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31.
R. Gómez-Huelgas F. Gómez Peralta L. Rodríguez Mañas F. Formiga M. Puig Domingo J.J. Mediavilla Bravo C. Miranda J. Ena 《Revista espa?ola de geriatría y gerontología》2018,53(2):89-99
The prevalence of type 2 diabetes mellitus (DM2) increases markedly with age. Antidiabetic treatment and the objectives of glycaemic control in elderly patients with DM2 should be individualised according to their biopsychosocial characteristics. In elderly patients for whom the benefits of intensive antidiabetic treatment are limited, the basic objectives should be to improve the quality of life, preserve functionality and avoid adverse effects, especially hypoglycaemia.Treatment of DM2 in the elderly was the subject of a consensus document published in 2012 and endorsed by several Spanish scientific societies. Since then, new therapeutic groups and evidence have emerged that warrant an update to this consensus document. The present document focuses on the therapeutic aspects of DM2 in elderly patients, understood as being older than 75 years or frail. 相似文献
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33.
Anthony Dobi Susana B. Bravo Bryan Veeren Beatriz Paradela-Dobarro Ezequiel Álvarez Olivier Meilhac 《Free radical research》2019,53(2):150-169
Advanced glycation end-products (AGEs) trigger multiple metabolic disorders in the vessel wall that may in turn lead to endothelial dysfunction. The molecular mechanisms by which AGEs generate these effects are not completely understood. Oxidative stress plays a key role in the development of deleterious effects that occur in endothelium during diabetes. Our main objectives were to further understand how AGEs contribute to reactive oxygen species (ROS) overproduction in endothelial cells and to evaluate the protective effect of an antioxidant plant extract. The human endothelial cell line EA.hy926 was treated with native or modified bovine serum albumin (respectively BSA and BSA-AGEs). To monitor free radicals formation, we used H2DCF-DA, dihydroethidium (DHE), DAF-FM-DA and MitoSOX Red dyes. To investigate potential sources of ROS, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and mitochondrial inhibitors were used. The regulation of different types of ROS by the polyphenol-rich extract from the medicinal plant Doratoxylon apetalum was also studied for a therapeutic perspective. BSA-AGEs exhibited not only less antioxidant properties than BSA, but also pro-oxidant effects. The degree of albumin glycoxidation directly influenced oxidative stress through a possible communication between NADPH oxidase and mitochondria. D. apetalum significantly decreased intracellular hydrogen peroxide and superoxide anions mainly detected by H2DCF-DA and DHE respectively. Our results suggest that BSA-AGEs promote a marked oxidative stress mediated at least by NADPH oxidase and mitochondria. D. apetalum plant extract appeared to be an effective antioxidant compound to protect endothelial cells. 相似文献
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35.
Direct sequencing of the mitochondrial displacement loop (D-loop) of shrews
(genus Sorex) for the region between the tRNA(Pro) and the conserved
sequence block-F revealed variable numbers of 79-bp tandem repeats. These
repeats were found in all 19 individuals sequenced, representing three
subspecies and one closely related species of the masked shrew group (Sorex
cinereus cinereus, S. c. miscix, S. c. acadicus, and S. haydeni) and an
outgroup, the pygmy shrew (S. hoyi). Each specimen also possessed an
adjacent 76-bp imperfect copy of the tandem repeats. One individual was
heteroplasmic for length variants consisting of five and seven copies of
the 79-bp tandem repeat. The sequence of the repeats is conducive to the
formation of secondary structure. A termination-associated sequence is
present in each of the repeats and in a unique sequence region 5' to the
tandem array as well. Mean genetic distance between the masked shrew taxa
and the pygmy shrew was calculated separately for the unique sequence
region, one of the tandem repeats, the imperfect repeat, and these three
regions combined. The unique sequence region evolved more rapidly than the
tandem repeats or the imperfect repeat. The small genetic distance between
pairs of tandem repeats within an individual is consistent with a model of
concerted evolution. Repeats are apparently duplicated and lost at a high
rate, which tends to homogenize the tandem array. The rate of D- loop
sequence divergence between the masked and pygmy shrews is estimated to be
15%-20%/Myr, the highest rate observed in D-loops of mammals. Rapid
sequence evolution in shrews may be due either to their high metabolic rate
and short generation time or to the presence of variable numbers of tandem
repeats.
相似文献
36.
David Julian Arias-Chávez Patrick Mailloux-Salinas Jessica Ledesma Aparicio Elihu Campos-Pérez Omar Noel Medina-Campos José Pedraza-Chaverri Guadalupe Bravo 《Journal of cellular and molecular medicine》2023,27(20):3147-3156
Benign prostatic hyperplasia (BPH) is the most common adenoma in old men. Tomatoes are a rich source of bioactive compounds that, as well as selenium (Se), possess antioxidant and antiproliferative activity. The aim was to evaluate the therapeutic effect of Se in combination with a tomato extract in aged rats with BPH. Aged male Wistar rats were divided in the following groups (n = 10 rats/group): Control (C), BPH, BPH + Finasteride (BPH + F), BPH + Tomato Lipidic Extract (BPH + E), BPH + Selenium (BPH + S) and BPH plus E plus S (BPH + E + S). After 4 weeks of treatment, prostate weight, diuresis, antioxidants enzymes, prooxidants and inflammatory markers, growth factors and androgens were determined. BPH + E + S reduced prostate weight by 59.29% and inhibited growth by 99.35% compared to BPH + F which only decreased weight and inhibited growth by 15.31% and 57.54%, respectively. Prooxidant markers were higher with BPH + F (49.4% higher vs. BPH), but BPH + E + S decreased these markers (94.27% vs. BPH) and increased antioxidant activity. Finally, diuresis was higher with the BPH + E + S combination and markers of inflammation and growth factors were significantly lower with respect to BPH + F. Our findings provide a beneficial and protective therapeutic option of E + S directed against androgens, oxidative stress and inflammation that regulates cell proliferation in the prostate gland. 相似文献
37.
Beatriz Fernndez‐Marín Javier Gulías Carlos M. Figueroa Concepcin Iiguez María J. Clemente‐Moreno Adriano Nunes‐Nesi Alisdair R. Fernie Lohengrin A. Cavieres Len A. Bravo Jos I. García‐Plazaola Jorge Gago 《The Plant journal : for cell and molecular biology》2020,101(4):979-1000
In this work, we review the physiological and molecular mechanisms that allow vascular plants to perform photosynthesis in extreme environments, such as deserts, polar and alpine ecosystems. Specifically, we discuss the morpho/anatomical, photochemical and metabolic adaptive processes that enable a positive carbon balance in photosynthetic tissues under extreme temperatures and/or severe water‐limiting conditions in C3 species. Nevertheless, only a few studies have described the in situ functioning of photoprotection in plants from extreme environments, given the intrinsic difficulties of fieldwork in remote places. However, they cover a substantial geographical and functional range, which allowed us to describe some general trends. In general, photoprotection relies on the same mechanisms as those operating in the remaining plant species, ranging from enhanced morphological photoprotection to increased scavenging of oxidative products such as reactive oxygen species. Much less information is available about the main physiological and biochemical drivers of photosynthesis: stomatal conductance (gs), mesophyll conductance (gm) and carbon fixation, mostly driven by RuBisCO carboxylation. Extreme environments shape adaptations in structures, such as cell wall and membrane composition, the concentration and activation state of Calvin–Benson cycle enzymes, and RuBisCO evolution, optimizing kinetic traits to ensure functionality. Altogether, these species display a combination of rearrangements, from the whole‐plant level to the molecular scale, to sustain a positive carbon balance in some of the most hostile environments on Earth. 相似文献
38.
Sara Garcia‐Serrano Carolina Gutiérrez‐Repiso Montserrat Gonzalo Juan Garcia‐Arnes Sergio Valdes Federico Soriguer Vidal Perez‐Valero Miguel A. Alaminos‐Castillo Juan Francisco Cobos‐Bravo Francisco J. Moreno‐Ruiz Alberto Rodriguez‐Cañete Francisca Rodríguez‐Pacheco Eva Garcia‐Escobar Eduardo García‐Fuentes 《Obesity (Silver Spring, Md.)》2015,23(8):1607-1615
39.
María José Parra Karina I. Acu?a Angela Sierra-Almeida Camila Sanfuentes Alfredo Salda?a Luis J. Corcuera León A. Bravo 《PloS one》2015,10(12)
Some epiphytic Hymenophyllaceae are restricted to lower parts of the host (<60 cm; 10–100 μmol photons m-2 s-1) in a secondary forest of Southern Chile; other species occupy the whole host height (≥10 m; max PPFD >1000 μmol photons m-2 s-1). Our aim was to study the photosynthetic light responses of two Hymenophyllaceae species in relation to their contrasting distribution. We determined light tolerance of Hymenoglossum cruentum and Hymenophyllum dentatum by measuring gas exchange, PSI and PSII light energy partitioning, NPQ components, and pigment contents. H. dentatum showed lower maximum photosynthesis rates (Amax) than H. cruentum, but the former species kept its net rates (An) near Amax across a wide light range. In contrast, in the latter one, An declined at PPFDs >60 μmol photons m-2 s-1. H. cruentum, the shadiest plant, showed higher chlorophyll contents than H. dentatum. Differences in energy partitioning at PSI and PSII were consistent with gas exchange results. H. dentatum exhibited a higher light compensation point of the partitioning of absorbed energy between photochemical Y(PSII) and non-photochemical Y(NPQ) processes. Hence, both species allocated energy mainly toward photochemistry instead of heat dissipation at their light saturation points. Above saturation, H. cruentum had higher heat dissipation than H. dentatum. PSI yield (YPSI) remained higher in H. dentatum than H. cruentum in a wider light range. In both species, the main cause of heat dissipation at PSI was a donor side limitation. An early dynamic photo-inhibition of PSII may have caused an over reduction of the Qa+ pool decreasing the efficiency of electron donation to PSI. In H. dentatum, a slight increase in heat dissipation due to acceptor side limitation of PSI was observed above 300 μmol photons m-2s-1. Differences in photosynthetic responses to light suggest that light tolerance and species plasticity could explain their contrasting vertical distribution. 相似文献
40.
Bravo E Cantafora A Cicchini C Avella M Botham KM 《Biochimica et biophysica acta》1999,1437(3):367-377
Both estrogen and dietary n-3 polyunsaturated fatty acids are known to be hypocholesterolemic, but appear to exert their effects by different mechanisms. In this study, the interaction between dietary fish oil (rich in n-3 polyunsaturated fatty acids) and estrogen in the regulation of hepatic cholesterol metabolism and biliary lipid secretion in rats was studied. Rats fed a low fat or a fish oil-supplemented diet for 21 days were injected with 17alpha-ethinyl estradiol (5 mg/kg body weight) or the vehicle only (control rats) once per day for 3 consecutive days. Estrogen-treatment led to a marked reduction in plasma cholesterol levels in fish oil-fed rats, which was greater than that observed with either estrogen or dietary fish oil alone. The expression of mRNA for cholesterol 7alpha-hydroxylase was decreased by estrogen in rats fed a low fat or a fish oil-supplemented diet, while the output of cholesterol (micromol/h/kg b.wt.) in the bile was unchanged in both groups. Cholesterol levels in the liver were increased by estrogen in rats given either diet, but there was a significant shift from cholesterol esterification to cholesteryl ester hydrolysis only in the fish oil-fed animals. Estrogen increased the concentration of cholesterol (micromol/ml) in the bile in rats fed the fish oil, but not the low fat diet. However, the cholesterol saturation index was unaffected. The output and concentration of total bile acid was also unaffected, but changes in the distribution of the individual bile acids were observed with estrogen treatment in both low fat and fish oil-fed groups. These results show that interaction between estrogen-treatment and dietary n-3 polyunsaturated fatty acids causes changes in hepatic cholesterol metabolism and biliary lipid secretion in rats, but does not increase the excretion of cholesterol from the body. 相似文献