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991.
Purpose: The main objective of the present study was to evaluate the effects of laterality discrimination training on neck joint position sense and cervical range of motion (ROM) in patients with chronic non-specific neck pain (NSCNP).

Materials and methods: Forty-eight patients with NSCNP were randomly assigned to the neck group (NG) that observed neck images or the foot group (FG) that observed foot images. Response time, response accuracy, cervical ROM, and joint position error (JPE) were the main variables. The secondary outcome measures included psychosocial variables.

Results: Differences between groups in the cervical ROM for flexion (p?=?.043) were obtained, being NG group the one which obtained greater values. NG showed an improvement in right rotation (p?=?.018) and a decrease in flexion was found in the FG (p?=?.039). In JPE, differences between groups were obtained in the left rotation (p?=?.021) and significant changes were found in the NG for flexion, extension, and left rotation movements (p?<?.05). Moderate associations were found between left and right accuracy regarding to post-intervention flexion and right rotation (r?=?0.46, r?=?0.41; p?<?.05) in NG.

Conclusion: Improvements in cervical range of motion and joint position sense are obtained after the performance of the laterality discrimination task of images of the neck but not the feet. Visualization of images of the painful region presents moderate correlations with the accuracy and response time in the movements of flexion and right rotation.  相似文献   

992.
Plants exposed to hostile environmental conditions such as drought or extreme temperatures usually undergo oxidative stress, which has long been assumed to significantly contribute to the damage suffered by the organism. Reactive oxygen species (ROS) overproduced under stress conditions were proposed to destroy membrane lipids and to inactivate proteins and photosystems, ultimately leading to cell death. Accordingly, considerable effort has been devoted, over the years, to improve stress tolerance by strengthening antioxidant and dissipative mechanisms. Although the notion that ROS cause indiscriminate damage in vivo has been progressively replaced by the alternate concept that they act as signaling molecules directing critical plant developmental and environmental responses including cell death, the induction of genes encoding antioxidant activities is commonplace under many environmental stresses, suggesting that their manipulation still offers promise. The features and consequences of ROS effects depend on the balance between various interacting pathways including ROS synthesis and scavenging, energy dissipation, conjugative reactions, and eventually reductive repair. They represent many possibilities for genetic manipulation. We report, herein, a comprehensive survey of transgenic plants in which components of the ROS-associated pathways were overexpressed, and of the stress phenotypes displayed by the corresponding transformants. Genetic engineering of different stages of ROS metabolism such as synthesis, scavenging, and reductive repair revealed a strong correlation between down-regulation of ROS levels and increased stress tolerance in plants grown under controlled conditions. Field assays are scarce, and are eagerly required to assess the possible application of this strategy to agriculture.  相似文献   
993.
994.
We aimed to study the fecundity and reproductive investment of Loxopagurus loxochelis under different environmental conditions. In total, 67 ovigerous females were analyzed, 20 from Macaé, 26 from Ubatuba and 21 from Cananéia. The cephalothoracic shield length, fecundity and reproductive investment (Ubatuba 10.2%, Macaé 8.9% and Cananéia 7.5%) were different among the regions (ANCOVA, p < 0.05), caused by different abiotic resources and environmental characteristics found in each sampling region. Cananéia had the smallest individuals and low availability of adequate shells to hermit crabs, a condition that may have affected the growth and reproduction of the animals. Macaé has a continuous transport of nutrients such as nitrogen and phosphorus to the surface promoted by the Cabo Frio Upwelling zone, which may be a favourable condition for plankton production and, consequently, the extended ‘match/mismatch’ adjustment of spawning females of L. loxochelis. We propose that the highest reproductive investment on the Ubatuba coast is a consequence of regional environmental scenarios of waters colder than the Cananéia region, i.e. females concentrate more energy to reproduce seasonally. Thus, we proved that patterns of L. loxochelis’ reproduction can change on a regional scale according to the local condition of shell supply and water temperature.  相似文献   
995.
Journal of Plant Growth Regulation - The potential of microalgae as a biofertilizer in agriculture is increasingly recognized. We studied the effect of applications of Chlorella on growth of wheat...  相似文献   
996.
997.
Damage associated molecular patterns (DAMPs) are released form red blood cells (RBCs) during intravascular hemolysis (IVH). Extracellular heme, with its pro-oxidant, pro-inflammatory and cytotoxic effects, is sensed by innate immune cells through pattern recognition receptors such as toll-like receptor 4 and nucleotide-binding domain and leucine rich repeat containing family, pyrin domain containing 3 (NLRP3), while free availability of heme is strictly controlled. Here we investigated the involvement of different hemoglobin (Hb) forms in hemolysis-associated inflammatory responses.We found that after IVH most of the extracellular heme molecules are localized in oxidized Hb forms. IVH was associated with caspase-1 activation and formation of mature IL-1β in plasma and in the liver of C57BL/6 mice. We showed that ferrylHb (FHb) induces active IL-1β production in LPS-primed macrophages in vitro and triggered intraperitoneal recruitment of neutrophils and monocytes, caspase-1 activation and active IL-1β formation in the liver of C57BL/6 mice. NLRP3 deficiency provided a survival advantage upon IVH, without influencing the extent of RBC lysis or the accumulation of oxidized Hb forms. However, both hemolysis-induced and FHb-induced pro-inflammatory responses were largely attenuated in Nlrp3?/? mice.Taken together, FHb is a potent trigger of NLRP3 activation and production of IL-1β in vitro and in vivo, suggesting that FHb may contribute to hemolysis-induced inflammation. Identification of RBC-derived DAMPs might allow us to develop new therapeutic approaches for hemolytic diseases.  相似文献   
998.
The role of protein kinase C (PKC) on muscarinic regulation of serotonin release in the pineal gland was investigated by measuring the pineal-PKC activity and serotonin secretion in response to muscarinic agents. Pineal slices, short-term incubated (0-15 min) without additions produced a low serotonin release and 20 to 24 percent PKC activity was found associated with membrane fractions. Prolonged exposure of pineal slices (30-180 min) produced further translocation of PKC activity to the membranes and a significant increase of serotonin release. Short-term treatment with pilocarpine and carbachol, stimulated PKC activity of both cytosolic and particulate fractions and the release of pineal serotonin. The pilocarpine effect was blocked by atropine indicating that it was mediated by muscarinic receptors. The present data support that PKC activation correlates with the increase of serotonin release by muscarinic agonist in pineal gland.  相似文献   
999.
1. The oligopeptide AAASFKAKK which contains recognition motifs similar to that found in the surrounding of the site of H1 histone phosphorylated by protein kinase C is unable to compete with H1 histone for the type II and type III isoenzymes, though it is a good substrate for protein kinase C and it is able to compete with a physiological substrate of the enzyme. 2. Among several oligopeptides tested as an alternative substrate a very basic peptide proved to be the most effective inhibitor of H1 histone phosphorylation. This oligopeptide substrate contains basic recognition motifs at both sides of the phosphorylated residue at variance with the sequence of H1 histone in the surrounding of the phosphorylated site.  相似文献   
1000.
1. Upon controlled protein cleavage the catalytic activity of the Ca2(+)-ATPase from sarcoplasmic reticulum is drastically reduced concomitantly with small but significant changes in secondary structure as seen by Fourier transformed infrared (FT-i.r.) spectroscopy, although no loss of protein bound to the membrane is found. 2. FT-i.r. band fitting procedures show a reduction in the beta-sheet and turns content of the protein which is accompanied by an increase in alpha-helix and/or random structure. 3. These changes in the secondary structure of the protein appear to be well correlated to the tryptic digestion pattern and also to changes in the ATP hydrolysis rate of the Ca2(+)-ATPase. 4. It is concluded that these small changes reflect the disruption of key domains of the protein, which lie outside of the membrane matrix, leading to loss of enzymatic activity. 5. FT-i.r. spectroscopy appears to be a very useful technique to study changes in secondary structure of proteins.  相似文献   
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