Ethoxyformylation of histidine residues in equine growth hormone

Reactivity of histidine residues in equine growth hormone to ethoxyformic anhydride was studied. The existence of two kinetically different sets was demonstrated: one of them including only the slow reacting histidine 169 (k = 0.164 min-1) and the other containing fast reacting histidines 19 and 21 (k = 0.892 min-1). A correlation between the decrease in the capacity to compete with 125I-labeled hormone for rat liver binding sites and the degree of ethoxyformylation of the fast group was found. Circular dichroism studies indicated no significant conformational changes in the protein with all three residues modified. These results fully agree with those obtained for bovine growth hormone which is further evidence supporting the vinculation of histidines 19 and/or 21 with the binding site of these hormones to their specific receptors.     

Genetic determinants of glutamine synthetase inDrosophila melanogaster: A gene for glutamine synthetase I resides in the 21B3-6 region

Recombinational and deletion mapping of electrophoretic variants of the glutamine synthetase I isozyme (GSI) in Drosophila melanogaster locates the gene in the 21B region on the second chromosome. We have conducted a genetic analysis of the region extending cytologically from 21A to 21B4-6. Recessive lethal mutations were generated by ethyl methanesulfonate (EMS) and ethyl nitrosourea (ENU) mutagenesis and by hybrid dysgenesis (HD). These lethals fall into seven functional groups, which were partially ordered by complementation with cytologically defined deficiencies of this region generated by hybrid dysgenesis. Two of the EMS- and two of the ENU-induced lethals fulfill biochemical criteria expected for null alleles of the GSI gene.     

The mode of action of Aescin and the release of prostaglandins

The horse-chestnut saponin Aescin, an anti-exudative compound, induces contraction of isolated portal vein of rat and rabbit. This effect appears to be mediated by Prostaglandins of F_α type.The ability of Aescin to stimulate generation and release of Prostaglandins has been demonstrated in isolated lung of the rat. Mass-fragmentographic analysis of the lung effluent indicate that when Aescin is perfused through this organ the release of PGF_2α is increased. The capability of Aescin to generate Prostaglandins is discussed in connection with its anti-exudative activity.     

Phylogeography of Aphanius fasciatus (Osteichthyes: Aphaniidae) in the Mediterranean Sea,with a focus on its conservation in Cyprus

Hydrobiologia - Aphanius fasciatus is a small fish occurring in Mediterranean brackish environments. In Cyprus it is known from three localities separated by long stretches of coast. The genetic...     

Spatial genetic patterns of Octopus vulgaris Mediterranean populations support the hypothesis of a transitional zone across the Siculo-Tunisian Strait

Hydrobiologia - Recent research hypothesised that the Siculo-Tunisian Strait might fit, at least for some species, the picture of a genetic transitional zone instead of a sharp genetic break...     

Cigarette smoke metabolically promotes cancer,via autophagy and premature aging in the host stromal microenvironment

Cigarette smoke has been directly implicated in the disease pathogenesis of a plethora of different human cancer subtypes, including breast cancers. The prevailing view is that cigarette smoke acts as a mutagen and DNA damaging agent in normal epithelial cells, driving tumor initiation. However, its potential negative metabolic effects on the normal stromal microenvironment have been largely ignored. Here, we propose a new mechanism by which carcinogen-rich cigarette smoke may promote cancer growth, by metabolically “fertilizing” the host microenvironment. More specifically, we show that cigarette smoke exposure is indeed sufficient to drive the onset of the cancer-associated fibroblast phenotype via the induction of DNA damage, autophagy and mitophagy in the tumor stroma. In turn, cigarette smoke exposure induces premature aging and mitochondrial dysfunction in stromal fibroblasts, leading to the secretion of high-energy mitochondrial fuels, such as L-lactate and ketone bodies. Hence, cigarette smoke induces catabolism in the local microenvironment, directly fueling oxidative mitochondrial metabolism (OXPHOS) in neighboring epithelial cancer cells, actively promoting anabolic tumor growth. Remarkably, these autophagic-senescent fibroblasts increased breast cancer tumor growth in vivo by up to 4-fold. Importantly, we show that cigarette smoke-induced metabolic reprogramming of the fibroblastic stroma occurs independently of tumor neo-angiogenesis. We discuss the possible implications of our current findings for the prevention of aging-associated human diseases and, especially, common epithelial cancers, as we show that cigarette smoke can systemically accelerate aging in the host microenvironment. Finally, our current findings are consistent with the idea that cigarette smoke induces the “reverse Warburg effect,” thereby fueling “two-compartment tumor metabolism” and oxidative mitochondrial metabolism in epithelial cancer cells.     

Beyond Motor Scheme: A Supramodal Distributed Representation in the Action-Observation Network

The representation of actions within the action-observation network is thought to rely on a distributed functional organization. Furthermore, recent findings indicate that the action-observation network encodes not merely the observed motor act, but rather a representation that is independent from a specific sensory modality or sensory experience. In the present study, we wished to determine to what extent this distributed and ‘more abstract’ representation of action is truly supramodal, i.e. shares a common coding across sensory modalities. To this aim, a pattern recognition approach was employed to analyze neural responses in sighted and congenitally blind subjects during visual and/or auditory presentation of hand-made actions. Multivoxel pattern analyses-based classifiers discriminated action from non-action stimuli across sensory conditions (visual and auditory) and experimental groups (blind and sighted). Moreover, these classifiers labeled as ‘action’ the pattern of neural responses evoked during actual motor execution. Interestingly, discriminative information for the action/non action classification was located in a bilateral, but left-prevalent, network that strongly overlaps with brain regions known to form the action-observation network and the human mirror system. The ability to identify action features with a multivoxel pattern analyses-based classifier in both sighted and blind individuals and independently from the sensory modality conveying the stimuli clearly supports the hypothesis of a supramodal, distributed functional representation of actions, mainly within the action-observation network.     

New echocardiographic techniques in the evaluation of left ventricular function in obesity

Objective:

Obesity has reached global epidemic proportions and is associated with numerous comorbidities, including major cardiovascular (CV) diseases.

Design and Methods:

It has many adverse effects on hemodynamics and CV structure and function: it increases total blood volume and cardiac output, and the cardiac workload is greater. Typically, obese patients have a higher cardiac output but a lower level of total peripheral resistance at any given level of arterial pressure. Most of the increase in cardiac output in obesity is caused by stroke volume, although heart rate typically mildly increases also due to enhanced sympathetic activation.

Results:

Over the last few years, experimental investigations have unraveled some important pathogenetic mechanisms that may underlie a specific form of “obesity cardiomyopathy.” Bariatric surgery represents an effective alternative to treat obesity when nonsurgical weight loss programs (diet + behavior modifications + regular exercise) have failed. A great numbers of questions are still open in the global comprehension of the pathophysiological interactions between obesity and heart.

Conclusion:

Conventional two‐dimensional Doppler echocardiography, integrated by relative new technological ultrasonic approaches, represents the reference technique to study and possibly clarify both the very complex hemodynamic changes induced by obesity and those relative to obesity treatment.     

"Willing to Pay?" Tax Compliance in Britain and Italy: An Experimental Analysis

As shown by the recent crisis, tax evasion poses a significant problem for countries such as Greece, Spain and Italy. While these societies certainly possess weaker fiscal institutions as compared to other EU members, might broader cultural differences between northern and southern Europe also help to explain citizens’ (un)willingness to pay their taxes? To address this question, we conduct laboratory experiments in the UK and Italy, two countries which straddle this North-South divide. Our design allows us to examine citizens’ willingness to contribute to public goods via taxes while holding institutions constant. We report a surprising result: when faced with identical tax institutions, redistribution rules and audit probabilities, Italian participants are significantly more likely to comply than Britons. Overall, our findings cast doubt upon “culturalist” arguments that would attribute cross-country differences in tax compliance to the lack of morality amongst southern European taxpayers.