Protective effects of intraperitoneal vitamin C, aprotinin and melatonin administration on retinal edema during experimental uveitis in the guinea pig

A considerable amount of clinical and experimental evidence exists suggesting the involvement of reactive oxygen substances (ROS) in the aetiology of uveitis. The activated phagocytic system of polymorphonuclear leucocytes in uveitis is involved in the generation of ROS. In addition to their direct free radical scavenging action, aprotinin, melatonin and vitamin C are known to protect against oedema formation and can preserve plasma membrane fluidity and free radical production. Histological changes in the retina that occur during uveitis are not well explained. The purpose of this study was to determine whether vitamin C, aprotinin and melatonin can protect the retina from damage accompanying experimental uveitis (EU). Thirty adult male guinea pigs were divided into five groups of six animals each. The first group was used as control. The right eyes of groups 2, 3, 4 and 5 received an intravitreal injection of bovine serum albumin for induction of experimental uveitis. At the same time and also on the consecutive third day, groups 3, 4 and 5 received intraperitoneal injections of vitamin C (ascorbic acid, 100 mg kg(-1) body wt), aprotinin (20,000 kIU kg(-1) body wt) and melatonin (10 mg kg(-1) body wt), respectively. The animals were killed on the sixth day. The average thickness of the retina and inner plexiform layer for each eye was measured in sagittal section near the optic nerve and expressed in microns. The thickness of the retina and inner plexiform layer in the control group was significantly (p < 0.01) lower than in the group EU as compared with the group EU plus vitamin C, group EU plus aprotinin, group EU plus melatonin (p < 0.05). The thicknesses of the retina and inner plexiform layer in group EU plus vitamin C, group EU plus aprotinin and group EU plus melatonin were significantly (p < 0.01) lower than that in the group EU. The difference in thickness of the retina and inner plexiform layer among the groups 3, 4 and 5 was not significant (p > 0.05). In conclusion, this study demonstrated that oedematous effects of EU on the retina were reduced by the administration of intraperitoneal vitamin C, aprotinin and melatonin, i.e. these antioxidants had significant protective effects on the retina of guinea pigs against oedematous damage in EU. However, the reductive effect of vitamin C on EU was greater than that of aprotinin and melatonin. The intraperitoneal vitamin C, aprotinin and melatonin supplementations may strengthen the antioxidant defence system because of decreased ROS, and these agents may play a role in treating uveitis.     

Helicobacter pylori infection in Turkish children: comparison of diagnostic tests, evaluation of eradication rate, and changes in symptoms after eradication

BACKGROUND: Helicobacter pylori infection is most frequently acquired in childhood. After this organism is eradicated, the rate of reinfection is low. Thus, it is very important to diagnose and treat the disease appropriately in childhood, and to be able to assess eradication with certainty. Eradication of H. pylori infection is reported to reduce or eliminate abdominal pain and dyspeptic symptoms in children. PATIENTS AND METHODS: The study involved 102 children who had already been diagnosed with symptomatic H. pylori infection based on gastric histopathological examination, urea breath test, rapid urease test, serology and culture. Each patient's symptoms and family history of gastrointestinal problems were recorded. Using histology as the gold standard for identifying H. pylori infection, we determined the diagnostic sensitivity of each of the other methods. Omeprazole or lansoprazole, amoxicillin and clarithromycin were administered as eradication treatment, and each patient was re-evaluated by urea breath test 8 weeks later. Each child was re-interviewed about symptoms after treatment. These answers and the results of drug sensitivity testing were recorded. Cases of failed eradication were re-treated with a quadruple-drug regimen of tetracycline, metronidazole, bismuth subsalicylate and omeprazole. RESULTS: The most frequent symptom was abdominal pain (89.2%). Fifty-four per cent of the subjects had a family history of dyspeptic symptoms. Sixty-six patients (64.7%) exhibited nodularity in the antral mucosa. The sensitivities of the diagnostic tests in histologically proven cases were as follows: urea breath test 100%, rapid urease test 89.2%, serology 71.9%, and culture 54.9%. Metronidazole had the highest frequency of resistance (36.4%) and the rate of clarithromycin resistance was 18.2%. The eradication rate after first-line therapy was 75.5%, and abdominal pain and dyspeptic symptoms were reduced or completely resolved in 75.7% of the successful-eradication cases. The proportion of failed-eradication cases that responded well to quadruple-drug therapy was 93.8%. CONCLUSION: Symptomatic H. pylori infection in a child should always be treated. The urea breath test is an accurate and reliable way to identify H. pylori-positive patients and to determine the response to treatment. Triple-agent therapy is effective for eradicating H. pylori infection in children and usually helps reduce or eliminate dyspeptic symptoms. The level of H. pylori resistance to metronidazole is high in our region. The significant rate of resistance to clarithromycin (18.1%) may explain the treatment failure observed in this study.     

Docosahexaenoic acid provides protective mechanism in bilaterally MPTP-lesioned rat model of Parkinson's disease

Docosahexaenoic acid (DHA), a major polyunsaturated fatty acid (PUFA) in the phospholipid fraction of the brain, is essential for normal cellular function. Neurodegenerative disorders such as Parkinson's disease (PD) often exhibit significant declines in PUFAs. The aim of this study was to observe the effects of DHA supplementation in an experimental rat model of PD created with '1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine' (MPTP). Adult male Wistar rats were divided into four groups: (1) Control; (2) DHA-treated; (3) MPTP-induced; and (4) MPTP-induced + DHA-treated. Motor activity was investigated using the 'vertical pole' and 'vertical wire' tests. The dopaminergic lesion was determined by immunohistochemical analysis for tyrosine hydroxylase (TH)-immunopositive cells in substantia nigra (SN). Immunoreactivities of Bcl-2, Akt and phosphorylated-Akt (p-Akt) in SN were evaluated by immunohistochemistry. MPTP-induced animals exhibited decreased locomotor activity, motor coordination and loss of equilibrium. Diminished Parkinsonism symptoms and decreased dopaminergic neuron death were detected in the MPTP-induced + DHA-treated group compared to the MPTP-induced group. Moderate decreases in Akt staining were found in the MPTP-induced and MPTP-induced + DHA-treated groups compared to controls. p-Akt immunoreactivity decreased dramatically in the MPTP-induced group compared to the control; however, it was increased in the MPTP-induced + DHA-treated group compared to the MPTP-induced group. The staining intensity for Bcl-2 decreased prominently in the MPTP-induced group compared to the control, while it was stronger in the MPTP-induced + DHA-treated group compared to the MPTP-induced group. In conclusion, DHA significantly protects dopaminergic neurons against cell death in an experimental PD model. Akt/p-Akt and Bcl-2 pathways are related to this protective effect of DHA in experimental PD.     

Evaluation of seasonal antioxidant activity and total phenolic compounds in stems and leaves of some almond (Prunus amygdalus L.) varieties

Background

This study aimed to determine the seasonal changes of total antioxidant activity and phenolic compounds in samples taken from leaves (April, July, October) and stems (April, July, October, January) of some almond (Prunus amygdalus L.) varieties (Nonpareil, Ferragnes and Texas).

Results

It was indicated that antioxidant activity and phenolic compounds in leaves and stems of Nonpareil, Ferragnes and Texas showed seasonal differences. Antioxidant activity IC₅₀ of these varieties reached the highest value in April for leaves whereas in October for stems. The highest level of total phenolic compounds was in January for stems while in October for leaves.

Conclusions

These results showed that total antioxidant activity and phenolics in leaves and stems of almond varieties changed according to season and plant organ.     

The effects of docosahexaenoic acid on glial derived neurotrophic factor and neurturin in bilateral rat model of Parkinson's disease

Parkinson's disease (PD) is the second most common neurodegenerative disorder marked by cell death in the Substantia nigra (SN). Docosahexaenoic acid (DHA) is the major polyunsaturated fatty acid (PUFA) in the phospholipid fraction of the brain and is required for normal cellular function. Glial cell line derived neurotrophic factor (GDNF) and neurturin (NTN) are very potent trophic factors for PD. The aim of the study was to evaluate the neuroprotective effects of GDNF and NTN by investigating their immunostaining levels after administration of DHA in a model of PD. For this reason we hypothesized that DHA administration of PD might alter GDNF, NTN expression in SN. MPTP neurotoxin that induces dopaminergic neurodegeneration was used to create the experimental Parkinsonism model. Rats were divided into; control, DHA-treated (DHA), MPTP-induced (MPTP), MPTP-induced+DHA-treated (MPTP+DHA) groups. Dopaminergic neuron numbers were clearly decreased in MPTP, but showed an increase in MPTP+DHA group. As a result of this, DHA administration protected dopaminergic neurons as shown by tyrosine hydroxylase immunohistochemistry. In the MPTP+DHA group, GDNF, NTN immunoreactions in dopaminergic neurons were higher than that of the MPTP group. In conclusion, the characterization of GDNF and NTN will certainly help elucidate the mechanism of DHA action, and lead to better strategies for the use of DHA to treat neurodegenerative diseases.     

Effects of Exogenous Indole Butyric Acid and Callus Formation on the Anti-oxidant Activity, Total Phenolic, and Anthocyanin Constituents of Mulberry Cuttings

In order to evaluate the effects of exogenous indole butyric acid （IBA） and callus formation on the antioxidant activity, total phenolics, and anthocyanin constituents of Morus nigra L. and M. alba L. cuttings, we investigated the variations before and after the treatment. The results indicate that anti-oxidant ability, total phenolic, and anthocyanin constituents of the callus stems of both Morus species were higher than those of non-callus forming species. There were also increases observed in anti-oxidant ability, total phenolic, and anthocyanin constituents of calli treated with IBA （1 000-3 000 mg/L）.     

Visual arts education provisions for primary schools in Turkey

This article examines the history of art education in Turkey. Since the beginning, the purposes of the arts and art education have been a point of discussion by various authorities. Whether art education should be taught, and how it needs to be taught, have been at the forefront of educationalists' minds. As a result, introducing certain models of art education has been a challenge. The objective of this article is to present the changes in art education since the 19th century in Turkey. The main focus is on art education practices and policies and an overview of key events in Turkey's history of art education. The article also presents issues related to the importance of visual arts education in Turkish primary school settings. In so doing, this research aims to show readers how past developments helped to create the current visual art education policy in Turkey.     

Synthesis and molecular docking study of some 5,6-dichloro-2-cyclopropyl-1H-benzimidazole derivatives bearing triazole,oxadiazole, and imine functionalities as potent inhibitors of urease

A new series of benzimidazole compounds including hydrazinecarbothioamide, 1,2,4-triazole, 1,3,4-oxadiazole and imine function were synthesized starting from 5,6-dichloro-2-cyclopropyl-1H-benzimidazole. All of the benzimidazole derivatives exhibited good urease inhibitor activity. Compound 6a proved to be the most potent showing an enzyme inhibitory activity with an IC₅₀ = 0.06 µM. Molecular docking studies were also conducted on enzyme extracted from Jack bean urease to identify the binding mode of the newly synthesized compounds.     

Changes in zinc levels and superoxide dismutase activities in the skin of acute, ultraviolet-B-irradiated mice after treatment with ginkgo biloba extract

Acute ultraviolet-B (UV-B) irradiation is known to act as an initiator in the formation of reactive oxygen species. These oxygen products are highly reactive and they are able to cause irreversible damage to cellular components. Oxygen free radicals are normally neutralized by very efficient systems in the body. These include antioxidant enzymes like superoxide dismutase (SOD). In a healthy subject, there is a balance between free radicals and the levels of antioxidants. In some pathological conditions such as oxidative stress, the level of antioxidants is significantly reduced. The skin contains relatively high levels of zinc (Zn), an essential element known to be a cofactor in some metabolic pathways. Zinc has also been reported to have antioxidant properties. In the present study, we investigated the effect of ginkgo biloba extract (Gbe), a potent free-radical scavenger, on UV-B-irradiated skin by measuring SOD activity and Zn levels in the skin, before and after treatment. The SOD activity was decreased after UV-B exposure, in comparison with the control group (p<0.05). After Gbe treatment, the SOD activity increased (p<0.05) as compared with the untreated UV-B irradiated group. The Zn levels changed in the same pattern as the SOD activity values.     

Streptomyces boncukensis sp. nov., isolated from saltern soil

Archives of Microbiology - A novel Gram-stain positive, aerobic, non-motile Actinobacterium, designated strain SB3404T, was isolated from saltern soil collected from Boncuk Saltern,...