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111.
A familial form of lupus, termed exfoliative cutaneous lupus erythematosus (ECLE) has been recognized for decades in German
shorthaired pointer dogs (GSP). Previous studies were suggestive of autosomal recessive inheritance. The disease presents
as a severe dermatitis with age of onset between 16 and 40 weeks, and mirrors cutaneous lupus erythematosus (CLE) in humans.
Lameness and, in advanced cases, renal disease may be present. Most affected dogs are euthanized before reaching the age of
4 years. The diagnosis is made by clinical observations and microscopic examination of skin biopsies. In humans, many different
forms of CLE exist and various genes and chromosomal locations have been implicated. The large number of potential candidate
loci combined with often weak association prevented in depth screening of the dog population thus far. During the course of
our studies, we developed a colony of dogs with ECLE as a model for human CLE and the genetic analysis of these dogs confirmed
the autosomal recessive mode of inheritance of CLE in GSPs. Using canine patient material, we performed a genome-wide association
study (GWAS) to identify the genomic region harboring the gene involved in the development of the disease in GSPs. We identified
a SNP allele on canine chromosome 18 that segregated with the disease in the 267 dogs tested. The data generated should allow
identification of the mutant gene responsible for this form of cutaneous lupus erythematosus in dogs and assist in the understanding
of the development of similar disease in humans. 相似文献
112.
GIGANTEA regulates phytochrome A-mediated photomorphogenesis independently of its role in the circadian clock 总被引:1,自引:0,他引:1 下载免费PDF全文
Oliverio KA Crepy M Martin-Tryon EL Milich R Harmer SL Putterill J Yanovsky MJ Casal JJ 《Plant physiology》2007,144(1):495-502
GIGANTEA (GI) is a nuclear protein involved in the promotion of flowering by long days, in light input to the circadian clock, and in seedling photomorphogenesis under continuous red light but not far-red light (FR). Here, we report that in Arabidopsis (Arabidopsis thaliana) different alleles of gi have defects in the hypocotyl-growth and cotyledon-unfolding responses to hourly pulses of FR, a treatment perceived by phytochrome A (phyA). This phenotype is rescued by overexpression of GI. The very-low-fluence response of seed germination was also reduced in gi. Since the circadian clock modulates many light responses, we investigated whether these gi phenotypes were due to alterations in the circadian system or light signaling per se. In experiments where FR pulses were given to dark-incubated seeds or seedlings at different times of the day, gi showed reduced seed germination, cotyledon unfolding, and activity of a luciferase reporter fused to the promoter of a chlorophyll a/b-binding protein gene; however, rhythmic sensitivity was normal in these plants. We conclude that while GI does not affect the high-irradiance responses of phyA, it does affect phyA-mediated very-low-fluence responses via mechanisms that do not obviously involve its circadian functions. 相似文献
113.
Alexandre ONeill Rita Araújo Margarida Casal Georg Guebitz Artur Cavaco-Paulo 《Enzyme and microbial technology》2007,40(7):1801-1805
The effect of agitation on adsorption, desorption and hydrolytic efficiency of a native and a genetically modified cutinase (L182A) on polyethylene terephthalate fibres is reported in this paper. The effect of mechanical agitation was studied using a shaker bath with orbital agitation and a Rotawash machine with vertical agitation with and without extra steel discs inside the reaction pots. The results obtained indicate that mechanical agitation combined with enzymatic action enhances the adsorption and activity of cutinases towards PET (polyethylene terephthalate) fibres. L182A showed higher adsorption than the native enzyme for all the levels of mechanical agitation. Lower units of L182A lead to similar yields of terephthalic acid formed in all levels of mechanical agitation. The highest increase of hydroxyl surface groups was found for the genetically modified L182A at the lowest level of mechanical agitation with a shaker bath. These results indicate that enzymatic functionalization of PET is favoured with a process with lower levels of mechanical agitation. 相似文献
114.
Teles-Grilo ML Tato-Costa J Duarte SM Maia A Casal G Azevedo C 《European journal of protistology》2007,43(2):163-167
Perkinsus atlanticus is a pathogenic protist that infects the clam Ruditapes decussatus. The recent proposal for the inclusion of the genus Perkinsus in a new phylum, Perkinsozoa, in the infra-kingdom Alveolata, gave rise to controversies whether this genus should form a phylum on its own. Molecular analysis of some conserved nuclear genes shows a closer proximity of the genus Perkinsus to the dinoflagellates than to the apicomplexans. Studies on extranuclear genomes, however, could also be very helpful for a more precise definition of those phyla. In Perkinsozoa, there have been until now no reports about the isolation of mitochondria as well as no conclusive results about the presence of any plastids, therefore a comparison with the data already obtained in Apicomplexa and Dinoflagellata has not yet been possible. In this work, we identify a plastid in Perkinsus atlanticus, using ultrastructural techniques and inhibition growth tests. It will be important to analyze the plastid genome at a molecular level, in order to confirm if the plastid in Perkinsus is more similar to those of Dinoflagellata or Apicomplexa. Such information will doubtless contribute to a more precise determination of the phylogenetic position of the genus Perkinsus. 相似文献
115.
Bruno Casal Rodríguez Berta Rivera Castiñeira Luis Currais Nunes 《Revista espa?ola de geriatría y gerontología》2019,54(2):81-87
Background
Along with an ageing population, a higher incidence of chronic diseases leads to increasingly complex health profiles. The relationship between survival, dependence, and social and demographic trends affecting caregiving, has led to an increase in the negative consequences associated with care provision. In this context, an assessment needs to be made on the impact that caregiving has on the well-being of the caregivers. The main aim of this article is to study the factors that determine the Quality of Life (QoL) of those who provide informal care to people suffering from Alzheimer's disease (AD).Methods
A total of 175 caregivers of people with AD were recruited through the Galician Association for Relatives with Alzheimer. These caregivers completed a questionnaire (EQ-5D) that gathered sociodemographic and health variables, QoL, and care characteristics. Multiple regression models were calculated to explain the QoL of the caregivers.Results
Of the five dimensions that the EQ-5D used to describe health, anxiety/depression was the one that concerned the largest percentage of caregivers who declared the highest levels of severity. The key variables for explaining QoL are those related to caregiver health status, periods of rest during caregiving, and the presence of a second caregiver.Conclusions
Maintaining a minimal QoL among the caregivers not only has repercussions on the caregivers themselves, but also has an impact on those receiving care and the entire health system, which would have to find replacements for those informal caregivers. 相似文献116.
Elena Granda Christine Scoffoni Alfredo E. Rubio‐Casal Lawren Sack Fernando Valladares 《Oikos》2014,123(11):1281-1290
Winter cold limits temperate plant performance, as does summer water stress in drought‐prone ecosystems. The relative impact of seasonal extremes on plant performance has received considerable attention for individual systems. An integrated study compiling the existing literature was needed to identify overall trends. First, we conducted a meta‐analysis of the impacts of summer and winter on ecophysiology for three woody plant functional types (winter deciduous angiosperms, evergreen angiosperms and conifers), including data for 210 records from 75 studies of ecosystems with and without summer drought across the temperate zone. Second, we tested predictions by conducting a case study in a drought‐prone Mediterranean ecosystem subject to winter freezing. As indicators of physiological response of leaves and xylem to seasonal stress, we focused on stomatal conductance (gs), percent loss of stem xylem hydraulic conductivity (PLC) and photochemical efficiency of photosystem II (Fv/Fm). Our meta‐analysis showed that in ecosystems without summer drought, gs was higher during summer than winter. By contrast, in drought‐prone ecosystems many species maintained open stomata during winter, with potential strong consequences for plant carbon gain over the year. Further, PLC tended to increase and Fv/Fm to decrease from summer to winter for most functional types and ecosystems due to low temperatures. Overall, deciduous angiosperms were most sensitive to climatic stress. Leaf gas exchange and stem xylem hydraulics showed a coordinated seasonal response at ecosystems without summer drought. In our Mediterranean site subjected to winter freezing the species showed similar responses to those typically found for ecosystems without summer drought. We conclude that winter stress is most extreme for systems without summer drought and systems with summer drought and winter freezing, and less extreme for drought‐prone systems without freezing. In all cases the evergreen species show less pronounced seasonal responses in both leaves and stems than deciduous species. 相似文献
117.
118.
Marina Perona Maria A. Dagrosa Romina Pagotto Mariana Casal Omar Pignataro Mario A. Pisarev Guillermo J. Juvenal 《Radiation and environmental biophysics》2014,53(3):611-619
We have previously reported the radioprotective effect of propylthiouracil (PTU) on thyroid cells. The aim of the present study was to analyze whether tumor cells and normal cells demonstrate the same response to PTU. Human colon carcinoma cells were irradiated with γ-irradiation with or without PTU. We evaluated the clonogenic survival, intracellular reactive oxygen species levels, catalase, superoxide dismutase and glutathione peroxidase activities, and apoptosis by nuclear cell morphology and caspase-3 activity assays. Cyclic AMP (cAMP) levels were measured by radioimmunoassay. PTU treatment increased surviving cell fraction at 2 Gy (SF2) from 56.9 ± 3.6 in controls to 75.0 ± 3.5 (p < 0.05) and diminished radiation-induced apoptosis. In addition, we observed that the level of antioxidant enzymes’ activity was increased in cells treated with PTU. Moreover, pretreatment with PTU increased intracellular levels of cAMP. Forskolin (p < 0.01) and dibutyryl cAMP (p < 0.05) mimicked the effect of PTU on SF2. Co-treatment with H89, an inhibitor of protein kinase A, abolished the radioprotective effect of PTU. PTU reduces the toxicity of ionizing radiation by increasing cAMP levels and also possibly through a reduction in apoptosis levels and in radiation-induced oxidative stress damage. We therefore conclude that PTU protects both normal and cancer cells during exposure to radiation in conditions mimicking the radiotherapy. 相似文献
119.
120.