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Synthesis of quaternary ammonium salts of piperidine with potential antibactericidal activities
No full textU organskoj kemiji je velik broj spojeva sa dušikom. On je zajedno s kisikom, halogenim elementima, fosforom i sumporom jedan od "heterogenih" elemenata. Spojevi koji sadrže dušik se zovu amini. Međusobno se razlikuju po substituiranosti dušikova atoma i tako se dijele na: primarne, sekundarne, tercijarne i kvarterne koji se još nazivaju i kvaterne amonijeve soli koji se i opisuju u ovom radu. Iz opće formule je vidljivo da su spojevi kvaternih amonijevih soli dipoli. Pozitivni naboj se nalazi na dušiku, a negativni na halogenom elementu koji je označen kao X. Alkilne skupine (R) mogu biti raznih vrsta i veličina, no da bi se spoj ponašao kao površinski aktivna tvar jedna alkilna skupina mora sadržavati dugački ugljikov lanac. Taj lanac je hidrofoban dio molekule, dnosno bez naboja. Drugi dio molekule sadrži naboj i interferira sa polarnim tvarima kao što je voda ili slično polarno otapalo. Zbog strukturnih svojstava molekule kvaterne amonijeve soli imaju utjecaj na lipide koji izgrađuju membranu bakterija. Taj utjecaj na bakterije je jednim djelom opisan u daljnjem tekstu. Kvaterne amonijeve soli su u većini slučajeva sintetski spojevi jer su vrlo korisni kao antibaktericidi, omekšivači tkanina i sredstva za uklanjanje nečistoća odnosno površinski aktivne tvari. U eksperimentalnom dijelu ovog rada sintetiziran je jedna kvaterna amonijeva sol. Po strukturi je sličan površinski aktivnim tvarima, odnosno sadrži pozitivno nabijenu "glavu" i hidrofobni ugljikovidični "rep". Procesi sinteze i izolacije su opisani u daljnjem tekstu kao i karakterizacija.There is large number of compound which contain nitrogen. It is with oxygen, halogens, phosphate and sulfur one of "hetergenic" elements. That large group of organic compound that contain nitrogen is called amines. They differ from eachother by supstitution of nitrogen atom and classified ass primary, secundary, tertiary and quaternary also known as quaternary amonium salts which have main word in this experiment. General formula show us that QACs are dipoles. Pozitive charge bears nitrogen atom and negative charge is on halogen (X). Alkyl groups (R) can be all kinds of shape and length, but one of them must have long alkyl chain. That chain is hidrifobic part of molecule, without any charge. Second part h bears charge and interact with polar substances like water or similar solvent. Because of their structural properties, QACs have influence on lipids which build bacterial membrane. That influence is described in further text. QACs are mostly synthetic because they are very helpful as antibiotics, fabric softeners and stain removers known as surface aktive substances or surfactants. In this experimet one compoun of that kind is synthesized. The structure is similar to surfactants, contains positively charged "head" and hydrofobic "tail". Synthesis and izolation are described in further text and characterization also
Study of the electrochemical properties of rutin in different inert electrolytes
No full textU ovom radu je opisano ispitivanje elektrokemijskih svojstava rutina (3`,4`,5,7-tetrahidroksiflavon--rutinozida) u tri različita inertna elektrolita: KCl, NaCl i LiCl. Mjerenja su izvedena pomoću diferencijalne pulsne voltametrije. Iz voltamograma je vidljivo da struja i potencijal oksidacijskih strujnih vrhova rastu s porastom koncentracije rutina. Najbolji kalibracijski dijagram je dobiven u otopini s kalijevim kloridom kao inertnim elektrolitom, pa je za određivanje nepoznate koncentracije rutina u ekstraktu kore jabuke Zimnjare korišten taj kalibracijski dijagram. Određena koncentracija rutina u ispitivanom ekstraktu iznosi 18,7∙ mol .In this work, a study of electrochemical characterizations of rutin (3',4',5,7-tetrahydroxyflavone--rutinoside) in three different inert electrolytes: KCl, NaCl and LiCl is described. Measurements were performed by differential pulse voltammetry. Voltammograms have shown that current and potential were increasing with the increase of rutin concentration. The best calibration diagram was obtained in solution with potassium chloride as inert electrolyte, so this calibration diagram was used for determination of rutin concentration in an apple peel extract of Zimnjara. Concentration of rutin in apple peel extract is 18,7∙ mol
Mutation of keratin gene in skin diseases
No full textKoža je najveći i najteži organ ljudskog organizma. Upravo ona čini granicu, barijeru, između organizma i okoliša čime se uviđa i njena primarna uloga, odnosno zaštita. Koţž štiti organizam od negativnih okolišnih čimbenika kao što su UV zračenje ili razni mikroorganizmi, ali istovremeno i sprječava gubitak tjelesnih tekućina i elektrolita iz istog. Građena je od triju slojeva od kojih je površinski sloj, epidermis, strukturno izgrađen od stanica ispunjenih keratinom. Keratini tvore multifunkcionalne proteine koji pružaju mehaničku stabilnost kože te su posrednici regulacije brojnih procesa kao što su stanična polarnost, migracija, sinteza proteina ili osjetljivost na apoptozu. Keratini su vlaknasti proteini koji su primarno izraženi u epitelnom tkivu, koži i kosi. Međutim, identificirane su brojne mutacije gena keratina koje mogu rezultirati krhkošću stanica i tkiva, zadebljanjem površinskog sloja kože (hiperkeratozom) te brojnim drugim patološkim promjenama na koţi tzv. eflorescencijama. Keratini zadržavaju svoju ekspresiju specifičnu za određeni tip stanice što ih čini izvrsnim markerima različitih bolesti. Prilikom liječenja kožnih oboljenja nastalih mutacijama gena keratina na raspolaganju stoji niz lijekova koji se svrstavaju u skupine lokalne i opće terapije, ali najistaknutiji su keratolitici i retinoidi.Skin is defined as the largest and most severe organ of the human body. It is precisely what makes the limit, barrier, between the organism and the environment, thus seeing the main stake or protection. The skin protects the organism against negative environmental factors such as UV radiation or various microorganisms, but at the same time prevents the loss of body fluids and electrolytes from the same. It is constructed of three layers of which the surface layer, epidermis,is structurally constructed of cells filled with keratin. Keratines form multifunctional proteins that provide mechanical stability of the skin and are mediators of regulation of numerous processes such as cellular polarity, migration, protein synthesis or apoptosis sensitivity. Keratin are fiber proteins that are primarily expressed in epithelial tissue, skin and hair. However, numerous keratin-induced mutations have been identified, which can results by cell and tissue fragility, thickening of the skin's superficial layer (hyperkeratosis) and numerous other epidermal lesions,respectively pathological changes in the skin. Keratines retains its specific type-specific expression, which makes them excellent components or disease markers. In the treatment of skin diseases caused by keratin mutations, a variety of drugs are included in the local and general therapeutic groups, but the most significant are keratolytics and retinoids
Determination of protein concentration and a comparison of Bradford, Lowry and Biuret methods
No full textOdređivanje koncentracije proteina u uzorku bitan je korak svake analize. Danas su poznate razne metode kvantifikacije proteina, ali klasične spektrofotometrijske metode, kao što su Biuret, Lowry i Bradford metoda, najčešće su korištene metode u biokemijskim i medicinskim istraživanjima. Sve metode imaju prednosti i nedostatke, a temelje se na reakciji metalnih iona i boja s proteinima, pri čemu nastaje produkt karakteristične boje čija se apsorbancija prati na određenoj valnoj duljini.. Mjerenje apsorbancije za Biuret metodu je na valnoj duljini od 540 nm, te na 595 nm za Lowry i Bradford metodu. Cilj ovoga rada je ispitati i usporediti osjetljivost Biuret, Lowry i Bradford metode za određivanje koncentracija proteina izoliranih iz humanih stanica karcinoma vrata maternice, poznatih pod nazivom HeLa stanice. Koncentracija proteina određena je i modificiranom Bradford metodom, gdje se za pripremu Bradford reagensa, umjesto CBB G-250 koristila CBB R-250. Najviše koncentracije proteina određene su modificiranom Bradford metodom, dok su korištenjem komercijalnog Bradford reagensa izmjerene najniže koncentracije. Također, opisan je i metodički dio na temu "Aminokiseline i proteini" za 4. razred srednje škole koji sadrži pisanu pripremu za nastavni sat, radni listić, te dva pokusa. Ova nastavna tema obrađuje se kombinacijom frontalnog rada i grupni rada (izvođenje predviđenih pokusa u 4 skupine).Determination of protein concentration in a simple is a important step in every analysis. Today different methods for quantitation of protein are developed, but classic spectrophotometric methods, such as Biuret, Lowry i Bradford method, are the most often used in biochemical and medical research. All methods have some advantages and disadvantages, and they are based on reaction of metal ions and dye with proteins to give caracteristically coloured product. Measurment of absorbance are preformed at wavelenght of 540 nm for Biuret method, and at 595 nm for Lowry and Bradford method. The aim of this study is determine and compare sensitivity of Biuret, Lowry i Bradford method fod determination of concentration of proteins, which are isolated from human cervical carcionoma cells, also known as HeLa cells. Concentration of proteins are also determined by modified Bradford method, where for preparation of Bradford reagent, CBB R-250 are used instead of CBB G-250. The highest concentration of proteins are determined by modified Bradford method, but the lowest concentration are determined by use commercial Bradford reagent. This thesis also contains a part with teaching methods on high school level including printed preparation for lesson "Aminoacids and proteins", corresponding working papers and two experiments for group work. This lesson is prefomed through combination of a lecture and group work (students are divided into 4 groups and they preform two experiments)
Preparation of oximes in choline chloride based eutectic solvents
No full textDanas sve više postajemo svjesni štetnog učinka kojeg klasična kemijska sinteza ima na okoliš i zdravlje ljudi. Upravo zbog toga, snažno se razvija nova kemija tzv. "zelena" kemija koja za cilj ima razvoj novih, sigurnijih i energetski učinkovitijih procesa te primjenu neopasnih otapala. Prema "zelenoj" kemiji idealno bi otapalo trebalo biti jednostavno pripraviti, otapalo bi trebalo biti fizički i kemijski stabilno, niske hlapljivosti te jednostavno za recikliranje uz mogućnost ponovne upotrebe. Veliku su pozornost zbog svojih svojstava privukla eutektička otapala, koja se danas sve više koriste kao zamjena za uobičajena organska otapala. Cilj ovog rada bio je pripraviti eutektička otapala na bazi kolin-klorida te ispitati mogućnost priprave oksima u eutektičkim otapalima na bazi kolin-klorida. Oksimi su organski spojevi opće formule =NOH, gdje je bočni organski lanac, a može biti vodik ili neka druga skupina.Today, we are increasingly aware of the adverse effect that classical chemical synthesis has on the environment and human health. For this very reason, a new chemistry so-called green chemistry is developing strongly to develop new, safer and more energy-efficient processes and the application of non-hazardous solvents. For "green" chemistry ideally the solvent should be easy to prepare, the solvent should be physically and chemically stable, low volatility and easy to recycle with the possibility of reuse. Great attention due to its properties attracted eutectic solvents, which are increasingly used today as a substitute for common organic solvents. The aim of this paper was to prepare choline-chloride based deep eutectic solvents and to investigate the possibility of making oximes in choline-chloride based deep eutectic solvents. Oximes are organic compounds with the general formula =NOH, where is an organic side-chain and may be hydrogen or another organic group. Oxymes are used for the protection and purification of carbonyl compounds in organic synthesis
Synthesis of piridinones and it"s derivatives from pyranones
No full textU ovom radu opisana je priprava spoja 3, 1-(m-aminofenil)-3-hidroksi-2-metilpiridin-4-ona u različitim reakcijskim uvjetima. Spoj 3 pripada skupini 3-hidroksipiridin-4-ona a u svojoj strukturi sadrži slobodnu amino i hidroksilnu skupinu. Kao polazni reagens za sintezu spoja 3 korišten je 3-hidroksi-2-metilpiran-4-on (maltol) koji pripada skupini 3-hidroksipiran-4-ona. U ovom radu provedene su 4 sinteze spoja 3 koje podrazumijevaju promjenu reakcijskih uvjeta (autoklav, refluks) te promjenu vrste kiselog katalizatora (p-TsOH, HCl). Strukture spojeva su pretpostavljene IR spektroskopijom.In this paper, the preparation of compound 3, 1-(m-aminophenyl)-3-hydroxy-2-methylpyridin-4-one under various reaction conditions is described. Compound 3 is one representative of 3-hydroxypyridin-4-ones and in its structure contains a free amino and hydroxyl group. As a starting material for the synthesis of compound 3 3-Hydroxy-2-methylpyran-4-one (maltol), one representative of 3-hydroxypyran-4-ones, was used. In this paper, 4 syntheses of compound 3 were carried out, which imply a change in reaction conditions (autoclave, reflux) and change of acid catalysts (p-TsOH, HCl). The structure of the compounds was assumed by IR spectroscopy
Determination of response characteristics of ion-selective electrode modified with nanoparticles
No full textTenzidi su bifunkcionalni organski spojevi koji smanjuju površinsku napetost otopine u kojoj se nalaze. Sastoje se od hidrofilnog i hidrofobnog dijela. Hidrofilna skupina može biti pozitivno ili negativno nabijena, dok je hidrofobna skupina dugački ugljikovodični lanac koji nema naboja.Prema hidrofilnim skupinama u strukturi molekula i njihovom elektrokemijskom ponašanju tenzidi se svrstavaju u četiri glavne kategorije: anionski, kationski, neionski i amfolitski tenzidi. Najčešće metode za određivanje tenzida su titracijske metode, a najkorištenija metoda za određivanje koncentracije tenzida je poteonciometrijska titracija. Elektrode za ispitivanje koncentracije tenzida mogu biti modificirane nanočesticama koje poboljšavaju svojstva elektrode. U eksperimentalnom dijelu rada ispitan je odziv tenzidno selektivne elektrode modificirane nanočesticama na nekoliko anionskih tenzida u natrijevu sulfatu i destiliranoj vodi. Mjerenja su izvršena s Philips elektrodom koja u membrani sadrži ionski par tetraoktadecilamonijev tetrafenilborat (TODA-TPB) modificiran višestjenčanim ugljikovim nanočesticama (MWCNT, eng. multi-walled carbon nanotubes).Surfactants are bifunctional organic compounds that reduce the surface tension of the solution in which they are found. They consist of a hydrophilic and a hydrophobic part. The hydrophilic group may be positively or negatively charged, while the hydrophobic group is a non-charged hydrocarbon chain. According to the hydrophilic groups in the molecular structure and their electrochemical behavior, the surfactants are classified into four major categories: anionic, cationic, nonionic and ampholytic surfactants. The most common methods for determination of surfactatnts are titration methods, and the most commonly used is potentiometric titration. Electrodes for determination of surfactants concentration can be modified by nanoparticles that improve their properties. In the experimental part, the response characteristics of surfactant selective electrode modified with nanoparticles were investigated in water and sulfate solutions of several anionic surfactants. on several anionic surfactants in sodium sulphate and distilled water was tested. The measurements were performed usinga Philips electrode with membrane based on tetraoctadecylamonium tetraphenylborate (TODA-TPB) ion pair, andmodified by multi-walled carbon nanotubes (MWCNT)
Methodes for proteinpurification
No full textU stanici postoji na tisuće vrsta proteina, a svaki od njih ima svoju funkciju. Upravo zato, da bismo istražili njihova svojstva i funkcije, potrebno ih je najprije izolirati iz stanice, a nakon toga pročistiti. Dok velike proteine nije teško izolirati i pročistiti iz stanice, za izolaciju i pročišćavanje malih proteina potreban je veliki broj koraka i različitih tehnika. U ovom radu opisat ćemo upravo tehnike izolacije i pročišćavanja proteina iz različitih stanica i tkiva.There are thousands of types of proteins in the cell, and each of them has a different function. That is why, in order to investigate their properties and functions, it is necessary to first isolate them from the cells and then purify them. While large proteins are not difficult to isolate and purify from the cell, isolating and purifying small proteins requires a large number of steps and techniques. In this paper we will describe the techniques of isolation and purification of proteins from different cells and tissues
Molecular methods in allergen characterization
No full textU današnjoj modernoj civilizaciji sve se češće javljaju alergije. Alergije obuhvaćaju određene reakcije ljudskog tijela na neke tvari što se opisuje kao preosjetljivost organizma (preosjetljivost tipa I) na neke tvari. Kada je organizam preosjetljiv na neku tvar, on ju prepoznaje kao antigen i počinje stvarati odgovarajuća antitijela. Takve se tvari, koje organizam prepoznaje kao antigene, nazivaju alergenima. Tek se početkom 20. stoljeća javljaju prvi pokušaji razumijevanja alergijskih bolesti kada su se pripravljali ekstrakti alergena u dijagnostičke i terapeutske svrhe. U ovom završnom radu istraţeno je djelovanje alergena u organizmu te su opisane molekularne metode koje se koriste u karakterizaciji alergena pregledom novije znanstvene literature.In todays modern civilization, allergies have become the most common thing. Allergies are certain reacions of human body to some substances which can be also described as hypersensitivity of organism (Type I allergy) to some substances. When he organism is too sensitive to a substance, it recognizes a subsance as an antigen and starts producing corresponding antibodys. These substances, recognized as anigenes, are called allergenes. It wasn't up until the beginning of the 20th century when the first atempts of understanding allergic diseases have been developed where allergen extracts have been developed for diagnostic and therapeutic purposes. In this thesis activity of allergens in human organism and molecular methods in characterization of allergens will be described and explored by the means of new scientific papers
Tumor suppressor genes in breast cancer
No full textRak dojke je najčešća zloćudna bolest u žena u razvijenim zemljama svijeta. Iako mehanizam nastajanja raka dojke još uvijek nije u potpunosti razjašnjen, epidemiološka istraživanja utvrdila su razne rizične čimbenike za obolijevanje od ove bolesti, među kojima se razlikuju negenetski i genetski čimbenici. Utvrđeno je da dvije skupine gena imaju ključnu ulogu u indukciji raka, to su onkogeni i tumor supresorski geni. Danas je poznato deset tumor supresorskih gena, koji su uključeni u regulaciju genomskog sadržaja, povezanih s rakom dojke. Tu pripadaju TP53, BRCA1, BRCA2, ATM, RAD50, PTEN, APC, CDH1, RB i PALB2. Mutacije u BRCA1 i BRCA2 genima povezane su s obiteljskim nasljeđivanjem raka dojke, te predstavljaju visoki rizik ranog obolijevanja od ove bolesti. Iako se funkcije ovih gena znatno razlikuju svi su oni uključeni u popravke oštećenja DNA i održavanje genomske stabilnosti. Mutacije koje nastaju na tumor supresorskim genima uzrokuju gubitak njihove funkcije i moguće je da je upravo taj mehanizam ključan za razvoj raka dojke. U ovome radu pobliže ću opisati svojstva i funkcije nekih tumor supresorskih gena, njihov doprinos razvoju raka dojke, ujedno ću spomenuti ulogu hormona i negentetskih čimbenika te važnost tumorskih markera pri dijagnostici i liječenju ove zloćudne bolesti.Breast cancer is the most common malignant disease in women in developed countries in the world. Although the mechanism of breast cancer development has not yet been fully clarified, epidemiological research has identified various risk factors for the developmentof this disease, where the not genetic and genetic factors play a significant role. It was found that two groups of genes play a key role in inducing cancer, namely oncogenes and tumor suppressor genes. Today, ten tumor suppressor genes, involved in the regulation of genomic contents, are associated with breast cancer. These include TP53, BRCA1, BRCA2, ATM, RAD50, PTEN, APC, CDH1, RB and PALB2. Mutations in BRCA1 and BRCA2 genes are associated with family breast cancer syndrome, and represent a high risk of early breast cancer development. Although the functions of these genes differ significantly, they are all involved in DNA damage repair and maintainenc of genomic stability. Mutations occuring in tumor suppressor genes cause loss of their function and it is possible that this is the mechanism crucial to the development of breast cancer. In this paper I will describe in more detail the properties and functions of some tumor suppressor genes, their contribution to the development of breast cancer, as well as the role of hormones, external factors and the importance of tumor markers in the diagnosis and treatment of this malignant disease