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Long-term effects of volatilized methamphetamine on fruit fly locomotor activity
No full textKorištenje psihostimulansa poput metamfetamina dovodi do ovisnosti
te izaziva negativne posljedice za organizam. Uzastopnim korištenjem
opetovane doze psihostimulansa, povećava se lokomotorna aktivnost te
nastaje lokomotorna senzitizacija. Drosophila melanogaster je poznati
model za istraživanja ovisnosti i negativnih utjecaja psihostimulansa na
organizam. Psihostimulansi utječu na lokomotornu aktivnost i cirkadijalni
ritam vinskih mušica, a iznenadnim prekidom uzimanja psihostimulansa
nastaju simptomi apstinencije.
Cilj ovog istraživanja je bio ispitati postoje li dugotrajne posljedice na
aktivnost mušica tretiranih s dvije doze volatliziranog metamfetamina te
kako na to utječe osvjetljenje. Zanimala nas je razlika u lokomotornoj
aktivnosti između kontrola, mušica koje su razvile lokomotornu senzitizaciju
te onih koje nisu razvile lokomotornu senzitizaciju nakon administracije
dvije doza vMETH-a, tijekom uvjeta 12h svjetlo:12h i konstantnog mraka.
Dobiveni rezultati upućuju da pri pokusu provedenom u konstantnom
mraku, mušice koje su razvile LS maju veću aktivnost u usporedbi s
mušicama koje su čuvane u uvjetima 12h svjetlo:12h mrak, dok su mušice
koje nisu razvile lokomotornu senzatizaciju imale manju aktivnost u
usporedbi s kontrolnom skupinom i mušicama koje su razvile lokomotornu
senzitizaciju.
Potrebna su daljnja istraživanja kako bi se bolje razumijele dugotrajne
posljedice volatiliziranog metamfetamina na mušice, od kojih lokomotorna
aktivnost može biti jedan od markera apstinencijskih simptoma.The use of psychostimulants such as methamphetamine leads to
addiction and causes negative consequences for the organisms. With
repeated use of the same dose of psychostimulants, locomotor activity
increases and locomotor sensitization occurs. Drosophila melanogaster is a
well-known model for research on addiction and the negative effects of
psychostimulants on the body. Psychostimulants affect the locomotor
activity and circadian rhythm of fruit flies, and when psychostimulants are
stopped suddenly withdrawal symptoms occur.
This research aimed to examine whether there are long-term effects
on the activity of flies treated with two doses of volatility methamphetamine
and how lighting affect this. We were interested in the difference in
locomotor activity between controls, flies that developed locomotor
sensitization, and those that did not develop locomotor sensitization after
administration of two doses of vMETH, during 12h light: 12h dark and
continuous darkness conditions.
The obtained results indicate that in the experiment conducted in
constant darkness, flies that have develop LS have higher activity compared
to flies that were kept under conditions of 12h light:12h dark, while flies
that did not develop locomotor sensitization had lower activity compared to
the control group and flies that developed locomotor sensitization.
Further research is needed to better understand the long-term effects of
volatilized methamphetamine on flies, of which locomotor activity can be
one of the markers of withdrawal symptoms
Suspected adverse reactions to ATC J01 medicines group reported to HALMED
No full textBakterijske infekcije su zarazne bolesti nastale djelovanjem patogenih bakterija prisutnih u dovoljnom broju za nadjačavanje mehanizama obrane domaćina. Iako je razvijen velik broj antibiotika za liječenje bakterijskih infekcija, sve više bakterija rezistentno je na antibiotike, što zahtijeva razvoj novih metoda i principa liječenja istih. Izbor terapije ovisi o bakterijskom uzročniku i osobitostima pacijenta. Svrha ovog diplomskog rada je analiza prijava sumnji na nuspojave lijekova za liječenje bakterijskih infekcija za sustavnu primjenu (ATK J01) zaprimljenih u Hrvatsku agenciju za lijekove i medicinske proizvode (HALMED) u razdoblju od 1. listopada 2003. do 31. prosinca 2021. godine. Zaprimljeno je 4544 prijava koje su analizirane po godinama zaprimanja, dobi i spolu pacijenta, prijavitelju, ozbiljnosti, kriteriju ozbiljnosti, smrtnosti, sistematizaciji nuspojava prema klasifikaciji organskih sustava (SOC) Medicinskog rječnika za regulatorne poslove (MedDRA) te djelatnim tvarima skupine J01 koje su najčešće uzrokovale nuspojave i djelatnim tvarima koje su najčešće prijavljene uz djelatne tvari ATK skupine J01. Od ukupnog broja svih prijava sumnji na nuspojave lijekova u razdoblju od 2003. do 2021. godine, 8,5% su prijave sumnji na nuspojave lijekova skupine J01. Najveći broj prijava zabilježen je za pacijente ženskog spola (64,2%) i dobnu skupinu od 18 do 44 godina (29,7%). Najviše slučajeva prijavljeno je od strane liječnika (45,3%). Najveći broj prijavljenih slučajeva nije bio ozbiljan (67,1%). Najveći broj nuspojava pripada SOC Poremećaji kože i potkožnog tkiva (37,5%) i SOC Poremećaji probavnog sustava (37,3%), a najčešće nuspojave bile su proljev, pruritus/svrbež, osip i mučnina. Djelatne tvari koje su najčešće uzrokovale nuspojave su: kombinacija tvari amoksicilin trihidrat i kalijev klavulanat (18,7%), azitromicin (6,3%) i klaritromicin (5,7%). Djelatne tvari iz drugih ATK skupina koje su najčešće prijavljene uz djelatne tvari skupine J01 te koje su bile sumnjive, stupile u interakciju ili bile u istodobnoj terapiji s lijekovima skupine J01 su pantoprazol i bisoprolol. Analizirani podaci iz nacionalne baze nuspojava uspoređeni su s podacima iz europske i svjetske baze nuspojava lijekova i uočena je podudarnost podataka. HALMED-ov cilj jest unaprjeđenje i olakšavanje prijavljivanja sumnji na nuspojave lijekova te podizanje svijesti zdravstvenih djelatnika i pacijenata o važnosti istog.Bacterial infections are infectious diseases caused by the action of pathogenic bacteria present in sufficient numbers to overcome the defense mechanisms of the host. Although a large number of antibiotics have been developed to treat bacterial infections, more and more bacteria are resistant to antibiotics, which requires the development of new methods and principles for their treatment. The choice of therapy depends on the bacterial pathogen and the characteristics of the patient. The purpose of this thesis is to analyze the reports of suspected adverse reactions to antibacterials for systemic use (ATC J01) reported to the Agency for Medicinal Products and Medical Devices of Croatia (HALMED) in the period from October 1, 2003 to December 31, 2021. 4544 reports were received and analyzed by years of receipt, age and gender of a patient, reporter, seriousness, seriousness criteria, mortality, distribution to System Organ Class (SOC) of the Medical Dictionary for Regulatory Affairs (MedDRA) and J01 active substances, which most commonly caused adverse reactions, and active substances that were most commonly reported with the active substances of ATC J01 medicines group. In the total number of all reports of suspected adverse reactions to medicinal products in the period from 2003 to 2021, 8.5% were suspected adverse reactions reports for J01 medicines group. The highest number of reports was recorded for female patients (64.2%) and the age group from 18 to 44 years (29.7%). Most cases were reported by physicians (45.3%). The largest number of reported cases was not serious (67.1%). The largest number of adverse reactions belongs to SOC Skin and subcutaneous tissue disorders (37.5%) and SOC Digestive system disorders (37.3%), and the most common adverse reactions were diarrhea, pruritus/itching, rash and nausea. The active substances that most commonly caused adverse reactions were: a combination of amoxicillin trihydrate and potassium clavulanate (18.7%), azithromycin (6.3%) and clarithromycin (5.7%). Active substances from other ATC medicines groups that were most commonly reported with active substances from J01 medicines group and that were suspected, interacting or concomitant with J01 medicinal products were pantoprazole and bisoprolol. The analyzed data from the national database of adverse reactions were compared with the data from the European and global database of adverse reactions to medicinal products and the consistency of the data was observed. HALMED's goal is to improve and facilitate the reporting of suspected adverse reactions to medicinal products and to raise the awareness of healthcare professionals and patients about the importance of the same
Suspected adverse reactions to codeine-containing OTC medicines reported to HALMED
No full textBezreceptni se lijekovi s kodeinom koriste kod akutne boli, a djeluju na način da se kodein veže za opioidne receptore u centralnom živčanom sustavu i dovodi do smanjenja osjećaja boli te do umanjene reaktivnost na istu. Svrha ovog rada je analiza prijava sumnji na nuspojave bezreceptnih lijekova s kodeinom koje su zaprimljene od strane Hrvatske agencije za lijekove i medicinske proizvode (HALMED) u razdoblju od 2008. do 2021. godine. Analizirano je 60 prijava i 120 nuspojava, a rezultati su obrađeni prema: dobi i spolu pacijenta, prijavitelju, udjelu u ukupnim prijavama, ozbiljnosti, ishodu, povezanosti, vrsti nuspojava te prema pripadnosti nuspojava organskom sustavu klasificiranima od strane Medicinskog rječnika za regulatorne poslove (MedDRA). Također je provedena analiza konkomitanih i suspektnih djelatnih tvari. Najveći broj nuspojava prijavljeno je od strane liječnika, a najviše ih se odnosilo na osobe ženskog spola i dobnu skupinu od 18 do 44 godine. Najviše nuspojava bezreceptnih lijekova s kodeinom pripalo je organskim sustavima (SOC) Psihijatrijski poremećaji, SOC Poremećaji kože i potkožnog tkiva i SOC Gastrointestinalni poremećaji, a najčešće su nuspojave bile ovisnost o lijeku, svrbež, pospanost i pokušaj samoubojstva. Dobiveni podatci su uspoređeni s podatcima iz europske (EudraVigilance) i svjetske (VigiAccess) baze nuspojava te su zamijećena podudaranja u velikoj mjeri, ali ne u potpunosti. U nekim zemljama svijeta lijekovi s kodeinom su dostupni samo u receptnom statusu iz razloga što je jedna od njihovih najčešćih nuspojava ovisnost.Codeine-containing over-the-counter (OTC) medicines are most commonly used in treating acute pain and work by binding codeine to opioid receptors in the central nervous system than leading to a reduction in pain sensation and reduced reactivity to it. The purpose of this paper is to analyze reports of suspected adverse reactions of codeine-containing OTC medicines received by the Croatian Agency for Medicinal Products and Medical Devices (HALMED) in the period from 2008 to 2021. There were 60 reports and 120 adverse reactions analyzed, and the results were processed according to: age and sex of the patient, applicant, share in total reports, severity, outcome, association, type of adverse reaction and adverse reactions placed in different organic systems that were classified by the Medical Dictionary for Regulatory Affairs (MedDRA). An analysis of concomitant and suspected active substances was also performed. The largest number of adverse reactions were reported by physicians, most of them related to females and the age group of 18 to 44 years. Most adverse reactions of codeinecontaining OTC medicines belonged to the System organic class (SOC) Psychiatric disorders, SOC Skin and subcutaneous tissue disorders and SOC Gastrointestinal disorders. Most common side effects were drug
dependence, pruritus, somnolence and suicide attempt. The obtained data were compared with data from the European (EudraVigilance) and global (VigiAccess) database of adverse reactions, matches were observed to a large extent, but not completely. In some countries codeine-containing medicines are available only in prescription status because of its most
common adverse reaction; drug dependence
Neural stem cells
No full textNeuralne matične stanice generiraju neurone, astrocite i oligodendrocite u mozgu tijekom cijelog života. Najaktivnije su tijekom prenatalnog razvoja u procesu stvaranja živčanog sustava, dok u odrasloj dobi postoje u dvije regije mozga: subgranularnoj i subventrikularnoj. Matične stanice u subgranularnoj zoni nazivamo stanicama tipa 2, dok su to u subventrikularnoj zoni stanice tipa B. Asimetričnom diobom matičnih stanica nastaju progenitori; stanice tipa 1 u subgranularnoj i stanice tipa C u subventrikularnoj zoni. Neuroblasti nastaju diobom progenitora, a nazivamo ih stanicama tipa A, tj. stanicama tipa 3. Posljednji korak diferencijacije je stvaranje nezrelih neurona iz neuroblasta, nakon čega slijedi njihovo sazrijevanje i stvaranje sinapsi.
Otkriće neuralnih matičnih stanica omogućilo je značajan napredak u in vitro istraživanjima s obzirom da se neuroni, koji su post-mitotičke stanice vrlo teško kultiviraju. Kulture neuralnih matičnih stanica mogu se proizvesti na nekoliko načina iz embrionalnih matičnih stanica i induciranih pluripotentnih matičnih stanica. Rezultat kultivacije mogu biti 2D neuralne rozete i monokultura ili 3D neurosfere i organoidi.
Osim in vitro istraživanja, in vivo studije su dodatno razjasnile regulaciju matičnih stanica u neurogenim nišama u kojima se nalaze neuroni, glijalne i ependimalne stanice. Sve stanice prisutne u neurogenoj niši luče signalne molekule te tako utječu na održavanje, proliferaciju i diferencijaciju neuralnih matičnih stanica. Također, unutarnji regulatori poput transkripcijskih faktora, epigenetskih modifikacija i metaboličkih putova, potiču ili inhibiraju samoobnavljanje ili diferencijaciju.
Dosad je poznato samo nekoliko funkcija neurona nastalih u odrasloj dobi, ali poznato je da njihova ekscitabilnost i plastičnost omogućuju različite funkcije. Uključeni su u pamćenje i učenje, razlikovanje sličnih događaja i okruženja, kao i u odgovor na stres.
U liječenju neurodegenerativnih bolesti, ishemičnog moždanog udara i depresije također je prepoznata važnost neuralnih matičnih stanica. Neurodegenerativne bolesti i moždani udar su stanja u kojima dolazi do odumiranja neurona i propadanja tkiva te je transplantacija neuralnih matičnih stanica potencijalna terapija u njihovom liječenju. Do njihovog korištenja u terapijske svrhe moraju se otkriti preostale nepoznanice regulacije i funkcije adultne neurogeneze.Neural stem cells generate neurons, astrocytes and oligodendrocytes in the brain throughout life. They are most active during prenatal development in the process of formation of the nervous system, while in adulthood they exist in two regions: subgranular and subventricular zone. Stem cells in the subgranular zone are called type 2 cells, while in the subventricular zone they are called type B cells. The asymmetric division of stem cells creates progenitors; type 1 cells in the subgranular and type C cells in the subventricular zone. Neuroblasts are created by the division of progenitors, and we call them type A cells and type 3 cells, respectively. The last step of differentiation is the creation of immature neurons from neuroblasts, followed by their maturation and formation of synapses.
The discovery of neural stem cells enabled significant progress in in vitro research, given that neurons, which are post-mitotic cells, are very difficult to cultivate. Neural stem cell cultures can be produced in several ways from embryonic stem cells and induced pluripotent stem cells. The result of cultivation can be 2D neural rosettes and monoculture or 3D neurospheres and organoids.
In addition to in vitro research, in vivo studies have elucidated the regulation of stem cells in neurogenic niches where neurons, glial and ependymal cells reside. All cells present in the niche by secreting signaling molecules influence the maintenance, proliferation and differentiation of neural stem cells. Also, internal regulators such as transcription factors, epigenetic modifications and metabolic pathways promote or inhibit self-renewal or differentiation.
So far, only a few functions of adult-born neurons are known, but it is known that their excitability and plasticity enable distinct functions. They are involved in memory and learning, pattern separation as well as the stress response.
The importance of neural stem cells in the treatment of neurodegenerative diseases, ischemic stroke and depression was discovered. Neurodegenerative diseases and stroke are conditions in which neurons die and tissue decay, and neural stem cell transplantation is a potential therapy in their treatment. Until their use for therapeutic purposes, the remaining unknowns of the regulation and function of adult neurogenesis must be discovered
Technology transfer in biotechnology
No full textBiotehnologija je 1980-ih prepoznata i prihvaćena kao strateška tehnologija od strane većine industrijaliziranih zemalja, a do danas je dotakla ljudske živote u svim aspektima. Najveći utjecaj biotehnologije vidljiv je u zdravstvenom sektoru gdje se kontinuirano radi na istraživanju i razvoju novih lijekova i terapija. Biotehnologija se smatra važnim sredstvom stimuliranja gospodarstva na nacionalnoj i globalnoj razini i jednom od najbrže rastućih inovativnih industrija.
Transfer tehnologije u području biotehnologije je proces prijenosa znanstvenih otkrića, metoda, postupaka, tehnika i opreme iz jedne tvrtke, organizacije ili zemlje u drugu u svrhu daljnjeg razvoja i komercijalizacije.
Cilj rada je objasniti pojam i proces transfera tehnologije u biotehnologiji i odrediti čimbenike koji su ključni za uspješan proces. Kao potvrda teorijskom dijelu provedena je analiza trenutnog stanja u Europi i svijetu.
Iz provedenog istraživanja i analize rezultata može se zaključiti da su ulaganje u istraživanje i razvoj i patentna zaštita u području biotehnologije ključni za uspješan proces transfera tehnologije što rezultira gospodarskim rastom i povećanjem konkurentnosti država.In the 1980s biotechnology was recognized and accepted as a strategic technology by most industrialized countries, and up until today it has touched human lives in all aspects. The biggest impact of biotechnology is visible in the healthcare sector where there is continuous work on research and development of new medication and therapy. Biotechnology is considered an important means of stimulating the economy on a national and global scale and one of the fastest growing innovative industries.
Technology transfer in the field of biotechnology is a process of transferring scientific discoveries, methods, procedures, techniques and equipment from one company, organisation or country to another with the purpose of further development and commercialization.
The aim of the thesis is to explain the term and process of technology transfer in biotechnology and to determine the factors which are crucial for a successful process. As a confirmation to the theoretical part, an analysis of the current state in Europe and the world was conducted.
From the conducted research and the analysis of the results it can be concluded that the investment in research and development and patent protection in the field of biotechnology are key for a successful process of technology transfer which results in economic growth and the increase of competitiveness of countries
Analysis of sorting nexins in platelet transcriptome and proteome
No full textProteinska homeostaza stanice, poznata kao proteostaza, je stanje stanice u kojem proteom omogućava njeno pravilno funkcioniranje, a naposlijetku i njenu vijabilnost. Mnogobrojni procesi uključeni u održavanje navedenog stanja osiguravaju da proteini budu sintetizirani u odgovarajućim koncentracijama, smotani u valjanim konformacijama te pravilno locirani u stanici. Jedna od mnogobrojnih obitelji proteina uključena u procese održavanja proteinske homeostaze jest obitelj sortirajućih neksina (eng. sorting nexins, SNX). Ovu skupinu proteina karakterizira prisutnost phox domene koja veže fosfolipide (phox, PX domena). Interakcijom PX domene s fosfatidilinozitol 3-monofosfatom (PI3P) na membranama endocitnog sustava dolazi do pravovaljane lokalizacije SNX te koordinacije unutarstaničnog prometa proteina. Njihova uloga u endocitnom sustavu jest usmjeriti proteine na recikliranje i povratak na površinu stanice ili potaknuti njihovu degradaciju u lizosomima. Valja napomenuti kako pojedini članovi SNX obitelji uz PX domenu sadrže i druge domene koje doprinose sortiranju proteina. Prema tome koje funkcionalne domene sadrže, SNX se mogu podijeliti u sljedeće kategorije: SNX-PX, SNX-BAR, SNX-FERM, SNX-SH3, SNX-MIT, SNX-kinezin. Obzirom da su SNX uključeni u održavanje proteinske homeostaze ukoliko dođe do njihove disfunkcije posljedično dolazi do agregacije proteina ili do manjka istih što može dovesti do patoloških stanja.
U ovom radu napravljen je pregled SNX koji su prisutni u mišjim i ljudskim trombocitima korištenjem dostupnih transkriptomskih i proteomskih baza. Proučene su konzistentnosti između vrsta koje potencijalno mogu poslužiti za buduća istraživanja. Dodatno je analizirana uspješnost dobivanja staničnih linija te mišjih modela s delecijom odabranih SNX proteina izučavanjem dostupnih baza. Ovakav pregled omogućava bolje razumijevanje unutarstaničnog prometa proteina te uloge koju bi SNX mogli imati u nastanku ili funkciji trombocita.Protein homeostasis, also known as proteostasis, is the state of the cell where proteome enables normal cellular function and viability. Many processes, that are involved in maintaining this state, ensure that proteins are synthesized in right concentrations, folded in the right conformation and correctly localized in the cell. One of many protein families involved in processes that maintain protein homeostasis is the family of sorting nexins (SNX). This group of proteins is characterized by the presence of phospholipid binding domain (phox, PX domain). Association of the PX domain with phosphatidylinositol phosphate enriched membranes ensures the right subcellular localization of SNXs. Their role in the endocytic network is to direct protein recycling back to the cell membrane or to induce protein degradation in lysosomes. Thus, SNXs regulate intracellular cargo trafficking. Certain members of SNX family possess domains other that the PX domain. These domains are equally involved in the protein sorting process, and therefore SNX can further be divided into categories depending on the functional domains they possess: SNX-PX, SNX-BAR, SNX-FERM, SNX-SH3, SNX-MIT, SNX-kinesin.
In this thesis, an overview of the SNX proteins present in murine or human platelets was done using available transcriptomic and proteomic data bases. Consistencies in expression pattern among the species were examined, providing useful information for future research. In addition to that, available data on KO cell lines of highly expressed SNXs were examined to decipher which of SNX proteins is essential. This overview enables better understanding of intracellular protein trafficking and the potential role that SNXs could have in biogenesis or function of platelets
The effect of quercetin on the developmental consequences of methamphetamine in fruit fly
No full textMetamfetanim (METH) je psihostimulans koji dovodi do razvoja ovisnosti.
Naši preliminarni rezultati su pokazali da METH dovodi do promjena u broju
potomaka mužjaka vinske mušice. Razvojni ciklus je povezan s
metabolizmom, a time i sa razvojem reaktivnih oksidacijskih vrsta. METH
povećava stvaranje reaktivnih kisikovih vrsta (ROS) i ometa njihovo
uklanjanje, uzrokujući oksidativni stres. Kvercetin (QUE) je molekula s
poznatim antioksidativnim svojstvima koja bi potencijalno mogla djelovati
na promjene u razvojnom ciklusu uzrokovane METH-om.
Cilj eksperimentalnog rada je bio ispitati kako promjene u oksidacijskom
statusu (QUE) utječu na broj potomaka mužjaka izloženih vMETH-a. METH
je administriran grupi mužjaka pomoću FlyBong metode, nakon čega je
izdvojeno 20% mužjaka s najvećim lokomotornim odgovorom na METH.
Mužjaci su pareni sa netretiranim ženkama na hrani s različitim
koncentracijama QUE (0.6 mM i 3.2 mM). Praćen je utjecaj QUE na broj
potomaka tijekom tri generacije.
Rezultati su pokazali statistički značajno povećanje broja embrija prve
generacije u skupini koja je bila izložena METH-u kao i trend povećanog
broja čahura i mušica. Utjecaji METH-a se nije prenio na naredne
generacije, dok je utjecaj QUE-a bio vidljiv u drugoj, ali ne i trećoj
generaciji. Rezultati upućuju na potencijalan transgeneracijski utjecaj QUE
na redoks ravnotežu.
Kako bi se ovi rezultati statstički potvrdili, eksperiment je potrebno
ponoviti s povećanim brojem replika i poboljšanom formulacijom hrane.Methamphetamine (METH) is a psychostimulant that leads to the
development of addiction. Our preliminary results showed that METH leads
to changes in the number of male fruit fly offspring. The development cycle
is connected with metabolism, and thus with the development of reactive
oxidation species. METH increases the generation of reactive oxygen
species (ROS) and interferes with their removal, causing oxidative stress.
Quercetin (QUE) is a molecule with known antioxidant properties that could
potentially act on METH-induced changes in the developmental cycle.
The aim of the experimental work was to examine how changes in
oxidation status (QUE) affect the number of offspring of males exposed to
vMETH. METH was administered to a group of males using the FlyBong
method, after which 20% of males with the highest locomotor response to
METH were selected. Males were mated with untreated females on food
with different concentrations of QUE (0.6 mM and 3.2 mM). The influence
of QUE on the number of offspring was monitored over three generations.
The results showed a statistically significant increase in the number of
embryos of the first generation in the group that was exposed to METH, as
well as a trend of an increased number of cocoons and flies. The effects of
METH were not transmitted to subsequent generations, while the influence
of QUE was visible in the second but not the third generation. The results
suggest a potential transgenerational influence of QUE on redox balance.
In order to statistically confirm these results, the experiment needs to be
repeated with an increased number of replicates and an improved food
formulation
Encapsulation of laurel leaf phenolic extract (Laurus nobilis L.) using electrostatic extrusion : Master thesis
No full textSvrha ovog rada bila je inkapsulirati vodeni ekstrakt lovorovog lista (Laurus nobilis L.) tehnikom elektrostatske ekstruzije i odrediti udio ukupnih fenola, inkapsulacijski kapacitet, antioksidacijsku aktivnost i kinetiku otpuštanja fenolnih spojeva. Inkapsulacija se u prethodnim istraživanjima pokazala učinkovitim načinom zaštite i očuvanja stabilnosti fenolnih spojeva. Ispitivana je učinkovitost inkapsulacije pri različitim udjelima nosača: alginat (1, 1,5 i 2% w/v), kalcijev klorid (1,5, 3 i 5% w/v) sa i bez dodatka kitozana (0,5 %, w/v) u želirajućoj otopini. U dobivenim ekstraktima provedena je spektrofotometrijska analiza prema kojoj su rezultati pokazali kako dodatak kitozana u sastav želirajuće otopine pozitivno utječe na prinos ukupnih fenola i antioksidacijsku aktivnost, dok udio alginata nema značajan utjecaj. Udio ukupnih fenola određen je u rasponu od 9,21 - 20,38 mg GAE/g kapsula, s inkapsulacijskim kapacitetom u rasponu 44,56 - 98,30 %. Antioksidacijska aktivnost je izmjerena u rasponu od 7,14 – 20,18 μmol TAE/g kapsula. Prema statističkoj analizi rezultata definiran je optimalan udio nosača i sastav želirajuće otopine. Najveća koncentracija ukupnih fenola, inkapsulacijski kapacitet i antioksidacijska aktivnost su dobiveni u kapsulama s 2 % alginatom i s 1,5 % kalcijeva klorida s 0,5 % kitozana u želirajućoj otopini.The purpose of this study was to encapsulate an aqueous extract of bay leaf (Laurus nobilis L.) by electrostatic extrusion technique and to determine the yield of total phenols, encapsulation efficiency, antioxidant activity and release kinetics of phenolic compounds. Encapsulation was proven as an effective way to protect phenolic compounds and preserve their stability. The encapsulation efficiency was examined at different carrier proportions: alginate (1, 1,5 and 2% w/v), calcium chloride (1,5, 3 and 5% w/v) with and without the addition of chitosan (0,5% w/v) in a gelling solution. Spectrophotometric analysis was performed in the obtained extracts, and results showed that addition of chitosan in the gelling solution had a positive effect on the yield of total phenols and antioxidant activity, while the proportion of alginate had no significant effect. The proportion of total phenols was determined at a range of 9,21 - 20,38 mg GAE/g capsules, with an encapsulation efficiency range of 44,56 - 98,30%. Antioxidant activity was measured at a range of 7,14 – 20,18 μmol TAE/g capsules. Optimal carrier proportions were determined according to statistical analysis of the results. The highest concentration of total phenols, encapsulation efficiency and antioxidant activity were obtained in capsules with 2 % alginate and 1,5 % calcium chloride with 0,5 % chitosan in the gelling solution
Potencijalni pristupi koji mogu usporiti napredovanje Parkinsonove bolesti
No full textParkinson’s disease (PD) is the most common synucleinopathy and the second most common neurodegenerative disease worldwide. Its incidence usually increases with age and, due to extended lifespan and increased share of older population, it is estimated that almost 13 million people in the world will suffer from PD by 2040. These facts lead to a concern and need to find effective drugs that potentially cure the disease. PD is defined as progressive disorder in which comes to degeneration of dopaminergic neurons in substantia nigra pars compacta (SNpc) and afterwards is widespread in all parts of the brain. This neurodegeneration is recognized by stiffness, tremor and bradykinesia, but also by cognitive symptoms such as dementia, autonomic dysfunction, mood and sleep disorders. The biggest problem is that developing PD is not an outcome of a single factor. As for now, PD-linked missense mutations are identified on at least 20 genes. With genetic modifications, there are also environmental factors that were correlated with either increasing or decreasing the risk of PD. As synucleinopathy, PD is mainly characterised by the aggregation of α-synuclein (α-syn) that forms Lewy bodies (LB) and Lewy neurites (LN). Since it is localized in presynaptic terminals, it has been suggested that α-syn has a major role in regulating synaptic vesicle release. However, under pathophysiological conditions, it starts to aggregate into neurotoxic oligomers and fibrils that disrupt many functions on extracellular and intracellular level. Current therapy does not have possibility to modify the disease, but it manages symptoms and improves patient’s quality of life. Levodopa is the most prescribed drug for PD patients because it converts to dopamine and increases its uptake. However, when its concentration in the plasma decreases, patient experiences a phenomenon called “wearing-off”. Thereby, alternatives such as dopamine agonists, monoamine oxidase B (MAO-B) and catechol-O-methyltransferase (COMT) inhibitors were introduced to the market, but none of them showed better performance than levodopa. There are also surgical procedures which improve levodopa phenomenon, although there is a greater risk of adverse side effects, complications during the procedure or even death. However, deep brain stimulation (DBS) proved to be successful in improving motor functions without severe outcomes and there is a great potential that in future it will be used for decreasing neurodegeneration. With DBS, there are several approaches that are currently in clinical trials and hopefully they will be introduced as disease-modifying treatment in the future.Parkinsonova bolest (PB) je najčešća sinukleinopatija te druga najčešća neurodegenerativna bolest u svijetu. Njena učestalost obično raste sa starošću te se, zbog produljenog životnog vijeka i povećanog udjela starijeg stanovništva, procjenjuje da će gotovo 13 milijuna ljudi bolovati od PB do 2040. godine. Ovakvi podaci izazivaju zabrinutost i potrebu za pronalaskom učinkovitih lijekova koji će potencijalno liječiti bolest. PB se definira kao progresivni poremećaj u kojem dolazi do degeneracije dopaminergičnih neurona u substantia nigra pars compacta (SNpc), a zatim se proširuje u sve dijelove mozga. Prepoznaje se po ukočenosti, tremoru i bradikineziji, ali i po kognitivnim promjenama poput demencije, autonomne disfunkcije, poremećaja raspoloženja i spavanja. Najveći problem je što razvoj PB nije posljedica samo jednog čimbenika. Zasada su missense mutacije koje su povezane uz PB identificirane na najmanje 20 gena. Uz genetske modifikacije, postoje i okolišni čimbenici koji mogu povećati ili smanjiti rizik obolijevanja. Kao sinukleinopatija, PB je uglavnom karakterizirana nakupljanjem α-sinukleina (α-syn) koje tvori Lewyjeva tjelešca (LB) i Lewyjeve neurite (LN). Budući da je lokaliziran na krajevima presinaptičkih neurona, pretpostavlja se da α-syn ima važnu ulogu u regulaciji otpuštanja sinaptičkih vezikula. Međutim, pod patofiziološkim uvjetima, počinje se nakupljati u neurotoksične oligomere i fibrile koji narušavaju brojne funkcije na izvanstaničnoj i unutarstaničnoj razini. Trenutna terapija nema mogućnost ublažavanja bolesti, ali kontrolira simptome i poboljšava kvalitetu života pacijenta. Levodopa je lijek koji se najčešće propisuje PB pacijentima jer se pretvara u dopamin i povećava njegovu razinu u mozgu. Međutim, kada se koncentracija novonastalog dopamina u plazmi ponovno smanji, pacijent doživljava fenomen koji se naziva engl. “wearing-off”. Time su na tržištu uvedene druge opcije poput agonista dopamina, inhibitora monoamino oksidaze B i katehol-O-metiltransferaze, ali nijedan od njih ne pokazuje bolje rezultate od levodope. Postoje i kirurški zahvati koji ublažavaju fenomen levodope, iako postoji veći rizik od neželjenih nuspojava, komplikacija tijekom zahvata, pa čak i smrti. Međutim, duboka mozgovna stimulacija (DMS) se pokazala uspješnom u poboljšanju motoričkih funkcija bez težih ishoda i postoji veliki potencijal da će se u budućnosti koristiti za smanjenje neurodegeneracije. Uz DMS, postoji nekoliko pristupa koji su trenutno u kliničkim ispitivanjima i nadamo se da će biti uvedeni kao terapija koja liječi PB u budućnosti
Istraživanje potencijalnih patogenih mehanizama Alzheimerove bolesti preko analize gama sekretaze
No full textBackground: Alzheimer`s disease (AD) is a progressive neurologic disorder that causes brain atrophy and neuronal cell death which in turn manifests as dementia. In later stages of the disease patients are unable to care for themselves. This alongside the high number of people affected, makes AD the most expensive condition for health care providers in the industrialized nations. The pathogenic processes underlining AD usually occur through dysregulation of amyloid-β (Aβ) processing. The transmembrane protease responsible for Aβ cleavage is Gamma-secretase. All current attempts to cure AD trough regulation of γ-secretase have resulted in little to no observed effect on the pathogenesis of the disease. This miss in drug creation is caused by a lack of information regarding understanding Aβ formation. Better knowledge of the factors involved in Aβ processing is needed.
Experimental: Gamma-secretase structures at 3.4 angstrom resolution were analyzed using multiscale molecular dynamic approaches and electrostatic calculations.
Results: Multiscale molecular dynamics can describe structural interactions that occur in the binding of C99-CTFβ to the γ-secretase complex. C99-CTFβ is capable of docking near the active site disrupting substrate processing. Such interactions can partially or fully inhibit gamma-secretase or shift the proteolytic cleavages from the Aβ 40 path to the neurotoxic Aβ 42. Nicastrine can exist in an open or a closed form. The closed form prevents substrates from interacting, preventing the disruption of the active site.
Conclusion: Through substrate oversaturation, interactions can lead to a change in the mechanism and precision of Aβ cleavage. This can drive pathogenic processes in AD.Pozadina: Alzheimerova bolest (AD) je progresivni neurološki poremećaj koji uzrokuje atrofiju mozga i smrt neuronskih stanica što se zauzvrat očituje kao demencija. U kasnijim fazama bolesti, pacijenti nisu u stanju brinuti sami za sebe. To zajedno s velikim brojem pogođenih ljudi, čini AD najskupljom bolesti za zdravstveni sektor u industrijaliziranim zemljama. Patogeni procesi koji dovode do bolesti obično se postižu poremećajem u regulaciji procesiranja amiloidnog proteina (Aβ). Transmembranska proteaza zaslužna za sječenje amiloida je γ-sekretaza. Svi pokušaji izlječenja AD preko regulacije γ-sekretaze su završili bezuspješno. Vjerojatni razlog tome je manjak razumijevanja mehanizma procesiranja amiloidnog proteina. Potrebni je više znanja o faktorima koji su uključeni u taj proces.
Eksperimentalno: Strukture gama-sekretaze, s razlučivošću od 3,4 Å, analizirane su korištenjem različitih molekularno-dinamičkih pristupa i elektrostatskih proračuna.
Rezultati: Molekularna dinamika može opisati strukturne interakcije koje se javljaju vezanjem C99-CTFβ na kompleks gama-sekretaze. C99-CTFβ se može dokirati u blizini aktivnog mjesta i time ometat procesiranje supstrata. Takve interakcije mogu djelomično inhibirati gama-sekretazu ili preusmjeriti proteolitičko cijepanje s Aβ 40 fragmenta na neurotoksični Aβ 42. Nikastrin može postojati u otvorenom ili zatvorenom obliku. Zatvoreni oblik onemogućava interakcije sa supstratom i time sprečava disrupciju aktivnog mjesta.
Zaključak: Preko zasićenja supstratom, moguće je dovesti do promjene u procesiranju amiloidnog proteina. Takve promjene mogu potaknuti nastanak Alzheimerove bolesti