Brain Switches Utilitarian Behavior: Does Gender Make the Difference?

Decision often implies a utilitarian choice based on personal gain, even at the expense of damaging others. Despite the social implications of utilitarian behavior, its neurophysiological bases remain largely unknown. To assess how the human brain controls utilitarian behavior, we delivered transcranial direct current stimulation (tDCS) over the ventral prefrontal cortex (VPC) and over the occipital cortex (OC) in 78 healthy subjects. Utilitarian judgment was assessed with the moral judgment task before and after tDCS. At baseline, females provided fewer utilitarian answers than males for personal moral dilemmas (p = .007). In males, VPC-tDCS failed to induce changes and in both genders OC-tDCS left utilitarian judgments unchanged. In females, cathodal VPC-tDCS tended to decrease whereas anodal VPC-tDCS significantly increased utilitarian responses (p = .005). In males and females, reaction times for utilitarian responses significantly decreased after cathodal (p<.001) but not after anodal (p = .735) VPC-tDCS. We conclude that ventral prefrontal tDCS interferes with utilitarian decisions, influencing the evaluation of the advantages and disadvantages of each option in both sexes, but does so more strongly in females. Whereas cathodal tDCS alters the time for utilitarian reasoning in both sexes, anodal stimulation interferes more incisively in women, modifying utilitarian reasoning and the possible consequent actions. The gender-related tDCS-induced changes suggest that the VPC differentially controls utilitarian reasoning in females and in males. The gender-specific functional organization of the brain areas involved in utilitarian behavior could be a correlate of the moral and social behavioral differences between the two sexes.     

Efflux pump genes of the resistance-nodulation-division family in Burkholderia cenocepacia genome

Background  

Burkholderia cenocepacia is recognized as opportunistic pathogen that can cause lung infections in cystic fibrosis patients. A hallmark of B. cenocepacia infections is the inability to eradicate the organism because of multiple intrinsic antibiotic resistance. As Resistance-Nodulation-Division (RND) efflux systems are responsible for much of the intrinsic multidrug resistance in Gram-negative bacteria, this study aims to identify RND genes in the B. cenocepacia genome and start to investigate their involvement into antimicrobial resistance.     

Vitamin E-coated filter decreases levels of free 4-hydroxyl-2-nonenal during haemodialysis sessions

Uraemic subjects undergoing chronic haemodialysis show increased oxidative stress. The use of non-biocompatible filters and reduced antioxidative defences are important sources of reactive oxygen species (ROS) release. The highly oxidative environment accelerates the onset and progression of tissue damage and atherosclerotic cardiovascular disease. The aldehyde 4-hydroxyl-2-nonenal (HNE) is probably the best marker of oxidative stress. In this study, the concentration of plasma HNE was evaluated in eight uremic subjects during two sessions of haemodialysis: the first using a standard biocompatible filter and the second using a filter coated with vitamin E. Baseline plasma levels of HNE were elevated, and dropped during haemodialysis. At the end of the session, however, low levels were maintained only when the vitamin E-modified filter was used. By contrast, a marked increase in HNE was recorded at the end of the session in all subjects who underwent haemodialysis with the conventional filter. This study provides evidence that the vitamin E-coated filter plays a role in counteracting oxidative stress. The chronic use of vitamin E-modified filters in haemodialysed subjects might help to counterbalance oxidative attack and, consequently, contribute to preventing cardiovascular disease.     

Lipoperoxidation in hepatic subcellular compartments of diabetic rats

It is known that an accumulation of lipoperoxidative aldehydes malondialdehyde (MDA) and 4-hydroxynonenal (HNE) takes place in liver mitochondria during aging. The existence and role of an increased extra- and intra-cellular oxidative stress in diabetes, an aging-accelerating disease, is currently under discussion. This report offers evidence that lipoperoxidative aldehydes accumulate in liver microsomes and mitochondria at a higher rate in spontaneously diabetic BB/WOR rats than in control non-diabetic animals (HNE content, diabetes vs. control: microsomes 80.6+/-19.9 vs. 25.75+/-3.6 pmol/mg prot, p = .024; mitochondria 77.4+/-15.4 vs. 26.5+/-3.5 pmol/mg prot, p = .0103). Liver subcellular fractions from diabetic rats, when exposed to the peroxidative stimulus ADP/Fe, developed more lipoperoxidative aldehydes than those from non diabetic rats (HNE amount, diabetes vs. control: microsomes 3.60+/-0.37 vs. 2.33+/-0.22 nmol/mg prot, p = .014; mitochondria 3.62+/-0.26 vs. 2.30+/-0.17 nmol/mg prot, p = .0009). Liver subcellular fractions of diabetic rats developed more fluorescent chromolipids related to HNE-phospholipid adducts, either after in vitro peroxidation (microsomes: p = .0045; mitochondria: p = .0023) or by exposure to exogenous HNE (microsomes: p = .049; mitochondria: p = .0338). This higher susceptibility of diabetic liver membranes to the non-enzymatic attack of HNE may be due to an altered phospholipid composition. Moreover, a decreased activity of the HNE-metabolizing systems can be involved: diabetic liver mitochondria and microsomes were unable to consume exogenous HNE at the same rate as non-diabetic membranes; the difference was already significant after 5' incubation (microsomes p<.001; mitochondria p<.001). These data show an increased oxidative stress inside the hepatocytes of diabetic rats; the impairment of the HNE-metabolizing systems can play a key role in the maintenance and propagation of the damage.     

Effects of ionizing radiation and modified atmosphere packaging on the shelf life of aqua-cultured sea bass (Dicentrarchus labrax)

The major problems concerning marketing and distribution of seafoods are their high perishability due mainly to contamination by spoilage and pathogenic microorganisms. The reduction, destruction or inhibition of microbial contaminants using single or combined treatments might lead to efficient preservation methods. In this research we examined the feasibility of modified atmosphere packaging and irradiation treatments on the extension of the shelf-life of fresh aqua-cultured sea bass Dicentrarchus labrax species. The quality and the freshness of sea bass packaged in modified atmosphere or γ-irradiated were evaluated by assessing their microbiological, sensory and chemical properties. The gas mixture composed by 60:35:5 CO₂/N₂/O₂ resulted as the best inhibitory treatment to extend the shelf life of sea bass. A major MDA containment and microbial decontamination in irradiated samples at 3 kGy were also found in respect to the control samples.     

Cloning a new human gene from chromosome 21q22.3 encoding a glutamic acid-rich protein expressed in heart and skeletal muscle

The identification and functional characterization of genes on chromosome 21 is a necessary step to understand the pathogenesis of the various phenotypic anomalies that affect Down syndrome patients. Using direct cDNA selection we have identified a new gene, SH3BGR, that maps to 21q22.3, proximal to HMG14, and is differentially expressed in heart and skeletal muscle. SH3BGR encodes a novel protein that is characterized by the presence of a proline-rich region containing the consensus sequence for a SH3-binding domain and by an acidic carboxyl-terminal region containing a glutamic acid-rich domain predicted to assume a coiled coil. The presence of two functional domains involved in protein-protein interactions suggests that SH3BGR could be part of a multimeric complex. Its overexpression might alter specific functions of muscular tissue and therefore take part in the pathophysiology of muscular hypotonia in Down syndrome. Received: 12 August 1996 / Revised: 22 October 1996     

Glutathione S-transferase polymorphisms, asthma susceptibility and confounding variables: a meta-analysis

Oxidative stress is one of the main risk factors for asthma development. Glutathione S-transferases play an important role in antioxidant defences and may influence asthma susceptibility. In particular, GSTM1 and GSTT1 positive/null genotypes and the GSTP1*Ile105 Val polymorphism have been analyzed in a number of genetic association studies, with conflicting outcomes. Two previous meta-analyses have attempted to clarify the associations between GST genes and asthma, but these studies have also showed contrasting results. Our aim was to perform a meta-analysis that included independent genetic association studies on GSTM1, GSTP1, and GSTT1, evaluating also the effect of potential confounding variables (i.e. ethnicity, population age, and urbanization). Systematic review and meta-analysis of the effects of GST genes on asthma were conducted. The meta-analyses were performed using a fixed or, where appropriate, random effects model. The meta-analysis of the GSTM1 (n = 35), GSTT1 (n = 31) and GSTP1 (n = 28) studies suggests that no significant associations with asthma susceptibility were observed for GSTM1 and GSTP1 gene polymorphisms, whereas a significant outcome was detected for the GSTT1 positive/null genotype (pooled OR = 1.33, 95 %CI = 1.10–1.60). However, high between-study heterogeneity was identified in all the general analyses (p _{heterogenetity} < 0.05). The stratification analysis seems to explain the heterogeneity only in few cases. This picture is probably due to the interactive process of genetics and environment that characterizes disease pathogenesis. Further studies on interactions of GST genes with the potential oxidative stress sources and with other antioxidant genes are needed to explain the role of GST enzymes in asthma.     

Biodiversity of Lactobacillus plantarum from traditional Italian wines

In this study, 23 samples of traditional wines produced in Southern Italy were subjected to microbiological analyses with the aim to identify and biotype the predominant species of lactic acid bacilli. For this purpose, a multiple approach, consisting in the application of both phenotypic (API 50CHL test) and biomolecular methods (polymerase chain reaction-denaturing gradient gel electrophoresis and 16S rRNA gene sequencing) was used. The results showed that Lactobacillus plantarum was the predominant species, whereas Lb. brevis was detected in lower amount. In detail, out of 80 isolates 58 were ascribable to Lb. plantarum and 22 to Lb. brevis. Randomly amplified polymorphic DNA-polymerase chain reaction was used to highlight intraspecific variability among Lb. plantarum strains. Interestingly, the cluster analysis evidenced a relationship between different biotypes of Lb. plantarum and their origin, in terms of wine variety. Data acquired in this work show the possibility to obtain several malolactic fermentation starter cultures, composed by different Lb. plantarum biotypes, for their proper use in winemaking processes which are distinctive for each wine.     

Site‐specific proteolytic degradation of IgG monoclonal antibodies expressed in tobacco plants

Plants are promising hosts for the production of monoclonal antibodies (mAbs). However, proteolytic degradation of antibodies produced both in stable transgenic plants and using transient expression systems is still a major issue for efficient high‐yield recombinant protein accumulation. In this work, we have performed a detailed study of the degradation profiles of two human IgG1 mAbs produced in plants: an anti‐HIV mAb 2G12 and a tumour‐targeting mAb H10. Even though they use different light chains (κ and λ, respectively), the fragmentation pattern of both antibodies was similar. The majority of Ig fragments result from proteolytic degradation, but there are only a limited number of plant proteolytic cleavage events in the immunoglobulin light and heavy chains. All of the cleavage sites identified were in the proximity of interdomain regions and occurred at each interdomain site, with the exception of the V_L/C_L interface in mAb H10 λ light chain. Cleavage site sequences were analysed, and residue patterns characteristic of proteolytic enzymes substrates were identified. The results of this work help to define common degradation events in plant‐produced mAbs and raise the possibility of predicting antibody degradation patterns ‘a priori’ and designing novel stabilization strategies by site‐specific mutagenesis.     

Nano-patterned SERS substrate: application for protein analysis vs. temperature

We have illustrated the fabrication of nano-structures as a surface enhanced Raman scattering (SERS) substrate using electro-plating and electron-beam lithography techniques to obtain an array of gold nanograin-aggregate structures of diameter ranging between 80 and 100 nm with interstitial gap of 10-30 nm. The nanostructure based SERS substrate permits us to have better control and reproducibility on generation of plasmon polaritons. The calculation shows the possible detection of myoglobin concentration down to attomole. This SERS substrate is used to investigate the structural changes of different proteins; lysozyme, ribonuclease-B, bovin serum albumin and myoglobin in the temperature range between -65 and 90 degrees C. The in-depth analysis even for small conformational changes is performed using 2D Raman correlation analysis and difference Raman analysis in order to gain straightforward understanding of proteins undergoing thermodynamical perturbation.