Reorganization of language-related neuronal networks in patients with left temporal lobe epilepsy - an fMRI study.

To investigate the inter- and intrahemispheric reorganization of the language cortex in left temporal lobe epilepsy (TLE) with left-sided hippocampal sclerosis. A functional magnetic resonance imaging was performed on 13 right-handed patients suffering from medically intractable left TLE, and in 13 sex- and age-matched healthy controls. The activation paradigm used was a silent word generation task. A language laterality index (LI) was calculated from the number of activated voxels in the right and left anterior two-thirds of the hemispheres. Significant differences between the patients and the controls were observed in the activation of the left-sided inferior frontal gyrus. Less consistent findings in this region, as well as the relative protection of Broca's area from the activation, were revealed in the patients. In addition, different patterns of activation were proven in the cerebellum and other cortical as well as subcortical brain structures within both hemispheres. Significant differences were also found in the values of the language LIs between the investigated groups: these values suggested a more bihemispheric language representation in the patients. As anticipated, lateralization of the language functions in the epileptics significantly decreased in connection with an earlier age of initial insult. Our results support the hypothesis of a significant intra- and interhemispheric functional reorganization of language-related neuronal networks in left TLE.

Amplification and overexpression of HER-2/neu in invasive ductal carcinomas of the pancreas and pancreatic intraepithelial neoplasms and the relationship to the expression of p21(WAF1/CIP1).

Overexpression of HER-2/neu was described in pancreatic intraepithelial neoplasia (PanIN) and in invasive ductal adenocarcinoma of pancreas in a variable proportion of cases. The effects of HER-2/neu overexpression on mitogenic signalling and cell cycle progression were studied in breast luminal epithelial cells and mitogen activated protein kinase-dependent induction of p21(WAF1/CIP1) was found to be necessary for G1 phase progression. Overexpression of p21(WAF1/CIP1) was described as an early event in the development of PanIN by Biankin et al. (2001) and this finding was supported by our previous study that, moreover, did not confirm the possible role of activating K-ras mutations in the induction of p21(WAF1/CIP1) overexpression. Relationship between p21(WAF1/CIP1) expression and HER-2/neu status in PanIN lesions and ductal adenocarcinoma of the pancreas was investigated in our study. Expression levels of p21(WAF1/CIP1) and HER-2/neu were examined imunohistochemically and the amplification of HER-2/neu gene was evaluated by fluorescence in situ hybridisation in HER-2/neu overexpressing adenocarcinomas. Fourty nine pancreatic resection specimens from patients with invasive adenocarcinoma were included into the study. A large spectrum of PanIN lesions adjacent to the structures of infiltrating adenocarcinoma was also examined. The possible role of HER-2/neu in an induction of p21(WAF1/CIP1) overexpression was not confirmed and p21(WAF1/CIP1) overexpression seems to be HER-2/neu independent in pancreatic ductal adenocarcinoma according to our results. Increasing levels of HER-2/neu expression were demonstrated in pancreatic intraepithelial neoplasia and in 18.75% of pancreatic adenocarcinoma. The only 2 from 9 HER-2/neu overexpressing adenocarcinomas showed the amplification of HER-2/neu gene. Based on these results, the overexpression of HER-2/neu in pancreatic adenocarcinoma seems to be a result of increased transcription rather than gene amplification. Therefore HER-2/neu represents a good target for therapy of pancreatic adenocarcinoma only in isolated cases.

[Apoptosis and expression of bcl-2 protein in invasive ductal adenocarcinoma of the pancreas]. / Apoptóza a exprese bcl-2 proteinu u invazivního duktálního adenokarcinomu pankreatu.

Apoptosis plays a central role in the development and/or progression of cancer. There are several methods for detection of apoptotic cells in tissue sections including light and electron microscopy, in situ nick end-labeling (ISEL), TdT-mediated dUTP nick-end labeling (TUNEL) and immunohistochemical detection of proteins associated with apoptosis. Apoptosis was assessed by the monoclonal antibody M30 CytoDEATH (M30), which is specific for neo-epitope in cytokeratin 18 that becomes available at an early caspase cleavage during apoptosis. Expression of bcl-2 protein was evaluated, because bcl-2 protein plays an important role in the regulation of apoptosis. Twenty-six invasive ductal adenocarcinomas of the pancreas were studied immunohistochemically with antibodies M30 and bcl-2. The mean apoptotic index (AI, the percentage of apoptotic cells of the total tumor cells number) was 2.75%. High AI (> 10%) was observed in 4 cases of the 26 pancreatic carcinomas (15%). Protein bcl-2 was expressed in 3 cases (11.5%). The AI did not correlate with the expression of protein bcl-2. In conclusion, the detection of neo-epitope in cytokeratin 18 by monoclonal antibody M30 can be used for quantification of apoptotic cells with immunohistochemical techniques in tissue sections. It is a new approach to evaluate apoptosis in pancreatic carcinomas. The low positivity of bcl-2 expression in pancreatic adenocarcinomas suggests that bcl-2 protein does not play a central role in pancreatic tumorigenesis and cancer progression.

Relationship between K-ras mutation and the expression of p21WAF1/CIP1 and p53 in chronic pancreatitis and pancreatic adenocarcinoma.

Overexpression of p21WAF1/CIP1 was recently described as an early event in the development of pancreatic intraepithelial neoplasia. Since activating K-ras mutations are described in more than 80% of pancreatic cancers and are known to increase intracellular levels of p21WAF1/CIP1 in experimental models, the possible role of activating K-ras mutations in an induction of the p21WAF1/CIP1 expression was investigated in our study. We examined 71 surgical specimens, 29 of chronic pancreatitis and 42 of invasive ductal adenocarcinoma both having a large spectrum of PanIN (pancreatic intraepithelial neoplasia) lesions. Expression of p53 and p21WAF1/CIP1 was examined immunohistochemically and codon 12 K-ras mutational analysis was performed using the very sensitive mutant-enriched PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) analysis. Our study demonstrated the overexpression of p21WAF1/CIP1 as an early event in the development of pancreatic intraepithelial neoplasia in the group of chronic pancreatitis and invasive adenocarcinoma as well. Overexpression of p21WAF1/CIP1 increased progressively from normal ducts through the spectrum of PanIN lesions to invasive carcinomas. The p53 overexpression increased again progressively according to the severity of the lesion and seems to be a later event in the development of pancreatic intraepithelial neoplasia if compared to p21WAF1/CIP1 expression. Our results confirmed also the possible p53 independent p21WAF1/CIP1 expression in some PanIN2, PanIN3 lesions and invasive carcinomas. K-ras mutations were not revealed in samples with only low grade PanIN lesions (PanIN1a and PanIN1b). K-ras mutations were detected in 69,4% adenocarcinomas and in only one case of chronic pancreatitis. Two codon 12 K-ras positive pancreatic carcinomas showed K-ras mutations in the surrounding normal pancreatic tissue. In adenocarcinomas, no statistically significant correlation was found between K-ras mutational status and p21WAF1/CIP1 and p53 expression, respectively. The possible role of activating K-ras mutations in an induction of p21WAF1/CIP1 expression was not confirmed in this study.

[Molecular diagnosis in pancreatic carcinoma]. / Príspevek k molekulární diagnostice pankreatického karcinomu.

Present diagnostic possibilities virtually do not make it possible to diagnose early stages of pancreatic cancer. Likewise, it is very difficult to differentiate between pancreatic cancer and chronic pancreatitis. The methods of visualization are insufficiently sensitive and the determination of certain genes could enrich our diagnostic opportunities. Considerable attention in this direction has been devoted to the determination and evaluation of the presence of oncogene K-ras. Our initial experience with the determination of K-ras in preparations from patients with pancreatic cancer or with chronic pancreatitis confirmed that K-ras in an oncomarker associated with adenocarcinoma of pancreas, whereas in patients with chronic pancreatitis it occurs in about 10% of the examined samples.

[Antioxidative action of pyridoindoles and N-(alkoxyphenyl)-2-(2-oxo-1-aza-1-cycloalkyl) acetamides in biological, enzymatic and chemical systems]. / Antioxidacní aktivita pyridoindolu a N-(alkoxyfenyl)-2-(2-oxo-1-aza-1-cykloalkyl) acetaminu v biologickém, enzymatickém a chemickém systému.

The luminol-enhanced chemiluminiscence method was used to investigate the antioxidative activity of N-(alkoxyphenyl)-2-(2-oxo-1-aza-1-cykloalkyl) acetamides studied as potential cognitive enhancers and stobadine acylderivatives which form prodrugs with increased lipophilicity. The effect on the production of reactive oxygen metabolites by activated leukocytes was studied in vitro. Furthermore, the total radical-trapping antioxidant parameter was evaluated as the peroxyl radical-trapping capacity and the scavenging effect on the superoxide anion radical (generated by the enzymatic system hypoxanthine/xanthine oxidase) and on the hydroxyl radical (produced in Fenton reaction) were studied. The antioxidative properties of the tested substances were compared with that of stobadine dihydrochloride. Only stobadine and its butyrylderivative have been demonstrated to possess free radical scavenging activity in all systems. Cinnamoylstobadine inhibited only the leukocyte chemiluminiscence activity. The potential cognitive enhancers did not show any antioxidant activity.

[Chronic pancreatitis as a risk factor for pancreatic carcinoma]. / Chronická pankreatitida jako rizikový faktor karcinomu pankreatu.

Carcinoma of the pancreas is a very serious disease as regards early diagnosis, effective therapy and screening of the disease. Possible risk factors of development of carcinoma of the pancreas include chronic pancreatitis. In the submitted investigation the authors evaluated 213 patients under long-term (more than 5 years) dispensary care with the diagnosis of chronic pancreatitis. In these patients they proved unequivocally carcinoma of the pancreas on the background of chronic pancreatitis in 11 instances, incl. 71.8% where from the etiological aspect chronic alcoholic pancreatitis was involved. Practically all patients were smokers, incl. 8 who were regular smokers of more than 10 cigarettes per day for a number of years. Carcinoma of the pancreas is a serious disease, patients with long-term chronic pancreatitis are at risk (prevalence of carcinoma 5.1) and within the framework of dispensary care they must be systematically examined with regard to possible malignant growth on the background of chronic pancreatitis.

Immunosuppressive treatment of Crohn's disease with fistulae.

The rise of fistulae in Crohn's disease has been classed with the disorder complications, although it is a possible component of natural development of the so-called A type (De Dombal classification) or aggressive-perforating type (Greenstein's classification) of this idiopathic intestinal inflammation. Fistulae are accompanying colic localization of Crohn's disease in 20%, ileocolic affection in 40%, where 35% of them are perianal fistulae, and about 34% entero-enteral or entero-cutaneous ones. Other complications (urogenital tract, biliary tract) are mentioned infrequently in literature. Besides surgical approaches in the therapy, dominant post in the conservative area is taken up by an antitumor necrotizing factor, antibiotics and immunosuppressives whose position is, however, the most problematic although the literature references about the effectiveness of azathioprine, 6-mercaptopurine, cyclosporine, tacrolime and methotrexate have had nearly 25-years tradition. The authors present their own experience with applying a combination of cyclosporine, azathioprine in the treatment of perianal fistulae in a set of 21 patients from the period of 1995-2000. In their opinion, the therapy success is limited especially by early starting the treatment (11 cases of effective therapy) and choosing a resolute method that is, according to them, sequential immunosuppression. (Tab. 2, Ref. 32.)