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71.
Layanne Cabral da?Cunha Araujo Iara Le?o?Luna de Souza Luiz Henrique?César Vasconcelos Aline de?Freitas Brito Fernando?Ramos Queiroga Alexandre?Sérgio Silva Patrícia?Mirella da Silva Fabiana de?Andrade Cavalcante Bagnólia?Araújo da Silva 《Bioscience reports》2015,35(5)
Several studies have reported the gastrointestinal (GI) effects promoted by the physical exercise. Thus, we aimed to evaluate the influence of swimming exercise on the contractile reactivity, lipid peroxidation and morphology of rat ileum. Wistar rats were divided into sedentary (SED) and groups exercised for two (EX2), four (EX4), six (EX6) or eight (EX8) weeks, 5 days/week. Animals were killed; the ileum was removed and suspended in organ baths where the isotonic contractions were recorded. Lipid peroxidation was evaluated by MDA (malondialdehyde) measurement with TBARS (thiobarbituric acid reactive substances) assay and morphology by histological staining. Cumulative concentration-response curves to KCl were attenuated, as the Emax values were changed from 100% (SED) to 63.1±3.9 (EX2), 48.8±3.8 (EX4), 19.4±1.8 (EX6) and 59.4±2.8% (EX8). Similarly, cumulative concentration-response curves to carbamylcholine hydrochloride (CCh) were attenuated, as the Emax values were changed from 100% (SED) to 74.1±5.4 (EX2), 75.9±5.2 (EX4) and 62.9±4.6 (EX6), but not in the EX8 (89.7±3.4%). However, CCh potency was increased in this latter, as the EC50 was altered from 1.0±0.1×10−6 (SED) to 2.1±0.4×10−7 (EX8). MDA concentration was altered only in EX4 (44.3±4.4) compared with SED (20.6±3.6 μmol/l). Circular layer was reduced in SED when compared with the exercised groups. Conversely, longitudinal layer was increased. In conclusion, chronic swimming exercise reduces the ileum contraction, equilibrates the oxidative damage and promotes changes in tissue size to establish an adaptation to the exercise. 相似文献
72.
Amelia O. Clive Clare E. Hooper Anthony J. Edey Anna J. Morley Natalie Zahan-Evans David Hall Iain Lyburn Paul White Jeremy P. Braybrooke Iara Sequeiros Stephen M. Lyen Tim Milton Brennan C. Kahan Nick A. Maskell 《PloS one》2015,10(3)
Introduction
Animal studies have shown Zoledronic Acid (ZA) may diminish pleural fluid accumulation and tumour bulk in malignant pleural disease (MPD). We performed a pilot study to evaluate its effects in humans.Methods
We undertook a single centre, double-blind, placebo-controlled trial in adults with MPD. Patients were randomised (1:1) to receive 2 doses of intravenous ZA or placebo, 3 weeks apart and were followed-up for 6 weeks. The co-primary outcomes were change in Visual Analogue Scale (VAS) score measured breathlessness during trial follow-up and change in the initial area under the curve (iAUC) on thoracic Dynamic Contrast Enhanced Magnetic Resonance Imaging (DCE-MRI) from randomisation to week 5. Multiple secondary endpoints were also evaluated.Results
Between January 2010 and May 2013, 30 patients were enrolled, 24 randomised and 4 withdrew after randomisation (1 withdrew consent; 3 had a clinical decline). At baseline, the ZA group were more breathless, had more advanced disease on radiology and worse quality of life than the placebo group. There was no significant difference between the groups with regards change in breathlessness (Adjusted mean difference (AMD) 4.16 (95%CI −4.7 to 13.0)) or change in DCE-MRI iAUC (AMD −15.4 (95%CI −58.1 to 27.3). Two of nine (22%) in the ZA arm had a >10% improvement by modified RECIST (vs 0/11 who received placebo). There was no significant difference in quality of life measured by the QLQ-C30 score (global QOL: AMD -4.1 (-13.0 to 4.9)), side effects or serious adverse event rates.Conclusions
This is the first human study to evaluate ZA in MPD. The study is limited by small numbers and imbalanced baseline characteristics. Although no convincing treatment effect was identified, potential benefits for specific subgroups of patients cannot be excluded. This study provides important information regarding the feasibility of future trials to evaluate the effects of ZA further.Trial Registration
UK Clinical Research Network ID 8877 ISRCTN17030426 www.isrctn.com 相似文献73.
NPFXD-mediated endocytosis is required for polarity and function of a yeast cell wall stress sensor 下载免费PDF全文
The actin-associated protein Sla1p, through its SHD1 domain, acts as an adaptor for the NPFX(1,2)D endocytic targeting signal in yeast. Here we report that Wsc1p, a cell wall stress sensor, depends on this signal-adaptor pair for endocytosis. Mutation of NPFDD in Wsc1p or expression of Sla1p lacking SHD1 blocked Wsc1p internalization. By live cell imaging, endocytically defective Wsc1p was not concentrated at sites of endocytosis. Polarized distribution of Wsc1p to regions of cell growth was lost in the absence of endocytosis. Mutations in genes necessary for endosome to Golgi traffic caused redistribution of Wsc1p from the cell surface to internal compartments, indicative of recycling. Inhibition of Wsc1p endocytosis caused defects in polarized deposition of the cell wall and increased sensitivity to perturbation of cell wall synthesis. Our results reveal that the NPFX(1,2)D-Sla1p system is responsible for directing Wsc1p into an endocytosis and recycling pathway necessary to maintain yeast cell wall polarity. The dynamic localization of Wsc1p, a sensor of the extracellular wall in yeast, resembles polarized distribution of certain extracellular matrix-sensing integrins through endocytic recycling. 相似文献
74.
Tena-Tomás C Pedroso ML de Messias-Reason IJ Kremsner PG Kun JF 《European cytokine network》2007,18(3):136-141
AIMS: Interferon-alpha (IFN-alpha) alone or in combination with ribavirin has been used for the last decade in the treatment of chronic hepatitis C, although the achievement of a sustained virological response (SVR) has not been very satisfactory. The treatment outcome depends on viral genotypes and host genetic polymorphisms in genes involved in the IFN-alpha signaling cascade. In this paper, we investigated the distribution of two variants of the IFNAR1 gene, G17470C and L168V, in two patient groups having received IFN-alpha alone or in combination with ribavirin. METHODS: The analysis was performed using DNA sequencing of the relevant gene fragments. RESULTS AND CONCLUSIONS: This study suggests that when combination therapy with high dose IFN-alpha and ribavirin is administered, HCV genotypes and age rather than the IFNAR1 polymorphisms are the predictors of a sustained response. 相似文献
75.
Inajara Viana Gomes Alzira Kelly Passos Roriz Alexandre Santos Araújo Vanessa Simões Dias Antonio Nascimento Iara Sordi Joachim-Bravo 《Physiological Entomology》2024,49(2):99-109
We analysed the influence of laboratory domestication, under relaxed conditions, on the courtship behaviour of the fruit fly species Anastrepha obliqua, an important agricultural pest. We compared the temporal patterns of pheromone emission (Calling behaviour) and the frequencies and sequences of the courtship behavioural units of males of a laboratory lineage and a wild lineage. Our results indicated similarities in the temporal behavioural patterns of calling, the durations of their behavioural sequences, the final sequences of courtships resulting in copulation, of wild and laboratory males. Differences, however, were observed between the two populations in terms of the frequencies of the behavioural units executed and the initial sequence of courtship. Differences were noted in the presence or absence of some behavioural units within the courtship behavioural repertoires of the laboratory-reared and wild. The wild males did not show units such as Alignment, Contact, Fighting and Marking Leaf that were observed in the laboratory males' courtship behaviour under laboratory conditions; on the other hand, laboratory males did not show the Abdominal movements and Oscillation observed in the courtship behaviour of wild males. The rearing of A. obliqua males under relaxed conditions in the laboratory provides an environment adequate for the preservation of behavioural characteristics relevant to the successful mating, such as Movement, Arrowhead 1, and Attempt, and in temporal patterns of pheromone emission. 相似文献
76.
77.
Characterization of alkaline proteases from a novel alkali-tolerant bacterium Bacillus patagoniensis
Nelda Olivera Cynthia Sequeiros Faustino Siñeriz Javier D. Breccia 《World journal of microbiology & biotechnology》2006,22(7):737-743
Summary The extracellular proteolytic activity produced by a moderately alkaliphilic bacterium, Bacillus patagoniensis PAT 05T, was characterized. This strain, grown in a highly alkaline and saline medium, produced important levels of proteolytic activity.
SDS-PAGE and zymogram analyses revealed two proteolytic active bands. Through isoelectricfocusing (IEF)-zymogram, an active
band with alkaline pI and two slighter active bands with acid pI values were detected. The alkaline active enzyme in the IEF
was purified and characterized. It showed a molecular mass of 29.4 kDa and its pI value was >‰10.3. Proteolytic activity of
the culture supernatant showed an optimal temperature of approximately 60 °C and a plateau of maximum activity between pH
9.0 and 12.0. Such activity was not affected by H2O2 (10% v/v), 1,10-phenanthroline (10 mM), Triton X-100 (1% v/v) and Tween 20 (1% v/v), under the assay conditions. More than
80% of the activity was retained in 10 mM EDTA, 73% in 1 % (w/v) SDS and 63% in 2 M NaCl. The enzyme was inhibited by PMSF,
indicating serine-protease activity. The proteolytic activity of the crude supernatant was thermosensitive with a half-life
of 2.3 min at 70 °C, while high activity was detected at moderate temperatures. Considering PAT 05T proteolytic activity characteristics, such as high optimum pH, high stability and residual activity in presence of oxidant,
surfactant and chelating agents, this strain could be a potential source of enzymes for use as additives in detergent formulations
or in the leather industry. 相似文献
78.
Paula dos Passos Menezes Polliana Barbosa Pereira dos Santos Grace Anne Azevedo Dória Bruna Maria Hipólito de Sousa Mairim Russo Serafini Paula Santos Nunes Lucindo José Quintans-Júnior Iara Lisboa de Matos Péricles Barreto Alves Daniel Pereira Bezerra Francisco Jaime Bezerra Mendonça Júnior Gabriel Francisco da Silva Thiago Mendonça de Aquino Edson de Souza Bento Marcus Tullius Scotti Luciana Scotti Adriano Antunes de Souza Araujo 《AAPS PharmSciTech》2017,18(1):49-57
This study evaluated three different methods for the formation of an inclusion complex between alpha- and beta-cyclodextrin (α- and β-CD) and limonene (LIM) with the goal of improving the physicochemical properties of limonene. The study samples were prepared through physical mixing (PM), paste complexation (PC), and slurry complexation (SC) methods in the molar ratio of 1:1 (cyclodextrin:limonene). The complexes prepared were evaluated with thermogravimetry/derivate thermogravimetry, infrared spectroscopy, X-ray diffraction, complexation efficiency through gas chromatography/mass spectrometry analyses, molecular modeling, and nuclear magnetic resonance. The results showed that the physical mixing procedure did not produce complexation, but the paste and slurry methods produced inclusion complexes, which demonstrated interactions outside of the cavity of the CDs. However, the paste obtained with β-cyclodextrin did not demonstrate complexation in the gas chromatographic technique because, after extraction, most of the limonene was either surface-adsorbed by β-cyclodextrin or volatilized during the procedure. We conclude that paste complexation and slurry complexation are effective and economic methods to improve the physicochemical character of limonene and could have important applications in pharmacological activities in terms of an increase in solubility. 相似文献
79.
Jordan T. McEwen Iara M. P. Machado Michael R. Connor Shota Atsumi 《Applied and environmental microbiology》2013,79(5):1668-1675
Synechococcus elongatus strain PCC 7942 strictly depends upon the generation of photosynthetically derived energy for growth and is incapable of biomass increase in the absence of light energy. Obligate phototrophs'' core metabolism is very similar to that of heterotrophic counterparts exhibiting diverse trophic behavior. Most characterized cyanobacterial species are obligate photoautotrophs under examined conditions. Here we determine that sugar transporter systems are the necessary genetic factors in order for a model cyanobacterium, Synechococcus elongatus PCC 7942, to grow continuously under diurnal (light/dark) conditions using saccharides such as glucose, xylose, and sucrose. While the universal causes of obligate photoautotrophy may be diverse, installing sugar transporters provides new insight into the mode of obligate photoautotrophy for cyanobacteria. Moreover, cyanobacterial chemical production has gained increased attention. However, this obligate phototroph is incapable of product formation in the absence of light. Thus, converting an obligate photoautotroph to a heterotroph is desirable for more efficient, economical, and controllable production systems. 相似文献
80.
Dr. Antonio Haddad Georges Pelletier Fausto Marchi Iara L. G. Brasileiro 《Cell and tissue research》1977,177(1):67-79
Summary Fucose-3H was injected into the cerebral ventricle of rats that were killed at several time intervals after injection. Semi-thin sections of the supraoptic nucleus and neurohypophysis were processed for radioautography and analysed quantitatively. Silver grains indicating the site of fucose-labeled glycoproteins were first located at the perinuclear region of the secretory neurons. The highest silver-grain density in these cells was observed at 2 h after injection, declining afterwards. Silver grains over the neurohypophysis were observed from 2 h on, reached a peak at 1 day after injection and decreased in the subsequent time intervals. The distributions of the silver grains over the neurohypophysis fitted Poissonian distributions and these were shown to be heterogeneous at the several time intervals. Pituicytes were not labeled. The percentage of silver grains over the Herring bodies increased with time. In rats deprived of water after fucose-3H injection there was a great increase in the release of labeled glycoproteins from the neurohypophysis. These results indicate that the glycoproteins synthesized by the secretory neurons of the hypothalamic nuclei are secreted in the neurohypophysis. 相似文献