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Naltrexone attenuates endoplasmic reticulum stress induced hepatic injury in mice
No full textEndoplasmic reticulum (ER) stress provides abnormalities in insulin action, inflammatory responses, lipoprotein B100 degradation and hepatic lipogenesis. Excess accumulation of triglyceride in hepatocytes may also lead to disorders such as non-alcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Opioid peptides are involved in triglyceride and cholesterol dysregulation, inflammation and cell death. In this study, we evaluated Naltrexone effects on ER stress induced liver injury. To do so, C57/BL6 mice received saline, DMSO and Naltrexone, as control groups. ER stress was induced by tunicamycin (TM) injection. Naltrexone was given before TM administration. Liver blood flow and biochemical serum analysis were measured. Histopathological evaluations, TNF-α measurement and Real-time RT-PCR were also performed. TM challenge provokes steatosis, cellular ballooning and lobular inflammation which significantly reduced in Naltrexone treated animals. ALT, AST and TNF-α increased in the TM group and improved in the Naltrexone plus TM group. Triglyceride and cholesterol levels decreased in TM treated mice with no increase in Naltrexone treated animals. In the Naltrexone plus TM group, gene expression of Bax/Bcl-2 ratio and caspase3 significantly lowered compared with the TM group. In this study, we found that Naltrexone had a notable alleviating role in ER stress induced steatosis and liver injury
Influence of l-carnosine on pro-antioxidant status in elite kayakers and canoeists
No full textCarnosine is a dipeptide formed from the amino acids β-alanine and histidine and found in large amounts in the brain and muscle, especially fast twitch muscle. Carnosine has an antioxidant role and accounts for about 10% of the muscle’s ability to buffer the H+ ions produced by high intensity exercise. Due to the interesting role of carnosine, the aim of the study was observe the effects of carnosine intake on pro-antioxidant status in highly trained athletes exposed to intense exercise.Fourteen male athletes from the Polish national kayak and canoe teams participated in placebo-controlled and cross-over study. The athletes were supplemented with 4 g/d carnosine for 14 days. Blood samples were collected before and 30 min, 24 h and 48 h after 2000 m exercise trial. In blood, hydrogen peroxide (H2O2), nitric oxide (NO), markers of RO/NS activity 8-isoprostanes and 3-nitrotyrosine, total (GSHt) and oxidised glutathione (GSSG), antioxidant status (APO) and superoxide dismutase (SOD) were determined. There were not observed statistically significant differences in exercise-induced changes in H2O2 and NO concentrations and SOD activity after carnosine intake. However, carnosine prevented an increase in 8-isoprostanes, 3-nitrotyrosine and GSSG concentrations as well as elevated redox status (GSHt-2GSSG)/GSSG at post-exercise period.Although, oral supplementation with 4 g carnosine did not affect RO/NS generation, it significantly attenuated exercise-induced glutathione loss, reduced oxidation/nitration markers concentration and SOD activity. These results suggest that carnosine could provide antioxidative protection for highly trained athletes
The combined effect of cycling cadence and crank resistance on hamstrings and quadriceps muscle activities during cycling
No full textThe effect of cycling cadence and crank resistance on the activity of hamstrings and quadriceps muscles was investigated during cycling movements of able-bodied subjects on a stationary bike with slow and fast speed against different resistance conditions. The ratio of average EMG amplitudes obtained in the two speed conditions (fast/slow) was computed in each resistance condition. This ratio is higher for both muscles if cycling against higher resistance. This shows that in higher resistance condition muscle activities are not only increased but the change of muscle activities with respect to cadence change varied according to resistance condition. Average EMG amplitudes increased at a higher rate with respect to change of cadence when cycling was performed in higher resistance condition. Besides, when cycling faster, hamstrings activity increased generally at a higher rate than that of quadriceps. The correlation between cadence and EMG amplitudes were also investigated. Considering hamstrings, this correlation was low and decreased as resistance increased. The correlation between the time required to drive one cycle and EMG amplitude is negative but in absolute value it is larger than the correlation of cadence and EMG amplitude
Streptozotocin-nicotinamide-induced rat model of type 2 diabetes (review)
No full textDiabetes is one of the five leading causes of death in the world, with type 2 diabetes occurring more frequently than type 1. Management of diabetes without side effects is still a challenge and therefore new strategies need to be examined. Because of difficulties in human research, animal models of diabetes are useful research tools for this purpose and rodent models of type 2 diabetes are the first choice. The aim of this study is an overview on one of the most frequently used models of type 2 diabetes in rat, induced by streptozotocin and nicotinamide, considering its advantages and disadvantages for diabetes research in humans
Relationships between traditional and fundamental dough-testing methods
No full textTwo fundamental test systems were used to evaluate the visco-elastic properties of doughs from wheat samples of three varieties grown at four distinct sites. For comparison, tests were also performed with traditional equipment, namely the Mixograph, an extension tester and a Farinograph-type small-scale recording mixer. Uniaxial dough elongation (with an Instron) produced results similar to the conventional extension tester, except that results were provided in fundamental units (Pascals), the critical value recorded being the elongational stress at maximum strain. Stress relaxation measurements were performed following a small initial shear strain. With this method, it was possible to distinguish between the viscosity and the elastic components of dough visco-elasticity. In all the tests the extra dough-strength properties were evident for the variety (Guardian) that had the 5 + 10 glutenin subunits, in contrast to the other two with the 2 + 12 combination of subunits
Efficient promotion of the sprout growth and rutin production of tartary buckwheat by associated fungal endophytes
No full textThe purpose of this study was to investigate the effects of endophytic fungi from tartary buckwheat on the host sprout growth and functional metabolite production. Without obvious changes in the appearance of the sprouts, the exogenous fungal mycelia elicitors notably stimulated the sprout growth and rutin accumulation, and the stimulation effect was mainly depended on the mycelia elicitor species along with its treatment dose. Three endophytic fungi Fat6 (Bionectria pityrodes), Fat9 (Fusarium oxysporum) and Fat15 (Alternaria sp.) were screened to be the most effective candidates for promoting F. tataricum sprout growth and rutin production. With application of polysaccharide (PS, 150 mg/l) of endophyte Fat6, PS (200 mg/l) of endophyte Fat9, and PS (150 mg/l) of endophyte Fat15, the rutin yield was effectively increased to 47.89 mg/(100 sprouts), 45.85 mg/(100 sprouts) and 46.83 mg/(100 sprouts), respectively. That was about 1.5- to 1.6-fold compared to the control culture of 29.37 mg/(100 sprouts). Furthermore, the present study revealed that the biosynthesis of the functional flavonoid resulted from the stimulation of the phenylpropanoid pathway by mycelia polysaccharide treatments. Application of specific fungal elicitors could be an efficient strategy for improving the nutritional and functional quality of tartary buckwheat sprouts
Isolation and characterization of the complete genome of barley yellow dwarf virus-GAV from wheat in Northwestern China
No full textBarley yellow dwarf virus-GAV (BYDV-GAV) is one of the most serious viruses on wheat in China. In this study, five BYDV-GAV isolates collected from five regions in Northwestern China were sequenced. The complete genome sequences generated in this study along with nine genome sequences of BYDV-GAV isolates available in GeneBank were compared and analyzed. The comparative analysis indicated that the complete genomes of BYDV-GAV showed a low level of genetic diversity with nucleotide sequence identities ranging between 97.0% and 99.7%, and the RNA-dependent RNA polymerase gene (ORF1 + ORF2) was the most variable within the complete genome. Phylogenetic analysis indicated that the BYDV-GAV isolates in Northwestern China could be divided into two groups. In addition, two potential recombination events were detected among the 14 BYDV-GAV isolates. This study provided a detailed description of molecular characterization of BYDV-GAV in Northwestern China based on the complete genome sequences, which increased the understanding of genetic diversity of barley yellow dwarf viruses
Comparative efficiency of functional gene-based markers, start codon targeted polymorphism (SCoT) and conserved DNA-derived polymorphism (CDDP) with ISSR markers for diagnostic fingerprinting in wheat (Triticum aestivum L.)
No full textThree molecular markering techniques: inter-simple sequence repeat (ISSR); start codon targeted (SCoT), conserved DNA-derived polymorphism (CDDP) markers were compared for fingerprinting of 40 varieties of bread wheat. The number of scoreable and polymorphic bands produced using the ISSR, SCoT and CDDP primers for varieties was more than that of genotypes. Average polymorphism information content (PIC) for ISSR, SCoT and CDDP markers was 0.39, 0.41 and 0.34, respectively, and this revealed that three different marker types were equal for the assessment of diversity amongst genotypes. Cluster analysis for three different molecular types revealed that genotypes taken for the analysis can be divided in three and four distinct clusters. There were no significant differences among these markers in terms of the evaluation of genotypes. These results suggest that efficiency of SCoT, CDDP and ISSR markers was relatively the same in fingerprinting of genotypes but SCoT and CDDP analysis are more effective in fingerprinting of wheat genotypes. To our knowledge, this was the first detailed report of a comparison of performance among two targeted DNA region molecular markers (SCoT and CDDP) in comparision with ISSR technique on a set of samples of wheat cultivars. Overall, our results indicate that SCoT, ISSR and CDDP fingerprinting could be used to detect polymorphism for genotypes of wheat
Interactive genotypic influence of triticale and wheat on their crossability and haploid induction under varied agroclimatic regimes
No full textThe investigation was undertaken at two different climatic regimens of NW Himalayas, to determine the response of diverse genotypes of triticale and wheat and environment on their crossability as well as to evaluate the efficiency of Imperata cylindrica-mediated chromosome elimination approach for haploid induction in triticale × wheat (Triticum aestivum) hybrids. The experimental material included three elite hexaploid triticale genotypes (DT123, DT126 and TL9335) and five bread wheat genotypes (DH40, HPW155, HS295, VL829 and C306). Significant genotypic and environmental variations were observed for seed setting at two agroclimatic zones. Among parental genotypes, DT126 (triticale) and C306, HPW155 and HS295 (wheat) responded significantly better for seed setting due to significant positive GCA effects at both locations. Maximum seed set of 39.53% and 45.37% was recorded at short day and long day climates, respectively, proving later as the better location for seed setting in most of the crosses. For all the three parameters of haploid induction, viz. pseudoseed formation, embryo formation and regeneration, significant differences were recorded in all the triticale × wheat hybrids depicting the potential of I. cylindrica-mediated approach for haploid induction. Triticale × wheat cross DT126 × HS295 followed by DT126 × HPW155 were found to be significantly more responsive towards embryo formation and regeneration
Tudomány és irodalom a hellenizmus korában
No full textA kutatást régóta foglalkoztatja a tévesen Aristotelésnek tulajdonított De mundo szerzősége. A cikk amellett érvel, hogy téves kiindulópont az anonim szerzőt valamelyik filozófiai iskolában keresni, mivel a mű csakis egy rétoriskolában jöhetett létre. Nem filozófiai, hanem retorikai mű. A későbbi korokból ismert nézet, miszerint Aristotelés írt ezoterikus és exoterikus műveket, a rétoriskolai hagyomány fényében átértelmezendő: a későbbi hagyományban exoterikus műveknek tartott könyvek a retorikai hagyományban keletkeztek, de az utókor Aristotelésnek tulajdonította őket. Ilyen művek a De mundo, a Secreta secretorum stb.
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Researchers long have been concerned about the authorship of De mundo that was falsely ascribed to Aristotle. The article argues that it was a mistaken starting point to look for the anonymous author in an ancient Greek school of philosophy, because the book should have been written in a school of rhetoric. It is not a philosophical, but rather a rhetoric work. The view which became widespread in later ages that Arsitotle wrote esoteric and exoteric works, needs a reinterpretation in the knowledge of the tradition of schools of rhetoric: the so-called exoteric books should have been written in schools of rhetoric, and they were already attributed in that tradition to Aristotle. These works are the well-known books of Pseudo-Aristotle: De mundo, Secreta secretorum, etc