proteins to membranes with significant strength and half-times for spontaneous desorption of several hours. Its membrane anchoring ability is comparable to dual lipidation motifs such as double geranylgeranylation or S-palmitoylation plus S-farnesylation found in other lipidated proteins. The experiments also demonstrate that membrane binding changes dramatically if short lipidated peptides are equipped with a large protein. These data suggest that for Hedgehog release and subsequent signaling an interaction partner such as the Dispatched protein is necessary. In addition to these findings the described approach allows one to correlate biophysical data obtained with model peptides with data determined with fully functional proteins and to combine results from in vitro and in vivo experiments. It should be generally applicable to other membrane anchors and proteins.


Assuntos
Colesterol/metabolismo , Proteínas de Drosophila/química , Proteínas de Drosophila/metabolismo , Animais , Proteínas Hedgehog , Técnicas In Vitro , Lipídeos de Membrana/metabolismo , Microdomínios da Membrana/química , Microdomínios da Membrana/metabolismo , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Células PC12 , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Ligação Proteica , Ratos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas ras/química , Proteínas ras/metabolismo
14.
J Am Chem Soc ; 125(42): 12749-58, 2003 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-14558822

RESUMO

A modular strategy for the assembly of farnesylated N-Ras heptapeptides carrying a photoactivatable benzophenone (BP) group within the lipid residue is described. This strategy is based on the fragment condensation of a N-terminal hexapeptide synthesized on the solid support with a cysteine methyl ester which is modified with different farnesyl analogues, incorporating the photophor. At the N-terminus of the peptides different functional groups can be attached, e.g., biotin for product enrichment and detection after photoactivation or a maleimido (MIC) linker, allowing for the coupling to proteins carrying a C-terminal free cysteine. Using this strategy, 24 peptides were synthesized, incorporating farnesyl analogues with four different chain lengths. Two of these photoactivatable conjugates were ligated to oncogenic human N-RasG12V Delta 181. A cellular transformation assay revealed that the semisynthetic proteins retain their biological activity despite the photolabel. The first photolabeling experiments with a geranyl-BP-labeled N-Ras construct and the farnesyl-sensitive guanine nucleotide exchange factor hSos1 indicate that this photoaffinity labeling system can be particularly useful for studying protein-protein interactions, e.g., the participation of the farnesyl group in Ras signaling, which is still discussed with controversy.


Assuntos
Fragmentos de Peptídeos/síntese química , Proteínas ras/síntese química , Animais , Benzofenonas/síntese química , Benzofenonas/química , Cisteína/análogos & derivados , Cisteína/química , Oligopeptídeos/síntese química , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Células PC12 , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Fotoquímica , Ratos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Proteínas ras/química , Proteínas ras/farmacologia
15.
Naturwissenschaften ; 89(9): 381-90, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12435088

RESUMO

We have developed a basic concept for studying cell biological phenomena using an interdisciplinary approach starting from organic chemistry. Based on structural information available for a given biological phenomenon, unsolved chemical problems are identified. For their solution, new synthetic pathways and methods are developed, which reflect the state of the art in synthesising lipidated peptide conjugates. These compounds are used as molecular probes for the investigation of biological phenomena that involve both the determination of biophysical properties and cell biological studies. The interplay between organic synthesis, biophysics and cell biology in the study of protein lipidation may open up new and alternative opportunities to gain knowledge about the biological phenomenon that could not be obtained by employing biological techniques alone. This fruitful combination is highlighted using the Ras protein as an outstanding example. Included herein is: the development of methods for the synthesis of Ras-derived peptides and fully functional Ras proteins, the determination of the biophysical properties, in particular the ability to bind to model membranes, and finally the use of synthetic Ras peptides and proteins in cell biological experiments.


Assuntos
Biologia , Química Orgânica , Lipoproteínas/síntese química , Sequência de Aminoácidos , Ácidos Carboxílicos , Lipoproteínas/metabolismo , Fenômenos de Química Orgânica , Peptídeos/síntese química , Peptídeos/metabolismo , Conformação Proteica , Proteínas ras
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