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TAPHONOMIC AND PALAEOECOLOGICAL ALALYSIS OF THE LARG AVIFAUNAL REMAINS FROM THE ŠANDALJA II AND VLAKNO CAVES
No full textŠpilje Šandalja II u Istri i Vlakno na Dugom otoku važna su paleontološka nalazišta na kojima su pronađeni mnogobrojni fosilni, ali i arheološki ostaci iz gornjeg pleistocena i holocena. Rad je temeljen na anatomsko-taksonomskoj i tafonomskoj analizi uzoraka skeletnih ostataka velikih ptica prikupljenih za vrijeme iskopavanja samih lokaliteta. Na temelju rezultata dobivenih analizom ptičjih kostiju, utvrđeni su načini akumulacije u špiljama te paleoekološka i paleoklimatska situacija na prostoru Velike Jadranske ravnice u razdoblju gornjeg pleistocena (MIS2). U okolici špilje Vlakno u tom su razdoblju zastupljena dominantno vodena staništa, zatim otvorena staništa, stjenovita, mješovita te šumskih stepa. Dominantni čimbenici akumulacije u obje špilje su ljudi.Caves Šandalja II in Istria and Vlakno on Dugi Otok are important paleontological sites where numerous fossil and archaeological remains from the Upper Pleistocene and Holocene have been found. The study is based on anatomical-taxonomic and taphonomic analysis of samples of skeletal remains of large birds collected during excavations at the sites. Based on the results obtained from the analysis of bird bones, the modes of accumulation in the caves and the paleoecological and paleoclimatic conditions in the area of the Great Adriatic Plain during the Upper Pleistocene (MIS2) period have been determined. In the vicinity of Vlakno Cave during that period, predominantly aquatic habitats, followed by open habitats, rocky areas, mixed habitats, and forested steppes were represented. The dominant factors of accumulation in both caves are humans
Seismogeological interpretation of a basinal succession of a prograding delta (Pannonian, eastern part of the Drava depression)
No full textU ovom radu su analizirani i interpretirani seizmogeološki podatci iz pet bušotina sa područja istočne Hrvatske, radi boljeg razumijevanja geološke prošlosti i prepoznavanja geoloških resursa. Pri tome je korišten 3D seizmički volumen popraćen geofizičkim podatcima mjerenja u pet bušotina kao i geološki podatci prikupljeni istražnim radovima u bušotini. Od geofizičkih podataka u bušotinama za korelaciju istraživanih naslaga korištene su karotažne krivulje spontanog potencijala, RT otpora i prirodne gama radioaktivnosti. Interpretirano je devet horizonata od kojih je izdvojeno četiri kao relevantnih za istraživanje. Za četiri izdvojena horizonta napravljene su strukturne vremenske karte i karte Root mean square atributa i atributa koherencije. Napravljene karte pokazuju prisutnost kanala i taložnih formi okarakteriziranih kao sediment waves (pješčani valovi). Analizom podataka bušotinskih jezgri i krivulja spontanog potencijala dokazana je prisutnost pretežito lapora i turbidita na području istraživanja. Svi rezultati upućuju na postojanje rezervoarskih stijena koje bi mogle imati dobro zatvaranje.This work focuses on the analysis of seismo-geological data from five wells drilled in eastern Croatia, with the goal of better understanding the geological history and identifying geological resources in the area. The work presented in this thesis integrates 3D seismic data, well data and geological data from well cores. Well data used in the work are wellbore logs of spontaneous potential (SP), resistivity, and gamma ray. From nine horizons interpreted in this work, four were selected as important for the research. Structural time maps, Root Mean Square (RMS) maps, and coherence maps were made for each of the selected horizons. The maps show the existence of channels and sedimentary forms characterized as sediment waves. Core data and SP logs have proven the existence of mostly marls and turbidites in the research area. The results suggest the existence of reservoir rocks that could have a good seal in regard of potential hydrocarbon research
Masticatory and gustatory stimuli in burning mouth syndrome diagnosis and treatment
No full textSindrom pekućih usta (SPU) je idiopatski orofacijalni bolni poremećaj nejasne etiologije kojemu se danas pripisuje neuropatska geneza. Kako se dosadašnji pristupi liječenju SPU-a nisu pokazali uspješnijima od placeba, svrha ove studije je istražiti jedan poseban fenomen SPU-a koji do danas nije prihvaćen ni uključen u bilo koju od postojećih definicija, a to je da se u ovih bolesnika simptom žarenja privremeno smanjuje/povlači tijekom obroka. U istraživanje su uključena 52 ispitanika koji dolaze na pregled zbog spontanog žarenja usne šupljine sa zdravom oralnom sluznicom na mjestima prijave simptoma. Vrijednosti intenziteta simptoma zabilježene su numeričkom skalom za ocjenjivanje boli 0-10. Početak ublažavanja i povlačenja simptoma mjerio se zapornim satom nakon početka žvakanja komadića parafina te otapanja bombona u ustima. Po postizanju potpunog (ili maksimalnog) poboljšanja, mjerilo se vrijeme do povratka simptoma. Kod svih osim jednog ispitanika (98,1%) tijekom eksperimenta je došlo do poboljšanja dok je kod njih 44 (84,6%) postignuta privremena potpuna remisija na barem jedan od podražaja. Poboljšanje započinje unutar prve minute, dok se maksimalni učinak postiže tijekom tri minute. Povratak simptoma nakon završetka stimulacije započinje oko prve minute te se vraća na početnu razinu prije početka stimulacije unutar tri minute i 20 sekundi. Zaključno, ovaj fenomen jednostavno i pouzdano osigurava brzu i točnu dijagnozu SPU-a dok privremeno upravlja simptomima sa zasigurno najvišim postotkom učinkovitosti. Iz tog razloga, naši rezultati traže uključivanje istog u definiciju SPU-a.Burning mouth syndrome (BMS) is an idiopathic orofacial pain disorder of unclear etiology, now attributed to neuropathic genesis. Since previous approaches to treating BMS have not proven to be more successful than placebo, the study aimed to investigate a special phenomenon of BMS, not accepted or included in any of the existing definitions, that in these
patients the burning symptom temporarily reduces/disappears during meals. The study included 52 subjects examined for spontaneous burning pain of the oral cavity with healthy oral mucosa at sites where symptoms were reported. Symptom intensity was recorded using a numerical pain rating scale of 0-10. The beginning of alleviation and withdrawal of symptoms
was measured with a stopwatch after the beginning of chewing a piece of paraffin and dissolving a candy in their mouth. After achieving complete (or maximum) improvement, the time until the symptoms returned was measured. All but one subject (98,1%) improved during the experiment, while 44 of them (84,6%) achieved a temporary complete remission by at
least one stimulus. The improvement starts within the first minute, while the maximum effect is achieved within three minutes. The return of symptoms after the end of stimulation begins around the first minute and returns to the initial level within three minutes and 20 seconds. In conclusion, this phenomenon provides a quick and accurate diagnosis of BMS simply and reliably, while temporarily managing the symptoms with certainly the highest percentage of effectiveness. For this reason, our results call for its inclusion in the definition of BMS
Contemporary approach to open vestibuloplastics
No full textPretprotetska kirurgija definira se kao kirurški zahvat dizajniran za olakšavanje izrade proteza
ili za poboljšanje prognoze protetske opskrbe. Koštano preoblikovanje alveolarnog grebena je
doživotan proces kontinuiranog gubitka alveolarne kosti te predstavlja ozbiljan i čest problem,
posebice kod starijih osoba. Postoji velik broj operativnih metoda plastike vestibularne ili
lingvalne brazde s ciljem otklanjanja posljedica ravnomjerne atrofije alveolarnog nastavka i
stvaranja povoljnih uvjeta za izradu suficijentnog mobilnog nadomjestka.
PRF kako mu samo ime kaže “platelet-rich fibrin”, odnosno trombocitima bogat fibrin često
je korišten u regenerativnim zahvatima u dentalnoj medicini. Prisutnost PRF fibrinske mrežice
na početku cijeljenja rane stimulira angiogenezu u području rane. Ranijim istraživanjima
pokazalo se kako se tijekom tjedan dana iz PRF-a otpušta čak 6 faktora rasta stalne
koncentracije. Faktori rasta su endogene signalne molekule koje igraju važnu ulogu u
promicanju stanične diferencijacije i diobe stanica te na taj način reguliraju stanične odgovore
za proces cijeljenja rane. Glavne prednosti rada s PRF-om su jednostavnost pripravka preparata,
dostupnost svim pacijentima te minimalna trauma.
Nadalje, kako bi se smanjili nedostaci konvencionalnih zahvata vestibuloplastike, PRF
membrana može se koristiti za prekrivanje izloženog područja. Stoga ne bi bilo potrebe za
daljnjim uzimanjem kožnog ili mukoznog transplantata. Osim toga, epitelizacija rane je brža te
lakoća primjene ovog prirodnog biomaterijala može u konačnici povećati njegovu prihvaćenost
među kirurzima i pacijentima, dok pacijentima ostavlja manje komplikacija nakon operacije.Pre-prosthetic surgery is defined as a surgical procedure designed to facilitate the production
of prostheses or to improve the prognosis of prosthetic supply. Bone remodeling of the alveolar
ridge is a lifelong process, while continuous loss of alveolar bone is a serious and common
problem, especially in the elderly. There are several operative methods of vestibular or lingual
plastic surgery to eliminate the consequences of uniform atrophy of the alveolar process and
create favorable conditions for the production of a removable denture.
PRF as its name suggests "platelet-rich fibrin", is often used in regenerative procedures in
dentistry. The presence of PRF fibrin mesh at the beginning of wound healing stimulates
angiogenesis in the wound area. Previous research has shown that during the week, as many as
6 growth factors of constant concentration are released from the PRF. Growth factors are
endogenous signaling molecules that play an important role in promoting cell differentiation
and cell division and thus regulate cellular responses to the wound healing process. The main
advantages of working with PRF are the simplicity of preparation, availability to all patients
and minimal trauma.
Furthermore, in order to reduce the disadvantages of conventional vestibuloplasty procedures,
a PRF membrane can be used to cover the exposed area. Therefore, there would be no need to
take a skin or mucosal transplant. In addition, wound epithelialization is more rapid, while easy
application of this natural biomaterial can ultimately increase its acceptance among surgeons
and patients, while patients have fewer complications after surgery
Effect of copper oxide nanoparticles on oxidative stress in the freshwater alga Chlorella vulgaris
No full textBakar je važan metal sve zastupljeniji u obliku nanomaterijala u svakodnevnom životu. Intenzivna proizvodnja i korištenje materijala koji sadrže nanočestice bakra dovodi do otpuštanja tih čestica u okoliš što predstavlja potencijalnu opasnost za žive organizme zbog njihove visoke reaktivnosti i toksičnosti. Zelena alga Chlorella vulgaris je uvriježeni modelni organizam u ekotoksikološkim istraživanjima. U svom diplomskom radu analizirao sam utjecaj nanočestica CuO i Cu2O te iona bakra (CuSO4) u koncentracijama koje omogućuju preživljenje stanica alge C. vulgaris od 75% nakon 72 sata. Rezultati pokazuju da su nanočestice i ioni bakra značajno povećali razine reaktivnih oblika kisika, što je narušilo integritet biomembrana, dok su nanočestice CuO dodatno izazvale oštećenje proteina u stanicama. Nanočestice bakra nisu značajno utjecale na promjenu aktivnosti antioksidacijskih enzima, dok je ionski bakar značajno inhibirao njihovu aktivnost. Sadržaj reduciranog glutationa se povećao, a razina prolina smanjila nakon svih tretmana što ukazuje na pojačanu pripremu, ali i na kontinuiranu obranu stanica od oksidacijskog stresa. Nakon svih tretmana, ekspresija proteina Hsp70 se nije promijenila, dok se ekspresija proteina Hsp90 značajno smanjila. Izražena plazmoliza i destabilizacija stanične stijenke i membrane prati sve tretmane. Nanočestice CuO i Cu2O nakupljaju se na stanicama alge, u vakuoli te na tilakoidnim membranama. Tretmani s nanočesticama bakra imaju fitotoksičniji učinak na stanice alge u odnosu na tretman ionima bakra. Nanočestice Cu2O bile su fitotoksičnije na stanice alge u odnosu na nanočestice CuO.Copper is an important metal that is increasingly present in everyday life in the form of nanomaterials. The intensive production and use of materials containing copper nanoparticles leads to the release of these particles into the environment, posing a potential risk to living organisms due to their high reactivity and toxicity. The green alga Chlorella vulgaris is an established model organism in ecotoxicological research. In my master thesis, I investigated the influence of CuO and Cu2O nanoparticles and copper ions (CuSO4) in concentrations that enable 75% of the algal cells of C. vulgaris to survive after 72 hours. The results show that copper nanoparticles and ions significantly increase the level of reactive oxygen species, that damage the integrity of biomembranes, while CuO nanoparticles additionally cause protein damage in the cells. Copper nanoparticles had no significant effect changing the activity of antioxidant enzymes, while ionic copper significantly inhibited their activity. Reduced glutathione levels increased, and proline levels decreased after all treatments, indicating improved priming but also continuous defense of cells against oxidative stress. After all treatments, the expression of the Hsp70 protein did not change, while the expression of the Hsp90 protein decreased significantly. Pronounced plasmolysis and destabilization of the cell wall and membrane were observed after all treatments. CuO and Cu2O nanoparticles accumulate on algal cells, in the vacuole and on thylakoid membranes. Copper nanoparticle treatments have a more toxic effect on algal cells compared to copper ions. Cu2O nanoparticles were more phytotoxic to algal cells compared to CuO nanoparticles
Učinci povišene temperature vode i onečišćujućih tvari na nekoliko bioloških obilježja ličinki tulara
No full textUrbanization and inadequate wastewater treatment contaminate freshwater ecosystems with
complex chemicals, which, along with climate change, threaten freshwater insects. To assess
these impacts, we conducted a 21-day microcosm experiment simulating a simplified
freshwater food web containing moss and larvae of two caddisfly species, Drusus croaticus
and Allogamus uncatus. The experiment included control (C), increased temperature (T2 = C +
4 °C), emerging contaminants mixture (EC), and multiple stressor treatment (MS = EC + T2).
We analysed caddisfly mortality, body weight, locomotor activity (distance moved), and
compared species-specific effect of selected stressors. ECs exposure increased average body
weight in both species with contrasting effects on locomotor activity, increasing larval average
distance moved in D. croaticus but reducing it in A. uncatus. T2 treatment caused the highest
mortality for D. croaticus larvae, while the mortality of A. uncatus larvae was similar in all
treatments. MS treatment significantly impacted D. croaticus larvae behaviour, leading to
reduced larval average distance moved compared to other treatments, highlighting the
complexity of multiple stressor interactions. The observed interspecies variability emphasizes
the importance of considering species-specific characteristics in ecological risk assessments.
These findings offer insights into how multiple stressors may impact caddisfly populations,
crucial members of aquatic ecosystems.Urbanizacija i neadekvatna obrada otpadnih voda onečišćuju slatkovodne ekosustave smjesama
onečišćivača, koji s klimatskim promjenama ugrožavaju slatkovodne kukce. U svrhu procjene
tih utjecaja, proveli smo 21-dnevni eksperiment stimulirajući pojednostavljenu slatkovodnu
hranidbenu mrežu s mahovinom i ličinkama dviju vrsta tulara, Drusus croaticus i Allogamus
uncatus. Eksperiment je uključivao kontrolnu skupinu (C), tretman s povišenom temperaturom
(T2 = C + 4 °C), smjesom onečišćivača (EC) te višestrukim stresorima (MS = EC + T2).
Analizirali smo smrtnost, srednju tjelesnu težinu, lokomotornu aktivnost (srednja prijeđena
udaljenost) tulara te usporedili učinak odabranih stresora specifično na svaku vrstu. Izloženost
smjesi onečišćivača povećala je prosječnu tjelesnu težinu u obje vrste, s kontrastnim učincima
na lokomotornu aktivnost, povećavajući prosječnu prijeđenu udaljenost ličinki D. croaticus te
je smanjujući za ličinke A. uncatus. Povišena temperatura (T2) uzrokovala je najveću smrtnost
ličinki D. croaticus, dok je smrtnost ličinki A. uncatus bila slična u svim tretmanima. Tretman
višestrukim stresorima značajno je utjecao na ponašanje ličinki D. croaticus, smanjujući
prosječnu prijeđenu udaljenost u usporedbi s kontrolnom skupinom i drugim tretmanima,
naglašavajući složenost interakcija višestrukih stresora. Uočena varijabilnost među vrstama
naglašava važnost razmatranja karakteristika specifičnih za pojedinu vrstu. Naša otkrića
pružaju uvid u utjecaj višestrukih stresora na populacije tulara, ključne članove vodenih
ekosustava
Synthesis, cyclization and characterization of catalytic peptide CG11
No full textKatalitički peptidi su kratke sekvence aminokiselina koje mogu katalizirati
specifičnu kemijsku reakciju. Katalitički peptidi često su inspirirani aktivnim
mjestima enzima. Katalitička aktivnost enzima proizlazi iz specifičnog
rasporeda aminokiselinskih ostataka unutar njihove trodimenzionalne
strukture, što im omogućuje interakciju sa supstratima na precizan i
selektivan način. Katalitički peptidi mogu se koristiti kao katalizatori za
organske ili anorganske reakcije i za asimetrične transformacije/kiralne
katalitičke reakcije. Kratki katalitički peptidi karakterizirani su
konformacijskom fleksibilnošću i mogu se lako prilagoditi i funkcionalizirati
na različite načine. Njihova struktura koja se sastoji od monomera
aminokiselina dopušta nebrojene mogućnosti u dizajnu katalitičkih peptida.
Ipak, odnos između sekvence aminokiselina peptida i njegove katalitičke
aktivnosti nije u potpunosti shvaćen. Unatoč svom velikom potencijalu,
postoji nekoliko izazova, poput njihove niske stabilnosti i niske
selektivnosti.
Ovaj rad bavi se razotkrivanjem odnosa strukture i aktivnosti kratkog
katalitičkog peptida, CG11, i modifikacijom njegove strukture sa svrhom
poboljšanja katalitičke učinkovitosti. Ciklizacija linearnog CG11 peptida služi
kao jednostavna, ali potentna modifikacija koja nudi poboljšanu rigidnost i
stabilnost. Uz stalna istraživanja i razvoj novih peptida koji se mogu podesiti
za određene funkcije, katalitički peptidi mogu se koristiti kao visoko
učinkoviti biokatalizatori u kemijskoj i biotehnološkoj industriji.Catalytic peptides are short sequences of amino acids capable of catalyzing
a specific chemical reaction. Catalytic peptides are often inspired by enzyme
active sites. Enzyme catalytic activity arises from the specific arrangement
of amino acid residues within its three-dimensional structure, which allows
it to interact with substrates in a precise and selective manner. Catalytic
peptides can be utilized as catalysts in organic and inorganic reactions and
for asymmetric transformations/chiral catalytic reactions. Short catalytic
peptides are characterized by conformational flexibility and can be easily
tuned and functionalized numerous ways. Their structure consisting of
monomers of amino acids allows countless possibilities in the design of
catalytic peptides. Still, the relationship between the amino acid sequence
of a peptide and its catalytic activity is not entirely understood. Despite their
great potential, they face several challenges, such as low stability and low
selectivity.
This thesis deals with unraveling the structure–activity relationship of a
short catalytic peptide, CG11, and the modification of its structure with the
goal to achieve better catalytic efficiency. Cyclization of the linear CG11
peptide serves as a straightforward but powerful modification that offers
improved rigidity and stability. With continuing research and development
of novel peptides that can be finely tuned for specific functions, catalytic
peptides can be employed as highly efficient biocatalysts in chemical and
biotechnological industry
MARICA, TONKA AND IVE - MALE AND FEMALE PERSONAL NAMES IN POP AND POPULAR CROATIAN MUSIC
No full textOd prvih društvenih zajednica do današnjih dana, osobna su imena važan kako društveni tako i leksički, ali i kulturalni koncept. Primarno uvedena kako bi se članovi zajednice međusobno razlikovali postala su važan znak i obilježje pripadnosti i identiteta pojedinca. Veza između imena i pojedinca vrlo je snažna, u nekim kulturama smatrana je i sudbonosnom. Dokaz je tomu i latinska uzrečica Nomen est omen, koja je u hrvatskom jeziku poznatija pod izrazom Ime je znak, upotrebljavana kada se želi naglasiti usklađenost značenja imena s karakternim osobinama osobe koja ga nosi. Kada su, vremenom, društvene zajednice postale sve brojnije i imena nisu bila dovoljna oznaka razlikovanja, osobnim se imenima počinju dodavati nadimci, imena koja nisu službena, već nadjenuta od zajednice u kojoj pojedinac boravi. Ta su imena većinom inspirirana vrlinama i manama pojedinca, njegovim fizičkim obilježjima, mjestom iz kojeg dolazi ili poslom kojim se bavi. Osobni su nadimci prelazili u obiteljske nadimke te konačno u prezimena. U ovom će radu fokus biti na imenima i nadimcima spomenutim u pjesmama izvedenim na Splitskom festivalu u razdoblju od 1962. do 1992.From the first social communities to the present day, personal names are an important social and lexical concept, as well as a cultural concept. Primarily introduced in order to differentiate community members from each other, they have become an important sign and characteristic of individual belonging and identity. The connection between a name and an individual is very strong, in some cultures it is considered fateful. Proof of this is the Latin saying Nomen est omen, which in croatian is better known as the expression Ime je znak, used when one wants to emphasize the harmony of the meaning of the name and the character traits of the person who bears it. When, over time, social communities became more and more numerous and names were not a sufficient mark of distinction, nicknames began to be added to personal names, names that are not official, but given by the community in which the individual resides. These names are mostly inspired by the virtues and flaws of an individual, his physical characteristics, the place he comes from or the work he does. Personal nicknames
became family nicknames and finally surnames. In this paper, the focus will be on the names and nicknames mentioned in the songs performed at the Split Festival in the period from 1962 to 1992
High-angle-of-attack aerodynamics model for modern fighter aircraft
No full textU ovom diplomskom radu modeliran je slom uzgona u Simulink-u za avion IR-1 nalik na Dassault Rafale. Na temelju literature, odabrani su koeficijenti potrebni za opisivanje modela. Implementirani su koeficijenti uzgona, otpora, momenta propinjanja te bočni koeficijenti skretanja i valjanja za velike napadne kutove, od 10 do 60 stupnjeva. Proveden je eksperiment za analizu rezultata s pilotom u petlji. Postojeći model zrakoplova IR-1, nakon modifikacija uvedenih za slom uzgona analiziran je na simulatoru leta na uzorku od 10 ispitanika. Za potrebe eksperimenta, kandidati su dobili dva zadatka izvlačenja zrakoplova iz sloma uzgona. Prvi zadatak sastoji se od prilaska slomu uzgona te neposredno nakon dolaska u slom uzgona, odnosno trenutka u kojem napadni kut dođe do 25 stupnjeva, izvlačenje iz ekstremne situacije. Sljedeći zadatak je ponovno približavanje slomu uzgona te nakon ulaska u duboki slom uzgona za što se smatra situacija u kojoj je napadni kut već prešao iznos od 30 stupnjeva, slijedi izvlačenje aviona iz sloma uzgona. Svaki od kandidata je ispunio NASA – Task Load Index upitnik i ocijenio upravljivost modela po Cooper-Harper ljestvici za oba zadatka. Nakon eksperimenata provedena je subjektivna i objektivna analiza rezultata. Analize rezultata uključuju i provjeru zaključaka dobivenih iz analize ravnotežnog leta i analize valjanja zrakoplova za rezultate dobivene proračunom.In this thesis, stall was modeled in Simulink for IR-1, aircraft similar to the Dassault Rafale. Based on already obtained data, coefficients nedeed for creating the model were chosen. The lift coefficients, drag coefficients and pitch moment coefficients among with lateral coefficients for roll and yaw, are implemented in the Simulink model for high angles of attack, from 10 to 60 degrees. After collecting the data and modifying the model, an experiment was conducted with a pilot in the loop. The existing IR-1 aircraft model, was analyzed on a flight simulator on a sample of ten subjects. For the purposes of the experiment, candidates were given two tasks of saving the aircraft from stall conditions. The first task consists of approaching the stall and immediately after the signal, i.e. the moment when the angle of attack reaches 25 degrees, getting out of the extreme situation. The following task is to approach to deep stall conditions, and right after the angle of attack has reached 30 degrees, retract the aircraft. Each of the candidates completed the NASA Task Load Indeks questionnaire and rated the manouverability of the model according to the Cooper-Harper scale for both tasks. After the experiments, a subjective and objective naalysis of the results as carried out. The analysis of the results includes the verification of the conclusions obtained from the trim flight analysis and the analysis of lateral aerodynamics from the calculations done before experiments
Effect of exposure to α-cypermethrin on markes of oxidative stress in pregnant female rats
No full textPiretroidi su skupina insekticida koja ima široku primjenu u agronomiji, veterini i kućanstvu. Utvrđeno je kako piretroidi mogu djelovati kao hormonski otrovi, a posredni mehanizam između izloženosti hormonskim otrovima i njihovim učincima na ljudsko zdravlje može biti oksidacijski stres, karakteriziran poremećajem ravnoteže prooksidansa i antioksidansa. Najpoznatiji sintetski piretorid je α-cipermetrin koji se zbog svoje lipofilne prirode nakuplja u masnom tkivu, jetri i mozgu te može ući u posteljicu. Cilj ovog istraživanja bio je odrediti utjecaj izloženosti α-cipermetrinu na indukciju oksidacijskog stresa mjerenjem određenih markera u tkivima ženki štakora izloženih navedenom pesticidu u dozama 1, 10 i 19 mg kg−1 dan−1 za vrijeme gestacije. U krvi, mozgu i posteljicama ženki štakora određivani su koncentracija malondialdehida tekućinskom kromatografijom visoke djelotvornosti, a količina reaktivnih kisikovih spojeva i reduciranog glutationa te katalitička aktivnost enzima katalaze, superoksid dismutaze i glutation peroksidaze spektrofotometrijski. Poremećaj oksidacijsko- antioksidacijske ravnoteže uočen je u svim analiziranim tkivima i to ponajviše nakon izloženosti α-cipermetrinu u dozi od 1 mg kg-1. Indukcija oksidacijskog stresa u mozgu gravidnih štakorica ukazuje na moguća fiziološka oštećenja majke, a u posteljici da postoji mogućnost i za poremećaj funkcije endokrinog sustava.Pyrethroids are a group of insecticides that are widely used in agronomy, veterinary medicine and household. It has been recognized that pyrethroids can act as endocrine disruptors, and the intermediate mechanism of exposure and effect on human health can be oxidative stress, characterized by a disturbance in the balance of prooxidants and antioxidants. The well known synthetic pyrethroid is α-cypermethrin, which due to its lipophilic nature accumulates in fatty tissue, liver and brain, but there is also the possibility of its passage through the placenta. The aim of this research is to determine the impact of exposure to α-cypermethrin on the induction of oxidative stress by measuring respective markers in the tissues of female rats exposed to the pesticide in doses of 1, 10 and 19 mg kg-1 day-1 during gestation. We analyzed the concentration of malondialdehyde by high-performance liquid chromatography, and the amount of reactive oxygen species, reduced glutathione, and the catalytic activity of the enzymes catalase, superoxide dismutase and glutathione peroxidase by spectrophotometry in the blood, brain and placentas of female rats. Disturbance of the oxidation-antioxidant balance was observed in all analyzed tissues, mostly after exposure to α-cypermethrin at a dose of 1 mg kg-1. The induction of oxidative stress in the brain of pregnant rats indicates possible physiological damage to the mother, and in the placenta, potential for disruption of the function of the endocrine system