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101.
《Somatosensory & motor research》2013,30(2):61-66
AbstractThis study aimed to investigate the influence of three stimulating surfaces based on center of pressure (CoP), anteroposterior sway velocity (VA/P), and medio-lateral sway velocity (VM/L) of 40 elderly subjects. CoP and VM/L showed a significant decrease in all visual conditions only in the stimulating surface whereas VA/P showed a significant decrease only on the same surface with eyes open. Results confirm the importance of multisensory stimulation in postural control in the elderly. 相似文献
102.
Masao Fujimoto Akira Kuninaka Hiroshi Yoshino 《Bioscience, biotechnology, and biochemistry》2013,77(10):1991-1997
The inhibitory action of compressed hydrocarbon gases on the growth of the yeast Saccharomyces cerevisiae was investigated quantitatively by microcalorimetry. Both the 50% inhibitory pressure (IP50) and the minimum inhibitory pressure (MIP), which are regarded as indices of the toxicity of hydrocarbon gases, were determined from growth thermograms. Based on these values, the inhibitory potency of the hydrocarbon gases increased in the order methane << ethane < propane < i-butane < n-butane. The toxicity of these hydrocarbon gases correlated to their hydrophobicity, suggesting that hydrocarbon gases interact with some hydrophobic regions of the cell membrane. In support of this, we found that UV absorbing materials at 260 nm were released from yeast cells exposed to compressed hydrocarbon gases. Additionally, scanning electron microscopy indicated that morphological changes occurred in these cells. 相似文献
103.
Milagro Mottola Natalia Wilke Luciano Benedini Rafael Gustavo Oliveira Maria Laura Fanani 《生物化学与生物物理学报:生物膜》2013
Ascorbyl palmitate (ASC16) is an anionic amphiphilic molecule of pharmacological interest due to its antioxidant properties. We found that ASC16 strongly interacted with model membranes. ASC16 penetrated phospholipid monolayers, with a cutoff near the theoretical surface pressure limit. The presence of a lipid film at the interface favored ASC16 insertion compared with a bare air/water surface. The adsorption and penetration time curves showed a biphasic behavior: the first rapid peak evidenced a fast adsorption of charged ASC16 molecules to the interface that promoted a lowering of surface pH, thus partially neutralizing and compacting the film. The second rise represented an approach to the equilibrium between the ASC16 molecules in the subphase and the surface monolayer, whose kinetics depended on the ionization state of the film. Based on the Langmuir dimiristoylphosphatidylcholine + ASC16 monolayer data, we estimated an ASC16 partition coefficient to dimiristoylphosphatidylcholine monolayers of 1.5 × 105 and a ΔGp = − 6.7 kcal·mol− 1. The rheological properties of the host membrane were determinant for ASC16 penetration kinetics: a fluid membrane, as provided by cholesterol, disrupted the liquid-condensed ASC16-enriched domains and favored ASC16 penetration. Subphase pH conditions affected ASC16 aggregation in bulk: the smaller structures at acidic pHs showed a faster equilibrium with the surface film than large lamellar ones. Our results revealed that the ASC16 interaction with model membranes has a highly complex regulation. The polymorphism in the ASC16 bulk aggregation added complexity to the equilibrium between the surface and subphase form of ASC16, whose understanding may shed light on the pharmacological function of this drug. 相似文献
104.
Few species of plant‐parasitic nematodes (PPN) are currently recognised as invasive but this is largely because of insufficient investigation and recognition. We compared the characteristics of PPN with those of invasive species generally, using the propagule pressure, abiotic and biotic factors (PAB) framework. Most PPN had many of the characteristics of invasive species and hence have the potential to become invasive. The most common characteristics included: adaptations for human mediated dispersal; multiple entry pathways; microscopic size; large number of propagules; high fecundity; many or cosmopolitan hosts; short lifecycle; ability to survive harsh or unfavourable conditions; ability to vary sex ratios; and ability to overcome host plant resistance. Information is lacking for many characteristics of many species and their impacts remain unquantified, which leaves some important unanswered questions and challenges for assessing PPN as invasive species. However many economically important PPN species have not been recognised as invasive, even when most of the known characteristics and data suggests they should be. 相似文献
105.
《Channels (Austin, Tex.)》2013,7(1):35-43
As exceptionally calcium selective store-operated channels, Orai channels play a prominent role in cellular calcium signaling. While most studied in the immune system, we are beginning to recognize that Orai1 provides unique calcium signaling pathways in numerous tissue contexts. To assess the involvement of Orai1 in cardiac hypertrophy we used transverse aortic constriction to model pressure overload cardiac hypertrophy and heart failure in Orai1 deficient mice. We demonstrate that Orai1 deficient mice have significantly decreased survival in this pressure overload model. Transthoracic echocardiography reveals that Orai1 deficient mice develop rapid dilated cardiomyopathy, with greater loss of function, and histological and molecular data indicate that this pathology is associated with significant apoptosis, but not major differences in cellular hypertrophy, fibrosis, and some major hypertrophic makers. Orai1 represents a crucial calcium entry mechanism in the compensation of the heart to pressure overload over-load, and the development of dilated cardiomyopathy. 相似文献
106.
Kathrin Schüller Dominik Bühler Nikolaus Plesnila 《Journal of visualized experiments : JoVE》2013,(81)
In this video publication a standardized mouse model of subarachnoid hemorrhage (SAH) is presented. Bleeding is induced by endovascular Circle of Willis perforation (CWp) and proven by intracranial pressure (ICP) monitoring. Thereby a homogenous blood distribution in subarachnoid spaces surrounding the arterial circulation and cerebellar fissures is achieved. Animal physiology is maintained by intubation, mechanical ventilation, and continuous on-line monitoring of various physiological and cardiovascular parameters: body temperature, systemic blood pressure, heart rate, and hemoglobin saturation. Thereby the cerebral perfusion pressure can be tightly monitored resulting in a less variable volume of extravasated blood. This allows a better standardization of endovascular filament perforation in mice and makes the whole model highly reproducible. Thus it is readily available for pharmacological and pathophysiological studies in wild type and genetically altered mice. 相似文献
107.
D. Liendo I. Biurrun J. A. Campos M. Herrera I. García-Mijangos 《Plant biosystems》2013,147(2):289-297
The riparian flora and the level of invasion in the rivers of the Cantabric watershed in Spain were studied in relation to the ecological status and the anthropogenic pressure. The level of invasion was also analyzed in different riparian habitats: forests, river bars and man-made slopes. For this purpose, 18 sites were sampled and a list of native and alien plant species was made along a 100-m strip at each site. The habitat/s where alien species were found and their abundance per habitat and in the total area were also indicated. Out of 112 alien taxa found, 51 were classified as invasive. Exotic plants native to America were the most common (35%). The level of invasion was significantly higher in the sampling sites subject to high levels of hydrological and morphological disturbances, proxies of the anthropogenic pressure. River bars and man-made slopes supported similar number of alien plant species, higher than forests. We suggest that disturbance in river banks should be minimized as much as possible in order to diminish the risk of invasion. 相似文献
108.
Thomas Schmiedinger Georg F. Vogel Oliver Eiter Kristian Pfaller Walter A. Kaufmann Angelika Flörl Karin Gutleben Sabine Schönherr Barbara Witting Thomas W. Lechleitner Hannes‐L. Ebner Thomas Seppi Michael W. Hess 《Traffic (Copenhagen, Denmark)》2013,14(8):886-894
Electrospun nanofibres are an excellent cell culture substrate, enabling the fast and non‐disruptive harvest and transfer of adherent cells for microscopical and biochemical analyses. Metabolic activity and cellular structures are maintained during the only half a minute‐long harvest and transfer process. We show here that such samples can be optimally processed by means of cryofixation combined either with freeze‐substitution, sample rehydration and cryosection‐immunolabelling or with freeze‐fracture replica‐immunolabelling. Moreover, electrospun fibre substrates are equally suitable for complementary approaches, such as biochemistry, fluorescence microscopy and cytochemistry. 相似文献
109.
《Free radical research》2013,47(3-6):353-360
Positive structural identification of the PBN-trichloromethyl spin adduct in vim was accomplished with the use of high pressure liquid chromatography and/or gas chromatography coupled with mass spectrome-try. Both thin layer and liquid chromatography were used to separate a complex mixture of compounds from rat liver extracts treated with CCI, in vitro and in vivo. Deuterated PBN's (PBN-d, text-butyl deuteration, or PBN-d14; both phenyl and tert-butyl deuteration) were also used to aid in the mass spectral analysis of spin adducts from liver extracts of CCI, exposed rat livers, since the rerr-butyl group fragment ion, C4D9+ (m/z = 66) is always present for PBN and PBN spin adducts. In addition, the masses of the ion peaks increase by the amount of deuteration, i.e. an increase of 9 for PBN-d, or PBN-d14 in comparison to normally synthesized PBN. 相似文献
110.