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951.
The present study aimed at detecting DNA damage and fragmentation as well as histone acetylation depending on oxidative stress caused by CCl4 intoxication. Also, the protective role of N-acetyl cysteine, a precursor for GSH, in DNA damage is investigated. Sixty rats were used in this study. In order to induce liver toxicity, CCl4 in was dissolved in olive oil (1/1) and injected intraperitoneally as a single dose (2 ml/kg). N-acetyl cysteine application (intraperitoneal, 50 mg/kg/day) was started 3 days prior to CCl4 injection and continued during the experimental period. Control groups were given olive oil and N-acetyl cysteine. After 6 and 72 h of CCl4 injection, blood and liver tissue were taken under ether anesthesia. Nuclear extracts were prepared from liver. Changes in serum AST and ALT activities as well as MDA, TAS, and TOS levels showed that CCl4 caused lipid peroxidation and liver damage. However, lipid peroxidation and liver damage were reduced in the N-acetyl cysteine group. Increased levels in 8-hydroxy-2-deoxy guanosine and histone acetyltransferase activities, decreased histone deacetylase activities, and DNA breakage detected in nuclear extracts showed that CCl4 intoxication induces oxidative stress and apoptosis in rat liver. The results of the present study indicate that N-acetyl cysteine has a protective effect on CCl4-induced DNA damage. 相似文献
952.
This study was carried out to assess the localization of hyaluronic acid (HA) and the distribution of glycoproteins in the gastrointestinal system of adult Hyla orientalis. Histochemical analysis of the gastrointestinal system in H. orientalis showed that mucous content included glycogene and/or oxidable dioles [periodic acid/Schiff (PAS)+], neutral or acid-rich (PAS/AB pH 2.5+), sialic acid residues (KOH/PAS+) and acid sulphate [Aldehyde fuchsin (AF)+] glycoproteins. However the mucus content was not the same in stomach, small and large intestine. The mucus content of stomach included only glycogene and/or oxidable dioles and sialic acid residues. Besides these histochemical methods, the localization of HA was detected using biotinylated hyaluronic acid binding protein labeled with streptavidin-fluorescein isothiocyanate (FITC). In the extracellular matrix of the submucosa, the reaction for HA was evident. Since HA was located in submucosa beneath the epithelial layer of gastrointestinal system, it has a significant role in hydric balance, and essential to provide the gastrointestinal system integrity and functionality. According to biometric results, there were statistical differences between small and large intestine in terms of the amount of material stained positive with PAS/AB, PAS, KOH/PAS and AF/AB. Additionally, number of goblet cells in the small and large intestine was significantly different.Key words: Gastrointestinal system, goblet cell, glycoproteins, hyaluronic acid, amphibian, Hyla. 相似文献
953.
Jere Kahanp?? 《ZooKeys》2014,(441):291-303
A checklist of the Agromyzidae (Diptera) recorded from Finland is presented. 279 (or 280) species are currently known from the country. Phytomyza
linguae Lundqvist, 1947 is recorded as new to Finland. 相似文献
954.
Jere Kahanp?? 《ZooKeys》2014,(441):305-309
A checklist of 29 species in the smaller carnoid families Acartophthalmidae, Canacidae, Carnidae and Milichiidae (Diptera) recorded from Finland is presented. Tethinidae are also included as a subfamily of Canacidae. Phyllomyza
tetragona Hendel is removed from the list as no reliable records of this species within the post-1944 borders of Finland could be found. 相似文献
955.
Jere Kahanp?? 《ZooKeys》2014,(441):319-324
A Finnish checklist of the sphaeroceroid fly families Chyromyidae and Heleomyzidae is provided. 相似文献
956.
957.
958.
Maria Bokarewa Mikael Brink Malin Erlandsson Solbritt Rantap?? Dahlqvist 《Arthritis research & therapy》2014,16(1):R45
Introduction
Antibodies against citrullinated peptides (anti-CCP) and increased levels of cytokines precede the development of rheumatoid arthritis (RA) by several years. Recently, the proteins survivin and Fms-like tyrosine kinase 3 ligand (Flt3L) have been identified as biomarkers of RA associated with joint destruction. Our objective was to investigate the potential of survivin and Flt3L as predictors of RA in samples from patients prior to onset of symptoms.Methods
This study included 47 individuals sampled before onset of RA (median 2.5 years (IQR 4.5) and 155 matched controls, all were donors to the Medical Biobank of Northern Sweden, and 36 RA patients. Levels of anti-CCP, survivin and Flt3L were measured using ELISAs and 29 cytokines/chemokines by multiplex detection.Results
Levels of survivin were increased in pre-symptomatic individuals compared with controls (P = 0.003), whilst the levels of Flt3L were similar. The frequency of survivin positivity in the pre-symptomatic individuals was increased compared with the controls (36.2 vs.14.2%, P = 0.001) and predicted disease development (odds ratio (OR) =3.4 (95% confidence interval (CI) 1.6-7.2)). The frequency of survivin and Flt3L in RA patients was increased compared with the controls (both, P <0.0001, OR = 12.1 (95% CI, 5.3-27.6) and OR = 11.0 (95% CI, 3.9-30.9), respectively). Anti-CCP positive pre-symptomatic individuals and patients had significantly higher levels of survivin compared with anti-CCP2 negative individuals. In pre-symptomatic individuals, survivin correlated with IL-12, IL-1β and IL-9 whereas Flt3L correlated to a significantly broader spectrum of cytokines in RA patients.Conclusion
Proto-oncogene survivin was increased in individuals prior to onset of symptoms of RA and was correlated to cytokines suggesting its role at pre-clinical stages of the disease. 相似文献959.
960.
Snake venoms are cocktails comprising combinations of different proteins, peptides, enzymes and toxins. Snake toxins have
diverse characteristics having different molecular configuration, structure and mode of action. Many toxins derived from snake
venom have distinct pharmacological activities. Venom from Bungarus fasciatus (commonly known as banded krait) is a species of
elapid snake found on the South East Asia and Indian sub-continent, mainly contains neurotoxins. Beta bungartotoxin is the major
fraction of Bungarus venom and particularly act pre-synaptically by obstructing neurotransmitter release. This toxin in other
snake species functionally forms a heterodimer containing two different subunits (A and B). Dimerization of these two chains is a
pre-requisite for the proper functionality of this protein. However, B. fasciatus bungartotoxin contains only B chain and their
structural orientation in yet to be resolved. Therefore, it is of interest to describe the predicted structure model of the toxin for
functional insights. In this work we analyzed the neurotoxic nature, their alignments, secondary and three dimensional structures,
functions, active sites and stability with the help of different bioinformatical tools. A comprehensive analysis of the predicted model
provides approaching to the functional interpretation of its molecular action. 相似文献