Vit Martin Matejka

Publications (5) View all

• Article: The role of cetuximab in the treatment of metastatic colorectal cancer.

  Lubos Holubec, Vaclav Liska, Vit M Matejka, Ondrej Fiala, Jana Dreslerova, Petra Mrazkova, Vladislav Treska, Jindrich Finek
  [show abstract] [hide abstract]
  ABSTRACT: Targeted biological therapy is becoming a standard in personalized medicine for patients with advanced stages of cancer. Treatment with cetuximab, an anti-epidermal growth factor receptor (EGFR) antibody, represents an example of personalized anticancer therapy for patients with metastatic colorectal cancer and wild (non-mutated) type of the Kirsten rat sarcoma viral oncogene (KRAS). Here the role of cetuximab in treating metastatic colorectal cancer is discussed with a focus on the treatment of hepatic metastases.
  Anticancer research 09/2012; 32(9):4007-11. · 1.73 Impact Factor
• Article: [Effect of biological glues on vascular wall in an experimental model of aortic dissection].

  T Martinca, M Jonák, Z Tonar, K Witter, V M Matejka, S Rokosný
  [show abstract] [hide abstract]
  ABSTRACT: The use of biological glues and their application between the two dissection layers and into the anastomosis region is a common integral part of surgical management of thoracic aortic dissections. The aim of the experimental study was to assess and evaluate histopathological changes of vascular wall following deposition of the following three types of glue--GRF, Tissucol, Bioglue, based on qualitative and quantitative parameters. The secondary aim of the study was to assess dynamics of these changes depending on the glue effect duration and to formulate expected behaviour of the vascular wall during the time beyond the experimental period. The dissection model was performed with pigs of the same gender and age, assigned to four groups. Different glues were used to close artificial infrarenal aortic dissections in Group 1-3, while direct suturing and no glue was used to close false lumini in Group 4. Samples of the dissected aorta were then collected at Month 1, 6 and 12 and then histologically examined. Upon assessment of the whole group of qualitative and quantitative parameters, the most significant changes in the smooth muscle histological picture were observed with the use GRF glue. The smooth muscle changes following the Bioglue application and, in particular, Tissucol glue application, are similar to changes observed in Group 4, where no glue was used. Based on the results, the authors present a hypothesis that, in a long-time horizont, vascular wall destructions, eventually redissections, are likely to occur more frequently in patients, in whom GRF glue is used.
  Rozhledy v chirurgii: měsíčník Československé chirurgické společnosti 02/2011; 90(2):134-40.
• Source

  Available from: Zbynek Tonar

  Article: Tissue reaction to three different types of tissue glues in an experimental aorta dissection model: a quantitative approach.

  Kirsti Witter, Zbynek Tonar, Vít Martin Matejka, Tomás Martinca, Michael Jonák, Slavomír Rokosný, Jan Pirk
  [show abstract] [hide abstract]
  ABSTRACT: Tissue glues are used during surgical treatment of acute aorta dissection although some glues release toxic products and thus alter the histological structure of the vessel wall. The aim of our study was to use a porcine experimental model of infrarenal aorta dissection to compare histological changes of the vessel wall 1, 6 and 12 months after application of BioGlue, Gelatin-resorcin-formaldehyde (GRF) glue and Tissucol. For quantification, stereological methods were used. All types of glue caused stenosis, GRF most and Tissucol least severely. With increasing postoperative survival time, stenosis was again reduced. Elastine length density decreased with increasing survival time in Control as well as in all Experimental groups. The immunohistochemical phenotype of vascular smooth muscle cells was similar in Tissucol and Control samples. In GRF samples, actin, desmin and vimentin expression changed most severely. Similarly, number and distribution of vasa vasorum in the aortic wall was altered most severely in GRF samples. They tended to return to normal with increasing postoperative survival time, but at a slow rate in the GRF samples. It can be concluded that GRF causes the most severe histopathological changes within the treated aorta, which could be a reason for late failures of dissection surgery. However, glue handling and adhesive properties have to be taken into account, too, when certain glue is chosen for surgical intervention. Increased inflammation and vascularisation might even stabilise the aortic wall. Long-term experimental studies would be helpful to assess healing processes after initial disorganisation of the aortic wall structure.
  Histochemie 11/2009; 133(2):241-59. · 2.59 Impact Factor
• Source

  Available from: Zbynek Tonar

  Article: Morphology and mechanical properties of the subrenal aorta in normotensive and hypertensive rats.

  Petra Kochova, Zbynek Tonar, Vit M Matejka, Jitka Sviglerova, Milan Stengl, Jitka Kuncova
  [show abstract] [hide abstract]
  ABSTRACT: This work focuses on the morphological and mechanical changes in the wall of the subrenal aorta in rats suffering from arterial hypertension and chronic renal failure induced by subtotal nephrectomy (NX). The quantitative structural parameters were assessed using stereological methods. The mechanical properties were determined using uniaxial tensile tests. Morphological results showed no significant differences in the wall structure of NX rats ten days following the subtotal nephrectomy in comparison with the control animals. Pronounced structural changes appeared ten weeks after the nephrectomy. The area of the profile of the arterial lumen, the volume fraction of elastin, and the elastin lamellar number in the tunica media were significantly higher in the NX rats than in the control animals. The values of the volume fraction of the smooth muscle cells in the tunica media and the lamellar unit thickness were significantly lower for the NX animals. Mechanical results showed that both kinds of tissues were characterized by a non-linear response when subjected to the tensile test. The moduli of elasticity of subrenal aortas in control and NX animals were different only for large deformations: NX samples had higher stiffness. The cyclic loading resulted in a time-dependent response for both tissue types. The results obtained from the NX rats ten days as well as ten weeks after operation suggested an outward hypertrophy of the aorta. The subrenal aortas of the NX animals had less strength and were less extensible than those of the control animals.
  Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia 01/2009; 152(2):239-45.
• Article: Cytokeratin serum biomarkers in patients with colorectal cancer.

  S Holdenrieder, P Stieber, V Liska, V Treska, O Topolcan, J Dreslerova, V M Matejka, J Finek, L Holubec
  [show abstract] [hide abstract]
  ABSTRACT: Circulating cytokeratins have shown to be important for management of patients with lung cancer. Here we investigated their role for differential diagnosis, therapy monitoring and prognosis in colorectal cancer (CRC). Pretherapeutic levels of cytokeratin-19 fragments (CYFRA 21-1), carcino-embryonic antigen (CEA) and cancer antigen (CA) 19-9 were measured in 42 patients with CRC, 45 with benign colorectal diseases and 51 healthy controls. Furthermore, courses of CYFRA 21-1, tissue polypeptide antigen (TPA), tissue polypeptide specific antigen (TPS), M30-antigen, CEA and CA 19-9 were analyzed in prospectively collected sera of 15 patients with CRC during primary chemotherapy and were correlated with therapy response and overall survival (OS). Similar to CEA and CA 19-9, CYFRA 21-1 was significantly elevated in serum from patients with CRC (median 2.1 ng/ml) as compared with healthy (1.2 ng/ml; p<0.0001) and benign gastrointestinal controls (1.7 ng/ml; p=0.0178) and showed stage dependency in CRC (p=0.0118). CYFRA 21-1 correlated with CEA in benign diseases and CRC but not with CA 19-9. The best discrimination between healthy controls and patients with CRC was achieved by combination of CYFRA 21-1 and CA 19-9 (area under the curve; AUC=86.7%), while the combination of CEA and CA 19-9 discriminated best between benign diseases and CRC (AUC=73.9%). In CRC patients during primary chemotherapy, levels of cytokeratins CYFRA 21-1, TPA, TPS, CEA and CA 19-9 tended to be higher in patients with poor response to therapy and with poor prognosis. Cytokeratins are elevated in patients with CRC and show some association with response to primary therapy and prognosis.
  Anticancer research 05/2012; 32(5):1971-6. · 1.73 Impact Factor