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71.
Gloria Paniagua-Contreras Eric Monroy-Pérez Raúl Gutiérrez-Lucas Teresita Sainz-Espuñes Jaime Bustos-Martínez Sergio Vaca 《Folia microbiologica》2014,59(4):295-302
Methicillin-resistant Staphylococcus aureus (MRSA) is the causal agent of multiple nosocomial infections worldwide, including catheter-associated bacteremia in hemodialysis patients. The purposes of this work were to genetically characterize a group of MRSA isolates from catheter-related infections of ambulatory Mexican hemodialysis patients and to determine whether the strains are the same as those carried by the patients in their anterior nares. Sixteen pairs of MRSA isolates from the catheter (cat) and anterior nares (N) of hemodialysis patients were compared using pulsed-field gel electrophoresis (PFGE), PCR detection of adhesion genes and other virulence markers, and an antibiogram. Three pairs of N/cat MRSA isolates (18.7 %) with identical resistograms also showed the same combination of PCR-detected markers and PFGE pattern; one additional pair showed only an identical electrophoretic PFGE pattern. Of the MRSA isolates, 75 % (n?=?24) were resistant to ≥7 antibiotics, 4 isolates were resistant to 11 antibiotics, and 7 isolates were resistant to the 12 antibiotics tested. The most frequent virulence marker combination found was spa, clfA, clfB, cna, bbp, ebps, map/eap, sdrC, sdrD, sdrE, ica, agr (65.6 %, n?=?21). The SCCmec alleles of the 32 MRSA isolates were IV (n?=?20), I (n?=?7), II (n?=?4), and V (n?=?1), and no SCCmec type III MRSA was found. The genotypic characterization of the MRSA isolates studied in this work will contribute to a better understanding of the virulence gene makeup of catheter-colonizing S. aureus strains and will help to lower the infection risk in these patients. 相似文献
72.
Álvaro García-Soler Cristina Buiza Bueno Raúl Vaca Bermejo Xabier Ansorena Urchegui 《Revista espa?ola de geriatría y gerontología》2014
Introduction
As the level of cognitive impairment in people with dementia increases, it seems that the interventions aimed at this group do not obtain the expected results. Thus, it is clear that there is a need to develop specific assessment tools. One of the important aspects in people with dementia is the engagement, involvement in task and activities. Engagement is considered a quality of life and quality of care indicator. The aim of the study is to develop an Engagement recording tool for mapping people with dementia, and to obtain reliability measures.Method
The present paper aims to present the current development of engagement behaviours. The pilot study had a sample of 19 people distributed into two groups, which were observed in order to obtain inter-rater reliability measurements using the percentage of inter-rater agreement.Results
An observational mapping instrument was developed that achieved a high inter-rater reliability.Conclusion
The Engagement recording tool makes it possible to gather promising results on the effects of the interventions for people with severe dementia. On the other hand, these results point to the possibilities of more specific tools to assess the different interventions which aim is to improve quality of life and quality of care in people with dementia. 相似文献73.
Philip J Cooper Martha E Chico Maritza G Vaca Alejandro Rodriguez Neuza M Alcântara-Neves Bernd Genser Lain Pontes de Carvalho Renato T Stein Alvaro A Cruz Laura C Rodrigues Mauricio L Barreto 《BMC pulmonary medicine》2006,6(1):1-9
Background
This study examined the attitudes and actions of 3415 physician-recruited adults aged ≥ 16 years with asthma in eleven countries who were prescribed regular maintenance therapy with inhaled corticosteroids or inhaled corticosteroids plus long-acting β2-agonists.Methods
Structured interviews were conducted to assess medication use, asthma control, and patients' ability to recognise and self-manage worsening asthma.Results
Despite being prescribed regular maintenance therapy, 74% of patients used short-acting β2-agonists daily and 51% were classified by the Asthma Control Questionnaire as having uncontrolled asthma. Even patients with well-controlled asthma reported an average of 6 worsenings/year. The mean period from the onset to the peak symptoms of a worsening was 5.1 days. Although most patients recognised the early signs of worsenings, the most common response was to increase short-acting β2-agonist use; inhaled corticosteroids were increased to a lesser extent at the peak of a worsening.Conclusion
Previous studies of this nature have also reported considerable patient morbidity, but in those studies approximately three-quarters of patients were not receiving regular maintenance therapy and not all had a physician-confirmed diagnosis of asthma. This study shows that patients with asthma receiving regular maintenance therapy still have high levels of inadequately controlled asthma. The study also shows that patients recognise deteriorating asthma control and adjust their medication during episodes of worsening. However, they often adjust treatment in an inappropriate manner, which represents a window of missed opportunity. 相似文献74.
75.
Ma?lle Connan Christopher M. R. Kelly Christopher D. McQuaid Bo T. Bonnevie Nigel P. Barker 《Polar Biology》2011,34(6):791-798
The two fuliginous albatross species, Phoebetria fusca (the Sooty albatross, SA) and P. palpebrata (the Light-mantled albatross, LMA), are found breeding close to each other on the Prince Edward Islands (Southern Ocean).
Adults of these two species are easy to identify in the field, but the chicks are difficult to distinguish on the basis of
external morphology, especially at very young ages. Many ecological studies involve sampling of chicks as well as adults,
and accurate field identification of chicks is thus crucial. Traditionally, the extent of the ring of pale feathers around
the eye (eye-ring) has been used to identify the fledglings. The aim of our study was to investigate the utility of characters
associated with the eye-ring (extent, measured as an angle, and colour) for the identification of Phoebetria chicks. This was achieved by comparison of identifications based on morphology, with positive identifications based on DNA
sequence data from the mitochondrial cytochrome b gene. We confirm the value of morphological criteria in distinguishing LMA and SA chicks, and this technique appears to be
accurate in the majority of cases (>80%). However, we recommend using molecular identification for borderline cases (angle
of the eye-ring measuring between 85 and 95°) if independent confirmation of chick identity cannot be obtained (e.g. via observed
feeding interaction with an adult). 相似文献
76.
There has been significant recent interest in the commercial utilisation of algae based on their valuable chemical constituents many of which exhibit multiple bioactivities with applications in the food, cosmetic, agri- and horticultural sectors and in human health. Compounds of particular commercial interest include pigments, lipids and fatty acids, proteins, polysaccharides and phenolics which all display considerable diversity between and within taxa. The chemical composition of natural algal populations is further influenced by spatial and temporal changes in environmental parameters including light, temperature, nutrients and salinity, as well as biotic interactions. As reported bioactivities are closely linked to specific compounds it is important to understand, and be able to quantify, existing chemical diversity and variability. This review outlines the taxonomic, ecological and chemical diversity between, and within, different algal groups and the implications for commercial utilisation of algae from natural populations. The biochemical diversity and complexity of commercially important types of compounds and their environmental and developmental control are addressed. Such knowledge is likely to help achieve higher and more consistent levels of bioactivity in natural samples and may allow selective harvesting according to algal species and local environmental conditions for different groups of compounds. 相似文献
77.
Gavin M. Rishworth Yann Tremblay David B. Green Ma?lle Connan Pierre A. Pistorius 《PloS one》2014,9(12)
During breeding, animal behaviour is particularly sensitive to environmental and food resource availability. Additionally, factors such as sex, body condition, and offspring developmental stage can influence behaviour. Amongst seabirds, behaviour is generally predictably affected by local foraging conditions and has therefore been suggested as a potentially useful proxy to indicate prey state. However, besides prey availability and distribution, a range of other variables also influence seabird behavior, and these need to be accounted for to increase the signal-to-noise ratio when assessing specific characteristics of the environment based on behavioural attributes. The aim of this study was to use continuous, fine-scale time-activity budget data from a pelagic seabird (Cape gannet, Morus capensis) to determine the influence of intrinsic (sex and body condition) and extrinsic (offspring and time) variables on parent behaviour during breeding. Foraging trip duration and chick provisioning rates were clearly sex-specific and associated with chick developmental stage. Females made fewer, longer foraging trips and spent less time at the nest during chick provisioning. These sex-specific differences became increasingly apparent with chick development. Additionally, parents in better body condition spent longer periods at their nests and those which returned later in the day had longer overall nest attendance bouts. Using recent technological advances, this study provides new insights into the foraging behaviour of breeding seabirds, particularly during the post-guarding phase. The biparental strategy of chick provisioning revealed in this study appears to be an example where the costs of egg development to the female are balanced by paternal-dominated chick provisioning particularly as the chick nears fledging. 相似文献
78.
Meneses-Ruiz DM Laclette JP Aguilar-Díaz H Hernández-Ruiz J Luz-Madrigal A Sampieri A Vaca L Carrero JC 《International journal of biological sciences》2011,7(9):1345-1356
Mucosal vaccination against amoebiasis using the Gal-lectin of E. histolytica has been proposed as one of the leading strategies for controlling this human disease. However, most mucosal adjuvants used are toxic and the identification of safe delivery systems is necessary. Here, we evaluate the potential of a recombinant Autographa californica baculovirus driving the expression of the LC3 fragment of the Gal-lectin to confer protection against amoebic liver abscess (ALA) in hamsters following oral or nasal immunization. Hamsters immunized by oral route showed complete absence (57.9%) or partial development (21%) of ALA, resulting in some protection in 78.9% of animals when compared with the wild type baculovirus and sham control groups. In contrast, nasal immunization conferred only 21% of protection efficacy. Levels of ALA protection showed lineal correlation with the development of an anti-amoebic cellular immune response evaluated in spleens, but not with the induction of seric IgG anti-amoeba antibodies. These results suggest that baculovirus driving the expression of E. histolytica vaccine candidate antigens is useful for inducing protective cellular and humoral immune responses following oral immunization, and therefore it could be used as a system for mucosal delivery of an anti-amoebic vaccine. 相似文献
79.
Panizza de León A Carrillo González R Bernal González M Vaca Mier M Durán-Domínguez-de-Bazúa C 《International journal of phytoremediation》2011,13(5):421-433
In this study, the capacity of an ornamental species (Coleus blumei) to extract and accumulate aluminum was evaluated. The analyzed parameters were amount of soluble aluminum, radical growth, tolerance rate, bioaccumulation factor, and tissues aluminum concentration. The main limiting factor for aluminum accumulation is the availability of the metal. However, Coleus blumei can grow and accumulate up to 1445.7 mg kg(-1) of aluminum dry base. This plant can play an important role in the treatment of polluted water with metals, since it can grow in conditions with a pH of around 4.8. The aluminum tolerance rate showed for this plant ranged between 18.8% and 25%. Therefore, this species behaves as a non-accumulator, even though the bioaccumulation factor was 3098.5 L kg(-1). 相似文献
80.
There is a specialized form of calcium influx that involves a close communication between endoplasmic reticulum and the channels at the plasma membrane. In one side store depletion activates channels known as store-operated channels (SOC), which are responsible of the well-studied store-operated calcium entry (SOCE). SOC comprises two different types of channels. Orai, which is exclusively activated by store depletion being the channel responsible of the calcium release-activated calcium current, and transient receptor potential canonical channel, which in contrast, is activated by store depletion only under specific conditions and carries nonselective cationic currents. On the other hand, it has been recently shown that store depletion also inhibits calcium channels. The first member identified, of what we named as store-inhibited channels (SIC), is the L-type voltage-gated calcium channel. Stores control both SOC and SIC by means of the multifunctional protein STIM1. The identification of SOC and SIC opens a new scenario for the role of store depletion in the modulation of different calcium entry pathways, which may satisfy different cellular processes. 相似文献