The relationship between antioxidant enzymes and lipid peroxidation in senescent rat erythrocytes.

The aim of this study was to gain more complete information about the relationships between some endogenous antioxidants and the malondialdehyde (MDA) as a marker of lipid peroxidation, during D-galactose induced senescence. The activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and the concentrations of uric acid (UA) in plasma and MDA in erythrocyte's hemolysate, were determined in 15 D-galactose (D-gal), treated rats and compared with 15 placebo. The activity of the erythrocyte's CAT was found significantly increased due to the senescence. The ratio of the activities of antioxidant enzymes R=SOD/(GPx+CAT) was significantly decreased due to the senescence and negatively correlated with the MDA (rho=-0.524, p=0.045). The antioxidant enzymes SOD and GPx negatively correlated with the MDA, while CAT displayed no correlation. Further, the UA positively correlated with the ratio of activities of the antioxidant enzymes R=SOD/(GPx+CAT), (rho=0.564, p=0.029 for senescent rats). Obtained results may contribute to better understanding of the process of D-gal induced senescence in the erythrocytes.

NonHodgkin's Lymphoma with Peritoneal Localization.

The gastrointestinal tract is the most common extranodal site involved with lymphoma accounting for 5-20% of all cases. Lymphoma can occur at any site of the body, but diffuse and extensive involvement of the peritoneal cavity is unusual and rare. We report a case of diffuse large B-cell lymphoma in a 57-year-old female infiltrating the peritoneum and omentum and presenting with ascites and pleural effusion. The performed examinations did not discover any pathological findings affecting the digestive tract or parenchymal organs, except for diffuse thickening of the peritoneum and omentum. Peripheral, mediastinal, or retroperitoneal lymphadenopathy was not registered. The blood count revealed only elevated leukocytes and on examination there were no immature blood cells in the peripheral blood. The cytology from the ascites and pleural effusion did not detect any malignant cells. Due to the rapid disease progression the patient died after twenty-two days of admission. The diagnosis was discovered postmortem with the histological examination and immunohistochemical study of the material taken during the surgical laparoscopy performed four days before the lethal outcome. Although cytology is diagnostic in most cases, laparoscopy with peritoneal biopsy is the only procedure which can establish the definitive diagnosis of peritoneal lymphomatosis.

Age and heat exposure-dependent changes in antioxidant enzymes activities in rat's liver and brain mitochondria: role of alpha-tocopherol.

To investigate the role of mitochondrial antioxidant capacity during increased susceptibility to heat accompanied by the aging, young and aged Wistar rats were exposed on heat for 60 min. After heat exposure, hepatic and brain mitochondria were isolated. Our results revealed changes in antioxidant enzyme activities in liver and brain mitochondria from young and to a greater extent in aged rats. Our measurements of MnSOD, GPx and GR activity indicate greater reactive oxygen species production from the mitochondria of aged heat exposed in comparison to young heat exposed rats. Also in the aged rats, the effect of alpha-tocopherol treatment in the prevention of oxidative stress occurred as a result of heat exposure, is less pronounced. Taken together, our data suggest that mitochondria in aged rats are more vulnerable and less able to prevent oxidative changes that occur in response to acute heat exposure.

Improvement of cerebral oxygenation during laparoscopy using intermittent sequential compression of legs.

The creation of CO2 pneumoperitoneum during laparoscopy causes a series of adverse effects. Impairment of brain oxygen saturation during laparoscopy is a result of increased intra-abdominal pressure, absorbed CO2 and increased intracranial pressure. The aim of this study is to investigate the possible effects of pneumatic inter-mittent sequential compression (ISC) of legs on oxygenation of the brain during laparoscopy. 100 patients, ASA groups 1 and 2, subjected to elective laparoscopic cholecystectomy, were included in this study. The patients were divided into two groups consisting of 50 patients each, group I, control group, and group II, where ISC was applied. Oxygen saturation of the mixed venous blood from the internal jugular vein (SjvO2) is an indirect assessment of cerebral oxygen use (oxygenation of the brain). Blood samples were obtained from the bulb of the right jugular vein, as the dominant side for venous drainage from the brain. Informed consent was obtained from each patient. Blood samples of 2 ml were obtained several times during the operation; the first sample immediately after anesthesia induction in order to establish the baseline values of SjvO2, the second sample immediately after the creation of the pneumoperitoneum, and then every 15 minutes respectively until the end of the pneumoperitoneum. The last sample was obtained before the extubation of the patients. The ISC in group II was terminated after obtaining the last blood sample. Results showed that the average values of oxygen saturation of the mixed venous blood from the internal jugular vein--SjvO2 levels were higher in group II where ISC was applied (82.3%→86.4%→85.3%→80.2%→82.8%→80.4%), compared to group I, without ISC (85.5%→77.8%→80.6%→83.8%→84.8%), statistically significant in the second and third measurement for p<0.05 for the second and the third measurement, i.e. after the creation of pneumoperitoneum, when the decreease in the brain oxygenation is most dramatic in the group without ISC. In conclusion, application of intermittent sequential compression of the legs is a simple and safe technique for preserving the brain oxygenation during laparoscopy by restoring the blood return from the legs.

Expression of c-KIT oncoprotein in gastrointestinal stromal tumors in adults and children: guideline for diagnosis and treatment.

Gastrointestinal stromal tumors (GISTs) represent a distinct oncogenetic entity that is now center stage in clinical trials of kinase-targeted therapies. These neoplasms express the c-KIT oncoprotein and occur predominantly in adults, more rarely in children. Two selected cases of GIST expressing c-KIT, including one adult patient and a 9-year-old boy are presented. The adult patient was admitted for palpable abdominal mass without other clinical symptoms. On biopsies obtained by scanner-guided procedure, diagnosis of ganglioneurinoma was proposed with the remark that GIST tumor could not be categorically excluded. At surgery, voluminous encapsulated tumor located at the jejunal wall was found and totally excised. The second patient presented with acute upper gastrointestinal hemorrhage associated with several months history of general fatigue and loss of appetite. Computed tomography (CT) and magnetic resonance imaging (MRI) showed a tumoral mass arising from the lesser curvature of the stomach compatible with GIST. Two small metastatic lesions in the liver were also detected. Combined treatment by surgery and systemic therapy by the tyrosine kinase inhibitor imatinib mesylate was applied.