Repository of the Department of Marine Studies at the University of Split
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Application of stichodactyla toxin in the treatment of autoimmune diseases
No full textStichodactyla helianthus (Ellis, 1768) je vrsta vlasulje prisutna u Karipskom moru. Sadrži neurotoksine koji prvenstveno služe za obranu od predatora. Proučavanje peptida ShK iz ove vrste pokazalo je da osim toksičnog učinka postoji i moguća terapeutska primjena. Stichodactyla toksin ShK djeluje tako da blokira Kv1.3 kanale i zbog toga može suzbiti imunološke odgovore bitne za patogenezu brojnih bolesti kao što su multipla skleroza, psorijaza, reumatoidni artritis, itd. Napravljeno je mnogo sintetičkih analoga ovoga spoja od kojih su najbitniji ShK-Dap22, ShK-F6CA, D-allo-ShK, ShK-170, ShK-192 te ShK-186 koji je pod nazivom dalazatid ušao u kliničko ispitivanje za liječenje plak psorijaze.Stichodactyla helianthus (Ellis, 1768) is a species of anemone present in the Caribbean Sea. It contains neurotoxins that are primarily used as a defense against predators. Investigation of the ShK peptide, derived from this species, showed that besides the toxic effect there is also a possible therapeutic application. Stichodactyla toxin ShK works by blocking Kv1.3 channels and therefore can suppress the immune responses essential for the pathogenesis of numerous diseases such as multiple sclerosis, psoriasis, rheumatoid arthritis, etc. Many synthetic analogues of this compound have been made, the most important of which are ShK-Dap22, ShK-F6CA, D-allo-ShK, ShK-170, ShK-192, and ShK-186 now called dalazatide, which has entered clinical trials for treating plaque psoriasis
The effects of lost fishing gear on the biodiversity of the early development stages of sea organisms
No full textU ovom radu analiziran je utjecaj izgubljene ribolovne mreže gavunare na bioraznolikost morskih organizama i njihovih razvojnih stadija (engl. ghost fishing). Praćeno je i pomicanje mreže uzrokovano različitim vremenskim i hidrografskim promjenama te utjecaj stupnja obraštaja na bioraznolikost morskih organizama. Istraživanje je provedeno u razdoblju od 24. studenog 2017. godine do 28. siječnja 2018. godine, tijekom kojeg je izvršeno 10 zarona autonomnim ronjenjem. Korištena mreža gavunara je duga 65 metara, a visoka 5 metara, dok joj je promjer oka 10 milimetara i debljina konca 210/2. Postavljena je na dubini od 15 do 17 metara. Mreža je utjecala na 479 organizama. Od 229 jedinki koje su pronađene zapletene u mreži, 225 (98%) su bile ribe (Pisces), 3 (1,3%) bodljikaša (Echinodermata), te 1 (0,7%) rak (Crustacea). Zabilježena su 194 organizma koja su koristila mrežu kao stanište i mjesto za hranjenje, od kojih su 40% bili mekušci (Mollusca), 77 jedinki, 39% bodljikaši (Echinodermata) sa 75 jedinki, te 21% riba (Pisces) odnosno 42 jedinke. Među 229 zapletenih organizama, 2 su bila u mlađem razvojnom stadiju. Dvije zabilježene juvenilne ribe su vrste pauk bijelac (T. draco) i lokarda (S. japonicus). Među 194 organizma koji su koristili mrežu kao stanište i mjesto za hranjenje, 24 su (12%) juvenilna primjerka. Za 92% mlađih razvojnih stadija kojima je mreža poslužila kao stanište ili mjesto za hranjenje su bile ribe (Pisces), točnije 22 jedinke, dok su ostalih 8% (2 jedinke) bili puževi (Gastropoda). Pronađeno je i 56 nakupina jajašaca.This paper analyzes the impact of the lost gill net on the biodiversity of marine organisms and their developmental stages. The impact of different weather changes on the nets movements, as well as the effect of the degree of cultivation on marine organisms was monitored. The research was conducted in the period from 24.11.2017. until 28.01.2018. during which 10 dives were carried out with scuba gear. Used gill net was 65 meters long and 5 meters high, with a 10 millimeter diameter of the eye and 210/2 thread thickness. The net was left at depths of 15 to 17 meters, and affected 479 organisms. Out of 229 individuals found in the net, 225 (98%) were fish (Pisces), 3 (1.3%) echinoderms (Echinodermata) and one (0.7%) crustacean (Crustacea). 194 organisms used the net as a habitat and a feeding site, 40% of which were molluscs (Mollusca), with 77 individuals, 39% echinoderms with 75 individuals, and 21% fish (Pisces) with 42 individuals. Out of 229 caught organisms, 2 were in the younger stage of development. Two noted juvenile fishes are of the species of Trachinus draco and Scomber japonicus. Among the 194 organisms that used the net as a habitat and a feeding site, 24 (12%) were juvenile specimens. 92% of the younger developmental stages that used the net as a habitat or a place for feeding were fish (namely, 22 individuals), while the other 8% (2 individuals) were snails (Gastropoda). 56 egg clusters were also found
The distribution of heterotrophic bacteria in the deep Adriatic
No full textU ovom radu je detaljno prikazana raspodjela heterotrofnih bakterija, heterotrofnih nanoflagelata, skupina heterotrofnih bakterija s visokim i niskim udjelom nukleinske kiseline u ukupnoj populaciji, bakterijske proizvodnje te su određeni mehanizmi kontrole bakterijske populacije na tri postaje smještene u otvorenom dijelu srednjeg i južnog Jadrana. Istraživanje je provedeno sezonski, od ožujaka do studenog 2013. godine. Analizom podataka utvrđeno je da su istraživana područja izrazito oligotrofnog karaktera. Također je utvrđeno prevladavanje skupine bakterija s visokim udjelom nukleinske kiseline na istraživanim postajma. Najveće vrijednosti bakterijske proizvodnje utvrđene su u proljetnim mjesecima. Heterotrofne bakterije su bile kontrolirane predacijom od strane heterotrofnih nanoflagelata na svim istraživanim postajama.In this thesis, the distribution of heterotrophic bacteria, heterotrophic nanoflagellates, the percentage of high nucleic acid and low nucleic acid bacteria in the total population of heterotrophic bacteria, bacterial production and main control mechanism of heterotrophic bacteria on three stations placed in the middle and south Adriatic Sea were studied. The research was carried out from March to November 2013. Following the analysis of the data, the researched area was characterized as oligotrophic. We determined the higher presence of the high nucleic acid bacterial group. The higher values of bacterial production were determined during the spring. Heterotrophic bacteria were controlled through the predation by heterotrophic nanoflagellates on all studied stations
pH and temperature influence on the content of domoic acid in warty venus Venus verrucosa (Linnaeus, 1758)
Get PDFDomoična kiselina (DK) je neurotoksin i uzročnik je ASP (Amnesic Shellfish Poisoning) otrovanja ljudi. Kvantitativno određivanje domoične kiseline u školjkašima je važno u prevenciji trovanja ASP-om koje bi moglo nastati nakon konzumacije toksičnih školjkaša. U ovom istraživanju ispitana je stabilnost domoične kiseline u ekstraktu brbavica (Venus verrucosa) pri vrijednostima pH od približno 1 i 3 te temperaturama od 37oC i 90oC. Domoična kiselina je određivana metodom tekućinske kromatografije i masene spektrometrije (LC-MS/MS) u metanolskom ekstraktu ukupnog jestivog mekog tkiva brbavica. Rezultati su ukazali da temperatura ekstrahiranja domoične kiseline ne utječe značajno na stabilnost domoične kiseline, dok vrijednost pH utječe. Naime, ustanovljen je utjecaj nižeg pH (1,09 – 1,50) pri kojem srednja vrijednost iskorištenja domoične kiseline iznosi 72,1 %, dok pri pH 3 (3,01 – 3,35) iznosi 99,6 % .Domoic acid (DA) is a neurotoxin that causes ASP poisoning (Amnesic Shellfish Poisoning). Quantitative determination of domoic acid in shellfish is important in the prevention of ASP poisoning that could occur after the consumption of toxic bivalve molluscs. In this study, the stability of domoic acid in clams (Venus verrucosa) extract was tested at pH values of approximately 1 and 3 and at 37oC and 90oC. Domoic acid was determined by liquid chromatography and mass spectrometry (LC-MS/MS) in a methanol extract of total edible shellfish soft tissue. Domoic acid extraction temperature does not significantly affect the stability of the domoic acid while the pH is affected. The effect of lower pH (1.09 - 1.50) was established at which the mean value of domoic acid recovery was 72.1%
Bottom trawl selectivity on the deep-water rose shrimp Parapenaeus longirostris (Lucas, 1846)
No full textU ovom radu simuliran je bijeg kozice (Parapenaeus longirostris) iz vreće pridnene povlačne mreže koće. Za potrebe eksperimenta uzorkovano je 135 primjeraka kozice duljine karapaksa od 9 do 32 mm. Testom propadanja se svaka uzorkovana jedinka kozice pokušala provući kroz šesnaest testnih oka veličine 52 mm i kutova otvora od 15° do 90°, laserski urezanih u plastičnu ploču debljine 5 mm. Dobiveni podatci omogućili su kreiranje selekcijske krivulje za svako testno oko. Usporedbom referentne selekcijske krivulje s krivuljama testa propadanja, identificirani su realni načini bijega kozice kroz vreću mreže. Od ukupno dvanaest testiranih načina bijega, utvrđeno je da ih je samo šest realno.This thesis describes the escapement behaviour of the deep-water rose shrimp (Parapenaeus longirostris) from the demersal trawl codend. For the experiment, 135 individuals of the deep-water rose shrimp ranging from 9 to 32 mm carapace length were collected. Using the fall-through experiments, a total of 16 meshes were tested. The meshes were 52 mm in size, with mesh opening angles ranging from 15° to 90°. The obtained results allowed creation of the selection curve for each mesh opening. By comparing the reference fall-through curves with experimentally obtained selection curve it was possible to identify 6 realistic modes of escapement utilized by the deep water rose shrimp to escape from the demersal trawl codend
Facultative and obligatory relationships between fishes and sponges
No full textU ovom radu opisani su fakultativni i obligatni odnosi riba i spužvi. Spužve su sesilni filtratorski organizmi s jednostavnom staničnom građom. Unatoč ranjivosti i neprisutnosti pravog obrambenog mehanizma spužve uspješno izbjegavaju predatore. One čine zajednice s različitim skupinama beskralježnjaka i riba, koji žive na površini i u unutrašnjosti spužve. Ti organizmi imaju određene strukturalne prilagodbe za život unutar spužvi, od kojih je najvažnija mala veličina tijela. Malo toga je poznato o hranidbi riba u obligatnim zajednicama sa spužvama. Simbionti okupiraju spužve vođeni razlikama u obojanosti spužvi. Nedostatak prikladnih spužvi na nekom području za posljedicu ima izostanak nekih vrsta riba koje žive u zajednici sa spužvama. Osim obligatnog odnosa, razne ribe koriste spužve kao zaštićene i visoko učinkovite inkubatore svojih jaja. Klasificirano je ukupno 20 fakultativnih simbionata spužvi, koji provode barem jedan dio svog života u cjevastim spužvama. Većina fakultativnih odnosa riba i spužvi je slabo poznata.In this paper obligatory and facultative partnerships between fishes and sponges are described. Sponges are sessile filter-feeders with simple cellular structure. Despite the vulnerability and inadequacy of the sponge defense mechanism, they successfully avoid predators. They form associations with different groups of invertebrates and fish, living on the surface and in interior of the sponges. These organisms have certain structural adaptations to life within the sponge, the most important of which is small size. Little is known on feeding of fish in the obligatory associations with sponges. Symbionts occupy sponges led by differences in sponge color. The lack of suitable sponges in certain areas result in the lack of the fish species living in the community with sponges. In addition to the obligatory relationship, various fish use sponges as the well protected and highly effective incubators of their eggs. A total of 20 nonobligatory sponge symbionts have been classified, which spend at least a portion of their lives in tubular sponges. Most of the facultative relationships between fishes and sponges are poorly understood
Green fluorescent protein
No full textoai:repozitorij.more.unist.hr:morest_259U ovom radu su predstavljene karakteristike i primjene zelenog fluorescentnog proteina. Zeleni fluorescentni protein (GFP, engl. green fluorescent protein) izoliran je iz meduze Aequorea victoria koja je rasprostranjena duž zapadne obale Sjeverne Amerike. GFP ima oblik cilindra, tzv. formu β-limenke. Ciklizacijskim reakcijama unutarnjih lanaca β ploče i aminokiselina stvara se kromofor koji daje boju proteinu. Različitim mutacijama stvarane su različite varijante odnosno derivati GFP-a pa imamo plavi fluorescentni protein, cijan fluorescentni protein i žuti fluorescentni protein. Primjena GFP-a je raznolika, pa se isti koristi u dijagnostici tumora, kao reporter transkripcijske regulacije, kao biosenzor, pri vizualizaciji proteina u stanici te u istraživanju primarnih staničnih funkcija. Zbog svoje široke primjene nedvojbeno je da će se daljnjim istraživanjima poboljšati karakteristike GFP-a i njegovih derivata i tako proširiti područje primjene.In this thesis, characteristics and applications of green fluorescent protein are presented. The green fluorescent protein (GFP) is isolated from the jellyfish Aequorea victoria that is widespread along the west coast of North America. GFP has cylinder shape also referred to as β-can structure. Cyclization reactions between inward-facing sidechains and amino acids creates chromophore that gives protein it's colour. Different mutations made different derivatives of GFP so we have blue fluorescent protein, cyan fluorescent protein and yellow fluorescent protein. Applications of GFP are diverse, in tumour diagnostics, as transcriptional regulation reporter, biosensor, when visualizing proteins in the cell, in research of primary cell functions, among others. It is undoubtable that further research will improve characteristics of GFP and its derivatives and thus extend the scope of their application
Banded murex Hexaplex trunculus as bioindicator of contamination in the Adriatic
Get PDFVolak Hexaplex trunculus se često koristi za praćenje onečišćenja morskog okoliša organokositrovim spojevima, u prvom redu tributilkositrom (TBT). Radi se o vrsti koja razvija imposeks već pri niskim razinama onečišćenja TBT-om. U ovoj disertaciji predstavljeni su rezultati istraživanja povezanosti imposeksa kod volka H. trunculus i onečišćenja TBT-om provedenih na području srednjeg dijela hrvatskog Jadrana na 7 postaja tijekom 2014. godine i 12 postaja tijekom 2015. godine. Kod svih istraživanih populacija zabilježena je pojava imposeksa, a mjerenjem masenog udjela TBT-a u tkivu volka H. trunculus i sedimentu potvrđena je i prisutnost onečišćenja TBT-om. Istraživanjem provedenim 2014. godine nije potvrđena povezanost onečišćenja TBT-om s aktivnošću odabranih biomarkera (katalaza, glutation S- transferaza, glutation reduktaza, malondialdehidi, karbonili, acetilkolinesteraza), iako je uočena povećana aktivnost glutation reduktaze i glutation S-transferaze kod volaka s jače onečišćenih postaja. Istraživanje učinkovitosti zabrane korištenja TBT-a, koja je u Republici Hrvatskoj na snazi od 2006. godine, provedeno je 2015. godine na istim postajama na kojima je istraživanje imposeksa provedeno i 2005. godine, kategoriziranim prema razini brodske aktivnosti (nautičke marine, lučice, uvale koje se koriste samo sezonski, referentne postaje koje se rijetko koriste). Rezultati istraživanja sugeriraju da je u desetogodišnjem razdoblju došlo do smanjenja razine onečišćenja TBT-om. Ipak, smanjenje nije rezultiralo oporavkom istraživanih populacija budući da je kod svih utvrđen visoki udio imposeksa kao i povećanje udjela sterilnih ženki. U svrhu potencijalnog korištenja vrste H. trunculus kao bioindikatora u ocjeni ekološkog stanja priobalnih voda u okviru Direktive o vodama, a s obzirom na onečišćenje voda TBT-om i posljedičnim razvojem imposeksa, predložene su granične vrijednosti omjera ekološke kakvoće (OEK) . Istraživanjem stabilnih izotopa dušika (Ł15Nair) i ugljika (Ł13CVPDV) u tkivu volka H. trunculus nije potvrđena povezanost sadržaja stabilnih izotopa sa stupnjem onečišćenosti istraživanih postaja TBT-om.Banded murex Hexaplex trunculus is used in the marine environment monitoring of organotin pollution, as this species develops imposex at very low tribytiltin (TBT) concentration. In this thesis relationship between imposex in H. trunculus and TBT pollution was investigated along the central Croatian Adriatic coast at 7 sites in 2014 and 12 sites in 2015. Imposex was recorded at all investigated sites on which also TBT pollution was demonstrated, both in tissue of H. trunculus and in sediment. Investigations performed in year 2014 showed no connection between degree of TBT pollution and activity of specific biomarkers (catalase, glutathione S-transferase, glutathione reductase, malondialdehydes, carbonyls, acetylcholinesterase) in gastropod, although the increased activity of glutathione reductase and glutathione S-transferase in banded murex from the most polluted sites was observed. Investigation on effectiveness of the ban of organotin compounds in antifouling coatings, which is in force in the Republic of Croatia since 2006, was performed in 2015 at the same sites previously investigated in 2005 which were categorized according to intensity of boating activities to nautical marinas, village harbours, sheltered bays and reference sites. Obtained results suggested that TBT pollution has decreased in this ten years period. However, this decrease was not sufficient for the recovery of H. trunculus populations, since in 2015 all populations showed high degree of imposex and even higher number of sterile females than in 2005. The Ecological Quality Ratio (EQR) values for the potential use of imposex in H. trunculus as bioindicator in assessment of the ecological status of coastal waters regarding TBT pollution in the frame of Water Framework Directive (WFD) are proposed. Relationship between carbon (Ł13CVPDV) and nitrogen (Ł15Nair) isotopes content in H. trunculus and degree of TBT pollution was not established
Selectivity of Norway lobster Nephrops norvegicus (Linnaeus, 1758) in demersal trawls
No full textZa potrebe ovog rada uzorkovano je 100 primjeraka škampa (Nephrops norvegicus) duljine karapaksa od 19 do 47 mm. Testom propadanja svaki škamp se pokušao na različite načine provući kroz niz oka točno definirane veličine i kuta između susjednih stranica, kako bi se utvrdilo na koje sve načine škamp može pobjeći iz vreće pridnene povlačne mreže koće. Od ukupno tri testirana načina bijega, dva su se pokazala realnima. Za oba realna načina bijega kreiran je model za predikciju selektivnosti škampa u vreći koće. Oba modela su potvrđena eksperimentalnim podacima o selektivnosti škampa dobivenima iz znanstvene literature. Dobiveni modeli omogućuju predikciju selektivnosti škampa u vrećama pridnene povlačne mreže koće izrađene od romboidnog mrežnog tega različite veličine i kutova između susjednih stranica.For the purposes of this thesis, 100 individuals of Norway lobster (Nephrops norvegicus) were sampled, with carapace length ranging from 19 to 47 mm. They were tested for their ability to pass through the range of meshes with precisely defined sizes and opening angles in three different ways. Two escapement modes in which Norway lobster can pass through the meshes of demersal trawl codend were identified as realistic: “curled tail first” and “extended tail first”. A model that predicts Norway lobster selectivity in diamond mesh codends was created for each escapement mode. Both modes were validated with the experimental size selectivity data obtained from the scientific literature. This allows predicting the size selectivity of Norway lobsters in a diamond mesh codends for wide variety of mesh sizes and mesh opening angles
Age and growth of bogue, Boops boops (L.) in central eastern Adriatic Sea
No full textCilj ovog istraživanja je prikazati osnovne značajke starosti i rasta bukve, Boops boops (L.) u srednjem istočnom Jadranu. Analizirane jedinke ulovljene su u razdoblju od rujna 2015. do svibnja 2016. godine. Ukupna dužina tijela jedinki bila je u rasponu od 12,0 do 23,0 cm (Xsr ± SD; 19,1 ± 1,78 cm), a masa tijela u rasponu od 27,0 g do 129,75 g (71,5 ± 18,8 g). Vrijednost eksponenta b iz dužinsko – masenog odnosa nije se statistički značajno razlikovala među spolovima te za ukupni uzorak iznosi b = 2,63, što ukazuje na negativan alometrijski rast ove vrste. Starost 191 jedinke određena je očitavanjem godišnjih prstenova prirasta na otolitima te su iste raspoređene u starosne skupine od 1 do 5 godina. Parametri starosti i rasta određeni von Bertalanffyevom jednadžbom su sljedeći: L∞ = 22,70 cm; k = 0,41 god-1; t0 = - 2,21 godina za mužjake i L∞ = 22,48 cm; k = 0,49 god-1; t0 = - 1,69 godina za ženke.The aim of this paper is to present the results of the study of age and growth of bogue, Boops boops (L.) from the central eastern Adriatic Sea. The individuals used in this study were collected from September 2015 till May 2016. Total body length of sampled specimens ranged from 12.0 to 23.0 cm (Xsr ± SD; 19.1 ± 1.78 cm) and total body weight ranged from 27.0 g to 129.75 g (71.5 ± 18.8 g). The value of exponent b from the weight – length relationship didn't show statistically significant difference between the sexes so the pooled value of b = 2.63 was calculated, indicating negative alometric growth of bogue. The age of 191 individuals was determined by otoliths rings readings, and each was accordingly allocated to age classes from 1 to 5 years. The growth and age parameters calculated using the Von Bertalanffy equation were as follows: L∞ = 22,70 cm; k = 0,41 god-1; t0 = - 2,21 years for males and L∞ = 2,48 cm; k = 0,49 god-1; t0 = - 1,69 years for females