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排序方式: 共有334条查询结果,搜索用时 31 毫秒
71.
Eva Román Cristina García-Galcerán Teresa Torrades Silvia Herrera Ana Marín Maite Do?ate Edilmar Alvarado-Tapias Jorge Malouf Laura Nácher Ricard Serra-Grima Carlos Guarner Juan Cordoba German Soriano 《PloS one》2016,11(3)
Patients with cirrhosis often have functional limitations, decreased muscle mass, and a high risk of falls. These variables could improve with exercise. The aim was to study the effects of moderate exercise on functional capacity, body composition and risk of falls in patients with cirrhosis. Twenty-three cirrhotic patients were randomized to an exercise programme (n = 14) or to a relaxation programme (n = 9). Both programmes consisted of a one-hour session 3 days a week for 12 weeks. At the beginning and end of the study, we measured functional capacity using the cardiopulmonary exercise test, evaluated body composition using anthropometry and dual energy X-ray absorptiometry, and estimated risk of falls using the Timed Up&Go test. In the exercise group, cardiopulmonary exercise test showed an increase in total effort time (p<0.001) and ventilatory anaerobic threshold time (p = 0.009). Upper thigh circumference increased and mid-arm and mid-thigh skinfold thickness decreased. Dual energy X-ray absorptiometry showed a decrease in fat body mass (-0.94 kg, 95%CI -0.48 to -1.41, p = 0.003) and an increase in lean body mass (1.05 kg, 95%CI 0.27 to 1.82, p = 0.01), lean appendicular mass (0.38 kg, 95%CI 0.06 to 0.69, p = 0.03) and lean leg mass (0.34 kg, 95%CI 0.10 to 0.57, p = 0.02). The Timed Up&Go test decreased at the end of the study compared to baseline (p = 0.02). No changes were observed in the relaxation group. We conclude that a moderate exercise programme in patients with cirrhosis improves functional capacity, increases muscle mass, and decreases body fat and the Timed Up&Go time.Trial Registration: ClinicalTrials.gov NCT01447537相似文献
72.
Ana Belén Rodríguez-Urra Carlos Jimenez Maite Dueñas & Unai Ugalde 《FEMS microbiology letters》2009,300(2):216-221
A new insertion sequence (IS), IS 1642 , was identified in a Mycobacterium avium strain isolated from a human patient. IS 1642 had a size of 1642 bp and contained a single ORF encoding a probable transposase of 503 amino acid residues homologous (79% identity) to that of IS 1549 found in Mycobacterium smegmatis . The IS 1642 included imperfect inverted repeats (5'-cctgacttttatca-3', 5'-tgataaaagtcggg-3') on its ends, and was flanked by direct repeats of variable length ranging from 5 to 161 bp. It was suggested that the IS 1642 was widely distributed in many M. avium strains of human patients, and the Southern blot profile of IS 1642 was very diverse among the strains examined. The transposition event of IS 1642 was observed by in vitro repeated passages, showing that the IS 1642 is actually a transposable element. In light of these characteristics, IS 1642 could be a new useful marker when genotyping with high discrimination is required. 相似文献
73.
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75.
Santos-Jiménez José Leonardo de Barros Montebianco Caroline Vidal Andreza Henrique G. Ribeiro Simone Barreto-Bergter Eliana Vaslin Maite Freitas Silva 《BioControl》2022,67(1):75-87
BioControl - Passion fruit woodiness disease is responsible for severe losses in passion fruit production around the world. The disease is caused by Cowpea aphid-borne mosaic virus (CABMV), an... 相似文献
76.
Latasa C García B Echeverz M Toledo-Arana A Valle J Campoy S García-del Portillo F Solano C Lasa I 《Journal of bacteriology》2012,194(14):3708-3722
The Rcs phosphorelay pathway is a complex signaling pathway involved in the regulation of many cell surface structures in enteric bacteria. In response to environmental stimuli, the sensor histidine kinase (RcsC) autophosphorylates and then transfers the phosphate through intermediary steps to the response regulator (RcsB), which, once phosphorylated, regulates gene expression. Here, we show that Salmonella biofilm development depends on the phosphorylation status of RcsB. Thus, unphosphorylated RcsB, hitherto assumed to be inactive, is essential to activate the expression of the biofilm matrix compounds. The prevention of RcsB phosphorylation either by the disruption of the phosphorelay at the RcsC or RcsD level or by the production of a nonphosphorylatable RcsB allele induces biofilm development. On the contrary, the phosphorylation of RcsB by the constitutive activation of the Rcs pathway inhibits biofilm development, an effect that can be counteracted by the introduction of a nonphosphorylatable RcsB allele. The inhibition of biofilm development by phosphorylated RcsB is due to the repression of CsgD expression, through a mechanism dependent on the accumulation of the small noncoding RNA RprA. Our results indicate that unphosphorylated RcsB plays an active role for integrating environmental signals and, more broadly, that RcsB phosphorylation acts as a key switch between planktonic and sessile life-styles in Salmonella enterica serovar Typhimurium. 相似文献
77.
Carreras-Aubets M Montero FE Kostadinova A Gibson DI Carrassón M 《Systematic parasitology》2012,82(3):185-199
Two frequently reported but poorly known hemiurid digeneans, Lecithochirium musculus (Looss, 1907) (Lecithochiriinae), from the stomach of Trachinus draco and Citharus linguatula, and Ectenurus lepidus Looss, 1907 (Dinurinae), from the stomach of Spicara maena, are redescribed based on material from off the Barcelona coast of the western Mediterranean. The two species are commented upon, and Lecithochirium israelense Fischthal, 1980 is considered a synonym of L. musculus. Records of the two species in the Mediterranean Basin and North East Atlantic region are summarised. 相似文献
78.
Elías Barquero-Calvo Raquel Conde-Alvarez Carlos Chacón-Díaz Lucía Quesada-Lobo Anna Martirosyan Caterina Guzmán-Verri Maite Iriarte Mateja Mancek-Keber Roman Jerala Jean Pierre Gorvel Ignacio Moriyón Edgardo Moreno Esteban Chaves-Olarte 《PloS one》2009,4(6)
Background
During evolution, innate immunity has been tuned to recognize pathogen-associated molecular patterns. However, some α-Proteobacteria are stealthy intracellular pathogens not readily detected by this system. Brucella members follow this strategy and are highly virulent, but other Brucellaceae like Ochrobactrum are rhizosphere inhabitants and only opportunistic pathogens. To gain insight into the emergence of the stealthy strategy, we compared these two phylogenetically close but biologically divergent bacteria.Methodology/Principal Findings
In contrast to Brucella abortus, Ochrobactrum anthropi did not replicate within professional and non-professional phagocytes and, whereas neutrophils had a limited action on B. abortus, they were essential to control O. anthropi infections. O. anthropi triggered proinflammatory responses markedly lower than Salmonella enterica but higher than B. abortus. In macrophages and dendritic cells, the corresponding lipopolysaccharides reproduced these grades of activation, and binding of O. anthropi lipopolysaccharide to the TLR4 co-receptor MD-2 and NF-κB induction laid between those of B. abortus and enteric bacteria lipopolysaccharides. These differences correlate with reported variations in lipopolysaccharide core sugars, sensitivity to bactericidal peptides and outer membrane permeability.Conclusions/Significance
The results suggest that Brucellaceae ancestors carried molecules not readily recognized by innate immunity, so that non-drastic variations led to the emergence of stealthy intracellular parasites. They also suggest that some critical envelope properties, like selective permeability, are profoundly altered upon modification of pathogen-associated molecular patterns, and that this represents a further adaptation to the host. It is proposed that this adaptive trend is relevant in other intracellular α-Proteobacteria like Bartonella, Rickettsia, Anaplasma, Ehrlichia and Wolbachia. 相似文献79.
Alien plant species, such as Caulerpa racemosa var. cylindracea, that invade Mediterranean marine vegetated habitats can affect habitat structure. In turn, changes in habitat structure
may affect the associated invertebrate assemblages, either through changes in habitat selection or as a result of altered
predation efficiency. In order to test for effects of changes in habitat structure resulting from colonization by C. racemosa on prey availability for predators, the importance of amphipods as a trophic resource in natural vegetated habitat was first
assessed, and later experiments were undertaken to assess the effects of the alien alga on predation by Thalassoma pavo of two dominant amphipods: Elasmopus brasiliensis (Gammaridea) and Caprella dilatata (Caprellidea). Laboratory experiments were conducted in separate aquaria with five vegetation habitat types: Halopteris scoparia, Jania rubens, C. racemosa without detritus, C. racemosa with detritus, Cymodocea nodosa, together with controls. The vegetation was first defaunated, and then 30 amphipods were introduced to each aquarium and
exposed to a single Thalassoma pavo individual for 1 h, after which the fish’s gut contents were examined. Consumption (per fish per hour) of caprellids (11.7 ± 1.4)
was higher overall than that of gammarids (8.7 ± 1.5) and likely reflects different microhabitat use by amphipods, which affects
susceptibility to predators. Consumption of amphipods also varied by habitat type. The highest predation rate was found in
the C. nodosa habitat (12.7 ± 2.19) and the lowest in the C. racemosa habitats with detritus (4.1 ± 1.78) and without detritus (5.2 ± 0.55), which did not differ. The pattern of predation across
habitats, however, was similar for both caprellid and gammarid amphipods, indicating a more general effect of habitat on amphipod
predation. Our findings showed that invasive species such as C. racemosa can decrease feeding by predators such as T. pavo. Changes in predator–prey interactions could have consequences for food web support in the Mediterranean. 相似文献
80.
Symbionts and abnormal conditions of razor clam Ensis arcuatus were surveyed in three commercially important natural beds of Galician estuaries (NW Spain). Samples of 15-20 E. arcuatus were collected every 2 months from January 2003 until July 2004 and processed for histological examination. Prokaryote-like colonies, renal coccidians, gregarines, Trichodina sp. ciliates, haplosporidian-like plasmodia, turbelaria, trematode metacercariae, cestode-like larvae and basophilic inclusion bodies were observed in razor clam tissues without causing host damage. Bucephalid digenean sporocysts and germinoma were seen in some samples causing moderate or severe damage to the host depending on the intensity of infection and both could be a cause for concern if prevalence reached epizootic levels in Galician E. arcuatus populations. None of the parasites detected is OIE notifiable and, in general, the commercially exploited beds studied seem to be devoid of serious pathogens. 相似文献