First isolation and molecular characterization of pseudorabies virus detected in Turkey

Background

Pigs are the main host species for the pseudorabies virus. It causes fatal encephalitis in many species, including humans. This article aims to report the first clinical case of pseudorabies as well as isolation and molecular characterization of the virus from a hunting dog in Bursa province, Turkey.

Methods and results

The dog shows clinical signs including pruritus and neurological signs such as stumbling and inability to stand up compatible with pseudorabies. The virus isolates were obtained from the supernatant of fresh tissue samples from the cerebellum, cornu ammonis, spleen, salivary gland, conjunctival swab, serum, and PBMC samples. The glycoprotein C region is targeted for viral DNA amplification. Pseudorabies virus genome detected both in fresh tissues and supernatants of third passage on Vero cells. The number of PCR positive samples was dramatically increased after cell culture inoculations. Genome sequencing of strain Bursa-10303, which was isolated from a non-endemic area, identified it to belong to clade A.

Conclusions

This study confirms the possible presence of pseudorabies infection in the wildlife reservoirs in Turkey. Future studies may clarify the importance of the infection in Turkey region, where there is no prevalent pig production.

     

Genetic impacts of Anacapa deer mice reintroductions following rat eradication

The Anacapa deer mouse is an endemic subspecies that inhabits Anacapa Island, part of Channel Islands National Park, California. We used mitochondrial DNA cytochrome c oxidase subunit II gene (COII) and 10 microsatellite loci to evaluate the levels of genetic differentiation and variation in ~1400 Anacapa deer mice sampled before and for 4 years after a black rat (Rattus rattus) eradication campaign that included trapping, captive holding and reintroduction of deer mice. Both mitochondrial and microsatellite analyses indicated significant differentiation between Anacapa deer mice and mainland mice, and genetic variability of mainland mice was significantly higher than Anacapa mice even prior to reintroduction. Bayesian cluster analysis and Principal Coordinates Analysis indicated that East, Middle and West Anacapa mice were genetically differentiated from each other, but translocation of mice among islands resulted in the East population becoming less distinct as a result of management. Levels of heterozygosity were similar before and after management. However, numerous private alleles in the founder populations were not observed after reintroduction and shifts in allele frequencies occurred, indicating that the reintroduced populations experienced substantial genetic drift. Surprisingly, two mitochondrial haplotypes observed in an earlier study of Anacapa deer mice were lost in the 20 years prior to the rat eradication program, leaving only a single haplotype in Anacapa deer mice. This study demonstrates how genetic monitoring can help to understand the re-establishment of endemic species after the eradication of invasive species and to evaluate the effectiveness of the management strategies employed.     

The effects of isoniazid on hippocampal NMDA receptors: Protective role of Erdosteine

Isoniazid (INH) has neurotoxic effects such as seizure, poor concentration, subtle reduction in memory, anxiety, depression and psychosis. INH-induced toxic effects are thought to be through increased oxidative stress, and these effects have been shown to be prevented by antioxidant therapies in various organs. Increased oxidative stress may be playing a role in these neurotoxic effects. N-methyl D-aspartat receptors (NMDA) are a member of the ionotropic group of glutamate receptors. These receptors are involved in a wide variety of processes in the central nervous system including synaptogenesis, synaptic plasticity, memory and learning. Erdosteine is a potent antioxidant and mucolytic agent. We aimed to investigate adverse effects of INH on rat hippocampal NMDAR receptors, and to elucidate whether erdosteine prevents possible adverse effects of INH. In the present study, compared to control group, NMDAR2A (NR2A) receptors were significantly decreased and malondialdehyde (MDA), end product of lipid peroxidation, production was significantly increased in INH-treated group. On the other hand, administration of erdosteine to INH-treated group significantly increased NR2A receptors and decreased MDA production. In conclusion, decreasing NR2A receptors in hippocampus and increasing lipid peroxidation correlates with the degree of oxidative effects of INH and erdosteine protects above effect of INH on NR2A receptors and membrane damage due to lipid peroxidation by its antioxidant properties.     

Human and murine paraoxonase 1 are host modulators of Pseudomonas aeruginosa quorum-sensing

The pathogenic bacterium Pseudomonas aeruginosa uses acyl-HSL quorum-sensing signals to regulate genes controlling virulence and biofilm formation. We found that paraoxonase 1 (PON1), a mammalian lactonase with an unknown natural substrate, hydrolyzed the P. aeruginosa acyl-HSL 3OC12-HSL. In in vitro assays, mouse serum-PON1 was required and sufficient to degrade 3OC12-HSL. Furthermore, PON2 and PON3 also degraded 3OC12-HSL effectively. Serum-PON1 prevented P. aeruginosa quorum-sensing and biofilm formation in vitro by inactivating the quorum-sensing signal. Although 3OC12-HSL production by P. aeruginosa was important for virulence in a mouse sepsis model, Pon1-knock-out mice were paradoxically protected. These mice showed increased levels of PON2 and PON3 mRNA in epithelial tissues suggesting a possible compensatory mechanism. Thus, paraoxonase interruption of bacterial communication represents a novel mechanism to modulate quorum-sensing by bacteria. The consequences for host immunity are yet to be determined.     

Steady-state kinetic properties of sorbitol dehydrogenase from chicken liver

The steady-state kinetic properties of partially purified chicken liver sorbitol dehydrogenase (SDH) were determined spectrophotometrically at 25 degrees C, in 50 mM 3-(N-morpholino)propanesulfonic acid (MOPS) buffer, pH 8.0. In the sorbitol-to-fructose direction, analysis was based on initial rate data obtained at [NAD(+)](o)=0.1-0.4 mM and [sorbitol](o)=1.25-10 mM. The reverse process was analyzed by recording progress curves for NADH consumption, starting with [NADH](o)=0.2 mM and [fructose](o)=66.7-267 mM. The kinetics conformed to an ordered sequential model, with the cofactors adding first. The steady-state parameters in the forward direction, K(NAD(+)), K(iNAD(+)) and K(sorbitol), were found to be 210+/-62 muM, 220+/-69 microM and 3.2+/-0.54 mM, respectively. The corresponding parameters in the reverse direction were K(NADH)=240+/-58 microM, K(iNADH)=10+/-2.8 microM and K(fructose)=1000+/-140 mM. The results indicated a close parallelism with human SDH, yet up to 40-fold differences were observed when compared to related reports on other mammalian species. The structural and adaptive bases of the variation in substrate and cofactor affinities need to be accounted for.     

Amelioration of sepsis-induced hepatic and ileal injury in rats by the leukotriene receptor blocker montelukast

Background: Sepsis is a generalized inflammatory response, which involves organ systems remote from the locus of the initial infectious insult, involves the release of cytokines and the subsequent formation of reactive oxygen and nitrogen species.Objective: The aim of this study was to investigate the possible protective effect of montelukast, a leukotriene receptor blocker, against oxidative damage in the liver and ileum of septic rats.Methods: Sepsis was induced by cecal ligation and puncture method in female Wistar albino rats. Sepsis and sham operated (control) groups received either saline or montelukast (10 mg/kg, ip) immediately after the operation and at 12 h. Twenty-four hours after the surgery, rats were decapitated and malondialdehyde (MDA) content—an index of lipid peroxidation, glutathione (GSH) levels—a key antioxidant, myeloperoxidase (MPO) activity—an index of neutrophil infiltration, and collagen contents were determined in the liver and ileum. Formation of reactive oxygen species in liver and ileal tissue samples was monitored by using chemiluminescence (CL) technique with luminol and lucigenin probes. Both tissues were also analyzed histologically. Serum lactate dehydrogenase (LDH) and tumor necrosis factor-α (TNF-α) level were assessed in trunk blood.Results: Sepsis resulted in decreased GSH levels, and increased MDA levels, MPO activity, CL levels and collagen contents in both the liver and the ileum (P<0.05–P<0.001) indicating the presence of the oxidative damage. Similarly, serum TNF-α and LDH were elevated in the sepsis group as compared to control group. On the other hand, montelukast treatment reversed all these biochemical indices, as well as histopathological alterations, which were induced by sepsis.Conclusion: Findings of the present study suggest that montelukast possesses an anti-inflammatory effect on sepsis-induced hepatic and intestinal damage and protects against oxidative injury by a neutrophil-dependent mechanism.     

A New Method for Purification of Carbonic Anhydrase Isozymes by Affinity Chromatography

A new affinity gel for purification of carbonic anhydrase isozymes was prepared using EUPERGIT C-250L derivatized with p-aminobenzenesulfonamide, an inhibitor of carbonic anhydrase. The binding capacity of the affinity gel was determined at different temperatures, pH values, elution buffers, and ionic strengths. Human carbonic anhydrase isozymes (HCA I and HCA II) and bovine carbonic anhydrase (BCA) were purified in high yields from erythrocytes.     

Mesna (2-mercaptoethane sulfonate) prevents ischemia/reperfusion induced renal oxidative damage in rats

Reoxygenation of the ischemic tissue promotes the generation of various reactive oxygen metabolites (ROM) which are known to have deleterious effects on various cellular functions. This study was designed to determine the possible protective effect of mesna (2-Mercaptoethane Sulfonate) on renal ischemia/reperfusion (I/R) injury. Wistar albino rats were unilaterally nephrectomized, and 15 days later they were subjected to 45 min of renal pedicle occlusion followed by 6 h of reperfusion. Mesna (MESNA, 150 mg/kg, i.p.; an effective dose against I/R injury) or vehicle was administered twice, 15 min prior to ischemia and immediately before the reperfusion period. At the end of the reperfusion period, rats were killed by decapitation. Kidney samples were taken for histological examination or determination of the free radicals, renal malondialdehyde (MDA) and glutathione (GSH) levels, and myeloperoxidase (MPO) activity. Renal tissue collagen content, as a fibrosis marker was also determined. Creatinine and urea concentrations in blood were measured for the evaluation of renal function. The results demonstrated that renal I/R caused nephrotoxicity, as evidenced by increases in blood urea and creatinine levels, which was reversed by MESNA treatment. Increased free radical levels, as assessed by nitroblue-tetrazolium test were reduced with MESNA. Moreover, the decrease in GSH and increases in MDA levels, and MPO activity induced by I/R indicated that renal injury involves free radical formation. Treatment of rats with MESNA restored the reduced GSH levels while it decreased MDA levels as well as MPO activity. Increased collagen contents of the kidney tissues by I/R were reversed back to the control levels by MESNA treatment. Since MESNA administration reversed these oxidant responses, improved renal function and microscopic damage, it seems likely that MESNA protects kidney tissue against I/R induced oxidative damage.