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Dive into the research topics where Katarzyna Iwanik is active.

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Featured researches published by Katarzyna Iwanik.


Acta Histochemica | 2003

Ionic liquids in embalming and tissue preservation.: Can traditional formalin-fixation be replaced safely?

Przemysław Majewski; Agnieszka Pernak; Marian Grzymisławski; Katarzyna Iwanik; Juliusz Pernak

Ionic liquids (ILs) can be used for embalming and tissue preservation. ILs does not cause tissue damage and the tissue colour remains unaltered after treatment. Microscopical morphology of tissues fixed in ILs is of better quality than that of tissues fixed in formalin. Tissue preservation depends on the type of ILs. Best results were obtained with 1-methyl-3-octyloxymethylimidazolium tetrafluoroborate, the density of which resembles that of water. The salt is nonvaporous and when used as a formalin substitute, it eliminates health hazards in the pathological laboratory.


Colloids and Surfaces B: Biointerfaces | 2011

Dielectric studies of the paracetamol–lenticular tissue interactions

E. Marzec; J. Olszewski; E. Grześkowiak; A. Kamińska; A. Bienert; Katarzyna Iwanik

This paper reports on the effect of paracetamol on the dielectric behavior of the rabbit lens. Measurements were performed over the frequency range of 100 Hz-100 kHz in air and at the temperature of 35°C. The frequency dependencies of the relative permittivity and dielectric loss for the control and paracetamol-control lenses are described in terms of a power-low, Debye and Cole-Cole relations. The effect of paracetamol on the dielectric properties of the lens is visible in the lower values of the relative permittivity than those for the control sample at the same frequency. In addition, the relaxations around 18 and 46 kHz for the paracetamol-control lens are shifted to lower frequencies compared with the control lens. The results of this work indicate that the present method is useful in detection of the lens toxicity elicited by overdoses of paracetamol in animal.


Folia Histochemica Et Cytobiologica | 2015

The influence of anti-TNF therapy on CD31 and VEGF expression in colonic mucosa of Crohn’s disease patients in relation to mucosal healing

Piotr Eder; Liliana Lykowska-Szuber; Katarzyna Iwanik; Iwona Krela-Kazmierczak; Kamila Stawczyk-Eder; Przemysław Majewski; Krzysztof Linke; Elaine Kay; Aldona Wozniak

INTRODUCTION Immune-mediated angiogenesis may play an important role in the pathogenesis of inflammatory lesions in Crohns disease (CD). The study aimed to assess the influence of anti-tumour necrosis factor (anti-TNF) therapy on the angiogenesis in relation to microscopic and endoscopic healing in CD patients. MATERIAL AND METHODS Colonic tissue samples from 17 CD patients were taken during colonoscopy before and after anti-TNF therapy. Endoscopic and microscopic severities were estimated using validated scores. Immunohistochemical expression of CD31 and vascular endothelial growth factor (VEGF) were assessed in parallel. RESULTS The expression of CD31 and VEGF decreased significantly after the anti-TNF therapy in parallel to endoscopic improvement; however, the microscopic activity did not change significantly. There was a correlation between the change in CD31 and VEGF expression (p = 0.01; r = 0.6), as well as endoscopic healing (p = 0.04; r = 0.4). CD31 immunoexpression correlated with the number of poly- and mononuclear cells in the infiltrates in the mucosal lamina propria before the therapy (p = 0.02; r = 0.5). CONCLUSIONS We suggest that modulation of vascular proliferation can be a novel option to increase the efficacy of biological therapy in CD.


Folia Histochemica Et Cytobiologica | 2013

Anti-TNF antibodies do not induce the apoptosis of lamina propria mononuclear cells in uninflamed intestinal tissue in patients with Crohn's disease.

Piotr Eder; Liliana Lykowska-Szuber; Iwona Krela-Kazmierczak; Kamila Stawczyk-Eder; Karolina Sterzyńska; Katarzyna Iwanik; Przemysław Majewski; Maciej Zabel; Krzysztof Linke

It is not known if anti-tumor necrosis factor (anti-TNF) agents provoke only apoptosis of lamina propria mononuclear cells (LPMC) engaged in inflammatory processes or whether its a general phenomenon concerning all LPMC. In this study we carried out an immunohistochemical analysis of the expression of several apoptosis-related proteins (active caspase-3, Bax, Bcl-2, Fas, TNFR1, CD4, and CD8) in uninflamed mucosa in Crohns disease (CD) patients treated with anti-TNF agents. 16 CD patients (mean age 34 ± 11, mean disease duration 7 ± 5 years) were included in the study. 10 patients were treated with infliximab and 6 - with adalimumab. The expression of active caspase 3, Bax, Bcl-2, Fas, TNFR1 and CD8 in LPMC did not change significantly after the therapy. We concluded that anti-TNF antibodies did not promote LPMC apoptosis in uninflamed tissues. This is in contrast to the phenomena observed in inflamed tissues. These data show that anti-TNF antibodies rather restore the susceptibility to apoptosis of LPMC in inflamed areas of the gut in CD, than directly induce LPMC apoptosis; otherwise the anti-TNF antibodies should have also induced apoptosis in the uninflamed mucosa.


Gastroenterology Research and Practice | 2016

Usefulness of Endoscopic Indices in Determination of Disease Activity in Patients with Crohn’s Disease

Marcin A. Kucharski; Jacek Karczewski; Dorota Mańkowska-Wierzbicka; Katarzyna Karmelita-Katulska; Elżbieta Kaczmarek; Katarzyna Iwanik; Piotr Rzymski; Marian Grzymisławski; Krzysztof Linke; Agnieszka Dobrowolska

Background. Assessment of endoscopic activity of Crohns disease (CD) is of growing importance both in clinical practice and in clinical trials. The study aimed to assess which of the endoscopic indices used for evaluation of mucosal changes correlates with the currently used clinical indices for determination of disease activity and with the results of histopathological examination. Study. A group of 71 patients with CD and 52 individuals without a diagnosis of GI tract disease as a control group were investigated, considering clinical and histological severity of the disease and the severity of inflammatory changes in the bowel. Evaluation was conducted with the use of clinical, endoscopic, and histopathological indices. Endoscopic indices were then correlated with different clinical and histopathological indices with the aim of finding the strongest correlations. Results and Conclusions. Correlation between the clinical disease activity and the severity of endoscopic lesions in CD was shown in this study to be poor. The results also indicate that the optimal endoscopic index used in the diagnostic stage and in the assessment of treatment effects in CD is Simple Endoscopic Score for Crohns Disease (SES-CD).


European Journal of Gastroenterology & Hepatology | 2016

Applicability of endoscopic indices in the determination of disease activity in patients with ulcerative colitis.

Marcin A. Kucharski; Jacek Karczewski; Dorota Mańkowska-Wierzbicka; Katarzyna Karmelita-Katulska; Marian Grzymisławski; Elżbieta Kaczmarek; Katarzyna Iwanik; Piotr Rzymski; Ewelina Swora-Cwynar; Krzysztof Linke; Agnieszka Dobrowolska

Objective The combination of clinical remission and mucosal healing represents a major goal of different treatment strategies for ulcerative colitis (UC). This study aimed to assess which of the endoscopic indices used to evaluate mucosal changes in UC are correlated with clinical indices currently used to determine disease activity, as well as which of the endoscopic indices are correlated with the Geboes Index used for histological evaluation. It also aimed to find correlations between the currently used clinical activity indices and the histological Geboes Index. Methods A group of 49 patients with a confirmed diagnosis of UC and a group of 52 individuals without a diagnosis of gastrointestinal disease, who constituted the control group, were investigated. All patients were evaluated by colonoscopy, and the severity of mucosal changes was scored in terms of nine different endoscopic indices commonly used in both pharmacological trials and clinical practice. Evaluation was also carried out using clinical and histological indices. Endoscopic indices used for UC were then correlated with different clinical and histological indices to find the strongest correlations. Results and conclusion A high correlation was demonstrated between three of the 11 evaluated clinical indices – Improvement Based on Individual Symptom Scores, Ulcerative Colitis Disease Activity Index, and Schroeder Index – and all nine endoscopic indices – Ulcerative Colitis Endoscopic Index of Severity, Baron Score, Schroeder Index, Feagan Index, Powell–Tuck Index, Rachmilewitz Index, Sutherland Index, Lofberg Index, and Lemman Index. Improvement Based on Individual Symptom Scores was the index with the highest correlation with all the endoscopic indices used for UC. The above indices are recommended for clinical evaluation of UC activity. The Ulcerative Colitis Endoscopic Index of Severity was moderately correlated with a histological index, and it is therefore recommended for routine endoscopic mucosal evaluation in patients with UC.


Archives of Medical Science | 2015

Disturbances in apoptosis of lamina propria lymphocytes in Crohn’s disease

Piotr Eder; Liliana Łykowska-Szuber; Iwona Krela-Kaźmierczak; Kamila Stawczyk-Eder; Katarzyna Iwanik; Przemysław Majewski; Karolina Sterzyńska; Maciej Zabel; Krzysztof Linke

Introduction The aim of this study was to assess the potential mechanisms providing resistance to apoptosis of lamina propria lymphocytes (LPL) directlyin intestinal tissues from patients with Crohns disease (CD). Material and methods Fifty CD patients were enrolled in the study. The control group consisted of healthy patients who underwent surveillance colonoscopy after endoscopic polypectomy. Each CD patient underwent colonoscopy with tissue sampling from inflamed areas of the colon with the assessment of immunohistochemical expression of active caspase 3, Fas, tumour necrosis factor receptor 1 (TNFR1), Bcl-2, Bax, CD4 and CD8. This was compared with healthy intestinal mucosa. Results The expression of active caspase 3 was significantly lower in LPL in CD (0.4 ±0.3 vs. 2.8 ±1.5; p = 0.0002). A statistically significant increase of CD4 and CD8 positive cells was noted in CD (2.3 ±0.5 vs. 1.2 ±0.2, p < 0.0001; 2.1 ±0.3 vs. 1.1 ±0.3, p < 0.0001, respectively). It was associated with a significant increase of the Bcl-2 (6.7 ±2.7 vs. 2.9 ±0.8; p < 0.0001) and a decrease of the Bax protein expression (3.4 ±2.1 vs. 5.5 ±1.8; p < 0.0001) in CD. The expression of Fas and TNFR1 did not differ between the study groups. Conclusions LPL in CD are resistant to apoptosis when compared with physiological conditions. This is probably due to an imbalance in Bcl-2 family proteins. TNFR1-related pathway is probably not involved in disturbances of LPL apoptosis in CD.


Gastroenterology Review | 2010

Evaluation of the treatment efficacy with adalimumab in Crohn’s disease – case report

Piotr Eder; Liliana Łykowska-Szuber; Iwona Krela-Kazimierczak; Katarzyna Iwanik; Katarzyna Karmelita-Katulska; Przemysław Majewski; Krzysztof Linke

Piotr Eder1, Liliana Łykowska-Szuber1, Iwona Krela-Kaźmierczak1, Katarzyna Iwanik2, Katarzyna Karmelita-Katulska3, Przemysław Majewski2, Krzysztof Linke1 1Katedra i Klinika Gastroenterologii, Żywienia Człowieka i Chorób Wewnętrznych Uniwersytetu Medycznego im. Karola Marcinkowskiego w Poznaniu 2Katedra i Zakład Patomorfologii Klinicznej Uniwersytetu Medycznego im. Karola Marcinkowskiego w Poznaniu 3Katedra Radiologii Uniwersytetu Medycznego im. Karola Marcinkowskiego w Poznaniu


Reports of Practical Oncology & Radiotherapy | 2005

Primary multifocal GIST of stomach; a case report

Katarzyna Iwanik; Przemysław Majewski

Summary Background GISTs are CD 117 positive mesenchymal neoplasms, mainly located in tubular GI tract, frequently with a very similar histologic pattern and different malignancy. They typically occur as solitary lesions, whereas their occurence as disseminated tumours is usually associated with spread from a primary site. GISTs have three kinds of histologic pattern, the most common of which is the spindle cell pattern. The diagnosis of GIST is by positive reaction for CD 117 and the results of other immunohistochemical reactions, mainly for smooth muscle markers, nervous tissue markers also for endothelial cells marker (CD 34). Aim The aim of this study was to present a case of primary multifocal GIST of stomach. Case description Two gastric tumours were surgically excised and, after formalin fixation and routine preparation, were tested with antibodies raised against CD 117, desmin, SMA, NSE, S-100 protein, PGP 9.5 and CD 34. The histologic patterns and immunohistochemical results of the two tumours were clearly different. Conclusions Conclusions despite evident differences in size and location of these tumours in the stomach wall, both lesions can be looked upon as bifocal primary GIST.


Food and Chemical Toxicology | 2010

Evaluation of the acute oral toxicity class of tricentric chromium(III) propionate complex in rat

Halina Staniek; Zbigniew Krejpcio; Katarzyna Iwanik

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Przemysław Majewski

Poznan University of Medical Sciences

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Krzysztof Linke

Poznan University of Medical Sciences

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Marian Grzymisławski

Poznan University of Medical Sciences

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Piotr Eder

Poznan University of Medical Sciences

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Kamila Stawczyk-Eder

Poznan University of Medical Sciences

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Agnieszka Dobrowolska

Poznan University of Medical Sciences

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Dorota Mańkowska-Wierzbicka

Poznan University of Medical Sciences

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E. Marzec

Poznan University of Medical Sciences

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Iwona Krela-Kazmierczak

Poznan University of Medical Sciences

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Jacek Karczewski

Poznan University of Medical Sciences

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