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Genetic structure and diversity of the genus Chondrostoma (Actinopteri, Leuciscidae) in Croatia
No full textRijeke jadranskog slijeva kratke su i izolirane, što je potaklo alopatrijsku specijaciju i rezultiralo
visokom razinom endemizma. Endemske ribe roda Chondrostoma koje nastanjuju jadranski slijev su
vrste Chondrostoma knerii (Heckel, 1843), u hrvatskim krajevima poznata pod nazivom podustva, i
Chondrostoma phoxinus (Heckel, 1843), poznata kao podbila. Nedostatak podataka o njihovom
životnom ciklusu, ekološkim nišama i nedostatak samih kriterija za određivanje rijetkosti vrsta otežava
njihovu konzervaciju. Cilj je ovog istraživanja odrediti filogenetske odnose i genetsku raznolikost
podustve, podbile i samog roda Chondrostoma. Uzorci tkiva trbušne peraje su korišteni za umnažanje s
tri genska markera (citokrom b, beta-aktin, BMP 4) lančanom reakcijom polimeraze (PCR). Provedena
je filogenetska rekonstrukcija temeljena na sekvencama navedenih markera korištenjem sljedećih
metoda: metoda najveće parsimonije (MP), metoda najveće vjerojatnosti (ML) i metoda susjednog
povezivanja (MJ). Dobivena filogenetska stabla i mreže potvrdili su nekadašnji bliski kontakt hrvatskih
vrsta s talijanskom vrstom Chondrostoma soetta. Rodovi Achondrostoma, Iberochondrostoma i
Pseudochondrostoma relativno su nedavno odvojeni od roda Chondrostoma. Niska genska raznolikost
vrste C. knerii ukazuje na ugroženost ove vrste pod djelovanjem antropogenih čimbenika.The rivers of the Adriatic Basin are short and isolated, which encouraged allopatric speciation and
resulted in high degree of endemism. Endemic species of Chondrostoma genus which inhabit Adriatic
Basin are species Chondrostoma knerii (Heckel, 1843), known under the name Dalmatian nase in
Croatia, and Chondrostoma phoxinus (Heckel, 1843), known as Minnow nase. Lack of data about their
life cycle, ecological niches and lack of criteria for determining rare species makes their conservation
difficult. The aim of this study was to determine phylogenetic relationship and genetic diversity of
Dalmatian nase, Minnow nase and Chondrostoma genus in general. Samples of pelvic fins tissue were
used for multiplication of three genetic markers (cytochrome b, beta-actin and BMP4) using the
polymerase chain reaction (PCR). Phylogenetic reconstruction was done based on sequences of
aforementioned genetic markers using the methods of maximum parsimony, maximum likelihood and
median joining. Resulting phylogenetic trees and networks confirmed close contact of Croatian and
Italian species in the recent past. Achondrostoma, Iberochondrostoma and Pseudochondrostoma gemus
were relatively recently separated from the genus Chondrostoma. Low genetic diversity of
Synthesis of a diamide derivative of a disubstituted ferrocene with desmuramyl-peptide and mannose subunit
No full textU sklopu ovog diplomskog rada razvijen je sintetski put priprave amidnih, disupstituiranih
ferocenskih derivata s desmuramil-peptidnom (DMP) i manoznom podjedinicom. Derivati se
međusobno razlikuju u broju metilenskih skupina (n = 0-4) na poveznici između ferocenskog
i šećernog dijela molekule. U ovom je radu pripravljena ciljna molekula 11, s poveznicom od
četiri metilenske skupine i to vezanjem sljedećih strukturnih motiva: O-benzil zaštićene
manoze s glikolnom poveznicom, ferocenkarboksilne kiseline koja je esterificirana, a potom i
modificirana anhidridom glutarne kiseline u disusptituiranu ferocensku kiselinu 6, te
benzilom zaštićenog derivata DMP-a 7. Amidne veze su ostvarene pomoću pouzdane i
uhodane EDC/HOBt metode koja se često koristi u tu svrhu u peptidnoj kemiji. Sintetski put
priprave ciljne molekule završava korakom uklanjanja benzilne zaštite hidrogenolizom.
Provedena je detaljna strukturna karakterizacija svih sintetiziranih prekursora i konačnog
spoja (1H, DEPTQ NMR i IR spektroskopija, spektrometrija masa ESI-MS). Ovako
optimizirana metoda poslužit će za sintezu preostalih spojeva ove serije u budućim
istraživanjima čiji je konačni cilj ispitivanje njihove adjuvantske aktivnosti.In this Thesis the synthetic route for the preparation of amide, disubstituted ferrocene derivatives with desmuramyl peptide (DMP) and mannose subunit was optimized. The structures of final compounds vary in the number of methylene groups (n = 0-4) between the ferrocene and the sugar part of the molecule. Target molecule 11, which has four methylene groups, was prepared in this work by combining following structural motifs: O-benzyl protected mannose with glycolic linker, ferrocene carboxylic acid which was converted to ester first and subsequently modified with glutaric anhydride to disubstituted ferrocene acid 6, and benzyl protected DMP derivative 7. Amide bonds are formed by reliable and wellestablished EDC/HOBt method which is often used in peptide synthesis for this purpose. The synthetic route to target molecule ends with benzyl protection removal by hydrogenolysis. Structural characterization of all precursors as well as target compound was performed by 1H, DEPTQ NMR and IR spectroscopies as well as mass spectrometry (ESI-MS). Optimized synthetic route presented here will serve for the preparation of remaining compounds in this series. The final aim is the evaluation of their adjuvant activity
Analysis of channel sinuosity of the selected Drava River segments as an indicator of tectonic activity
No full textStrukturno geomorfološki procesi izrazito su bitni za oblikovanje reljefa, međutim determiniranje tektonski aktivnih područja, tj. aktivnih rasjeda izrazito je kompleksan problem. U novije vrijeme kao indikator pomaka i aktivnosti rasjeda može se koristi vijugavost rijeka. U ovome radu istražena je vijugavost toka rijeke Drave kako bi se istražila tektonska aktivnost. Na vijugavost toka rijeke Drave na području Hrvatske utječu tri rasjedne zone, Periadriatsko – Dravski rasjed, Dravski rasjed, te rasjedi na području Mađarske koji direktno presijecaju tok rijeke. Rijeka Drava svoj tok mijenja većinski pod utjecajem pomaka rasjeda koji su prostorno bliži njenom toku. Na sjeveru Hrvatske dolazi do izravnog presijecanja toka rijeke Drave rasjedima, pa taj dio toka ima veću vijugavost od ostalih dijelova Drave. Iz ovog rada je vidljivo da je vijugavost dobar indikator tektonske aktivnosti jer se povećava u blizini aktivnih rasjeda.Structural geomorphological processes are critically important for shaping the landscape; however, determining tectonically active areas, particularly faults, is a highly complex problem. Recently, river sinuosity has been used as a measure for identifying fault displacements and activities. In this work, the sinuosity of the Drava River was investigated to demonstrate the tectonic activity of faults. The meandering of the Drava River in the Croatian region is influenced by three fault zones: the Periadriatic-Drava Fault, the Drava Fault, and the normal faults in Hungary that directly intersect the river's course. The Drava River changes its course primarily under the influence of fault shifts that are spatially closer to its flow, while in Northern Croatia, the river's course is directly intersected, resulting in this section having greater sinuosity compared to other parts of the Drava's flow .It has been proven that sinuosity is a good indicator of tectonic activity, as it increases in areas where faults are tectonically active and exhibit greater fault plane displacements
Mineralogical and geochemical characteristics of bauxites from Košute and Gljev, Area of Sinj
No full textBoksiti su ležišta trošenja bogata aluminijem, a u suvremeno doba proučavaju se zbog prisutnosti
elemenata rijetkih zemalja. Osim ekonomske važnosti, indikatori su paleookoliša i paleoklime. U
radu su opisane mineraloške i geokemijske karakteristike boksita s lokaliteta Košute i Gljev,
nekadašnjih aktivnih kopova boksita u okolici grada Sinja. Za određivanje mineraloških
karakteristika, prikupljeni uzorci istraživani su optičkim metodama i metodom difrakcije
rendgenskih zraka na prahu (XRPD). Za kvalitativno određivanje kemijskog sastava korištena je
metoda pretražne elektronske mikroskopije (SEM) s energetsko disperzivnom spektroskopijom
(EDS) uz izradu kemijskih mapa, a za precizniju kvantitativnu analizu metoda masene
spektrometrije s induktivno spregnutom plazmom (ICP-MS). U podini krških boksita iz Košuta i
Gljeva su gornjokredni vapnenci, dok su im u krovini Promina naslage karbonatnog sastava.
Boksiti iz Košuta su gibbsitnog tipa, s visokih 24% silikatne komponente, a oni iz Gljeva su
böhmitno-gibbsitnog tipa, te s obzirom na omjer Al:Si do visokih 18:1 predstavljaju
najeksploatabilnije boksite u okolici Sinja. Količine REE u Gljevu prelaze 1500 ppm-a uz znatno
obogaćenje LREE. Neki uzorci iz Gljeva pokazuju više koncentracije itrija što vodi do viših
koncentracija HREE. Omjer La/Y u Košutama ukazuje na bazične uvjete trošenja (2,33-2,37), a
onaj u uzorcima iz Gljeva na kisele uvjete (0,60-0,85). Minerali nosioci REE su monacit i cirkon, a
značajne količine vjerojatno su adsorbirane na minerale glina.Bauxite is a lateritic mineral deposit rich in aluminium and potentially rich in Rare Earth Elements.
It has economic significance and provides insights into paleoenvironmental and paleoclimatic
conditions. The thesis aims to characterize the mineralogical and geochemical properties of bauxite
deposits in Košute and Gljev, once-active bauxite mines in the vicinity of the town of Sinj. In order
to determine mineralogical composition, samples are analysed with optical methods and X-ray
powder diffraction (XRPD). Scanning electron microscopy (SEM) with energy-dispersive X-ray
spectroscopy (EDS) is employed for chemical analysis and Inductively Coupled Plasma
Spectroscopy with mass spectrometry (ICP-MS) is used to determine the bulk chemical
composition of the samples. Both karstic bauxite deposits lie on Upper Cretaceous limestones and
are covered by Paleogene Promina carbonate beds. Bauxites from Košute are gibbsitic and contain
24% of silica while the bauxites from Gljev are boehmitic to gibbsitic and present the most
exploitable bauxites in the vicinity of Sinj. They exhibit a high Al:Si ratio, reaching up to 18:1. The
samples from Gljev show total REE abundances up to 1500 ppm with LREE enrichment. Some
Gljev samples exhibit elevated concentrations of yttrium, leading to higher concentrations of
HREE. The La/Y ratio in Košute suggests alkaline weathering conditions (2.33-2.37) and that in
the samples from Gljev to acidic conditions (0.60-0.85). REE-bearing minerals are monazite and
zircon but REEs are likely also absorbed on clay minerals
Thermodynamic and structural studies on the complexation of methyl esters of tetra and hexaphenylalanine with anions in acetonitrile
No full textCiklički peptidi predstavljaju posebno zanimljivu klasu supramolekulskih anionskih receptora zbog svoje raznolikosti i vrlo dobrih kompleksacijskih svojstava. Prvi korak sinteze cikličkih peptida je priprava njihovih linearnih analoga, a zatim se provodi reakcija ciklizacije. Najvažnija komponenta uspješne ciklizacije je konformacijska preorganizacija linearnog peptida u kojoj dolazi do približavanja N i C reaktivnih krajeva. Preorganizacija se može pospješiti korištenjem templatnih iona. U ovom radu istraženo je kompleksiranje metilnih estera linearnog tetra i heksafenilalanina s halogenidnim i oksoanionima u acetonitrilu. Konstante stabilnosti nastalih kompleksa određene su metodama 1H NMR spektroskopije, spektrofluorimetrije i spektroskopije cirkularnog dikroizma. Strukturne karakteristike anionskih kompleksa oba receptora istražene su simulacijama molekulske dinamike. Rezultati upućuju na to da su anioni koordinirani pomoću amidnih i amino protona peptida. Većina nastalih kompleksa je stehiometrije 1:1, osim u slučaju dihidrogenfosfata kod kojeg je uočena i stehiometrija 1:2 (receptor:anion)Cyclic peptides represent a particularly interesting class of supramolecular anion receptors due to their diversity and good complexation properties. The first step in the synthesis of cyclic peptides is the preparation of their linear analogues after which the cyclization is carried out. The most important factor for a successful cyclization is the conformational reorganization of the linear peptide, in which the N and C reactive ends approach each other. Reorganization can be enhanced using templating ions. In this work, the complexation of methyl esters of linear tetra and hexaphenylalanine with halide and oxoanions in acetonitrile was investigated. The stability constants of corresponding complexes were determined by 1H NMR spectroscopy, spectrofluorimetry and circular dichroism spectroscopy. The structural characteristics of the anionic complexes of both receptors were investigated by molecular dynamics simulations as well. The results indicate that the anions are coordinated by the amide and amino protons of the peptide. Most of the resulting complexes are of 1:1 stoichiometry, except in the case of dihydrogen phosphate, where a 1:2 stoichiometry (receptor:anion) was also observed
Mechanical responsiveness of crystals of coordination polymers of copper(II) halides with 4-cyanopyridine
No full textU ovom diplomskom radu sintetizirani su koordinacijski polimeri bakrovog(II) klorida i
bakrovog(II) bromida s 4-cianopiridinom (4-CNpy), [CuCl2(4-CNpy)2]n (1) i [CuBr2(4-
CNpy)2]n (2). Nastali produkti karakterizirani su infracrvenom spektroskopijom (IR),
termičkom analizom (TGA/DSC) te difrakcijom rendgenskog zračenja u polikristalnom uzorku
(PXRD). Kristali koordinacijskih polimera priređeni su metodom difuzije preko tekuće faze.
Priređenim igličastim kristalima ispitana je mehanička fleksibilnost uslijed primjene vanjske
mehaničke sile. Mehanički odziv kristala istražen je modificiranom metodom savijanja u tri
točke. Kristali spojeva 1 i 2 pokazali su mehanički potaknutu elastičnosti te je određen stupanj
elastičnosti. Ustanovljena mehanička fleksibilnost kristala spojeva 1 i 2 korelirana je s
međumolekulskim interakcijama ostvarenim u kristalnom pakiranju priređenih spojeva.This diploma thesis presents synthesis of coordination polymers of copper(II) chloride and
copper(II) bromide with 4-cyanopyridine (4-CNpy), [CuCl2(4-CNpy)2]n (1) and [CuBr2(4-
CNpy)2]n (2). The obtained compounds were characterized by infrared spectroscopy (IR),
thermal methods (TGA/DSC) and powder X-ray diffraction (PXRD). Crystals of the
coordination polymers were prepared using liquid-liquid diffusion method. The mechanical
flexibility of crystals was examined due to the application of an external mechanical force. The
mechanical responsiveness of crystals was investigated via modified three-point bending
experiments. Mechanically induced elasticity of crystals was observed and the extent of
elasticity was calculated. Mechanical flexibility observed on crystals of compounds 1 and 2
was correlated with intermolecular interactions in crystal packings of prepared compounds
The role of reactive oxygen species in response of potato (Solanum tuberosum) to infection with potato spindle tuber viroid (PSTVd)
No full textReaktivni kisikovi oblici (ROS) i salicilna kiselina (SA) igraju važnu ulogu u obrambenom
odgovoru biljaka na patogene. U ovom radu istražena je uloga ROS-ova i SA u interakciji biljaka
krumpira (Solanum tuberosum) i viroida vretenastog gomolja krumpira (PSTVd). Kvantificiran je
sadržaj vodikovog peroksida (H2O2) u listovima biljaka inokuliranih viroidom PSTVd i kontrolnih
biljaka linije divljeg tipa i transgenične linije NahG, te je određen učinak infekcije na akumulaciju
H2O2 u različitim vremenskim točkama nakon inokulacije. Istovremeno je analizirana ekspresija
gena uključenih u signalne puteve ROS-ova, uključujući gene za odabrane katalaze, peroksidaze i
proteinske kinaze aktivirane mitogenima (MAPK). Nadalje, uloga SA u interakciji krumpir-PSTVd
istražena je praćenjem učinka egzogenog tretmana s njenim sintetskim analogom, 2,6-
dikloroizonikotinskom kiselinom (INA), na akumulaciju H2O2 i promjene u ekspresiji gena
povezanih s antioksidacijskim odgovorom reguliranim SA-om. Rezultati ukazuju da odgovor
krumpira na infekciju viroidom PSTVd uključuje akumulaciju H2O2 i pokretanje antioksidacijskog
odgovora reguliranog SA-om koji dovodi do transkripcijske aktivacije peroksidaza i kinaza
MAPK. Opažen je pozitivan učinak tretmana s INA-om na imuni odgovor krumpira, posebice u
liniji NahG. Saznanja dobivena ovim istraživanjem pridonose boljem razumijevanju molekularnih
mehanizama uključenih u interakciju biljaka i viroida.Reactive oxygen species (ROS) and salicylic acid (SA) play a key role in plants' defense response
against pathogens. Herein, the role of ROS and SA in the interaction between potato (Solanum
tuberosum) plants and potato spindle tuber viroid (PSTVd) was investigated. The hydrogen
peroxide content (H2O2) in leaves of control and PSTVd-inoculated wild-type and transgenic NahG
plants was quantified at different time points after inoculation, and the effect of infection on H2O2
accumulation was determined. Simultaneously, the expression of genes involved in ROS signaling
pathways, including catalase, peroxidases and mitogen-activated protein kinases (MAPK), was
analyzed. Furthermore, the role of SA in the potato-PSTVd interaction was investigated by
monitoring the effect of exogenous treatment with 2,6-dichloroisonicotinic acid (INA), a synthetic
analog of SA, on H2O2 accumulation and changes in the expression of genes associated with SAregulated antioxidant response. The results indicate that the response of potato plants to PSTVd
infection involves accumulation of H2O2 and the activation of SA-regulated antioxidant responses,
leading to transcriptional activation of peroxidases and MAPK. A positive effect of INA treatment
on potato immunity, particularly in NahG lines was observed. The findings from this study
contribute to a better understanding of the molecular mechanisms underlying plant-pathogen
interactions
Mineralogical and geochemical properties of cave sediment from Đulin ponor
No full textSpeleološki objekti značajni su u istraživanjima okoliša jer predstavljaju zamke za sedimente te je zato u Đulinom ponoru uzorkovano 9 uzoraka sedimenta i 14 uzoraka plastike kako bi se istražio antropogeni utjecaj. Uzorci su analizirani sljedećim metodama: fazna analiza, FTIR – ATR spektroskopija, kalcimetrija, voltametrija i izdvajanje mikroplastike iz sedimenata SPT-om. U svim uzorcima sedimenta determinirane su mineralne faze kalcit i kvarc, a u nekim uzorcima još su determinirani feldspati, dolomit i ankerit. U reprezentativnom uzorku su determinirani minerali glina klorit, illit i kaolinit. Kalcimetrijom je određivan udio karbonatna za 10 uzoraka i rezultati ukazuju da se u prosjeku radi o sedimentima s visokim udjelom karbonata, a raspon je 25 % - 75 %. U svim uzorcima sedimenta pronađena je mikroplastika, a najveći je broj čestica mikroplastike u uzorku ĐULA SPT 2 s 341 česticom mikroplastike na 1 gram sedimenta. Od 14 uzoraka plastike determiniranih FTIR – ATR spektroskopijom, najzastupljeniji polimer je polistiren. Prema rezultatima voltametrije potencijalno toksični metal koji ima najveći afinitet adsorpcije na plastiku je cink.Speleological objects are important in environmental research because they represent traps for sediments, which is why 9 sediment samples and 14 plastic samples were collected in Đulin ponor in order to investigate anthropogenic influence. The samples were analyzed by the following methods: phase analysis, FTIR – ATR spectroscopy, calcimetry, voltammetry and separation of microplastics from sediments by SPT. The mineral phases calcite and quartz were determined in all sediment samples, and feldspar, dolomite and ankerite were also co-determined in some samples. The clay minerals chlorite, illite and kaolinite were determined in representative sample. Calcimetry was used to determine the percentage of carbonate for 10 samples, and the results indicate that, on average, these are sediments with a high percentage of carbonate, and the range is 25% - 75%. Microplastics were found in all sediment samples, and the largest number of microplastic particles was in the ĐULA SPT 2 sample with 341 microplastic particles per 1 gram of sediment. Of the 14 plastic samples determined by FTIR - ATR spectroscopy, the most represented polymer is polystyrene. According to the voltammetry results, the potentially toxic metal that has the highest adsorption affinity on plastic is zinc
Contemporary regional disparities and development perspectives of Lower Međimurje
No full textRazlike u stupnju regionalnog razvitka nekog područja, koje još možemo nazvati regionalnim disparitetima, sveprisutni su razvojni fenomen koji se veže uz brojne gospodarske, socijalne, morfološke, funkcionalne i ine aspekte razvoja određenog područja te su kao takve čest predmet interesa multidisciplinarnih istraživanja mnogih struka. Te se razlike ogledaju u neuravnoteženom demografskom, socioekonomskom i razvoju određenog prostora. U ovom su radu promatrani upravo takvi dispariteti na području Donjeg Međimurja. Najprije je izvršena suštinska demogeografska i socioekonomska analiza putem dostupnih podataka kako bi se utvrdili polovi razvoja. Potom su izvedeni još neki pokazatelji (kao što su podaci o stambenoj gradnji po općinama, indeks razvijenosti te indeks turističke razvijenosti) koji mogu ukazivati na određene disparitete u razvoju. Uslijedio je kvalitativni dio istraživanja u kojem su provedena dva polustrukturirana intervjua s načelnicima dviju općina (Strahoninec i Donja Dubrava) koje su bile reprezentativni primjerci svojih razvojnih polova. Također, proveden je i intervju s predstavnikom LAG-a Mura-Drava kao važnim ruralnim akterom. Na kraju je kao svojevrsni presjek svega izrađena i SWOT analiza područja. Istraživanjem je ustvrđeno da Donje Međimurje odlikuje značajan stupanj regionalnog disbalansa u razvoju te da se u budućnosti moraju provesti suštinske mjere kako bi se revitalizirao istok regije.Differences in the degree of regional development of an area, which we can also call regional disparities, are a common development phenomenon that is linked to numerous economic, social, morphological, functional and other aspects of the development of a certain area, and as such are a frequent subject of interest in multidisciplinary research by many professions. These differences are reflected in the unbalanced demographic, socioeconomic and other development of a certain area. In this paper, precisely such disparities were observed in the area of Donje Međimurje. First, an essential demogeographical and socioeconomic analysis was performed using the available data in order to determine the poles of development. Then some other indicators were derived (such as data on housing construction by municipality, development index and tourism development index) that may indicate certain disparities in development. This was followed by the qualitative part of the research, in which two semi-structured interviews were conducted with the mayors of two municipalities (Strahoninec and Donja Dubrava), who were representative examples of their development poles. Also, an interview was conducted with a representative of LAG Mura-Drava as an important rural actor. At the end, a SWOT analysis of the area was prepared as a kind of cross-section of everything. The research established that Donje Međimurje is characterized by a significant degree of reg. imbalance in development and that essential measures must be implemented in the future in order to revitalize the east of the region
Expression of circadian rhythm genes in HeLa cells treated with TNF-alpha and IFN-gamma
No full textCirkadijani ritam je unutrašnji biološki sat koji usklađuje fiziološke procese u organizmu s vanjskim podražajima kao što su svjetlost i temperatura. Cirkadijani ritam se održava dvjema regulacijskim povratnim petljama, kojima se posljedično reguliraju brojni fiziološki procesi, uključujući i imunosni sustav. Imunosni sustav ima bitnu ulogu u eliminaciji patogena i zaštiti organizma, a to provodi lučenjem različitih citokina, uključujući TNF-α i IFN-γ. Kako bi se bolje upoznao odnos gena cirkadijanog ritma i proupalnih citokina, u ovom je radu analizirana ekspresija ciljanih gena CLOCK, PER1, PER3, NPAS2, BMAL1, BMAL2 i CRY2 u stanicama HeLa tretiranih s 20 ng/ml i 50 ng/ml TNF-α nakon 24 sata i 48 sata i 30 ng/ml i 50 ng/ml INF-γ nakon 24 sata i 48 sati. RNA izolirana iz taloga stanica HeLa je reverzno transkribirana u cDNA te je lančanom reakcijom u stvarnom vremenu utvrđena razina ekspresije ciljanih gena. Dobivene vrijednosti ekspresije gena su uspoređene između tretiranih različitim koncentracijama TNF-α i IFN-γ i netretiranih stanica HeLa. Također, uspoređene su ekspresije ciljanih gena između stanica tretiranih s TNF-α i IFN-γ nakon 24 sata i 48 sati u svrhu provjere razlike u ekspresiji gena cirkadijanog ritma ovisno o duljini tretmana. Dobivene razlike u ekspresiji nisu bile statistički značajne što ukazuje na to da TNF-α i IFN-γ ne utječu na ekspresiju gena cirkadijanog ritma u stanicama HeLa tj. u stanicama koje nisu limfnog porijekla.Circadian rhythm is an internal biological clock that synchronizes physiological processes in the organism with external stimuli. This rhythm is maintained by two regulatory feedback loops, which consequently regulate numerous physiological processes, including the immune system. The immune system plays a crucial role in pathogen elimination and organism protection, achieved through cytokines, such as TNF-α and IFN-γ. To explore the interplay between circadian rhythm genes and pro-inflammatory cytokines, this study examined the expression of circadian rhythm genes CLOCK, PER1, PER3, NPAS2, BMAL1, BMAL2, and CRY2 in HeLa cells treated with 20 ng/ml and 50 ng/ml TNF-α for 24 and 48 hours, and with 30 ng/ml and 50 ng/ml IFN-γ for 24 and 48 hours. RNA isolated from the HeLa cell pellets was reverse transcribed and the expression levels of target genes were determined using quantitative polymerase chain reaction. Obtained gene expression values were compared between cells treated with different concentrations of TNF-α and IFN-γ and untreated HeLa cells. Additionally, gene expression levels were compared between cells treated with TNF-α and IFN-γ over 24 and 48 hours to assess differences in circadian rhythm gene expression depending on the treatment duration. There was no statistically significant difference in gene expression data, suggesting that TNF-α and IFN-γ have no impact on the expression of circadian rhythm genes in HeLa cells, e.g. cells that are not of lymphoid origin