Correlation of carbonic anhydrase IX expression with clinico-morphological parameters, hormonal receptor status and HER-2 expression in breast cancer.

UNLABELLED: The hypoxia-inducible protein carbonic anhydrase IX is widely expressed in most human cancers, including breast carcinomas. CA IX attracts significant interest due to its strong association with neoplasms and its absence from corresponding normal tissues, suggesting its potential to serve as a promising diagnostic biomarker. This protein comes into the limelight also as a valuable prognostic and predictive parameter. Immunohistochemically, we examined the expression of this protein in 84 cases of invasive breast carcinoma to determinate the association with clinico-morphological and biological parameters such as age of patients, grade, stage and size of primary tumor, lymph node metastasis, vascular invasion as well as hormone receptor status and HER-2 expression. In each case, the subcellular localization of CA IX antigen, the intensity of staining and the percentage of labeled cells were assessed. Overall, CA IX was expressed in 34 cases (40.5%). The statistical analysis revealed a significant correlation between subcellular localization of CA IX and the age of patients. Furthermore, significant correlations were also found between the grade, estrogen and progesterone status and all immunohistochemical characteristics of CA IX expression (the subcellular localization of CA IX antigen, the intensity of staining and the percentage of labeled cells). We point out that mostly membrane or combined membrane and cytoplasmic positivity together with a higher intensity of CA IX immunoreactivity are associated with poor prognostic parameters, such as tumor grade 3 and also with negative estrogen and progesterone receptor status which may influence therapeutic approach. However, no significant correlations were shown with remaining clinico-morphological and biological parameters. We next investigate the relationship between CA IX expression in the group of invasive ductal carcinomas and the group of invasive lobular carcinomas and other less frequent types of breast carcinoma. There was, however, no significant difference. Our results suggest that moderate to strong membrane and combined membrane and cytoplasmic localization of CA IX may represent a valuable tumor biomarker as well as a promising prognostic and predictive parameter in invasive breast cancer. KEYWORDS: breast carcinoma, carbonic anhydrase IX, immunohistochemistry, clinico-morphological and biological parameters.

Combination of hyperhomocysteinemia and ischemic tolerance in experimental model of global ischemia in rats.

Epidemiological studies show positive relationship between mild-to-moderate hyperhomocysteinemia (hHcy) and the risk of cerebrovascular diseases. The study determines whether hyperhomocysteinemia (risk factor of brain ischemia) alone or in combination with the ischemic preconditioning (IPC) affects the ischemia-induced neurodegenerative changes and imbalance in MAPK/p-ERK1/2 and MAPK/p-p38 expression in the rat brains. hHcy was induced by subcutaneous administration of homocysteine (0.45 µmol/g body weight) twice a day at 8 h intervals for 14 days. Rats were preconditioned by 5 min ischemia and 2 days later, 15 min of global forebrain ischemia was induced by four vessel occlusion. We observed that hHcy alone significantly increased neurodegeneration by Fluoro-Jade C and TUNEL possitive cells in hippocampus as well as in cortex. We found elevated level of MAPK/p-ERK and decreased level of MAPK/p-p38 after pre-ischemic challenge by Western blot and fluorescent immunohistochemistry. In conclusion, preconditioning even if combined with hHcy could preserve the neuronal tissue from lethal ischemic effect. This study provides evidence for the interplay and tight integration between ERK and p38 MAPKs signalling mechanisms in response to the hHcy and also if in association with brain ischemia/IPC challenge in the rat brain.

Hyperhomocysteinemia as a risk factor for the neuronal system disorders.

Elevated concentration of the homocysteine (Hcy) in human tissues, resulting either from mutations in genes enconding Hcy-metabolizing enzymes, or from deficiences of folic acid has recognized cytotoxic effect. Even a mild Hcy level increase is a risk factor for cardiovascular diseases and stroke in humans and also a risk factor for neurodegenerative disordes, such as dementia, or Alzheimer's disease. However, it is not yet clear whether homocysteine is a marker, or a causative agent. We present here an overview of recent data on the homocysteine metabolism and on the genetic and the metabolic causes of hyperhomocysteinemia-related pathologies in humans. In context of our results which detected an increased oxidative stress in hyperhomocysteinemic rats we discuss here the role of free radicals in this disorder. Imbalance between homocysteine auto-oxidation, production of reactive metabolites and cellular antioxidant defence induced by hyperhomocysteinemia results to cytotoxicity by oxidizing membrane lipids and proteins. Consequently, protein thiolation and homocysteinylation results in the structural and functional modifications of cells, including neuronal ones. It is our hope that identification of prophylacting factors effective in the prevention of toxic effect of Hcy would lead to improved therapeutics, especially the brain tissue.

p-ERK involvement in the neuroprotection exerted by ischemic preconditioning in rat hippocampus subjected to four vessel occlusion.

Global brain ischemia-reperfusion causes delayed cell death in hippocampal CA1 (cornus ammonis 1) pyramidal neurons after reperfusion. Ischemic tolerance evoked by preconditioning (IPC) represents a phenomenon of CNS adaptation to any subsequent ischemia. This paper was designed to describe changes in the mitogen-activated protein kinases (MAPK) protein pathways of the hippocampal area following by IPC. Ischemia was induced by a 4-vessels occlusion (4VO) and the rats were preconditioned by a non-injurious ischemia. Apoptotic markers were used to follow the degeneration process. Western blot and immunohistochemistry identified p-ERK (phosphorylated extracellular signal-regulated protein kinase) and p38 proteins in injured hippocampal areas. P-ERK quantification increased after IPC and reached the highest level at 24 hours after ischemia. Interestingly, neuroprotection induced by IPC lead to the opposite effect on MAPK/p38, where the level was lowest at 24 hours after ischemia. Taken together, the present study clearly demonstrates that p-ERK takes part in complex cascades triggered by IPC in the selectively vulnerable hippocampal region. In addition, paper describes a crosstalk between p-ERK and p-p38 which occurs after preconditioning maneuver in 4VO model of global ischemia.

Clinical evaluation of a novel population-based regression analysis for detecting glaucomatous visual field progression.

BACKGROUND: The distinction of real progression from test variability in visual field (VF) series may be based on clinical judgment, on trend analysis based on follow-up of test parameters over time, or on identification of a significant change related to the mean of baseline exams (event analysis). The aim of this study was to compare a new population-based method (Octopus field analysis, OFA) with classic regression analyses and clinical judgment for detecting glaucomatous VF changes. PATIENTS AND METHODS: 240 VF series of 240 patients with at least 9 consecutive examinations available were included into this study. They were independently classified by two experienced investigators. The results of such a classification served as a reference for comparison for the following statistical tests: (a) t-test global, (b) r-test global, (c) regression analysis of 10 VF clusters and (d) point-wise linear regression analysis. RESULTS: 32.5 % of the VF series were classified as progressive by the investigators. The sensitivity and specificity were 89.7 % and 92.0 % for r-test, and 73.1 % and 93.8 % for the t-test, respectively. In the point-wise linear regression analysis, the specificity was comparable (89.5 % versus 92 %), but the sensitivity was clearly lower than in the r-test (22.4 % versus 89.7 %) at a significance level of p = 0.01. A regression analysis for the 10 VF clusters showed a markedly higher sensitivity for the r-test (37.7 %) than the t-test (14.1 %) at a similar specificity (88.3 % versus 93.8 %) for a significant trend (p = 0.005). In regard to the cluster distribution, the paracentral clusters and the superior nasal hemifield progressed most frequently. CONCLUSIONS: The population-based regression analysis seems to be superior to the trend analysis in detecting VF progression in glaucoma, and may eliminate the drawbacks of the event analysis. Further, it may assist the clinician in the evaluation of VF series and may allow better visualization of the correlation between function and structure owing to VF clusters.

Effects of long-term oxygen treatment on alpha-ketoglutarate dehydrogenase activity and oxidative modifications in mitochondria of the guinea pig heart.

OBJECTIVE: Oxygen therapy is used for the treatment of various diseases, but prolonged exposure to high concentrations of O(2) is also associated with formation of free radicals and oxidative damage. METHODS: In the present study we compared alpha-ketoglutarate dehydrogenase (KGDH) activity and mitochondrial oxidative damage in the hearts of guinea pigs after long-term (17 and 60 h) oxygenation with 100% normobaric O(2) and with partially negatively (O(2 neg)) or positively (O(2 posit)) ionized oxygen. RESULTS: Inhalation of O(2) led to significant loss in KGDH activity and thiol group content and accumulation of bityrosines. Inhalation of O(2 neg) was accompanied by more pronounced KGDH inhibition, possibly due to additional formation of protein-lipid conjugates. In contrast, O(2 posit) prevented loss in KGDH activity and diminished mitochondrial oxidative damage. CONCLUSIONS: These findings suggest that oxygen treatment is associated with impairment of heart energy metabolism and support the view that inhalation of O(2 posit) optimizes the beneficial effects of oxygen therapy.

Detection of visual field progression in glaucoma.

BACKGROUND: The aim of this study was to compare an event analysis and a trend analysis for the detection of progression in glaucomatous visual field loss. PATIENTS AND METHODS: Excluding initial fields (Octopus, Haag-Streit AG, Köniz, Switzerland), baseline was defined as the average result of the second and third examinations. Eyes with at least 6 additional fields entered the study. The event analysis used the method of the Collaborative Normal Tension Glaucoma Study, and the trend analysis was based on a point-wise linear regression analysis. RESULTS: Of 251 glaucoma patients, 235 left eyes and 225 right eyes qualified for the study. Using the event analysis, 44 series suggested a progressive damage, while the point-wise regression approach disclosed only 14 progressing series. In 9 eyes, the two approaches were concordant. Among the latter, 1 - 5 additional fields were necessary in 7 series to disclose progression using the trend analysis. In one series, the event analysis showed progression 7 examinations later. CONCLUSIONS: The point-wise linear regression analysis classified fewer cases as progressing than the event analysis and determined progression later.

[Serological survey and vaccination against viral hepatitis A in health care providers at the Clinic of Infectious Diseases in Ostrava]. / Sérologický prehled a vakcinace proti virové hepatitide A u zdravotníku na infekcní klinice v Ostrave.

STUDY OBJECTIVE: The health care providers of the Clinic of Infectious Diseases in Ostrava were screened for immunity to hepatitis A virus (HAV) in an attempt to provide vaccination against hepatitis A to non-immune persons. STUDY SUBJECTS AND METHODS: A cohort of 101 health care providers of the Clinic of Infectious Diseases, i.e. 10 physicians, 56 nurses and 35 nursing auxiliaries, were screened. Total anti-HAV antibodies were determined by ELISA and the subjects not reaching the protective level of anti-HAV antibodies were considered as non-immune. Vaccination against hepatitis A was recommended to all of the non-immune persons. RESULTS: Immunity to HAV was detected in 41 (41%) of 101 screened subjects. Immunity was increasing with age, being found in 8% of subjects under 40 years of age and 59 % of older subjects, in 2 (20%) physicians, 23 (41%) nurses and 16 and nursing auxiliaries. Vaccination of 58 non-immune subjects was conducted without complications. CONCLUSION: The prevalence rates of total anti-HAV antibodies in health care providers of the Clinic of Infectious Diseases showed a continuing upward trend with age and were practically the same as in the community.