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1.
Biomed Tech (Berl) ; 64(s1): 69-71, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30753138
2.
J Biotechnol ; 284: 75-83, 2018 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-30110597

RESUMO

Recently it has been proposed to use sensors based on genetically engineered reporter cells to perform continuous online water monitoring. Here we describe the design, assembly and performance of a novel flow-through device with immobilized genetically modified yeast cells that produce a fluorescent protein upon stimulation with diclofenac whose intensity is then detected by fluorescence microscopy. Although other devices employing immobilized cells for the detection of various analytes have already been described before, as novelty our system allows safe enclosure of the sensor cells, and thus, to obtain fluorescent signals that are not falsified by a loss of cells. Furthermore, the yeast cells are prevented from being released into the environment. Despite the safe containment, the immobilized reporter cells are accessible to nutrients and analytes. They thus have both the ability to grow and respond to the analyte. Both in cell culture medium and standardized synthetic wastewater, we are able to differentiate between diclofenac concentrations in a range from 10 to 100 µM. As particularly interesting feature, we show that only the biologically active fraction of diclofenac is detected. Nowadays, contamination of wastewater with diclofenac and other pharmaceutical residues is becoming a severe problem. Our investigations may pave the way for an easy-to-use and cost-efficient wastewater monitoring method.


Assuntos
Anti-Inflamatórios não Esteroides/análise , Técnicas Biossensoriais , Diclofenaco/análise , Proteínas de Fluorescência Verde/metabolismo , Saccharomyces cerevisiae/metabolismo , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Células Imobilizadas/metabolismo , Proteínas de Fluorescência Verde/genética , Dispositivos Lab-On-A-Chip , Saccharomyces cerevisiae/genética
3.
B-ENT ; 12(1): 59-65, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27097395

RESUMO

OBJECTIVES: Somatic tinnitus originates from increased activity of the dorsal cochlear nucleus, a cross-point between the somatic and auditory systems. Its activity can be modified by auditory stimulation or somatic system manipulation. Thus, sound enrichment and white noise stimulation might decrease tinnitus and associated somatic symptoms. The present uncontrolled study sought to determine somatic tinnitus prevalence among tinnitus sufferers, and to investigate whether sound therapy with counselling (tinnitus retraining therapy; TRT) may decrease tinnitus-associated somatic symptoms. METHODS: To determine somatic tinnitus prevalence, 70 patients following the TRT protocol completed the Jastreboff Structured Interview (JSI) with additional questions regarding the presence and type of somatic symptoms. Among 21 somatic tinnitus patients, we further investigated the effects of TRT on tinnitus-associated facial dysesthesia. Before and after three months of TRT, tinnitus severity was evaluated using the Tinnitus Handicap Inventory (THI), and facial dysesthesia was assessed with an extended JSI-based questionnaire. RESULTS: Among the evaluated tinnitus patients, 56% presented somatic tinnitus-including 51% with facial dysesthesia, 36% who could modulate tinnitus by head and neck movements, and 13% with both conditions. Self-evaluation indicated that TRT significantly improved tinnitus and facial dysesthesia in 76% of patients. Three months of TRT led to a 50% decrease in mean THI and JSI scores regarding facial dysesthesia. CONCLUSIONS: Somatic tinnitus is a frequent and underestimated condition. We suggest an extension of the JSI, including specific questions regarding somatic tinnitus. TRT significantly improved tinnitus and accompanying facial dysesthesia, and could be a useful somatic tinnitus treatment.


Assuntos
Estimulação Acústica/métodos , Doenças do Nervo Facial/epidemiologia , Parestesia/epidemiologia , Zumbido/epidemiologia , Adulto , Idoso , Núcleo Coclear , Aconselhamento , Doenças do Nervo Facial/reabilitação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Parestesia/reabilitação , Zumbido/reabilitação
4.
Public Health ; 131: 40-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26718421

RESUMO

OBJECTIVES: Stakeholders involved in community dementia support services often work on their own and without coordination with other services. These circumstances can result in a lack of information and support for people with dementia and their family caregivers at home. To increase the coordination between existing support services, so-called 'Dementia Care Networks' (DCNs) have been established. Most of the tasks that are performed in DCNs are based on communication strategies. Therefore, knowledge management (KM) is a key process in these networks. However, few studies have focused on this topic. This study attempted to evaluate KM strategies in DCNs across Germany as part of the DemNet-D study. STUDY DESIGN: A qualitative interview study design was used. METHODS: Qualitative data were collected during single and group interviews with key persons associated with thirteen DCNs. Interviews were audiotaped and transcribed, and a structured content analysis was conducted. The framework for the analysis was derived from a KM model. RESULTS: Information dissemination strategies for people with dementia and their informal caregivers based on actively established contacts appear to be more successful than passive strategies. General practitioners often play a key role as external gatekeepers in initiating contact between a network and a person affected by dementia. In this context, case managers can help integrate external stakeholders, such as general practitioners or pharmacists, into DCNs using different KM strategies. The systematic development of common objectives under an agency-neutral leadership seems to be an important aspect of successful KM within DCNs. CONCLUSIONS: The findings reported here can help DCNs optimize their KM strategies for generating tailored information and support services for people with dementia living at home and their family caregivers. In particular, the identified potential knowledge distribution barriers and facilitators will be of practical use to DCN stakeholders.


Assuntos
Redes Comunitárias/organização & administração , Demência/terapia , Gestão do Conhecimento , Idoso , Cuidadores/psicologia , Demência/psicologia , Alemanha , Humanos , Disseminação de Informação , Pesquisa Qualitativa , Características de Residência/estatística & dados numéricos , Apoio Social
5.
B-ENT ; Suppl 26(1): 155-171, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29461740

RESUMO

Acute external ear lesions: clinical aspects, assessment and management. We reviewed the literature concerning the assessment and the management of the external ear traumas, which is not very rich. Nevertheless, we outlined the practical attitudes in the four major conditions met: the auricular haematoma, the auricular perichondritis, the auricular laceration and auricular bums. All these pathologies must be promptly treated because there is a risk of perichondritis, which can destroy the cartilage and will result in a severely deformed ear. Auricular haematomas must be drained as soon as possible, lacerations with exposed cartilage must be stitched urgently, and burnt ears should be washed, coated with alginates (Flaminal@) and covered with a loose dressing. Antibioprophyl- axy should always be prescribed after a complete microbiological sampling.


Assuntos
Alginatos/uso terapêutico , Antibacterianos/uso terapêutico , Bandagens , Queimaduras/terapia , Pavilhão Auricular/lesões , Glucose Oxidase/uso terapêutico , Hematoma/terapia , Lacerações/terapia , Lactoperoxidase/uso terapêutico , Polietilenoglicóis/uso terapêutico , Irrigação Terapêutica , Combinação de Medicamentos , Orelha Externa/lesões , Humanos , Técnicas de Sutura
6.
J Nutr Health Aging ; 18(9): 787-91, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25389955

RESUMO

OBJECTIVES: We compared the nutritional status of elderly people living in two different settings (shared-housing arrangements and home-living arrangements). DESIGN: For this secondary analysis, a cross-sectional study was performed. SETTING: For the home-living setting, home-dwelling elderly people from Hamburg, Germany who were participants in a prior study were included. For the shared-housing arrangements (SHA) setting, we used baseline data from the WGQual Study. PARTICIPANTS: The sample from the home-living setting comprised patients who were discharged from a geriatric rehabilitation clinic within the six months prior to data collection. The sample from the shared-housing arrangements comprised all residents that lived in SHAs. MEASUREMENTS: Nutritional status was examined by administering the Mini Nutritional Assessment (MNA). Cognitive status was measured by the Mini Mental State Examination (MMSE). RESULTS: Overall, 142 individuals participated in this study. Statistical analysis showed differences in both overall MNA scores and MNA assessment scores. Significantly more participants from the SHA setting were at risk of malnutrition compared to the home-living setting. CONCLUSION: Screening and assessment of nutritional status and prevention interventions should be considered in SHA settings.


Assuntos
Estado Nutricional , Características de Residência/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Berlim/epidemiologia , Estudos Transversais , Feminino , Avaliação Geriátrica , Instituição de Longa Permanência para Idosos/estatística & dados numéricos , Humanos , Masculino , Desnutrição/epidemiologia , Avaliação Nutricional , Populações Vulneráveis/estatística & dados numéricos
7.
Rehabilitation (Stuttg) ; 53 Suppl 1: S4-S43, 2014 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-24474000

RESUMO

BACKGROUND: In Germany, people with multiple severe disabilities caused by brain injuries, are predominantly cared for in permanent residential living facilities. In 2009 the Fürst Donnersmarck Foundation (FDSt) launched a new housing project - supported living accommodations (SLA) - for this group of people. Residents from a permanent residential living facility (Fürst Donnersmarck House, FDH) are offered the opportunity to move into 2 newly built SLA with a 24/7 individual support of a social pedagogic staffs as well as nursing care. The aim of the study is to compare the changes of residents' social and health related outcomes in the SLA group as compared to the group remaining in stationary care. METHODS: In a prospective longitudinal study (2009-2011) residents of the FDH are surveyed using standardized self- and proxy-rating instruments. Times of measurement are shortly before moving into the SLA (baseline, t1) and at follow-up after 6, 12 and 18 months after relocation (t2-t4). Additionally to residents' socio-demographic data, health outcomes including ADL functioning (EBI), quality of life (WHOQoL-Bref, EQ-5D), need of assistance (HMB-W), social inclusion/perceived disability (WHODAS II), anxiety and depression (HADS) and social contacts were evaluated. RESULTS: 40 residents could be included into the study, 29 of them moved into 2 SLA. The underlying neurological causes of the handicap were mainly sequelae of acuired damage of the central nervous system during adult age. Residents are on average 46.2 years old and predominantly male (65%). During the study the perceived dis-ability (WHODAS II) increased statistically significant but we could not show differences between groups (p > 0.05). Changes in functional and cognitive everyday abilities, fear, depression and quality of life (WHOQoL-Bref, EQ-5D) could not be shown (p > 0.05). The perceived sense of -mastery (Pearlin Mastery Scale) increased statistically significant and showed more positive developments by tendency in SLA. Everyday activities in SLA increased to a large extent. CONCLUSION: Some positive but no overall effects of moving into SLA can be shown. It is remarkable that the serious changes of living conditions do not lead to less QoL or more anxiety in this vulnerable group of people but resulted in increasing external contacts and greater mobility. Social pedagogic support offers the residents the chance to bear a more self-determined life and to participate actively in new social networks.


Assuntos
Lesões Encefálicas/reabilitação , Cuidados Críticos/estatística & dados numéricos , Pessoas com Deficiência/reabilitação , Pessoas com Deficiência/estatística & dados numéricos , Serviços de Assistência Domiciliar/estatística & dados numéricos , Vida Independente/estatística & dados numéricos , Assistência de Longa Duração/estatística & dados numéricos , Atividades Cotidianas , Distribuição por Idade , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Programas e Projetos de Saúde , Índice de Gravidade de Doença , Distribuição por Sexo , Apoio Social , Resultado do Tratamento
8.
Z Gerontol Geriatr ; 47(7): 583-9, 2014 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-23912130

RESUMO

BACKGROUND: Since the mid-1990s, supervised shared-housing arrangements (SHA; assisted living facilities) have developed as a specific type of small-scale living facility for elderly care-dependent persons with dementia in Germany, offering services different than those in residential care. Neither a uniform and binding definition of SHA nor reliable estimates concerning numbers currently exist. Since January 2013, SHA have been promoted nationwide in Germany by law. MATERIALS AND METHODS: In a cross-sectional study funded by the National Association of Statutory Health Insurance Funds numbers as well as legal and financial frameworks of SHA in Germany were surveyed. RESULTS: As of February 2013, almost all German "Bundesländer" (federal states) have created special legal regulations for supervised SHA. The results of the present study show at least 1,420 SHA with 10,590 care places for adults in Germany. The regional distribution differs greatly. CONCLUSION: Supervised SHA are increasingly an established care offer among the various long-term care offers in Germany. Different care and support offers help ensure individualized and high quality care for elderly care-dependent persons with dementia.


Assuntos
Moradias Assistidas/legislação & jurisprudência , Moradias Assistidas/provisão & distribuição , Demência/enfermagem , Serviços de Saúde para Idosos/legislação & jurisprudência , Serviços de Saúde para Idosos/provisão & distribuição , Instituição de Longa Permanência para Idosos/legislação & jurisprudência , Instituição de Longa Permanência para Idosos/provisão & distribuição , Idoso , Idoso de 80 Anos ou mais , Demência/epidemiologia , Feminino , Alemanha/epidemiologia , Humanos , Assistência de Longa Duração/legislação & jurisprudência , Assistência de Longa Duração/estatística & dados numéricos , Masculino
9.
Artigo em Alemão | MEDLINE | ID: mdl-23963234

RESUMO

A main factor for the development of shared-housing arrangements (SHA) was the wish of more self-determination in old age. Since January 2013 SHA is government-funded through the "Pflege-Neuausrichtungs-Gesetz" (PNG). Yet, an overview of the situation of SHA in Germany is not available. Therefore, a systematic literature search (databases CareLit, CINAHL, GeroLit, PubMed) was conducted in order to identify publications regarding resident- and care-specific characteristics, resident-related health outcomes and setting-specific quality management systems. The currently available knowledge in these fields is not exhaustive and further research is needed. The results indicate that care in SHA is not more efficient regarding residents' quality of life than in institutional care settings. Valid studies regarding the quality of care provision in SHA and conceptual basics concerning quality assessment are widely lacking. Thus, the goal of expanding SHA within the framework of the PNG has to be accompanied by in-depth health services research.


Assuntos
Moradias Assistidas/classificação , Moradias Assistidas/estatística & dados numéricos , Lares para Grupos/estatística & dados numéricos , Lares para Grupos/normas , Nível de Saúde , Garantia da Qualidade dos Cuidados de Saúde/estatística & dados numéricos , Qualidade de Vida , Alemanha/epidemiologia
10.
J Clin Pharm Ther ; 38(1): 77-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23016662

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Triptans are approved medications introduced for the acute treatment of migraine, classified as high-affinity serotonin 5-HT(1B/D) receptor agonists with lower affinity for 5-HT(1A) receptors. Both migraine and treatment of migraine with triptans have been associated with the development of major depression. However, little is known about the adverse effects of acute cessation of long-term overdose triptan use. CASE SUMMARY: We report a case of a 49-year-old male patient with first onset of severe major depression following cessation of daily excessive triptan use for 8 years. The depressive disorder was resistant to prior serotonergic antidepressant therapy. Antidepressant treatment with a non-serotonergic agent was successful in resolving depressive symptoms. WHAT IS NEW AND CONCLUSION: The present case report demonstrates for the first time that acute cessation of long-term excessive triptan use has the potential to induce severe major depression, presumably due to persistent alterations in the serotonergic system including downregulation and desensitization of 5-HT(1) receptors. In this case, treatment with a non-serotonergic agent could be a promising therapeutic strategy.


Assuntos
Transtorno Depressivo Maior/etiologia , Síndrome de Abstinência a Substâncias/complicações , Triptaminas/administração & dosagem , Transtorno Depressivo Maior/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/tratamento farmacológico , Índice de Gravidade de Doença , Fatores de Tempo
11.
Lett Appl Microbiol ; 52(5): 521-6, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21338378

RESUMO

AIMS: The aim of the work is to exploit the yeast pheromone system for controlled cell-cell communication and as an amplification circuit in technical applications, e.g. biosensors or sensor-actor systems. METHODS AND RESULTS: As a proof of principle, we developed recombinant Saccharomyces cerevisiae cells that express enhanced green fluorescent protein (EGFP) in response to different concentrations of the alpha(α)-factor mating pheromone. A respective reporter construct allowing the pheromone-driven expression of EGFP was transformed into the S. cerevisiae strains BY4741 and BY4741 bar1Δ. Upon addition of synthetic α-factor, the fluorescence strongly increases after 4 h. Furthermore, cells with constitutive α-factor expression were able to induce the expression of EGFP in co-cultivation with sensor cells only if both cell types were deleted for the gene BAR1, encoding α-factor protease. For technical applications, the immobilization of functionalized cells may be beneficial. We show that pheromone-induced expression of EGFP is effective in alginate-immobilized cells. CONCLUSIONS: Based on S. cerevisiae α-factor, we developed a controlled cell-cell communication system and amplification circuit for pheromone-driven expression of a target protein. The system is effective both in suspension and after cell immobilization. SIGNIFICANCE AND IMPACT OF THE STUDY: The developed set of recombinant yeast strains is the basis to apply the yeast pheromone system for signal production and amplification in biosensors or sensor-actor systems.


Assuntos
Técnicas Biossensoriais/métodos , Feromônios/metabolismo , Transdução de Sinais , Regulação Fúngica da Expressão Gênica , Proteínas de Fluorescência Verde/genética , Fator de Acasalamento , Peptídeos/farmacologia , Regiões Promotoras Genéticas/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/farmacologia , Transdução de Sinais/efeitos dos fármacos
12.
Nervenarzt ; 75(7): 663-74, 2004 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-15300322

RESUMO

This paper analyses sociodemographic, clinical, and descriptive data and data concerning cooperation in a sample of 305 consecutively treated inpatients with schizophrenia. The data of this group were compared with those from two other diagnostic groups (affective disorders, n=318; conduct disorders, n=982) who were treated as inpatients at the same time. Schizophrenic patients were significantly older at admittance (mean 17.6 years) than patients in the other two diagnostic groups (affective disorders 15.9 years, conduct disorders 13.1 years). On average, the inpatient treatment stay was longer in schizophrenic patients (by approximately 1 month) than in both of the other groups, and dropout was less frequent (5% vs 9% in affective disorders and 11% in conduct disorders). The treatment of the three patient groups was based on a multidimensional program following a model including five components: individual psychotherapy, family-centered measures, functional therapies, sociotherapeutic measures, and medication.


Assuntos
Admissão do Paciente/estatística & dados numéricos , Esquizofrenia/epidemiologia , Psicologia do Esquizofrênico , Adolescente , Fatores Etários , Transtorno da Personalidade Antissocial/diagnóstico , Transtorno da Personalidade Antissocial/epidemiologia , Transtorno da Personalidade Antissocial/reabilitação , Criança , Terapia Combinada , Estudos Transversais , Interpretação Estatística de Dados , Assistência Domiciliar/estatística & dados numéricos , Hospitais Psiquiátricos , Humanos , Tempo de Internação/estatística & dados numéricos , Transtornos do Humor/diagnóstico , Transtornos do Humor/epidemiologia , Transtornos do Humor/reabilitação , Alta do Paciente/estatística & dados numéricos , Garantia da Qualidade dos Cuidados de Saúde/estatística & dados numéricos , Centros de Reabilitação/estatística & dados numéricos , Esquizofrenia/diagnóstico , Esquizofrenia/reabilitação , Fatores Sexuais , Ajustamento Social , Resultado do Tratamento
13.
J Theor Biol ; 229(3): 327-38, 2004 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-15234200

RESUMO

In the present study, yeast colony development serves as a model system to study growth of fungal populations with negligible nutrient and signal transport within the mycelium. Mathematical simulations address the question whether colony development is governed by diffusional limitation of nutrients. A hybrid one-dimensional cellular automaton model was developed that describes growth of discrete cells based upon microscopic interaction rules in a continuous field of nutrient and messenger. The model is scaled for the geometry of the experimental setup, cell size, growth- and substrate uptake rates. Therefore, calculated cell density profiles and nutrient distributions can be compared to experimental results and the model assumptions can be verified. In the physiologically relevant parameter range, simulations show an exponentially declining cell density along the median axis of the colonies in case of a diffusion limited growth scenario. These results are in good agreement with cell density profiles obtained in cultivations of the yeast Candida boidinii with glucose as the limiting carbon source but stand in contrast to the constant cell density profile estimated for Yarrowia lipolytica grown under the same conditions. While from the comparison of experimental results and simulations a diffusion limited growth mechanism is proposed for glucose limited C. boidinii colonies, this hypothesis is rejected for the growth of Y. lipolytica. As an alternative, a quorum sensing model was developed that can explain the evolution of constant cell density profiles based on the effect of a not further characterized unstable or volatile messenger.


Assuntos
Modelos Biológicos , Leveduras/crescimento & desenvolvimento , Candida/crescimento & desenvolvimento , Divisão Celular/fisiologia , Yarrowia/crescimento & desenvolvimento
14.
Mol Reprod Dev ; 67(1): 15-8, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14648871

RESUMO

The gene germ cell-less (gcl) plays an important role in the early differentiation of germ cells in Drosophila. We isolated the gcl homolog of the model teleost medaka (Oryzias latipes) using degenerated primers and an ovary cDNA bank. The predicted amino acid sequence of medaka gcl showed 92, 68 and 31% overall identity to mouse, human and Drosophila gcl respectively. RT-PCR revealed stronger expression in the ovary and weaker expression in testis, brain, heart, liver and muscle tissue. Expression in early embryos indicates the presence of maternal mRNA. By in situ hybridisation (ISH), gcl could not be detected in embryos. In contrast to vasa, ISH revealed expression of gcl in the ovary but not in the testis. Mol. Reprod. Dev. 67: 15-18, 2004.


Assuntos
Proteínas de Drosophila/metabolismo , Células Germinativas/fisiologia , Proteínas Nucleares/metabolismo , Oryzias/fisiologia , Sequência de Aminoácidos , Animais , Diferenciação Celular/fisiologia , Proteínas de Drosophila/genética , Feminino , Células Germinativas/citologia , Humanos , Hibridização In Situ , Peptídeos e Proteínas de Sinalização Intercelular , Masculino , Dados de Sequência Molecular , Proteínas Nucleares/genética , Oryzias/anatomia & histologia , Oryzias/embriologia , Ovário/citologia , Ovário/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Testículo/citologia , Testículo/metabolismo , Distribuição Tecidual
16.
Yeast ; 16(4): 353-63, 2000 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10669873

RESUMO

Translation of cytochrome b mRNA in yeast mitochondria requires activation by the nuclear-encoded Cbs1p. According to the current model, Cbs1p tethers cytochrome b mRNA to the inner mitochondrial membrane via interaction with the 5'-untranslated leader. Cbs1p is predicted to be a hydrophilic protein with two hydrophobic segments near the carboxyl-terminal end, which are both too short to span the membrane. Nevertheless Cbs1p is tightly associated with the mitochondrial membrane, as shown by its behaviour in extraction experiments with taurodeoxycholate. In an attempt to define functionally important regions of Cbs1p, we created a number of mutant alleles by random and directed mutagenesis. We report that a Cbs1p mutant protein lacking the mitochondrial presequence is still able to complement a Deltacbs1 strain, suggesting that the presequence does not contain essential mitochondrial targeting information. Mutations in a cluster of positively charged amino acids at the extremeC-terminus have no effect on Cbs1p function, but removal of this segment severely impairs Cbs1p function. Truncation of 12 or more amino acids from the C-terminus results in a completely defective protein. We further show that both short hydrophobic regions are essential for Cbs1p function, although membrane association is observed even in the absence of these regions.


Assuntos
Grupo dos Citocromos b/genética , Proteínas Fúngicas/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Transativadores/metabolismo , Sequência de Aminoácidos , Western Blotting , Grupo dos Citocromos b/metabolismo , Análise Mutacional de DNA , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Biossíntese de Proteínas , RNA Fúngico/genética , RNA Fúngico/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Saccharomyces cerevisiae/metabolismo , Transativadores/genética , Transcrição Gênica
17.
FEBS Lett ; 447(1): 65-70, 1999 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-10218584

RESUMO

Cytochrome c oxidase is a multiprotein complex in the mitochondrial membrane whose biogenesis requires a number of proteins besides the structural subunits. Several yeast proteins as well as a human disease-related protein have been reported which are involved in cytochrome c oxidase assembly. The S. cerevisiae Sco1p protein has been implicated in the transfer of copper to cytochrome c oxidase subunits Cox1p and/or Cox2p. Here we report on the complementation behavior in yeast of two recently identified ScSco1p homologs of chromosome 17 and chromosome 22 from human. When allotropically expressed in yeast, both genes fail to complement the lack of the ScSCO1 gene. However, a chimera of the N-terminal half of ScSco1p and the C-terminal half of the chromosome 17 homolog does substitute for the ScSco1p function. Interestingly, the respective chimera with the human homolog of chromosome 22 is not able to complement. Expression of EGFP fusions in HeLa cells shows that both human ScSco1p homologs are located in the mitochondria of human cells.


Assuntos
Proteínas de Membrana/isolamento & purificação , Proteínas de Membrana/metabolismo , Mitocôndrias/química , Proteínas de Saccharomyces cerevisiae , Sequência de Aminoácidos , Compartimento Celular , Complexo IV da Cadeia de Transporte de Elétrons/biossíntese , Teste de Complementação Genética , Proteínas de Fluorescência Verde , Células HeLa , Humanos , Proteínas Luminescentes/genética , Proteínas Luminescentes/isolamento & purificação , Proteínas de Membrana/genética , Microscopia de Fluorescência , Proteínas Mitocondriais , Chaperonas Moleculares , Dados de Sequência Molecular , Consumo de Oxigênio , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/genética , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
18.
Curr Genet ; 35(2): 103-8, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10079328

RESUMO

Saccharomyces cerevisiae Sco1p is believed to be involved in the transfer of copper from the carrier Cox17p to the mitochondrial cytochrome c oxidase subunits 1 and 2. We here report on the results of a mutational analysis of Sco1p. The two cysteine residues of a potential metal-binding motif (CxxxC) are essential for protein function as shown by their substitution by alanines. Chimeras consisting of Sco1p and its homolog S. cerevisiae Sco2p restrict the specificity of Sco1p function to the N-terminal half of the protein. A candidate region for conferring specificity on Sco1p is a stretch of hydrophobic amino acids, which act as a membrane anchor. In line with this suggestion is the result that alterations of individual amino acids within this region impair Sco1p function.


Assuntos
Cobre/metabolismo , Mitocôndrias/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Sequência de Aminoácidos , Sítios de Ligação/genética , Complexo IV da Cadeia de Transporte de Elétrons/biossíntese , Proteínas Fúngicas/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação , Proteínas Recombinantes de Fusão/genética , Saccharomyces cerevisiae/genética , Deleção de Sequência , Homologia de Sequência de Aminoácidos
19.
Curr Genet ; 31(3): 248-54, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9065388

RESUMO

The Schizosaccharomyces pombe rhp51+, rad22+ and rhp54+ genes are homologous to RAD51, RAD52 and RAD54 respectively, which are indispensable in the recombinational repair of double-strand breaks (DSBs) in Saccharomyces cerevisiae. The rhp51Delta and rhp54Delta strains are extremely sensitive to ionizing radiation; the rad22Delta mutant turned out to be much less sensitive. Homologous recombination in these mutants was studied by targeted integration at the leu1-32 locus. These experiments revealed that rhp51Delta and rhp54Delta are equally impaired in the integration of plasmid molecules (15-fold reduction), while integration in the rad22Delta mutant is only reduced by a factor of two. Blot-analysis demonstrated that the majority of the leu+ transformants of the wild-type and rad22Delta strains have integrated one or more copies of the vector. Gene conversion events were observed in less than 10% of the transformants. Interestingly, the relative contribution of gene conversion events is much higher in a rhp51Delta and a rhp54Delta background. Meiotic recombination is hardly affected in the rad22Delta mutant. The rhp51Delta and rhp54Delta strains also show minor deficiencies in this type of recombination. The viability of spores is 46% in the rad22Delta strain and 27% in the rhp54Delta strain, as compared with wild-type cells. However, in the rhp51Delta mutant the spore viability is only 1.7%, suggesting an essential role for Rhp51 in meiosis. The function of Rhp51 and Rhp54 in damage repair and recombination resembles the role of Rad51 and Rad54 in S. cerevisiae. Compared with Rad52 from S. cerevisiae, Rad22 has a much less prominent role in the recombinational repair pathway in S. pombe.


Assuntos
DNA Helicases/fisiologia , Proteínas de Ligação a DNA , Proteínas Fúngicas/fisiologia , Recombinação Genética/genética , Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces/genética , DNA Helicases/genética , Reparo do DNA , Proteínas Fúngicas/genética , Conversão Gênica/genética , Meiose , Rad51 Recombinase , Saccharomyces cerevisiae/genética , Especificidade da Espécie , Esporos Fúngicos
20.
Mutat Res ; 315(3): 295-305, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7526206

RESUMO

The RAD52 gene of Saccharomyces cerevisiae is required for recombinational repair of double-strand breaks. Using degenerate oligonucleotides based on conserved amino acid sequences of RAD52 and rad22, its counterpart from Schizosaccharomyces pombe, RAD52 homologs from man and mouse were cloned by the polymerase chain reaction. DNA sequence analysis revealed an open reading frame of 418 amino acids for the human RAD52 homolog and of 420 amino acid residues for the mouse counterpart. The identity between the two proteins is 69% and the overall similarity 80%. The homology of the mammalian proteins with their counterparts from yeast is primarily concentrated in the N-terminal region. Low amounts of RAD52 RNA were observed in adult mouse tissues. A relatively high level of gene expression was observed in testis and thymus, suggesting that the mammalian RAD52 protein, like its homolog from yeast, plays a role in recombination. The mouse RAD52 gene is located near the tip of chromosome 6 in region G3. The human equivalent maps to region p13.3 of chromosome 12. Until now, this human chromosome has not been implicated in any of the rodent mutants with a defect in the repair of double-strand breaks.


Assuntos
Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Proteínas Fúngicas/genética , Recombinação Genética/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Mapeamento Cromossômico , Clonagem Molecular , Expressão Gênica , Genes Fúngicos/genética , Humanos , Camundongos , Dados de Sequência Molecular , Especificidade de Órgãos , RNA Mensageiro/análise , Proteína Rad52 de Recombinação e Reparo de DNA , Saccharomyces cerevisiae/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
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