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Influence of smoking during pregnancy
No full textDuhanski dim sadrži štetne tvari kao što su nikotin, ugljikov monoksid, policiklički aromatski spojevi, amonijak itd. Takvi spojevi su štetni za čovjeka koji konzumira cigarete, ali i za ljude koji su pasivni pušači. U ovom radu opisane su kancerogene tvari iz duhanskog dima te njihov utjecaj i posljedice koje uzrokuju tijelu čovjeka odnosno trudnici i fetusu. Rad je podjeljen u nekoliko poglavlja pa prvi dio čini uvod, drugi literaturni dio u kojem se opisuju djelovanja tvari, njihove strukturne formule, svojstva itd. Nadalje, opisuju se štetnost i posljedice pušenja cigareta u trudničkim danima na fetus i na novorođeno dijete. U trećem dijelu je zaključak, a zatim korištena literatura.Cigarette smoke contains harmful substances such as nicotine, carbon monoxide, polycyclic aromatic compounds, ammonia, etc. Such compounds are harmful to a man who consumes cigarettes but also to people nearby. In this paper the carcinogenic substances from tobacco and their influence and the consequences that are caused to the human body, pregnant women and fetus are described. The paper is divided into several chapters, so the first part is the introduction, the second is literary part that describes the effects of the substances, their structural formulas, properties, etc. Furthermore, it describes the harm and the consequences of cigarette smoking in pregnancy on the fetus and the newborn child. The third part is the conclusion and in addition the used literature
Sphingolipid metabolism dysfunctions
No full textSfingolipidi su glavne komponente staničnih membrana u živčanom sustavu svih eukariota. S obzirom da su uklopljeni u stanične membrane, oni kontroliraju i bitne stanične signalne puteve. Najveću ulogu u staničnoj signalizaciji ima ceramid koji inducira staničnu smrt mijenjajući pritom strukturu membrana. Ostali sfingolipidi koji su odgovorni za izgradnju dijele se na glikosfingolipide i fosfosfingolipide. Disfunkcijom metabolizma bilo kojeg sfingolipida dolazi do njihovog nakupljanja, a samim time i pojave neuroloških oboljenja. Lizosomske bolesti nakupljanja kod kojih dolazi do pogrešne razgradnje i skladištenja tih lipida nazivaju se sfingolipidoze. Sfingolipidoze su nasljedne bolesti uzrokovane nedostatkom enzima za razgradnju ili sfingolipid aktivirajućih proteina (SAP). Iako terapije za većinu tih bolesti nisu dostupne zbog neistraženosti njihove etiologije, daljnjim istraživanjima otkrivaju se nove potencionalne metode za njihovo liječenje.Sphingolipids are the main constituents of cell membranes in the nervous system of all eukaryotes. Being embedded in the cell membranes they also control some of the most important cellular signaling pathways. Ceramide plays a major role in intracellular signaling, changing the structure of cell membranes and thereby inducing the apoptosis. The remaining sphingolipids that act as building blocks are divided into glycosphingolipids and phosphosphingolipids. Dysfunctions in sphingolipid metabolism lead to their accumulation in lysosomes, acting as a trigger for neurological disorders. Lysosomal storage diseases, which arise because of the defects in degradation and storage of sphingolipids, are called sphingolipidoses. Sphingolipidoses are a group of hereditary genetic diseases caused by a lack of sphingolipid-degrading enzymes or sphingolipid activator proteins (SAP). Treatments for most of these diseases are not yet established because of the poor understanding of their ethiologies, although, novel studies are discovering potentially new methods for their treatment
Validation of the HPLC method for the determination of benzo(A)pyrene in traditional products in the Slavonia area
No full textValidacija analitičke metode je postupak kojim se potvrđuje da je metoda prikladna za namijenjenu svrhu. Ona je regulatorni zahtjev, kao i profesionalna odgovornost analitičara. Ciljevi rada su provesti validaciju HPLC metode za određivanje benzo(a)pirena u tradicionalnim proizvodima i odrediti koncentraciju istoga u uzorcima. Benzo(a)piren je najpoznatiji i najproučavaniji policiklički aromatski ugljikovodik (PAH). Dim nastao tijekom dimljenja sadrži benzo(a)piren, koji se adsorbira na površinu proizvoda. U radu su određivani sljedeći parametri validacije: selektivnost, točnost, linearnost, preciznost, granica detekcije, granica kvantifikacije i područje. Dobiveni rezultati zadovoljavaju postavljene kriterije prihvatljivosti i može se zaključiti da je metoda prikladna za namijenjenu svrhu. Također su određivane i koncentracije benzo(a)pirena u domaćim i industrijskim uzorcima.Validation of analytical method is a process of proving that the method corresponds to its intended purpose. It is a regulatory requirement as well as the professional responsibility of analyst. The objectives of the paper are to validate the HPLC method for the determination of benzo(a)pyrene in traditional products and to determine their concentration in the samples. Benzo(a)pyrene is the best known and most studied polycyclic aromatic hydrocarbon (PAH). Smoke developed by smoking contains benzo(a)pyrene which is adsorbed on the surface of the product. The following validation parameters are defined in this paper: selectivity, accuracy, linearity, precision, limit of detection, limit of quantification and area. The obtained results meet the eligibility criteria set, and it can be concluded that the method is suitable for its intended purpose. Concentrations of benzo(a)pyrene in domestic and industrial samples are also determined
Determination of vitamin E
No full textVitamini su esencijalni spojevi u ljudskom organizmu te ih je potrebno unositi hranom cijeloga života. Vitamini topivi u mastima uključuju vitamin E o kojem će ovdje biti više riječi. Vitamin E je vitamin koji ima ulogu biokatalizatora i antioksidansa u ljudskom organizmu. Vitamin E se ubraja u skupinu spojeva koji se nazivaju tokoferoli. Na tokoferole se mogu vezati različite skupine te ovisno što je vezano na molekulu tokoferola razlikuju se spojevi tokoferoli i tokotrienoli. Najpoznatiji i najrašireniji oblik skupine tokoferola je α-tokoferol. Određivanje vitamina E odnosno α-tokoferola može se izvršiti raznim metodama. Metode koje se u današnje vrijeme koriste najčešće se ubrajaju u skupinu kromatografskih metoda, gdje se posebno ističe tekućinska kromatografija visoke djelotvornosti (HPLC). Osim kromatografskih metoda, za određivanje vitamina E važan je postupak ekstrakcije, razne kolorimetrijske metode, spektrofotometrija, radioimunološko određivanje, elektroforeza te razne detekcije uzoraka pomoću UV-detekcije ili detekcije fluorescencijom. Sve metode koje služe za određivanje vitamina E u uzorcima, teže imati što više kvaliteta i biti što produktivnije u odnosu na dotada poznate metode.Vitamins are essential compounds in the human organism and it is necessary to get vitamins from food throughout the whole life. Vitamins soluble in oil include vitamin E, which we are going to talk about more. Vitamin E is a vitamin that has the role of a biocatalyzator and antioxidant in the human body. It belongs to a group called tocopherols. Different groups can be bound to tocopherols and depending on what is bound to them, tocopherols have two forms: tocopherols and tocotrienols. The best known and the most widespread form of group of tocopherols is α-tocopherol. Determination of vitamin E, i.e. α-tocopherols can be done through various methods. Methods used nowadays mostly belong to chromatography methods, particularly the high-performance liquid chromatography (HPLC). In addition to chromatography methods, the extraction process, colorimetric methods, spectrophotometric methods, electrophoresis, radioimmunoassay determination and different sample detection methods using UV-detection and fluorescence detection are important for determination of vitamin E. All methods used to the determine vitamin E in samples aim to have better quality and be more productive compared to already known methods
Validation of Analytical Method for Determination of Total Organic Carbon in Water
No full textUkupni organski ugljik je zbroj organski vezanog ugljika prisutnog u vodi, vezanog za otopljenu ili suspendiranu tvar. Mjera je otopljene i neotopljene organske tvari prisutne u pročišćenoj vodi. Jedan je od najvažnijih parametara u procjeni zagađenosti vode organskim zagađivalima. U radu je opisan niz različitih metoda za određivanje TOC-a. Cilj rada je provesti validaciju analitičke metode za određivanje ukupnog organskog ugljika u vodi. Validacija je postupak dokazivanja da je analitička metoda prikladna za točno određenu namjenu. U ovome radu provođena je djelomična validacija, odnosno određivani su samo neki parametri validacije, i to: linearnost, granica detekcije i kvantifikacije, preciznost i istinitost. Princip metode je sljedeći: uzorak vode (iz kojega je prethodno uklonjen anorganski ugljik dodatkom kiseline i propuhivanjem sa sintetskim zrakom) se pomoću visoke temperature (680 °C) oksidira u prisutnosti katalizatora (Pt). Pritom se svi ugljikovi spojevi prevode u ugljikov dioksid koji se detektira infracrvenim detektorom (NDIR). Svi dobiveni rezultati zadovoljavaju postavljene kriterije prihvatljivosti. Iz toga se može zaključiti da je metoda prikladna opisanoj svrsi.Total Organic Carbon - TOC is the sum of organically bound carbon present in water, bonded to dissolved or suspended matter. TOC is the measure of the level of organic molecules or contaminants in purified water. Therefore, it shows how much the water sample is contaminated by organic pollutants. In the thesis there are described different types of TOC determination. The purpose of this thesis is the validation of analytical method for determination of total organic carbon in water. Method validation is the process used to confirm that the analytical procedure employed for a specific test is suitable for its intended use. This thesis deals only with partial validation. Determined validation parameters are: linearity, limit of detection, limit of quantification, precision and accuracy. The method principle is the following: first of all, inorganic carbon is removed by acidification and purging with synthetic air. The purified water sample is then oxidized by combustion (680 °C) with added catalyst (Pt). At last, all carbon compounds are oxidized to carbon dioxide that is then detected by non-dispersive infrared detector (NDIR). The results obtained show that the method is suitable for intended use
Quaternary salts of pyrinide derivatives
No full textOvaj završni rad pregled je već postojećih saznanja o heterocikličkim spojevima među kojima se u radu ističe piridin, o derivatima piridina, kvaternim amonijevim solima te reakciji kvaternizacije. Kvaterne amonijeve soli su zbog svojih raznolikih svojstava, jednostavne pripreme i višestruke primjene predmet istraživanja mnogih znanstvenika već dugi niz godina. Kvaterni amonijevi spojevi, uključujući piridinijeve soli, u brojnim su istraživanjima pokazali širok spektar zanimljivih bioloških aktivnosti, uključujući i djelovanje kao reaktivatori ljudske eritrocitne acetilkolinesteraze i butirilkolinesteraze inhibirane bojnim otrovima i pesticidima. Pregled nekoliko sinteza kvaternih soli derivata piridina uvodi u eksperimentalni dio ovoga rada u kojem su izvedene tri reakcije kvaternizacije derivata piridina (nikotinamida i piridoksal-oksima) s 2-brom-4'-fluoracetofenonom i 2-brom-4'-metoksiacetofenonom.This work is a review of already existing knowledge about heterocyclic compounds, primary including pyridine and it's derivatives, quaternary ammonium salts and quaternization reactions. Due to their diverse properties, simple preparation and multiple applications, quaternary ammonium salts are the subject of research by many scientists for many years. Quaternary ammonium compounds, including pyridinium salts, have shown a wide variety of interesting biological activities, among others they act as reactivators of human erythrocyte acetylcholinesterase and butyrylcholinesterase inhibited by nerve agents and pesticides. An overview of a few synthesis of quaternary salts of pyridine derivatives introduce the experimental part of this paper, in which three quaternization reactions of pyridine derivatives (nicotinamide and pyridoxal oxime) with 2-bromo-4'-fluoroacetophenone and 2-bromo-4'-methoxyacetophenone were carried out
Mitochondrial DNA mutations
No full textMitohondriji su "energetska centrala stanice", odnosno stanični organeli kojima je glavna uloga proizvodnja energije neophodne za odvijanje svih staničnih procesa (rast, razvoj, metabolizam i dr.). Ove su organele značajne i po tome što sadrže vlastiti DNA materijal. U mitohondrijima, također, dolazi i do stvaranja reaktivnih kisikovih vrsta (ROS), agresivnih čestica koje uzrokuju oštećenja mitohondrijske DNA, (mtDNA), odnosno mitohondrijskog genoma. Kao posljedica oštećenja nastaju mutacije mtDNA koje uzrokuju nastanak teških i rijetkih multisistemskih mitohondrijskih poremećaja, sindroma i bolesti koji su većinom specifični za određenu dobnu skupinu. Budući da se mtDNA nasljeđuje od majke, kod mitohondrijskih se bolesti radi o tzv. majčinskom nasljeđivanju. Mutacije mtDNA zahvaćaju brojna tkiva čije energetske potrebe u velikoj mjeri određuju stupanj prisutnosti mutacija. Stoga, bolesti uzrokovane mutacijama mtDNA najčešće pogađaju središnji živčani sustav i mišiće. U ovom će se radu pobliže opisati struktura i funkcija mitohondrija, struktura i nasljeđivanje mtDNA, kao i njihove mutacije i uloga u razvoju mitohondrijskih bolesti.Mitochondria are "central energy station" of the cell, a cellular organelles whose most important role is the production of energy necessary for all cellular processes (cellular growth, development, metabolism, etc.). Significance of these organelles is that they contain their own DNA material. Also, reactive oxygen species (ROS), aggressive particles that cause mitochondrial DNA (mtDNA) damage, i.e. the damage of mitochondrial genome, are produced in mitochondria. As a damage result, mtDNA mutations occur and cause the onset of severe and rare multisystem mitochondrial disorders, syndromes and diseases which are usually specific for a particular age group. Since mtDNA is inherited exclusively from mother, mitochondrial diseases are associated with so-called maternal inheritance. mtDNA mutations are present in many tissues, where the energy needs of these tissues largely determine the level of their presence. Therefore, diseases caused by mutations of mtDNA most often affect the central nervous system and muscles. In this work, the structure and function of mitochondria, structure and inheritance of mtDNA, as well as their mutations and the role in development of mitochondrial diseases, are studied
Rheological characterization of self-assembled gel structures
No full textPripremljeni su samouređujući gelovi miješanjem 2 mL i 1 mL modificiranih silikatnih nanočestica koncentracije 0,01825 g/mL te 4% otopinom alginata. Silikatne nanočestice su pripremljene Stöberovom metodom iz tetraetil ortosilikata dodatkom amonijaka. Kako bi odredio optimalan pH za nastajanje gela pogodnih karakteristika, izmjeren je zeta potencijal u ovisnosti o pH vrijednosti. Dobiveni gelovi su reološki karakterizirani kako bi se dokazala tiksotropija. Iz dobivenih mjerenja se pokazalo kako je optimalan pH za dobivanje gela pogodnih reoloških svojstava 7, a volumen dodanih modificiranih silikatnih nanočestica 1 mL. Gel pripremljen s 2 mL modificiranih silikatnih nanočestica je imao veću početnu viskoznost zbog većeg broja veza koje nastaju prilikom umrežavanja.Self-assembled gel structures were prepared by mixing 1 mL and 2 mL of modified silica nanoparticles concentration 0.01825 g/mL with 4 % solution of alginate. Silica nanoparticles were prepared with Stöber synthesis from tetraethyl orthosilicate adding ammonia solution. For determination of optimal pH value, zeta potential on different pH values was measured. Obtained gels were rheological characterized to demonstrate thixotropy. Obtained measurements showed that optimal pH value is 7, and volume of added modified silica nanoparticles is 1 mL. Gel prepared by adding 2 mL of modified silica nanoparticles have higher initial viscosity. The main reason for that is higher number of bonds formed when gel framework is made
Development of a synthetic method for the preparation of a-O-mannoside of acetic acid
No full textUgljikohidrati su važne organske makromolekule koje se uglavnom spominju u kontekstu izvora energije, dok se rjeđe tumače njihove esencijalne uloge u biološkim sustavima. Oligosaharidi nose informacije koje su određene mjestom vezanja monosaharida, konfiguracijom glikozidne veze (α- ili β-) te udjelom razgranatosti, što ih čini izvrsnim prenositeljima biološke informacije. Lektini su proteini koji specifično vežu šećerne strukture. Poseban tip lektina su manozni receptori koji su prisutni na površini različitih imunokompetentnih stanica te su potencijalne mete za vezanje manoziliranih antigena. Također se mogu koristiti za unos lijekova koji u svojoj strukturi sadrže manozu, te utjecati na tijek reakcija u imunološkom sustavu. Cilj ovog rada je razvoj metode priprave manozilirane karboksilne kiseline, važne podstrukture u sintezi spoja koji bi bio potencijalni adjuvant. Acetiliranjem D-manoze anhidridom octene kiseline uz jod kao katalizator, pripravljena je 1,2,3,4,6- penta-O-acetil-α,β-D-manopiranoza kojoj je selektivno uklonjena anomerna acetatna zaštita na tri različita načina te je dobivena 2,3,4,6-tetra-O-acetil-α-D-manopiranoza. U trećem koraku je pripravljen O-manozid reakcijom tetraacetilirane manoze s tert-butil-bromacetatom i kalijevim karbonatom pri čemu je preferirano nastao α-anomer O-manozida. Anomerno čistom esteru uklonjena je tert-butilna zaštita pomoću trifluoroctene kiseline u suhom diklormetanu čime je pripravljena 2-(2,3,4,6-tetra-O-acetil-α-Dmanopiranoziloksi) octena kiselina u dobrom prinosu, a strukture produkata su okarakterizirane NMR i NMR spektroskopijom.Carbohydrates are important organic macromolecules mainly referred to in the context of energy sources, while their essential role in biological systems is rarely interpreted. Information carried in oligosaccharides is determined by the site of the monosaccharide binding s, the configuration of glycosidic bond (α- or β-) and the amount of branching. All this makes them excellent transmitters of biological information. Lectines are proteins that specifically bind sugar structures. A special type of lectins are mannose receptors present on the surface of different immunocompetent cells and are potential targets for binding mannosylated antigens. They can also be used for injection of drugs containing mannose and thus affect the progress of specific reactions in the immune system. The aim of this paper is to develop a method for the preparation of mannosylated carboxylic acid, an important substructure in the synthesis of the compounds used as potential adjuvants. Acetylation of D-mannose with anhydride of acetic acid and iodine as catalyst gave 1,2,3,4,6-penta-O-acetyl-α, β-D-mannopiranose. Anomeric acetate protection, was selectively removed from the obtained compound using three different ways, all resulting in formation of 2,3,4,6-tetra-O-acetyl-α-D-mannopyranose. In the third step, O-mannoside was prepared by reacting tetraacetylated mannose with tert-butyl bromoacetate and potassium carbonate. This reaction gave preferably an α-anomer of O-mannoside. Tert-butyl protection was removed from the pure α-anomer using trifluoroacetic acid in dry dichloromethane giving 2-(2,3,4,6-tetra-O-acetyl-α-D-manopyranosyloxy) acetate in a good yield. The products structures were characterized by and NMR spectroscopy
Synthesis of Neutral Complxes of Copper and Vanadium with Hydroxypyrones
No full textGlavni cilj ovog rada jest sinteza neutralnih kompleksa bakra i vanadija s hidroksipironima. Uz poznata svojstva bakra i vanadija kao i svojstva njihovih soli korištenima u sintezi, analizirana su svojstva hidroksipirona, a ponajviše kumalične kiseline koja je jedan od najčešćih reaktanata u reakcijama. Osim sinteze, u radu će se raspravljati i o analizi dobivenih kompleksa pomoću elementne analize (CHN), infracrvene spektroskopije s Fourierovom transformacijom (FTIR) i simultane termalne analize (TGA/DSC).The main goal of this work is the synthesis of neutral complexes of Copper and Vanadium with Hydroxypyrones. The aim is to get acquainted with properties of particular metals and their salts used in the synthesis, and also with properties of hydoxypyrones especially Coumalic acid which is a starting material. Moreover, except synthesis, the elemental analysis (CHN) as well as Infrared Spectroscopy (FTIR) and Thermogravimetric analysis (TGA) of obtained products is described