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Usporedba analitičkih značajki hematoloških analizatora s peterodijelnom diferencijalnom krvnom slikom
No full textCilj istraživanja
Cilj rada je prikazati verifikacije analitičkih značajki različitih hematoloških analizatora s
peterodijelnom diferencijalnom krvnom slikom (Siemens Advia 2120i, Sysmex XN-1000,
Mindray BC-5310, Beckman Coulter DxH 900) te kritički usporediti njihove značajke po
segmentima verifikacijskog protokola.
Materijali i metode
Ispitivani su parametri kompletne krvne slike s diferencijalnom krvnom slikom.
Verifikacijski protokol obuhvaća: procjenu preciznosti, točnosti, provjeru linearnosti
mjerenja, verifikaciju i određivanje granica slijepe probe (LoB), granica detekcije (LoD) i
granica kvantifikacije (LoQ) analita te procjenu utjecaja mogućeg prijenosa uzorka nakon
analize (engl. carryover). Za statističku obradu podataka korišten je statistički program
MedCalc 12.6.2.0 (Ostend, Belgija) i Microsoft Office Excel. Kriteriji prihvatljivosti su
definirani na temelju suvremenih literaturnih podataka, kriterija proizvođača i biološke
varijabilnosti.
Rezultati
Verifikacijom ponovljivosti i preciznosti mjerenja dokazana je raznolikost rezultata koja
upućuje na različite značajke analizatora. Prihvatljivost dobivenih rezultata uvelike ovisi o
definiranim kriterijima prihvatljivosti. Ispitivanje točnosti mjerenja usporedbom s definiranim
referentnim analizatorom (Siemens Advia 2120i) pokazalo je višestruke statistički značajne
razlike. Uspješno su verificirani i određeni LoB, LoD i LoQ analita. Nezadovoljavajući LoQ
je za trombocite kod Sysmex XN-1000 što je vjerojatno rezultat nepostignutog uzorka
niskog broja trombocita. Ispitivane linearnosti mjernog raspona ne zadovoljaju kriterije za
eritrocite i hemoglobin na Mindray BC-5310CRP. Ispitivanjem carryover-a zadovoljeni su
svi kriteriji, osim za hemoglobin određen Siemens Advia 2120i, pri čemu je zadovoljen
postavljen kriterij proizvođača (≤1) ali ne i literaturni kriterij (<0,4).
Zaključak
Analitičke značajke analizatora opisane proizvođačevom validacijom nije moguće u
potpunosti zadovoljiti u rutinskom laboratorijskom radu. Prilikom korisničke verifikacije
potrebna je svjesnost ograničenja i razlika među platformama različitih proizvođača.Objectives
The paper aims to present verifications of the analytical features of various 5-part
differential hematology analyzers (Siemens Advia 2120i, Sysmex XN-1000, Mindray BC5310, Beckman Coulter DxH 900) and to critically compare their performance by
verification protocol segments.
Materials and Methods
The complete blood count parameters with the differential blood count were examined.
The verification protocol includes assessment of precision, accuracy, linearity, verification
and determination of limits of blank (LoB), detection (LoD) and quantification (LoQ) and
carryover. The obtained results will be statistically processed using the statistical program
MedCalc 12.6.2.0 (Ostend, Belgium) and Microsoft Office Excel. Acceptability criteria are
defined based on up-to-date literature data, manufacturer's criteria and biological
variability.
Results
The variety of repeatability and precision results were proven, leading to different
performance of the analyzers. The acceptability largely depends on the defined acceptance
criteria. The accuracy was determined by comparing it with a defined reference analyzer
(Siemens Advia 2120i), which showed multiple statistically significant differences. The
LoB, LoD and LoQ were successfully verified and determined, except for platelets LoQ on
Sysmex XN-1000, which is likely the result of an unreachable low platelet count. Measuring
range linearity does not meet criteria for erythrocytes and hemoglobin on Mindray BC5310CRP. The carryover tests met the requirements except for hemoglobin by Siemens
Advia 2120i, where the manufacturer's criterion (≤1) was met, but not the literature one
(<0.4).
Conclusion
Analytical features declared by manufacturer's validation are difficult to achieve in
routine laboratory conditions. During user verification, it is necessary to be aware of the
limitations and differences between analyzers from different manufacturers
Synthesis and mechanisms of solvolysis of benzyl-bromides in 80% methanol
No full textTema ovog rada je proučavanje sinteze i mehanizma solvolize različito supstituiranih benzilnih
bromida u 80 %-tnom metanolu. U tu svrhu sintetizirani su 4-metoksibenzil-bromid uz pomoć acetilbromida, a 4-(metiltio)benzil-bromid, 4-fenoksibenzil-bromid, 3,4-dimetilbenzil-bromid, 4-
metilbenzil-bromid, 4-tert-butilbenzil-bromid, 4-fenilbenzil-bromid i 3,5-dimetilbenzil-bromid uz
pomoć fosforovog tribromida. Čistoća ovih spojeva utvrđena je tankoslojnom tekućinskom
kromatografijom (TLC) i nuklearnom magnetskom rezonancijom (NMR).
Konstante brzine solvolize navedenih benzil-bromida utvrđene su konduktometrijski u 80 %-
tnom metanolu pri 25 °C. Spoj 3,5-dimetilbenzil-bromid sporije je solvolizirao pri 25 °C, pa su
njegove konstante brzine solvolize utvrđene pri višim temperaturama i potom ekstrapolirane na 25
°C pomoću Eyringove jednadžbe. Napravljena je korelacijska analiza logaritama konstanti brzine
solvolize i σ + - vrijednosti odgovarajućih supstituenata kako bi dobili Hammett-Brownov graf.
Rezultat su dva pravca različitih nagiba, pri čemu je prvi definiran točkama koje pripadaju 4-
metoksibenzil-bromidu, 4-(metiltio)benzil-bromidu i 4-fenoksibenzil-bromidu. Drugi graf definiran
je točkama koje pripadaju 3,4-dimetilbenzil-bromidu, 4-metilbenzil-bromidu, 4-tert-butilbenzilbromidu, 4-fenilbenzil-bromidu i 3,5-dimetilbenzil-bromidu. Nagibi pravaca označuju iznos reakcijske konstante ρ + koja nam govori o promjeni naboja na reakcijskom centru. U slučaju strmijeg pravca visoka negativna vrijednost reakcijske konstante (ρ + = -6,79) sugerira na nastanak stabilnog
karbokationa koji je karakterističan za SN1 reakciju. Manje strmi pravac ima vrijednost reakcijske
konstante ρ + = - 2,49, što sugerira na SN2 mehanizam reakcije.
Eksperimentom je dokazano da spojevi 4-metoksibenzil-bromid, 4-(metiltio)benzil-bromid i
4-fenoksibenzil-bromid solvoliziraju SN1 mehanizmom, a 3,4-dimetilbenzil-bromid, 4-metilbenzilbromid, 4-tert-butilbenzil-bromid, 4-fenilbenzil-bromid i 3,5-dimetilbenzil-bromid solvoliziraju
SN2 mehanizmom.The topic of this thesis is the study of the synthesis and solvolysis mechanisms of variously
substituted benzyl bromides in 80 % methanol. For this purpose, 4-methoxybenzyl bromide was
synthesized using acetyl bromide, while 4-(methylthio)benzyl bromide, 4-phenoxybenzyl bromide,
3,4-dimethylbenzyl bromide, 4-methylbenzyl bromide, 4-tert-butylbenzyl bromide, 4-phenylbenzyl
bromide, and 3,5-dimethylbenzyl bromide were synthesized using phosphorus tribromide. The
purity of these compounds was confirmed using thin-layer chromatography (TLC) and nuclear
magnetic resonance (NMR).
The rate constants of solvolysis for the benzyl bromides were determined conductometrically
in 80 % methanol at 25 °C. The solvolysis of 3,5-dimethylbenzyl bromide was slower at 25 °C, so
its rate constants were measured at higher temperatures and then extrapolated to 25 °C using the
Eyring equation. A correlation analysis of the solvolysis rate constants and σ+ values of the
corresponding substituents was conducted to create a Hammett-Brown plot. The result is two lines
with different slopes: one defined by 4-methoxybenzyl bromide, 4-(methylthio)benzyl bromide, and
4-phenoxybenzyl bromide, and the other by 3,4-dimethylbenzyl bromide, 4-methylbenzyl bromide,
4-tert-butylbenzyl bromide, 4-phenylbenzyl bromide, and 3,5-dimethylbenzyl bromide. The slopes
indicate the reaction constant ρ+, which provides insight into the change in charge at the reaction
center. The steeper line, with a highly negative ρ+ value (-6.79), suggests the formation of a stable
carbocation typical of an SN1 reaction, while the less steep line, with ρ+ = -2.49, points to an SN2
mechanism.
The experiment confirmed that 4-methoxybenzyl bromide, 4-(methylthio)benzyl bromide,
and 4-phenoxybenzyl bromide undergo solvolysis via the SN1 mechanism, whereas 3,4-
dimethylbenzyl bromide, 4-methylbenzyl bromide, 4-tert-butylbenzyl bromide, 4-phenylbenzyl
bromide, and 3,5-dimethylbenzyl bromide undergo solvolysis via the SN2 mechanism
Adherence of patients with asthma and COPD to inhalation therapy and influencing factors
No full textKronične bolesti su stanja koja prate pacijente tijekom cijelog života i obično se ne mogu potpuno izliječiti. Kod
kroničnih respiratornih bolesti poput KOPB-a i astme, redovita primjena inhalatorne terapije izuzetno je važna kako bi
se smanjila učestalost akutnih pogoršanja i smanjilo opterećenje zdravstvenog sustava. Stoga, pridržavanje terapije jedan
je od ključnih faktora u liječenju kroničnih bolesti. U istraživanju su sudjelovali pacijenti koji boluju od astme ili KOPBa i koriste minimalno jedan inhalator u terapiji. Istraživanje je provedeno na području Slavonije i Dalmacije, a uključivalo
je 100 ispitanika. Veći broj ispitanika boluje od astme (71%), a najčešće korišten inhalator je MDI - inhalatori aerosola
(40%). Rezultati istraživanja pokazuju da je najveći broj pacijenata djelomično adherentan (37%), dok je najmanji broj
pacijenata adherentan (29%). Parametri koji su statistički značajno utjecali na razinu pridržavanja su zaposlenost
(p=0,001) i dob (p=0,016). Nezaposleni pacijenti i stariji pacijenti pokazali su veću razinu adherencije. Također,
istraživanje je otkrilo da većina pacijenata (99%) poznaje svoj terapijski režim, dok manji broj pacijenata (35%) čini
kritične pogreške prilikom inhalacije lijeka. Personalizirani pristupi liječenju, edukacija pacijenata i provjera inhalacijske
tehnike od strane farmaceuta ključni su za poboljšanje adherencije.Chronic diseases are lifelong conditions that usually cannot be completely cured. In chronic respiratory diseases such as COPD and asthma, regular use of inhalation therapy is crucial to reduce the frequency of acute exacerbations and alleviate the burden on the healthcare system. Thus, adherence to therapy is a key factor in the treatment of chronic diseases. This study involved patients with asthma or COPD who use at least one inhaler in their therapy. Conducted in the regions of Slavonia and Dalmatia, the research included 100 participants. A larger proportion of participants had asthma (71%), and the most commonly used type of inhaler was the MDI aerosol inhaler (40%). The study results showed that the majority of patients were partially adherent (37%), while the smallest proportion could be considered fully adherent (29%). Employment status (p=0.001) and age (p=0.016) were the parameters that significantly influenced the level of adherence to inhalation therapy. Unemployed and older patients showed a higher level of adherence. Additionally, the study revealed that most patients (99%) knew their therapeutic regimen, while a smaller number of patients (35%) made critical errors during inhalation. Personalized treatment approaches, patient education, and pharmacist-led inhalation technique checks are crucial for improving adherence
Application of the Sysmex XN-3100 hematology analyzer in detecting presence of schistocytes in the peripheral blood of patients suspected of thrombotic microangiopathy
No full textBrojenje shistocita ima ključnu dijagnostičku vrijednost u dijagnostici trombotskih mikroangiopatija. Svjetlosna mikroskopija je kao referentna metoda subjektivna, ručna, vremenski zahtjevna, ovisna o stručnosti osoblja i podložna brojnim varijabilnostima. Cilj ovog istraživanja bio je ispitati mogućnosti hematološkog analitičkog sustava Sysmex XN-3100 u brojenju shistocita i usporediti dobivene rezultate s rezultatima svjetlosne mikroskopije (SHISTO-SM). Ispitan je parametar broj fragmentiranih eritrocita (FRC) na hematološkom analizatoru Sysmey XN-1000, te je osmišljena i dizajnirana metoda za analizu shistocita na digitalnom analizatoru morfologije Sysmex DI-60 (SHISTO-DI). Za brojenje FRC-a analizator primjenjuje metodu fluorescentne protočne citometrije u retikulocitnom kanalu koja FRC detektira kao signal niske fluorescencije u specifičnom području ispod eritrocita. Vrijednosti FRC>0,5% smatrane su pozitivnima. Na uređaju DI-60 izbrojeni su shistociti na pretraživanom dijelu razmaza od 8,5 velikih vidnih polja (HPF) te je izračunat broj shistocita po jednom HPF-u. Vrijednosti shistocita >2/HPF smatrane su pozitivnima. Od ukupno 92 uzorka, svim trima metodama je dobiveno 51 podudarnih i 41 nepodudarnih rezultata. Najviše nepodudarnih rezultata nađeno je u skupini s pozitivnim FRC-om i negativnim rezultatima SHISTO-DI i SHISTO-SM. U odnosu na SHISTO-SM, za SHISTO-DI je dobivena osjetljivost 93,3%, specifičnost 83,1%, pozitivna prediktivna vrijednost (PPV) 51,9% i negativna prediktivna vrijednost (NPV) 98,5%, dok je za FRC dobivena osjetljivost 86,7%, specifičnost 62,3%, PPV 30,9% i NPV 96,0%. Najbolja korelacija (ρ=0,593) i podudarnost (κ=0,54) postignuta je između SHISTO-DI i SHISTO-SM, dok je slaganje SHISTO-DI i SHISTO-SM s metodom brojenja FRC-a slabije. FRC kao probirni parametar pokazuje visoku osjetljivost u otkrivanju prisutnosti shistocita, ali je svaki pozitivan nalaz potrebno potvrditi svjetlosnom mikroskopijom. Metoda SHISTO-DI pokazuje dobro slaganje s referentnom metodom, što naglašava njen doprinos budući da je automatizirana, brža, jednostavnija i reproducibilnija od ručne metode.Schistocyte count has a crucial diagnostic value in the diagnosis of thrombotic microangiopathies. Light microscopy, as the reference method, is subjective, manual, time-consuming, dependent on staff expertise and susceptible to various variabilities. This study aimed to evaluate the capabilities of the hematological analytical system Sysmex XN-3100 in counting schistocytes and to compare the obtained results with those of light microscopy (SHISTO-SM). The parameter fragmented red blood cells (FRC) was examined on a hematological analyzer Sysmex XN-1000. For FRC count, analyzer applies the method of fluorescent flow cytometry in the reticulocyte channel, detecting FRC as a low-fluorescence signal in a specific area below the red blood cells. FRC values >0.5% were considered positive. Besides, a method for schistocyte analysis using the digital morphology analyzer Sysmex DI-60 (SHISTO-DI) was designed and developed. Schistocytes were counted on the DI-60 device, in a scanned smear area of 8.5 high-power fields (HPF), and the number of schistocytes per HPF was calculated. Schistocyte values >2/HPF were considered positive. Out of a total of 92 analyzed samples, 51 matching and 41 non-matching results were obtained across the three methods. The highest number of non-matching results was found in the group with a positive FRC result and both negative SHISTO-DI and SHISTO-SM results. Compared to SHISTO-SM, SHISTO-DI demonstrated a sensitivity of 93.3%, specificity of 83.1%, positive predictive value (PPV) of 51.9%, and negative predictive value (NPV) of 98.5%. For FRC, the sensitivity was 86.7%, specificity 62.3%, PPV 30.9%, and NPV 96.0%. The best correlation (ρ=0.593) and agreement (κ=0.54) were achieved between SHISTO-DI and SHISTO-SM, while the concordance of both SHISTO-DI and SHISTO-SM with the FRC counting method was poor. FRC, as a screening parameter, shows high sensitivity in schistocyte identification, but every positive finding requires confirmation by light microscopy. The SHISTO-DI method shows good agreement with the reference method, emphasizing its contribution as an automated, faster, simpler, and more reproducible method compared to the manual method
Pharmacotherapeutic approaches in the treatment of premenstrual dysphoric disorder
No full textPredmenstrualni disforični poremećaj (PMDD) najteži je oblik predmenstrualnog sindroma, koji pogađa velik broj
žena i značajno narušava kvalitetu njihova svakodnevnog života. Unatoč izraženim fizičkim i emocionalnim
simptomima, poremećaj često ostaje nedijagnosticiran, što dovodi do toga da mnoge pacijentice ostaju uskarećene za
odgovarajuću terapijsku podršku. Simptomi poput razdražljivosti, anksioznosti, depresivnog raspoloženja, kroničnog
umora, poremećaja spavanja te bolova u tijelu javljaju se u lutealnoj fazi menstrualnog ciklusa i tipično nestaju s
početkom menstruacije. Iako patofiziološki mehanizmi PMDD-a još uvijek nisu u potpunosti razjašnjeni, smatra se da
ključnu ulogu imaju hormonalne fluktuacije i njihova interakcija s neurotransmiterskim sustavima.
U liječenju PMDD-a najčešće se primjenjuju selektivni inhibitori ponovne pohrane serotonina (SSRI), koji pravilnim
doziranjem postižu dobru učinkovitost uz relativno blage nuspojave. Kao sljedeće terapijske linije koriste se
kombinirani hormonski kontraceptivi i GnRH agonisti koje prati veći rizik od nuspojava, osobito pri dugotrajnoj
primjeni. Ostale terapijske opcije, poput NSAID, anksiolitika i diuretika, mogu pomoći kod pojedinih simptoma, ali
zbog nuspojava također zahtijevaju opreznu primjenu. Među novijim terapijama, sepranolon se ističe kao obećavajući
lijek s povoljnim omjerom učinkovitosti i nuspojava.
Veoma važnu ulogu imaju i nefarmakološke mjere: uravnotežena prehrana, tjelovježba i kognitivno-bihevioralna
terapija, a od dodataka prehrani se učinkovitošću ističu ekstrakt ploda konopljike, kalcij, vitamin B6 i magnezij. S
obzirom na širok raspon dostupnih lijekova i OTC pripravaka, savjetovanje s ljekarnikom ključno je za pravovremeno
prepoznavanje simptoma, edukaciju pacijentica i praćenje terapijske adherencije.Premenstrual Dysphoric Disorder (PMDD) is the most severe form of premenstrual syndrome, affecting a
significant number of women and considerably impairing their daily quality of life. Despite pronounced physical
and emotional symptoms, the disorder often remains undiagnosed, leaving many patients without appropriate
therapeutic support. Symptoms such as irritability, anxiety, depressed mood, chronic fatigue, sleep disturbances,
and bodily pain typically occur during the luteal phase of the menstrual cycle and subside with the onset of
menstruation. Although the pathophysiological mechanisms of PMDD are not yet fully understood, hormonal
fluctuations and their interaction with neurotransmitter systems are believed to play a key role.
The most commonly used treatment for PMDD involves selective serotonin reuptake inhibitors (SSRIs), which,
with proper dosing, offer good efficacy and relatively mild side effects. As second-line therapies, combined
hormonal contraceptives and GnRH agonists are used, though they carry a higher risk of adverse effects,
especially with long-term use. Other treatment options, such as NSAIDs, anxiolytics, and diuretics, may help
manage specific symptoms but also require cautious administration due to potential side effects. Among newer
therapies, sepranolone has emerged as a promising agent, showing a favorable balance between efficacy and
tolerability.
Non-pharmacological measures also play an important role, including a balanced diet, regular physical activity,
and cognitive-behavioral therapy. Certain dietary supplements, such as chasteberry extract, calcium, vitamin B6,
and magnesium, have demonstrated effectiveness. Given the wide range of available medications and over-thecounter
products, pharmacist consultation is essential for timely symptom recognition, patient education, and
adherence monitoring
Mehanizmi antitumorskog djelovanja vitamina A, D, E i C
No full textMalignant diseases are one of the leading global causes of morbidity and mortality despite progress in their diagnoses and treatments. Therefore, the importance of preventive action is emphasized, which
includes the chemoprotective effect of adequate nutrition. Vitamins A, D, E and
C have been proven as the most effective in the prevention of cancer due to their
numerous mechanisms of antitumor action. Provitamin A (P-carotene), as well
as vitamins E and C have an important chemoprotective role in suppressing oxidative stress as one of the triggers of carcinogenesis. Vitamins A and D exert
their antitumor effect primarily by affecting the gene expression, which leads to
the inhibition of tumor cell proliferation, metastasis and angiogenesis, as well as
stimulation of apoptosis of tumor cells. The stated vitamins are also necessary
for the normal functioning of the immune system which participates in the prevention and suppression of carcinogenesis. These vitamins are effective as adjuvant therapy in combined chemotherapy. Despite numerous in vitro studies describing different molecular mechanisms of antitumor effects of vitamins, new
mechanisms are still being discovered but more extensive clinical studies are
needed to determine their optimal status in order to ensure their antitumor
potential
Development and validation of a stability-indicating method for etrasimod using high-perhormance liquid chromatography
No full textUpalna bolest crijeva (eng. Inflammatory bowel disease, IBD) nepredvidiva je kronična bolest čija
je incidencija u stalnom porastu Prema lokali aciji patoloških promjena i ra ličitoj ahvaćenosti
stjenke probavnog sustava ra likujemo ulcero ni kolitis i Chronovu bolest Na tržištu se nala e se
brojni odobreni lijekovi a liječenje navedenih stanja, ali mnogi pacijenti ne reagiraju na dostupnu
terapiju, odgovor na terapiju tijekom liječenja smanjuje se ili terapija dovodi do o biljnih
nuspojava Upravo su i tog ra loga ra vijeni novi, sigurniji i učinkovitiji lijekovi – modulatori
S1P receptora. Etrasimod je novi lijek za pacijente s upalnom bolesti crijeva, a prvenstveno za one
oboljele od ulceroznog kolitisa. Selektivni je modulator S1PR1-a, S1PR4-a i S1PR5-a koji učinak
ostvaruje na način da inhibira promet limfocita i limfnih čvorova u krv Modulacija sfingo in-1-
fosfat receptora novi je put djelovanja lijekova koji se trenutačno ispituje ne samo a liječenje
upalnih bolesti crijeva, nego i za druge imunosne bolesti. U ovom je diplomskom radu razvijena
analitička metoda a odreĎivanje etrasimoda primjenom tekućinske kromatografije visoke
djelotvornosti Metoda je validirana sukladno meĎunarodno relevantnim smjernicama te je
utvrĎeno kako je metoda linearna, preci na i točna Predložena metoda može poslužiti kao temelj
za daljnje stabilitetno-indikativne studije.Inflammatory bowel disease (IBD) is an unpredictable chronic condition whose incidence is
continuously increasing. Based on the localization of pathological changes and the various
involvement of the digestive tract wall, we can differentiate between ulcerative colitis and Crohn's
disease. There are numerous approved medications available on the market for treating these
conditions, but many patients do not respond to the available therapy, and the response to therapy
during treatment decreases over time or leads to serious side effects. It is precisely for this reason
that newer, safer, and more effective drugs have been developed – S1P receptor modulators.
Etrasimod is a novel drug for patients with inflammatory bowel disease, primarily those suffering
from ulcerative colitis. It is a selective modulator of S1PR1, S1PR4, and S1PR5 receptors, exerting
its effects by inhibiting the lymphocyte trafficking from lymph nodes to the bloodstream.
Modulation of sphingosine-1-phosphate receptors represents a new mechanism of action being
currently investigated not only for the treatment of inflammatory bowel diseases but also for other
immune disorders. In this thesis, an analytical method for the determination of etrasimod using
high-performance liquid chromatography has been developed. The method has been validated
according to internationally recognized guidelines, demonstrating linearity, precision, and
accuracy. The proposed method can serve as a basis for further stability-indicating studies
Determining bioactive substances and antioxidant activity in dietary supplements for the treatment of inflammatory bowel diseases
No full textUpalne bolesti crijeva su kronične, idiopatske, relapsirajuće bolesti koje danas predstavljaju veliki
javnozdravstveni problem i zahvaćaju sve veći broj ljudi. Podijeljene su u dvije velike podgrupe:
Crohnova bolest i ulcerozni kolitis, ovisno o dijelu gastrointestinalnog trakta kojeg zahvaćaju upalni
procesi. Budući da su zahtjevi za biljnom terapijom među pacijentima s upalnim bolestima crijeva
sve veći zbog brojnih pozitivnih učinaka biljnih vrsta, cilj ovog rada bio je procijeniti kvalitetu
dodataka prehrani za liječenje upalnih bolesti crijeva obzirom na pojedinačne polifenole, odnosno
biološki aktivne tvari u tim dodacima, te odrediti antioksidativnu aktivnost istih. Sadržaj
pojedinačnih biološki aktivnih tvari u analiziranim uzorcima određen je tekućinskom
kromatografijom visoke djelotvornosti u kombinaciji s detektorom s nizom dioda, dok je
antioksidativna aktivnost procijenjena RPA metodom. Analizirani dodaci prehrani koji sadrže
kurkumu i indijski tamjanovac moga su se smatrati dobrim izvorom biološki aktivnih sastavnica.
Antioksidativna aktivnost monopreparata kurkume bila je veća nego kod ostalih analiziranih
monopreparata smole indijskog tamjanovca, te multipreparata kurkume, sporiša, kore limuna i crnog
papra. Nadalje, postoji značajna razlika u sadržaju DMC-a i CUR-a između analiziranih
monopreparata kurkume, kao i u sadržaju AKBA-e između analiziranih monopreparata smole
indijskog tamjanovca.Inflammatory bowel diseases are chronic, idiopathic, relapsing conditions that pose a significant public
health problem today, affecting an increasing number of people. They are divided into two major
subgroups: Crohn's disease and ulcerative colitis, depending on the part of the gastrointestinal tract
affected by inflammatory processes. As the demand for herbal therapy among patients with
inflammatory bowel diseases is growing due to the numerous positive effects of plant species, this work
aimed to assess the quality of dietary supplements for the treatment of inflammatory bowel diseases in
terms of individual polyphenols, i.e., bioactive substances in these supplements, and to determine their
antioxidant activity. The content of individual polyphenols in the analyzed samples was determined by
high-performance liquid chromatography combined with a diode array detector, while the antioxidant
activity was evaluated using the RPA method. The analyzed dietary supplements containing turmeric
and Indian frankincense can be considered as a good source of bioactive components. The antioxidant
activity of curcumin monopreparations was higher compared to other analyzed monopreparations of
Boswellia resin, as well as multipreparations of curcumin, sage, lemon peel, and black pepper.
Furthermore, there is a significant difference in content of DMC and CUR among the analyzed curcumin
monopreparations, as well as in content of AKBA among the analyzed Boswellia resin
monopreparations
Spectrophotometric determination of total polyphenols and antioxidant activity of dietary supplements for the treatment of inflammatory bowel diseases
No full textUpalne bolesti crijeva, Chronova bolest i ulcerozni kolitis, kronične su relapsno-remitirajuće bolesti
koje postaju sve češće te narušavaju kvalitetu života mnogih ljudi. Mnogi se, uz farmakoterapiju,
okreću alternativnoj medicini i ekstraktima biljaka koje imaju protuupalno i antioksidativno
djelovanje zahvaljujući polifenolima koje sadrže. Cilj ovog diplomskog rada bio je procijeniti
kvalitetu pribavljenih dodataka prehrani za liječenje upalnih bolesti crijeva s obzirom na njihov
sadržaj ukupnih polifenola i antioksidativne aktivnosti. Sadržaj ukupnih polifenola određen je
spektrofotometrijski korištenjem Folin-Ciocalteu reagensa, a antioksidativna aktivnost procijenjena
je ABTS metodom. Sadržaj ukupnih polifenola monopreparata kurkume bio je veći nego u ostalih
analiziranih preparata. Najveća antioksidativna aktivnost bila je kod monopreparata piperina.
Ispitivani uzorci koji sadrže kurkumu, indijski tamjanovac, justiciju i crni papar mogu se smatrati
dobrim izvorom polifenolnih sastavnica.Inflammatory bowel diseases, Crohn's disease and ulcerative colitis are chronic relapsing-remitting
diseases that are becoming increasingly common and impair the life quality of many people. Many
patients, in addition to pharmacotherapy, turn to alternative medicine and plant extracts that have
anti-inflammatory and antioxidant effects thanks to the polyphenols they contain. This thesis aimed
to evaluate the quality of the obtained nutritional supplements for the treatment of inflammatory
bowel diseases with regard to their content of total polyphenols and antioxidant activity. The content
of total polyphenols was determined spectrophotometrically using the Folin-Ciocalteu reagent, and
the antioxidant activity was assessed using the ABTS method. The content of total polyphenols in
the turmeric monopreparation was higher than in the other analyzed preparations. The highest
antioxidant activity was found in monopreparations of piperine. Tested samples containing turmeric,
Indian frankincense, justice, and black pepper can be considered as a good source of polyphenol
components
Analysis of ribociclib and anastrozole using HPLC-DAD method in blood plasma after protein precipitation
No full textAnastrozol i ribociklib koriste se u kombinaciji kao inicijalna endokrina terapija ER pozitivnog tumora dojke u
postmenopauzalnih žena. Anastrozol djeluje na smanjenje raspoloživog estrogena u tijelu koji je potreban za proliferaciju tumora,
dok ribociklib usporava stanični ciklus tumorskih stanica na taj način smanjujući mogućnost nastanka rezistencije na terapiju.
Cilj rada bio je razviti selektivnu analitičku metodu za istovremenu analizu ribocikliba i anastrozola u ljudskoj plazmi kao
temelj daljnjem razvoju osjetljive metode za određivanje ovih lijekova u plazmi pacijenata.
U tekućinskoj kromatografiji visoke djelotvornosti korištena je stacionarna faza XBridge (Waters) Phenyl (4,6 x 150 mm,
3,5 μm). Temperatura kolone podešena je na 25 °C. Ispitane su mobilne faze različitih omjera acetonitrila i vode s 0,1 %-tnom
mravljom kiselinom. Ispitana je izokratna eluacija i gradijentno ispiranje, kao i različite brzine protoka mobilne faze. Najpovoljnijom se pokazala gradijentna eluacija u kojoj se omjer vode i acetonitrila mijenjao sa 75:25 na 15:85 (V/V) u prvih 6 minuta analize pri brzini protoka od 0,5 mL/min, pri čemu su vremena zadržavanja ribocikliba i anastrozola iznosila 6,4 min i 8,7 min. Za detekciju je korišten detektor niza dioda. Određeni su UV-spektri oba analita te odabrane valne duljine detekcije od 220 nm za anatrozol i 270 nm za ribociklib. Radi izbjegavanja solvent effecta prilikom primjene acetonitrila, kao optimalno otapalo za analizu korištena je smjesa metanola i vode u omjeru 50:50 (V/V). Fenazon je odabran kao unutarnji standard zbog sličnog ponašanja analitima prilikom obrade složenog biološkog uzorka, pogodnog vremena zadržavanja (6,16 min) i svojstava (polarnost, molekulska masa) bliskih analitima. Plazma je po standardnom je postupku uz EDTA kao antikoagulans centrifugiranjem ekstrahirana iz pune krvi. Za uklanjanje matriksa, odnosno taloženje proteina plazme isprobane su metode s različitim omjerima metanola i acetonitrila uz i bez dodatka fosfatne kiseline. Fosfatna kiselina u dodatku organskim otapalima nije pokazala značajno smanjenje interferencija,dok je za taloženje proteina s metanolom potreban vrlo velik voluemn otapala. Optimalnim se pokazao postupak taloženja proteina acetonitrilomm u volumnom omjeru acetonitril:plazma 4:1, uz uparavanje otapala do suha i resuspendiranjem u 50 %-tnom metanolu. Prema ICH smjernicama za validaciju bioanalitičkih metoda na šest slijepih uzoraka plazme šestero različitih donora ispitana je selektivnost razvijene metode.Anastrozole and ribociclib are used in combination as initial endocrine therapy for ER-positive breast tumors in
postmenopausal women. Anastrozole works to reduce the available estrogen in the body, which is necessary for tumor proliferation, while ribociclib slows down the cell cycle of tumor cells, thereby reducing the possibility of resistance to therapy. The objective of this work was to develop a selective analytical method for the simultaneous analysis of ribociclib and anastrozole in human plasma as a basis for further development of a sensitive method for determining these drugsin patients' plasma. XBridge (Waters) Phenyl (4.6 x 150 mm, 3.5 μm) stationary phase was used in high-performance liquid chromatography. The column temperature was set at 25 °C. Various mobile phase combinations of acetonitrile and water with 0.1% formic acid were tested, including isocratic elution, gradient washing, and different mobile phase flow rates. The most favorable method was gradient elution, where the ratio of water to acetonitrile changed from 75:25 to 15:85 (V/V) during the first 6 minutes of the analysis, with a flow rate of 0.5 mL/min. The retention times for ribociclib and anastrozole were 6.4 min and 8.7 min, respectively. A diode array detector was employed for detection. The UV spectra of both analytes and the selected detection wavelengths of 220 nm for anastrozole and 270 nm for ribociclib were determined. To mitigate the solvent effect when using acetonitrile, a mixture of methanol and water in a ratio of 50:50 (V/V) was utilized as the optimal solvent for the analysis. Phenazone was chosen as an internal standard due to its similar behavior to the analytes when processing complex biological samples, its convenient retention time (6.16 min), and properties (polarity, molecular weight) close to those of the analytes. The plasma is extracted from whole blood by centrifugation using EDTA as an anticoagulant in accordance with the standard procedure. Various methods involving different ratios of methanol and acetonitrile, with and without the addition of phosphoric acid, were tested for matrix removal, which refers to the deposition of plasma proteins. The addition of phosphoric acid to organic solvents did not significantly reduce interferences, while protein precipitation with methanol required a large volume of solvent. The protein precipitation method with acetonitrile in a volume ratio of acetonitrile:plasma of 4:1, followed by solvent evaporation to dryness and resuspension in 50% methanol, proved to be optimal. In accordance with the ICH guidelines for the validation of bioanalytical methods, the selectivity of the developed method was tested using six blank plasma samples from six different donors