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Abstract

C-terminal amidation is a common feature of wild type membrane disrupting antimicrobial peptides (AMPs). Empirical evidence suggests that this modification increases antimicrobial efficacy. However, the actual role of C-terminal amidation in the molecular mechanism of action of AMPs is not fully understood. Amidation alters two key properties simultaneously: the net charge and helicity of the peptide, both of which are implicated in the mechanism of action. However, the differences between the physicochemical properties of the carboxyl and amide moieties have been disregarded in former studies. In this study we assessed whether the difference in activity is only caused by changes in the helicity and overall charge of a peptide, i.e. whether the chemistry of the terminus is otherwise irrelevant. To do so, the membrane disrupting activity of a modified aurein 1.2 peptide was studied in which a secondary amide was formed with a terminal methyl group, instead of the primary amide as in the wild type peptide. Results of quartz crystal microbalance, dye leakage and circular dichroism experiments show that the activity of the modified peptide is substantially reduced compared to the wild type peptide, in particular that the modified peptide exhibited a much-reduced ability to bind to the membrane. Thus, the primary amide at the C-terminus is required to bind to the membrane, and a secondary amide cannot serve the same purpose. We hypothesize that this difference is related to the hydration state of the terminus. The lack of membrane binding ability of the modified peptide identifies the primary amide moiety at the C terminus as a specific membrane binding motif.

Abstract

Objective: The objective of the study was to determine the differences in selected clinical variables and self-image in people with alcohol dependence differing in severity of physical, emotional and sexual abuse experienced before age 18.

Method: The study included 90 people with alcohol dependence. The following research tools were used: Early Trauma Inventory (ETI), Adjective Check List (ACL), MAST, SAAD, and a questionnaire designed by the authors. In order to identify groups with varying indices of physical, emotional and sexual childhood abuse, a cluster analysis method was used.

Results: Two groups of subjects with alcohol dependence were identified: Group 1 with high indices of physical, emotional and sexual childhood abuse and Group 2 with low indices. In terms of self-image the subjects in Group 1 compared to subjects in Group 2 were characterized by a lower self-esteem, self-acceptance, resistance to stress, less intense needs for achievement, endurance, order, nurturing others, interaction with opposite-sex partners, subordinations but more intense need for change. The age of alcohol use initiation and the onset of regular alcohol drinking was statistically significantly lower in Group 1. The severity of alcohol dependence was significantly lower in Group 2. The subjects in Group 1 significantly more frequently confirmed the history of a hereditary predisposition to alcohol dependence, suicidal ideation, suicide attempts and self-harm.

Discussion: The obtained results closely correspond to the data available in the literature.

Conclusions: An assessment of exposure to various forms of childhood abuse appears to be an indispensable element of collecting medical history of people with alcohol dependence.

Abstract

The use of a non-invasive approach to collect biological samples from natural populations represents a great means of gathering information while avoiding handling animals. Even if corticosterone is the main glucocorticoid investigated in birds, there has been observed a proportional direct link between corticosterone and cortisol concentrations. Dehydroepiandrosterone (DHEA) can be produced by the adrenal cortex and should have prominent antiglucocorticoid properties also in birds. The aim of this study was to verify if there is any difference in the cortisol and DHEA feather concentrations between clinically normal and physiologically compromised Griffon vultures (Gyps fulvus) through the non-invasive approach of collecting moulted feathers without having to pluck them from the bird. The study was carried out using 8 physiologically compromised (PC) Griffons and 9 clinically normal Griffons considered as the control (CTRL) group that were necropsied or from the wildlife rehabilitation centre. Primary and secondary covert feathers were either collected directly from the birds’ cage floors, or, in the case of dead Griffons, they were plucked off the animals. The results, obtained by RIA, revealed that both cortisol (P<0.01) and DHEA (P<0.05) feather concentrations were higher in the PC than in the CTRL group. No difference was observed by comparing the cortisol/DHEA ratio between the two evaluated groups (P=0.15). Pearson’s correlation coefficients showed no correlation between feather hormone concentrations in the PC group (r=0.01, P=0.96) while a positive correlation in the CTRL group (r=0.65, P=0.006) was observed. In conclusion, our study reveals that moulted feathers can be a non-invasive and an interesting tool to evaluate the allostatic load of wild birds and they allowed better understanding the relationship between hormones of the hypothalamic–pituitary–adrenal axis and the physiological status of the birds.

Abstract

The aim of the study was to assess the gut microbiota and selected haematological and biochemical blood parameters of weaned piglets following dietary supplementation with a probiotic and vitamin C. the piglets were divided into a control group (group C) and an experimental group (group E), with 30 piglets in each group. All animals received the same feed ad libitum. The animals in the control group (group C) received feed with no added probiotic and vitamin C. the piglets in the experimental group (group E) were given a supplement containing a probiotic (Bacillus cereus 1×109 CFU/kg) in the amount of 1.5 g/piglet/day and vitamin c in the amount of 300 mg/piglet/day. The supplement was administered for 28 days. The total numbers of bacteria of the family Enterobacteriaceae and of the genus Lactobacillus were determined in faeces. The erythrocyte count, haemoglobin level, haematocrit, leukocyte count, and percentages of neutrophils and lymphocytes were determined in the blood. The biochemical analysis concerned the concentration of triacylglycerols, total cholesterol, and LDL and HDL cholesterol. In group E a significant decrease (P<0.01) in the total number of Enterobacteriaceae bacteria was observed in the faeces of the piglets, accompanied by an increase in the number of lactobacilli relative to group C. E. coli was found to predominate over other microorganisms. Salmonella choleraesuis bacteria were present in the faeces of both groups before administration of the supplement, but were not found after its use. The supplement with probiotic and vitamin C caused a significant increase in the erythrocyte, haemoglobin and haematocrit levels in the blood of the piglets and a significant decrease in the concentration of triacylglycerols, total cholesterol and LDL cholesterol.

Abstract

Objective. Olanzapine (OLA), amisulpride (AMI), aripiprazole (ARI), and quetiapine (QUE) belong to antipsychotics, which administration represents still most reliable way for the treatment of schizophrenic and bipolar disorders. The intention of the present study was to explore whether the acute administration of a particular antipsychotic, indicated by the presence of c-Fos, will: a) stimulate neurons already activated by a long lasting homogeneous or heterogeneous stress preconditioning, indicated by the FosB/ΔFosB (ΔFosB) expression, or b) have a stimulatory effect only on a not activated, so called silent neurons. The pattern of ΔFosB and c-Fos spatial relationship was investigated in three forebrain structures, including the septal ventrolateral nucleus (seVL), the striatal dorsolateral area (stDL), and the shell of the nucleus accumbens (shell).

Methods. The rats were divided into 10 groups and exposed to two types of stressors. Half of them was exposed to a sequence of homogeneous stressor – handling (HDL) and the other half to a heterogeneous stressor (CMS) daily for 20 days. CMS consisted of five types of stressors: crowding, air-puff, wet bedding, predator stress, and forced swimming applied in an unexpected order. On the 21st day of the experiment, the rats were free of the stress exposure and on the 22nd day, both groups of animals receive a single intraperitoneal injection of vehicle (4% DMSO in saline, 0.1 ml/100 g) or OLA (5 mg/kg), AMI (20 mg/kg), ARI (10 mg/kg), and QUE (15 mg/kg). 90 min after the drugs administration the animals were transcardially perfused, brains removed, cut into 30 µm thick coronal sections, and double stained: first with ΔFosB antibody linked with Alexa488 fluorescent dye and second with c-Fos antibody linked to Alexa596 one. Quantitative evaluation of ΔFosB and c-Fos colocalizations was performed on fluorescence photomicrographs transformed into a final picture containing only yellow, green, and red colored circles.

Results. The data of this investigation demonstrate that ΔFosB and c-Fos colocalizations occurred in each of the three areas investigated, i.e. seVL, stDL, and shell ones, in both HDL as well as CMS preconditioned rats. The levels of ΔFosB and c-Fos colocalizations varied in the individual forebrain areas studied. From the total 22 areas measured, level of c-Fos colocalization prevailed over ΔFosB in 18 ones. However, neither c-Fos nor ΔFosB reached 100% level of colocalization in any of the forebrain areas investigated.

Conclusion. The present findings indicate that ΔFosB and c-Fos colocalizations occurred in each of the three areas investigated, i.e. seVL, stDL, and shell, in both HDL and CMS preconditioned rats, whereas the parallel occurrence of free c-Fos as well as c-Fos colocalized with ΔFosB might speak out for a possible involvement of the c-Fos activated by antipsychotics applied in dual, i.e. short- and long-lasting, functions.

Abstract

Objectives. Bisphenol A (BPA) has been reported that among other male reproductive dys-functions, it can cause marked estrogenic effects including alteration in serum hormones as well as testicular lesions in exposed animals. This work sought to study the role of gallic acid (GA), a known antioxidant, on the BPA-induced testicular oxidative stress in adult male Wistar rats using serum hormone analysis, histopathology, and biochemical assays.

Methods. Adult male rats were divided into four groups (n=10) including control (0.2 ml of corn oil), GA (20 mg/kg/day), BPA (10 mg/kg/day), BPA+GA (BPA, 10 mg/kg/day + GA, 20 mg/kg/day). All medications were given by oral gavage for 45 consecutive days. The body and testicular weights were measured. Blood and organ samples were collected for the serum hormonal assay: testosterone (T), luteinizing hormone (LH), follicle stimulating hormone (FSH) and prolactin (PRL), and tissue biochemistry analysis: superoxide dismutase (SOD), reduced glutathione (GSH), glutathione-S-transferase (GST), malondialdehyde (MDA), hydrogen peroxide (H2O2), respectively.

Results. The BPA-treated rats showed significant reduction in the gonadosomatic index. BPA also caused significant decrease in the levels of the serum testosterone and prolactin. Furthermore, BPA induced testicular oxidative stress by decreasing the activities of antioxidant enzymes and increasing reactive oxygen species. However, co-treatment with GA protected against these alterations.

Conclusion. Findings from the present study confirmed the previously reported data and show that the ability of GA, as a potent antioxidant, may protect against BPA-induced alterations in the male reproductive function. Hence, GA protects against testicular oxidative stress in adult male Wistar rats following chronic exposure to BPA.

Abstract

Nuclear Expressed Sequence Tag (EST) microsatellite markers were developed for the Tasmanian palaeoendemic conifer Lagarostrobos franklinii (Hook.-f.) Quinn for genetic studies. RNAseq data was mined for EST microsatellites, and primer pairs were synthesised from 70 contigs with 50 producing amplification products. Of these 50, 10 reliably amplified and displayed polymorphism across 8 samples representing the entire species range. The genetic diversity of these 10 loci was then examined in three wild populations (84 samples). The number of alleles varied from two to thirteen per locus with the average number of alleles per population ranging between 3.0 – 4.7. Observed and expected heterozygosity ranged from 0.34 – 0.42 and 0.37 – 0.44, respectively. Marker cross-amplification was tested in the New Zealand sister species Manoao colensoi (Hook. f.) Molloy, but no markers amplified reliably, which possibly reflects the age of divergence between these species (~64 million years). These are the first microsatellite markers developed for the monotypic genus Lagarostrobos. They will be valuable for assessing the species extant genetic diversity, the impact of past climatic perturbations and human disturbance and the role of clonal propagation in recruitment.

Abstract

The aim of the study was to compare the content of selected bioactive whey proteins and lipophilic vitamins, which largely determine the bioactive status of milk, in milk obtained from local breeds of cows raised in Poland (Polish Red, White-Backed and Simmental) and Polish Holstein-Friesian cows. Basic chemical composition and content of selected bioactive compounds (β-lactoglobulin, α-lactalbumin, lactoferrin, bovine serum albumin, and vitamins: E, A, D3 and β-carotene) in 550 milk samples were analysed. The milk produced by local breeds proved to be a more valuable source of whey proteins and lipophilic vitamins than that of the Polish Holstein-Friesians. It was distinguished by its content of all bioactive compounds, including those with antioxidant properties, i.e. vitamins E, A and D3 and β-lactoglobulin, and antimicrobial properties, mainly lactoferrin. Therefore, the milk of cows of local breeds should be considered a valuable material for processing, especially at the level of the farm or small local processing plant, to produce products that are richer in health-promoting compounds. The promotion of milk from local breeds can therefore be an opportunity for the farms that raise them.

Abstract

The aim of the study was to test whether the use of probiotic bacteria Bacillus subtilis or Enterococcus faecium or a phytobiotic containing cinnamon oil can improve the metabolic parameters, immune status, gut microbiota and histology, and growth performance of broiler chickens. The experiment was carried out on 560 one-day-old male Ross 308 broiler chickens raised until the age of 42 days. The broiler chickens were assigned to 4 experimental groups of 140 birds each (7 replications of 20 individuals each). The control group (Control) did not receive additives. A probiotic preparation containing live bacterial cultures of Enterococcus faecium (EF, in the amount of 0.25 g/l) or Bacillus subtilis (BS, 0.25 g/l) or a phytobiotic preparation containing cinnamon oil (OC, 0.25 ml/l) was administered to the broiler chickens with their drinking water throughout the rearing period. The most important results indicate that the use of BS and OC resulted in: a significant (P≤0.05) increase in the level of ferric reducing ability of plasma (FRAP), high-density cholesterol (HDL) and glutathione (GSH + GSSH) and a significant (P≤0.05) decrease in the level of malondialdehyde (MDA), lipid hydroperoxides (LOOH), total cholesterol (TC), triacylglycerols (TAG), nonesterified fatty acids (NEFA) and interleukin 6 (IL-6), a ratio of heterophils : leukocytes (H:L) and alkaline phosphatase (ALP) activity, alanine aminotransferase (ALT), acidic phosphatase (AC) and creatinine kinase (CK), relative to the C group. In the blood of broiler chickens from the OC treatment, aspartate aminotransferase (AST), lactate dehydrogenase activity and 3-hydroxy-butyrate dehydrogenase (HBDH) significantly (P≤0.05) decreased in relation to the C group, and in broiler chickens from EF and BS treatments there was an increase (P≤0.05) in haemoglobin (Hb) content. Compared with group C, in the broiler chickens’ nutritional content from EF, BS and OC treatments, the total number of coliforms and number of fungi significantly (P≤0.05) dropped and the number of aerobic bacteria increased (P≤0.05) in the length of the villus and the depth of the crypt. It has been found that Bacillus subtilis, Enterococcus faecium and phytobiotic containing cinnamon oil can improve the microbiological and histological appearance of broiler chicken intestine. The addition of probiotic bacteria Bacillus subtilis or phytobiotic containing cinnamon oil to drinking water is more preferable than Enterococcus faecium regarding stimulation of the immune system, blood redox status parameters, parameters of metabolic changes and the gut microbiome and morphometry.

Abstract

The degree of flesh pigmentation is one of the most important quality criteria dictating the fish market value. It is well known that fish, like other animals, cannot synthesize their own coloring pigments de novo, and must obtain these pigments from their diet. In this study, four levels of black mulberry (Morus nigra) juice powder (BMP) as a natural pigment source were incorporated into a basal diet at concentrations of 0, 0.25, 0.5, and 0.75% and fed to rainbow trout weighing 100±5 g for 8 weeks in triplicate. At the end of the feeding trial, the effect of BMP on growth performance, blood biochemical parameters and fillet color was examined. Fish fed BMP showed significant enhancements in weight gain (WG), specific growth (SGR), food conversion ratio (FCR), and survival rates (SR) (P<0.05). SGR, WG and SR values were increased significantly following dietary supplementation with BMP in a dose dependent manner with the highest values in fish fed 0.75%, while the FCR was decreased (P<0.05). Body crude protein, lipid, and moisture contents were increased significantly in fish fed BMP (P<0.05). Dietary BMP has significantly decreased the levels of blood ALT, AST, and glucose (P>0.05). While the blood carotenoid concentration was increased in fish fed 0.5% BMP compared to other treated groups. Fish fed BMP showed increased fillet yellowness (b*) and redness (a*), while the fillet lightness (L*) was decreased when compared to the control (P<0.05). In conclusion, diets supplemented with BMP increased the growth performance, muscle pigmentation, and health status of rainbow trout.