Dynamics of heparin-binding proteins on boar sperm

The presence, topology and dynamics of heparin-binding proteins (HBP) on boar sperm were evaluated. HBP distribution was analyzed by subcellular parting, using biotinylated heparin followed by colorimetric detection. HBP were detected as peripherical and integral periacrosomal membrane proteins. Indirect fluorescence microscopy of sperm incubated with biotinylated heparin was used to evidence heparin binding on sperm at different physiological stages. Two different fluorescent patterns (A and B) were found, which probably correspond to non-capacitated and capacitated sperm as assessed by the ability to undergo acrosome reaction with calcium ionophore A23187 and by the increase of p32 phosphorylated protein. In A pattern, corresponding to untreated sperm, fluorescence located mostly on the post-acrosomal region; in B pattern, corresponding to incubated sperm, on the acrosomal region. Upon incubation under capacitating conditions (TALP), sperm having the B pattern was augmented compared with non-incubated sperm (p < 0.001). Differences in the HBP patterns (p < 0.0001) were observed in sperm incubated under non-capacitating conditions in relation to sperm incubated in TALP, indicating that the modification of HBP patterns is probably related to capacitation. No difference was observed when untreated sperm were permeabilized prior to staining, suggesting that HBP are present on the sperm surface. The effect of heparin on capacitation dependent protein tyrosine phosphorylation was also analyzed, finding a decrease in p32 phosphorylation in the presence of heparin. This suggests that the capacitation enhancement mediated by this glycosaminoglycan involves an alternative intracellular pathway. The finding that heparin binds to sperm differently according to its physiological state, is a new evidence of the remodelling of sperm membrane surface upon capacitation and may provide a useful and relatively simple method to evaluate in vitro modification of boar sperm physiological state.     

Effect of photodynamic therapy on the skin using the ultrashort laser ablation

Photodynamic Therapy (PDT) with 5‐aminolevulinic acid (ALA) is known to be limited for applications in tumours of large volume mainly due to the limited penetration of topical photosensitization. The results show that micro‐holes created using a femtosecond laser before PDT significantly increased the depth of PDT effect in the healthy tissue. The combination of ultrashort laser ablation technique with PDT showed an important scientific breakthrough related to transportation and delivery of drugs into the deeper regions of the tissue. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Europium complexes of 1,10-phenanthrolines: Their inclusion in liposomes and cytotoxicity

Cytotoxic effect of a series of 1,10-phenanthroline coordination complexes with europium tris-β-diketonate (EuCs) against HBL-100 human breast carcinoma cells was determined. Cytotoxicity of liposomal formulation of V12, the most active EuC, was also studied. In vivo testing of this formulation on a started ASF-LL lethal murine model of T-cell leukemic lymphoma showed that the inclusion of V12 in liposomes did not result in enhancement of its antitumor activity in a local mode of administration.     

Leaf Litter Decomposition and Monodominance in the Peltogyne Forest of Marací Island, Brazil1

The forest type dominated by Peltogyne gracilipes (Caesalpiniaceae) on the riverine Marací Island is the least speciesrich of any recorded for Brazilian Amazonia. Because the forest has high soil and foliar Mg concentrations, and Mg is known to be toxic to plant growth at high concentrations, this study tested the hypothesis that dominance by Peltogyne is related to Mg leaf litter amounts and decomposition. We predicted that decomposition of Peltogyne leaves would differ from that of other species, and that their decomposition would result in a pulse of Mg release. Three plots (50 × 50 m) were established in each of three forest types: Peltogyne‐rich forest (PRF; dominated by P. gracilipes),Peltogyne‐poor forest (PPF), and forest without Peltogyne (FWP). Three leaf litter decomposition experiments tested if decomposition of mixed leaf litter in coarse‐ mesh (CM) litterbags differed among forests (experiment 1); whether or not decomposition and nutrient release of Ecclinusa guianensis, Lueheopsis duckeana, and Peltogyne in CM litterbags differed among forests and species (experiment 2); and using fine‐mesh (FM) litterbags, investigated the differences in the influence of fauna! activity on Ecclinusa and Peltogyne decomposition (experiment 3). Decomposition was independent of the presence and dominance of Peltogyne, since decomposition rates in both PRF and FWP were in general lower than in PPF. These differences appeared to be related to fauna] activity. The decomposition of Peltogyne leaves was lower than that of the other species tested and was more affected by microbial and physical action. It is possible that the monodominance of Peltogyne is related to its deciduousness and faster decomposition in the dry season, which coincides with a large leaf fall. Magnesium was lost quickly from the Peltogyne leaves and the resultant pulses of Mg into the soil during the heavy rains at the beginning of the wet season may be deleterious for other species that are not adapted to high solution Mg concentrations. Results obtained were consistent with the hypothesis that Peltogyne dominance is related to the pattern of its leaf decomposition and the seasonal pulses of toxic Mg.     

BACE1 regulates voltage-gated sodium channels and neuronal activity

BACE1 activity is significantly increased in the brains of Alzheimer's disease patients, potentially contributing to neurodegeneration. The voltage-gated sodium channel (Na(v)1) beta2-subunit (beta2), a type I membrane protein that covalently binds to Na(v)1 alpha-subunits, is a substrate for BACE1 and gamma-secretase. Here, we find that BACE1-gamma-secretase cleavages release the intracellular domain of beta2, which increases mRNA and protein levels of the pore-forming Na(v)1.1 alpha-subunit in neuroblastoma cells. Similarly, endogenous beta2 processing and Na(v)1.1 protein levels are elevated in brains of BACE1-transgenic mice and Alzheimer's disease patients with high BACE1 levels. However, Na(v)1.1 is retained inside the cells and cell surface expression of the Na(v)1 alpha-subunits and sodium current densities are markedly reduced in both neuroblastoma cells and adult hippocampal neurons from BACE1-transgenic mice. BACE1, by cleaving beta2, thus regulates Na(v)1 alpha-subunit levels and controls cell-surface sodium current densities. BACE1 inhibitors may normalize membrane excitability in Alzheimer's disease patients with elevated BACE1 activity.     

Plant regeneration from stem and petiole-derived callus ofHumulus lupulus L. (hop) clone Bragança and var. Brewer’s Gold

Summary Plant regeneration was achieved from both a spontaneous clone (Bragan?a) and Brewer's Gold variety ofHumulus lupulus. The results obtained for these two different genotypes were compared. The organogenic ability of petiole and stem segments was tested on three different basal media supplemented with 0.025 mg (0.14 μM) indole-3-acetic acid/L and 2 mg (8.87 μM) 6-benzylaminopurine (N⁶-benzyladenine)/L. These conditions induced rather heterogeneous responses, which depended mainly on the explant source and the genotype. Because of the high organogenic competence revealed by the spontaneous clone on modified Murashige and Skoog medium, several hormones in different combinations were tested to optimize conditions for adventitious shoot regeneration in this clone. The best relation between the average shoot number/callus and the regeneration rate was achieved with 0.025 mg (0.14 μM) indole-3-acetic acid/L and 2 mg (8.87 μM) 6-benzylaminopurine/L or with 0.02 mg (0.11 μM) indole-3-acetic acid/L and 1.5 mg (6.97 μM) kinetin/L, which enabled 72 and 59% of regeneration, respectively. The regenerated plantlets could be acclimatized with 90% success.     

Red-green color vision impairment in Duchenne muscular dystrophy

The present study evaluated the color vision of 44 patients with Duchenne muscular dystrophy (DMD) (mean age 14.8 years; SD 4.9) who were submitted to a battery of four different color tests: Cambridge Colour Test (CCT), Neitz Anomaloscope, Ishihara, and American Optical Hardy-Rand-Rittler (AO H-R-R). Patients were divided into two groups according to the region of deletion in the dystrophin gene: upstream of exon 30 (n=12) and downstream of exon 30 (n=32). The control group was composed of 70 age-matched healthy male subjects with no ophthalmological complaints. Of the patients with DMD, 47% (21/44) had a red-green color vision defect in the CCT, confirmed by the Neitz Anomaloscope with statistical agreement (P<.001). The Ishihara and the AO H-R-R had a lower capacity to detect color defects--5% and 7%, respectively, with no statistical similarity between the results of these two tests nor between CCT and Anomaloscope results (P>.05). Of the patients with deletion downstream of exon 30, 66% had a red-green color defect. No color defect was found in the patients with deletion upstream of exon 30. A negative correlation between the color thresholds and age was found for the controls and patients with DMD, suggesting a nonprogressive color defect. The percentage (66%) of patients with a red-green defect was significantly higher than the expected <10% for the normal male population (P<.001). In contrast, patients with DMD with deletion upstream of exon 30 had normal color vision. This color defect might be partially explained by a retina impairment related to dystrophin isoform Dp260.