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  • Author: Krzysztof Wróblewski x
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Open access

Grzegorz Karbowiak, Krzysztof Solarz, Marek Asman, Zbigniew Wróblewski, Kateryna Slivinska and Joanna Werszko

Abstract

Phoresy is an association in which a small animal clings to a larger one exclusively for transportation. We searched for phoretic mites on fleas and ticks of small mammals. A total of 169 fleas of 7 species were collected in the Białowieża Forest (E Poland) and in Kosewo G órne (NE Poland) in July and August in 2007 and 2008. Moreover, 20 nymphs and 12 females of Ixodes hexagonus (Leach, 1815) were collected in the beaver farm of the Research Station of Polish Academy of Sciences in Popielno (NE Poland) in April and May 2009. Phoretic mites were found on 26 fleas (15.4%) of the following species: Megabothris walkeri (Rothschild, 1902), Megabothris turbidus (Rothschild, 1909), Ctenophthalmus agyrtes (Heller, 1896), and Hystrichopsylla orientalis (Smit, 1956). The mites were located mainly on abdominal sternites. Among ticks, only one female was positive for mites, whose larvae (hypopi) were found on its legs. A total of 6 species of mites were identified. On I. hexagonus, we found Acarus farris (Oudemans, 1905) (53 larvae), Acarus siro (L., 1758) (2 larvae), Acarus nidicolous (Griffiths, 1970) (1 larva), Caloglyphus rhizoglyphoides (Zachvatkin, 1937) (1 larva), and Histiostoma feroniarum (Dufour, 1904) (28 larvae), whereas on fleas, 79 larvae of Acarus nidicolous, 1 male of Tyrophagus putrescentiae (Schrank, 1781), and 1 unidentified trombiculid larva. The last 2 mite specimens were found on M. turbidus. This is the first report on phoretic association of the flea H. orientalis and the tick I. hexagonus with mites

Open access

Robert Cherbański, Krzysztof Wróblewski and Eugeniusz Molga

Abstract

This paper presents a systematic thermogravimetric (TG) study on the kinetics of end-of-life tyre (ELT) pyrolysis. In the experimental part of this work, TG results are compared for tyre samples of different mass and size. This shows that the conduction resistance in the milligram scale (up to ~100 mg) tyre sample can be neglected. A comparison of experimental results demonstrates that the characteristic maxima on the DTG curve (the first derivative of TG signal) shift towards higher temperatures for higher heating rates. This phenomenon is explained to have kinetic origin and it is not caused by the internal heat transfer resistance. In the modelling part of this work, the kinetic parameters of the Three-Component Simulation Model (TCSM) are calculated and compared to the literature values. Testing of the kinetic model is carried out using experiments with a varying heating rate. This shows the limitation of the simplified kinetic approach and the appropriate selection method of the kinetic parameters.

Open access

Marek Krawczyk, Michał Grąt, Oskar Kornasiewicz, Krzysztof Zieniewicz, Paweł Nyckowski, Waldemar Patkowski, Ireneusz Grzelak, Krzysztof Dudek, Tadeusz Wróblewski and Rafał Paluszkiewicz

Liver transplantation in the treatment of patients with hepatocelular carcinoma

The aim of the study was to analyse liver transplantation results in patients with hepatocellular carcinoma, considering selected factors.

Material and methods. The study group comprised 82 patients subject to liver transplantation at the Department of General, Transplant and Liver Surgery, Warsaw Medical University, due to hepatocellular carcinoma. Retrospective analysis concerned the period between 2001 and 2010. Distant survival results were evaluated, depending on whether Milan criteria were fulfilled, and the preoperative level of alpha-fetoprotein estimated. The obtained results were subject to statistical analysis. p<0.05 was considered as statistically significant.

Results. Mean survival time considering patients subject to liver transplantation, due to hepatocellular carcinoma amounted to 66.7 months (95% PU 58.9-74.4), while survival without tumor recurrence - 62.3 months (95% PU 54-70.6). The one, three and five - year survival rate was 88.7%, 74.8% and 72.0%, respectively. Survival without tumor recurrence was 87.5%, 67.1% and 67.1%, respectively. The overall survival of patients fulfilling the Milan criteria (44 of 82 patients - 53.7%) was significantly longer, in comparison to patients not fulfilling the above-mentioned (74.4 and 48.3 months, respectively, p=0.025). A significant difference was also observed, considering the overall survival in the absence of cancer recurrence (72.5 and 42.4 months, respectively, p=0.007). Considering patients not fulfilling the Milan criteria who presented with preoperative alpha-fetoprotein levels > 100 ng/ml, overall survival was shorter, as compared to the mean survival rate: 32.5 and 64.4 months, respectively, p = 0.009. Similar values were obtained in case of patients without tumor recurrence (27 and 57.1 months, p=0.011).

Conclusions. The obtained results confirmed the significant value of Milan criteria, when qualifying patients with hepatocellular carcinoma for liver transplantation. The above-mentioned also showed the potential value of preoperative alpha-fetoprotein level measurements, not only in the diagnostics and early hepatocellular carcinoma diagnosis (patients with cirrhosis), but also in the prediction of survival and tumor recurrence after liver transplantation.

Open access

Marek Krawczyk, Michał Grąt, Karolina Grąt, Karolina Wronka, Maciej Krasnodębski, Jan Stypułkowski, Łukasz Masior, Wacław Hołówko, Joanna Ligocka, Paweł Nyckowski, Tadeusz Wróblewski, Rafał Paluszkiewicz, Waldemar Patkowski, Krzysztof Zieniewicz, Leszek Pączek, Piotr Milkiewicz, Urszula Ołdakowska-Jedynak, Bogusław Najnigier, Krzysztof Dudek, Piotr Remiszewski, Ireneusz Grzelak, Oskar Kornasiewicz, Marcin Kotulski, Piotr Smoter, Mariusz Grodzicki, Michał Korba, Piotr Kalinowski, Michał Skalski, Krzysztof Zając, Rafał Stankiewicz, Marta Przybysz, Bartosz Cieślak, Łukasz Nazarewski, Małgorzata Nowosad, Konrad Kobryń, Michał Wasilewicz, Joanna Raszeja-Wyszomirska, Jolanta Piwowarska, Dorota Giercuszkiewicz, Joanna Sańko-Resmer, Sławomir Rejowski, Monika Szydłowska-Jakimiuk, Barbara Górnicka, Bogna Wróblewska-Ziarkiewicz, Michał Mazurkiewicz, Grzegorz Niewiński, Jacek Pawlak and Ryszard Pacho

Abstract

Liver transplantation is a well-established treatment of patients with end-stage liver disease and selected liver tumors. Remarkable progress has been made over the last years concerning nearly all of its aspects.

The aim of this study was to evaluate the evolution of long-term outcomes after liver transplantations performed in the Department of General, Transplant and Liver Surgery (Medical University of Warsaw).

Material and methods. Data of 1500 liver transplantations performed between 1989 and 2014 were retrospectively analyzed. Transplantations were divided into 3 groups: group 1 including first 500 operations, group 2 including subsequent 500, and group 3 comprising the most recent 500. Five year overall and graft survival were set as outcome measures.

Results. Increased number of transplantations performed at the site was associated with increased age of the recipients (p<0.001) and donors (p<0.001), increased rate of male recipients (p<0.001), and increased rate of piggyback operations (p<0.001), and decreased MELD (p<0.001), as well as decreased blood (p=0.006) and plasma (p<0.001) transfusions. Overall survival was 71.6% at 5 years in group 1, 74.5% at 5 years in group 2, and 85% at 2.9 years in group 3 (p=0.008). Improvement of overall survival was particularly observed for primary transplantations (p=0.004). Increased graft survival rates did not reach the level of significance (p=0.136).

Conclusions. Long-term outcomes after liver transplantations performed in the Department of General, Transplant and Liver Surgery are comparable to those achieved in the largest transplant centers worldwide and are continuously improving despite increasing recipient age and wider utilization of organs procured from older donors.

Open access

Marek Krawczyk, Michał Grąt, Krzysztof Barski, Joanna Ligocka, Arkadiusz Antczak, Oskar Kornasiewicz, Michał Skalski, Waldemar Patkowski, Paweł Nyckowski, Krzysztof Zieniewicz, Ireneusz Grzelak, Jacek Pawlak, Abdulsalam Alsharabi, Tadeusz Wróblewski, Rafał Paluszkiewicz, Bogusław Najnigier, Krzysztof Dudek, Piotr Remiszewski, Piotr Smoter, Mariusz Grodzicki, Michał Korba, Marcin Kotulski, Bartosz Cieślak, Piotr Kalinowski, Piotr Gierej, Mariusz Frączek, Łukasz Rdzanek, Rafał Stankiewicz, Konrad Kobryń, Łukasz Nazarewski, Dorota Leonowicz, Magdalena Urban-Lechowicz, Anna Skwarek, Dorota Giercuszkiewicz, Agata Paczkowska, Jolanta Piwowarska, Remigiusz Gelo, Paweł Andruszkiewicz, Anna Brudkowska, Renata Andrzejewska, Grzegorz Niewiński, Beata Kilińska, Aleksandra Zarzycka, Robert Nowak, Cezary Kosiński, Teresa Korta, Urszula Ołdakowska-Jedynak, Joanna Sańko-Resmer, Bartosz Foroncewicz, Jacek Ziółkowski, Krzysztof Mucha, Grzegorz Senatorski, Leszek Pączek, Andrzej Habior, Robert Lechowicz, Sławomir Polański, Elżbieta Leowska, Ryszard Pacho, Małgorzata Andrzejewska, Olgierd Rowiński, Sławomir Kozieł, Jerzy Żurakowski, Bogna Ziarkiewicz-Wróblewska, Barbara Górnicka, Piotr Hevelke, Bogdan Michałowicz, Andrzej Karwowski and Jerzy Szczerbań

1000 Liver Transplantations at the Department of General, Transplant and Liver Surgery, Medical University of Warsaw - Analysis of Indications and Results

The aim of the study was to analyze indications and results of the first one thousand liver transplantations at Chair and Clinic of General, Transplantation and Liver Surgery, Medical University of Warsaw.

Material and methods. Data from 1000 transplantations (944 patients) performed at Chair and Clinic of General, Transplantation and Liver Surgery between 1994 and 2011 were analyzed retrospectively. These included 943 first transplantations and 55 retransplantations and 2 re-retransplantations. Frequency of particular indications for first transplantation and retransplantations was established. Perioperative mortality was defined as death within 30 days after the transplantation. Kaplan-Meier survival analysis was used to estimate 5-year patient and graft survival.

Results. The most common indications for first transplantation included: liver failure caused by hepatitis C infection (27.8%) and hepatitis B infection (18%) and alcoholic liver disease (17.7%). Early (< 6 months) and late (> 6 months) retransplantations were dominated by hepatic artery thrombosis (54.3%) and recurrence of the underlying disease (45%). Perioperative mortality rate was 8.9% for first transplantations and 34.5% for retransplantations. Five-year patient and graft survival rate was 74.3% and 71%, respectively, after first transplantations and 54.7% and 52.9%, respectively, after retransplantations.

Conclusions. Development of liver transplantation program provided more than 1000 transplantations and excellent long-term results. Liver failure caused by hepatitis C and B infections remains the most common cause of liver transplantation and structure of other indications is consistent with European data.