PREVENTION OF GENOTOXIC EFFECT OF OCHRATOXIN A AND AFLATOXIN B1 BY ECHINACEA PURPUREA EXTRACTS

The aim of this work was to examine the polyphenol content in Echinacea purpurea (L.) Moench extracts and to determine their antioxidant and antigenotoxic effect. The antioxidant activity of extracts and main components is determined by the application of electronic spin resonance and spectophotometric methods of capturing DPPH, superoxide and hydroxyl radical. The antigenotoxic effect was evaluated with genotoxic mycotoxins – aflatoxin B1 (AFB1) and ochratoxin A (OTA). Herbe ehinacea extract contained 13.31% of total polyphenols. Ehinacea extract contained a sufficient amount of phenolic acids (primarily chicoric and caftaric acid). Ehinacea extract showed the ability to neutralize DPPH radicals (EC50 = 15.67 μg/mL). Similar results were also identified by testing the capture of hydroxyl and superoxide radicals. The strong antioxidant activity of the dominant components that indicate phenolic acids as the ingredients that contribute the most to the antioxidant and antigenotoxic effect of echinacea extract was also found. Genotoxic suppression of AFB1 and OTA was established by a comet test, establishing a significant reduction in tail, tail intensity and tail torque in leukocytes co-treated with mycotoxins and different concentrations of extracts

SURGICAL APPROACH TO ATYPICAL WOUNDS (CLINICAL CASES). SUBCUTANEOUS ISCHEMIC ARTERIOLOSCLEROSIS (MARTORELL ULCER, CALCIPHYLAXIS, EUTROPHICATION)

U suvremenoj se kirurgiji liječenje atipičnih rana postavlja kao jedan od najdelikatnijih zahtjeva. Prikazujemo dva recentna klinička slučaja iz naše ustanove kao rijedak primjer vaskularnih atipičnih rana - posljedice akutne supkutane ishemičke rterioloskleroze. S obzirom na iznimno sličnu patofiziološku podlogu, pristup i liječenje Martorellovog hipertenzivnog vrijeda i kalcifilaksije su slični. Dodatnu težinu bolesti zbog u jednom dijelu vrlo slične kliničke slike drugim atipičnim ranama, daje činjenica da se pogrešnim liječenjem mogu uzrokovati teške lokalne i sistemske infekcije s nerijetko tragičnim ishodima. na temelju tipičnih lokalizacija, nekrotičnih i vrlo bolnih nekroza/eshara, progresivnog deteriorirajućeg tijeka i često sekundarne teške infekcije zajedno s anamnezom dugotrajne hipertenzivne bolesti i dijabetesa – može se pobuditi sumnju na ishemičku supkutanu arteriolosklerozu. Ciljana patohistološka analiza, anamneza, laboratorijske pretrage i lokalni status mandatorni su za pravilno dijagnosticiranje i moguće potpuno izliječenje. osim sistemskog liječenja, agresivan i minuciozan redoviti kirurški debridement, zajedno s terapijom negativnim tlakom i transplantacijom kože omogućuje rapidno zacijeljenje tih atipičnih ulceracija.Atypical wounds are probably the most delicate modern medicine topics as well as the most demanding surgical issue. Recently, we submitted an original report of two similar atypical vascular cases at our surgery department. Both presented a rare type of atypical, potentially fatal, vascular illness due to acute ischemic subcutaneous arteriolosclerosis. Because of the strikingly similar common pathophysiological features, Martorell hypertensive ischemic leg ulcer (HYTILU) and calciphylaxis require identical approach and therapy, both systemic and surgical. Even an experienced clinician can easily confuse it with other atypical wounds, namely pyo derma gangrenosum, which due to the corticosteroid induced immunodeficiency can be detrimental, since the two different approach strategies are required. Based on typical localization, necrotic painful skin necroses, progressive local deterioration, often difficult secondary infections along with long term hypertension and diabetes history could elucidate suspicion of ischemic subcutaneous arteriosclerosis. Hypertension (and often diabetes), local findings and histologically proven subcutaneous arteriolosclerosis are mandatory to make the diagnosis. Rapid local amelioration following correct treatment approach additionally confirms the presumed diagnosis. Besides the minutely repetitive surgical debridement, negative wound pressure therapy and split skin transplantation, one should consider systemic medication (analgesics, antioxidants, LMWH, sodium thiosulfate and antibiotics). Considering the cases presented, opportune decisions along with moderate aggressive and modern holistic surgical approach should inevitably resolve hard to heal atypical wounds

OXIDATIVE STRESS UNDER INTENSE PHYSICAL EXERTION IN HUMANS AND ANIMALS

Poremećaj ravnoteže u organizmu između proizvodnje reaktivnih kisikovih radikala (ROS) i antioksidansa nazivamo oksidacijskim stresom. Do pomaka ravnoteže dolazi ukoliko je smanjena antioksidacijska obrana organizma ili ako je povećano stvaranje slobodnih radikala. Antioksidansi su sve one tvari koje u maloj količini u kratkome vremenu neutraliziraju djelovanje slobodnih radikala i drugih oksidansa. Oni nastaju u stanici ili se u organizam unose hranom ili u obliku dodataka. Antioksidansi onemogućuju stvaranje slobodnih radikala u organizmu, uništavaju stvorene slobodne radikale ili popravljaju oštećenja u stanici nastala djelovanjem slobodnih radikala.U radu su prikazani biomarkeri oksidacijskog stresa u ljudi i životinja, prema podjeli na enzimske, neenzimske, te ostale biomarkere s naglaskom na biomarkere umora perifernih mišića. Biomarkeri umora perifernih mišića u ljudi i životinja su markeri staničnog mišićnog oštećenja i pokazatelji mišićnog stresa, a koriste se za uvid u mehanizme iscrpljenosti tijekom vježbanja kako bi se otkrio povećani umor ili se otkrili manjkavi metabolički putevi. Utvrđivanje oksidacijskog stresa važno je zbog mogućnosti pravovremenog uključivanja antioksidacijskih tvari koji povećavaju antioksidacijski kapacitet ljudskog i životinjskog organizma.Oxidative stress indicates an imbalance in the body between pro-oxidant and antioxidant in favor of a pro-oxidant. To shift the balance may occur if the reduced antioxidant defense of the body or if the increased production of free radicals. Antioxidants are those substances that in a small amount in a short time can neutralize free radicals and other oxidants. They are produced in the cell or organism in food intake or in the form of dietary antioxidants in food or liquid to drink. Antioxidants prevent the formation of free radicals in the body, destroying free radicals created or repair damage in cells caused the action of free radicals. Paper showed biomarkers of oxidative stress in humans and animals, divided to enzymatic, non-enzymatic and other. Biomarkers of peripheral muscle fatigue in humans and animals are markers of cellular muscle damage and muscle stress indicators, and are used for insight into the mechanisms of fatigue during exercise to detect increased fatigue or found deficient metabolic pathways. The determination of oxidative stress is important because of the possibility of timely inclusion of antioxidant substances that increase the antioxidant capacity of human and animal organism

Ružička days : International conference 16th Ružička Days “Today Science – Tomorrow Industry” : Proceedings

Proceedings contains articles presented at Conference divided into sections: open lecture (1), chemical analysis and synthesis (3), chemical and biochemical engineering (8), food technology and biotechnology (8), medical chemistry and pharmacy (3), environmental protection (11) and meeting of young chemists (2)

Analysis of gas engine characteristics for generator drive

U diplomskom radu opisan je nulto-dimenzionalni model plinskog motora Waukesha H24GL s prednabijanjem. Ukratko su opisani i simulacijski modeli motora, te prednosti i nedostaci pojedinih tipova modela. Opisani su matematički modeli svakog od glavnih dijelova motora koji su međusobno povezani u jednu cjelinu. Model motora je izrađen po uzoru na industrijski osamcilindrični, linijski plinski motor s prednabijanjem. Opisano je stvaranje gorive smjese, te problematika zakašnjenja paljenja pri izgaranju i posebno stvaranje gorive smjese kod Ottovih plinskih motora. Dan je opis optimizacije performansi motora te utjecaj varijabilnog otvaranja ventila te poboljšanje performansi turbopuhalom. Dan je sažeti tehnički opis glavnih dijelova i sustava navedenog motora uz navedene glavne tehničke karakteristike motora. Za provedbu simulacija rada motora korišten je računalni program Engine Simulation britanske tvrtke Lotus Engineering. Usporedbom rezultata simulacije rada motora s vrijednostima snage i okretnog momenta stvarnog motora zaključilo se da je izrađeni model motora valjan te da vjerno opisuje rad stvarnog motora uz mala odstupanja vrijednosti dobivenih simulacijom od stvarnih vrijednosti motora. Također su se usporedili rezultati simulacije rada motora sa i bez hladnjaka stlačenog zraka.The thesis describes a zero-dimensional model of the turbocharged Waukesha H24GL gas engine. It also briefly describes the models used for engine simulation and the advantages and disadvantages of certain types of models. Mathematical models of each of the main parts of the engine that are interconnected into a single unit are described. The engine model is modelled after an industrial eight-cylinder in-line turbocharged gas engine. The formation of the fuel mixture in general as well as the ignition delay during combustion and the formation of the fuel mixture in Otto gas engines in particular are described. A description of the optimization of engine performance and the influence of variable valve opening and turbocharger performance optimization is given. A brief technical description of the main parts and systems of the analysed engine is given along with the main technical characteristics of the engine. The Engine Simulation computer program from the British company Lotus Engineering was used to perform simulations of engine operation. By comparing the results of the engine operation simulation with the power and torque values of the real engine, it was concluded that the created engine model is valid and satisfactorily describes the operation of the real engine with minor deviations of the values obtained by the simulation from the actual engine values. The results of the simulation of the engine operation with and without the intercooler were also compared

Analysis of gas engine characteristics for generator drive

U diplomskom radu opisan je nulto-dimenzionalni model plinskog motora Waukesha H24GL s prednabijanjem. Ukratko su opisani i simulacijski modeli motora, te prednosti i nedostaci pojedinih tipova modela. Opisani su matematički modeli svakog od glavnih dijelova motora koji su međusobno povezani u jednu cjelinu. Model motora je izrađen po uzoru na industrijski osamcilindrični, linijski plinski motor s prednabijanjem. Opisano je stvaranje gorive smjese, te problematika zakašnjenja paljenja pri izgaranju i posebno stvaranje gorive smjese kod Ottovih plinskih motora. Dan je opis optimizacije performansi motora te utjecaj varijabilnog otvaranja ventila te poboljšanje performansi turbopuhalom. Dan je sažeti tehnički opis glavnih dijelova i sustava navedenog motora uz navedene glavne tehničke karakteristike motora. Za provedbu simulacija rada motora korišten je računalni program Engine Simulation britanske tvrtke Lotus Engineering. Usporedbom rezultata simulacije rada motora s vrijednostima snage i okretnog momenta stvarnog motora zaključilo se da je izrađeni model motora valjan te da vjerno opisuje rad stvarnog motora uz mala odstupanja vrijednosti dobivenih simulacijom od stvarnih vrijednosti motora. Također su se usporedili rezultati simulacije rada motora sa i bez hladnjaka stlačenog zraka.The thesis describes a zero-dimensional model of the turbocharged Waukesha H24GL gas engine. It also briefly describes the models used for engine simulation and the advantages and disadvantages of certain types of models. Mathematical models of each of the main parts of the engine that are interconnected into a single unit are described. The engine model is modelled after an industrial eight-cylinder in-line turbocharged gas engine. The formation of the fuel mixture in general as well as the ignition delay during combustion and the formation of the fuel mixture in Otto gas engines in particular are described. A description of the optimization of engine performance and the influence of variable valve opening and turbocharger performance optimization is given. A brief technical description of the main parts and systems of the analysed engine is given along with the main technical characteristics of the engine. The Engine Simulation computer program from the British company Lotus Engineering was used to perform simulations of engine operation. By comparing the results of the engine operation simulation with the power and torque values of the real engine, it was concluded that the created engine model is valid and satisfactorily describes the operation of the real engine with minor deviations of the values obtained by the simulation from the actual engine values. The results of the simulation of the engine operation with and without the intercooler were also compared

Photochemical reactions in microreactors

Mikroreaktori su vrsta reaktora koja u posljednjih nekoliko godina doživljava veliku primjenu u kemijskoj procesnoj industriji i koju, za razliku od klasičnih reaktora, karakterizira red veličine od nekoliko mikrometara do nekoliko milimetara. Pored mikroreaktora, osim konvencionalnih mezo- i makroreaktora sve više se koriste nanoreaktori i milireaktori. Strukturna jedinica svakoga mikroreaktora su mikrokanali čija duljina može biti od nekoliko milimetara do nekoliko desetaka centimetara. Ove reaktorske sustave karakterizira dobar prijenos tvari i/ili topline, prvenstveno zbog velikog omjera između površine i volumena reaktora. Protok u takvim sustavima je većinom laminaran, a materijal od kojega su izrađeni obično ovisi o njihovoj primjeni. Jedna od glavnih prednosti provođenja eksperimenata u mikroreaktorskim sustavima je svakako sigurnost prilikom provođenja procesa jer takvi sustavi rijetko mogu dovesti do problema u radu, dok je njihov najveći nedostatak mali kapacitet, ali taj nedostatak se može prevladati serijskim ili paralelnim povezivanjem mikroreaktora. Posljednjih desetljeća heterogenim fotokemijskim reakcijama u mikroreaktorskim sustavima je posvećeno mnogo pažnje jer se pomoću čiste i dostupne energije sunčeve svjetlosti mogu pokretati reakcijski sustavi koji će proizvesti čistije i ekološki prihvatljivije produkte. Takve se reakcije obično provode u višefaznim reaktorima kako bi se dispergirao ili imobilizirao čvrsti fotokatalizator koji je u kontaktu s reaktantom. U takvim višefaznim mikroreaktorskim sustavima dolazi do jednostavnog i učinkovitog prijenosa kapljevine ili plina povezanog s kratkim difuzijskim putevima što je temelj provedbe kemijskih reakcija u protočnim sustavima.Microreactors are the type of reactors that have been greatly used in chemical process industry in last couple of years. As oppose to classical reactors they have sizes of a few millimeters to a few micrometers. Aside from microreactors there are also nanoreactors and millireactors. The structural unit of each microreactor are the microchannels whose dimensions are exceedingly small. These kind of reactor systems show the good properties of mass and/or heat transport, foremost because of a big ratio between surface and volume of reactors. The flow in these systems is mostly laminar, and the material of which they are made mostly depends on their use. One of the main advantages of doing experiments in microreactor systems is certainly the safety in running the process itself, because those kinds of process can rarely bring to problems in work, while their biggest disadvantage is their small capacity, but that disadvantage can be overcome by series or parallel connection of microreactors. In last couple of decades, a lot of attention is given to heterogeneous photochemical reactions in microreactor systems, because one can create purer and ecologically more acceptable products using only pure solar energy. Those kinds of reactions are done in multiphase reactors in order to disperse or immobilise solid photocatalyst that is in contact with reactant. In those multiphase microreactor systems, comes to a simple and effective transport of liquid and gas with short diffusion pathways, which becomes the foundation of reactions in flow systems

Photochemical reactions in microreactors

Mikroreaktori su vrsta reaktora koja u posljednjih nekoliko godina doživljava veliku primjenu u kemijskoj procesnoj industriji i koju, za razliku od klasičnih reaktora, karakterizira red veličine od nekoliko mikrometara do nekoliko milimetara. Pored mikroreaktora, osim konvencionalnih mezo- i makroreaktora sve više se koriste nanoreaktori i milireaktori. Strukturna jedinica svakoga mikroreaktora su mikrokanali čija duljina može biti od nekoliko milimetara do nekoliko desetaka centimetara. Ove reaktorske sustave karakterizira dobar prijenos tvari i/ili topline, prvenstveno zbog velikog omjera između površine i volumena reaktora. Protok u takvim sustavima je većinom laminaran, a materijal od kojega su izrađeni obično ovisi o njihovoj primjeni. Jedna od glavnih prednosti provođenja eksperimenata u mikroreaktorskim sustavima je svakako sigurnost prilikom provođenja procesa jer takvi sustavi rijetko mogu dovesti do problema u radu, dok je njihov najveći nedostatak mali kapacitet, ali taj nedostatak se može prevladati serijskim ili paralelnim povezivanjem mikroreaktora. Posljednjih desetljeća heterogenim fotokemijskim reakcijama u mikroreaktorskim sustavima je posvećeno mnogo pažnje jer se pomoću čiste i dostupne energije sunčeve svjetlosti mogu pokretati reakcijski sustavi koji će proizvesti čistije i ekološki prihvatljivije produkte. Takve se reakcije obično provode u višefaznim reaktorima kako bi se dispergirao ili imobilizirao čvrsti fotokatalizator koji je u kontaktu s reaktantom. U takvim višefaznim mikroreaktorskim sustavima dolazi do jednostavnog i učinkovitog prijenosa kapljevine ili plina povezanog s kratkim difuzijskim putevima što je temelj provedbe kemijskih reakcija u protočnim sustavima.Microreactors are the type of reactors that have been greatly used in chemical process industry in last couple of years. As oppose to classical reactors they have sizes of a few millimeters to a few micrometers. Aside from microreactors there are also nanoreactors and millireactors. The structural unit of each microreactor are the microchannels whose dimensions are exceedingly small. These kind of reactor systems show the good properties of mass and/or heat transport, foremost because of a big ratio between surface and volume of reactors. The flow in these systems is mostly laminar, and the material of which they are made mostly depends on their use. One of the main advantages of doing experiments in microreactor systems is certainly the safety in running the process itself, because those kinds of process can rarely bring to problems in work, while their biggest disadvantage is their small capacity, but that disadvantage can be overcome by series or parallel connection of microreactors. In last couple of decades, a lot of attention is given to heterogeneous photochemical reactions in microreactor systems, because one can create purer and ecologically more acceptable products using only pure solar energy. Those kinds of reactions are done in multiphase reactors in order to disperse or immobilise solid photocatalyst that is in contact with reactant. In those multiphase microreactor systems, comes to a simple and effective transport of liquid and gas with short diffusion pathways, which becomes the foundation of reactions in flow systems