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Neoadjuvant therapy impact assessment with contrast enhanced ultrasound in patients diagnosed with breast cancer
No full textUvod: CEUS je novija slikovna dijagnostička metoda u radiologiji dojke. Metoda izbora za praćenje učinka neoadjuvantne terapije je MR, kojom je moguće osim morfološke analize procijeniti i imbibiciju te mikrostrukturu lezije. Primjenom ultrazvučnog kontrastnog sredstva također je moguće analizirati prokrvljenost lezije. Neoangiogeneza je odlika malignih lezija, a poznato je da neoadjuvantna terapija primarno djeluje na stanice krvnih žila. Učinci terapije već u ranim fazama liječenja mogu se primijetiti upravo u promjeni imbibicije lezije, dok morfološke promjene slijede naknadno.
Cilj: Utvrditi dijagnostičku točnost CEUS-a kod praćenja djelovanja neoadjuvantne terapije te usporedba s rezultatima MR-a.
Ispitanici i metode: Uključeno je 40 pacijentica te su učinjena 106 pregleda svakom dijagnostičkom metodom, prije početka primjene terapije u sklopu dijagnostičkog protokola te tijekom i/ili po završetku liječenja. Prikupljeni su i analizirani podatci obje metode, a dijagnostička točnost računata je na temelju patohistološkog nalaza i RCB klasifikacije.
Rezultati: Usporedba odgovora na terapiju tijekom i po završetku terapije pokazuje značajnu podudarnost radioloških metoda. CEUS pokazuje veći broj slučajeva podudaranja s patohistološkim nalazom, te nižu osjetljivost uz veću specifičnost i ukupnu dijagnostičku točnost u odnosu na MR. CEUS jednako dobro utvrđuje stupanj bolesti neovisno o podtipu karcinoma dojke.
Zaključak: CEUS dijagnostičkim performansama može parirati MR-u kod praćenja djelovanja neoadjuvantne terapije. Zbog jednostavnosti primjene i izvedbe omogućuje brzi uvid u dinamiku perfuzije karcinoma u stvarnom vremenu.Introduction: Contrast enhanced ultrasound (CEUS) is a relatively new diagnostic method in the breast imaging field. The golden standard for monitoring the effects of the neoadjuvant therapy (NACT) in patients diagnosed with breast cancer is magnetic resonance imaging (MRI), which can be used to assess not only morphological analysis but also imbibition and the microstructure of the lesion. By applying an ultrasound contrast agent it is possible to analyze the blood supply of the lesion. Neoangiogenesis is a feature of malignant lesions and it is well established that neoadjuvant therapy primarily affects the blood vessels that supply it. The effects of and response to the therapy in the early phase of treatment can be noticed precisely in the change in the lesion's imbibition, while morphologic changes usually follow later.
Objective: To determine the diagnostic accuracy of CEUS in monitoring the effect of neoadjuvant therapy and to compare it with MRI results.
Subjects and methods: 40 patients were included and 106 examinations were performed by each diagnostic method before the start of therapy as part of the diagnostic protocol and during and/or after the end of the treatment. The data of both methods was collected and analyzed, and the diagnostic accuracy was calculated based on the pathohistological findings and the RCB classification.
Results: The comparison of the therapy response during and after the completion of the therapy shows a significant congruence of radiological methods. CEUS shows a higher number of cases matching the pathohistological finding, and a lower sensitivity with higher specificity and overall diagnostic accuracy compared to MRI. CEUS determines the stage of the disease equally well regardless of the subtype of breast cancer.
Conclusion: CEUS’s diagnostic performance can match MRI when monitoring the effect of neoadjuvant therapy. Due to the simplicity of the application and performance, it allows a quick insight into the dynamics of cancer perfusions in real time
Identification and quantification of soil hydraulic properties and preferential flow in agricultural hillslope soil
No full textU biljnoj proizvodnji posebno su zahtjevna padinska tla uslijed degradacije tla koja se javlja
kao posljedica obrade i velike heterogenosti u svojstvima tla čak i na relativno malom
području. Navedeno dovodi do pojave neravnotežnih procesa toka i pronosa tvari, odnosno
do bržeg otjecanja agrokemikalija do površinskih voda i/ili podzemnih voda. Glavni cilj
doktorske disertacije bio je utvrditi hidrološke procese koji se odvijaju u tlu tijekom i nakon
pojedinih vremenskih (ne)prilika, a imaju izravan utjecaj na agroekosustav i potencijalne
opasnosti za okoliš putem erozije i onečišćenja površinskih i podzemnih voda.
Istraživanje je provedeno na vinogradarsko-vinarskom pokušalištu Jazbina tijekom
dvogodišnjeg razdoblja (2021. – 2022.) na rigolanom tlu iz pseudogleja obronačnog (Dystric
Stagnosol). Obronak je podijeljen ovisno o nagibu na tri pozicije, odnosno na vrh, sredinu i
dno padine. Nagib između vrha i sredine padine iznosi 17,5 %, dok je između sredine i dna
25,4 %. Na istraživanoj lokaciji su uzeti uzorci tla na vrhu, sredini i dnu u tri ponavljanja
kako bi se odredila fizikalna, kemijska i hidraulička svojstva tla. Na svakoj poziciji su
postavljeni nevagajući tlačni pasivni lizimetri na 40 cm dubine u kojima je mjeren volumen
vode jednom mjesečno. Klimatski podaci prikupljani su na meteorološkoj stanici
postavljenoj na sredini padine. Na dnu padine je mjereno površinsko otjecanje i
potpovršinsko procjeđivanje u tri ponavljanja. Na istraživanoj padini su postavljeni i senzori
za mjerenje volumetrijske vlage tla te vodnog potencijala tla, a na površini tla je mjerena i
infiltracija. Tok vode u tlu je određen aplikacijom briljantno plavog bojila i kalijeva bromida.
Na kraju je provedeno numeričko modeliranje toka i retencije vode u terenskim i
laboratorijskim uvjetima u HYDRUS-1D programu koristeći modele dvostruke poroznosti i
propusnosti.
Provedenim istraživanjima kao najbolji model za procjenu hidrauličkih svojstava tla na
heterogenim tlima pokazao se van Genuchtenov bimodalni model. Analizom prostorne i
vremenske dinamike vodnog režima istraživane padine utvrđen je utjecaj preferencijalnih
tokova na hidrologiju padine. Razlike u toku vode utvrđene su ne samo ovisno o poziciji na
padini nego i između ponavljanja. Također je utvrđena prisutnost lateralnog
preferencijalnog toka kada se nakon pojedinih kišnih događaja nije zabilježila razlika u vlazi
tla na površini, ali je u većim dubinama. Numeričkim modeliranjem utvrđena je najveća
pouzdanost modela dvostruke poroznosti. Model se pokazao pouzdaniji u simulacijama
kolona u usporedbi s terenskim mjerenjima gdje bi se vjerojatno boljim pokazao još
kompleksniji model, na primjer HYDRUS-3D. Utvrđene razlike u toku vode na istraživanoj
padini ovisno o mjesecima, poziciji na padini, ali i mjernim instrumentima upućuju na
opasnost različite brzine transporta agrokemikalija što ima negativni ekološki i financijski utjecaj.Agricultural production on a slope is particularly demanding due to greater degradation
caused by tillage and soil heterogeneity, even on a relatively small area, which can cause
non-equilibrium flow and transport processes i.e., faster runoff of agrochemicals to surface
waters and faster leaching to groundwater. The main aim of this research was to determine
processes happening in the soil after certain weather events and which have a direct impact
on the agroecosystem and potential environmental hazards such as soil erosion and
pollution of surface and groundwater. Thus, the research hypotheses were set as (i)
unimodal functions are not sufficient for the estimation of soil hydraulic properties of
heterogeneous hillslopes with a developed structure; (ii) local heterogeneities have a
dominant influence on the water regime of the investigated hillslope; (iii) the application of
numerical models of dual porosity and permeability allows the quantification of preferential
flows in the soil. The research objectives were set as follows (i) analyse the soil hydraulic
properties in heterogeneous hillslope soils with a developed structure using unimodal and
bimodal functions; (ii) analyse the spatial and temporal dynamics of the soil water regime
of the investigated slope and determine the occurrence of preferential flow in order to
quantify the influence of local soil heterogeneities; (iii) determine the reliability of complex
numerical models for the quantification of non-equilibrium and preferential flow processes.
The study was conducted at Experimental station Jazbina (45⁰51’24’’ N 16⁰00’22’’ E) during
the two years (2021 – 2022). According to the World Reference Base (WRB) classification
system, this location is classified as Dystric Stagnosol. The investigated vineyard is divided
into two parts based on the slope – 17.5% from hillslope to backslope, and 25.4% from
backslope to footslope. Disturbed soil samples were taken in triplicate at the hilltop,
backslope, and footslope from 0 – 30, 30 – 60, and 60 – 90 cm depth to determine the
physicochemical soil properties. Undisturbed soil samples were also taken from the hilltop,
backslope, and footslope from 15 – 20, 35 – 40, 55 – 60, and 70 – 75 cm to estimate the
soil hydraulic properties. Furthermore, wick lysimeters were also set at the hilltop,
backslope, and footslope at 40 cm depth. Lysimeters were used to measure percolated
water once a month. A meteorological station was set at the backslope of the investigated
vineyard and it collects climate data (air temperature, humidity, wind speed and direction,
solar radiation, and precipitation). The volume of the subsurface runoff was measured in
surface runoff instruments set at the footslope in three rows which represents repetitions.
Volume was also measured once a month. At the same position surface runoff instruments
were set to measure the volume of the surface runoff. The dynamics of volume
measurements were the same as for the subsurface runoff. Furthermore, soil moisture and
soil water potential sensors were set at the hilltop and footslope at 40 and 80 cm depth, i.e.
40 cm depth. For precise determination of preferential flow, a thicker sensor network was
set at the same location as the meteorological station. Sensors were set at 15, 30, 50, 75,
and 100 cm with a reading resolution of 15 minutes. Determination of soil infiltration rate
and hydraulic conductivity was obtained using a mini disk infiltrometer. The measurements
were conducted again at the hilltop, backslope, and footslope, while the unsaturated
hydraulic conductivity was calculated via a Microsoft Excel spreadsheet provided by the
manufacturer. Determination of preferential flow was obtained both at the field and in the
controlled conditions using two traces (Brilliant Blue and potassium bromide). After Brilliant
Blue was infiltrated into the soil, the dyed area was analysed in ImageJ, while bromide
concentration was determined in leachate samples collected in wick lysimeters once a
month. Water flow was also determined in controlled conditions on undisturbed soil columns
using Brilliant Blue, potassium bromide, and sensors. Undisturbed soil columns, 25 cm in
depth and 16 cm in diameter, were taken from the field at the hillslope, backslope, and
footslope. All collected data were used for numerical modeling of water flow and water
retention. Simulations on undisturbed soil columns are used to investigate vertical water
flow, while vertical water flow in combination with surface runoff and evapotranspiration was
simulated using data from wick lysimeters. Sensors obtained data for simulations of vertical
and lateral flows, surface runoff, and evapotranspiration. Dual-porosity and dualpermeability
models were used for numerical modeling.
Obtained results showed that for most properties the more complex van Genuchten bimodal
model shows the highest reliability compared to other models. The analysis of the spatial
and temporal dynamics of the water regime of the investigated hillslope showed an
influence of preferential flows on the hydrology of the entire slope. Differences in water flow
were found not only depending on hillslope position but between repetitions as well. The
presence of lateral preferential flow was also seen after certain rainfall events when no
difference in soil moisture was measured on the surface sensor but was measured in
deeper depths. Furthermore, numerical modeling showed the highest reliability of the dual
porosity model. However, it was also proven that the model shows better reliability for
modeling undisturbed soil columns compared to the field conditions. While the conditions
at the field are more complex compared to the soil column, thus the more complex model,
such as HYDRUS-3D would show even greater reliability
CRUSTACEANS IN ECO-EXPOSOMAL EVALUATION OF GROUNDWATER CONNECTED ECOSYSTEMS
No full textCilj ove doktorske disertacije bila je ekoekspozomska analiza fizioloških promjena u rakušca
Synurella ambulans kao posljedica utjecaja okolišnih stresora u ekosustavima povezanim s
podzemnim vodama. Analiza značajki životnog ciklusa ukazala je na prostorno-vremensku
varijabilnost parametara rasta te utjecaj okolišnih čimbenika, posebice temperature,
koncentracije otopljenog kisika i organske tvari u vodi. Vrsta može akumulirati metale iz
okoliša, čak i kada koncentracije metala u intersticijskoj vodi i sedimentima iz hiporeičke zone
nisu odstupale od standarda kvalitete okoliša. Povišene vrijednosti bioakumulacijskih faktora
metala, biomarkera antioksidativne obrane organizma i izloženosti ksenobioticima te niže
vrijednosti energijskog naboja adenilata i niži omjer PK/PEPCK u S. ambulans nizvodno od
ispusta otpadnih voda, u odnosu na uzvodnu lokaciju, ukazuju na negativan antropogeni utjecaj
i povećani anaerobni potencijal. Vrsta S. ambulans je prikladan bioindikator u procjeni stanja
okoliša u hiporeičkoj zoni, važnog za zaštitu ovog ranjivog ekotona esencijalnog za usluge
slatkovodnih ekosustava.The objective of this thesis was an eco-exposome analysis of physiological changes in the amphipod Synurella ambulans as a response to environmental stressors in groundwater connected ecosystems. Life history trait analysis revealed spatio-temporal variation in growth parameters and the influence of environmental parameters, especially water temperature, concentrations of dissolved oxygen and organic matter. The species accumulated metals from the environment even when metal concentrations in interstitial water and sediments did not deviate from environmental quality standards. Increased bioaccumulation factors, biomarkers of antioxidant defense and exposure to xenobiotics, lower levels of adenylate energy charge and a lower PK/PEPCK ratio in S. ambulans downstream of the wastewater outlet compared to the upstream location, indicated a negative anthropogenic influence and increased anaerobic potential. S. ambulans is a suitable bioindicator for environmental assessment in the hyporheic zone, which is important for the protection of this vulnerable ecotone that is essential for freshwater ecosystem services
The role of the inflammatory response and the severity of the disease as a clinical predictor of the development of anxiety, depression and post traumatic stress disorder in patients treated in hospital for COVID 19
No full textNamjera nam je bila istražiti simptome depresije, anksioznosti, stresa i PTSP-a i njihov odnos s težinom bolesti kod akutno bolesnih pacijenata koji su hospitalizirani u KB Dubrava s koronavirusom (COVID-19). Provedena je jednocentrična presječna opservacijska studija u dvjema vremenskim točkama koja je probirala psihijatrijske simptome korištenjem dvije sasmoocjenske psihijatrijske ljestvice. Uključeno je ukupno 169 bolesnika. Svi bolesnici bili su odrasli i bijele rase te su tijekom hospitalizacije razvili respiratornu insuficijenciju. Demografski, klinički i laboratorijski podatci procijenjeni su kao prediktori psihijatrijskih simptoma. Pronašli smo da su intenzitet simptoma bolesti COVID-19 i veća potreba za kisikom bili povezani s pojavom depresije, anksioznosti, stresa i simptoma PTSP-a. Svi psihijatrijski simptomi bili su izraženiji u bolesnica, simptomi depresije i anksioznosti povezani su s prethodnom kroničnom opstruktivnom bolešću pluća. SII i CRP nisu bili statistički značajno povezani s prisutnim simptomima anksioznosti, stresa i depresivnosti, te PTSP-a, naša hipoteza u kojoj smo očekivali povezanost, nije potvrđena. Akutno bolesni hospitalizirani pacijenti pokazali su visoku prevalenciju akutnih psihijatrijskih posljedica, osobito žene, a teži COVID-19 uglavnom je utjecao na težinu simptoma depresije. U postakutnoj fazi nakon 3 mjeseca pokazuje se pad anksioznosti, depresivnosti,stresa isimptoma PTSP-a.We aimed to investigate symptoms of depression, anxiety, stress, and PTSPand their relationship with disease severity in acutely ill patients hospitalized in KB Dubrava with COVID-19. A single-center cross-sectional observational study was conducted at two time points that screened psychiatric symptoms using two self-rated psychiatric scales. A total of 169 patients were included. All patients were adults and of white race and developed respiratory insufficiency during hospitalization. Demographic, clinical and laboratory data were evaluated as predictors of psychiatric symptoms. We found that the intensity of the symptoms of the disease of COVID-19 and a higher need for oxygen were associated with the occurrence of depression, anxiety, stress and PTSD symptoms. All psychiatric symptoms were more pronounced in female patients, symptoms of depression and anxiety were associated with previous chronic obstructive pulmonary disease. SII and CRP were not statistically significantly related to the presence of symptoms of anxiety, stress and depression, and ptsp, our hypothesis in which we expected a connection was not confirmed.Acutely ill hospitalized patients showed a high prevalence of acute psychiatric consequences, especially women, and more severe COVID -19 mainly affected the severity of depressive symptoms.
In the post-acute phase after 3 months, there is a decrease in anxiety, depression and stress and a slight increase in PTSD symptoms (by about 10%)
DEVELOPMENT AND CHARACTERIZATION OF FOOTBALL CLOTHING MATERIALS TO OPTIMIZE COMFORT AND DURABILITY
No full textBavljenje sportom postaje jednim od imperativa suvremenog načina življenja. Takav trend postavlja nove zahtjeve prema funkcionalnosti, udobnosti i estetskoj privlačnosti sportske odjeće. Izbor sportske odjeće ovisi o vrsti aktivnosti i okruženju u kojem se trenira, a svaka sportska disciplina postavlja nove izazove za projektiranje inovativnih materijala. Istraživanje u sklopu doktorskog rada usmjereno je na razvoj i mehaničku funkcionalizaciju pletenih materijala namijenjenih izradi nogometnih sportskih dresova, kako bi isti bili što trajniji i osigurali optimalnu razinu udobnosti tijekom korištenja. U svrhu navedenog, provedeno je anketno istraživanje među nogometnim igračima s ciljem uvida u percepciju igrača vezanu uz udobnost i trajnost nogometnih dresova. Rezultati istraživanja poslužili su za izradu novog protokola starenja materijala za nogometnu odjeću. Za potrebe istraživanja odabrane su konvencionalne, funkcionalne i reciklirane pređe od kojih je dizajniran i izrađen set projektiranih pletiva. Uz projektirana pletiva, na tržištu materijala namijenjenih izradi sportskih nogometnih dresova, nabavljen je i set reprezentativnih pletiva proizvedenih od strane renomiranih proizvođača. Zatim je provedeno ispitivanje svojstava odabranih pređa (finoća, promjer, uvijenost, vlačna svojstva, dlakavost i otpornost na habanje) te projektiranih i reprezentativnih pletiva (strukturni parametri, vlačna svojstva, otpornost na probijanje kuglom, otpornost na habanje, sklonost površinskom stvaranju pilinga, sposobnost prijenosa vlage i propusnost vodene pare). Rezultati provedenog istraživanja dali su smjernice za izradu novog protokola starenja materijala najsličnijeg realnom starenju materijala tijekom korištenja. Pletiva su podvrgnuta različitim ciklusima starenja definiranim prema novo-razvijenom protokolu starenja. Nakon provedenog procesa starenja, provedeno je ispitivanje svojstava pletiva s ciljem detekcije utjecaja starenja na svojstva udobnosti i trajnosti te razvoj smjernica za projektiranje visoko-funkcionalnih materijala.One of the imperatives of the modern way of life became playing sports. Such a trend places new demands on sportswear's functionality, comfort and aesthetic appeal. The choice of sports clothing depends on the type of activity and the environment in which it is trained, and each sports discipline poses new challenges for the design of new innovative materials. The doctoral thesis research focused on the development and mechanical functionalisation of knitted materials, intended for producing football sports jerseys, to provide optimal comfort and durability during use. For the above, a survey was conducted among football players to gain insight into player preferences related to the comfort and durability of football jerseys. The research results were used to create a new material aging protocol. For the research, a set of knitted fabrics was designed and produced, from conventional, functional and recycled yarns. In addition, to the set of designed knitted fabrics, on the market of materials intended for producing sports football jerseys, a set of representative knitted fabrics was also purchased from renowned manufacturers. The properties of selected yarns (count, diameter, number of twists, tensile properties, hairiness and resistance to abrasion), as well as the properties of designed and representative fabrics (structural properties, tensile properties, bursting resistance, abrasion resistance, fabric propensity to surface pilling, moisture management and water vapour permeability), were tested. The guidelines for creating a new aging protocol, the most similar to real material aging, were obtained from the research results. Knitted fabrics were subjected to various aging cycles defined in the newly developed aging protocol. After the aging process, the properties of knitted fabrics were tested to detect the effect of aging on comfort and durability and to establish guidelines for designing highly functional materials
Mikrosfere na temelju kitozana kao sustavi za dostavu lijeka
No full textOsteosarcomas, the most common type of primary bone tumor affecting children, adolescents, and young people, usually occur in long bones and are treated with surgery, which is preceded by biopsy and chemotherapy. Chemotherapy is often continued after surgery. Since antitumor drugs are administered intravenously, very high concentrations are required to inhibit tumor cell growth, exposing the entire body to the effects of the drug. Additionally, conventional chemotherapeutic drugs often have drawbacks, including reduced solubility, nonselective distribution, and adverse effects after oral or intravenous administration, which limit their clinical use. To reduce these negative effects, chitosan (CHT)-based drug delivery systems for local delivery have been proposed. In this study, microspheres based on chitosan physically crosslinked with copper(II) ions (CHT-Cu complex) were successfully prepared by emulsion and electrohydrodynamic atomization (electrospraying) process. Additionally, composite microspheres with calcium phosphate (CaP) ceramics in varying amounts (0, 5, and 10 wt.% of CaPs) were prepared. The emulsion-prepared CHT-Cu/CaP0 microspheres (microspheres without the addition of CaP) were spherical (circularity factor ~1) with a smooth surface and an average size of 30.1 ± 9.1 μm. The size of the electrosprayed microspheres ranged from 50 to 110 μm, depending on the CaP content. FTIR spectroscopy and X-ray diffraction analysis indicated interactions between the CHT-Cu matrix and the precipitated CaP filler, likely in the form of hydroxyapatite. An in vitro Cu2+ release study performed under conditions simulating an in vivo-like physiological environment indicated a significantly higher metal release from the microspheres in a complete cell culture medium compared to phosphate buffer at pH 7.4. Doxorubicin (DOX), used as a model antitumor drug, was incorporated into the CHT-Cu/CaP microspheres utilizing the pH-sensitivity of the CHT matrix. Successful drug loading was confirmed by fluorescence microscopy. DOX release was shown to depend on the pH value and chemical composition of the incubation medium, as well as the chemical composition of the drug-loaded microcarrier, indicating the ability of the DOX-loaded microcarriers to locally release DOX in a pH-triggered manner. It can be assumed that modification of CHT-based microspheres by adding CaPs increased the DOX loading efficiency. Biological evaluation of the as-prepared and drug-loaded microcarriers indicated synergistic effect of the drug and Cu2+ ions, and material selectivity towards MG-63 tumor cells. The optimal DOX-loaded material concentration for inhibiting osteosarcoma cell growth without having a harmful effect on normal cells was 0.5 mg mL^–1. Overall, the physicochemical and biological characterization of the prepared CHT-Cu/CaP microspheres and DOX-loaded microcarriers indicated the successful preparation of smart drug delivery systems for bone tumor treatment.Osteosarkomi, najčešća vrsta primarnog tumora (dugih) kostiju koji se javlja kod djece, adolescenata i mladih ljudi, obično se liječe kirurškim zahvatom, kojem prethode biopsija i kemoterapija. Kemoterapija se često nastavlja i nakon operacije. Budući da se antitumorski lijekovi administriraju intravenozno, potrebne su vrlo visoke koncentracije za inhibiciju rasta tumorskih stanica, a čime se cijelo tijelo izlaže djelovanju lijeka. Nadalje, konvencionalni kemoterapijski lijekovi često imaju štetne učinke, kao što su smanjena topljivost i neselektivna distribucija, što ograničava njihovu kliničku primjenu. Kako bi se smanjili ovi negativni učinci, predloženi su sustavi za lokalnu dostavu lijeka koji se temelje na kitozanu (CHT). U ovom radu, mikrosfere na temelju kitozana fizikalno umreženoga s bakrovim(II) ionima (CHT-Cu kompleks) uspješno su dobivene postupkom iz emulzije i primjenom elektrohidrodinamičke atomizacije (EHDA proces, elektroštrcanje). Dodatno su pripremljene i kompozitne mikrosfere s kalcij-fosfatnom (CaP) keramikom u različitim masenim udjelima (0, 5 i 10 mas.%).
CHT-Cu/CaP0 mikrosfere (mikrosfere bez dodatka CaP) dobivene iz emulzije bile su sferične (faktor sferičnosti ~1) s glatkom površinom i prosječnom veličinom od 30,1 ± 9,1 μm. Prosječna veličina CHT-Cu/CaP mikrosfera dobivenih EHDA procesom bila je između
50 i 110 μm, ovisno o količini CaP punila. FTIR spektroskopija i XRD analiza ukazale su na prisutnost interakcija između CHT-Cu matrice i istaloženoga CaP punila, vjerojatno u obliku hidroksiapatita. Otpuštanje Cu2+ iona iz CHT-Cu/CaP0 mikrosfera istraženo je pri simuliranim fiziološkim uvjetima, te rezultati ukazuju na znatno veće otpuštanje metalnih iona u mediju za staničnu kulturu u odnosu na fosfatni pufer pH vrijednosti 7,4. Doksorubicin (DOX), korišten kao modelni antitumorski lijek, uklopljen je u CHT-Cu/CaP mikrosfere koristeći svojstvo
pH-osjetljivosti CHT matrice. Uspješno uklapanje lijeka u mikronosače potvrđeno je primjenom fluorescentne mikroskopije. Otpuštanje DOX-a iz mikronosača ovisi o pH-vrijednosti i sastavu medija za inkubaciju, te o kemijskom sastavu mikronosača, što ukazuje na to da su
DOX-mikronosači pH-osjetljivi. Također, može se pretpostaviti da je modifikacija CHT-Cu mikrosfera dodatkom CaP-a povećala učinkovitost uklapanja DOX-a. Biološka ispitivanja pripremljenih CHT-Cu/CaP mikrosfera i mikronosača s uklopljenim lijekom pokazala su sinergijski učinak lijeka i Cu2+ iona te selektivnost materijala prema tumorskim stanicama. Kao optimalna koncentracija materijala s DOX-om za inhibiciju rasta stanica osteosarkoma bez štetnog učinka na zdrave stanice pokazala se 0,5 mg mL^–1. Zaključno, fizikalno-kemijska i biološka karakterizacija pripremljenih CHT-Cu/CaP mikrosfera i mikronosača s uklopljenim DOX-om ukazala je na uspješnu pripremu pametnih sustava za isporuku lijekova za liječenje tumora kostiju
The effect of wine and ethanol consumption on the survival and proliferative phase of healing after a surgically-induced myocardial infarction on the rat model
No full textUVOD: Istraživanja o kardioprotektivnim učincima vina uglavnom su usredotočena na crno vino zbog njegovog većeg sadržaja bioaktivnih spojeva u usporedbi s bijelim vinom. Iako neke studije sugeriraju postojanje kardioprotektivnog djelovanja bijelog vina, ne postoji jasan konsenzus o tome nadilaze li te koristi one koje pruža sam etanol. CILJ ISTRAŽIVANJA: Cilj ovog istraživanja bio je analizirati stope preživljenja i imunohistokemijske osobine infiltrata makrofaga te razinu aktivacije miofibroblasta u tkivu miokarda životinja koje su preživjele 96 sati nakon kirurški induciranog infarkta miokarda (IM), a koje su prethodno tijekom četiri tjedna konzumirale bijelo vino, vodenu otopinu etanola ili samu vodu. MATERIJALI I METODE: U studiji je korišteno 80 muških štakora vrste Sprague-Dawley podijeljenih u tri skupine: skupina koja je pila samo vodu, bijelo vino uz vodu ili 13% v/v vodene otopine etanola uz vodu. Nakon četverotjednog perioda konzumacije pića, IM je induciran podvezivanjem prednje interventrikularne arterije. Srca životinja koje su preživjele 96 sati nakon IM-a, te koje su konzumirale najmanje 8 mL alkoholnih pića dnevno i imale usporedive veličine IM-a, prikupljena su za imunohistokemijsku analizu. Uzorci tkiva obojeni su pan-makrofagnim biljegom (CD68) i protuupalnim biljegom makrofaga (CD163) kako bi se procijenila polarizacija makrofaga koja je ključna za cijeljenje nakon IM-a. Osim analize biljega makrofaga, provedeno je i bojanje α-SMA biljegom kako bi se ustanovila i usporedila aktivnost miofibroblasta između eksperimentalnih skupina. REZULTATI: Najviša stopa preživljenja zabilježena je u skupini koja je konzumirala bijelo vino (72,2%), dok je najniža bila u skupini koja je pila samo vodu (47,8%). Nije pronađena statistički značajna razlika u preživljenju između skupina koje su konzumirale vodenu otopinu etanola i vodu. Analiza volumena konzumiranih pića pokazala je da je niža količina konzumirane vodene otopine etanola bila povezana s većim stopama preživljenja. Suprotno tome, kod štakora koji su dnevno konzumirali oko 10 mL ili više bijelog vina nije zabilježen nijedan smrtni ishod. Imunofluorescencijskom analizom obradile su se četiri zone oko infarciranog područja —subepikardijalna, subendokardijalna i dvije periinfarktne zone. U svim analiziranim zonama najveći omjeri broja CD163 i CD68 pozitivnih makrofaga zabilježeni su u skupini koja je konzumirala bijelo vino. Što se tiče izražaja α-SMA, najmanje prosječne vrijednosti biljega dobivene su u vinskoj skupini u svim zonama, no značajnost razlike ustanovljena je samo između vinske i kontrolne skupine u periinfarktnoj zoni. ZAKLJUČAK: Zaključak studije je da umjerena konzumacija bijelog vina poboljšava preživljenje nakon IM-a, vjerojatno zahvaljujući njegovim nealkoholnim sastojcima. Konzumiranje veće količine vodene otopine etanola bilo je povezano s većom smrtnošću životinja, što ukazuje na gornju granicu zaštitnih učinaka ovog alkoholnog pića. Nijedna životinja koja je konzumirala prosječne količine vina ekvivalentne štetnoj količini etanolne otopine nije uginula, što sugerira da vino pruža dodatne zaštitne koristi koje nadmašuju učinke samog etanola. U okviru proliferativne faze cijeljenja, uočena je povećana infiltracija protupalnih naspram proupalnih makrofaga kod životinja koje su konzumirale bijelo vino u usporedbi s onima koje su pile vodenu otopinu etanola i kontrolnim životinjama. Analiza je pokazala i smanjen izražaj α-SMA biljega kod životinja koje su konzumirale bijelo vino, što je posebno naglašeno u periinfarktnoj zoni. Ovi rezultati ukazuju da bijelo vino sadrži sastojke koji dodatno podržavaju proces cijeljenja i smanjuju pretjeranu fibrozu tkiva u odnosu na druge dvije skupine. Sveukupno, istraživanja u podlozi ovog doktorskog rada pokazuju da umjerena konzumacija bijelog vina poboljšava preživljenje te potiče prikladnije cijeljenje nakon IM-a zbog mehanizama koji nadilaze učinke samog etanola, vjerojatno zahvaljujući njegovim nealkoholnim bioaktivnim spojevima.INTRODUCTION: Studies on the cardioprotective effects of wine are primarily focused on red wine due to its higher content of bioactive compounds compared to white wine. Although some studies suggest that white wine may have cardioprotective properties, there is no clear consensus on whether these benefits surpass those provided by ethanol alone. AIM OF THE STUDY: The aim of this study was to analyze the survival rates and immunohistochemical characteristics of macrophage infiltrates and the level of myofibroblast activation in myocardial tissue of animals that survived 96 hours after surgically induced myocardial infarction (MI), and that had previously consumed white wine, aqueous ethanol solution, or water alone for four weeks. MATERIALS AND METHODS: In this study, 80 male Sprague Dawley rats were divided into three groups: one group consumed only water, another consumed white wine along with water, and the third group consumed a 13% v/v ethanol/water solution along with water. After a four-week drinking period, MI was induced by ligating the left anterior descending artery. Hearts from animals that survived the 96-hour post-infarction period, consumed at least 8 mL of alcoholic beverages daily, and had comparable infarct sizes, were collected for immunohistochemical analysis. Tissue samples were stained with CD68, a pan-macrophage marker, and CD163, an anti-inflammatory macrophage marker, to assess macrophage polarization, which is crucial for healing after MI. In addition to macrophage marker analysis, α-SMA staining was performed to establish and compare myofibroblast activity between experimental groups. RESULTS: The highest survival rate was observed in the group that consumed white wine (72.2%), while the lowest was in the group that drank only water (47.8%). No statistically significant difference in survival rate was found between the groups that consumed ethanol solution and water. Analysis of the volumes of consumed beverages indicated that lower amounts of ethanol solution were associated with higher survival rates. Conversely, none of the rats that consumed around 10 mL or more of white wine daily died during the same period. Immunofluorescent analysis focused on four zones around the infarcted area: subepicardial, subendocardial, and two periinfarct zones. The highest ratios of CD163 and CD68 positive macrophages were recorded in the group consuming white wine across all analyzed zones. Regarding the α-SMA expression, the lowest average values were found in the wine group across all zones. However, statistical significance was established only between the wine and control groups in the periinfarct zone. CONCLUSION: The conclusion of the study was that moderate consumption of white wine improves survival after MI, likely due to its non-alcoholic components. Consuming a higher amount of aqueous ethanol solution is associated with higher mortality in animals, suggesting an upper limit to the protective effects of this alcoholic beverage. No animals died consuming higher amounts of white wine suggesting that wine provides additional protective benefits that exceed those of ethanol alone. Within the proliferative phase of healing, an increased infiltration of anti-inflammatory versus pro-inflammatory macrophages was observed in animals that consumed white wine compared to those that drank an aqueous ethanol solution and the control animals. The analysis also showed a reduced expression of the α-SMA marker in animals that consumed white wine, and the effect was especially pronounced in the periinfarct zone. These results indicate that white wine contains ingredients that further support the healing process and reduce excessive tissue fibrosis compared to the other two groups. Overall, the research underlying this doctoral thesis shows that moderate consumption of white wine improves survival and promotes healing after a MI through mechanisms that go beyond the effects of ethanol alone, likely due to its non-alcoholic bioactive compounds
Pulmonary rehabilitation outcome in relation to the nutritional status of patients with chronic obstructive pulmonary disease
No full textUvod: Kronična opstruktivna plućna bolest (KOPB) jedan je od vodećih uzroka smrti u svijetu i predstavlja velik javnozdravstveni problem. Liječenje je kompleksno te uz farmakološke, ključnu ulogu imaju i nefarmakološke mjere, prije svega plućna rehabilitacija. U dosadašnjim brojnim istraživanjima bolesnika s KOPB-om praćene su promjene u nutritivnom statusu bolesnika koje utječu na mortalitet, funkcionalni status bolesnika i kvalitetu života te pozitivan učinak plućne rehabilitacije.
Ispitanici i metode: U istraživanje je bio uključen 121 ispitanik s dijagnozom KOPB-a upućen na plućnu rehabilitaciju u Kliniku za plućne bolesti Jordanovac. Ispitanici su podijeljeni u tri skupine (A, B ili C) ovisno o nutritivnom statusu prema upitniku subjektivne općenite procjene (engl. Subjective Global Assessment - SGA). Svim ispitanicima je učinjena bioimpedancijska analiza i mjerene su vrijednosti albumina i prealbumina u krvi. Mjereni su ishodi plućne rehabilitacije, procjenom funkcijskog kapaciteta vježbanja, težine bolesti i kvalitete života, te su mjerene vrijednosti markera sistemske upale i lipidnog profila ispitanika.
Rezultati: Od svih ispitanika podjednak broj muškaraca i žena je bio u svakoj skupini (A, B i C). Prosječna dob uključenih ispitanika bila je 66,5 ± 7,5 godina uz najstariju populaciju u skupini SGA A. Temeljem bioimpedancijske analize i vrijednosti prealbumina nađene su statistički signifikantne razlike između skupina A, B i C (p<0,001). Usporedbom razlike u poboljšanju vrijednosti plućnih funkcija, 6-minutnog testa hoda te upitnika kvalitete života i težine bolesti između SGA skupine A, B i C, ishodi plućne rehabilitacije su bez statistički signifikantne razlike među skupinama. U laboratorijskim nalazima nije nađena signifikantna razlika u vrijednostima leukocita, CRP-a, fibrinogena i lipidnog profila između SGA skupina A,B i C.
Zaključak: Plućna rehabilitacija poboljšava kapacitet vježbanja i kvalitetu života bolesnika s KOPB-om, neovisno o njihovom nutritivnom statusu.Introduction: Chronic obstructive pulmonary disease (COPD) is one of the leading causes of death in the world and represents a major public health problem. The treatment of those patients is complex and, in addition to pharmacological treatment, non-pharmacological measures are very important, especially pulmonary rehabilitation.
Methods: The study included 121 subjects diagnosed with COPD who were referred for pulmonary rehabilitation at the Clinic for Respiratory disease Jordanovac. Subjects were divided into three groups (A, B and C) depending on nutritional status according to the Subjective Global Assessment (SGA) questionnaire. All subjects underwent bioimpedance analysis and measured albumin and prealbumin blood values. Pulmonary rehabilitation outcomes were measured by assessing the exercise capacity, disease severity and the quality of life. Values of the markers of systemic inflammation and the lipid profile were also measured.
Results: An equal number of men and women were in each group (A, B and C). The average age of the included subjects was 66.5 ± 7.5 years, with the oldest population in the SGA group A. Based on bioimpedance analysis and prealbumin values, statistically significant differences were found between groups A, B and C (p<0.001). By comparing the difference in the improvement of pulmonary function values, the 6-minute walk test and the quality of life questionnaire and disease severity between SGA groups A, B and C, the results of pulmonary rehabilitation were without statistically significant differences between the groups. In the laboratory findings, no significant difference was found in the values of leukocytes, CRP, fibrinogen and lipid profile between SGA groups A, B and C.
Conclusion: Pulmonary rehabilitation improves exercise capacity and quality of life in patients with COPD, regardless of their nutritional status
Procjena karakteristika i oporavka igrača u nogometu zasnovana na podatcima : doktorski rad
No full textData collection in soccer encompasses a variety of methods, ranging from simple daily ques
tionnaires that monitor subjective well-being to more sophisticated approaches such as wearable
sensors that track external load during training and matches. While subjective measures like
wellness questionnaires and Rate of Perceived Exertion (RPE) offer insights into players’ inter
nal states, they fall short of providing comprehensive assessments of players’ physical fitness
and performance. Consequently, the use of wearable sensors has become prevalent, offering
detailed metrics such as distance covered, sprints, accelerations, and energy expenditure. These
metrics enable coaches to better manage training loads, plan sessions and monitor the return-to
play (RTP) process after injuries.
However, traditional methods that aggregate data across entire matches often hide the vari
ations in players’ performance throughout the game. This dissertation addresses this issue by
implementing a minute-by-minute analysis of player physical intensity using wearable data, re
vealing more details about players’ fitness levels. By examining how physical performance
fluctuates within different game contexts, the study provides a more accurate reflection of a
player’s condition and readiness.
The relationship between cognitive load (CL) and physical performance is another critical
aspect explored in this work. WhileCL’simpactontacticalandtechnicalaspects is well-studied,
its effects on physical performance, particularly in real-world settings, remain unexplored. Us
ing data fromtheNASA-TLXquestionnaire, thisresearchinvestigates how varying levels of CL
influence physical metrics such as total distance, high-speed running, and deceleration. More
over, the study applies machine learning (ML) algorithms to classify players into motivation
clusters, offering insights into how different motivational factors might affect performance un
der cognitive stress.
Injury recovery is a crucial area in sports, and the RTP process is crucial in ensuring players
return to competition safely. This dissertation advances the understanding of injury manage
ment by developing ML models to predict recovery duration, using data collected by medical
staff. These models are compared with traditional expert-based predictions, demonstrating that
the integration of expert input with ML techniques enhances the accuracy of recovery time es
timates.
In addition to injury recovery, the research focuses on developing individualized fatigue
and recovery profiles. These profiles are essential for conditioning coaches to tailor training regimens and ensure that players return to their pre-injury fitness levels. By providing a de
tailed, data-driven approach to monitoring physical recovery, this dissertation contributes valu
able tools for optimizing player performance and reducing the risk of re-injury.
This work provides a comprehensive framework for soccer performance and recovery anal
ysis, integrating wearable sensor data, cognitive load assessments, and ML techniques. The
findings offer practical applications for coaches and sports scientists, helping them to better un
derstand and manage the complex dynamics of player fitness and performance throughout the
season.Prikupljanje podataka u nogometu obuhvaća različite metode, od jednostavnih dnevnih upit
nika koji prate subjektivan dojam opterećenja pojedinca, do skupljih tehnoloških pristupa poput
nosivih senzora koji prate vanjsko opterećenje sportaša tijekom treninga i utakmica. Dok sub
jektivne mjere poput upitnika za praćenje dobrobiti i ocjene doživljenog napora (RPE) pružaju
uvid u unutarnje stanje igrača, one nisu dovoljne za sveobuhvatnu sliku karakteristika igrača.
Iz tog razloga je upotreba nosivih senzora postala raširena, pružajući podatke o prijeđenoj udal
jenosti, broju sprintova, ubrzanjima i potrošnji energije. Ove informacije omogućavaju trener
ima bolju kontrolu opterećenja tijekom treninga, planiranje istih i praćenje procesa povratka na
teren nakon ozljeda.
Međutim,tradicionalnemetodeprikupljajupodatkenarazinicijeleutakmicečimeseonemogućava
pregled izvedbe igrača tijekom samog trajanja utakmice. Ova disertacija nastoji riješiti taj prob
lem primjenom podatkovne analize intenziteta igrača minutu-kroz-minutu koristeći podatke no
sivih senzora. Pregledom promjena u fizičkim izvedbama tijekom različnih trenutaka u igri,
pristup pruža precizniji odraz stanja i spremnosti igrača.
Odnos između kognitivnog opterećenja i fizičkog opterećenja igrača također je jedan od
fokusa ovog rada. Dok je utjecaj kognitivnog opterećenja na taktičke i tehničke izvedbe igrača
dobro istražen, njegov utjecaj na njihovo fizičko opterećenje, osobito tijekom utakmica, ostaje
neistražen. Koristeći podatke iz NASA-TLX upitnika, ispituje se kako različite razine kogni
tivnog opterećenja utječu na fizičke mjere poput ukupne prijeđene udaljenosti, sprinta, ubrza
vanja i usporavanja. Nadalje, primjenjuju se algoritmi strojnog učenja za klasifikaciju igrača u
motivacijske grupe, pružajući uvid u to kako različiti motivacijski čimbenici mogu utjecati na
izvedbe pod mentalnim opterećenjem.
Oporavak od ozljeda je jedan od ključnih čimbenika u sportu, a dobro planiranje procesa
oporavka je presudno za siguran povratak igrača na teren. Razvijanjem modela strojnog učenja
koji predviđaju trajanje oporavka nakon mišićnih ozljeda, poboljšava se točnost u samom plani
ranju. Modeli strojnog učenja uspoređeni su s procjenama stručnjaka, gdje se pokazalo kako je
upravo kombinacija modela i znanja stručnjaka najbolja za procjenu vremena oporavka.
Kondicijski treneri moraju dobro poznavati igrače kako bi iz svakog izvukli maksimum i
pripremili ih za sezonu. Iz tog razloga, vrlo je korisno imati uvid u individualni profil fizičke
spreme igrača kako bi treneri mogli prilagoditi program treninga. Podatkovni pristup doprinosi
lakšem praćenju opterećenja i smanjivanju rizika igrača od ozljede. Korištenjem podataka iz različitih izvora, kreirane su metode koje treneri, analitičari, i sve
osobekojeradeunogometumogukoristitikakobidobilidetaljnijeinformacijeosvojimigračima.
Podatci su dobiveni korištenjem nosivih senzora i upitnika za procjenu kognitivnog opterećenja
te su isti iskorišteni na različiti načine uz primjenu tehnika strojnog učenja i optimizacije. Cilj
ovakvog pristupa je razvijanje objektivnih metoda koje se mogu automatizirati i olakšati posao
ljudima koji rade u nogometu
Ekotoksičnost mikroplastike i prioritetnih onečišćivala u vodi
No full textPlastics is an inevitable part of our daily life, hence its usage will continue to grow. Multiple and prolonged use and abrasion of the plastic surface might result in partial deterioration of plastic to micro-sized particles – microplastic (MP). Recently, it has been observed that MP’s multi-faceted structural and surface properties makes it an adsorbent for numerous aquatic pollutants such as pharmaceuticals and pesticides, defined under the EU water protection legislation as contaminants of emerging concern (CECs). Their hydrophobicity, polarity and low-biodegradability makes them readily adsorbable at polar, hydrophobic, aged and degraded specific surfaces of MP, contributing to the overall toxicity of such binary systems. Besides, in environmental conditions MP might leach additives and constituents that are often found toxic and hazard. The aim of this dissertation was to investigate the influence of thermal- and photo-aging of polyethylene terephthalate (PET) and polypropylene (PP) on the changes in morphology and structure of polymer materials and the overall ecotoxicity of PET and PP MPs in water. The characterization of pristine and aged MPs was performed by Fourier-transform infrared spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), as well as Water Contact Angle (goniometer) and the Branuer Emmett Teller (BET) specific surface area measurements. In order to investigate the fragmentation of plastic materials into MPs, grinding was performed in a single-drum cryogenic mill, while size distribution of obtained MPs particles was determined by the sieve shaker with five sieves of different mesh sizes to separate the particles according to their size. Adsorption of selected CECs, pharmaceutical diclofenac (DCF) and pesticide atrazine (ATZ), was investigated on both pristine and aged MPs according to the computational/empirical approach employing Full Factorial Design (FFD) as the experimental plan in the combination with Response Surface Modelling (RSM). Furthermore, pristine and aged MPs along with PP waste packaging films, were submitted to leaching tests in order to study possible migration of consituents. The main focus of this dissertation was the evaluation of the aquatic ecotoxicity of the samples after the adsorption and leaching tests and it was tested on the marine bacteria Vibrio fischeri (VF), freshwater crustacean Daphnia magna (DM) and green microalgae Raphidocelis subcapitata (RS), following the procedures disclosed in ISO 11348-3:2007, ISO 6341:2012 and ISO 8692:2012 standards, respectively. Finally, the leachates were tested for their biodegradability, along with glucose as readiliy biodegradable substrate. Based on the obtained results, it is possible to establish a direct relationship between the aging of MP and the increase in its toxicity. Characterization revealed severe degradation of material; thermal-aging affected the structure, while photo-aging caused the surface alterations of PET and PP. Hence, changes in surface morphology such as cracks, fractures, notches and bumps were observed.
The increase in crystallinity of PET and PP resulted in changes of brittleness and accelerated fragmentation to smaller MP’s particles. It was found that hydrophobicity increased, while specific surface decreased; the exception was photo-aged PP. Adsorption of CECs onto MPs is correlated with the changes in the surface morphology enhanced with the photo-aging. Adsorption of CECs was driven by hydrophobicity and specific surface, as well as smaller MP particle sizes as a result of accelerated and prolonged aging period.
RSM approach revealed that temperature is a more significant parameter than MP dosage for CECs adsorption. It can be concluded that aquatic ecotoxicity generally increases with the prolonged exposure to aging, especially valid for the photo-aged MPs. However, some exceptions were observed depending on the type of MPs, CECs and targeted toxicity test organism. Individual CECs showed high ecotoxicity effects toward DM, while slightly lower effects were recorded toward RS. It was also found that DM was the most sensitive organism to the exposure to MPs, with and without CECs. The aging of MPs resulted with the accelerated leaching of constituents for both PET and PP, resulting with ecotoxic responses in cases of all three tested organisms. However, DM was shown to be the most sensitive to leachates originated from PP-MP, while in the case of PET leachates other two test organisms (VF and RS) were more sensitive in ecotoxicity response than DM.
The biodegradability of glucose was inhibited by the presence of (heavy) metals in leachates originated from both thermal- and photo-aged PET and PP MPs.Plastika je neizbježan dio svakodnevnog života i smatra se kako će njezina uporaba nastaviti rasti. Višestruka i dugotrajna uporaba te abrazija površine plastike može rezultirati djelomičnom fragmentacijom na čestice mikro veličine – mikroplastiku (MP). Nedavno je uočeno kako mikroplastika ima brojna strukturna i površinska svojstva koja je čine adsorbentom za brojna onečišćivala pristutna u vodi kao što su farmaceutici i pesticidi, koji su prema vodnom zakonodavstvu EU-a definirani kao onečišćivala koja izazivaju zabrinutost (eng. Contaminants of Emerging Concern, CEC). Njihova hidrofobnost, polarnost i slaba biorazgradivost čine ih toksičnima, a lako se apsorbiraju na polarnu, hidrofobnu, ostarenu i degradiranu specifičnu površinu MP. U okolišnim uvjetima može doći i do izluživanja (eng. leaching) aditiva te konstituenata koji mogu biti ekotoksični i opasni za organizme.
Cilj ove disertacije bio je istražiti utjecaj termo- i foto- starenja poli(etilen- tereftalata) (PET) i polipropilena (PP) na promjenu morfologije i strukture materijala te ekotoksičnost mikroplastike u vodi. Karakterizacija nestarene i starene MP provedena je pomoću infracrvene spektroskopije s Fourierovom transformacijom (FTIR), diferencijalne pretražne kalorimetrije (DSC), termogravimetrijske analize (TGA), skenirajuće elektronske mikroskopije (SEM), kao i goniometra za određivanje kontaktnog kuta vode te mjerenjem specifične površine na temelju Branuer Emmett Teller (BET) modela. Kako bi se istražila fragmentacija plastike u MP, usitnjavanje je provedeno u kugličnom kriogenom mlinu, dok je raspodjela veličine dobivenih MP čestica određena pomoću vibracijske tresilice s pet sita različitih veličina otvora za izdvajanje čestica prema njihovoj veličini. Adsorpcija CEC-a, farmaceutika diklofenaka (DCF) i pesticida atrazina (ATZ) ispitana je i na nestarenoj i starenoj MP u skladu s računalnim/empirijskim pristupom na temelju punog faktorskog dizajna (eng. Full Factorial Design, FFD) u kombinaciji s metodologijom odzivne površine (eng. Response Surface Methdology, RSM). Nadalje, nestarena i starena MP zajedno s otpadnim ambalažnim PP filmovima, podvrgnuti su testovima izluživanja kako bi se ispitala moguća migracija konstituenata. Glavni fokus ove disertacije bila je procjena ekotoksičnosti uzoraka u vodi nakon provedenog procesa adsorpcije i izluživanja i to na morskim bakterijama Vibrio fischeri (VF), slatkovodnim račićima Daphnia magna (DM) i zelenim mikroalgama Raphidocelis subcapitata (RS), prema standardima ISO 11348-3: 2007, norme ISO 6341:2012 i ISO 8692:2012. Na kraju, ispitana je i biorazgradivost uzoraka nakon testa izluživanja, zajedno s glukozom kao lako biorazgradivim supstratom. Na temelju dobivenih rezultata, moguće je utvrditi izravnu vezu između starenja MP- i povećanja njezine toksičnosti. Karakterizacija je pokazala da su procesi termooksidacije i fotooksidacije uzrokovali degradaciju materijala, gdje je termooksidacija utjecala na strukturu, dok je fotooksidacija uglavnom utjecala na površinske promjene PET- i PP-. Stoga su uočene promjene u morfologiji površine kao što su pukotine, lomovi, zarezi i neravnine. Povećanje kristalnosti PET-a i PP-a rezultiralo je promjenom lomljivosti i ubrzanom fragmentacijom na manje čestice MP-a. Uočeno je je povećanje hidrofobnosti i smanjenje specifične površine, osim u slučaju starenog PP-a. Adsorpcija CEC-ova na površinu MP-a u korelaciji je s promjenama morfologije površine nastalim fotooksidativnim starenjem. Hidrofobnost i specifična površina, zajedno s manjim veličinama čestica starenog MP-a, potaknuli su adsorpciju hidrofobnih CEC-ova. RSM ukazuje na to kako je temperatura značajniji parametar od udjela MP za adsorpciju CEC-ova. Može se zaključiti da vodena ekotoksičnost općenito raste s produljenom izloženošću starenju, posebno za foto-stareni MP. Međutim, primijećene su neke iznimke ovisno o vrsti MP-a, CEC-a i ciljanog organizma za ispitivanje ekotoksičnosti. Pojedinačni CEC-ovi pokazali su visoke ekotoksične učinke prema DM, dok su nešto niži učinci zabilježeni prema RS. Također je utvrđeno da je DM najosjetljiviji organizam na izloženost MP, sa i bez CEC-ova. Posebno je DM pokazala visoku osjetljivost na MP, sa i bez adsorbiranih CEC-ova.
Starenje MP rezultiralo je pojačanim izluživanjem konstituenata iz PET-a i PP-a, što je rezultiralo ekotoksičnim odgovorima u slučajevima sva tri testirana organizma. Međutim, pokazalo se kako je DM najosjetljiviji na izluživanje PP-MP, dok su u slučaju izluživanja
PET-MP osjetljivija druga dva testna organizma (VF i RS). Biorazgradivost glukoze bila je inhibirana prisutnošću (teških) metala u uzorcima nakon izluživanja koje potječu iz termo- i foto-starenih PET-MP i PP-MP