Probiotics are life microorganisms that, after administration in gastrointestinal (GI) tract, excert positive effects on host’s health. Host reaction to probiotic administration largely depands on ...ability of bacteria to closely interact with epithelial cells of GI mucosa. On the other hand, considering the unknown antigenic nature of administered bacteria, in immune-compromised host there is a risk of immune reaction of gut tissue which could lead to disturbance of mucosal barrier integrity and chronic inflammation in GI tract. The aim of the study was to examine the effects of the strain Lactobacillus fermentum BGHI14, which is alochtonous to GI tract of rats, after peroral administration in healthy rats and in rats with TNBS (trinitrobenzenesulfonate)-induced colitis. Methodologically, following parameters were examined in experiments: body masses of rats and expression of mRNA of inflammatory cytokines (IL-1β, TNFα, IL-17F), as well as markers of cellular stress (HSP70) and barrier integrity maintenanace (TJP1); next histological and biochemical analyses and microflora profiling were performed. Results of the study indicated immune-stimulating effects of BGHI14 in colon tissue after administration in GI tract of healthy rats in first 16 days of peroral treatment of rats. Although, histologically, with prolongation of BGHI14 treatment of rats for next 12 days, immune reaction in colon tissue had retreated, mRNA levels of proinflammatory IL-1β and TNFα cytokines remained elevated which points to the risk of uncontrolled inflammation in the case of subsequent colon epithelial barrier damage. In research it was shown that after immunostimulation of colon tissue with BGHI14, in the case of colitis induction, but with sequel of treatment with bacteria, transcription of Hsp70 gene was induced, in early (48 h) as well as late (7 days) acute phase of colitis. The increase of Hsp70 gene transcription, according to histological and inflammatory markers, as well as body mass changes during the experiment, was not followed by positive action of the strain. On the other hand, the cessation of treatment with BGHI14 after colitis induction had led to less pronounced body mass decrease compared to control colitic rats, but without concomitant reduction in inflammatory scores in colon tissue, at least in late acute phase of disease (seven days from induction). Based on the above, it could be concluded that mechanisms of adaptive immunity including memory T-cells might had been activated during interaction of BGHI14 with healthy colon tissue and those systems were induced after the injury in the case of continuous presence of same bacterial antigen. Contrary, therapeutic treatment with BGHI14 had brought about the protection in late acute colitis phase according to body mass changes as well as indicators of mucosal barrier disruption. Obtained results implicate that use of immune-stimulating probiotics immediately after colon tissue damage would represent effective approach in treatment of bowel inflammatory diseases, though more detailed research is needed in this area. Considering the importance of interaction of bacteria with gut mucosa in achieving its probiotic potential, in current research mechanisms for improvement of potential probiotic lactobacilli binding to rat’s GI mucosa were tested. In this respect the effects of mucinbinding domain containing protein (MbpL) from strain Lactococcus lactis subsp. lactis BGKP1-20 in ability of bacterial host to bind to ileal and colonic mucosa in vivo and ex vivo, as well as in assays in vitro with isolated mucin and mucin-producing HT29-MTX colonic cells were tested. Aside from using the homologous host, for functional tests we have used potential probiotic strain Lactobacillus salivarius BGHO1. Results have demonstrated that the expression of MbpL protein was not sufficient for binding of BGHO1 to gut mucosa, although it influenced positively the binding of BGKP1-20 to pig gastric mucin and HT29-MTX cells in culture. It is possible that in lactococcal strain BGKP1-20, phenotypic effects of MucBP protein expression are more pronounced compared to BGHO1 strain, because of presence of other potential adhesion factors synthesized in lactobacilli strains. Simultanously, utillizing the same methodology, the role of aggregation factor AggL from BGKP1-20 in binding to GI tract mucosal surfaces was tested. Expression of aggregation factor is commonly correlated to enhanced affinity of bacterial host to GI mucosa. Our results have demonstrated that, although, by increasing surface hydrophobicity, in lactococcal strains it could contribute to binding to colonic surface, the expression of aggregation factor generally aggravates binding of bacteria to surfaces exposed to dynamic peristaltic contractions such as those present in ileum. That way strains expressing aggregation factor could facilitate removal of pathogens but without directly affecting the host’s immune system.
Probiotici predstavljaju žive mikroorganizme koji, nakon unošenja u gastrointestinalni (GI) trakt, ostvaruju pozitivne efekte na zdravlje domaćina. Reakcija domaćina na unos probiotika u velikoj meri zavisi od sposobnosti bliske interakcije bakterija sa epitelnim ćelijama GI mukoze. S druge strane, s obzirom na nepoznatu antigenu prirodu unetih bakterija, kod imunokompromitovanog domaćina je prisutan rizik od imunske reakcije crevnog tkiva što može da dovede do narušavanja integriteta mukozne barijere i hronične inflamacije u GI traktu. Cilj istraživanja bio je ispitivanje efekta soja Lactobacillus fermentum BGHI14, alohtonog za GI trakt pacova, nakon peroralnog unosa u zdrave pacove i u pacove sa kolitisom indukovanim TNBS-om (trinitrobenzensulfonat). Metodološki, u eksperimentima su praćeni: telesna masa pacova i ekspresija iRNK za parametre inflamacije (IL-1β, TNFα, IL-17F), pokazatelje ćelijskog stresa (HSP70) i parametre uključene u održavanje integriteta mukoze (TJP1); zatim su rađene histološke i biohemijske analize i analiza sastava crevne mikroflore. Rezultati istraživanja su pokazali imunostimulišuće delovanje soja BGHI14 na nivou tkiva kolona nakon unosa u GI trakt zdravih pacova u prvih 16 dana peroralnog tretmana pacova. Iako se, histološki, sa produžetkom tretmana pacova sojem BGHI14 tokom narednih 12 dana, imunska reakcija u tkivu kolona povukla, nivoi iRNK za proinflamatorne IL-1β i TNFα citokine ostali su povišeni što ukazuje na rizik od nekontrolisane inflamacije u slučaju naknadnog oštećenja epitelne barijere kolona. U istraživanju je pokazano da je nakon imunostimulacije tkiva kolona sojem BGHI14, u slučaju indukcije kolitisa, ali uz nastavak tretmana sojem BGHI14 došlo do indukcije transkripcije iRNK za HSP70 protein, kako u ranoj (48 h) tako i u kasnoj (7 dana) akutnoj fazi kolitisa. Povećanje transkripcije Hsp70 gena, sudeći po histološkim i inflamatornim pokazateljima, kao i promenama telesnih masa pacova tokom eksperimenta, nije bilo praćeno pozitivnim delovanjem soja. S druge strane, prestanak tretmana sojem BGHI14 nakon indukcije kolitisa doveo je do manje izraženog pada telesnih masa životinja u poređenju sa kontrolnim pacovima sa kolitisom, iako bez pratećeg smanjenja inflamatorne reakcije u tkivu kolona, bar u kasnoj akutnoj fazi bolesti (sedam dana od indukcije). Na osnovu opisanog može se zaključiti da su se u interakciji soja BGHI14 sa zdravim tkivom kolona aktivirali mehanizmi adaptivne imunosti u vidu memorijskih T-limfocita koji su indukovani nakon povrede u slučaju kontinuiranog prisustva istog bakterijskog antigena. Nasuprot, terapijski tretman pacova sojem BGHI14 doveo je do pozitivnog efekta u kasnoj akutnoj fazi kolitisa ocenjujući po promenama telesnih masa životinja kao i na osnovu parametara oštećenja mukozne barijere kolona. Dobijeni rezultati ukazuju da bi primena imunostimulišućih probiotika neposredno po nastanku oštećenja crevnog tkiva predstavljala efikasan pristup u lečenju inflamatornih oboljenja crevnog trakta, iako su na ovu temu potrebna dodatna istraživanja. S obzirom na značaj koji interakcija bakterija sa crevnom mukozom ima u ostvarivanju njihovog probiotičkog potencijala, u istraživanju su testirani mehanizmi kojima se može poboljšati vezivanje laktobacila kao potencijalnih probiotika za GI mukozu pacova. U tom smislu praćeni su efekti proteina sa mucin-vezujućim domenom (MbpL) poreklom iz soja Lactococcus lactis subsp. lactis BGKP1-20 na sposobnost vezivanja bakterijskog domaćina za mukozu ileuma i kolona u uslovima ex vivo i in vivo, kao i u in vitro esejima sa izolovanim želudačnim mucinom i mucin-produkujućim HT29-MTX ćelijama kolona. Osim homolognog domaćina, za funkcionalna ispitivanja korišćen je potencijalni probiotički soj Lactobacillus salivarius BGHO1. Rezultati su pokazali da eksprimirani MbpL protein nije bio dovoljan za vezivanje soja BGHO1 za crevnu mukozu, iako je pozitivno uticao na vezivanje BGKP1-20 soja za svinjski želudačni mucin i HT20-MTX ćelije u kulturi. Moguće je da je fenotipski efekat ekspresije MucBP proteina kod laktokokalnog BGKP1-20 soja veći u odnosu na BGHO1 soj, s obzirom na prisustvo drugih potencijalnih adhezivnih faktora koji se sintetišu u laktobacilima. Koristeći istu metodologiju testirana je uloga koju u vezivanju za mukozne površine GI trakta ostvaruje agregacioni faktor AggL poreklom iz soja BGKP1-20. Agregacioni faktor eksprimiran na površini bakterijskih ćelija često se dovodi u vezu sa povećanim afinitetom bakterijskog domaćina za GI mukozu. Naši rezultati su pokazali da, iako bi, povećanjem površinske hidrofobnosti mogao doprineti vezivanju za površinu kolona kod laktokokalnih sojeva sa niskom ukupnom hidrofobnošću površine, eksprimirani agregacioni faktor generalno otežava vezivanje bakterija za površine izložene dinamičkim peristaltičkim kontrakcijama kakva je u najvećoj meri površina ileuma. Na taj način bi sojevi koji sintetišu faktor agregacije mogli olakšati uklanjanje patogena ali bez sposobnosti ostvarivan
Lijepljenje je suvremena metoda spajanja dijelova koja ima značajne prednosti u usporedbi s mehaničkim metodama spajanja dijelova. U lijepljenim spojevima opterećenja se prenose cijelom površinom ...spoja, što osigurava veću otpornost na savijanje i vibracije nego pri mehaničkim spojevima.
U radu su prikazane teorijske osnove djelovanja kohezijskih i adhezijskih sila pri stvaranju lijepljenog spoja. U eksperimentalnom dijelu rada ispitivan je utjecaj parametara lijepljena na prekidnu silu lijepljenog spoja.
Cilj ovog rada je ispitati jačinu adheziije između poliuretanskog nanosa i podloge više naslojenih pletiva, te usto opisati svojstva poliuretana, te tehnološki proces nanošenja poluretana na pletivo. ...Ispitivana je adhezija četiri uzorka naslojenog pletiva. To su poliuretanom naslojeno glatko desno-lijevo pletivo, poliuretanom naslojeno kulirno interlok pletivo, poliuretanom naslojeno osnovino pletivo power – net, te poliuretanom naslojeno osnovino pletivo voile. Svaki uzorak podvrgnt je ispitivanju adhezije po propisanoj normi. Uzorak sa power-net pletenom podlogom pokazuje najjaču adheziju između nanosa i podloge, najviše istezanje, te najmanju anizotropiju izmjerenih sila i istezanja po redu i nizu pletiva, te ga se može preporučiti za izradu odjevnih predmeta.
CA125 antigen, a well known tumour marker for serous ovarian cancer, is an
extracellular part of the mucin 16 (MUC16) molecule. This antigen arises from
proteolytic degradation of MUC16, a type I ...transmembrane protein, expressed
in both embrional and adult tissue. The primary structure of MUC16 consists
of three characteristic parts: an N-terminal region and a series of tandem
repeats, which are located extracellularly, and a C-terminal region, which
consists of the transmembrane part and a short cytoplasmic tail. The
extracellular peptide is extensively glycosylated, and there is a potential
phosphorylation site in the intracellular chain. Phosphorylation is a signal
for proteolysis and release of the extracellular part of the molecule (CA125
antigen), which can be detected as such in various body fluids. The
biological role of MUC16/CA125 is not yet understood. Previous investigations
of MUC16 (membrane form) functions were generally based on in vitro cell
model systems of ovarian cancer, whereas published data on the activity of
CA125 antigen (soluble form) are very rare. The soluble form is a functional
analog and competitor to the membrane form, and, in the circulation, it first
contacts different types of normal or pathologically altered cells. However,
there is no experimental evidence on its possible impact on their adhesion
nor immunomodulatory properties. In this work, the modular organization of
human CA125 antigen was analyzed bioinformatically and glycobiochemically,
aiming at closer definition of the biological capacity and presentation of
this molecule in the context of the human interactome. As part of a strategy
to detect a possible biological role for MUC16/CA125, bioinformatics analysis
has never been used in studies of this antigen. In addition, in the context
of discrete biological functions, regardless of its great biomedical
importance, there are no experimental data on the interactions of MUC16/CA125
with specific classes of receptors on cells of the blood system. The modular
organization of MUC16/CA125, was analyzed in silico using data taken from the
UniProtKB database, which refers to a molecule isolated from the human
ovarian cancer cell line, OVCAR-3. Bioinformatic analysis included:
determination of homology (using BLAST, Basic Local Alignment Search Tool
Tool); investigation of patterns, structural motifs and conserved domains
(using databases such as Bgee: a database for Gene Expression and Gene
Ontology Evolution, CDD, ELM, BLOCKS, InterProScan and MyHits iProClass);
determination of physical and chemical properties, globularity and deviations
from the assumed tertiary structure (using ProtParam, ProtScale and GLOBPLOT
v2.3 tools); and function prediction using tools that employ several
programs: JAFA, ProtFun 2.2 and GeneOntology. Glycobiochemical analysis
comprised examination of the influence of CA125 on adhesion and aggregation
of erythrocytes, as well as on interactions with different types of leukocyte
lectins, namely siglecs sialic acid-binding immunogobulin (Ig)-like lectin
and C-type lectin-like receptors selectins, dendritic cell-specific
ICAM-3-grabbing non-integrin 1 (DC-SIGN) and macrophage mannose receptor
(MMR). The effect of CA125 antigen on human erythrocytes was determined
using solid phase tests and light microscopy. The interaction of CA125 with
leukocyte receptors was investigated employing lectin-blot and immunoblot, as
well as binding and inhibition solid phase assays. Cancer antigen isolated
from human pleural fluid (pfCA125) and pregnancy-associated antigen (pCA125)
were included in the glycobiochemical analysis in addition to antigen from
the human ovarian carcinoma cell line (clCA125). The results of in silico
analysis placed MUC16/CA125 in the context of modular proteins with an
annotated role in adhesion-related processes. They pointed to similarities
within extracellular serine/threonine rich regions of MUC16 to protein
sequences expressed in evolutionarily distant taxa. No relation to annotated
domains from available databases appeared, except for BLLF1, a multidomain
characteristic of virus envelope glycoproteins of the Herpesviridae family.
Bioinformatics analysis also pointed to a possible correlation between
functional activities, which are attributed to serine/threonine rich domains
of proteins identified in the studied taxa, and possible CA125 antigen
function. Based on these results, the role of CA125 antigen in adhesion
processes could involve interactions through conserved protein sequences
responsible for ion transport, and for interactions with sugar substrates.
Considering the mucin nature of CA125 antigen, as well as physiological
conditions in which its concentration in serum is increased, the effect of
this antigen on human erythrocytes was investigated in the first part of
glycobiochemical analysis. The results showed that pCA125 and pfCA125
moderately increased aggregation of erythrocytes, and successfully inhibited
their adhesion. In contrast, clCA125 showed little to no modulation of these
properties. The second part of the glycobiochemical analysis related to
interactions with leukocyte receptors. This showed that, as a ligand, CA125
may interact with different types of proteins that bind sialic acid. Siglecs
were found to have specific binding patterns, which more effectively
distinguished CA125 antigens of fetal from those of cancer origin, in
contrast to the binding patterns of sialic acid-specific plant lectins. The
most obvious difference was the ligand capacity of pCA125 antigen towards
siglec-7, expressed on dendritic cells, NK (natural killer cells), monocytes
and CD8+ T cells, and clCA125 towards siglec-9 and siglec-10 on B cells, NK
cells, monocytes, neutrophils and CD8+ T cells. Unlike siglecs, all three
investigated selectins: L-selectin, E-selectin and P-selectin, interacted in
a dose-dependent manner with pfCA125, and to a lesser extent with pCA125, but
not with clCA125. Moreover, P-selectin reacted at significantly lower
concentrations than L- or E-selectin. Thus, CA125 antigen would
preferentially interact with activated endothelial cells or platelets
expressing P-selectin, compared to cells expressing the other types of
selectin. The interaction of CA125 antigen and DC-SIGN, which is specific for
mannan, high-mannose glycans and glycans with terminal Lex / Ley / Lea / Leb
antigens was studied. DC-SIGN is expressed on dendritic cells (DC) and
recognized pCA125 and pfCA125 antigen. Inhibition of DC-SIGN binding to
pCA125 was dependent on the presence of mannose-rich glycans, in contrast to
the binding to pfCA125, which was not affected by the presence of N- or
O-linked glycans, all which can modify their discrete receptor functions.
Macrophage mannose receptor (MMR), which is expressed on macrophages and DC,
and which binds terminal mannose, fucose and sialyl Lex, did not react with
any of the tested CA125 antigens. C-type lectin-like receptors play an
important role in the immune system, mediating in cell-cell interactions,
i.e. contacts between leukocytes or between leukocytes and endothelium, and
in the binding of pathogens. Glycosylation changes in ligands for C-type
lectin-like receptors directly influence their activity and specificity and
have important effects on the development, survival and reactivity of cells
of the blood and immune systems. Based on the results of this study,
differences in the structure/glycosylation of CA125 antigens associated with
different physiological or pathological conditions, could alter their
influence on the human blood cells, and have important biomedical
implications in different microenvironments. Further insight into the nature
and mechanisms of CA125 multifunctionality requires an interdisciplinary
approach, based on complex interactions that are mediated by its different
structural domains.
CА125 antigen, poznat kao marker seroznog karcinoma ovarijuma, predstavlja
ekstracelularni deo mucina 16 (MUC16), koji nastaje njegovom proteolitičkom
degradacijom. МUC16 pripada grupi transmembranskih proteina tipa I, i
eksprimiran je u velikom broju embrionalnih, ali i adultnih tkiva. Njegovu
primarnu strukturu karakteriše prisustvo tri regiona: N-terminalni region i
region tandemskih ponovaka, koji su smešteni ekstracelularno, i C-terminalni
region, koji se sastoji od transmembranskog dela i kratkog citoplazmatskog
repa. Ekstracelularni region je intenzivno glikozilovan, a u intracelularnom
regionu se nalazi potencijalno mesto fosforilacije. Fosforilacija predstavlja
signal za proteolizu i oslobaĊanje ekstracelularnog dela molekula (СА125
antigen), koji se kao takav može detektovati u različitim telesnim
tečnostima. Biološka uloga MUC16/CA125, još uvek nije razjašnjena. Dosadašnja
ispitivanja funkcije MUC16 (membranska forma) su, uglavnom, bila bazirana na
in vitro model sistemu ćelija ovarijalnog karcinoma, dok su literaturni
podaci o aktivnosti CA125 antigena (solubilna forma) veoma retki. Solubilna
forma predstavlja funkcionalni analog i kompetitor membranskoj formi i, u
cirkulaciji, ona prva dospeva u kontakt sa različitim tipovima normalnih ili
patološki izmenjenih ćelija, ali ne postoje eksperimentalni dokazi o mogućem
uticaju na njihovu adhezivnost, kao i imunomodulatorna svojstva. U ovom radu
je ispitivana modularna organizacija MUC16/CA125 na bioinformatičkom i
glikobiohemijskom nivou, sa ciljem da se bliže definišu biološki kapacitet i
posebnosti prezentacije ovog molekula u kontekstu interaktoma čoveka.
Bioinformatička analiza, kao deo strategije za otkrivanje moguće biološke
uloge MUC16/CA125, do sada nije korišćena u ispitivanjima ovog antigena.
Pored toga, u kontekstu diskretnih bioloških funkcija, bez obzira na izuzetan
biomedicinski značaj, ne postoje eksperimentalni podaci o interakcijama
MUC16/CA125 sa specifičnim klasama receptora na ćelijama krvnog sistema. In
silico analiza modularne organizacije MUC16/CA125, vršena je na osnovu
podataka koji su preuze
Adhezija kvasaca i nastanak biofilma na površinama odvijaju se u različitim okruženjima. U prehrambenoj industriji, biofilmovi mogu biti izvor kontaminacije, uzrokujući kvarenje hrane i smanjenje ...kakvoće proizvoda. Kvasci iz rodova Candida i Pichia često su prisutni u hrani i uzrokuju kvarenje nekih prehrambenih proizvoda. Svrha je ovog istraživanja bila procijeniti adheziju kvasaca iz rodova Candida i Pichia na glatke i hrapave drvene površine koje se često koriste u prehrambenoj industriji, te ispitati utjecaj hrapavosti površine drveta na stupanj adhezije. Adhezija stanica kvasaca na drvene površine određena je njihovim ispiranjem s površine, zatim bojenjem metilenskim modrilom i automatskim određivanjem broja živih stanica pod mikroskopom. Rezultati pokazuju da su svi sojevi kvasaca Candida i Pichia imali sposobnost adhezije na drvene površine, ovisno o vrsti i soju. S druge strane, hrapavost drvenih površina nije utjecala na adheziju ispitanih kvasaca.
Upravljanje proklizavanjem bitno je zbog prijenosa adhezijske sile između kotača i tračnica na lokomotivi. Upravljanje proklizavanje sastoji se od dva zadatka. Prvi je određivanje iznosa ...proklizavanja a drugi se sastoji od evaluacija iznosa proklizavanja kroz upravljačke akcije. Navedeni zadaci mogu biti ostvareni koristeći više metoda. Nekoliko metoda se koristi za određivanje adhezijskih koeficijenata ili za određivanje adhezijske sile. Zbog poteškoća prilikom mjerenja adhezijskih koeficijenata ili adhezijske sile tijekom rada vlaka; te veličine je potrebno estimirati. U ovome radu adhezijska sila estimirana je korištenjem kalmanovog filtra koji koristi model lokomotive i mjerenja brzine lokomotive. Filtar je implementiran u Matlabu te je korišten na izmjerenim podacima.
Svrha je rada bila opisati adhezivna svojstva bakterija Lactobacillus fermenti 126 i Lactobacillus rhamnosus CCM 1825 i iz njih izolirati biosurfaktante, te procijeniti njihova funkcionalna svojstva. ...Fourierovom transformiranom infracrvenom spektroskopijom utvrđeno je da se oba biosurfaktanta sastoje od tri komponente: protein, polisaharid i fosfat u različitim omjerima. Neobrađeni biosurfaktanti iz Lactobacillus fermenti 126 i Lactobacillus rhamnosus CCM 1825 imaju 8 i 9 frakcija, koje su analizirane kapilarnom gel-elektroforezom. Biosurfaktant iz Lactobacillus fermenti 126 ima malu učinkovitost, kritičnu micelarnu koncentraciju od 9,0 g/L i površinsku napetost od (45,1±0,1) mN/m. Biosurfaktant iz Lactobacillus rhamnosus CCM 1825 također ima malu učinkovitost, kritičnu micelarnu koncentraciju od 6,0 g/L i površinsku napetost od (43,6±0,6) mN/m. Ima bolja emulgirajuća svojstva i svojstva pjenjenja, stoga bolje inhibira adheziju patogenih bakterija. Oba su soja dobro prianjala na podlogu, a impregnacijom površine od polistirena vodenom otopinom biosurfaktanata spriječena je adhezija patogenih bakterija Escherichia coli 22, Klebsiella pneumoniae 2 i Pseudomonas aeruginosa W2 na podlogu.
Danas se dijelovi i alati sve češće izrađuju iz kombiniranih materijala. Ostvarenje specifične veze između osnovnog materijala i prevlake je izuzetno značajno. Kvaliteta prevlake na proizvodima, sa ...aspekta habanja i otpornosti na razaranje, ima velik utjecaj na produktivnost i pouzdanost proizvodnih procesa, a osobito na njihov vijek trajanja. U radu je na temelju eksperimentalnih istraživanja analiziran utjecaj specifične veze između osnovnog materijala i prevlake na tribološke i zaštitne karakteristike proizvoda.
Razvoj i primjena novih materijala u strojarskoj praksi dovode do mnoštva pitanja u odnosu na njihovu tehnološku primjenu. Ovaj je rad usmjeren na istraživanje problema povezanih s cementiranim ...karbidom premazanim primjenom PVD (Physical Vapour Deposition) metode. U teorijskom dijelu rada upoznaje se PVD tehnologija nanošenja sloja i detaljnije opisuje metoda isparavanja luka. Opisuju se također materijali i vrste slojeva, njihova svojstva, moguće primjene i na kraju objašnjavaju načela eksperimentalnih metoda primijenjenih u ispitivanju slojeva. U eksperimentalnom dijelu rada opisuju se postupci mjerenja i ispitivanja te daju rezultati ispitivanja. Adhezija i trajnost slojeva uspoređeni su na izrezanim umetcima s različitim PVD – premazi s nanostrukturom i nanoslojem. Ispitivanja su provedena glodanjem ugljičnog čelika 1.1191 (C45) budući da se taj čelik uvelike rabi u mnogim industrijskim primjenama, a također i kao referentni material. Na kraju se ocjenjuju rezultati ispitivanja na temelju dobivenih podataka.
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