Search results for "REGIONS"
showing 10 items of 1521 documents
Forced Retroevolution of an RNA Bacteriophage
2000
AbstractThe operator hairpin ahead of the replicase gene in RNA bacteriophage MS2 contains overlapping signals for binding the coat protein and ribosomes. Coat protein binding inhibits further translation of the gene and forms the first step in capsid formation. The hairpin sequence was partially randomized to assess the importance of this structure element for the bacteriophage and to monitor alternative solutions that would evolve on the passaging of mutant phages. The evolutionary reconstruction of the operator failed in the majority of mutants. Instead, a poor imitation developed containing only some of the recognition signals for the coat protein. Three mutants were of particular inter…
261 INFLUENCE OF IN VITRO MATURATION ON EPIGENETIC MARKS AND GENE EXPRESSION IN BOVINE OOCYTES
2011
In cattle, in vitro maturation (IVM) of oocytes is an integral part of assisted reproduction technology. However, only 30% of in vitro matured bovine oocytes develop to the blastocyst stage after fertilization (compared with 60% for in vivo matured oocytes), indicating critical involvement of maturation conditions in the developmental competence of oocytes. Oocytes for IVF and intracytoplasmic sperm injection in humans are typically allowed to mature in vivo after superovulation because IVM is not considered to be a safe medical procedure. Several studies have shown that assisted reproduction technology involving prolonged in vitro culture of human and ruminant embryos can be associated wi…
Transcriptional and Structural Study of a Region of Two Convergent Overlapping Yeast Genes
1999
The exceptionally close packing of many yeast genes and other chromosomal elements raises the question of how those elements are functionally insulated. All published work shows that natural insulators are very effective, but transcriptional interference (TI) occurs if they are mutated or if their natural context is altered. Mechanisms to avoid TI are poorly understood, but are thought to involve an interplay of cis sequences and trans factors in a chromatin context. We have studied the case of two convergent closely packed ORFs (56 bp of separation) in chromosome IX of Saccharomyces cerevisiae. mRNAs from POT1 and YIL161w overlap by up to 115 nt. Convergent transcription causes a small but…
Genetic manipulation of HSP26 and YHR087W stress genes may improve fermentative behaviour in wine yeasts under vinification conditions
2008
Throughout wine production yeast cells are affected by a plethora of stress conditions that compromise their ability to carry out the whole process. In recent years important knowledge about the mechanisms involved in stress response in both laboratory and wine yeast strains has been obtained. Several studies have indicated that a correlation exists between stress resistance, expression of stress response genes and fermentative behaviour. In this work we introduce several genetic manipulations in two genes induced by several stress conditions: HSP26 (which encodes a heat shock protein) and YHR087W (encoding a protein of unknown function) in two different wine yeasts, ICV16 and ICV27. These …
Genetic Variability of Hepatitis C Virus before and after Combined Therapy of Interferon plus Ribavirin
2008
We present an analysis of the selective forces acting on two hepatitis C virus genome regions previously postulated to be involved in the viral response to combined antiviral therapy. One includes the three hypervariable regions in the envelope E2 glycoprotein, and the other encompasses the PKR binding domain and the V3 domain in the NS5A region. We used a cohort of 22 non-responder patients to combined therapy (interferon alpha-2a plus ribavirin) for which samples were obtained before initiation of therapy and after 6 or/and 12 months of treatment. A range of 25-100 clones per patient, genome region and time sample were sequenced. These were used to detect general patterns of adaptation, t…
Chromatin structure of the yeast SUC2 promoter in regulatory mutants
1992
We have previously suggested that two positioned nucleosomes are removed from the promoter of the Saccharomyces cerevisiae SUC2 gene upon derepression by glucose starvation. To gain further insight into the changes accompanying derepression at the chromatin level we have studied the chromatin structure of the SUC2 promoter in several mutants affecting SUC2 expression. The non-derepressible mutants snf1, snf2 and snf5 present a chromatin structure characteristic of the repressed state, irrespective of the presence or absence of glucose. The non-repressible mutants, mig1 and ssn6, as well as the double mutant snfs sn6 exhibit an opened chromatin structure even in the presence of glucose. Thes…
Characteristics and definition and characterization of new Valencian urban areas
2014
La expansión urbanística, junto con la generalización de los procesos de descentralización residencial y económica, ha conducido a un nuevo modelo de ciudad dispersa caracterizado por la dificultad de establecer sus límites precisos. Utilizando un índice de densidad de ejes viarios procedente de una fuente comercial, y por tanto fácilmente actualizable, se ha delimitado el fenómeno urbano en la Comunidad Valenciana. Se discute la utilidad de la metodología y su capacidad para captar el hecho urbano a partir del contraste con la cartografía de usos del suelo de Corine. Urban expansion, along with the generalization of the processes of residential and economic decentralization has led to a ne…
Calidad de vida en Argentina: percepciones macro y micro-sociales
2012
El artículo presenta los resultados de un estudio desarrollado en Argentina que diferencia laopinión de ciudadanos acerca de su calidad de vida, para dicho estudio se tomaron en cuentados zonas geográficas específicas, la Ciudad Autónoma de Buenos Aires y los Partidos delGran Buenos Aires. Se midió el nivel de satisfacción con la calidad de vida en el país y con lacalidad de vida personal a partir de la utilización de diferentes instrumentos: escala de satisfacción con la calidad de vida en el país (ESCVP), escala de satisfacción con la vida (SWLS)y encuesta de áreas vitales.
Consequences of Sarcopenia in Older People: The Epidemiological Evidence
2021
Sarcopenia is a common condition in older people. Increasing literature is showing its importance for negative health outcomes, also beyond the perimeter of geriatric medicine. In this chapter, we will discuss the consequences of sarcopenia. Overall, epidemiological research suggests that sarcopenia is significantly associated with falls and fractures also suggesting a strong association between muscle and bone loss conditions, as in the case of osteosarcopenia. Moreover, sarcopenia is associated with disability, hospitalization (particularly in older people already hospitalized), and finally mortality. Increasing research is also showing that sarcopenia is associated with negative outcomes…
Sarcopenic osteoarthritis: a new entity in geriatric medicine?
2018
Purpose: Osteoarthritis, a disease characterized by cartilage degradation, abnormal subchondral bone remodeling and some grade of inflammation, and sarcopenia, a condition of low muscle mass associated with reduced strength and function, are prevalent disorders in older adults. In this review, we examine what is known about the relationship between osteoarthritis and sarcopenia, with particular focus on the older population. We also discuss how osteoarthritis and sarcopenia may interact and affect each other in clinical progression and the potential benefits from developing treatments that address such muscular-skeletal interaction. Methods: We searched in Pubmed and Scopus through a combin…