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In the present study we reported the expression of neurofilaments (NFs) and glial fibrillary acidic protein (GFAP) and for the first time the expression of dendrin in the brain of small- spotted catshark Scyliorhinus canicula L. Small-spotted catshark is a well-known model species of cartilaginous fishes. Its developing telencephalon shows more similarities to those of mammals than to those of bony fishes, amphibians, and birds. Neurofilaments (NFs) are members of the intermediate filament protein family which are essential for the formation of the neuronal cytoskeleton. GFAP is expressed by numerous central nervous system (CNS) cell types, including astrocytes and ependymal cells during development. Dendrin, a proline-rich protein known as a neuron and renal protein, has an important role in synaptic plasticity and as a postsynaptic component has a significant impact in modulating synaptic cytoskeleton. The tissues of sectioned forebrain, midbrain, and hindbrain of ten specimens of Scyliorhinus canicula L. fresh-caught in the Adriatic Sea were studied using histochemical and immunofluorescence techniques. Hematoxylin-eosin and Mallory staining were used to identify the histological structure of these brain parts. These sections were observed using a Leica DM 3000 LED microscope (Leica Microsystems, Germany). For immunofluorescence, the sections were incubated overnight with primary antibodies according to their own protocols followed by incubation with suitable secondary antibodies for one hour. The nuclei were stained with DAPI. The images were captured with epifluorescence microscope Olympus BX51 (Olympus Corporation, Tokyo, Japan). The present study has shown that morphological and histochemical composition of the forebrain and midbrain have many similarities. Most of the neuronal tissue are neuronal and glial cells bodies surrounded by neuropil. In the cerebellum, three layers could be distinguished: the most superficial layer, the middle one called the Purkinje cells layer and the deepest granular one. The other part of the hindbrain, the medulla oblongata, histologically resembles the granular cerebellum layer. NF, GFAP, and dendrin in the catshark's brain are highly expressed in all parts of the brain except in the medulla oblongata where the expression pattern was weaker for all investigated proteins. Morphological and histochemical analysis of the small-spotted catshark’s brain confirmed the great potential of this cartilaginous fish not only as a model for evo- devo studies but as a model in the adult stage that shows more similarities to mammals than it was thought, with the special emphasis on the distribution of dendrin in the non-mammalian brain for the first time.

INTRODUCTION The enzyme myrosinase catalyses the hydrolysis of a group of low molecular weight compounds, the glucosinolates [1, 2]. This two-compound system of secondary products and degradative enzymes is momentous in plant-insect interactions [3]. Tissue disruption brings glucosinolates into contact with myrosinases, resulting in the release of various components with diverse biological activities (anticancer, antbacterial, antifungal…[4, 5]. The myrosinase refers to a certain type of idioblasts called myrosin cells [2]. Myrosin cells are present in several tissues in the plant including the cotyledons and axis of the embryo as well as in the leaves, the stem, the root, the petals, and the siliques of the adult plant [1]. Nasturtium (Tropaeolum majus L.) is a plant that belongs to the Tropaeolaceae family (order Brassicales) and is known for its ornamental and medicinal properties [6].The aim of this study was to investigate the expression of the enzyme myrosinase type 1 in the nasturtium leaf, stem and root regions in the different developmental stages after plant's sprout. MATERIALS AND METHODS Nasturtium tissues were cut into small pieces at different developmental stages after sprouting. The specimens were fixed in 4% paraformaldehyde in phosphate buffer pH 6.8, dehydrated in an ascending series of ethanol, cleared in xylene, and then embedded in paraffin wax. Paraffin sections cut on a rotary microtome were mounted on glass slides [7]. After deparaffinization and rehydration, sections were heated in a citrate buffer (pH 6.0), cooled and a blocking buffer was applied to exclude unspecific staining. Sections were then incubated overnight at RT with TGG1 myrosinase 1 (BGL38) rabbit primary antibody, diluted 1/1000 in PBS. After washing in PBS, Alexa Fluor 488 anti-rabbit IgG secondary antibody, diluted 1/400 in PBS was applied for 1 h and washed in PBS again. Then, nuclei were stained with DAPI. All slides were studied using an Olympus BX51 epifluorescence microscope with digital camera a Nikon DS-Ri1 (Japan). RESULTS The enzyme myrosinase has been found in all investigated organs of the T. majus plant, in idioblasts, also called myrosin cells. The idioblasts are specialized cells that are scattered at low frequency and often as single cells among the other major cells in a tissue. Myrosin cells are anatomically characterized by a high protein content in the vacuole and thus are prone to react cytochemically with certain protein reagents. Immunofluorescence positive myrosinase type 1 enzyme appeared in ground tissue and the vascular tissue in all investigated parts of the plant. In the root, the strongest positive expression of the myrosinase was found in the ground tissue idioblasts in phase 1 and phase 2 of the developmental period. Also, the parenchyma xylem and phloem cells of the root region have shown positive immunoexpression. In the stem, large xylem vessels with empty lumens and tick cell walls in phases 2 and 3 show a distinguished location of the myrosinase, as well as the phloem cells. No significant immunoexpression of the enzyme myrosinase type 1 was observed in all four different developmental phases in the leaf region. Nevertheless the xylem (with pronounced annular thickening) parenchyma cells and through the ground tissue weak signal of enzyme myrosinase type 1 in the leaf region of the nasturtium was observed. CONCLUSION Myrosin cells are specialized cells that are scattered at low frequency associated with the enzyme myrosinase. Myrosinase type 1 enzyme has been found in all investigated organs of T. majus plant. The strongest positive expression of the myrosinase was found in the ground tissue idioblasts of the root. The presence of the glucosinolate-myrosinase system is characteristic of the Brassicales order, and it serves as a defense system against biotic and abiotic stressors. REFERENCES [1] A. S. Höglund, M. Lenman, L. Rask, Plant Sci. 1992, 85, 165. [2] Y. Niu, A. Rogiewicz, C. Wan, M. Guo, F. Huang, A. Bogdan, B. A. Slominski, J. Agric. Food Chem. 2015, 63, 3078. [3] E. Andreasson, L. B. Jørgensen, A.-S. Hoglund, L. Rask, J. Meijer, Plant Phys. 2001, 127, 1750. [4] S. Chen, E. Andreasson, Plant Physiol. Biochem. 2001, 39, 743. [5] I. Vrca, F. Burčul, I. Blažević, T. Bilušić, Croat. J. Food Sci. Tech. 2021, 13, 160. [6] G. A. Garzon, R. E. Wrolstad, Food Chem. 2009, 114, 44. [7] I. Restović, K. Vukojević, A. Paladin, M. Saraga-Babić, I. Bočina, Anat. Rec. 2015, 298, 1700.

Introduction: Epidermis is a surface organ which protects animal from the environmental effects and from the pathogens. In vertebrate family, the epidermis of terrestrial animals is keratinized while in aquatic forms and amphibians can produce mucus. Amphioxus, a cephalochordate, is an important animal model in the study of vertebrate (chordate) phylogeny. Objectives: Epidermal cells of amphioxus (Branchiostoma lanceolatum L.) were investigated morphologically by transmission electron microscopy (TEM) and using immunohistochemistry and immunofluorescence for detection of a major cytoskeletal and extracellular matrix proteins. Materials & methods: The study was done on ten adult amphioxus specimens fresh-caught in the Adriatic Sea. After fixation, dehydration and embedding in paraffin blocks, paraffin sections of 6 μm thick were mounted on glass slides. For immunohistochemistry and immunofluorescence, slides were deparaffinized and rehydrated, then heated in a citrate buffer. Protein blocking buffer was used to exclude unspecific staining. The sections were incubated with primary antibodies according to their own protocols. For immunohistochemistry, DAB staining was used, and for immunofluorescence the sections were incubated with suitable secondary antibodies for one hour. For transmission electron microscopy, small pieces of tissue were fixed in 3.5% paraformaldehyde during 24 hours on 4 °C, and afterwards in 3% glutaraldehyde for 2 hours. The post fixation was done in 2% osmium tetroxide and tissue was embedded in Epoxy resin and cut transversally. Ultrathin sections, stained with uranyl acetate and lead citrate, were observed under Zeiss EM 10A electron microscope. Results: Epidermis of the amphioxus consisted of one-layered columnar epithelium. These epithelial cells were characterized by voluminous nucleus, a well-developed supranuclear Golgi apparatus, abundant vesicles and apical secretory vesicles surrounded by cytokeratin filaments. A single row of smaller vesicles also appeared close to the basal cell membrane. Short microvilli were seen on the apical domain of the epidermal cells. The plasma membrane of adjacent cells strongly intertwined on its lateral domains in the form of finger-like protrusions. Positive immunolocalization of hyaluronic acid and collagen type I was observed in apical domain of plasma membrane of amphioxus, respectively. This positive signal probably refers to the secretory granules in the apical domain of the epidermal cell shown on the TEM. Immunolocalization of aggrecan was seen around the cell nucleus, deep below the apical domain, suggesting that aggrecan is not located in secretory granules. A strong signal to cytokeratin 10 was present throughout the cytoplasm of the epidermal cells. Conclusion: Due to its morphology and histochemical composition, epidermal cells of amphioxus may contribute to course surface protection and the mucous layer in amphioxus may serve as a physical barrier between the body and its environment.

The digestive system of Lepidorhombus whiffiagonis was studied using histological and histochemical techniques. The wall of oesophagus and stomach fundus consisted of four histological layers: mucosa, submucosa, muscularis and the outer layer. Mucosa, the innermost layer, usually consisted of three different layers, including epithelium, lamina propria and lamina muscularis mucosae. Submucosa of connective tissue with blood vessels and nerve fibres underlined the mucosa and usually protrudes into the mucosal folds except in the gallbladder where it is completely absent. The muscular layer of the digestive system consisted of smooth muscles arranged in longitudinal, circular or oblique layers. Striated fibres were found in the oesophageal wall. The outermost layer comes as tunica adventitia in upper parts and tunica serosa in lower parts of the digestive system. Hepatocytes were surrounded by a mass of fat- storing cells. Serous acini of pancreas were scattered down the length of the stomach. Alcian blue/PAS technique revealed that alkaline and neutral mucopolysaccharides were present in oesophagus while acidic mucopolysaccharides was found in the stomach and intestines.

Brown (Brassica juncea L.) mustard and Tropaeolum majus L. belong to Brassicaceae family known for the presence of glucosinolates (GSLs), secondary plant metabolites. In the plant, they coexist with an enzyme myrosinase, though separately stored in vacuoles of so-called S-cells [1]. It was originally believed that the glucosinolate–myrosinase system in intact plants was stable due to a spatial separation of the components. This has been coined as the ‘mustard oil bomb’ theory. [2] GSLs and enzyme myrosinase come into contact when the plant tissue is damaged, releasing unstable aglycones which spontaneously rearrange into a variety of reactive compounds like thiocyanates, epithiontiriles, nitriles, oxazolidines and most important – isothiocyanates [1, 2]. GSL that is characteristic for Brassica juncea L. is sinigrin and for Tropaeolum majus L. is glucotropaeolin. Sinigrin degrades and releases allyl isothiocyanate, while glucotropaeolin releases benzyl isothiocyanate [3, 4]. Some glucosinolate hydrolysis products act as a plant defence compounds against insects and pathogens or have beneficial health effects on humans [2]. The aim of this research was ultrastructure analysis of plant tissue leaves of Brassica juncea L. and Tropaeolum majus L. and try to locate the components of the glucosinolate-myrosinase system because it is different between plant organs and changes during a plant’s growth cycle.

Vitamin D is a secosteroid with multiple actions throughout the body, usually obtained from diet, dietary supplements and exposure to sun lights. Its actions are mediated via its nuclear receptor, the vitamin D receptor (VDR). There are hard evidences that correlate vitamin D deficiency with liver lipid metabolism disturbances, but the mechanism of this action is still unknown. In our previous work, we localized the accumulation of VDR in membrane of the lipid droplets (LDs) in hepatocytes. In this study, we applied the transmission electron microscopy (TEM) by using a long-term (6 months) high sucrose intake rat model for research of the hepatic lipid accumulation. In addition to the VDR, vitamin D metabolizing enzymes 1α-hydroxylase and CYP 24 were found to be associated with the membrane of the LDs. A light-microscopy data revealed significant increase in expression of VDR and CYP 24 in liver of high-sucrose treated rats in comparison to controls. These results provide a new insight in the possible relation of vitamin D signalling system with LD morphology and function and with the lipid metabolism in general.

Bryozoans are aquatic invertebrates that form large colonies by asexual budding. Each individual within a colony works as a separate zooid and is genetically identical to each other individual within the same colony. Most freshwater species of bryozoans belong to the Phylactolaemata class, while several species that tolerate brackish water belong to the Gymnolaemata class. Bryozoan samples were collected in the rivers of Adriatic and Danube basin and in the wetland areas in the continental part of Croatia. Freshwater and brackish taxons of bryozoans were genetically analyzed for the purpose of creating phylogenetic relationships between freshwater and brackish taxons of the Phylactolaemata and Gymnolaemata classes and determining the role of brackish species in colonizing freshwater and marine ecosystems. Phylogenetic relationships inferred on the genes for 18S rRNA, 28S rRNA, COI and ITS2 region confirmed Phylactolaemata bryozoans as radix bryozoan group. Comparative analysis of existing knowledge about the phylogeny of bryozoans and the expansion of known evolutionary hypotheses is proposed with the model of settlement of marine and freshwater ecosystems by the bryozoans group during their evolutionary past. Brackish bryozoan taxons represent a link for ecological‐phylogenetic hypothesis. Comparison of brackish bryozoan species Lophopus crystallinus and Conopeum seurati confirmed a dual colonization of freshwater ecosystems throughout the evolution of this group of animals.

Process of endosymbiosis is one of promoters of speciation. The green hydra (Hydra viridissima Pallas, 1766) is a typical example of endosymbiosis. Its gastrodermal myoepithelial cells harbor the individuals of unicellular photoautotrophic algae. We have established prosperous laboratory cultures of endosymbiotic green algae isolated from green hydra strains. Hydra strains were from 6 different geographical localities: 4 from Croatia, 1 from Israel and 1 from Germany. Endosymbiotic green algae were successfully isolated using microbiological methods. Isolated endosymbiotic algae were characterized employing cytological morphometric parameters, enzyme activity and isoenzyme pattern analysis (catalase, peroxidase and esterases). Cells of endosymbiotic algae were characterized by morphometric measurements: diameter, perimeter and area. Algal HV and M9 strains were separated from strains T and BV. The results obtained by isoenzyme pattern analysis suggest a difference between Croatian and European algal endosymbionts, indicating biological diversity among algal symbionts isolated from green hydras. Five isoenzymes of catalase and five isoenzymes of peroxidase were resolved by PAGE electrophoresis. Isoenzyme K1 appeared only in endosymbiotic algae M9 from Israel and isoenzyme K3 only in T strain. Isoenzyme P1 was observed only in endosymbiont HV while isoenzyme P5 in both endosymbionts HV and M9. Isoenzymes P3 and P4 were visible only in algal strains BV and T from Croatia.

Tanko crijevo, kao jedan od najosjetljivijih organa u našem tijelu, predstavlja prvu crtu obrane unutar našeg organizma. S obzirom da je u izravnom kontaktu s različitim sastojcima koje unosimo u naš organizam, može burno reagirati, to jest aktivirati imunološki odgovor na pojedine komponente hrane. Jedna od takvih komponenata je gluten, koji u velikom broju slučajeva oštećuje sluznicu tankoga crijeva, inhibirajući enzim tkivnu transglutaminazu. Neka od stanja koja se mogu javiti kao reakcija na gluten su: malapsorpcijski sindrom, netolerancija na gluten ili alergija, necelijakična osljetljivost na gluten, celijakija ili glutenska enteropatija, glutenska ataksija i herpetiformni dermatitis., The small intestine, as one of the most sensitive organs in our body, represents the first line of defense within our organism. Given that it is in direct contact with various ingredients that we introduce into our body, it can react violently and activate an immune response to individual food components. One of such components is gluten, which in many cases damages the mucosa of the small intestine, inhibiting the enzyme tissue transglutaminase. Some of the conditions that can occur as a reaction to gluten are: malabsorption syndrome, gluten intolerance or allergy, non-celiac gluten sensitivity,celiac disease or gluten enteropathy, gluten ataxia and dermatitis herpetiformis.

U ovom radu istražena je ekspresija proteina intermedijarnih filamenata (NF, GFAP, CK8 i CK10) te dendrina u mozgu morske mačke (Scyliorhinus canicula). Kao osnovni materijal korišten je mozak morske mačke, podijeljen na dijelove: prednji, srednji i stražnji mozak. Korištenjem histoloških i histokemijskih tehnika bojanja (HE i Mallory bojanje) određena je histološka građa ovih dijelova mozga. Tehnikom imunofluorescencije određena je ekspresija navedenih proteina u mozgu morske mačke. Ekspresija NF-a, GFAP-a i dendrina u mozgu morske mačke je jaka za razliku od ekspresije citokeratina koja je slabija., In this paper, the results of research on the expression of intermediate filament proteins (NF, GFAP, CK8, and CK10) and dendrin in the brain of the small-spotted catshark (Scyliorhinus canicula) are presented. As a basic material, the catshark's brain was used, divided into parts: forebrain, midbrain, and hindbrain. The histological structure of these parts of the brain was identified by using histological and histochemical staining techniques (HE and Mallory staining). The immunofluorescence technique was used to determine the expression of these proteins in the brain of the catshark. The expression of NF, GFAP, and dendrin in the catshark's brain is strong in contrast to the expression of cytokeratins which is weak.

U ovom radu proučavana je ekspresija proteina intermedijarnih filamenata (NF, GFAP, CK8 i CK10) i dendrina u mozgu arbuna rumenca Pagellus erythrinus. Primjenom osnovnih histoloških te histokemijskih tehnika bojenja (HE i Mallory bojenje) identificirani su dijelovi i građa velikog mozga, međumozga, srednjeg mozga i stražnjeg mozga. Tehnikom imunofluorescencije detektiran je slab izražaj proteina specifičnih za živčano tkivo (NF, GFAP i dendrin) kao i CK8 i CK10, specifičnih za epitelno tkivo., Objective of this thesis has been to research the expression of intermediate filaments (NF, GFAP, CK8 and CK10) as well as dendrin in the brain of the common pandora Pagellus erythrinus. The research was conducted by basic histological and histochemical techniques (HE and Mallory staining) which led to identification and structure of forebrain, interbrain, midbrain and hindbrain. It has been observed overall low immunoreactivity expression of neural proteins (NF, GFAP and dendrin) as well as epithelial proteins (CK8 and CK10) in an indirect immunofluorescence assay.

Koštani sustav građen je od kostiju, hrskavice, ligamenata i tetiva. Ključne funkcije za koje je zadužen koštani sustav su potpora i pokretanje tijela zajedno s mišićima, zaštita unutarnjih organa, skladištenje minerala te hematopoeza. Bolesti koštanog sustava su česte u populaciji, a njihovi uzročnici su raznoliki (dob, prehrana, genetika, hormoni itd.). U ovom radu obrađene su neke od bolesti koštanog sustava, kao što su koštani tumori i metaboličke bolesti kostiju. Tri su spomenute vrste koštanih tumora, a to su: osteosarkom, osteoblastom i osteoklastom. Uslijed poremećaja ravnoteže određenih minerala u kostima, prvenstveno kalcija, dolazi do razvoja različitih metaboličkih bolesti kostiju od kojih su obrađene sljedeće: osteopenija i osteoporoza, osteomalacija, rahitis i Pagetova bolest kosti., Skeletal system is built of bones, cartilage, ligaments and tendons. The key functions that the skeletal system is responsible for are the support and movement of the body together with the muscles, protection of internal organs, storage of minerals and hematopoiesis. Diseases of the skeletal system are common in the population, with various causes (age, diet, genetics, hormones, etc.). Furthermore, this paper examines some of the diseases of the skeletal system, such as bone tumors and metabolic bone diseases. There are three types of bone tumors mentioned, and those are: osteosarcoma, osteoblastoma and osteoclastoma. Disorders of the balance of certain minerals in the bones, primarily calcium, lead to the development of various metabolic bone diseases, of which the following have been described: osteopenia and osteoporosis, osteomalacia, rickets and Paget's disease of bone.

Nagli razvoj tehnologije omogućio je napredak imunologije i nastanak imunoterapije kao novog pristupa liječenju mnogih poremećaja i bolesti. Regresija zloćudnih tumora te usporavanje napretka progresivnih, autoimunosnih bolesti mnogim su osobama dali novu šansu za život. Ublažavanje i utišavanje alergijskih reakcija povećalo je kvalitetu života. Moderna imunosupresijska terapija znatno je poboljšala presađivanje i produžila životni vijek bolesnika. Neizmjeran potencijal imunoterapije leži u širokom spektru njezina djelovanja te specifičnosti koja pruža individualan pristup svakome pojedincu. Iako relativno nova disciplina, imunoterapija se razvija strahovitom brzinom obećavajući još mnogo toga u budućnosti.

Dojenje je jedan od najvažnijih načina za osiguranje zdravlja i razvoja djeteta. Majčino mlijeko djeluje kao “prvo cjepivo”, jer je sigurno, čisto i sadrži protutijela koja pomažu u zaštiti od mnogih dječjih bolesti. Novorođenče u prvim danima treba dojiti što češće. Rani početak izdajanja mlijeka potaknut će proizvodnju mlijeka u dojkama te pospješiti laktogenezu. U prvom satu života, dojenje smanjuje visoku smrtnost novorođenčadi s dodatnim zaštitnim učinkom koje pruža prvo mlijeko, kolostrum. Djeca koja doje imaju bolji uspjeh na testovima inteligencije i manje su sklona razvitku prekomjerne tjelesne težine i dijabetesa u kasnijoj životnoj dobi, dok dojilje imaju smanjen rizik od nastanka raka dojke i jajnika. Učestalost dojenja je još uvijek niska te je potrebno uložiti napor da se produži vrijeme koje dijete provede dojeći., Breastfeeding is one of the most important ways to ensure the health and development of a child. Breast milk acts as the “first vaccine” because it is safe, pure and contains antibodies that help protect against many childhood diseases. The newborn should be breastfed as often as possible in the first days. Early onset of milk production will stimulate breast milk production and enhance lactogenesis. In the first hour of life, breastfeeding reduces the high infant mortality rate with additional protective effects provided by the first milk, colostrum. Children that breastfeed have better results on intelligence tests and are less prone to developing overweight and diabetes in later life, while breastfeeding women have a reduced risk of developing breast and ovarian cancer. The frequency of breastfeeding is still low and it is necessary to make an effort to prolong the time the baby spends breastfeeding.

Leukemije su maligne bolesti karakterizirane neoplastičnom proliferacijom jedne ili više loza stanica u koštanoj srži. Simptomi bolesti uglavnom uključuju povišenu temperaturu, krvarenja, povećanje slezene, jetre i limfnih čvorova. Dijagnoza se vrši analizom krvi te punkcijom koštane srži. Leukemije mogu biti akutne ili kronične, a mogu se podijeliti i na limfocitne te mijeloične. Liječenje ovisi o tipu leukemije, a obuhvaća kemoterapiju, radioterapiju i novije metode liječenja kao što je ciljana imunoterapija. Ukoliko oboljeli pacijent ne odgovara na spomenute terapije liječenja, preporuča se transplantacija koštane srži utemeljena na HLA tipizaciji (podudarnost HLA antigena primatelja i davatelja)., Leukemias are malignant diseases characterized by neoplastic proliferation of one or more cell lineages in the bone marrow. Symptoms of the disease mainly include fever, bleeding, enlargement of the spleen, liver and lymph nodes. The diagnosis is based on blood analysis and bone marrow puncture. Leukemias can be acute or chronic, and can be divided into lymphocytic and myeloid. Treatment depends on the type of leukemia, and includes chemotherapy, radiotherapy, and newer treatment methods such as targeted immunotherapy. If the affected patient does not respond to the mentioned methods, bone marrow transplantation based on HLA typing (matching of HLA antigen recipient and donor) is recommended.

Cilj ovog diplomskog rada bio je istražiti kvalitativnu ekspresiju kolagena tipa I i tipa II, agrekana, hijaluronske kiseline i citokeratina 10 u probavnom sustavu pauka bijelca Trachinus draco L. Za identifikaciju građe i dijelova probavnog sustava pauka bijelca korištene su histokemijske metode bojenja: hematoksilin-eozin, Mallory i Alcian blue-PAS, a metodom neizravne imunofluorescencije istražena je ekspresija proteina u jednjaku, želudcu i crijevu. Detektirani su signali različitih intenziteta za kolagen tipa I i II, agrekan i hijaluronsku kiselinu, dok za citokeratin 10 nisu uočeni signali ni u jednom istraživanom dijelu probavnog sustava., The aim of this thesis was to research the qualitative expression of collagen type I and II, aggrecan, hyaluronic acid and cytokeratine 10 in the digestive system of the greater weever Trachinus draco L. Histochemical staining methods hematoxylin-eosin, Mallory and Alcian blue-Pas were used to identify the structure and parts of the digestive system, while indirect immunofluorescence was used to research protein expression in the esophagus, stomach and intestines. Signals of different intensities were detected for collagen type I and II, aggrecan and hyaluronic acid, while for cytokeratin 10 no signals were observed in any of the investigated parts of the digestive system.

Genska terapija već je dugi niz godina okrenuta borbi protiv raka i osmišljavanju novih načina i pristupa liječenja. Temelji se na unosu gena ili genskih segmenata s ciljem modifikacije stanica raka. Napredak je ostvaren razvojem virusnih i nevirusnih vektora kao nosača gena, te raznim mehanizmima djelovanja genske terapije poput utišavanja onkogena, zamjena tumor supresorskih gena, popravak gena i imunoterapija. Jedna od prednosti genske terapije je upravo selektivno ciljanje i eliminacija tumorskih stanica čime se postiže jako mala toksičnost za okolna tkiva i organe. Još uvijek su prisutni problemi po pitanju konstrukcije idealnog vektora koji bi omogućio popravak genskih mutacija i imao najmanju moguću toksičnost za pacijenta. Trenutno aktualna nanotehnologija ima bitnu ulogu u konstrukciji novih i efikasnih nevirusnih vektora u genskoj terapiji. Postoji velik broj kliničkih ispitivanja sa tek nešto uspješnim rezultatima te malim brojem odobrenih i dostupnih terapija. Aktiviranje imunološkog odgovora protiv tumorskog tkiva (imunoterapija) jedna je od tehnika koja pokazuje obećavajuće rezultate. Iako ima brojne prednosti, mogućnosti genske terapije ograničene su zbog toksičnosti, efikasnosti i dostupnosti za komercijalnu upotrebu., For many years gene therapy has been focused on fighting cancer and devising new ways and approaches for treatment. It is based on gene or gene segments transfer with the aim of modifying cancer cells. Progress has been made by development of viral and non-viral vectors as gene carriers, and various mechanisms of action such as oncogene silencing, replacement of tumor suppressor genes, gene repair and immunotherapy. One of the advantages of gene therapy is selective targeting and elimination of tumor cells, thus achieving very little toxicity to the surrounding tissues and organs. There are still problems with the construction of an ideal vector that would allow repair of gene mutations and have the least possible toxicity for the patient. Currently, nanotechnology plays an important role in the construction of new and effective non-viral vectors in gene therapy. There are large number of clinical trials with only few successful results and a small number of approved and available therapies. Activating the immune response against tumor tissue (immunotherapy) is one of the methods with promising results. Although it has numerous advantages, the possibilities of gene therapy are limited due to toxicity, efficiency and availability for commercial use.

Hipofiza je endokrina žlijezda koja je važna za regulaciju štitne i nadbubrežne žlijezde te spolnih žlijezda (jajnici i testisi). Hipofizni poremećaji mogu uzrokovati veliki raspon različitih simptoma. Uzročnici tih simptoma su intrakranijske tvorbe te pretjerano ili nedostatno izlučivanje hormona hipofize. U ovom radu obrađene su bolesti hipofize: sindrom praznog turskog sela, tumori hipofize i hipofizitis. Hormoni hipofize su važni za regulaciju većine glavnih tjelesnih procesa, pa hormonska neravnoteža može utjecati na široki raspon tjelesnih funkcija. Neki od poremećaja uzrokovanih nedovoljnom sekrecijom hipofiznih hormona su centralna adrenalna insuficijencija, hipotireoza, hipogonadotropni hipogonadizam te dijabetes insipidus. Akromegalija, gigantizam i Cushingova bolest, za razliku od prethodno navedenih poremećaja, uzrokovani su pretjeranim izlučivanje hipofiznih hormona., The pituitary gland is gland of endocrine system that is important for the regulation of the thyroid, adrenal glands and gonads (ovaries and testicles). Pituitary disorders can cause a wide range of different symptoms. The causes of these symptoms are intracranial formations and hypersecretion or hyposecretion of pituitary hormones. Furthermore, this paper examines the pituitary diseases: the Empty Sella Syndrome, pituitary tumors and hypophisitis. Pituitary hormones are important for the regulation of most major body processes, so hormonal imbalances can affect a wide range of body functions. Hyposecretion of pituitary hormones causes diseases such as central adrenal insufficiency, hypothyroidism, hypogonadotropic hypogonadism and diabetes insipidus. Acromegaly, gigantism and Cushing's disease, in contrast to the aforementioned disorders, are caused by hypersecretion of pituitary hormones.

Stanično signaliziranje omogućuje komunikaciju između stanica. Informacije se prenose u obliku signala povezujući sve dijelove složenih organizama u funkcionalnu cjelinu. Signaliziranje omogućuje stanicama da odrede svoj položaj i funkciju u tijelu. Signalne molekule vežu se za receptore na površini stanice te pokreću niz unutarstaničnih promjena, koje nadziru sve aspekte staničnoga ponašanja, od nastanka stanice do programirane stanične smrti (apoptoze). Narušavanje prijenosa signala između stanica onemogućit će njihovu skladnu aktivnost, a to će rezultirati pojavom bolesti. Proučavanje mehanizama kojim zdrave stanice prenose signale temelj je za razumijevanje promjena u signaliziranju koje se javljaju tijekom nastanka bolesti. Zbog toga, poznavanje mehanizama prijenosa signala pomaže u pronalaženju učinkovite terapije i novih lijekova. Zanimanje za stanično signaliziranje vezano je i uz činjenicu da su brojne vrste raka posljedica prekidanja signalnih puteva koji nadziru normalnu staničnu proliferaciju i preživljenje., Cell signaling allows communication between cells. Information is transmitted in the form of signals by connecting all parts of complex organisms into a functional whole. Signaling allows cells to determine their position and function in the body. Signal molecules bind to receptors on the cell surface and trigger a series of intracellular changes, which control all aspects of cellular behavior, from cell formation to programmed cell death (apoptosis). Disruption of signal transmission between cells will prevent their harmonious activity, and this will result in the appearance of disease. The study of the mechanisms by which healthy cells transmit signals is the basis for understanding the changes in signaling that occur during disease onset. Therefore, knowledge of signal transduction mechanisms helps in finding effective therapies and new medications. Interest in cellular signaling is also related to the fact that many cancers are the result of disruption of signaling pathways that monitor normal cell proliferation and survival.

Sindrom policističnih jajnika je najčešći endokrinološki poremećaj u žena reproduktivne dobi, koji se javlja u 6,5% do 25% žena ovisno o dijagnostičkim kriterijima. Uključuje niz znakova i simptoma koji karakteriziraju poremećaj pri kojemu za postavljanje dijagnoze ne postoji jedinstveni dijagnostički test. Zbog nedostatka jasnog uzroka i mehanizma nastanka, definira se na osnovu dogovorenih kriterija. Unatoč nedostatku jasnog uzroka, smatra se složenom genskom bolesti koja u interakciji s okolišnim čimbenicima rezultira različitim fenotipskim varijantama. Glavna obilježja sindroma policističnih jajnika su povećano stvaranje androgena, poremećaj ovulacije i policistični izgled jajnika. Povezuje se s brojnim metaboličkim poremećajima kao što su inzulinska rezistencija, hiperinzulinemija, dijabetes tip 2, dislipidemija, hipertenzija, bolesti kardiovaskularnog sustava te pretilost. Povezan je i s reproduktivnim poremećajima poput abnormalnih krvarenja maternice, nenormalnosti endometrija i neplodnosti. Jako je bitno identificirati, redovito pratiti značajke i liječiti sindrom policističnih jajnika da bi se smanjio rizik od razvoja komplikacija.

Genomski utisak je epigenetski fenomen u kojem aktivnost gena ovisi o roditeljskom podrijetlu. Za razliku od Mendelovog nasljeđivanja gdje oba alela jednako doprinose fenotipu jedinke, utisnuti gen eksprimiran je samo s jednog roditeljskog alela, dok je alel naslijeđen od drugog roditelja utišan (inaktivan). Genomski utisak svoj trag ostavlja tijekom gametogeneze i ranog embrionalnog razvoja. Ovaj rad opisuje tri najznačajnija molekularna mehanizma u pozadini genomskog utiska: metilacija DNK, modifikacije histona i nekodirajuće RNK. Tijekom ranih istraživanja u području epigenetike, otkrivena su dva rijetka genetička poremećaja koja se dovode u direktnu vezu s genomskim utiskom, Prader-Willi i Angelmanov sindrom., Genomic imprinting is an epigenetic phenomenon in which gene activity depends on parental origin. Unlike inheritance based on Mendel's laws where both alleles equally contribute to the phenotype of an individual, the imprinted gene is expressed only from one parental allele, while the allele inherited from the other parent is silenced (inactive). The genomic imprinting leaves its mark during gametogenesis and through the early embryonic development. In this thesis, we will discuss the three most important molecular mechanisms of genomic imprinting: DNA methylation, histone modification and noncoding RNA. During the first research in the field of epigenetics, two rare genetic disorders directly related to genomic imprinting were discovered, Prader-Willi and Angelman syndrome.

Krvni ugrušci ili trombi nastaju reakcijom krvnih pločica (trombocita) i unutarnjeg dijela stjenke arterija, no mogu nastati i unutar srca, vena i kapilara. Ključni su dio dvaju važnih procesa u ljudskom organizmu hemostaze i tromboze. Hemostaza je normalan fiziološki proces čiji je cilj zaustaviti krvarenje i održati organizam na životu nakon zadobivene ozljede. Odvija se na oštećenoj krvnoj žili gdje je potrebno brzo zaustaviti gubitke velike količine krvi. Uz stvaranje krvnog ugruška, drugi mehanizmi za održavanje hemostaze su stezanje krvnih žila, stvaranje trombocitnog čepa i urastanje vezivnog tkiva. Tromboza je patološki proces koji podrazumijeva stvaranje krvnih ugrušaka u neoštećenoj žili ili žili s relativno malim oštećenjem. Stvaranje ili putovanje krvnih ugrušaka mogu uzrokovati niz različitih bolesti i stanja poput ateroskleroze, srpaste anemije, tromboze femoralne vene, masivne plućne embolije., Blood clots or thrombi are formed by the reaction of platelets and the inner part of the artery wall, but they can also occur inside the heart, veins and capillaries. They are a key part of the two most important processes in the human body, hemostasis and thrombosis. Hemostasis is a normal physiological process whose goal is to stop bleeding and keep the body alive after satisfying the following. It takes place on a damaged blood vessel where it is necessary to quickly stop the loss of large amounts of blood. In addition to the formation of a blood clot, other mechanisms for maintaining hemostasis are constriction of blood vessels, formation of a platelet plug, and ingrowth of connective tissue. Thrombosis is a pathological process that involves the formation of blood clots in an undamaged vessel or a vessel with relatively little damage. The formation or travel of blood clots can cause a variety of diseases and conditions such as atherosclerosis, sickle cell anemia, femoral vein thrombosis, massive pulmonary embolism.

Virusi dišnog sustava su uzročnici najvećeg broja infekcija kod ljudi. Budući da možemo liječiti samo simptome koje virusi dišnog sustava uzrokuju, uz prevenciju najbolju obranu organizmu osigurava imunosni sustav. Cilj je ovog rada opisati viruse dišnog sustava kao uzročnike najvećeg broja infekcija i načine na koje imunosni sustav reagira na navedene infekcije., Respiratory system viruses are causative agents for the largest number of infections in humans. As there is no way to cure the disease but only symptoms of the one, our immune system is the best way of defense from these viruses beside prevention. Aim is to describe respiratory system viruses as the causative agents for the largest number of infections and the way in which immune system responds to those infections.

Koža je jedan od najvećih organa ljudskoga tijela. Čini zaštitnu granicu od okolnoga svijeta, ima brojne fiziološke funkcije i specifičnosti koje ju čine jednim od najkompleksnijih organa. Cilj ovoga rada jest opisati embriološko podrijetlo i histološku građu kože i njezinih tvorevina, istražiti utjecaj Sunčevog svjetla na metaboličke procese kože i pružiti uvid u sastav mikroflore kože., The skin is one of the biggest organs of the human body. It protects from the surrounding world and has many physiological functions and specifics, which make it one of the most complex organs. The aim is to describe the embriological origin and histological structure of the skin and its derivates, to explore the influence of Sunlight on the metabolic processes of the skin and to provide insight into the composition of the skin microflora.

U ovom radu su prikazani rezultati istraživanja histoloških i biokemijskih osobina probavnog sustava salpe. Osnovni materijal pri istraživanju bio je probavni sustav salpe raspodijeljen na: jednjak, fundus, pilorus, piloričke nastavke, crijevo, jetru i žučni mjehur. Pri izradi mikroskopskih preparata od tkiva pojedinih organa, korištene su histokemijske tehnike bojenja: Hematoksilin-eozin tehnika (HE), Alcian blue-PAS (alcijansko modrilo), Mallory metoda i Pinkusovo bojenje s kiselim orceinom i Giemsom. Istraživanjem je utvrđeno kako se stijenka većine proučavanih organa sastoji od: sluznice, podsluznice, mišićnog i vanjskog sloja. Probavni sustav salpe ima sličnosti s probavnim sustavima drugih riba koštunjača., This paper presents the results of the reaserch about histological and biochemical characteristics of the digestive system of salema porgy. Main reaserch material was salema porgy`s digestive system divided into: oesophagus, stomach, pyloric caeca, intestines, liver and gall bladder. For tissue preparation hematoxylin-eosin, Alcian blue-PAS, Mallory and acid orcein-Giemsa staining techniques were used. Results showed that the wall of most of the observed organs is made of: mucosa, submucosa, muscular and outer layer. Digestive system of salema porgy is similar to those of other teleost fish.

Priroda učenja započinje promatranjem, a to je osobito primjenjivo u znanosti jer se sva znanost definira promatranjem. Mikroskop omogućuje da se predmet promatra pod širokim vidnim kutom, kao da je maksimalno blizu oku, a da istodobno njegova slika ostane oštra i jasna. Mikroskopijske tehnike se sve više razvijaju te omogućuju ljudskom oku promatranje čestica veličine do 0,005 μm. Vrste mikroskopa su optički - koristi vidljivu svijetlost za stvaranje slike, fluorescencijski - koristi fluorescenciju za povećanje razlučivosti, elektronski - koristi elektrone umjesto svjetlosti, atomski - koristi se na atomskoj razini za izradu slika površine te rentgenski- upotrebljava x-zrake umjesto vidljive svjetlosti i koristi se za gledanje unutar malih objekata i struktura. Cilj ovog rada je upoznati se s mikroskopijskim tehnikama koje se koriste u biologiji., Nature of learning begins with observation, and it is especially applicable in science because science is defined by observation. A microscope allows the object to be viewed at a wide angle, as close as possible to eye of the viewer, while keeping image sharp and clear. Microscopic techniques have evolved throughout history to allow human eye to observe particles up to 0.005 μm in size. Types of microscopes are: optical microscopes - use of visible light to create an image, fluorescence microscopes - use of fluorescence to increase resolution, electron microscopes - use of electrons instead of light, probe testing microscopes - are used at atomic level to produce surface images and x-ray microscopes - use of x-rays instead of visible light and they are used to look inside small objects and structures. The aim of this thesis is to get familiar with microscopic techniques used in biology.

U ovom radu predstavljeni su rezultati istraživanja histokemijskih osobitosti probavnog sustava komarče. Kao osnovni materijal upotrijebljeno je probavilo komarče, razlučeno na dijelove: jezik, jednjak, želudac, pilorus, crijevo, kao i probavne žlijezde jetra i gušterača. Korištenjem histokemijskih tehnika Hemalaun-eozin, Alcian blue – PAS i Pinkusovo bojenje kiselim orceinom i Giemsom od tkiva su izrađeni mikroskopski preparati. Prilikom proučavanja mikroskopske građe organa probavnog sustava utvrđeno je da se većina sastoji od: sluznice, podsluznice, mišićnog i vanjskog sloja. Probavni sustav komarče pokazuje sličnost s građom probavnog sustava drugih riba koštunjača., In this paper, the results of a research on histochemistry of the digestive system of a gilthead seabream are presented. As a basic material digestive system of a gilthead seabream, resolved into: tongue, esophagus, stomach, pylorus, pyloric parts, intestine and digetisve glands is used. The tissues were prepared using hematoxylin and eosin staining, Alcian blue-PAS staining and acidorecin and Giemsa staining. The results have shown that digestive system of gilthead seabream consists of mucous, submucous, muscular and outher layer. The digestive system of a gilthead seabream shows similar structure of a digestive system as other teleost fish.

Intolerancija na laktozu javlja se kod osoba koje ne mogu probaviti mliječni šećer (laktozu). Razlikujemo četiri tipa intolerancije na laktozu: razvojna (neonatalna) intolerancija, kongenitalna (prirođena) intolerancija, sekundarna (stečena) intolerancija te primarna intolerancija laktoze (adultna hipolaktazija). Simptomi nepodnošenja laktoze variraju od osobe do osobe, ovisno o količini konzumirane laktoze, stupnju nedostatka enzima laktaze i namirnicama kojima se laktoza unosi u organizam. Važno je utvrditi radi li se o trajnom ili prolaznom nedostatku enzima koji je razgrađuje kako bi se primjenio adekvatan tretman za rješavanje uzroka simptoma. Ukoliko se mlijeko i mliječni proizvodi eliminiraju iz svakodnevne prehrane, potrebno je nadoknaditi kalcij i vitamin D iz drugih izvora kako ne bi došlo do neadekvatne mineralizacije kostiju., Lactose intolerance occurs in people who cannot digest lactose (lactose). We differentiate four types of lactose intolerance: developmental (neonatal) intolerance, congenital (intracranial) intolerance, secondary (acquired) intolerance and primary lactose intolerance (adult hypolactation). The symptoms of lactose intolerance vary from person to person, depending on the amount of lactose consumed, the degree of lactase enzyme deficiency and the foods that enter lactose in the body. It is important to ascertain whether there is a permanent or transient deficiency of the degenerating enzyme in order to apply an adequate treatment to resolve the symptoms. If milk and dairy products are eliminated from daily diet, it is necessary to compensate calcium and vitamin D from other sources in order to avoid inadequate bone mineralization.