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1

Influence of silver-containing filler on antibacterial properties of experimental resin composites against Enterococcus faecalis

Adeeb S., Adeeb S., Chladek G., Pakieła W., Mertas A.

Journal of Achievements in Materials and Manufacturing Engineering

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2021

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Vol. 109, nr 2

59--67

EN

Purpose: The aim of the presented work was to investigate the impact of the S-P introduction into resin-based composites on their effectiveness against Enterococcus faecalis (E. faecalis). Design/methodology/approach: Seven experimental composites based on typical matrix were developed. Six of them contained a filler with antimicrobial properties (silver sodium hydrogen zirconium phosphate, S-P), while the control material contained only common reinforcement fillers. The materials were characterized in terms of the dispersion of the extender in the matrix and then subjected to microbiological tests. The efficiency in the reduction of E. faecalis in the microenvironment was tested. Findings: The composites show a satisfactory distribution of fillers and a high initial reduction of bacteria colonies for the tested strain of E. faecalis. The reduction in bacteria colonies achieved for S-P concentrations from 7% to 13% was similar (median value from 99.8 to 99.9%, when for control material and compound with 1% S-P the number of colonies increased compared to positive control. Research limitations/implications: Laboratory test results may differ from in vivo test performance. In addition, there are many models for conducting laboratory antimicrobial efficacy studies, the results of which are also varied. The cytotoxic tests, long-term investigations and in vivo experiments need to be performed in future experiments. Practical implications: E. faecalis is a Gram-positive bacterium that is commonly detected in persistent endodontic infections and may enter the root canal through the coronal part. Development of composites with antimicrobial properties against this bacterium is as important as obtaining efficacy against cariogenic bacteria. Originality/value: The antimicrobial effectiveness against E. faecalis of experimental composites with submicrometer-sized particles of S-P was not investigated until now.

2

The influence of silver nanoparticles introduced into RTV-silicone matrix on the activity against Streptococcus mutans

Chladek G., Mertas A., Krawczyk C., Stencel R., Jabłońska-Stencel E.

Archives of Materials Science and Engineering

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2016

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Vol. 78, nr 2

59--65

EN

Purpose: The silicone based room temperature vulcanized (RTV) polymers are commonly used materials for medicine, especially for dentures and maxillofacial prostheses. Unfortunately, the colonization of those materials by pathogenic microorganisms is wellknown problem related with their applications. The aim of presented study was to examine antibacterial properties of RTV silicone for dentistry modified with silver nanoparticles. Design/methodology/approach: The silver nanoparticles were introduced into twocomponent system silicone based materials. The presence of silver nanoparticles was investigated with scanning electron microscope (SEM). The antibacterial activity against Streptococcus mutans was determined. The result were statistically analysed with a Statistica 12.5 software and non-parametric Kruskal-Wallis test (α = 0.05). Findings: The silver nanoparticles introduction into RTV - silicone allowed to enhance the antimicrobial resistance against standard strain of Streptococcus mutans. Research limitations/implications: In this research only Streptococcus mutans bacterium strain was used. In future activity of presented materials against other pathogenic bacteria living in oral cavity should be determined. Additionally long term investigation should be prepared. Practical implications: The colonization of dental materials with pathogenic bacteria and fungus is one of the most important and still unresolved problems related to exposition on oral environment. The low microbiological resistance of RTV-silicones and antimicrobial potential of silver were reported in numerous studies. The gram-positive Streptococcus mutans is commonly found in the human oral cavity and it is an important factor to tooth decay. Originality/value: The resistance against Streptococcus mutans of modified material was enhanced. The investigated materials could be a potential factor a potential conducive to reducing the risk of oral cavity infections.

3

Biodegradable and antimicrobial polycaprolactone nanofibers with and without silver precipitates

Dobrzański L. A., Hudecki A., Chladek G., Król W., Mertas A.

Archives of Materials Science and Engineering

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2015

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Vol. 76, nr 1

5--26

EN

Purpose: The purpose of the paper is to present the results of own researches, including the study of the structure and the properties of new obtained single- and doublecomponent polycaprolactone polymer nanofibers as well as of composite nanofibers with and without silver precipitates produced by electrospinning including the results of biological research, proving the usefulness of the newly developed nano-engineering materials and their applicability in regenerative medicine, as well as tissue engineering. Design/methodology/approach: On the basis of the data available from the fundamental literature and based on the criteria of potential and attractiveness, polycaprolactone was selected for research from among a number of polymer materials, using a method of procedural benchmarking and weighted scores. The obtained nanomaterials undergone the following examinations to confirm the assumed aim of the work: infrared spectroscopy FTIR, Wide-angle X-ray scattering (WAXS), BET, Langmuir specific surface area and DTF porosity assessed with the gas adsorption method, in a transmission electron microscope (TEM), a scanning electron microscope (SEM), a fluorescence microscope, antibacterialness and antifungalness investigations and examinations of biological properties in vitro. Findings: The applicability of polymer fibers in medicine depends on biocompatibility and non-toxicity of the applied material, which is influenced by the chemical purity of the materials applied and the toxicity of the input solvents. The potential toxicity of nanofibers should therefore be eliminated, starting with selection of materials used for obtaining solutions. Many other factors fundamental for the quality and properties of polycaprolactone nanofibers need to be taken into account to create single- and doublecomponent and composite nanofibers. Practical implications: The obtained composite materials, due to their non-toxicity resulting from the components applied, including solvents, bacteriocidity and bioactivity, may find their applications in tissue engineering as membranes in controlled regeneration of bone tissue, as carriers of medicinal agents in bone surgery, as implantable surgical meshes and as scaffolds for a tissue culture. In turn, the composite core-shell nanofibers, by combining the antibacterial properties of the coating with bioactive properties of the core, are attractive materials for three-dimensional tissue scaffold. Such materials can be used as a carrier of medicine, a treatment of hard healing wounds, invasive surgery, neurosurgery, as substrate for the culturing of a retina, material to reconstruct nerves and in dentistry or oncology, to replace the natural tissue removed because of a cancer with the possibility of applying a therapeutic agent, e.g., an antibiotic or a medicine used in cancer therapies, released after the dissolution of the coating of nanofibers. Originality/value: The present paper is the original report from a personal own research and explains the concept and scope of own research of a new obtained single- and doublecomponent polycaprolactone polymer nanofibers as well as of composite nanofibers produced by electrospinning for application in regenerative medicine, the presentation of technological conditions and methodology of own research into polymer nanofibers, and above all very detailed description of the results of own investigations

4

Poly(lactide-co-glycolide) composites containing antibacterial silver nanoparticles : in vitro preliminary study

Ziąbka M., Mertas A., Król W.

Composites Theory and Practice

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2014

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R. 14, nr 3

155--162

EN

This work concerns the biological and morphological assessment of poly(lactide-co-glycolide)/silver nanoparticle (nAg) composites prepared by the slip-casting method. Due to the significance of the bactericidal properties of such materials, antibacterial activity against Gram-positive - Staphylococcus aureusand Gram-negative - Escherichia coliwas evaluated by means of the surface deposition method. By inductively coupled plasma mass spectrometry (ICP-MS), it was possible to evaluate the amount of released silver ions and to determine their impact on the surrounding environment of bacteria. The material microstructure and dispersion of the modifier phase were estimated by using electron scanning microscopy with elemental analysis in micro-areas (SEM+EDS). The roughness and Theta angle measurements allowed us to define the surface character of the investigated materials. The tests of antibacterial efficacy proved that nanosilver-modified composites have bactericidal activity against the tested bacteria. The antibacterial efficacy of the tested materials depends on the amount of modifier phase (nAg). Along with an increasing volume fraction of modification phase, a different degree of the homogenization process was observed as well as a reduction in composite homogenization, a roughness increase and Theta angle decrease. At the same time, the composites showed higher wettability. Spectrometric analysis showed that the amount of released silver ions depends on the amount of nanoparticles present in the polymer matrix.

PL

W pracy przedstawiono ocenę morfologiczną i biologiczną kompozytów polilaktyd-ko-glikolid/nanocząstki srebra (nAg) otrzymanych w procesie odlewania folii. Materiały kompozytowe oraz polimer w czystej postaci poddane zostały testom oceny aktywności przeciwbakteryjnej. Skuteczność bakteriobójcza została oceniona wobec wzorcowych szczepów Gram-dodatnich bakterii Staphylococcus aureus oraz Gram-ujemnych bakterii Escherichia coli, wykorzystując w tym celu technikę osadzania powierzchniowego. Za pomocą techniki elektronowej mikroskopii skaningowej (SEM) oraz spektroskopii z dyspersją energii (EDS) przeprowadzono ocenę mikrostruktury oraz stopnia dyspersji fazy modyfikującej w matrycy polimerowej. Dzięki przeprowadzonym pomiarom profilometrycznym oraz kąta zwilżania określono charakter powierzchni badanych materiałów. Ilość uwolnionych jonów srebra oznaczono techniką spektrometrii mas ze wzbudzeniem w plazmie indukcyjnie sprzężonej (ICP-MS). Antybakteryjne działanie materiałów korelowano z ilością uwolnionych do otoczenia jonów srebra. Na podstawie wyników przeprowadzonych testów i obserwacji wykazano, że kompozyty polimerowe modyfikowane nanosrebrem wykazują działanie bakteriobójcze wobec wzorcowych szczepów Gram-dodatnich bakterii Staphylococcus aureus oraz Gram-ujemnych bakterii Escherichia coli. Skuteczność przeciwbakteryjnego działania badanych materiałów kompozytowych uzależniona była od ilości dodatku antybakteryjnego (nAg). Wraz z rosnącym udziałem fazy modyfikującej obserwowano niższy stopień homogenizacji kompozytów, wzrost chropowatości i spadek kąta zwilżania, ale tym samym kompozyty wykazywały wyższą zwilżalność. Największą skutecznością działania przeciwbakteryjnego wobec bakterii Gram-dodatnich i Gram-ujemnych wykazywały się kompozyty z dodatkiem trzech procent wagowych nanosrebra.

5

Surface properties and antimicrobial activity of composite nanofibers of polycaprolactone with silver precipitations

Dobrzański L., Hudecki A., Chladek G., Król W., Mertas A.

Archives of Materials Science and Engineering

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2014

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Vol. 70, nr 2

53--60

EN

Purpose: The purpose of the article is to investigate the structure and antimicrobial properties of composite nanofibers with silver particles precipitated onto the nanofibers surface. Design/methodology/approach: A solution was prepared in the first place made of the following solvents to fabricate antimicrobial composite nanofibers of polycaprolactone with silver precipitations: formic acid and acetic acid at a rate of 70:30. Then, silver nitrate was introduced into the fabricated solution of the solvents and it was subjected to the interaction of ultrasounds, and after 10 minutes polycaprolactone was added to the solution, and then the solution was mixed for 12 hours and a solution was obtained with a 10% concentration and the mass fraction of 0, 1, 3 and 5% of silver nitrate additives. The solution was forced into a positive voltage electrode placed above a negative voltage electrode; the solution was then subjected to the activity of a strong electrostatic field transforming the solution into micro- and nanofibers. After electrospinning, the fibers obtained underwent the activity of a 2% ascorbic acid solution, by means of which silver was precipitated on the nanofibers surface. Viscosity and electrical conductivity tests were performed of single-component and double-component solutions, of the fibers’ structure in a transmission electron microscope, of the BET, Langmuir specific surface area and DTF porosity with the method of gas adsorption and antimicrobial activity of the nanocomposites produced on the nanocomposites on following bacteria: Staphylococcus aureus, Escherichia coli, Candida albicans. Findings: The use of a formic acid and acetic acid solution at a rate of 70:30 for preparation of a polycaprolactone solution for its electrospinning enables to obtain a non-toxic and fully biodegradable polymer nanofibers of polycaprolactone with PCL/Ag silver precipitations possessing high antimicrobial performance against Gram+, Gram- bacteria and fungi. Practical implications: Antimicrobial composite nanofibers with silver nanoparticles precipitated onto the nanofibers surface can be applied in biodegradable antiseptic dressings in the form of mats or other textiles containing polymer nanofibers of polycaprolactone with PCL/Ag silver precipitations obtained as a result of electrospinning. Originality/value: The research outcomes confirm that it is feasible to manufacture polycaprolactone nanofibers with PCL/Ag silver precipitations possessing high antimicrobial performance against Gram+, Gram- bacteria and fungi.

6

Zastosowanie numerycznej mechaniki płynów (CFD) w procesie projektowym

Mertas A., Jażdżyk P.

Wiadomości Projektanta Budownictwa

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2013

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nr 1

17--20

7

Aspekty immunologiczne terapii fotodynamicznej

Kawczyk-Krupka A., Czuba Z., Latos W., Mertas A., Król W., Simon-Sieroń M., Sieroń A.

Journal of Ecology and Health

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2010

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R. 14, nr 6

284-290

PL

Terapia fotodynamiczna (photodynamic therapy - PDT) jest metodą leczenia wybranych (przede wszystkim wczesnych) nowotworów i stanów przednowotworowych. Istotą tej metody jest selektywne niszczenie zmienionych chorobowo tkanek poprzez zadziałanie na nie światła laserowego o ściśle określonej długości fali. Zjawisko to umożliwia substancja - fotouczulacz, wychwytywana przez chorobowo zmienioną tkankę. Standardowo stosowanymi fouczulaczami są porfiryny, które są komponentą hemoglobiny. Działanie fotodynamiczne wywołuje trzy typy reakcji w naświetlanej tkance: bezpośredni efekt cytotoksyczny, pośredni efekt cytotoksyczny przez okluzję naczyń krwionośnych oraz wtórne działanie immunostymulujące i prozapalne. Spośród wymienionych sposobów działania, efekt immunostymulujący wydaje się być unikalny, zważywszy, że zarówno chemio- jak i radioterapia powodują upośledzenie funkcji układu immunologicznego. Wiele prac doświadczalnych wykazało, iż w trakcie terapii fotodynamicznej dochodzi do mobilizacji komórek immunokompetentnych: nacieku limfocytów, neutrofili, makrofagów, co wskazuje na aktywację procesu zapalnego. Mediatorami tego procesu są substancje wazoaktywne, składniki C3 dopełniacza, białka ostrej fazy, proteinazy, peroksydazy, reaktywne formy tlenu, cytokiny, czynniki wzrostu oraz inne substancje biorące udział w odpowiedzi immunologicznej. Podkreśla się, iż immunomodulacyjny efekt terapii fotodynamicznej związany jest także z wpływem na angiogenezę i aktywność metastatyczną komórek nowotworowych.

EN

Photodynamic therapy (PDT) is a well-known method for the selective, non-invasive and effective treatment of precancerous and cancerous lesions due to the activation of photobiochemical processes that cause cytotoxicity. PDT is based on mutual reactions between laser irradiation and photosensitizers that accumulate in tissues and result in selective damage of pathological tissues. The anticancer effect of PDT is due to three main mechanisms. First, PDT is cytotoxic, with both necrotic and apoptotic effects. Second, PDT leads to the occlusion of blood and lymphatic vessels of the tumor. Third, PDT is associated with the modulation of immune and inflammatory responses. In addition to these mechanisms of cell death, there is a variety of events that occur during PDT that lead to and magnify the inactivation of tumor cells. Many studies have reported the infiltration of lymphocytes, neutrophils and macrophages into PDT-treated tissue, indicating activation of the immune response. The inflammatory process is mediated by factors such as vasoactive substances, components of the complement and clotting cascades, acute phase proteins, proteinases, peroxidases, reactive oxygen species, leukocyte chemoattractants, cytokines, growth factors and other immunoregulators. It is possible that immunomodulatory mechanisms of PDT could also influence angiogenesis and the invasiveness of tumor cells.

8

Wstępna ocena biologiczna kompozytów polioksymetylen/nanosrebro

Ziąbka M., Mertas A., Król W., Chłopek J.

Engineering of Biomaterials

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2009

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Vol. 12, no. 89-91

196--199

PL

W pracy przedstawiono ocenę morfologiczną i biologiczną kompozytu polioksymetylen/nanocząstki srebra otrzymanego w procesie wytłaczania i wtrysku. Badania komórkowe przeprowadzono metodą bezpośredniego kontaktu. Na podstawie zmian w morfologii komórek (fibroblasty mysie 3T3 Balb), ich przeżywalności i zdolności do proliferacji oceniono stopień toksyczności materiałów. Wykorzystując tech-nikę osadzania powierzchniowego przeprowadzono badania oceny aktywności przeciwbakteryjnej wobec bakterii Gram-dodatnich – Staphyloccocus aureus i Gram-ujemnych – Escherichia coli. Przeprowadzone badania komórkowe pokazały, że zarówno czysty polioksymetylen jak i modyfikowany nanosrebrem nie posiadają działania cytotoksycznego. Testy aktywności bakteriobójczej dowiodły natomiast, że materiały modyfikowane nanosrebrem wykazują niewielkie działanie bakteriobójcze wobec badanych bakterii.

EN

This paper presents morphological and biological evaluation of polyoxymethylene / silver nanoparticle composite produced in extrusion and injection moulding. Studies of cellular interactions were performed using direct contact method. The toxicity rate of materials was assessed on the basis of changes in cellular morphology (mouse fibroblasts 3T3 Balb), cell survivability and proliferation rates. Antibacterial activity against Gram-positive – Staphyloccocus aureus and Gram-negative – Escherichia coli bacteria was evaluated by means of surface deposition method. In studies of cellular interactions, both, pure polyoxy-methylene and nanosilver-modified polyoxymethylene produced no cytotoxicity. Also, nanosilver-modified materials showed slight bactericidal activity against the tested bacteria.

9

Pozaustrojowe badania nad toksycznym oddziaływaniem kopolimeru PLGA z dodatkiem hydroksyapatytu na ludzkie osteoblasty linii hFOB 1.19

Cieślik M., Mertas A., Morawska-Chochół A., Orlicki R., Owczarek A., Król W.

Engineering of Biomaterials

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2009

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Vol. 12, no. 89-91

97--102

PL

W celu biologicznej oceny w warunkach in vitro kopolimeru glikolidu z laktydem z dodatkiem hydroksyapatytu (PLGA+HA) dokonano oceny stopnia jego cytotoksyczności względem ludzkich osteoblastów linii hFOB 1.19. Wykonano pomiar aktywności dehydrogenazy mitochondrialnej (test MTT) oraz dehydrogenazy mleczanowej (test LDH) po 24 i 48 godzinach kontaktu komórek z ekstraktem uzyskanym poprzez 8-dniową inkubację kompozytu w medium do hodowli osteoblastów. Kontaktowano ponadto badany materiał bezpośrednio z komórkami kościotwórczymi, a stopień cytotoksyczności oceniano po 24, 48 i 72 godzinach stosując w tym celu test LDH. W obu metodach badany materiał nie wpływał w sposób toksyczny na ludzkie osteoblasty.

EN

In order to evaluate lactide-glycolide co-polymer with admixture of hydroxyapatite (PLGA+HA) from biological point of view in vitro conditions, its level of toxicity for human osteoblasts line hFOB 1.19 was assessed. The activity of mitochondrial dehydrogenase and lactate dehydrogenase was measured (MTT test and LDH test respectively) after 24 and 48 hours of the cells’ contact with the extract obtained through 8-day incubation of the composite in osteoblasts cultivation medium. Apart from that the material examined was contacted with bone-forming cells and its degree of toxicity was assessed after 24, 48 and 72 hours using LDH test. In both methods the material under examination did not have any toxic influence upon human osteoblasts.

10

Wpływ wzmocnionego włóknami węglowymi kopolimeru glokolidu z laktydem na odpowiedź komórkową

Cieślik M., Król W., Mertas A., Morawska-Chochół A., Ziąbka M., Chłopek J.

Engineering of Biomaterials

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2008

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Vol. 11, no. 81-84

40--44

PL

W pracy dokonano oceny cytotoksycznego wpływu wzmocnionego włóknami węglowymi kopolimeru glikolidu z laktydem (PLGA+CF) na ludzkie osteoblasty linii hFOB 1.19. Przeprowadzono w tym celu pomiar aktywności dehydrogenazy mitochondrialnej metodą MTT oraz dehydrogenazy mleczanowej (test LDH) w warunkach in vitro. Oba testy nie wykazały toksycznego działania badanego kompozytu na ludzkie komórki kościotwórcze.

EN

This work evaluates the cytotoxic impact of poly-lactide-co-glycolide reinforced with carbon fibres (PLGA+CF) on the hFOB 1.19 human osteoblastic cell line. To this end the levels of miochondrial dehydrogenase (MTT method) and lactate dehydrogenase (LDH test) were measured in vitro. Neither test showed a toxic effect of the studied composite on the human osteogenic cells.

11

Ocena cytotoksyczności kopolimeru glikolidu z laktydem (PLGA) w warunkach in vitro

Cieślik M., Król W., Mertas A., Morawska-Chochół A., Ziąbka M., Chłopek J.

Engineering of Biomaterials

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2008

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Vol. 11, no. 81-84

35--39

PL

Celem pracy była ocena in vitro cytotoksycznego działania bioresorbowalnego kopolimeru glikolidu z laktydem (PLGA) na ludzkie osteoblasty linii hFOB 1.19 poprzez pomiar aktywności dehydrogenazy mitochondrialnej (test MTT) oraz dehydrogenazy mleczanowej (test LDH). Do badań użyto ekstrakt uzyskany po 8 dniach inkubacji kopolimeru PLGA w medium wykorzystywanym do hodowli osteoblastów. Ekstrakt ten następnie kontaktowano przez 24 oraz 48 godziny z zaadherowanymi do dna naczynia hodowlanego osteoblastami. Po upływie założonego czasu inkubacji zarówno test MTT, jak i test LDH nie wykazał cytotoksycznego działania kopolimeru PLGA na ludzkie komórki kościotwórcze.

EN

The aim of the work was to evaluate in vitro the cytotoxic effect of bioresorbable polylactide-co-glycolide (PLGA) on the hFOB 1.19 human osteoblastic cell line by measuring the activity of mitochondrial dehydrogenase (MTT test) and lactate dehydrogenase (LDH test). The research made use of an extract obtained after 8 days of PLGA incubation in a medium used for osteoblast culturing. The extract was then brought into contact with osteoblasts adhered to the bottom of the culture vessel for 24 and 48 hours. After the set incubation time neither the MTT test nor the LDH test showed a cytotoxic effect of PLGA on human osteogenic cells.