Orexins are neuro-modulatory peptides involved in the control of diverse physiological functions through interaction with two receptors, orexin-1 (OX1R) and orexin-2 (OX2R). Recent evidence in pre-clinical models points toward a putative dichotomic role of the two receptors, with OX2R predominantly involved in the regulation of the sleep/wake cycle and arousal, and the OX1R being more specifically involved in reward processing and motivated behaviour. However, the specific neural substrates underlying these distinct processes in the rat brain remain to be elucidated. Here we used functional magnetic resonance imaging (fMRI) in the rat to map the modulatory effect of selective OXR blockade on the functional response produced by D-amphetamine, a psychostimulant and arousing drug that stimulates orexigenic activity. OXR blockade was produced by GSK1059865 and JNJ1037049, two novel OX1R and OX2R antagonists with unprecedented selectivity at the counter receptor type. Both drugs inhibited the functional response to D-amphetamine albeit with distinct neuroanatomical patterns: GSK1059865 focally modulated functional responses in striatal terminals, whereas JNJ1037049 induced a widespread pattern of attenuation characterised by a prominent cortical involvement. At the same doses tested in the fMRI study, JNJ1037049 exhibited robust hypnotic properties, while GSK1059865 failed to display significant sleep-promoting effects, but significantly reduced drug-seeking behaviour in cocaine-induced conditioned place preference. Collectively, these findings highlight an essential contribution of the OX2R in modulating cortical activity and arousal, an effect that is consistent with the robust hypnotic effect exhibited by JNJ1037049. The subcortical and striatal pattern observed with GSK1059865 represent a possible neurofunctional correlate for the modulatory role of OX1R in controlling reward-processing and goal-oriented behaviours in the rat.

Orexins (OX) and their receptors (OXR) modulate feeding, arousal, stress, and drug abuse. Neural systems that motivate and reinforce drug abuse may also underlie compulsive food seeking and intake. Therefore, the effects of GSK1059865, a dual OX 1 /OX 2 R antagonist were evaluated in a binge eating (BE) model in female rats. BE of highly palatable food (HPF) was evoked by three cycles of food restriction followed by stress, elicited by exposing rats to HPF, but preventing them from having access to it for 15 min. Pharmacokinetic assessments of all compounds were obtained under the same experimental conditions used for the behavioral experiments. Topiramate was used as the reference compound as it selectively blocks BE in rats and humans. Dose-related thresholds for sleep-inducing effects of the OXR antagonists were measured using polysomnography in parallel experiments. SB-649868 and GSK1059865, but not JNJ-10397049, selectively reduced BE for HPF without affecting standard food pellet intake, at doses that did not induce sleep. These results indicate, for the first time, a major role of OX 1 R mechanisms in BE, suggesting that selective antagonism at OX 1 R could represent a novel pharmacological treatment for BE and possibly other eating disorders with a compulsive component.

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Introduction The neuronal mechanism driving Alzheimer's disease (AD) is incompletely understood. Methods Immunohistochemistry, pharmacology, biochemistry, and behavioral testing are employed in two pathological contexts—AD and a transgenic mouse model—to investigate T14, a 14mer peptide, as a key signaling molecule in the neuropathology. Results T14 increases in AD brains as the disease progresses and is conspicuous in 5XFAD mice, where its immunoreactivity corresponds to that seen in AD: neurons immunoreactive for T14 in proximity to T14‐immunoreactive plaques. NBP14 is a cyclized version of T14, which dose‐dependently displaces binding of its linear counterpart to alpha‐7 nicotinic receptors in AD brains. In 5XFAD mice, intranasal NBP14 for 14 weeks decreases brain amyloid and restores novel object recognition to that in wild‐types. Discussion These findings indicate that the T14 system, for which the signaling pathway is described here, contributes to the neuropathological process and that NBP14 warrants consideration for its therapeutic potential.

One hundred forty-three penicillinase-producing Neisseria gonorrhoeae (PPNG) isolates obtained in Argentina from 2008 and 2012 were examined to detect bla TEM-135 genes and to investigate plasmid profiles and multiantigen sequence types. Forty-two PPNG isolates were found to carry TEM-135, and two contained a new TEM derivative characterized as TEM-220. The bla TEM-135 allele was carried by the Toronto/Rio and African plasmids. Molecular epidemiology revealed that two bla TEM-135 isolates were related to previously described isolates from Thailand and China, indicating a common evolutionary origin.A ntibiotic resistance in Neisseria gonorrhoeae is a global public health problem (1). Through the years, N. gonorrhoeae has developed resistance to the first-line antibiotics used for treatment (2). Penicillinase-producing N. gonorrhoeae (PPNG) isolates with plasmid-mediated high-level resistance to penicillin were first reported in 1976 and have spread since then (3). These first PPNG isolates contained TEM-1-type ␤-lactamase plasmids encoded by transposon TnA (Tn2), which are responsible for the transference and dissemination of resistance (4). To date, eight plasmid types have been described in N. gonorrhoeae and named after their epidemiological origin as African, Toronto/Rio, Asian, Nîmes, New Zealand, Johannesburg, and Australian plasmids (5-7). The PPNG isolates carrying a bla TEM-135 gene were found in Thailand, Japan, and China and recently reported in Australia and 15 other countries (8-12). TEM-135 differs from TEM-1 by a single nucleotide substitution at position 539, resulting in a single amino acid substitution, M182T. This substitution is also found in TEM-type extended-spectrum ␤-lactamase (ESBL) but has little effect on enzyme activity, and it has been proposed to stabilize substitutions near the active site, which collaboratively results in the emergence of a stable ESBL (13-15). The first PPNG isolate in Argentina was reported in 1980 and has since been disseminated in our country (16). The prevalence of PPNG isolates has been increasing through the years, with the highest level of 40% in the 1990's. The aim of this study was to detect bla TEM-135 and investigate plasmid types carrying ␤-lactamase in the PPNG strains in 2008 and 2012 in Argentina.We studied 49 and 94 PPNG isolates collected in 2008 and 2012, respectively, from GASSP-AR, which includes 70 laboratories distributed all around the country. The MIC S (g/ml) of penicillin, ciprofloxacin, ceftriaxone, and azithromycin for the isolates were determined by the agar dilution method (17, 18). The N. gonorrhoeae ATCC 49226 and World Health Organization (WHO) reference strains were used for quality control in antimicrobial susceptibility testing (19). Mismatch amplification mutation assay (MAMA) PCR was performed to identify the bla TEM-135 allele, and TEM PCR was used to recognize both the bla TEM-1 and bla . The whole bla TEM , porB, and tbpB genes of all isolates that were MAMA PCR positive were amplified and sequenced to confirm the bla TEM-1...

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Levofloxacin showed comparable in vitro susceptibility to ciprofloxacin among Enterobacteriaceae, Pseudomonas aeruginosa, enterococci, and Staphylococcus aureus, while greater susceptibility was observed in Stenotrophomonas maltophilia and Staphylococcus epidermidis, mainly when oxacillin resistant. The susceptibility of Streptococcus pneumoniae to levofloxacin reached 99%.The recent introduction of levofloxacin, a new fluoroquinolone (FQ), into the Italian clinical scenario led to the need to locally confirm its in vitro activity. Nowadays, only qualitative studies on selected bacterial species have been reported with levofloxacin in Italy (1,3,4,5,6,10,13) but larger studies on clinical isolates are missing. We report here the major findings of a survey carried out on the bacterial species most frequently encountered in the routine work of 24 Italian laboratories distributed Italywide (see Acknowledgments).Each center was requested to collect 194 consecutive, no-copy clinical isolates belonging to a predefined list of bacterial species without any limitation on the ward and/or sample of isolation. All the isolates had to be identified according to the laboratory method used to obtain them. Participants were asked to limit the number of collected Escherichia coli, Staphylococcus aureus, and Staphylococcus epidermidis strains to 30 each per center. The MICs of levofloxacin and ciprofloxacin were determined locally by the Etest (AbBiodisk) method according to the manufacturer's instructions. All the assays were performed on MuellerHinton agar except for Streptococcus pneumoniae and Moraxella catarrhalis, which were tested by using MuellerHinton agar plus 5% sheep blood, and Haemophilus influenzae, which was tested by using Haemophilus test medium (all media were from the same batch). Susceptibility breakpoints were Յ2 g/ml for levofloxacin and Յ1 g/ml for ciprofloxacin according to NCCLS (11). To contain intralaboratory variability, quality controls with E. coli strain ATCC 25922, S. pneumoniae strain ATCC 49619, and H. influenzae strain ATCC 49247 were requested of each center before, during, and after the study's conclusion. The Etest method was selected because of its reliability in testing FQs (9), its ease of use, and its definition of the MIC. Between January and November 2000, case report forms for a total of 4,003 clinical isolates were collected. The quality control results confirmed that the Etest assays were carried out properly during the study, and any center results had to be discharged. As reported by others (9), a slight overestimation (1.6%) of the ciprofloxacin MIC for E. coli ATCC 25922 occurred, but the increase never determined a change in the category. Detailed figures on the isolation wards, samples, and the samples' FQ susceptibilities will be published elsewhere. The isolates and their susceptibilities to levofloxacin and ciprofloxacin are illustrated in Table 1. The Enterobacteriaceae were unhomogeneously susceptible to the study drugs, with a percentage of susceptible strains ranging fr...