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991.
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993.
Ancelmo Rabelo de Souza Ana Luísa Silva Sampaio Moreira da Costa Demonte Karina de Araujo Costa Mariana Alcantara Cardoso Faria Ricardo Durães-Carvalho Marcelo Lancellotti Carlos Francisco Sampaio Bonafe 《Applied microbiology and biotechnology》2013,97(16):7417-7425
Mycobacterium abscessus is an important hospital-acquired pathogen involved in infections associated with medical, surgical, and biopharmaceutical materials. In this work, we investigated the pressure-induced inactivation of two strains [2544 and American Type Culture Collection (ATCC) 19977] of M. abscessus in combination with different temperatures and pH conditions. For strain 2544, exposure to 250 MPa for 90 min did not significantly inactivate the bacteria at 20 °C, whereas at ?15 °C, there was complete inactivation. Exposure to 250 MPa at ≥60 °C caused rapid inactivation, with no viable bacteria after 45 min. With 45 min of exposure, there were no viable bacteria at any temperature when a higher pressure (350 MPa) was used. Extremes of pH (4 or 9) also markedly enhanced the pressure-induced inactivation of bacteria at 250 MPa, with complete inactivation after 45 min. In comparison, exposure of this strain to the disinfecting agent glutaraldehyde (0.5 %) resulted in total inactivation within 5 min. Strain 19977 was more sensitive to high pressure but less sensitive to glutaraldehyde than strain 2544. These results indicate that high hydrostatic pressure in combination with other physical parameters may be useful in reducing the mycobacterial contamination of medical materials and pharmaceuticals that are sensitive to autoclaving. 相似文献
994.
Sarai Belchí-Navarro Lorena Almagro Ana Belén Sabater-Jara Francisco Fernández-Pérez Roque Bru Maria Angeles Pedreño 《Journal of plant physiology》2013
Suspension-cultured cells of Vitis vinifera cv Monastrell were used to investigate the effects of methyljasmonate, ethylene and salicylic acid separately or in combination with cyclodextrins on both trans-resveratrol production and the induction of defense responses. 相似文献
995.
Arbuscular mycorrhizal symbiosis influences strigolactone production under salinity and alleviates salt stress in lettuce plants 总被引:1,自引:0,他引:1
Ricardo Aroca Juan Manuel Ruiz-Lozano Ángel María Zamarreño José Antonio Paz José María García-Mina María José Pozo Juan Antonio López-Ráez 《Journal of plant physiology》2013
Arbuscular mycorrhizal (AM) symbiosis can alleviate salt stress in plants. However the intimate mechanisms involved, as well as the effect of salinity on the production of signalling molecules associated to the host plant-AM fungus interaction remains largely unknown. In the present work, we have investigated the effects of salinity on lettuce plant performance and production of strigolactones, and assessed its influence on mycorrhizal root colonization. Three different salt concentrations were applied to mycorrhizal and non-mycorrhizal plants, and their effects, over time, analyzed. Plant biomass, stomatal conductance, efficiency of photosystem II, as well as ABA content and strigolactone production were assessed. The expression of ABA biosynthesis genes was also analyzed. 相似文献
996.
Rafael Bielza Galindo Alejandro Ortiz Espada Estefanía Arias Muñana Rocío Velasco Guzmán de Lázaro Asunción Mora Casado Ricardo Moreno Martín Blanca Tapia Salinas Javier Escalera Alonso Jorge Gómez Cerezo 《Revista espa?ola de geriatría y gerontología》2013
Background
Patients with hip fracture (HF), due to their characteristics, require a specific support. The Acute Orthogeriatric Unit (OGU) has been shown to be one of the most beneficial.Objective
To evaluate the main variables of HF patients treated at an OGU and compare them with the previous referral model (RC).Material and methods
A prospective observational study with retrospective control was conducted on 169 patients, split into two groups. In the RC group, patients were admitted to conventional trauma ward. In the OGU group, an early geriatric assessment was performed, and patients were simultaneously attended daily by the orthopaedic surgeon, nurse and geriatrician, and the surgery times, work load, discharge and destination, were planned in a weekly meeting with the rest of professionals.Results
A total of 71 patients were included in the RC group and 96 in the OGU group. The preoperative characteristics were similar, except for a slightly higher comorbidity in the OGU group. The OGU patients were operated on earlier (3.82±2.08 vs 4.61±2.5 days; P<.32), and overall hospital stay was reduced by 28% (11.84±4.04 vs 16.46±8.4 days; P<.001). The functional efficiency (Barthel Index at discharge-Barthel Index at admission/overall stay - stay before surgery) was higher in the OGU group (1.56±0.7 vs 2.61±1.1; P<.05). There were no differences in functional status, mortality or discharge location.Conclusions
The OGU is a level of care that provides effective medical care in HF patients in general hospitals. 相似文献997.
Amanda V. Steckert Samira S. Valvassori Roger B. Varela Francielle Mina Wilson R. Resende Daniela V. Bavaresco Felipe Ornell Felipe Dal-Pizzol João Quevedo 《Neurochemistry international》2013
Several evidences have demonstrated that oxidative stress has a central role in bipolar disorder (BD). Recently, studies have been suggested histone deacetylases (HDAC) as a possible target for new medications in treatment of mood disorders. In this study, we investigated the effects of sodium butyrate (SB, a histone deacetilase inhibitor) on oxidative stress in rats submitted to an animal model of mania induced by d-amphetamine (d-AMPH). Wistar rats were first given d-AMPH or saline (Sal) for 14 days, and then, between days 8 and 14, rats were treated with SB or Sal. Locomotor activity and risk-taking behavior were assessed by open-field test and oxidative stress was measured in prefrontal cortex, amygdala, hippocampus and striatum. The results showed that SB reversed and prevented d-AMPH-induced behavioral effects. The d-AMPH administration induced oxidative damage in all brain structures analyzed. Depending on the cerebral area and technique, SB was able to reverse this impairment. The present study reinforces the need for more studies of HDAC inhibitors as possible target for new medications in treatment for BD. 相似文献
998.
Fernanda Luna da Silva Eduardo Coelho Cerqueira Mônica Santos de Freitas Daniela Leão Gonçalves Lilian Terezinha Costa Cristian Follmer 《Neurochemistry international》2013
In the last decades, a series of compounds, including quinones and polyphenols, has been described as having anti-fibrillogenic action on α-synuclein (α-syn) whose aggregation is associated to the pathogenesis of Parkinson’s disease (PD). Most of these molecules act as promiscuous anti-amyloidogenic agents, interacting with the diverse amyloidogenic proteins (mostly unfolded) through non-specific hydrophobic interactions. Herein we investigated the effect of the vitamins K (phylloquinone, menaquinone and menadione), which are 1,4-naphthoquinone (1,4-NQ) derivatives, on α-syn aggregation, comparing them with other anti-fibrillogenic molecules such as quinones, polyphenols and lipophilic vitamins. Vitamins K delayed α-syn fibrillization in substoichiometric concentrations, leading to the formation of short, sheared fibrils and amorphous aggregates, which are less prone to produce leakage of synthetic vesicles. In seeding conditions, menadione and 1,4-NQ significantly inhibited fibrils elongation, which could be explained by their ability to destabilize preformed fibrils of α-syn. Bidimensional NMR experiments indicate that a specific site at the N-terminal α-syn (Gly31/Lys32) is involved in the interaction with vitamins K, which is corroborated by previous studies suggesting that Lys is a key residue in the interaction with quinones. Together, our data suggest that 1,4-NQ, recently showed up by our group as a potential scaffold for designing new monoamine oxidase inhibitors, is also capable to modulate α-syn fibrillization in vitro. 相似文献
999.
Joël Broyer 《Bird Study》2013,60(2):141-150
Capsule Mowing postponement in 25% of a meadow system may lead to improved but instable population dynamics in meadow birds. Aim To monitor the long‐term effects of mowing postponement on the abundance and territory density of meadow passerines in 25% of a 3000‐ha hay‐meadow area in the Saône Valley (eastern France). Methods From 1993 to 2009, passerine abundance was measured annually in 78 plots using point counts and territory density was assessed in two study areas by Territory Mapping. Results The programme of mowing postponement led to substantially increased passerine abundance and territory density, with the highest increase detected in Whinchats Saxicola rubetra. No positive trend was observed in Corn Buntings Emberiza calandra. Immediately after the increase in abundance, bird distribution within the study area was not influenced by the timing of mowing. The hatching success, assessed by the systematic observation of food carrying, was negatively influenced by early mowing (<40% recorded when >60% of the meadow area was already harvested on 1 July) or, in late mown areas, by high meadow passerine territory density (<40% when territory density was >10 per 10 ha). Hatching rate was usually higher in Whinchats than in Corn Buntings. Conclusion By improving meadow passerine breeding outputs and density, mowing postponement led to instable population dynamics with dominance of certain species and density‐dependent breeding success. 相似文献
1000.
María Eugenia Sabatino Liliana del Valle Sosa Juan Pablo Petiti Jorge Humberto Mukdsi Iván Darío Mascanfroni Claudia Gabriela Pellizas Silvina Gutiérrez Alicia Inés Torres Ana Lucía De Paul 《Experimental cell research》2013
Toll like receptor 4 (TLR4) has been characterized for its ability to recognize bacterial endotoxin lipopolysaccharide (LPS). Considering that infections or inflammatory processes might contribute to the progression of pituitary tumors, we analyzed the TLR4 functional role by evaluating the LPS effect on lactotroph proliferation in primary cultures from experimental pituitary tumors, and examined the involvement of PI3K-Akt and NF-κB activation in this effect. In addition, the role of 17β-estradiol as a possible modulator of LPS-induced PRL cell proliferation was further investigated. In estrogen-induced hyperplasic pituitaries, LPS triggered lactotroph cell proliferation. However, endotoxin failed to increase the number of lactotrophs taking up BrdU in normal pituitaries. Moreover, incubation with anti-TLR4 antibody significantly reduced LPS-induced lactotroph proliferation, suggesting a functional role of this receptor. As a sign of TLR4 activation, an LPS challenge increased IL-6 release in normal and tumoral cells. By flow cytometry, TLR4 baseline expression was revealed at the plasma membrane of tumoral lactotrophs, without changes noted in the percentage of double PRL/TLR4 positive cells after LPS stimulus. Increases in TLR4 intracellular expression were detected as well as rises in CD14, p-Akt and NF-κB after an LPS challenge, as assessed by western blotting. The TLR4/PRL and PRL/NF-κB co-localization was also corroborated by immunofluorescence and the involvement of PI3K/Akt signaling in lactotroph proliferation and IL-6 release was revealed through the PI3K inhibitor Ly-294002. In addition, 17β-estradiol attenuated the LPS-evoked increase in tumoral lactotroph proliferation and IL-6 release. Collectively these results demonstrate the presence of functional TLR4 in lactotrophs from estrogen-induced hyperplasic pituitaries, which responded to the proliferative stimulation and IL-6 release induced by LPS through TLR4/CD14, with a contribution of the PI3K-Akt and NF-κB signaling pathways. 相似文献