Role of free radicals in peptic ulcer and gastritis

Background/aims: It has been suggested that the free radicals are closely related with peptic ulcer disease and gastritis. Although many studies have been undertaken to clarify the role of oxygen-derived free radicals, most of them were carried out in animal models. The aim of this study was to assess the reactive oxygen species activity and the damage in Helicobacter pyloriinfected gastric mucosa in humans. Methods: In a total group of 42, there were fifteen cases of peptic ulcer, 14 cases of gastritis and 12 control subjects. Measurement of gastric mucosal malondialdehyde concentrations, which is the end - product of lipid peroxidation, was used to assess oxidative damage to membranes in patients with peptic ulcer and gastritis. Mucosal reduced glutathione glutathione concentrations were also measured in order to study whether reactive oxygen species generation affects levels of the antioxidant peptide, malondialdehyde and glutathione content was then measured in biopsies taken from the gastric antrum. Results: Tissue levels of glutathione were significantly (p <0.001) and malondialdehyde was higher (p<0.001) in patients with peptic ulcer compared to controls. In patients with gastritis, glutathione was also lower (p<0.001) and malondialdehyde higher (p<0.01). Conclusions: Depletion of gastric mucosal glutathione in cases with H.pylori positive peptic ulcer and gastritis may be caused by accumulation of free radicals that can initiate membrane damage by lipid peroxidation

Increased serum malondialdehyde levels in chronic stage of ischemic stroke

Serum lipoperoxidation products such as malondialdehyde (MDA) reflect oxidative stress. There are contradictory results addressing the levels of lipoperoxidation products in chronic phase of ischemic stroke. In the present study, we aimed to determine the serum MDA levels in stroke patients 6 months after the cerebrovascular accident. We also compared serum MDA levels in two major groups of patients with ischemic stroke resulting from small vessel and large vessel diseases, respectively. Serum MDA levels of thirty-eight patients who had ischemic stroke (19 with atherothrombotic ischemic stroke and 19 with lacunar infarction) and 30 healthy volunteers were measured. While there was no significant difference in serum MDA levels between the chronic ischemic stroke subgroups (p = 0.795), the serum MDA levels of patients with atherothrombotic ischemic stroke (p < 0.001) or with lacunar infarction (p < 0.001) were significantly higher compared to the control group. We also demonstrated that serum MDA levels of the patients with and those without hypertension (p = 0.846), diabetes mellitus (p = 0.891), or dyslipidemia (p = 0.38) were not significantly different. In conclusion, serum MDA levels were elevated in chronic stroke patients with small or large vessel diseases. To the best of our knowledge, this is the first report showing that serum MDA levels of these two groups are not sigificantly different. Furthermore, serum MDA levels do not differ solely by the existence or nonexistence of hypertension, diabetes mellitus or hyperlipidemia. © 2006 Tohoku University Medical Press

Energy saving by using an axial flow deep well pump: An application in the net frames in Lake Karacaören -2

Turkey is home to a large number of lakes, dam lakes and small lakes which have a great potential for growing fishery products. Growing trout in net frame systems manufactured in dam lakes is very common and economically very promising application. For growing trout, certain conditions such as certain water temperature range and minimum dissolved oxygen (DO) level must be satisfied. The water temperature required should be at 17-20 °C to grow trout. Also, the amount of dissolved oxygen (DO) should never fall below 6-7 mg/L. As the temperature rises during the months of June-September, water temperature rises above the acceptable limits to grow trout. Producers usually use different types of internal combustion engine-pump (ICE-P) systems to provide the circulation of the colder water in the deeper parts of the lake to lake surface to grow trout in these months. But, this method is not economically feasible. In this study, as an alternative to ICE-P system, an axial flow deep well pump has been proposed for energy saving purposes. To validate the feasibility of the system, total of 40 net frame systems each has dimensions of 5×5×8 meters have been installed to grow trout in net frames in Lake Karacaören 2 in Burdur, Turkey. To grow trout in the hot seasons, it is necessary to circulate the colder water in the deeper parts of the lake to lake surface economically. For this aim, total of 10 an axial flow deep well pumps (AFDWPs) having a capacity of 300 m3/h, head of 4 m and running at 2850 rpm which is driven by 5.5 kW deep well motor (DWM) have been specially designed and manufactured. To compare the classical water circulation method with ICE-P and newly proposed AFDWP, after every two pumps (ICE/AFDWP) are installed, mean water temperatures were measured along the water column in net frame with the depth of 8 meters and also energy consumptions have been compared during the months of June to September. AFDWP and ICE-P were used only in these months where the water has to be circulated. According to the results energy consumption by using AFDWP was about 90 MWh/year, on the other hand, energy consumed by ICE-P was about 1949 MWh/year during the months of June-September. As a result, significant energy saving of 95.3 % (1906.8 MWh/year) can be obtained by using proposed AFDWP instead of the classical ICE-P during these months for total of 40 net frames. © 2012 TIBTD Printed in Turkey

Right lung agenesis and left lung bronchiectasis

A 30-year-old man was diagnosed to have right lung agenesis and left pulmonary bronchiectasis after diagnostic workup for dyspnea developed during hemodialysis due to CRF. We report this patient as case report because he had a longer survival and no associated systemic malformation though right-sided lung agenesis contrary to data in the literature. © 2005 Elsevier Ltd. All rights reserved

Prevalence and risk factors for methicillin-resistant Staphylococcus aureus colonization among outpatients undergoing hemodialysis treatment

Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) is frequent among hemodialysis patients and lead to increased morbidity and mortality rates. It is known that nasal colonization plays an important role for the development of MRSA infections. The aim of this study was to determine the prevalence and risk factors for MRSA colonization among outpatients undergoing hemodialysis. A total of 466 adult patients (199 female, 267 male; age range: 18-89 years, mean age: 55.8 ± 15.1 years) who were under hemodialysis between September-December 2008 in different health centers at Pamukkale/ Denizli region, Turkey, were included in the study. Swab samples obtained from anterior nares of patients were cultivated on sheep-blood agar and mannitol-salt agar media. The isolates were identified by conventional bacteriological methods. S.aureus strains were isolated from 204 (43.8%) patients and 34 (16.7%) were found methicillin-resistant. Thus the rate of MRSA colonization in hemodialysis patients was detected as 7.3% (34/466). All of the MRSA strains'were found susceptible to vancomycin, linezolid and tigecycline, while the resistance rates for the other antimicrobial agents were as follows: 70.6% to azithromycin and claritromycin; 64.7% to erythromycin; %58.8 to clindamycin, gentamicin and trimethoprim-sulfamethoxazole; 55.9% to ciprofloxacin; 44.1% to tetracycline and rifampin; 5.9% to chloramphenicol. Inducible clindamycin resistance in MRSA isolates was %23.5 (8/34), and multidrug resistance rate was 76.5% (26/34). Multivariate analysis revealed that the history of previous hospitalization within a year [odds ratio (OR), 3.426; 95% confidence interval (CI), 1.595-7.361, p= 0.002] and the presence of chronic obstructive lung disease (OR, 5.181; 95% CI, 1.612-16.648, p= 0.006) were independent risk factors for MRSA colonization in this population. A better understanding of the prevalence and risk factors for nasal MRSA colonization among hemodialysis population may hold significant implications for both the treatment strategies and prevention of MRSA infections to establish appropriate infection control measures

Experimental investigation of cooling with multiple air jets on auto glass tempering

Impinging air jets due to their high heat and mass transfer capacity are widely used for heating, cooling and drying applications in nowadays industry. This study aims to investigate auto glass tempering project. Heat transfer characteristics of heated glass plates during their cooling with mutually placed circular air jets have been experimentally investigated. 4 mm thick glass samples were used in the experiments. Cooling process has been performed with 16 mutually placed nozzles of 8 mm in diameter and 80 mm in length in staggered arrangement. Nozzles were made of seamless aluminum pipes. Experiments have been conducted for dimensionless jet to plate distances (H/D) between 1 and 10, and S/D ratios which represents dimensionless distance between nozzle axis, for 2≤S/D≤10. Reynolds number has been fixed at 30000 for all experiments. According to the results the highest average Nusselt number (Num) has been achieved for S/D=2 and H/D=4 with a value 123.3 and the lowest average Nusselt number was obtained for S/D=10 and H/D=10 with a value 58.6