Sero-surveillance of emerging viral diseases in camels and cattle in Nouakchott, Mauritania: an abattoir study.

This study reports the monitoring of several emerging viral pathogens in Mauritania, which was carried out by the analysis of bovine and camel samples taken at the slaughterhouse of Nouakchott. Blood and serum were collected by random sampling from 159 camels and 118 cattle in March 2013 at the large animals abattoir in Nouakchott. Serological tests for Rift Valley Fever (RVF), Peste des Petits Ruminants (PPR), West Nile disease (WND), epizootic haemorrhagic disease (EHD) and African horse sickness (AHS) were carried out using commercial ELISA kits. The samples, which resulted positives for PPR, WND and AHS, were tested with the confirmatory virus neutralization test (VNT). According to ELISA results, serological prevalence of RVF was 45% (95% CI 52.3-37.7) in camels and 16% (95% CI 22.6-9.4) in cattle. The difference between the observed prevalences in camels and in cattle was significant (p value ≤ 0.01). PPR was absent in camels and had 12% prevalence (95% CI, 17.86-6.14) in cattle. Furthermore, camels showed 92% (95% CI, 96.1-87.9) prevalence of WNV, 73% (95% CI, 82.3-63.64) of EHD and 3% (95% CI, 5.6-0.4) of AHS. This data are of relevance since provided useful feedbacks on the circulation of the pathogens in field. Moreover, this survey provided new information on the susceptibility of camels to several emerging pathogens and on the possible use of this species as sentinel animal.

Experimental infection of rock pigeons (Columba livia) with three West Nile virus lineage 1 strains isolated in Italy between 2009 and 2012.

West Nile virus (WNV) circulation dynamics in the context of the urban environment is not yet elucidated. In this perspective, three groups of eight rock pigeons (Columbia livia) were inoculated with three WNV lineage 1 strains isolated in Italy between 2009 and 2012. The pigeons did not develop any clinical signs consistent with WNV acute infection. All animals seroconverted and shed virus up to 15 days post-infection by the oral or cloacal routes. In all infected groups viraemia lasted for 4 days post-infection. No WNV-specific gross or histological lesions were found in infected birds compared to control birds and immunohistochemistry remained constantly negative from all tissues. The reservoir competence index was also assessed and it ranged between 0·11 and 0·14. This study demonstrates that pigeons are competent reservoir hosts for Italian WNV lineage 1 circulating strains thus potentially posing a risk to the public health system.

Bluetongue virus in Lebanon.

Since 2000, several incursions of bluetongue virus (BTV) occurred in the Mediterranean Basin involving European and surrounding Countries. The Middle East represents one of the most important gateways for the access of BTV in Europe. Limited data on the BTV situation in this area are available. In this perspective, an epidemiological survey on the presence of BTV in Lebanon was conducted. Of the 181 serum samples tested, 97 (mean = 53.6%; 95% CI: 46.3-60.7) resulted positive when tested for the presence of BTV antibodies by c-ELISA, of these 42 (mean = 42%; 95% CI: 32.8-51.8) serum samples were from sheep and 55 (mean = 67.9%; 95% CI: 57.1-77.1) serum samples were from goats. Fourteen blood samples (14/110; mean = 12.7%; 95% CI: 7.8-20.3), 6 (6/66; mean = 9.1%; 95% CI: 4.4-18.5) from sheep and 8 (8/44; mean = 18.2%; 95% CI: 9.6-32.0) from goats, were positive by qRT-PCR. The results with serum-neutralization assay and typing performed by RT-PCR confirmed that six BTV serotypes are currently circulating in Lebanon, and these serotypes are as follows: 1, 4, 6, 8, 16 and 24. This study is the first report that confirms the presence and circulation of BTV in Lebanon.

2-Phenylethynyl-butyltellurium enhances learning and memory impaired by scopolamine in mice.

Taking into account the memory-enhancing properties of 2-phenylethynyl-butyltellurium (PEBT) and the constant search for drugs that improve cognitive performance, the present study was designed to investigate the effect of PEBT on cognitive impairment induced by scopolamine in mice. PEBT (10 mg/kg, gavage) was administered to mice 1 h before the probe trial in the Morris water maze task. Memory impairment was induced by scopolamine (1 mg/kg, intraperitoneally) 30 min before the probe trial. PEBT significantly ameliorated the scopolamine-induced impairment of long-term memory, as indicated by a decrease in escape latency and an increase in the number of crossings of the platform location when compared with the amnesic mice. To evaluate the effect of PEBT on different phases of memory (acquisition, consolidation, and retrieval) impaired by scopolamine, the step-down inhibitory avoidance task was used. Scopolamine was administered 30 min before training (acquisition), test (retrieval), or immediately after training (consolidation). PEBT, administered 30 min before scopolamine, increased step-down latency in memory-impaired mice, improving the consolidation and retrieval stages, but not acquisition. No significant alterations in locomotor or exploratory behaviors were found in animals treated with PEBT and/or scopolamine. PEBT improved memory deficits during consolidation and retrieval induced by scopolamine.

2,2'-dipyridyl diselenide is a better antioxidant than other disubstituted diaryl diselenides.

The aim of this study was to investigate the in vitro antioxidant activity of 2,2'-dipyridyl diselenide (e) by comparing this effect with m-trifluoromethyl-diphenyl diselenide (a), p-fluor-diphenyl diselenide (b), p-chloro-diphenyl diselenide (c), and p-methoxyl-diphenyl diselenide (d) in rat liver homogenate. We also investigated if the mechanisms involved in the antioxidant property of 2,2'-dipyridyl diselenide are the same that of other diselenides. Thiobarbituric acid reactive substances (TBARS) and protein carbonyl (PC) levels were determined in rat liver homogenate, as indicators of antioxidant activity. Dehydroascorbate (DHA) reductase- and glutathione S-transferase (GST)-like activities, 2,2'-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical-scavenging activities and the protection against the oxidation of Fe(2+) were determined to better understand the antioxidant property of compounds. δ-Aminolevulinic dehydratase (δ-ALA-D) activity was also carried out in rat liver homogenates, as a toxicological parameter. Compound e showed the highest potency in reducing TBARS (order of IC(50) values: e < b ≤ a < d ≤ c) and PC (order of IC(50) values: e < c ≤ b ≤ a < d) levels and lower potency in inhibiting δ-ALA-D activity than other diselenides. Compound e at all concentrations tested had no enzyme-mimetic property, but had radical-scavenging activity (≥5 µM) and protected against the oxidation of Fe(2+) (50 µM); while compounds a-d showed GST and DHA-mimetic activities and protected against the oxidation of Fe(2+), but had not radical-scavenging activities. This study indicates that (i) 2,2'-dipyridyl diselenide (e) had better in vitro antioxidant effect than other diselenides and lower inhibitory effect on δ-ALA-D activity, (ii) the presence of pyridine ring is responsible for the best antioxidant effect of this compound, and (iii) 2,2'-dipyridyl diselenide acts by different mechanisms of other diselenides.

Ebselen reduces hyperglycemia temporarily-induced by diazinon: a compound with insulin-mimetic properties.

The present study investigated the effect of ebselen (EB) against hyperglycemia induced by the organophosphate (OPI) diazinon (DI) in rats. The insulin-mimetic properties of EB were investigated in vitro with the aim of better understanding the hypoglycemic effect of this compound. The protective effect of EB against pancreatic and hepatic damage caused by DI in rats was also appraised. In the in vivo experiments, rats were pre-treated with a single injection of EB (50mg/kg, intraperitoneal, i.p.). Afterward, animals were treated with a single injection of DI (200 mg/kg, i.p.). The parameters indicative of pancreatic and hepatic damage such as, serum amylase, lipase, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) activities as well as serum glucose levels, hepatic glycogen content and glucose-6-phosphatase (G6Pase) activity were determined. EB pre-treatment was effective in reducing serum amylase, lipase, AST, ALT, ALP, and LDH activities, protecting against pancreatic and hepatic damage. EB reduced hyperglycemia and increased hepatic glycogen content in animals exposed to DI. In the in vitro assays, EB (150 µM) or insulin (IN 10 µM, positive control) was incubated with either skeletal muscle or hepatic tissue with the aim of measuring glucose uptake, glycogen synthesis and glycogen breakdown. EB increased the glucose uptake in skeletal muscle, stimulated hepatic glycogen synthesis and inhibited glycogen breakdown in a similar way to IN. In conclusion, EB, possibly through its insulin-mimetic action, protected against pancreatic and hepatic damage caused by DI in rats.

The potential antioxidant activity of 2,3-dihydroselenophene, a prototype drug of 4-aryl-2,3-dihydroselenophenes.

Here we present our results in palladium cross-coupling reaction of aryl boronic acids with 4-iodo-2,3-dihydroselenophene derivatives. The cross-coupled products were obtained in satisfactory yields. A dehydrogenation of 4,5-diphenyl-2,3-dihydroselenophene was activated by DDQ and the 2,3-diarylselenophene was obtained in good yield. Regarding the antioxidant activity, the selenophene derivative 3a was effective in counteracting lipid and protein oxidation as well as scavenging ABTS radical. The findings of the present study indicate that 3a is a prototype for future drug development programs to treat disorders mediated by reactive oxygen species.

Selective base-promoted synthesis of substituted selenophenes by carbocyclization of (Z)-benzylselenoenynes.

We herein described the synthesis of several 3-benzyl-2,5-diarylselenophene derivatives in moderate to good yields using (Z)-benzylselenoenynes as starting material in carbocyclization reactions. The reactions were carried out under mild conditions using only t-BuOK as base, in the complete absence of transition metals or additives. The cyclized 3-benzyl-2,5-diarylselenophenes obtained in the current protocol appear highly promising and attractive intermediates for the synthesis of polysubstituted selenophenes. For instance, 3-benzyl-2,5-diphenylselenophene was treated with Br(2) provided the corresponding 3-benzyl-4-bromo-2,5-diphenylselenophene in high yield. 4-Bromoselenophene derivative was applied as substrate in the palladium catalyzed cross-coupling reactions with boronic acids to give the Suzuki type products in excellent yields.

Diphenyl diselenide protects against glycerol-induced renal damage in rats.

In this study we evaluated the effect of diphenyl diselenide (PhSe)(2) on glycerol-induced acute renal failure in rats. Rats were pre-treated by gavage every day with (PhSe)(2 )(7.14 mg kg(-1)) for 7 days. On the eighth day, rats received an intramuscular injection of glycerol (8 mL kg(-1)). Twenty-four hours afterwards, rats were euthanized and the levels of urea and creatinine were measured in plasma. Catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), delta-aminolevulinate dehydratase (delta-ALA-D) and Na(+), K(+)-ATPase activities and ascorbic acid levels were evaluated in renal homogenates. Histopathological evaluations were also performed. The results demonstrated that (PhSe)(2) was able to protect against the increase in urea and creatinine levels and histological alterations in kidney induced by glycerol. (PhSe)(2) protected against the inhibition in delta-ALA-D, CAT and GPx activities and the reduction in ascorbic acid levels induced by glycerol in kidneys of rats. In conclusion, the present results indicate that (PhSe)(2) was effective in protecting against acute renal failure induced by glycerol.

Antidepressant-like effect of diphenyl diselenide on rats exposed to malathion: involvement of Na+K+ ATPase activity.

The antidepressant-like effect of repeated administration of diphenyl diselenide (PhSe)2 in rats exposed to malathion is reported. The role of Na+K+ ATPase, acetylcholinesterase (AChE) and monoamine oxidase (MAO) activities and oxidative stress in antidepressant behavior were investigated in cerebral cortex of rats. Rats were exposed once a day for 3 consecutive days to malathion (50mg/kg, intraperitoneal) and (PhSe)2 (50mg/kg, oral). To investigate the antidepressant-like behavior rats were submitted to the forced swimming test (FST) and open-field test (OFT). Thiobarbituric acid reactive species (TBARS) levels, enzymatic and non-enzymatic antioxidant defenses were carried out in cerebral cortex of rats. The results confirmed that malathion increased immobility time in the FST without altering the locomotor performance in the OFT. Treatment with (PhSe)2 ameliorated performance in the FST without altering the crossing numbers in the OFT. The inhibition of Na+K+ ATPase activity caused by malathion was prevented by treatment with (PhSe)2. Exposure to malathion did not alter parameters of oxidative stress as well as AChE and MAO activities in cerebral cortex of rats. In conclusion, (PhSe)2 exerted antidepressant-like effect in rats exposed to malathion. Na+K+ ATPase activity is, at least in part, involved in (PhSe)2 antidepressant-like behavior.