Bilateral impairments of shoulder abduction in chronic hemiparesis: Electromyographic patterns and isokinetic muscle performance

ObjectiveTo analyze electromyographic (EMG) patterns and isokinetic muscle performance of shoulder abduction movement in individuals who sustained a cerebrovascular accident (CVA).DesignTwenty-two individuals who sustained a CVA and 22 healthy subjects volunteered for EMG activity and isokinetic shoulder abduction assessments. EMG onset time, root mean square (RMS) for upper trapezius and deltoid muscles, as well as the isokinetic variables of peak torque, total work, average power and acceleration time were compared between limbs and groups.ResultsThe paretic side showed a different onset activation pattern in shoulder abduction, along with a lower RMS for both muscles (21.8 ± 13.4% of the maximal voluntary isometric contraction (MVIC) for the deltoid and 25.9 ± 15.3% MVIC for the upper trapezius, about 50% lower than the control group). The non-paretic side showed a delay in both muscles activation and a lower RMS for the deltoid (32.2 ± 13.7% MVIC, about 25% lower than the control group). Both sides of the group of individuals who sustained a CVA presented a significantly lower isokinetic performance compared to the control group (paretic side ～60% lower; non-paretic side ～35% lower).ConclusionsShoulder abduction muscle performance is impaired in both paretic and non-paretic limbs of individuals who sustained a CVA.     

Selecting Species for Passive and Active Riparian Restoration in Southern Mexico

In revegetation projects, distinguishing species that can be passively restored by natural regeneration from those requiring active restoration is not a trivial decision. We quantified tree species dominance (measured by an importance value index, IVI_i) and used abundance–size correlations to select those species suitable for passive and/or active restoration of disturbed riparian vegetation in the Lacandonia region, Southern Mexico. We sampled riparian vegetation in a 50 × 10–m transect in each of six reference (RE) and five disturbed (DE) riparian ecosystems. Those species representing more than 50% of total IVI in each ecosystem were selected, and Spearman rank correlation between abundance and diameter classes was calculated. For eight species, it was determined that passive restoration could be sufficient for their establishment. Another eight species could be transplanted by means of active restoration. Five species regenerate well in only one ecosystem type, suggesting that both restoration strategies could be used depending on the degree of degradation. Finally, two species were determined to not be suitable for restoration in the RE (based on the above selection criteria) and were not selected during this initial stage of our restoration project. The high number of tree species found in the RE suggests that the species pool for ecological restoration is large. However, sampling in both ecosystem types helped us reduce the number of species that requires active restoration. Restoration objectives must guide the selection of which methods to implement; in different conditions, other criteria such as dispersal syndrome or social value could be considered in the species selection.     

The effects of hydrocarbon pollution from a two‐stroke outboard engine on the feeding behaviour of Lythrypnus dalli (Perciformes: Gobidae)

Feeding behaviour (time of attack on flake fish food) in Lythrypnus dalli was measured under pollution concentrations of 2.1 and 4.01mgl^?1 total extractable material produced by a two‐stroke outboard engine. The variance of the times increased in pollution versus control treatments for both concentrations. No significant difference was found between the mean times of the control and 2.1 mgl^?1 pollution treatments. A significant difference was found between the mean times of the control and pollution treatments for two different tests at 4.01 mgl^?1. The combination of the increase in mean time of food attack and the increase of variance indicates that pollution concentrations lower than LD50 levels change feeding behaviour, and thus may indirectly effect the survival of the organism.     

Vinpocetine attenuates the metabolic dysfunction induced by amyloid β-peptides in PC12 cells

The cytoprotective effect of vinpocetine [14-ethoxycarbonyl-(3α,16α-ethyl)-14,15-eburnamine] was investigated on PC12 cells treated with the amyloid β-peptides (Aβ) for 24 hours. Vinpocetine was shown to protect cells from the inhibition in redox status induced by exposure to Aβ_25–35 and Aβ_1–40, the maximal protection being achieved at a vinpocetine concentration of 40 μM. At this concentration, vinpocetine blocked the inhibition of the mitochondrial respiratory chain complexes II–III and IV and completely abolished the depletion of pyruvate levels induced by toxic concentrations of Aβ peptides. Furthermore, the accumulation of ROS in cells exposed to Aβ_25–35 and Aβ_1–40 evaluated using the fluorescent probe 2′,7′-dichlorofluorescin (DCF), was reduced in the presence of 40 μM vinpocetine. Taken together, the data presented herein demonstrate that vinpocetine protects cells from Aβ toxicity, preventing the generation of oxidative stress due to the excessive accumulation of ROS. This study suggests that vinpocetine can exert neuroprotective properties which might be of importance and contribute to its clinical efficacy in the treatment of Alzheimer's disease or other neurodegenerative disorders in which oxidative stress is involved.     

Linkage Mapping and Molecular Diversity at the Flower Sex Locus in Wild and Cultivated Grapevine Reveal a Prominent SSR Haplotype in Hermaphrodite Plants

Cultivars used for wine and table grape have self-fertile hermaphrodite flowers whereas wild European vines and American and Asian species are dioecious, having either male or female flowers. Consistent with previous studies, the flower sex trait was mapped as a single major locus on chromosome 2 based on a pure Vitis vinifera population segregating for hermaphrodite and female progeny, and a hybrid population producing all three flower sex types. The sex locus was placed between the same SSR and SNP markers on both genetic maps, although abnormal segregation hampered to fine map the genomic region. From a total of 55 possible haplotypes inferred for three SSR markers around the sex locus, in a population of 132 V. sylvestris accessions and 171 V. vinifera cultivars, one of them accounted for 66 % of the hermaphrodite individuals and may be the result of domestication. Specific size variants of the VVIB23 microsatellite sequence within the 3′-UTR of a putative YABBY1 gene were found to be statistically significantly associated with the sex alleles M, H and f; these markers can provide assistance in defining the status of wild grapevine germplasm.     

Synthesis of Duplex DNA Containing a Spin Labeled Analog of 2′ Deoxycytidine

Abstract

We report the chemical synthesis of phosphoramidite 8, containing a spin labeled analog of deoxycytidine, C?, and its incorporation into synthetic DNA. The EPR characteristics of the resulting DNAs indicated that the motion of the spin label was well-correlated with the uniform modes of the macromolecule, but that correlation of the spin label with internal motion was less effective than that achieved using a spin labeled quinolone, Q.     

Pharmacological and nutritional agents promoting browning of white adipose tissue

The role of brown adipose tissue in the regulation of energy balance and maintenance of body weight is well known in rodents. Recently, interest in this tissue has re-emerged due to the realization of active brown-like adipose tissue in adult humans and inducible brown-like adipocytes in white adipose tissue depots in response to appropriate stimuli (“browning process”). Brown-like adipocytes that appear in white fat depots have been called “brite” (from brown-in-white) or “beige” adipocytes and have characteristics similar to brown adipocytes, in particular the capacity for uncoupled respiration. There is controversy as to the origin of these brite/beige adipocytes, but regardless of this, induction of the browning of white fat represents an attractive potential strategy for the management and treatment of obesity and related complications. Here, the different physiological, pharmacological and dietary determinants that have been linked to white-to-brown fat remodeling and the molecular mechanisms involved are reviewed in detail. In the light of available data, interesting therapeutic perspectives can be expected from the use of specific drugs or food compounds able to induce a program of brown fat differentiation including uncoupling protein 1 expression and enhancing oxidative metabolism in white adipose cells. However, additional research is needed, mainly focused on the physiological relevance of browning and its dietary control, where the use of ferrets and other non-rodent animal models with a more similar adipose tissue organization and metabolism to humans could be of much help. This article is part of a Special Issue entitled Brown and White Fat: From Signaling to Disease.     

Analysis of castor bean ribosome-inactivating proteins and their gene expression during seed development

Ribosome-inactivating proteins (RIPs) are enzymes that inhibit protein synthesis after depurination of a specific adenine in rRNA. The RIP family members are classified as type I RIPs that contain an RNA-N-glycosidase domain and type II RIPs that contain a lectin domain (B chain) in addition to the glycosidase domain (A chain). In this work, we identified 30 new plant RIPs and characterized 18 Ricinus communis RIPs. Phylogenetic and functional divergence analyses indicated that the emergence of type I and II RIPs probably occurred before the monocot/eudicot split. We also report the expression profiles of 18 castor bean genes, including those for ricin and agglutinin, in five seed stages as assessed by quantitative PCR. Ricin and agglutinin were the most expressed RIPs in developing seeds although eight other RIPs were also expressed. All of the RIP genes were most highly expressed in the stages in which the endosperm was fully expanded. Although the reason for the large expansion of RIP genes in castor beans remains to be established, the differential expression patterns of the type I and type II members reinforce the existence of biological functions other than defense against predators and herbivory.