Repeated exposure to alcoholic beer does not induce long-lasting changes in alcohol self-administration and intake in Sardinian alcohol-preferring and Sardinian non-preferring rats

AIMS: Rats avidly consume non-alcoholic beer, and addition of alcohol to non-alcoholic beer may function as a medium to induce intake of large amounts of alcohol in rats. The present study investigated whether Sardinian alcohol-preferring (sP) and Sardinian non-preferring (sNP) rats, initially exposed to non-alcoholic beer, and subsequently to non-alcoholic beer containing increasing concentrations of alcohol, would develop unusually high alcohol self-administration and drinking behaviours: (i) when alcohol was added to non-alcoholic beer, and (2) once beer was withdrawn and a plain alcohol solution was made available. METHODS: In Experiment 1, rats were exposed to operant, 30-min/day self-administration sessions of non-alcoholic beer with increasing concentrations of alcohol [0, 2.5, 5, 7.5, and 10% (v/v)] for a total of 45 days. After a brief 'beer-fading' phase, the rats were exposed to self-administration sessions of a plain 10% (v/v) alcohol solution. In Experiment 2, the rats were exposed to non-alcoholic beer with increasing concentrations of alcohol [0, 2.5, 5, 7.5, and 10% (v/v)] and water under the 2-bottle choice regimen with unlimited access (24 h/day) for a total of 35 days. After a brief 'beer-fading' phase, the rats were exposed to the choice between a plain 10% (v/v) alcohol solution and water. RESULTS: sP and sNP rats did not differ in self-administration (Experiment 1) and intake (Experiment 2) of non-alcoholic beer. In Experiment 1, as alcohol content increased, the amount of self-administered alcohol increased progressively in sP rats (up to 1-1.2 g/kg) and remained stable in sNP rats (approximately 0.65 g/kg). When the plain 10% alcohol solution was available, the amount of self-administered alcohol in sP rats initially dropped, and tended to increase-up to approximately 0.6 g/kg-on continuing exposure. In sNP rats, their lever-pressing behaviour was rapidly extinguished after beer withdrawal. In Experiment 2, as alcohol content was increased, daily alcohol intake increased progressively in sP rats (up to 8-9 g/kg) and averaged approximately 2.4 g/kg in sNP rats. When the plain alcohol solution was available, daily alcohol intake in sP rats was initially low, reaching control values on continuing exposure; conversely, daily alcohol intake was completely suppressed in sNP rats. CONCLUSIONS: These results suggest that exposure to alcoholic beer resulted in unusually high intakes of alcohol in both sP and sNP rats for as long as non-alcoholic beer was added to alcohol; however, these high levels of alcohol self-administration and intake were not maintained once non-alcoholic beer was withdrawn.     

Changes in patterns of uveitis at a tertiary referral center in Northern Italy: analysis of 990 consecutive cases

Purpose

The role of uveitis, an uncommon ocular disease, is often neglected in research and treatment of autoimmune conditions. The study described the spectrum of uveitis at a referral center in North Italy, and compared that to a previously published series of patients.

Methods

We reviewed all patients with uveitis diagnosed from 2013 to 2015 at the Immunology Eye Unit, Arcispedale S. M. Nuova-IRCCS, Reggio Emilia, Italy. We examined patient characteristics, disease spectrum, and etiologies.

Results

In total, 990 cases of uveitis were identified, who were mostly female (59%) with a median age at presentation of 44 years (interquartile range = 29–57). Anterior uveitis was most frequent (53.5%), followed by panuveitis (22.8%), posterior (16.2%), and intermediate uveitis (5.5%). Anterior herpetic uveitis (15.6%), Fuchs uveitis (9.7%), and HLA-B27 positive anterior uveitis (7.7%) were the most common specific diagnoses. Compared with the previous series, we observed an increased incidence of uveitis, and a different pattern of diagnoses. Rates of herpetic, HLA-B27 positive uveitis, and presumed ocular tuberculosis were higher, but Fuchs uveitis was less frequent.

Conclusions

The pattern of uveitis appears to be changing, very likely due to population-level increases in infectious diseases, to the availability of new diagnostic tests and to the interdisciplinary approach used in patient diagnosis.

     

A different molecular interaction of bradykinin and the synthetic agonist FR190997 with the human B2 receptor: evidence from mutational analysis

Binding affinity at the [3H]-BK binding site and activity as inositol phosphate (IP) production by the peptide bradykinin (BK) and the nonpeptide FR190997 were studied at wild-type or point-mutated human B2 receptors (hB2R) expressed in CHO cells. The effect of the following mutations were analyzed: E47A (TM1), W86A and T89A (TM2), I110A, L114A and S117A (TM3), T158A, M165T and L166F (TM4), T197A and S211A (TM5), F252A, W256A and F259A (TM6), S291A, F292A, Y295A and Y295F (TM7), and the double mutation W256A/Y295F. As the wild-type receptor-binding affinity of FR190997 was 40-fold lower than BK, whereas their agonist potency was comparable, both agonists produced similar maximal effects (Emax). Mutations were evaluated as affecting the affinity and/or efficacy of FR190997 compared with BK. Two mutations were found to impair the agonist affinity of both agonists drastically: W86A and F259A. BK agonist affinity (pEC50) was reduced by 1400- and 150-fold, and that of FR190997 was reduced by 400- and 25-fold, at the W86A and F259A mutant B2 receptors, respectively. Contrary to BK, the affinity of FR190997 was selectively decreased at I110A, Y295A, and Y295F mutants (>103-fold), and a different efficacy was measured at the Y295 mutants, FR190997 being devoid of the capability to trigger IP production at Y295A mutant. L114A, F252A, and W256A selectively impaired the efficacy of FR190997, whereas its binding affinity was not affected. As a consequence, FR190997 behaved as a high-affinity antagonist in blocking the IP production induced by BK. The lack of capability of FR190997 to activate or to bind the double mutant W256A/Y295F suggests that these residues are part of the same binding site, which is also important for receptor activation by the nonpeptide ligand. Overall, by means of mutational analysis, we indicate an hB2R recognition site for the nonpeptide agonist FR190997 (between TM3, 6, and 7), different from that of BK, and show that in the same binding crevice some mutations (L114, W256, and F252) are selectively responsible for the agonist properties of only FR190997.     

Synthesis of 3- or 4-phenyl-1,8-naphthyridine derivatives and evaluation of antimycobacterial and antimicrobial activity

A series of 3- or 4-phenyl-1,8-naphthyridine derivatives variously substituted in the positions 2, 6 and 7 were synthesized and evaluated for in vitro evaluation for their antimycobacterial activity as part of a TAACF TB screening program under the direction of the US National Institute of Health, NIAID division. Several compounds showed an interesting activity when tested at a concentration of 6.25 microg/ml against Mycobacterium tuberculosis H(37)Rv and in particular compounds 2a, 4a,d, 8a,d and 8i, exhibit a % inhibition from 91 to 99. Among these, compounds 2a, 8a and 8d appeared to have a good activity with minimum inhibitory concentrations (MICs) of 6.25 microg/ml. On the basis of the biological results, the most effective substituent in position 2 or 7 seems to be the piperidinyl group. The introduction of a morpholinyl group either in position 2 or 7 of the heterocycle ring caused a decrease in activity. The 1,8-naphthyridine derivatives were also tested in vitro for their antimicrobial activity against Staphylococcus aureus as Gram-positive bacteria and Escherichia coli as Gram-negative bacteria.     

Inflammatory mediators induced by coarse (PM2.5-10) and fine (PM2.5) urban air particles in RAW 264.7 cells

Increased incidence of mortality and morbidity due to cardiopulmonary complications has been found to associate with elevated levels of urban air particles with an aerodynamic diameter <10 micron, PM10 and <2.5 micron, PM2.5. Respirable particles reach the lower respiratory tract where they are phagocytized by alveolar macrophages. Depending on particle composition, exposed macrophages may produce inflammatory mediators. A cascade impactor sampler was used to collect size-fractionated urban air particles. Particulate matter from the city of Rome (Italy) were collected onto stainless steel plates, and recovered using alcohol. The murine monocytic/macrophagic RAW 264.7 cell line was used to compare the ability of PM2.5-10, PM2.5 and carbon black to cause cell injury, such as arachidonic acid (AA) release, tumour necrosis factor alpha (TNF alpha) and interleukin (IL)-6 production. All test particles have been used at the same concentrations 30 and 120 microg/ml. Treatment with PM2.5-10 and PM2.5 induced significant AA release after 5 h of exposure at both concentrations, while carbon black was effective only at the higher concentration. After 5 h of incubation, PM2.5-10 and PM2.5 at 120 microg/ml induced 10 times the amount of TNF alpha than carbon black particles. The urban air particles-stimulated TNF alpha production decreased after 24 h of incubation while carbon black-stimulated TNF alpha was not. IL-6 production was induced by PM2.5 and by PM2.5-10 but not by carbon black. Carbon black was consistently less effective than the urban particles, suggesting that, the contaminants adsorbed on the particles are responsible for the release of inflammatory mediators.     

Interactive role of adenosine and dopamine in the opiate withdrawal syndrome

Adenosine reduces opioid withdrawal symptoms by activating A₁ adenosine receptors, probably by inhibiting excitatory amino acid release. Since blockade of A_2A adenosine receptors seems to enhance dopaminergic striatopallidal transmission, we evaluated the role of the purinergic system in the opiate withdrawal syndrome by using two A₁ receptor agonists [N⁶-cyclohexyladenosine, CHA and 2-chloro-N⁶-cyclopentyladenosine, CCPA], and two A_2A receptor antagonists (SCH 58261 and 8-(3-chlorostyryl)caffeine, CSC).Male adult rats received increasing doses of morphine sulphate suspended in 5 ml/kg of a sustained release preparation (40–100 mg/kg s.c.) daily for 4 days and 20 h after the last administration, the withdrawal syndrome was evoked by naloxone (5 mg/kg i.p.). Animals were observed for 30 min for signs of opiate withdrawal. Other groups of rats were implanted with concentric probes for microdialysis and dopamine levels were measured in the nucleus accumbens. CHA and CCPA (0.05, 0.1 or 0.5 mg/kg i.p.) significantly reduced "wet-dog" shakes, diarrhoea, teeth chattering, jumping and writhing. SCH 58261 and CSC (0.1, 0.5 or 1 mg/kg i.p.), given 10 min before naloxone, also reduced signs of opiate withdrawal. CHA plus SCH 58261 and CCPA plus CSC greatly enhanced the reduction of withdrawal signs observed with CHA and CCPA or CSC and SCH 58261 alone. In vivo microdialysis showed that naloxone significantly decreased DA release; this effect was prevented by pretreatment with systemic SCH 58261 and CSC, but not with CHA and CCPA. Our results demonstrate that A₁ and A_2A adenosine receptors mediate the effect induced by adenosine in opiate withdrawal syndrome and suggest that adenosine A₁ agonists and adenosine A_2A antagonists may be beneficial in the treatment of this syndrome.L. Stella and V. de Novellis share first authorship     

Lithium treatment alters brain concentrations of nerve growth factor,brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor in a rat model of depression

Nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) are proteins involved in neuronal survival and plasticity of dopaminergic, cholinergic and serotonergic neurons in the central nervous system. Since decreased size and impaired function of some neuronal populations may be relevant in depression it has been hypothesized that these molecules may have a functional role in the pathophysiology as well as treatment of depression. Using an animal model of depression, the Flinders Sensitive Line (FSL) rats and their controls, the Flinders Resistant Line (FRL), we investigated the effects of chronic lithium treatment on brain NGF, BDNF and GDNF. Lithium was administered as food supplementation during 6 wk. NGF, BDNF and GDNF measurements were performed by enzyme-linked immunosorbent assay (ELISA). Lithium altered the brain concentrations of neurotrophic factors in the hippocampus, frontal cortex, occipital cortex and striatum. Moreover, the changes were different in the two rat strains. Our data support the notion that neurotrophic factors play a role in depression and in the mechanism of the action of lithium.     

Toll-like receptor signaling mechanisms involved in dendritic cell activation: potential therapeutic control of T cell polarization

Dendritic cells (DCs) represent a bridge between innate and adaptive immunity, being the maturation process dependent on the binding of pathogen-associated molecular patterns (PAMPs) to Toll-Like Receptors (TLRs) expressed on their surface. TLRs associated to adaptor proteins, following binding to PAMPs, are able to skew specific immune responses towards the T helper (h)(1)- or the Th(2)-type according to the antigenic stimulation involved. Of note, other receptors different from TLRs are expressed on DCs which are also able to recognize PAMPs. Among them, one should mention the DC-specific ICAM-3-grabbing nonintegrin, the mannose receptor, Dectin-1 (the major beta-glucan receptor) and NOD2. Finally, the possibility to interfere therapeutically with the TLR-dependent and -independent signaling pathways in DCs is reviewed. According to current literature, DC activation, their antigen uptake capacity and migration can be enhanced with different experimental procedures whose use in humans is still under evaluation. However, just recently a probiotic cocktail VSL3, successfully used in patients with pouchitis, seems to act on DCs, promoting abundant release of Interleukin-10 in the gut. These novel therapeutic strategies based on the modulation of the signaling pathways in DCs seem to be encouraging for the treatment of inflammatory and autoimmune diseases.     

IgE-mediated hypersensitivity to cephalosporins

Like penicillins, cephalosporins may cause IgE-mediated reactions such as urticaria, angioedema, and anaphylactic shock, which occur because of sensitization to determinants shared with penicillins or to unique cephalosporin haptens. In particular, side-chain structures may be responsible for selective sensitization or cross-reactivity. For this reason, individual free cephalosporins are usually employed in skin testing, in addition to the classic penicillin reagents. Cephalosporin skin tests are sensitive in diagnosing immediate hypersensitivity to these betalactams. As far as in vitro tests are concerned, IgE assays for cephalosporins, specifically sepharose-radioimmunoassays, are a potentially useful tool in evaluating immediate reactions and could be used as complementary tests. In selected cases displaying negative results in both skin tests and IgE assays, a graded challenge with the implicated cephalosporin can be performed. Cephalosporin IgE-mediated hypersensitivity may be a transient condition; therefore, allergologic exams should be repeated in patients with negative initial allergologic work-ups, including challenges. Performing allergologic tests with cephalosporins other than the culprit, as well as with penicillin reagents, allows the identification of cross-reactivity with penicillins, selective responses, or cross-reactivity among cephalosporins. In the latter group, cross-reactivity is more frequently related to R1 than to R2 side-chain recognition. In assessing the selectivity of the response, negative results in skin testing with cephalosporins other than the responsible one appear to be a reliable indicator of tolerability.