Determination of heptylphysostigmine in plasma by high-performance liquid chromatography with electrochemical detection

Heptylphysostigmine is a new and very promising cholinergic drug for the treatment of Alzheimer disease. A method has been developed for its determination in plasma with a detection limit of 50 pg/ml. The drug was extracted in n-hexane by a simple one-step procedure, after buffering with sodium bicarbonate. Samples were analysed on a 25 cm x 4.6 mm I.D. silica column (5 microns particle size) using a mixture of acetonitrile, methanol and ammonium nitrate as mobile phase. Since this molecule is quite unstable in plasma, pyridostigmine bromide was added to samples to limit the decomposition. Physostigmine was employed as internal standard. The molecule was electrochemically detected by oxidizing potential (+0.75 V). The method was applied to the analysis of blood samples taken from one healthy volunteer administered this drug. In the same subject the inhibition rate of acetylcholinesterase in plasma and red cells was also measured

Studio dei sistemi di captazione del ferro in germi del genere Vibrio.

Vibrio genus includes bacterial species pathological both for different acquatic organisms and for man, and considering their wide diffusion in acquatic environment, the study of such germs concerns the interactions between them and environment, considered as abiotic elements, i.e. water, and as biotic resources like natural or breeding species, as well as man. The results of interactions germs-environment can be identified in the result of competition for micro- and macro-nourishments, in wich iron element becomes very important. The present research deals with the characterization of isolated Vibrio genus starting from Adriatic sea fish samples, and successive evidence of their iron trasmission systems. 64 bacterial strains have been isolated from seventy fish products samples including cods, mullets, soles, prawns, crabs and clams. The isolated ones have been characterized in a biochemistry way; then 22 have been considered bacteriums belonging to Vibrio genus (n°3 V. cholerae, n°9 V. alginolyticus and n°10 V. parahaemolyticus). These have been tested according to the resistence to an antibiotics range and to the haemolytic power by Kanagawa test made on Wagatsuma agar. Moreover on the examinated bacteriums have been valued the ability to produce siderophores, compounds with low molecular weight, able to bind iron and to represent growth, germination or virulence factors. The production of siderophores has been noticed by bacteriums growth on CAS agar, continuing then in their qualitative valuation by spectrophotometry assay. Moreover, the study of induction of Iron-Regulated Outer Membrane Proteins has been carried out; three different bacterial strains, belonging Vibrio genus, have been cultivated in iron-deficient and iron-enrichment conditions, through M9 Minimal Medium (MM9) with addition of EDDA and ferric chloride, respectively. The outer membrane proteins extracted have been separated in SDS-PAGE and strains grown in iron-deficient media have showed the induction of proteins of 78 kDa for V. alginolyticus and V. parahaemolyticus,77 kDa for V. cholerae. This research represents, relatively to Vibrio genus, a possible starting point in the approach of themes concerning the behaviour of microbic population and the pathogenesis of infections that could negatively affect fish productions and man’s health for fish consumption and for acquarium fish possible zoonosis risks. [...

Pharyngeal pressure value using two continuous positive airway pressure devices

The aim of the study was to measure the difference between the set continuous positive airway pressure (CPAP) value and the pharyngeal pressure reading during CPAP in premature infants with mild respiratory distress syndrome, using two different devices: hood CPAP and the conventional nasal system. The preliminary results suggest that hood CPAP may produce more stable pharyngeal pressure than the conventional nasal devic

Nasal continuous positive airway pressure with heliox in preterm infants with respiratory distress syndrome

To assess the therapeutic effects of breathing a low-density helium and oxygen mixture (heliox, 80% helium and 20% oxygen) in premature infants with respiratory distress syndrome (RDS) treated with nasal continuous positive airway pressure (NCPAP). METHODS: Infants born between 28 and 32 weeks of gestational age with radiologic findings and clinical symptoms of RDS and requiring respiratory support with NCPAP within the first hour of life were included. These infants were randomly assigned to receive either standard medical air (control group) or a 4:1 helium and oxygen mixture (heliox group) during the first 12 hours of enrollment, followed by medical air until NCPAP was no longer needed. RESULTS: From February 2008 to September 2010, 51 newborn infants were randomly assigned to two groups, 24 in the control group and 27 in the heliox group. NCPAP with heliox significantly decreased the risk of mechanical ventilation in comparison with NCPAP with medical air (14.8% vs 45.8%). CONCLUSIONS: Heliox increases the effectiveness of NCPAP in the treatment of RDS in premature infants

HEAT-SHOCK STRESS ON THE DEVELOPING IMMUNE SYSTEM OF SEA BASS

Temperature controls and limits all physiological and behavioural parameters ofectotherms. Within a range of non-lethal temperatures, fishes are generally able tocope with gradual temperature changes that are common in natural systems. However,rapid increases or decreases in ambient temperature, as potentially occur during theaquaculture starvation, may result in sublethal physiological and, or behaviouralresponses. Responses to environmental stress are broadly grouped into threecategories: primary (e.g. neuroendocrine response and corticosteroid–catecholaminerelease), secondary (e.g. metabolic, cellular, haematological, osmoregulatory andimmunological changes) and tertiary (e.g. whole organism physiological andbehavioural stress responses).Apoptosis is a pathway serving to remove unwanted or damaged cells in thecourse of development and differentiation, or in response to various forms of cellulardamage (due for instance to temperature-stress) that did not surpass the thresholdleading to necrotic, accidental, or other forms of cell death. It is conducible to thesecondary response when the process involved lympho-myeloid organs. The commontarget of the diverse stimuli trigger intrinsic or extrinsic apoptosis pathways, bothmediated by a family of cysteine proteases known as caspases. Particularly, themitochondrial compartment is involved in intrisic patways, which via opening of aproteinaceous pore releases molecules into the cytosol. These released molecules thenact as mediators of apoptosis by causing DNA fragmentation and chromatincondensation (AIF, apoptosis inducing factor; endonuclease G), by de-inhibitingcaspases (Smac/DIABLO, second mitochondria-derived activator of caspases/directinhibitor of apoptosis protein-binding protein with low pI; Omi/HtrA2), or by actingas an essential component of a caspase activating platform (cytochrome c). HeatShock Proteins (HSPs) have important anti-apoptotic properties, blocking cell deathand promoting survival, proliferation or differentiation. HSPs are a wide family ofconserved proteins, present in all organisms including fish, and HSP70 kDa familyhas a strong cytoprotective effect, acting as molecular chaperone and mediating therepair or degradation of denaturated proteins.The purpose of this study is to evaluate the sublethal consequences of heatshockon the developing immune system of sea bass (from 50 to 70 days post-hatch)obtained from a commercial hatchery. To this aim we performed an experiment wherefish were exposed for 40 minutes to thermal stress (24 °C) and then sampled after 2hour (T2h), 24 hour (T24h), 10 days (T10gg) and 20 days (T20gg). Control organisms weremaintained at standard temperature condition (19 °C). Samples were analysed byimmunohistochemistry/ELISA to evidence HSP70 and Caspase-3 expression.TUNEL technique was applied to reveal apoptotic cells. Immunohistochemistry wasperformed to evaluate the presence of phagocytes (granulocytes and macrophages)and lymphocytes. RT-PCR analyses were conducted using specific primers for TcRbeta,TcR-gamma and BcR. In the control organisms, immunohistochemistry revealedno particular differences related to organs (thymus, gill, spleen, cephalic kidney) orage, except for a significant increase in apoptosis, HSP70 and caspase-3 activeexpressions in the thymus at 70 days. These results support the role of apoptosis in thelymphoid organ maturation and the function of HSP70 in controlling the process.Compared to control, the stressed sea bass showed a significant increase inapoptosis/caspase-3 (40') followed by an enhanced HSP70 expression (from T2h).[...

Innovative vaccination protocol against vibriosis in Dicentrarchus labrax (L.) juveniles: Improvement of immune parameters and protection to challenge.

The effect of vaccination on immune parameters of European sea bass, Dicentrarchus labrax, is not fully established, as well as surveyed throughout rearing till the commercial size. Furthermore, available information on the possible role of booster treatments is scarce. Sea bass juveniles were vaccinated against Listonella anguillarum using a commercial bivalent formulation administered by immersion (priming: 95 dph; booster: 165 dph) or by immersion (priming: 95 dph; booster: 165 dph) and subsequent i.p. injection (booster: 233 dph). Serum specific IgM and numbers of IgM+ cells in head kidney and spleen evidenced B-cell responses mainly after the immersion booster, accompanied by increased TcR-\u2c7 transcripts and leucocyte respiratory burst. Immune enhancement was confirmed by the protection towards i.p. challenges with a virulent strain. RPS accounted for >70% in fish immersion-boosted and near 100% in fish further boosted i.p. Differently from usual farm practices, this innovative vaccination protocol proved to be highly effective. Booster treatments are therefore strongly recommende