Analysis of various conditions in order to measure electromyography of isometric contractions in water and on air

The aim of this study was to verify if there are differences in the amplitude of signals from surface electromyography (EMG) during maximal and submaximal voluntary isometric contraction (MVC and 50% MVC, respectively) under different conditions, in our case, water and air, with and without extra protection (water-resistant tape) on the electrode. The isometric force and muscle activation of the MVC and 50% MVC of the biceps brachial muscle of nine healthy trained men were measured simultaneously, performed in water and on air, with and without protection of the EMG electrode. The multivariate analysis of variance with a post hoc Tukey test was applied to detect significant differences between the levels of muscular force. For the amplitude values of the EMG signal, the Wilcoxon signed rank test was applied to compare all experimental conditions in order to detect a significance of p < 0.05. The values of isometric force were not significantly different among conditions (MVC and 50% MVC). The results showed a significant difference among conditions in the water without extra protection compared to the conditions on air with and without extra protection and in water with extra protection. Reduced EMG amplitude was seen in water without extra protection from 37.04% to 55.81% regarding the other conditions. However, no significant difference was seen among conditions in water with extra protection in relation the conditions on air (with and without extra protection). This study suggest that it is necessary to use a water-resistant tape as an extra protection on the electrode when using EMG underwater, to avoid having a significant decrease in the EMG amplitude underwater and not to suffer interference from the water. There was no significant difference among the recordings of EMG with and without the use of protection on air; therefore, the protection does not influence the recording of EMG amplitude and isometric force on air.     

Zika virus infection drives epigenetic modulation of immunity by the histone acetyltransferase CBP of Aedes aegypti

Epigenetic mechanisms are responsible for a wide range of biological phenomena in insects, controlling embryonic development, growth, aging and nutrition. Despite this, the role of epigenetics in shaping insect-pathogen interactions has received little attention. Gene expression in eukaryotes is regulated by histone acetylation/deacetylation, an epigenetic process mediated by histone acetyltransferases (HATs) and histone deacetylases (HDACs). In this study, we explored the role of the Aedes aegypti histone acetyltransferase CBP (AaCBP) after infection with Zika virus (ZIKV), focusing on the two main immune tissues, the midgut and fat body. We showed that the expression and activity of AaCBP could be positively modulated by blood meal and ZIKV infection. Nevertheless, Zika-infected mosquitoes that were silenced for AaCBP revealed a significant reduction in the acetylation of H3K27 (CBP target marker), followed by downmodulation of the expression of immune genes, higher titers of ZIKV and lower survival rates. Importantly, in Zika-infected mosquitoes that were treated with sodium butyrate, a histone deacetylase inhibitor, their capacity to fight virus infection was rescued. Our data point to a direct correlation among histone hyperacetylation by AaCBP, upregulation of antimicrobial peptide genes and increased survival of Zika-infected-A. aegypti.     

Assessment of a DNA vaccine encoding an anchored-glycosylphosphatidylinositol tegumental antigen complexed to protamine sulphate on immunoprotection against murine schistosomiasis

Protamine sulphate/DNA complexes have been shown to protect DNA from DNase digestion in a lipid system for gene transfer. A DNA-based vaccine complexed to protamine sulphate was used to induce an immune response against Schistosoma mansoni anchored-glycosylphosphatidylinositol tegumental antigen in BALB/c mice. The protection elicited ranged from 33 to 44%. The spectrum of the elicited immune response induced by the vaccine formulation without protamine was characterized by a high level of IgG (IgG1> IgG2a). Protamine sulphate added to the DNA vaccine formulation retained the green fluorescent protein encoding-plasmid longer in muscle and spleen. The experiments in vivo showed that under protamine sulphate effect, the scope of protection remained unchanged, but a modulation in antibody production (IgG1= IgG2a) was observed.     

Population genetics of Glutathione peroxidase (GPX1) in Central Portugal

The isoenzymes of red cell glutathione peroxidase (GPX1) was investigated in the population of Central Portugal. A variant of GPX1 with mobility consistent with GPX1^*2 was detected with a frequency of: GPX1^*2=0,005 (N=221).     

Effect of cholesterol or cholesteryl conjugates on the cryosurvival of bull sperm

Different cholesterol conjugates-loaded-cyclodextrin was added to bull sperm to improve sperm quality after freezing. Ejaculates from four bulls were diluted to 120 million cells/ml in Tris (T) diluent and then sub-divided into 10 treatments as follow: no additive (control); 1.5 mg CLC (positive control); 0.75 mg or 1.5 mg of cyclodextrin pre-loaded with cholesterol conjugated to heptanoate, palmitate, pelargonate or stearate, and incubated for 15 min at 22 °C. The samples were then diluted 1:1 with 20% egg yolk (EY) in T diluent and cooled to 5 °C over a 2 h. Upon reaching 5 °C, the samples were diluted 1:1 with T diluent containing 10% EY + 16% glycerol, and allowed to equilibrate for 15 min, and packaged into 0.5 ml straws and frozen in static liquid nitrogen vapor for 20 min before being plunged into liquid nitrogen for storage. Straws were thawed and the sperm motility, viability and number sperm binding to perivitelline membrane were determined. The ability of bull sperm to bind to the oocyte membranes was conducted using the chicken egg perivitelline membrane (CEPM) as described by Barbato et al. [G.F. Barbato, P.G. Cramer, R.H. Hammerstedt, A practical in vitro sperm-egg binding assay that detects subfertile males. Biol. Reprod. 58 (1998) 686-699] and modified by Amorim et al. [E. Amorim, J.K. Graham, B. Spizziri, M. Meyers, L. Amorim, C. Torres, The effect of adding cholesteryl-heptanoate, -palmitate, -pelargonate, or -stearate loaded cyclodextrin on bull sperm cryosurvival, in: Proceeding 40th Annual Meeting of the Society for the Study of Reproduction (SSR), July, San Antonio, TX, EUA, 2007], where these authors did not observe difference between bovine zona pellucide and CEPM. Higher percentages of motile and viable sperm were maintained after thawing from bull sperm treated with CLC and pelargonate compared to all other treatments (P < 0.05). Control samples and sperm treated with heptanoate, palmitate, or stearate loaded cyclodextrin exhibited similar motility percentages and viable sperm after freezing (P > 0.05). The percentage of motile sperm and number sperm binding to chicken egg perivitelline membrane was higher for CLC and pelargonate compared to control (P < 0.05). Therefore, adding either cholesterol or pelargonate to bull sperm membranes improved cell cryosurvival, whereas treatments with cyclodextrins pre-loaded with other cholesterol-like molecules did not.     

Metabolism of the mesoionic compound (MI‐D) by mouse liver microsome,detection of its metabolite In Vivo,and acute toxicity in mice

The mesoionic derivative 4‐phenyl‐5‐[4‐nitrocinnamoyl]‐1,3,4‐thiadiazolyl‐2‐phenylamine chloride (MI‐D) has antitumoral and anti‐inflammatory effects. In this study, we present aspects of its metabolism and toxicity in mice. MI‐D was metabolized in vitro by liver microsome, generating a main product with a much shorter retention time than MI‐D in high‐performance liquid chromatography (HPLC) analysis but with a spectrum similar to that of the original molecule. Mass spectrometry with electrospray ionization in positive mode analysis of the purified compound by HPLC indicated that the product of metabolism has four additional hydroxyl groups (m/z = 465) compared with MI‐D (m/z = 401). The HPLC analyses of plasma and urine samples from mice treated with MI‐D showed the presence of the metabolite product. The kinetic parameters K_m (19.5 ± 4.5 μM) and V_max [1.5 ± 0.4 units of fluorescence/(100 μg of microsomal protein/mL/s)] were estimated, confirming the metabolism of MI‐D and indicating that the reaction follows Michaelis‐Menten kinetics. Acute toxicity was established on the basis of an estimation of mean lethal dose (LD‐50; 181.2 mg/kg) and histopathological analysis of animals that survived the LD‐50 test. Abdominal adhesions, inflammatory foci, and formation of granulomas were observed. Altogether, the results contribute to the advancement of research in support of MI‐D as a future chemotherapeutic drug. © 2009 Wiley Periodicals, Inc. J Biochem Mol Toxicol 23:394–405, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jbt.20303     

Phylogeographic analysis of paternal lineages in NE Portuguese Jewish communities

The establishment of Jewish communities in the territory of contemporary Portugal is archaeologically documented since the 3rd century CE, but their settlement in Trás‐os‐Montes (NE Portugal) has not been proved before the 12th century. The Decree of Expulsion followed by the establishment of the Inquisition, both around the beginning of the 16th century, accounted for a significant exodus, as well as the establishment of crypto‐Jewish communities. Previous Y chromosome studies have shown that different Jewish communities share a common origin in the Near East, although they can be quite heterogeneous as a consequence of genetic drift and different levels of admixture with their respective host populations. To characterize the genetic composition of the Portuguese Jewish communities from Trás‐os‐Montes, we have examined 57 unrelated Jewish males, with a high‐resolution Y‐chromosome typing strategy, comprising 16 STRs and 23 SNPs. A high lineage diversity was found, at both haplotype and haplogroup levels (98.74 and 82.83%, respectively), demonstrating the absence of either strong drift or founder effects. A deeper and more detailed investigation is required to clarify how these communities avoided the expected inbreeding caused by over four centuries of religious repression. Concerning haplogroup lineages, we detected some admixture with the Western European non‐Jewish populations (R1b1b2‐M269, ～28%), along with a strong ancestral component reflecting their origin in the Middle East [J1(xJ1a‐M267), ～12%; J2‐M172, ～25%; T‐M70, ～16%] and in consequence Trás‐os‐Montes Jews were found to be more closely related with other Jewish groups, rather than with the Portuguese non‐Jewish population. Am J Phys Anthropol 2010. © 2009 Wiley‐Liss, Inc.