Biological time-dependent difference in effect of peroxynitrite demonstrated by the mouse hot plate pain model

We previously demonstrated the rhythmic pattern of L-arginine/nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) cascade in nociceptive processes. The coupled production of excess NO and superoxide leads to the formation of an unstable intermediate peroxynitrite, which is primarily responsible for NO-mediated toxicity. In the present study, we evaluated the biological time-dependent effects of exogenously administered peroxynitrite on nociceptive processes and peroxynitrite-induced changes in the analgesic effect of morphine using the mouse hot-plate pain model. Experiments were performed at four different times of day (1, 7, 13, and 19 hours after lights on, i.e., HALO) in mice of both sexes synchronized to a 12 h:12 h light-dark cycle. Animals were injected intraperitoneally (i.p.) with saline or 10 mg/kg morphine 30 min before and 0.001 mg/kg peroxynitrite 30 sec before hot-plate testing, respectively. The analgesic effect of morphine exhibited significant biological time-dependent differences in the thermally-induced algesia; whereas, administration of peroxynitrite alone exhibited either significant algesic or analgesic effect, depending on the circadian time of its injection. Concomitant administration of peroxynitrite and morphine reduced morphine-induced analgesia at three of the four different study time points. In conclusion, peroxynitrite displayed nociceptive and antinociceptive when administered alone according to the circadian time of treatment, while it diminished analgesic activity when administered in combination with morphine at certain biological times.     

Olive mill wastewater treatment in single-chamber air-cathode microbial fuel cells

Olive mill wastewaters create significant environmental issues in olive-processing countries. One of the most hazardous groups of pollutants in these wastewaters is phenolic compounds. Here, olive mill wastewater was used as substrate and treated in single-chamber air-cathode microbial fuel cells. Olive mill wastewater yielded a maximum voltage of 381 mV on an external resistance of 1 kΩ. Notable decreases in the contents of 3,4-dihydroxybenzoic acid, tyrosol, gallic acid and p-coumaric acid were detected. Chemical oxygen demand removal rates were 65 % while removal of total phenolics by the process was lower (49 %). Microbial community analysis during the olive mill wastewater treating MFC has shown that both exoelectrogenic and phenol-degrading microorganisms have been enriched during the operation. Brevundimonas-, Sphingomonas- and Novosphingobium-related phylotypes were enriched on the anode biofilm, while Alphaproteobacteria and Bacteriodetes dominated the cathode biofilm. As one of the novel studies, it has been demonstrated that recalcitrant olive mill wastewaters could be treated and utilized for power generation in microbial fuel cells.     

Assessment of Atrial Electromechanical Delay by Tissue Doppler Echocardiography in Obese Subjects

Our aim was to evaluate whether atrial electromechanical delay measured by tissue Doppler imaging (TDI), which is an early predictor of atrial fibrillation (AF) development, is prolonged in obese subjects. A total of 40 obese and 40 normal‐weight subjects with normal coronary angiograms were included in this study. P‐wave dispersion (PWD) was calculated on the 12‐lead electrocardiogram (ECG). Systolic and diastolic left ventricular (LV) functions, inter‐ and intra‐atrial electromechanical delay were measured by TDI and conventional echocardiography. Inter‐ and intra‐atrial electromechanical delay were significantly longer in the obese subjects compared with the controls (44.08 ± 10.06 vs. 19.35 ± 5.94 ms and 23.63 ± 6.41 vs. 5.13 ± 2.67 ms, P < 0.0001 for both, respectively). PWD was higher in obese subjects (53.40 ± 5.49 vs. 35.95 ± 5.93 ms, P < 0.0001). Left atrial (LA) diameter, LA volume index and LV diastolic parameters were significantly different between the groups. Interatrial electromechanical delay was correlated with PWD (r = 0.409, P = 0.009), high‐sensitivity C‐reactive protein (hsCRP) levels (r = 0.588, P < 0.0001). Interatrial electromechanical delay was positively correlated with LA diameter, LA volume index, and LV diastolic function parameters consisting of mitral early wave (E) deceleration time (DT) and isovolumetric relaxation time (IVRT; r = 0.323, P = 0.042; r = 0.387, P = 0.014; r = 0.339, P = 0.033; r = 0.325, P = 0.041; respectively) and, negatively correlated with mitral early (E) to late (A) wave ratio (E/A) (r = ?0.380, P = 0.016) and myocardial early‐to‐late diastolic wave ratio (E_m/A_m) (r = ?0.326, P = 0.040). This study showed that atrial electromechanical delay is prolonged in obese subjects. Prolonged atrial electromechanical delay is due to provoked low‐grade inflammation as well as LA enlargement and early LV diastolic dysfunction in obese subjects.     

Behavioral interference and facilitation in the foraging cycle shape the functional response

Individual forager behaviors should affect per capita intakerates and thereby population and consumer-resource properties.We consider and incorporate conspecific facilitation and interferenceduring the separate foraging-cycle stages in a functional responsemodel that links individual behavioral interactions with consumer-resourceprocesses. Our analyses suggest that failing to properly considerand include all effects of behavioral interactions on foraging-cyclestage performances may either over- or underestimate effectsof interactions on the shape of both functional responses andpredator zero-growth isoclines. Incorporation of prey- and predator-dependentinteractions among foragers in the model produces predator isoclineswith potentials for highly complex consumer-resource dynamics.Facilitation and interference during the foraging cycle aretherefore suggested as potent behavioral mechanisms to causepatterns of community dynamics. We emphasize that correct estimationsof interaction-mediated foraging-cycle efficiencies should beconsidered in empirical and theoretical attempts to furtherour understanding of the mechanistic link between social behaviorsand higher order processes.     

Diversity of lacewing assemblages (Neuropterida:Neuroptera) in different forest habitats and agricultural areas in the East Mediterranean area of Turkey

The objectives of this study were to understand lacewing diversity patterns and the role of environmental factors in determining lacewing diversity in four habitat types: agricultural area (crops and orchards), pine forest (Pinus nigra Arnold and, Pinus brutia Ten), natural forest (cedar and willow‐oak), and mixed forest (beech and oak). Several diversity patterns were evaluated, including evenness and dominance, in the East Mediterranean area of Turkey by analyzing the abundance and species composition of lacewing assemblages using the Simpson and Shannon Diversity Indices. It was questioned whether these communities are structured according to environmental conditions such as altitude, temperature, rainfall, wind and humidity. This question was explored using generalized linear models (GLMs) and principal component analysis (PCA) to detect the effect of ecological parameters on the species composition of the lacewing assemblages. The data suggest that the species abundance, composition, and diversity of lacewings are affected by different forest and agricultural habitat types. Based on the results of the present study, it is recommended that the area of farmland under cultivation is decreased and the area of sustainably managed forest and agricultural land is increased in order to better protect lacewing diversity in the East Mediterranean area of Turkey.     

Effects on rat testes of the thiosemicarbazone derivative Schiff base (4-(1-phenylmethylcyclobutane-3-yl)-2-(2-hydroxybenzylidenehydrazino)thiazole) and its cadmium(II) complex

The aim of this study was to investigate structural and biochemical changes in testes of rats treated with the thiosemicarbazone derivative thiazole ring Schiff base, (4-(1-phenyl-methylcyclobutane-3-yl)-2-(2-hydroxybenzylidene-hydrazino) thiazole (L), and its Cd(II) complex (CdL(2)). The animals were divided into three groups. Group I was designated as control. The rats in groups II and III were injected subcutaneously with L or CdL(2) respectively at 150-mg kg(-1) doses at 3-day intervals for 15 days. At the end of the study, blood samples were collected for biochemical analysis, and testes were removed for histological examinations. Serum levels of vitamin A, E and MDA of the L-injected group were similar to the control group. While CdL(2) treatment decreased serum vitamin A and E levels, it increased the MDA level compared to other groups. Histologically, the testes structures of L-treated animals were similar to the control. Spermatogenic cells in seminiferous tubules of CdL(2)-treated animals displayed necrosis. Nuclei of spermatogonia and primary spermatocytes were pyknotic and heterochromatic. Homogenous pink particles were present in place of the spermatids. The interstitial areas were oedematous and intertubular vessels were plugged. In conclusion, the present results indicate that L does not cause biochemical and morphological alterations, but its Cd(II) complex has degenerative effects in normal rat testes.     

Selenium Induces Manganese-dependent Peroxidase Production by the White-Rot Fungus Bjerkandera adusta (Willdenow) P. Karsten

In this study, selenium (Se) induction of the ligninolytic enzyme manganese-dependent peroxidase (MnP) production, and the effects on the oxidative state in the white-rot fungus Bjerkandera adusta (Willdenow) P. Karsten were demonstrated. Low concentration of Se (0.5 mM) caused up to a twofold increase in MnP production (0.81 +/- 0.05 U/ml) when compared to control (0.39 +/- 0.07 U/ml), whereas higher concentrations of Se (200 mM) inhibited (0.03 +/- 0.01 U/ml) MnP production. Addition of high concentration of Se also caused up to a twofold increase in lipid peroxidation levels. These results demonstrate for the first time that Se may induce or reduce MnP production and lipid peroxidation levels which play a significant role in lignin degradation by white-rot fungi.     

iPBS-Retrotransposons-based genetic diversity and relationship among wild annual Cicer species

Lack of requisite genetic variation in cultivated species has necessitated systematic collection, documentation and evaluation of wild Cicer species for use in chickpea variety improvement programs. Cicer arietinum has very narrow genetic variation, and the use of a wild relative in chickpea breeding could provide a good opportunity for increasing the available genetic variation of cultivated chickpea. Genetic diversity and the relationship of 71 accessions, from the core area of chickpea origin and domestication (Southeastern Turkey), belonging to five wild annual species and one cultivated species (Cicer arietinum) were analysed using iPBS-retrotransposon and ISSR markers. A total of 136 scorable bands were detected using 10 ISSR primers among 71 accessions belonging to 6 species, out of which 135 were polymorphic (99.3 %), with an average of 13.5 polymorphic fragments per primer, whereas iPBS detected 130 bands with 100 % polymorphism with an average of 13.0 bands per primer. C. echinospermum and C. pinnatifidum were the most diverse among species, whereas C. arietinum exhibited lower polymorphism. The average polymorphism information contents (PIC) value for both marker systems was 0.91. The clustering of the accessions and species within groups was almost similar, when iPBS and ISSR NeighborNet (NNet) planar graphs were compared. Further detailed studies are indispensable in order to collect Cicer germplasm, especially C. reticulatum, from southeastern Turkey particularly, from Karacada? Mountain for preservation, management of this species, and to study their genetic diversity at molecular level. This study also demonstrates the utility and role of iPBS-retrotransposons, a dominant and ubiquitous part of eukaryotic genomes, for diversity studies in wild chickpea and in cultivated chickpea.     

The interrelations of radiologic findings and mechanical ventilation in community acquired pneumonia patients admitted to the intensive care unit: a multicentre retrospective study

Background

Burkholderia cepacia complex (BCC) bacteria are highly virulent, typically multidrug-resistant, opportunistic pathogens in cystic fibrosis (CF) patients and other immunocompromised individuals. B. vietnamiensis is more often susceptible to aminoglycosides than other BCC species, and strains acquire aminoglycoside resistance during chronic CF infection and under tobramycin and azithromycin exposure in vitro, apparently from gain of antimicrobial efflux as determined through pump inhibition. The aims of the present study were to determine if oxidative stress could also induce aminoglycoside resistance and provide further observations in support of a role for antimicrobial efflux in aminoglycoside resistance in B. vietnamiensis.

Findings

Here we identified hydrogen peroxide as an additional aminoglycoside resistance inducing agent in B. vietnamiensis. After antibiotic and hydrogen peroxide exposure, isolates accumulated significantly less [³H] gentamicin than the susceptible isolate from which they were derived. Strains that acquired aminoglycoside resistance during infection and after exposure to tobramycin or azithromycin overexpressed a putative resistance-nodulation-division (RND) transporter gene, amrB. Missense mutations in the repressor of amrB, amrR, were identified in isolates that acquired resistance during infection, and not in those generated in vitro.

Conclusions

These data identify oxidative stress as an inducer of aminoglycoside resistance in B. vietnamiensis and further suggest that active efflux via a RND efflux system impairs aminoglycoside accumulation in clinical B. vietnamiensis strains that have acquired aminoglycoside resistance, and in those exposed to tobramycin and azithromycin, but not hydrogen peroxide, in vitro. Furthermore, the repressor AmrR is likely just one regulator of the putative AmrAB-OprM efflux system in B. vietnamiensis.