João Simões

Reversion of a fungal genetic code alteration links proteome instability with genomic and phenotypic diversification

Many fungi restructured their proteomes through incorporation of serine (Ser) at thousands of protein sites coded by the leucine (Leu) CUG codon. How these fungi survived this potentially lethal genetic code alteration and its relevance for their biology are not understood. Interestingly, the human pathogen Candida albicans maintains variable Ser and Leu incorporation levels at CUG sites, suggesting that this atypical codon assignment flexibility provided an effective mechanism to alter the genetic code. To test this hypothesis, we have engineered C. albicans strains to misincorporate increasing levels of Leu at protein CUG sites. Tolerance to the misincorporations was very high, and one strain accommodated the complete reversion of CUG identity from Ser back to Leu. Increasing levels of Leu misincorporation decreased growth rate, but production of phenotypic diversity on a phenotypic array probing various metabolic networks, drug resistance, and host immune cell responses was impressive. Genome resequencing revealed an increasing number of genotype changes at polymorphic sites compared with the control strain, and 80% of Leu misincorporation resulted in complete loss of heterozygosity in a large region of chromosome V. The data unveil unanticipated links between gene translational fidelity, proteome instability and variability, genome diversification, and adaptive phenotypic diversity. They also explain the high heterozygosity of the C. albicans genome and open the door to produce microorganisms with genetic code alterations for basic and applied research.

Ethanol Exposure Induces Upregulation of Specific MicroRNAs in Zebrafish Embryos

Prenatal exposure to ethanol leads to a myriad of developmental disorders known as fetal alcohol spectrum disorder, often characterized by growth and mental retardation, central nervous system damage, and specific craniofacial dysmorphic features. The mechanisms of ethanol toxicity are not fully understood, but exposure during development affects the expression of several genes involved in cell cycle control, apoptosis, and transcriptional regulation. MicroRNAs (miRNAs) are implicated in some of these processes, however, it is not yet clear if they are involved in ethanol-induced toxicity. In order to clarify this question, we have exposed zebrafish embryos to ethanol and evaluated whether a miRNA deregulation signature could be obtained. Zebrafish embryos were exposed to 1 and 1.5% of ethanol from 4 h postfertilization (hpf) to 24 hpf. The miRNA expression profiles obtained reveal significant miRNA deregulation and show that both ethanol concentrations upregulate miR-153a, miR-725, miR-30d, let-7k, miR-100, miR-738, and miR-732. Putative gene targets of deregulated miRNAs are involved in cell cycle control, apoptosis, and transcription, which are the main processes affected by ethanol toxicity. The conservation of affected mechanisms among vertebrates leads us to postulate that similar miRNA deregulation occurs in humans, highlighting a relevant role of miRNAs in ethanol toxicology.

Low level genome mistranslations deregulate the transcriptome and translatome and generate proteotoxic stress in yeast

BackgroundOrganisms use highly accurate molecular processes to transcribe their genes and a variety of mRNA quality control and ribosome proofreading mechanisms to maintain intact the fidelity of genetic information flow. Despite this, low level gene translational errors induced by mutations and environmental factors cause neurodegeneration and premature death in mice and mitochondrial disorders in humans. Paradoxically, such errors can generate advantageous phenotypic diversity in fungi and bacteria through poorly understood molecular processes.ResultsIn order to clarify the biological relevance of gene translational errors we have engineered codon misreading in yeast and used profiling of total and polysome-associated mRNAs, molecular and biochemical tools to characterize the recombinant cells. We demonstrate here that gene translational errors, which have negligible impact on yeast growth rate down-regulate protein synthesis, activate the unfolded protein response and environmental stress response pathways, and down-regulate chaperones linked to ribosomes.ConclusionsWe provide the first global view of transcriptional and post-transcriptional responses to global gene translational errors and we postulate that they cause gradual cell degeneration through synergistic effects of overloading protein quality control systems and deregulation of protein synthesis, but generate adaptive phenotypes in unicellular organisms through activation of stress cross-protection. We conclude that these genome wide gene translational infidelities can be degenerative or adaptive depending on cellular context and physiological condition.

Assessment of comatose patients: a Portuguese instrument based on the Coma Recovery Scale – Revised and using nursing standard terminology

AIMS To translate and adapt the Coma Recovery Scale - Revised to Portuguese using the ICNP® (International Classification of Nursing Practice) terminology and to determine if it can be administered reliably across examiners. BACKGROUND Assessment tools for the person in a coma can contribute to the planning, implementation and evaluation of care. It also strengthens the autonomy and responsibility of nurses, contributing to the safety, quality and satisfaction of those who deliver and receive care. This allows the sharing of information amongst healthcare professionals and supports decision-making within a multidisciplinary team. METHODS A convenience sample of 20 patients admitted to an intensive care unit constituted the study participants. The data were collected during 2009. The instrument was administered by the same two raters in all the patients on two consecutive days. The total and subscale score agreement was then examined, using inter-rater and test-retest analyses. The intercorrelation dependencies between the subscales were also analysed. RESULTS The results of the analyses suggest that the instrument can be used reliably, even when there are some patient fluctuations. The correlation of the subscale scores was high and better than the results presented for the original Coma Recovery Scale - Revised, indicating that this scale is a homogeneous measure of neurobehavioural function. CONCLUSION The new instrument can be administered reliably by trained examiners and produces a high degree of reproducibility in scores between raters over repeated assessments. We believe that assessment tools that can assess the communication ability of patients will be relevant to evaluating the continuity of care, and promote the effectiveness of care.

Finalidade das estratégias de supervisão utilizadas em ensino clínico de enfermagem

O presente artigo resulta de trabalhos de grupo realizados por enfermeiros durante uma formacao sobre o processo de supervisao, leccionada pelos autores enquanto membros do Centro de Estagios da Escola Superior de Saude da Universidade de Aveiro - Portugal. Tem como objectivos aprofundar conhecimentos acerca desta tematica, identificar a finalidade das estrategias que sao utilizadas e a quais dao mais enfase. A recolha de dados foi realizada atraves da narracao de episodios significativos, por 20 enfermeiros cooperantes na supervisao, no periodo de janeiro a fevereiro de 2005. Desenvolveu-se um estudo exploratorio-qualitativo tendo-se procedido a analise de conteudo das referidas narracoes. Com o presente estudo verificamos que os enfermeiros, utilizam as estrategias de supervisao com a finalidade de prestar atencao, clarificar, encorajar, servir de espelho, dar opiniao, ajudar a encontrar solucoes para os problemas, negociar, orientar, estabelecer criterios e condicionar. Da analise dos resultados concluimos que os supervisores deste estudo se aproximam de um perfil nao-directivo.El presente articulo resulta de trabajos de grupo realizados por enfermeros durante una formacion sobre el proceso de supervision, el cual fue ensenado por los autores como miembros del Centro de Practica Clinica de la Escuela Superior de Salud de la Universidad de Aveiro - Portugal. Su objetivo es profundizar el conocimiento referente a esta tematica, para identificar el proposito de las estrategias que se utilizan y saber a cuales dan mas enfasis. La recoleccion de los datos fue realizada por 20 enfermeros cooperativos en la supervision, a traves de la narracion de episodios significativos, en el periodo de enero a febrero de 2005. Se desarrollo un estudio exploratorio de naturaleza cualitativa, analizado el contenido de las referidas narraciones. Con el presente estudio pudimos concluir que los enfermeros utilizan las estrategias de supervision con el proposito de dar atencion, aclarar, animar, servir de espejo, dar la opinion, ayudar a encontrar las soluciones para los problemas, a negociar, a orientar, a establecer criterios y a condicionar. Del analisis de los resultados concluimos que los supervisores de este estudio se acercan a un perfil no directivo.

The Fungus Candida albicans Tolerates Ambiguity at Multiple Codons

The ascomycete Candida albicans is a normal resident of the gastrointestinal tract of humans and other warm-blooded animals. It occurs in a broad range of body sites and has high capacity to survive and proliferate in adverse environments with drastic changes in oxygen, carbon dioxide, pH, osmolarity, nutrients, and temperature. Its biology is unique due to flexible reassignment of the leucine CUG codon to serine and synthesis of statistical proteins. Under standard growth conditions, CUG sites incorporate leucine (3% of the times) and serine (97% of the times) on a proteome wide scale, but leucine incorporation fluctuates in response to environmental stressors and can be artificially increased up to 98%. In order to determine whether such flexibility also exists at other codons, we have constructed several serine tRNAs that decode various non-cognate codons. Expression of these tRNAs had minor effects on fitness, but growth of the mistranslating strains at different temperatures, in medium with different pH and nutrients composition was often enhanced relatively to the wild type (WT) strain, supporting our previous data on adaptive roles of CUG ambiguity in variable growth conditions. Parallel evolution of the recombinant strains (100 generations) followed by full genome resequencing identified various strain specific single nucleotide polymorphisms (SNP) and one SNP in the deneddylase (JAB1) gene in all strains. Since JAB1 is a subunit of the COP9 signalosome complex, which interacts with cullin (Cdc53p) to mediate degradation of a variety of cellular proteins, our data suggest that neddylation plays a key role in tolerance and adaptation to codon ambiguity in C. albicans.

Purpose of supervision strategies used in nursing clinical practice

O presente artigo resulta de trabalhos de grupo realizados por enfermeiros durante uma formacao sobre o processo de supervisao, leccionada pelos autores enquanto membros do Centro de Estagios da Escola Superior de Saude da Universidade de Aveiro - Portugal. Tem como objectivos aprofundar conhecimentos acerca desta tematica, identificar a finalidade das estrategias que sao utilizadas e a quais dao mais enfase. A recolha de dados foi realizada atraves da narracao de episodios significativos, por 20 enfermeiros cooperantes na supervisao, no periodo de janeiro a fevereiro de 2005. Desenvolveu-se um estudo exploratorio-qualitativo tendo-se procedido a analise de conteudo das referidas narracoes. Com o presente estudo verificamos que os enfermeiros, utilizam as estrategias de supervisao com a finalidade de prestar atencao, clarificar, encorajar, servir de espelho, dar opiniao, ajudar a encontrar solucoes para os problemas, negociar, orientar, estabelecer criterios e condicionar. Da analise dos resultados concluimos que os supervisores deste estudo se aproximam de um perfil nao-directivo.El presente articulo resulta de trabajos de grupo realizados por enfermeros durante una formacion sobre el proceso de supervision, el cual fue ensenado por los autores como miembros del Centro de Practica Clinica de la Escuela Superior de Salud de la Universidad de Aveiro - Portugal. Su objetivo es profundizar el conocimiento referente a esta tematica, para identificar el proposito de las estrategias que se utilizan y saber a cuales dan mas enfasis. La recoleccion de los datos fue realizada por 20 enfermeros cooperativos en la supervision, a traves de la narracion de episodios significativos, en el periodo de enero a febrero de 2005. Se desarrollo un estudio exploratorio de naturaleza cualitativa, analizado el contenido de las referidas narraciones. Con el presente estudio pudimos concluir que los enfermeros utilizan las estrategias de supervision con el proposito de dar atencion, aclarar, animar, servir de espejo, dar la opinion, ayudar a encontrar las soluciones para los problemas, a negociar, a orientar, a establecer criterios y a condicionar. Del analisis de los resultados concluimos que los supervisores de este estudio se acercan a un perfil no directivo.

The Influence of Presurgical Factors on the Rehabilitation Outcome of Patients Following Hip Arthroplasty

PURPOSE The aims of this study were to evaluate the relationship between sociodemographic information, anthropometric values, clinical and presurgery factors, and length of stay (LOS) in older adult patients undergoing total hip arthroplasty (THA) and to predict which factors can delay the start of the rehabilitation program and increase the corresponding LOS. METHODS A prospective cohort study was conducted in an orthopedic inpatient unit with 40 patients undergoing THA. FINDINGS The Morse Fall Scale scores and pain intensity scores delayed the commencement of the rehabilitation program. Gender and social support were important determinants of LOS and rehabilitation outcome following THA. The weight of the lower limb without osteoarthritis followed by pain intensity and overweight patients also influenced LOS. CONCLUSIONS/CLINICAL RELEVANCE Functional outcomes after THA are variable, and the rehabilitation process is an important factor to regain their normal level of physical functioning. This factor can have an impact in the discharge of patients, in resource allocation and in health care of older adult patients.

El propósito de las estrategias de supervisión usadas en la prática clínica del oficio de enfermería

O presente artigo resulta de trabalhos de grupo realizados por enfermeiros durante uma formacao sobre o processo de supervisao, leccionada pelos autores enquanto membros do Centro de Estagios da Escola Superior de Saude da Universidade de Aveiro - Portugal. Tem como objectivos aprofundar conhecimentos acerca desta tematica, identificar a finalidade das estrategias que sao utilizadas e a quais dao mais enfase. A recolha de dados foi realizada atraves da narracao de episodios significativos, por 20 enfermeiros cooperantes na supervisao, no periodo de janeiro a fevereiro de 2005. Desenvolveu-se um estudo exploratorio-qualitativo tendo-se procedido a analise de conteudo das referidas narracoes. Com o presente estudo verificamos que os enfermeiros, utilizam as estrategias de supervisao com a finalidade de prestar atencao, clarificar, encorajar, servir de espelho, dar opiniao, ajudar a encontrar solucoes para os problemas, negociar, orientar, estabelecer criterios e condicionar. Da analise dos resultados concluimos que os supervisores deste estudo se aproximam de um perfil nao-directivo.El presente articulo resulta de trabajos de grupo realizados por enfermeros durante una formacion sobre el proceso de supervision, el cual fue ensenado por los autores como miembros del Centro de Practica Clinica de la Escuela Superior de Salud de la Universidad de Aveiro - Portugal. Su objetivo es profundizar el conocimiento referente a esta tematica, para identificar el proposito de las estrategias que se utilizan y saber a cuales dan mas enfasis. La recoleccion de los datos fue realizada por 20 enfermeros cooperativos en la supervision, a traves de la narracion de episodios significativos, en el periodo de enero a febrero de 2005. Se desarrollo un estudio exploratorio de naturaleza cualitativa, analizado el contenido de las referidas narraciones. Con el presente estudio pudimos concluir que los enfermeros utilizan las estrategias de supervision con el proposito de dar atencion, aclarar, animar, servir de espejo, dar la opinion, ayudar a encontrar las soluciones para los problemas, a negociar, a orientar, a establecer criterios y a condicionar. Del analisis de los resultados concluimos que los supervisores de este estudio se acercan a un perfil no directivo.