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Expression of Hedgehog GLI signaling pathway members in primary human head and neck tumor cell lines
No full textSignalni put Hedgehog-GLI (HH-GLI) je ključan u embrionalnom razvoju čovjeka i drugih sisavaca, a u odraslom organizmu aktivan je samo u održavanju matičnih stanica i cijeljenju rana. Transkripcijski faktori GLI mogu doprinijeti nenormalnoj funkciji ili regulaciji signalizacije što često dovodi do razvoja karcinoma kao što je karcinom pločastih stanica glave i vrata (HNSCC). On obuhvaća tumore koji nastaju u usnoj šupljini, grkljanu, gornjem, srednjem i donjem dijelu ždrijela i žlijezdama slinovnicama te po zastupljenosti predstavlja 6% svih karcinoma u ljudskoj populaciji s izuzetno visokim postotkom smrtnosti. Ovo istraživanje imalo je za cilj proučavanje tumorskih stanica stvaranjem primarnih staničnih linija. Uspoređivali smo gene signalnog puta HH-GLI u tim staničnim linijama s onima u tumorima iz kojih potječu. Također, testirali smo određene inhibitore signalnog puta HH-GLI kako bi se uvidio njihov utjecaj na ekspresiju gena i proteina. Osim toga, usporedili smo dobivene rezultate s onima dobivenim drugim istraživanjem na komercijalnim staničnim linijama. Utvrđeno je da inhibitori, poput LiCl, GANT61 i ATO, različito utječu na signalni put HH-GLI. Konkretno, primijećeno je da LiCl aktivira fosforilaciju GSK3β u citoplazmi, dok GANT61 i ATO, kada se nalaze u jezgri stanice, djeluju izravno na faktore transkripcije. Razumijevanje i manipuliranje tim molekularnim mehanizmima moglo bi utrti put inovativnim terapijskim pristupima u borbi protiv raka povezanih s deregulacijom HH-GLI.The Hedgehog GLI (HH GLI) signaling pathway plays a crucial role in the embryonic
development of humans and other mammals. In the adult organism, its activation is limited to
the stem cells maintenance and wound healing processes. However, dysregulation of GLI
transcription factors in this pathway can lead to aberrant signaling, often contributing to the
development of cancers, such as head and neck squamous cell carcinoma (HNSCC). HNSCC
encompasses tumors arising in various regions, including the oral cavity, larynx, pharynx
(upper, mi ddle, and lower parts), and s alivary glands. It constitutes approximately 6% of all
cancers and is associated with a particularly high mortality rate. This research aimed to study
tumor cells by creating primary cell lines. We compared the HH GLI pathway genes in these
cell lines with those in the tumors they originated from . We also tested certain inhibitors on a
HH GLI pathway to see how they affected expression of genes and proteins. We also compared
our results with another study on commercial cell line s. The inhibitors, like LiCl, GANT61, and
ATO, were found to impact the HH GLI pathway differently. Specifically, LiCl was observed
to activate GSK3 β phosphorylation in the cytoplasm, while GANT61 and ATO, when located
in the cell nucleus , act directly towards influencing transcription factors . Understanding and
manipulating these molecular mechanisms could pave the way for innovative therapeutic
approaches in fighting cancers associated with HH GLI dysregulation
Effect of iron nanoparticles functionalization on Er(III) ion sorption from aqueous solutions
No full textErbijevi spojevi najviše se koriste u izradi optičkih vodiča, lasera i u nuklearnim industrijama te stoga dospijevaju u okoliš. Zbog ograničenih resursa, učinkovito odvajanje erbija predmet je brojnih istraživanja. U ovom radu provedeni su u vodenom mediju eksperimenti sorpcije iona Er3+ pri različitim početnim koncentracijama na neutralnim nanočesticama željeza (nZVI) i nanočesticama željeza modificiranim s dipikolinskom kiselinom (nZVI/PDCA). Nefunkcionalizirane neutralne nanočestice željeza nZVI pokazale su iznimnu efikasnost sorpcije iona erbija (97-99 %) dok su modificirane čestice nZVI/PDCA pri istim dodanim koncentracijama iona erbija u vodenoj otopini za 16 % manje efikasne. Morfološke značajke nefunkcionaliziranih i modificiranih nanočestica prije i nakon sorpcije iona Er3+ dobivene metodom SEM ukazuju na sferične lančaste strukture nemodificiranih nanočestica te sitnije eliptične nakupine modificiranih nanočestica. Utvrđene razlike u morfologiji kod obje vrste čestica pridonose razumijevanju mogućih mehanizama sorpcije.Erbium compounds are mostly used in the production of optical guides, lasers and in the nuclear industry, and therefore end up in the environment. Due to limited resources, the efficient separation of erbium is the subject of numerous investigations. In this work, Er3+ ion sorption experiments in an aqueous medium at different initial concentrations on neutral iron nanoparticles (nZVI) and particles modified with dipicoline acid (nZVI/PDCA) were carried out. Non-functionalized nZVI nanoparticles showed exceptional erbium ion sorption efficiency (97-99 %), while modified nZVI/PDCA nanoparticles at the same added concentrations of erbium ions in water are 16% less efficient compared to non-functionalized nZVI particles. Morphological features of neutral iron nanoparticles and nanoparticles modified with dipicoline acid before and after Er3+ ion sorption obtained by the SEM method indicate spherical chain structures of bare particles and smaller elliptical clusters of modified particles. The determined differences in the morphology of both types of nanoparticles contribute to the understanding of possible sorption mechanisms
Strukturna i funkcionalna karakterizacija proteinskog kompleksa hijauronidaze
No full textThe extracellular matrix (ECM) is a complex network of macromolecules that play essential structural and functional roles in tissue organization and the regulation of cellular processes. It undergoes continuous remodeling, primarily mediated by matrix metalloproteinases (MMPs), serine proteases (e.g., human neutrophil elastase, HNE), and hyaluronidases (Hyal). However, these enzymes also contribute to pathological tissue remodeling, leading to conditions such as inflammation, tumor progression, and metastasis. Understanding their molecular characteristics and detailed mechanisms, and developing potential inhibitors is a significant challenge. Despite growing interest, there are only a few studies detailing their protein structures, spatial conformations, oligomerization, physicochemical properties (e.g., the exact pI value for Hyal), or the relationship between their catalytic activity and preparation/analysis conditions. Additionally, the literature lacks information regarding the quality or purity of samples used in catalytic and affinity assays, and the impact of sample quality on in vitro results. This internship project utilizes highly complementary analytical tools. Quality control by UHPLC-ESI-QTOF MS with online desalting and MALDI-TOF MS confirmed the good quality of HNE, MMP-1, and Hyal2 preparations but revealed that BTH is surprisingly impure. Proteomics assays even detected the presence of BSA in BTH samples. Native Liquid MALDI successfully characterized the oligomerization of HNE, MMP-1, and Hyal2. Results indicated that HNE does not form oligomers, MMP-1 forms dimers, and Hyal2 forms tetramers. Furthermore, a significant influence of a crowding agent (dextran 476 kDa) used to mimic the ECM on the inhibition of BTH by both natural and synthetic compounds was demonstrated by CE-UV catalytic assays and by MST affinity tests. This finding underscores the importance of studying proteins under conditions that closely resemble physiological environments. The innovative information collected during this internship will significantly advance studies on ECM targets
Screening of N-acetylneuraminic acid synthase analogues on unnatural substrates
No full textSijalinske kiseline mogu posredovati ili modulirati u širokom spektru fizioloških i patoloških procesa zbog svoje sveprisutne distribucije i strateške lokacije. U posljednjem desetljeću postignut je značajan napredak u proučavanju glikana na ljudskim stanicama, kao i njihove uloge u interakcijama među stanicama. Ugljikohidrati igraju mnogobrojne uloge u različitim organizmima, uključujući razvoj, signalizaciju, interakcije između domaćina i parazita te imunološku funkciju. Iako je provedeno mnogo istraživanja, biologija sijalinske kiseline je još uvijek rastuće područje velikog potencijala čije su primjene tek započele. U ovom radu provedena je kondenzacijska reakcija šećera (L-arabinoza, D-galaktoza, D-liksoza,
D-(+)-manoza) i fosfoenolpiruvata uz prisutnost metalnog kofaktora Co2+. Reakcije su katalizirane analozima sintaze N-acetinneuraminske kiseline (PNH2, PNH5), umjetno dobiveni na temelju sličnosti sa sintazom neuraminske kiseline iz bakterije Neisseria meningitidis. Produkt reakcija su različite sijalinske kiseline. Provedena su ispitivanja s ekstraktom stanica te s pročišćenim enzimom radi potvrde aktivnosti enzima i nastajanja analognih produkata sijalinske kiseline. Uočena je najveća kompatibilnost enzima PNH5 s testiranim šećerima.Sialic acids can mediate or modulate a wide range of physiological and pathological processes due to their omnipresent distribution and strategic location. In the past decade, significant progress has been made in the study of glycans on human cells, as well as their role in cell-cell interactions. Carbohydrates play numerous roles in various organisms, including development, signaling, host-parasite interactions, and immune function. Although much research has been conducted, sialic acid biology is still an emerging field with great potential, while its applications are just beginning. In this study, a condensation reaction of sugars (L-arabinose, D-galactose, D-lyxose, D-(+)-mannose) and phosphoenolpyruvate in the presence of the metal cofactor Co2+. The reactions were catalyzed by analogs of
N-acetylneuraminic acid synthase (PNH2, PNH5), which were artificially derived based on their similarity to the neuraminic acid synthase from the bacterium Neisseria meningitidis.
The product of the reactions are different sialic acids. Assays were conducted on both
cell-free extracts and purified enzyme to confirm the enzyme activity and the formation of sialic acid analogs. The highest compatibility of the enzyme PNH5 with the tested sugars was observed
Landscape design of Copacabana beach in Osijek
No full textPlaža Copacabana u Osijeku, smještena na sjevernoj obali rijeke Drave, vrijedan je javni otvoreni prostor rekreacijskog karaktera s izraženim društvenim, krajobraznim i ekološkim potencijalima, ali i brojnim funkcionalnim ograničenjima. U radu su analizirani ključni prostorni problemi koji umanjuju njegovu uporabnu i oblikovnu vrijednost. Na temelju prostorne inventarizacije, analize i višekriterijske analize izrađeno je idejno krajobrazno rješenje koje uključuje unaprjeđenje prostorne strukture i uvođenje novih sadržaja te unaprjeđenja prostorne funkcionalnosti i ambijentalne vrijednosti. Prijedlog se temelji na načelima održivog oblikovanja i multifunkcionalnosti, s ciljem afirmacije identiteta prostora i njegove integracije u širi sustav zelene infrastrukture grada.The Copacabana Beach in Osijek, located on the northern bank of the Drava River, is a valuable public open space with a recreational character and pronounced social, landscape, and ecological potential, but also numerous functional limitations. This paper analyzes the key spatial issues that reduce its usability and design value. Based on spatial inventory, analysis, and multi-criteria evaluation, a conceptual landscape design proposal has been developed. It includes the improvement of spatial structure, the introduction of new amenities, and the enhancement of spatial functionality and ambient value. The proposal is grounded in the principles of sustainable design and multifunctionality, with the aim of affirming the identity of the space and integrating it into the broader green infrastructure system of the city
Revitalization of open spaces surrounding the “Rakete” residential towers in Zagreb
No full textOvaj završni rad iznosi idejno krajobrazno rješenje revitalizacije otvorenih površina oko stambenog kompleksa „Rakete“ na zagrebačkom Vrbiku. Prostor, unatoč arhitektonskoj prepoznatljivosti, suočen je s infrastrukturnim i funkcionalnim nedostacima otvorenih površina te slabom prepoznatljivošću i povezanošću s urbanim kontekstom. U sklopu rada provedene su višekriterijske analize otvorenih površina te su na temelju tih rezultata odabrane i predložene mjere krajobrazne revitalizacije, očuvanja ambijentalnog identiteta te tehničke modernizacije. Predloženo idejno rješenje usmjereno je na stvaranje funkcionalnog, inkluzivnog i održivog javnog otvorenog prostora, uz smjernice za daljnju provedbu.This final thesis presents a conceptual landscape design for the revitalization of the open spaces surrounding the “Rakete” residential complex in the Vrbik neighborhood of Zagreb. Despite its architectural recognizability, the area faces infrastructural and functional deficiencies in its open spaces, as well as weak visibility and integration within the urban context. Within the scope of the thesis, multi-criteria analyses of the open spaces were conducted, based on which measures for landscape revitalization, preservation of ambient identity, and technical modernization were selected and proposed. The proposed conceptual design is aimed at creating a functional, inclusive, and sustainable public open space, accompanied by guidelines for further implementation
Impact of storage conditions on the aromatic profile of virgin olive oils : bachelor thesis
No full textMaslina (Olea europea) jedna je od najstarijih kultiviranih biljaka i ključna kultura u jadranskom dijelu Hrvatske. Djevičanska maslinova ulja, proizvedena isključivo mehaničkim postupcima tiještenja zdravih plodova masline, izdvajaju se svojim jedinstvenim sastavom i aromom. Hlapljivi spojevi koji se razvijaju tijekom i nakon ekstrakcije ulja značajno doprinose njegovom aromatičnom profilu. Osim berbe i prerade, na kvalitetu maslinovog ulja utječu adekvatna dorada i pravilno skladištenje, što je ključno za očuvanje ulja i zaštitu od štetnih vanjskih utjecaja. Cilj ovog Završnog rada bio je ispitati utjecaj načina čuvanja djevičanskog maslinovog ulja, dobivenog preradom različitih sorti maslina (Oblica, Leccino i Levantinka) ubranih s dva različita lokaliteta, na aromatični profil ulja. Uzroci su čuvani na tri načina: u tamnoj staklenoj boci na suhom i tamnom mjestu, u inox spremniku te u inox spremniku s dušikom u natprostoru. Analize su provedene svako 6 mjeseci u periodu od 18 mjeseci. Iz dobivenih rezultata utvrđeno je da odabir načina čuvanja ima izražen utjecaj na aromatični profil djevičanskih maslinovih ulja. Rezultati svih načina čuvanja ulja pokazali su blagi trend pada hlapljivih spojeva koji se povezuju pozitivnim aromama. Čuvanje ulja u tamnoj staklenoj boci i inox spremnicima s dušikom u natprostoru se pokazalo kao izrazito dobar način čuvanja, naročito za sprječavanja procesa oksidacije. Ulja čuvana u inox spremniku bez korištenja dušika u natprostoru bila su podložnija procesima oksidacije što je rezultiralo povećanim udjelom hlapljivih spojeva koji se povezuju s negativnim aromama ulja.The olive (lat. Olea europea) is one of the oldest cultivated plants and a key crop in the Adriatic region of Croatia. Virgin olive oils, produced exclusively through mechanical processes by pressing healthy olive fruits, stand out due to their unique composition and aroma. The volatile compounds that develop during and after the oil extraction significantly contribute to its aromatic profile. In addition to harvesting and processing, the quality of olive oil is influenced by appropriate refinement and proper storage, which are crucial for preserving the oil and protecting it from harmful external factors. The aim of this thesis was to investigate the impact of storage methods on the aromatic profile of virgin olive oil obtained from the processing of different olive varieties (Oblica, Leccino, and Levantinka) harvested from two different locations. The samples were stored in three different ways: in a dark glass bottle in a dry and dark place, in a stainless steel tank, and in a stainless steel tank with nitrogen in the headspace. Analyses were conducted every six months over a period of 18 months. The results indicated that the choice of storage condition has a significant effect on the aromatic profile of the virgin olive oil. The results of all methods of oil storage showed a slight trend of decreasing volatile compounds associated with positive aromas. Storing the oil in a dark glass bottle and in nitrogen-filled stainless steel tanks proved to be an extremely effective way to preserve the oil, particularly in preventing oxidation processes. In contrast, oils stored in a stainless steel tank without using nitrogen in the headspace were more susceptible to oxidation processes, which resulted in an increased proportion of volatile compounds that are associated with the negative aromas of the oil
SEASONAL DYNAMICS AND DISTRIBUTION OF INVASIVE ALIEN MOSQUITO SPECIES IN BROD-POSAVINA COUNTY
No full textAzijski tigrasti komarac Aedes (Stegomyia) albopictus (Skuse, 1895) i japanski komarac Aedes japonicus (Theobald, 1901) (Diptera; Culidae) su vrste koje izvorno potječu s tropskih i suptropskih područja jugoistočne Azije, no u zadnjih su se nekoliko desetljeća putem trgovine starih guma motornih vozila i uvozom ukrasne biljke Dracena sanderiana (Masters) (engl. lucky bamboo) rasprostranile diljem svijeta. U Hrvatskoj je vrsta Ae. albopictus prvi put zabilježena 2004. godine, a u Brodsko-posavskoj županiji 2016. godine. Prva pojava vrste Ae. japonicus u Hrvatskoj je dokumentirana 2013. godine, a u Brodsko-posavskoj županiji 2017. godine. Monitoring je proveden u razdoblju od svibnja do listopada 2019. godine u suradnji sa Zavodom za javno zdravstvo Brodsko-posavske županije, a u sklopu nacionalnog sustava praćenja invazivnih vrsta komaraca na području Republike Hrvatske. Rezultati su potvrdili prisutnost obiju vrsta uz izraženu dominantnost vrste Ae. albopictus. Azijski tigrasti komarac je zbog svoje uloge u prijenosu uzročnika bolesti, prvenstveno, dengue, chikungunya i žute groznice, od velikog javnozdravstvenog značaja te zahtijeva kontrolu na globalnoj razini. U svrhu očuvanja zdravlja ljudi nužna je edukacija šire javnosti koja bi zajedno s primjenom ciljanih tretmana suzbijanja komaraca pridonijela sprječavanju distribucije i smanjenju brojnosti invazivnih vrsta komaraca.The Asian tiger mosquito Aedes (Stegomyia) albopictus (Skuse, 1895) and Asian bush
mosquito Aedes japonicus (Theobald, 1901) (Diptera; Culidae) both originate from the tropical and subtropical areas of Southeast Asia, but in the last few decades have spread globally with the help of the international trade of used tires and decorative plant Dracena sanderiana (Masters) better known as „lucky bamboo“. First specimen of Ae. albopictus mosquito in Croatia was collected in 2004, and in Brod-Posavina County in 2016. First findings of Ae. japonicus in Croatia were recorded in 2013, and in Brod-Posavina County in 2017. The monitoring was conducted between May and October of 2019 in cooperation with Institute for Public Health of Brod-Posavina County as a part of the national system for monitoring of invasive mosquito species in Croatia. The results showed the presence of both species and also dominance of Ae. albopictus compared to Ae. japonicus. The Asian tiger mosquito is of major public health concern as it is a vector of pathogens,
primarily yellow fever, dengue and chikungunya viruses, therefore it has to be monitored on a global scale. In order to preserve public health both the public education and focused mosquito control strategies are need to prevent the invasion, establishment, and colonization of invasive mosquito species
Valorization of the newly founded European snake-eyed skink population (Ablepharus kitaibelii) on Stinice
No full textIvanjski rovaš (Ablepharus kitaibelii) je najmanji gušter u Hrvatskoj te jedan od najmanjih
guštera Europe. Njegova ukupna dužina tijela doseže najviše 13 cm dok im je težina između
0,7 i 1,5 grama. U Hrvatskoj je ivanjski rovaš ograničen na vrlo malo područje u Parku prirode
Papuk te na nekoliko lokaliteta u gradu Iloku i bližoj okolici. Na Papuku je vrsta ograničena na
područje toplih južnih padina vrhova Turjak-Mališćak-Pliš, iznad Velike. U 2019. godini vrsta
je zabilježena na novom lokalitetu, na Stinicama. Cilj ovog rada je dokazati prisutnost ivanjskog
rovaša na Stinicama te utvrditi opstojnost i relativnu gustoću ove populacije. Jednostavnom
metodom lova rukom, vaganjem i mjerenjem prikupljene su morfometrijske mjere, a
pretraživanjem linearnih transekata prikupljeni su podaci pomoću kojih je određena relativna
gustoća populacije. Podaci su uspoređeni s prethodnim istraživanjima ivanjskog rovaša na
Turjaku, do sada najistraženijem nalazištu ivanjskog rovaša na Papuku. Populacija na Stinicama
je manje gustoće od populacije na Turjaku te jedinke imaju veće dimenzije glave i udaljenost
između vrha njuške i prednjih udova.European snake-eyed skink (Ablepharus kitaibelii) is the smallest lizard in Croatia, and one of
the smallest lizards in Europe. Its total body length reaches a maximum of 13 cm while their
weight is between 0.7 and 1.5 grams. In Croatia, snake-eyed skink is limited to a very small
area in the Papuk Nature Park, and several localities in the town of Ilok and the surrounding
area. On Papuk, the species is limited to an area of the warm southern slopes of the TurjakMališćak-Pliš peaks, above Velika. In the year 2019, the species was documented on a new
location, on Stinice. The aim of this study is to confirm the presence of European snake-eyed
skink on Stinice, and to determine sustainability and relative density of this population. All
individuals were caught by hand, and their weight and morphometric measures were taken.
Relative population density was estimated based on linear transects data. Obtained data was
compared with the previous research of European snake-eyed skink on Turjak, the most
researched site of European snake-eyed skink on Papuk so far. The population on Stinice has
lower density than the population on Turjak and individuals have larger head dimensions, and
distance between the tip of the snout and the front limbs
INFLUENCE OF NANOPARTICLES ON SOIL MICROBIOM
No full textZbog svojih specifičnih svojstva i širokog raspona primjene, nanočestice i nanomaterijali
danas se sve više primjenjuju u različitim poljima znanosti i granama ljudske djelatnosti
poput farmacije, medicine, poljoprivrede, tekstilne industrije i industrije boja, naftne industrije te prehrambene industrije. Posljedično tome povećava se broj nanočestica ispuštenih u
okoliš. S obzirom na njihov negativan utjecaj raste zabrinutost za ljude i okoliš od zagaĎenosti tla i vode. Nanočestice metala i metalnih oksida te nanočestice ugljikovih oksida i
nulto-valentnog ţeljeza mogu uzrokovati modifikacije mikrobioma, odnosno mikrobnih
aktivnosti u tlu te posljedično tome utjecati na plodnost i funkciju tla te biogeokemijske
cikluse, zbog čega je procjena nanotoksičnosti od iznimne vaţnosti.Due to its specific properties and wide range of applications, nanoparticles and nanomaterials are increasingly used today in various fields of science and branches of human
activity such as pharmaceuticals, agriculture, textile and dye industry, oil industry and food
industry. Consequently, the number of nanoparticles released into the environment increases. Given their negative impact, concerns for people and the environment are growing.
Nanoparticles of metals and metal oxides and nanoparticles of carbon oxides and zerovalent iron can modificate microbiome, more precisely, microbial activities in the soil and
consequently impact the amount of biogeochemical cycles – which is the reason why the
assessment of nanotoxicity is extremely important