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1

Otrzymywanie polilaktydowych rusztowań komórkowych o strukturze gąbczastej – badania wstępne i optymalizacja procesu

Kruk A., Gadomska-Gajadhur A., Ruśkowski P., Chwojnowski A., Synoradzki L.

Polimery

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2017

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T. 62, nr 2

118--126

PL

Otrzymywano polilaktydowe rusztowania o strukturze gąbczastej przeznaczone do hodowli komórek nabłonka walcowatego (średnica ~ 60 µm). Przeprowadzono badania wstępne i optymalizację procesu. Wyznaczono równanie regresji określające wpływ stosunku masowego porofor/polilaktyd, stężenia polilaktydu w 1,4-dioksanie oraz stosunku objętościowego MeOH/H2O w kąpieli żelującej na średnicę powstających porów. Opracowano warunki, w których w przełomie rusztowania otrzymuje się możliwie największe pory (o średnicy z zakresu 50–100 µm).

EN

A study on the preparation of polylactide scaffolds for columnar epithelium cells (size ~ 60 µm) were presented. Preliminary studies and optimization of the process were carried out. The regression equation describing the influence of pore precursor/polylactide weight ratio, concentration of polylactide in 1,4-dioxane and volume ratio of MeOH/H2O in the coagulation bath on the diameter of the pores has been established. The optimal conditions which yield the biggest pores in the range 50–100 µm in the cross-section were designed.

2

Use of siliconised infant endotracheal tubes reduces work of breathing under turbulent flow

Stankiewicz B., Rawicz M., Darowski M., Zielinski K., Kozarski M., Chwojnowski A.

Biocybernetics and Biomedical Engineering

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2017

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Vol. 37, no. 1

59--65

EN

The high resistance of an infant endotracheal tube (ETT) can markedly impair ventilation and gas exchange. Since some manufacturers cover the inner surface of their ETTs with a silicon layer in order to diminish deposition and ease mucous evacuation from airway, via surface roughness decrease, we assessed whether the silicon layer may affect tube resistance, work of breathing and other parameters of ventilation. We compared SUMI (Poland) non-siliconised and siliconised polyvinyl chloride ETTs (2.5, 3.0 and 4.0 mm ID), twenty of each type and size combination. Simulating volume-controlled ventilation with the hybrid (numerical–physical) lung models of a premature infant and a 3-month-old baby peak inspiratory pressure (PIP), peak inspiratory and expiratory flow (PIF, PEF), (patient + ETT) inspiratory and expiratory airway resistance (Rins, Rexp) and work of breathing by ventilator (WOBvt) were measured. Additionally, images of the both type surfaces were taken using Hitachi TM-1000 electron microscope. When 2.5 and 3.0 mm ID ETTs were examined, laminar flow (Re <2300) across the tube was observed, and there were no clinically significant differences in the ventilation param-eters between non-siliconised and siliconised tubes. Whereas, when 4 mm ID ETTs were tested, turbulent flow was observed, and PIP, Rins, Rexp and WOBvt were significantly lower (5%, 17%, 17%, and 7%, respectively) (P < 0.05), but PIF and PEF were significantly higher (8%, 14%) (P < 0.05). Thus, the silicone inner surface of ETT offers less resistance and WOBvt in presence of turbulent flow. However, artifacts observed on the surface of non-siliconised and siliconised ETTs can potentially impair ventilation.

3

Effects of hypochlorite treatment on transport-separation properties of polysulfone capillary membranes

Wojciechowski C., Chwojnowski A., Łukowska E.

Problemy Eksploatacji

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2013

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nr 3

17--26

EN

Different types of polysulfone capillary membranes supplemented with porophores were obtained. The membranes were treated with sodium hypochlorite using the flowing method. The membrane ultrafiltration and retention was evaluated for chosen markers before and after treatment. Ultrafiltration increase and retention decrease for polyethylene glycols were observed, and there was not a difference in bovine albumin retention for post-treatment membranes. Hypochlorites caused porophores removal from the membrane structure resulting in opening the pore passages and increasing permeability without increasing pore size.

PL

Obróbce poddano różne typy kapilarnych membran polisulfonowych zawierających porofory. Membrany traktowano podchlorynem sodu metodą przepływową. Filtrowalność oraz retencję membran ultrafiltracyjnych przed i po obróbce oceniano za pomocą wybranych markerów. Membrany poddane obróbce charakteryzowały się wyższą filtrowalnością i niższą retencją dla glikolu polietylenowego przy niezmienionej retencji albuminy bydlęcej. Obróbka podchlorynem sodu spowodowała zmniejszenie ogólnej porowatości membran ultrafiltracyjnych i jednocześnie zwiększenie udziału porów otwartych, dzięki czemu wzrosła przepuszczalność membrany bez wzrostu rozmiarów porów.

4

Studies on the structure of semi-permeable membranes by means of SEM problems and potential sources of errors

Chwojnowski A., Wojciechowski C., Lewińska D., Łukowska E., Nowak J., Kupikowska-Stobba B., Grzeczkowicz M.

Biocybernetics and Biomedical Engineering

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2012

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Vol. 32, no. 1

51-64

EN

The effect of sputtering with a conductor of the semi-permeable membranes surface on SEM pictures obtained is presented. On the example of photomicrographs of several different types of semi-permeable membranes, changes in the appearance of various membrane surfaces, uncovered and sputtered with thicker and thicker layers of the conductor are presented. It has been shown, how essential differences in the appearance of the studied material can be caused by the deposited conductor. It has been shown what errors in the interpretation of SEM images can be caused by applying the sputtered conductor layer with a thickness insufficient to the structure and properties of the studied material. Necessity of minimizing the layer thickness of the sputtered conductor and experimental determination of the sputtered layer thickness was found. Appropriateness of taking the pictures in the mode without sputtering and necessity of comparing the pictures with and without sputtering have been suggested. The useful way of carrying out magnifications' of membranes made of polymers of low melting points has been also presented.

5

Preparation of sulfonated polysulfone membrane for enzymes immobilisation

Łukowska E., Wojciechowski C., Chwojnowski A., Dudziński K., Sabalińska S., Ciechanowska A., Czapiewska G.

Biocybernetics and Biomedical Engineering

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2012

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Vol. 32, no. 2

77-86

EN

The paper presents a method for the preparation of sulfonated polysulfone in order to receive a matrix to immobilisation of biomolecules. Optimum conditions of the synthesis are described. The phase inversion method was used to prepare a sulfonated polysulfone membrane and then urease was immobilized on the surface of the prepared matrix. Comparison of activity of native urease and the immobilized urease is presented.

6

Membranes' porosity evaluation by computer-aided analysis of SEM images – a preliminary study

Chwojnowski A., Przytulska M., Wierzbicka D., Kulikowski J., Wojciechowski C.

Biocybernetics and Biomedical Engineering

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2012

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Vol. 32, no. 4

65-75

EN

The problem of quality control of membranes destined for medical applications is presented. The shape of the membranes surface, its structure, porosity and coarseness are of importance in contact with live cells or simply with live tissue, and as such they should be controlled. For this purpose, scanning electron microscopy (SEM) in our work was used. Results of capillary polysulphone (PSF) 70000 m.m. and polyetherosulphone (PES) 42000 m.m. membranes examination are described. An attempt to apply the computer-aided SEM images processing methods to the membranes' porosity evaluation was made and is presented in the paper. In particular, an approach to segmentation of contours of micropores in the visualized membranes' sections and to evaluation of their morphological parameters is described. An attempt to an approximate statistical reconstruction of 3-dimensional structure of micropores on the basis of collections of 2-dimensional membranes' sections is also described.

7

Culture of human autologous chondrocytes on polysulphonic membrane - preliminary studies

Płończak M., Czubak J., Chwojnowski A., Kupikowska-Stobba B.

Biocybernetics and Biomedical Engineering

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2012

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Vol. 32, no. 3

63-67

EN

This work investigated an effective method of isolation and culture of human autologous chondrocytes placed on a polysulphonic membrane. The cartilage was taken from the hip joint of 78 years old woman who underwent total hip ar throplasty due to idiopatic arthrosis and from the knee of 46 years old man with cartilage lesion from non-weight bear area. The cells were released from the matrix in the course of enzymatic digestion. The isolated cells were placed with parts of polysulphonic membrane in the same culture flask and incubated. Due to evaluation the weight of tissue grown on the polysulphonic membrane the elementary analysis was performed. The elementary analysis of the polysulphonic membrane slices after ten weeks of the culture revealed higher concentration of the tissue on one part of the membrane in case of the older woman - 0.726 mg of protein per 1 mg of the membrane then in case of man - 0.513 mg per 1 mg. The established method of isolation and culture of chondrocytes is effective enough to provide a sufficient number of cells that can be used as a transplant.

8

Three dimensional polyethersulphone scaffold for chondrocytes cultivation - the future supportive material for articular cartilage regeneration

Dudziński K., Chwojnowski A., Gutowska M., Płończak M., Czubak J., Łukowska E., Wojciechowski C.

Biocybernetics and Biomedical Engineering

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2010

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Vol. 30, no. 3

65-76

EN

The this paper method of obtaining broad-pore membranes for application as scaffolds for chondrocyte cultivation is described. These membranes were obtained from polyethersulfone. They are characterized by the presence of both macropores of relatively large diameter, as well as micropores. These membranes are intended first of all for use in cultivation of the cartilage cells (chondrocytes). The membranes are obtained by the phase inversion method followed by dissolving cellulose present in the membrane. Cellulose is a macropore precursor. Cellulose is dissolved by means of a copper hydroxide ammonia complex. The membranes obtained are not cyto-toxic. The culture of chondrocytes derived from White New Zeeland breed rabbits developed very well on these membranes. The cell cultures were studied by observation under an optical microscope and scanning electron microscope. The protein mass increase on the membrane was determined by flame analysis. The results of these experiments did not show any negative effects of the membranes on the cell culture. Just the opposite, the cartilage cells development on the membranes proceeded very well. The results obtained show that the membrane developed is a very good scaffold for cell cultivation.

9

Polysulphone and polyethersulphone hollow fiber membranes with developed inner surface as material for bio-medical applications

Chwojnowski A., Wojciechowski C., Dudziński K., Łukowska E.

Biocybernetics and Biomedical Engineering

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2009

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Vol. 29, no. 3

47-59

EN

A method of obtaining hollow fibers with developed internal surface has been elaborated. As materials were selected synthetic polymers, namely polysulphone Udel P-1700 and polyethersulphone Ultrason E2020P. This method enables the obtaining of such membranes by means of a spinneret with smooth walls and the installation for spinning hollow fibers. A mechanism of the formation of corrugations on the membrane internal surface has been proposed. The effect of spinning parameters on membrane formation has been described. An explanation of the reasons of formation of defects on the external skin layer has been proposed.

10

Influence of changes in composition of the membrane-forming solution on the structure of alginate-polyethersulfone microcapsules

Kupikowska B., Lewińska D., Dudziński K., Jankowska-Śliwińska J., Grzeczkowicz M., Wojciechowski C., Chwojnowski A.

Biocybernetics and Biomedical Engineering

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2009

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Vol. 29, no. 3

61-69

EN

The aim of this study was to evaluate the effects of changes in composition of the membrane-forming solution on the structure of alginate-polyethersulfone microcapsules as determined by optical microscopy and scanning electron microscopy. The microcapsules were produced from 4 solutions of different concentrations and molecular weights of synthetic polymer (polyethersulfone, PES) and porophore (polyvinylpyrrolidone, PVP). The composition of the membrane-forming solution strongly affected the structure of microcapsules. An increase in PES concentration caused a decrease in the membrane thickness. The inner and outer layers of the membrane became thinner and denser, while the pores of the middle finger-like zone turned into more regular, channel-like structures. The size of the pores was not directly affected by the molecular weight of porophore, however, an increase in its concentration resulted in formation of the larger inner surface pores, but the smaller outer surface pores.

11

A New Polymeric Support for Enzyme Immobilization for Biomicroreactors

Łukowska E., Pijanowska D., Chwojnowski A.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 6

1265-1272

EN

Preparation of three kinds of the modified polyacrylonitrile supports for enzymes used in microreactors is described. The polyacrylonitrile supports were produced using the phase inversion method, with dimethylformamide as a solvent. For conversion of the cyano groups into the carboxylic ones, the raw supports were treated with sodium hydroxide or, alternatively using a new method, with ammonium persulfate. The modified supports were used for urease immobilization. The comparison of the immobilization effectiveness and activity of the immobilized and free enzyme is presented. The effectiveness of urease immobilization was evaluated by two methods, spectrophotometric and potentiometric with use of the flow-through microreactor. It was stated that the two-layer structure films with the polyvinylpyrrolidone, as well as using of the ammonium persulfate for surface modification, made a significant improvement in efficiency of the enzyme immobilization.

12

Repair of articular cartilage full thickness defects with cultured chondrocytes placed on polysulphonic membrane - experimental studies in rabbits

Płończak M., Czubak J., Hoser G., Chwojnowski A., Kawiak J., Dudziński K., Czumińska K.

Biocybernetics and Biomedical Engineering

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2008

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Vol. 28, no. 2

87-93

EN

Autologous osteochondral transplantation is one of the methods. that can be used to create hyaline or hyaline - like repair in the defect area. The purpose of the present study was to repair the full - thickness articular cartilage defects in nine rabbits' knee joints with autologous cultured chondrocytes. An articular cartilage defect was created on the patellar groove of the femur. The defect was filled with the chondrocytes cultured in vitro and placed into the knee on a polysulphonic membrane. 8 weeks after the operation the reparative tissue was analyzed macroscopically and histologically. The surfaces of the reparative tissue were smooth, and the defects were filled with mature hyaline cartilage in five cases. In two cases the reparative hyaline cartilage was immature and there was worse integration of the grafted tissue into the adjacent normal cartilage. The surface of the grafted area was irregular, the reparative tissue was desintegrated and incompletely differentiated. The results suggest that transplantation of the autologous chondrocytes cultured in vitro and placed into the knee on the polysulphonic membrane is effective in repairing of the articular cartilage defect.

13

Obiektywny odczyt suchych testów

Chwojnowski A.

Elektronika : konstrukcje, technologie, zastosowania

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2005

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Vol. 46, nr 12

83-87

PL

Omówiono trzy podstawowe metody instrumentalnego odczytu suchych testów. Zaprezentowano zasady działania i przykłady podstawowych rozwiązań wykorzystywanych w praktyce do ustalania zależności: sygnał - stężenie analitu. Pokazano to na przykładach dostępnych aparatów do odczytu testów. Podano również wytłumaczenie dysproporcji w stosowaniu różnych metod odczytu.

EN

Three basic method instrumental method of dry tests reading are discussed in these paper. Principles of test reader actions and examples of basic usage in practical construction were described. Dependence signal - analyte concentration was shown on the examples of apparatus for test reading commercially available. Disproportions of apply different reading methods was explained either.

14

Fast tests in the service of a human being's environment

Chwojnowski A.

Chemia i Inżynieria Ekologiczna

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2004

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Vol. 11, nr 11

1149-1166

EN

A brief description of the design of basic fast tests bas been presented with particular consideration of dry tests. Basic methods of reading dry tests, both subjective and objective ones have been also described. Examples of applying fast tests for carrying out analysis under different conditions and in analytical matrices of various origin such as flood waters, mine waters, well water and natural water-courses and reservoirs, industrial wastewaters, fruit juices and finally milk have been also described. A good correlation of measurements carried out by means of the tests with the results of classical colorimetric measurements bas been shown. The high utility of fast tests for detecting and determining a number of ions and compounds where the rate of measurement is much more important than a very high precision bas been shown for selected examples. The examples presented have shown the usefulness of dry tests in various fields of a human being environment protection.

PL

W skrócie opisano podstawy budowy szybkich testów ze szczególnym uwzględnieniem testów suchych. Opisano również podstawowe sposoby odczytu testów suchych zarówno subiektywne, jak i obiektywne. Opisane zostały również przykłady wykorzystania szybkich testów do wykonywania analiz w różnych warunkach i w matrycach analitycznych bardzo różnego pochodzenia, takich jak: wody powodziowe, wody kopalniane, woda ze studni i naturalnych cieków i zbiorników, ścieki przemysłowe, soki owocowe i wreszcie mleko. Pokazano dobrą zgodność pomiarów wykonanych za pomocą testów z wynikami klasycznych pomiarów kolorymetrycznych. Na wybranych przykładach wykazano bardzo dużą użyteczność szybkich testów do wykrywania i oznaczania szeregu jonów i związków, gdzie ważniejsza jest szybkość pomiaru od bardzo dużej dokładności. Zaprezentowane przykłady pokazują przydatność szybkich testów w różnych dziedzinach ochrony środowiska człowieka.

15

Polypropylene surface modified hollow fibers for immunoisolation of cells

Granicka L. H., Chwojnowski A., Kawiak J.

Biocybernetics and Biomedical Engineering

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2004

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Vol. 24, no. 2

59-67

EN

Membranes preventing the tissue overgrowth as well as toxic influence of the environment on cells encapsulated within them were elaborated. The permiselective polypropylene hollow fibers were modified using different methods of silanization, and the effect of silanization on the membrane transport properties as well as on the tissue overgrowth was assessed, in the light of their perspective application in encapsulation of the cells. The membrane's pressure silanization has been found to result in obtaining membranes allowing to decrease and/ or delimit the diffusive transport through the membrane of large solutes without a simultaneous transport change for small solutes. The applied different types of membrane's silanization allowed to avoid a massive tissue overgrowth during the implantation. The membranes have been found to comply with the requirements for membranes applied in immunoisolation.

16

Zastosowanie polisulfonóow i polieterosulfonów do wytwarzania suchych testów

Dudziński K., Chwojnowski A., Łukowska E.

Zeszyty Naukowe. Inżynieria Środowiska / Politechnika Śląska

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2002

|

z. 47

13-18

PL

Otrzymano membrany z roztworów polisulfonów i polieterosulfonów używając N,N-dimetyloformamid jako rozpuszczalnika i polivinylopirolidonu jako poroforu. Membrany żelowano w wodzie dejonizowanej. Badania właściwości membran wykonano pod kątem ich późniejszego zastosowania do wytwarzania suchych testów do oznaczania witaminy C w sokach owocowych.

EN

Membranes of polysulfone and polyethersulfone were prepared from mixtures containing N,N-dimethylformamide as solvent and polyvinylpirollidone as additive. Water was used as non-solvent. Membranes assessment were made at an angle of its later applications in dry tests for vitamin C determination in fruit juices.

17

Wykorzystanie membran półprzepuszczalnych w suchych testach

Chwojnowski A., Łukowska E., Dudziński K.

Zeszyty Naukowe. Inżynieria Środowiska / Politechnika Śląska

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2002

|

z. 46

453-460

PL

W artykule tym przedstawione zostały sposoby wykorzystywania membran półprzepuszczalnych w różnych typach suchych testów. Pokazano przykłady testów do pełnej krwi. W zależności od analizowanego roztworu i zastosowanej techniki oznaczeń pokazane zostały różne sposoby wykorzystania membran.

EN

Different applications of semipermeable membranes in dry tests were shown in these papers. The examples of dry tests for whole blood described. Various methods of membranes application were shown in different technique of analysis in tests.

18

Badanie wpływu silanizacji na własności transportowe membran do immunoizolacji

Granicka L., Kaczmarek-Baranek Ż., Chwojnowski A., Kawiak J.

Zeszyty Naukowe. Inżynieria Środowiska / Politechnika Śląska

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2002

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z. 47

37-44

PL

Modyfikowano powierzchnię polipropylenowych, półprzepuszczalnych membran kapilarnych przy zastosowaniu różnych sposobów silanizacji, badając wpływ pokrywania powierzchni membran na ich własności transportowe z punktu widzenia przyszłych zastosowań in vivo. Badano też obrastanie tkanką łączną membran modyfikowanych różnymi sposobami we wszczepach in vivo. Stwierdzono, że badane membrany spełniają wymogi membran do immunoizolacji komórek.

EN

The permiselective polypropylene hollow fiber's surface was modified using different ways of silanization and the influence of silanization on membrane transport properties was assessed. The tissue overgrowth of different modified membranes was evaluated in vivo. It was found that the membranes comply with the requirements for membranes applied for immunoisolation.

19

Suchy test do szybkiego oznaczania stężenia salicylanów w osoczu

Łukowska E., Dudziński K., Chwojnowski A., Ulanowski W.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2002

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Vol. 8, nr 1-2

1-4

PL

Przedstawiono suchy test do oznaczania stężenia salicylanów w osoczu. W teście wykorzystuje się reakcję kompleksowania salicylanów jonami żelaza (III). Dodatek chlorku rtęci wypierając salicylany z ich kompleksów z białkami krwi, pozwala oznaczyć sumę wszystkich salicylanów7 w osoczu. Dobrano polimer ochronny, który zabezpiecza test przed pyleniem i uwalnianiem toksycznego chlorku rtęci (II). Test został przebadam na wodnych roztworach wzorcowych wykonanych w laboratorium, a także na roztworach soli fizjologicznej, wodnych roztworach albuminy oraz na osoczu otrzymanym ze świeżej krwi bydlęcej.

EN

A quick and easy dry test for salicylates determination in serum has been presented. A complexing reaction between salicylates and iron nitrate has been adapted for the test. Addition of mercury chloride causes displacing of salicylates from their complexes with blood's proteins and thus determination of total volume of salicylates in blood's plasma is possible. A protective polymer has been selected for protection the test from dusting and emission of the toxic mercury (II) chloride. Tests on the standard water solutions, prepared in the laboratory, as well as on the physiological salt solutions, water solutions of albuminę and serum from the fresh cattle blood have been carried out.

20

Methods determinations of ascorbic acids (vitamin C) in biological fluids

Chwojnowski A., Chwojnowska Z., Łukowska E., Dudziński K.

Biocybernetics and Biomedical Engineering

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2001

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Vol. 21, no. 4

121-138

EN

Selected methods of determination of ascorbic acids in biological fluids are shown in this paper. Application of three reactions for the four-field dry test construction is presented. This test, developed by the authors is designed for vitamin C determination in juices. Examples of determination are shown. The method of approximate assessment of vitamin C in human diet such as a diet history method, food frequency questionnaire method, food records method and the 24 hours recall method are described in short. The results of estimated determinations of vitamin C content and percentage of realisation of recommended dietary allowances in daily diet are presented.

PL

W artykule pokazano wybrane metody oznaczania kwasu askorbinowego w płynach biologicznych. Przedstawiono również zastosowanie trzech reakcji barwnych do opracowanego przez autorów tego artykułu czteropolowych testów do oznaczania witaminy C w sokach, razem z przykładowymi wynikami oznaczeń. Opisano również metody szacunkowego określania zawartości witaminy C w diecie za pomocą metod takich jak historia żywienia, metoda częstotliwości spożycia, metoda zapisu spożycia i wywiad o spożyciu w ciągu ostatnich 24 godzin. Podano również wyniki takich oznaczeń razem z odniesieniem do procentu realizacji normy w dobowym spożyciu.