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Biocompatibility study of azithromycin-loaded deformable liposomes incorporated into chitosan and carbopol gel
No full textPrilikom razvoja hibridnih formulacija liposomi-u-gelu, potrebno je voditi računa ne samo o
učinkovitosti i biofarmaceutskim karakteristikama formulacije, već i o biokompatibilnosti s
odabranim staničnim kulturama. U sklopu ovog istraživanja deformabilni liposomi s AZT-om (DL)
uklopljeni su u 2 različita gela: kitozanski gel (CHG) i karbopolski gel (CAG), s ciljem ispitivanja i
usporedbe biokompatibilnosti dobivenih formulacija liposomi-u-gelu in vitro na HaCaT staničnoj
liniji. Formulacija DL-CHG je u rasponu koncentracija ≤ 32 μg/ml biokompatibilna s HaCaT
stanicama, dok je pri koncentraciji 64 μg/ml vijabilnost stanica bila ˂ 70 % te se može smatrati
citotoksičnom za HaCaT stanice. U usporedbi s formulacijom DL-CHG, DL-CAG pokazuje
biokompatibilnost u širem rasponu koncentracija (0,25 64 μg/ml), te je pri najvišoj testiranoj
koncentraciji vijabilnost tretiranih stanica veća u odnosu na formulaciju DL-CHG pri istoj
koncentraciji, zbog čega se CAG može smatrati prikladnijom podlogom za uklapanje DL od CHG.
Budući da su se gelovi s uklopljenim neliposomskim lijekom također pokazali citotoksičnima pri
visokim koncentracijama AZT-a, čini se da citotoksičnost formulacija DL-u-gelu pri koncentraciji
64 μg/ml proizlazi djelomično iz prisutnosti samog AZT-a u formulaciji, a djelomično je odgovoran
sastav liposomske formulacije DL.During the development of hybrid liposome-in-gel formulations, it is essential to consider not
only the efficacy and biopharmaceutical characteristics of the formulation but also biocompatibility
with selected cell cultures. In this study, AZT-loaded deformable liposomes (DL) were incorporated
into two different gels: chitosan gel (CHG) and carbopol gel (CAG), with the aim of testing and
comparing the biocompatibility of the obtained liposome-in-gel formulations in vitro on the HaCaT
cell line. The DL-CHG formulation was biocompatible with HaCaT cells at a concentration ≤ 32
μg/ml, while at a concentration ≥ 64 μg/ml, cell viability was ˂ 70%, which can be considered
cytotoxic. Compared with the DL-CHG formulation, DL-CAG shows biocompatibility over a wider
range of concentrations (0.25 64 μg/ml). Moreover, at the highest tested concentration, the viability
of treated cells was greater compared to the DL-CHG formulation, making CAG a more suitable
vehicle for incorporating DL from a biocompatibility standpoint. Since gels with incorporated nonliposomal
AZT also exhibited cytotoxicity at high concentrations, it seems that the cytotoxicity of the
DL-in-gel formulations at concentrations ≥ 64 μg/ml arises partly from the presence of AZT itself in
the formulation, and partly from the composition of the DL liposome formulation
Validation of the LC-MS/MS bioanalytical method for the analysis of ribociclib and anastrozole using solid-phase extraction
No full textAnastrozol i ribociklib se u kombiniranoj primjeni koriste za liječenje ER pozitivnih tumora dojke kod žena
u postmenopauzi. Cilj rada bio je validirati analitičku metodu za istovremenu analizu ribocikliba i anastrozola u ljudskoj
plazmi.
Kromatografska separacija analita provodila se na XBridge Phenyl koloni pri temperaturi 35 °C. Primijenjena
je gradijentna eluacija kombinacijom mobilnih faza (A: voda i mravlja kiselina; B: metanol i mravlja kiselina), uz brzinu
protoka 0,6 mL/min. Detekcija je vršena pomoću spektrometra masa (fragmentacija ribociklib m/z 435.2→ m/z
322.1(25eV) + m/z 252.1(30eV), anastrozol m/z 294.1→ m/z 225.4 (25eV) + m/z 115.2 (70eV)).
Linearnost metode ispitana je na rasponu koncentracija od 700 do 3500 ng/mL za ribociklib te od 20 do
100ng/ml za anastrozol. Preciznost i točnost metode ispitavani su na 3 koncentracijske razine (LLOQ, do 3xLLOQ,
80%ULOQ). Dobivene su zadovoljavajuće RSD vrijednosti ponovljivosti (ribociklib → 4,71%, 1,33%, 1,51%;
anastrozol → 9,23%, 6,43%, 4,31%) i srednje preciznosti (ribociklib → 6,23%, 3,97%, 2,28%; anastrozol → 11,35%,
11,40%, 14,78%). Izračunati analitički prinosi (ribociklib: unutar dana → 11,22%, 8,94%, −3,95%; između dana →
−1,85%, 8,21%, −3,89%; anastrozol: unutar dana → −10,92%, −6,12%, −4,55%; između dana → −8,98%, −4,66%,
−1,55%) zadovoljili su validacijski kriterij točnosti. Ispitani su i parametri injekcijske reproducibilnosti (RSD<7%) i
carry-over efekta (<2%) te su dobivene vrijednosti oba parametra zadovoljile validacijske kriterije. Prema ICH
smjernicama za validaciju bioanalitičkih metoda na šest slijepih uzoraka plazme (različitih donora) na visokim i niskim
koncentracijama ispitan je utjecaj matriks efekta na rezultate. Prilikom određivanja ribocikliba došlo je do ionskog
pojačanja u svim uzorcima, osim u hemolitičkom i lipemičnom. Utjecaj matriksa kod anastrozola uzrokovao je ionsku
supresiju reproducibilnu kroz sve uzorke i ispitane koncentracijske razine. Po svim ispitanim validacijskim parametrima
ova je metoda zadovoljavajuća za istovremeno određivanje koncentracije ribocikliba i anastrozola u plazmi.Anastrozole and ribociclib are used in combination for the treatment of ER-positive breast tumors
in postmenopausal women. The aim of this study was to validate an analytical method for the simultaneous
analysis of ribociclib and anastrozole in human plasma.
Chromatographic separation of the analytes was performed on an XBridge Phenyl column at a
temperature of 35 °C. Gradient elution was applied using mobile phases (A: water and formic acid; B:
methanol and formic acid) at a flow rate of 0.6 mL/min. Detection was carried out using a mass spectrometer
(ribociclib fragmentation m/z 435.2→ m/z 322.1 (25eV) + m/z 252.1 (30eV), anastrozole m/z 294.1→ m/z
225.4 (25eV) + m/z 115.2 (70eV)).
The linearity of the method was tested in the concentration range of 700 to 3500 ng/mL for ribociclib
and 20 to 100 ng/mL for anastrozole. Precision and accuracy of the method were tested at three concentration
levels (LLOQ, up to 3xLLOQ, 80% ULOQ). Satisfactory RSD values for repeatability (ribociclib → 4.71%,
1.33%, 1.51%; anastrozole → 9.23%, 6.43%, 4.31%) and intermediate precision (ribociclib → 6.23%, 3.97%,
2.28%; anastrozole → 11.35%, 11.40%, 14.78%) were obtained. The calculated analytical recoveries
(ribociclib: within-day → 11.22%, 8.94%, −3.95%; between-day → −1.85%, 8.21%, −3.89%; anastrozole:
within-day → −10.92%, −6.12%, −4.55%; between-day → −8.98%, −4.66%, −1.55%) met the accuracy
validation criteria. Injection reproducibility parameters (RSD<7%) and carry-over effect (<2%) were also
tested, and the obtained values for both parameters met the validation criteria. According to ICH guidelines
for the validation of bioanalytical methods, the matrix effect on the results was tested on six blank plasma
samples (from different donors) at high and low concentrations. During the determination of ribociclib, ion
enhancement occurred in all samples except the hemolytic and lipemic ones. The matrix effect for anastrozole
caused ion suppression, which was reproducible across all samples and tested concentration levels. Based on
all the tested validation parameters, this method is satisfactory for the simultaneous determination of
ribociclib and anastrozole concentrations in plasma
Kardiovaskularna sigurnost lijekova za liječenje osteoporoze
No full textCilj istraživanja
Cilj ovog specijalističkog rada je pokazati u kolikoj mjeri su lijekovi za liječenje osteoporoze
povezani s pojavom neželjenih kardiovaskularnih učinaka i kako iste minimizirati odabirom
odgovarajuće terapije, s obzirom na ostale čimbenike rizika.
Materijali i metode
U izradi rada koristit će se pregled objavljene literature o kardiovaskularnoj sigurnosti i
nuspojavama lijekova za liječenje osteoporoze. Pregledom znanstvene literature pokušat ćemo
bolje objasniti patofiziološku vezu između osteoporoze i vaskularne kalcifikacije, koja je
snažan prediktor neželjenih kardiovaskularnih događaja, što je neophodno za bolje
razumijevanje ovih bolesti i smanjenja rizika od komplikacija.
Rezultati
Bisfosfonati, kao najčešće korišteni antiresorptivni lijekovi, smanjuju rizik od
kardiovaskularne smrtnosti, iako su pokazali proaritmijski potencijal, zbog čega je potreban
oprez kod pacijenata s rizikom od atrijske fibrilacije. Denosumab, kao najčešći izbor kod
pacijenata kod kojih primjena bisfosfonata nije moguća, pokazao se dugoročno općenito
sigurnim kod kardiovaskularnih pacijenata. Selektivni modulatori estrogenskih receptora i
raloksifen pokazali su povećan rizik od infarkta miokarda i moždanog udara, zbog čega se
njihova upotreba ne preporuča kod rizičnih pacijenata. Nije zabilježen povećan
kardiovaskularni rizik nakon primjene teriparatida i abaloparatida. Romosozumab je u nekim
studijama pokazao povećan rizik od infarkta miokarda i drugih neželjenih kardiovaskularnih
događaja, dok u drugim studijama nije imao značajnog utjecaja. S obzirom na oprečne
rezultate kardiovaskularna sigurnost romosozumaba nastavlja se ocjenjivati kroz kontinuirani
postmarketinški nadzor i studije u stvarnom svijetu.
Zaključak
Osteoporotični prijelomi odgovorni su za trajni invaliditet, smanjenu kvalitetu života i
povećanu smrtnost, a ujedno predstavljaju golemi financijski teret za samog pacijenta te za
nacionalno gospodarstvo. Iako smjernice koje bi trebale biti usmjerene na kardiovaskularnu
sigurnost lijekova za liječenje osteoporoze i dalje ne postoje, osteoporoza se može
dijagnosticirati i spriječiti učinkovitim tretmanima, prije nego što dođe do prijeloma te bi
obveza pružatelja primarne zdravstvene zaštite trebala bi biti prevencija, otkrivanje i liječenje
osteoporoze.
S dostupnim antiresorpcijskim lijekovima i sve većim popisom anaboličkih opcija za liječenje
osteoporoze mogao bi se značajno smanjiti teret koji osteoporoza i posljedični prijelomi
predstavljaju za javno zdravstvo.Objective
The aim of this expert thesis is to show to what extent the drugs for the treatment of
osteoporosis are associated with the occurrence of unwanted cardiovascular effects and how
to minimize them by choosing the appropriate therapy, taking into account other risk factors.
Materials and methods
A review of the published literature on cardiovascular safety and side effects of drugs for the
treatment of osteoporosis will be used in the preparation of the paper. By reviewing the
scientific literature, we will try to better explain the pathophysiological link between
osteoporosis and vascular calcification, which is a strong predictor of unwanted
cardiovascular events, which is necessary for a better understanding of these diseases and
reducing the risk of complications.
Results
Bisphosphonates, as the most commonly used antiresorptive agents, reduce the risk of
cardiovascular mortality, although they have shown proarrhythmic potential, which is why
caution is needed in patients at risk of atrial fibrillation. Denosumab, as the most common
choice in patients in whom bisphosphonates are not an option, has been shown to be generally
safe in cardiovascular patients. Selective estrogen receptor modulators and raloxifene have
shown an increased risk of myocardial infarction and stroke, which is why their use is not
recommended in high-risk patients. No increased cardiovascular risk was reported after the
use of teriparatide and abaloparatide. Romosozumab has shown an increased risk of
myocardial infarction and other adverse cardiovascular events in some studies, while in other
studies it had no significant effect. Given the conflicting results, the cardiovascular safety of
romosozumab continues to be evaluated through continued postmarketing surveillance and
real-world studies.
Conclusion
Osteoporotic fractures are responsible for permanent disability, reduced quality of life and
increased mortality, and at the same time represent a huge financial burden for the patient and
the national economy. Although guidelines that should focus on the cardiovascular safety of
drugs for the treatment of osteoporosis still do not exist, osteoporosis can be diagnosed and
prevented with effective treatments, before a fracture occurs, and prevention, detection and
treatment of osteoporosis should be the responsibility of primary care providers.
With the availability of antiresorptive drugs and a growing list of anabolic options for the
treatment of osteoporosis, the public health burden of osteoporosis and consequent fractures
could be significantly reduced
Procjena potrebe za depreskripcijom oralnih antikoagulanasa i inhibitora agregacije trombocita u nehospitaliziranih osoba starije životne dobi
No full textCilj istraživanja: Cilj istraživanja je procijeniti prikladnost terapije oralnim antikoagulansima ili
inhibitorima agregacije trombocita kod bolesnika starije životne dobi koristeći kriterije za depreskripciju, te odrediti udio bolesnika kojima bi potencijalna depreskripcija bila korisna.
Ispitanici i metode: Pomoću upitnika razvijenog za potrebe ovog istraživanja u sklopu EuroAgeism Horizon 2020 projekta prikupljeni su podaci u javnim ljekarnama Republike Hrvatske na
području Zagreba, Istre i Slavonije u periodu od ožujka 2019. do ožujka 2020. Prikupljeni su
podaci za 391 pacijenta starije životne dobi (>65 godina), a zatim su identifirana 124 pacijenta
s promatranim lijekovima za depreskripciju u terapiji i sve daljnje analize rađene su na toj populaciji. Provedeno je opservacijsko, neintervencijsko istraživanje. Uključni kriteriji su bili životna dob 65 godina ili više i stabilno zdravstveno stanje (pacijenti koji nisu na intenzivnoj njezi,
nemaju akutno pogoršanje zdravstvenog stanja koje zahtijeva hospitalizaciju i nisu bili na odjelu hitne službe u posljednja tri dana i pacijenti kojima nije potrebna palijativna skrb). Svi
uključeni pacijenti su svojevoljno potpisali informirani pristanak. Istraživanje je odobrilo Povjerenstvo za etičnost eksperimentalnog rada Farmaceutsko-biokemijskog fakulteta Sveučilišta u Zagrebu.
Koristeći smjernice za depreskripciju antitrombotika (PrescoIPP Community interest company:
IMPACT - Improving Medicines and Polypharmacy Appropriateness Clinical Tool) i smjernice za
depreskripciju lijekova kod starije populacije (Better medicine), odlučivalo se o potrebi za potencijalnom depreskripcijom antikoagulanasa i inhibitora agregacije trombocita. U svrhu statističke analize koristile su se deskriptivne metode.
Rezultati: U ispitivanju je sudjelovao 124 pacijent (64 žene i 60 muškaraca). Prosječna je dob
ispitanika bila 75,01 (SD=6,8) godine, a u terapiji su imali prosječno 8 lijekova. Acetilsalicilatnu
kiselinu je koristilo 73 pacijenta (58,87%), klopidogrel 10 pacijenata (8,06%), a tikagrelor 1 pacijent (0,81%). Apiksaban je koristio 1 pacijent (0,81%), dabigatraneteksilat 6 pacijenata
(4,84%), rivaroksaban 8 pacijenata (6,45%) a varfarin 25 pacijenata (20,16%).
Pomoću kriterija za depreskripciju dobiveni su rezultati da bi 54 pacijenta (43,55%) moglo imati korist od depreskripcije inhibitora agregacije trombocita. Najviše ispitanika kandidati su
za depreskripciju prema kriteriju A (ne postoji jasna indikacija za korištenje lijeka), a zatim slijedi kriterij B (indikacija za korištenje lijeka postoji ali je trenutno trajanje terapije predugo).
Također, tri pacijenta (2,42%) bi mogla imati korist od depreskripcije oralnih antikoagulanasa.
Navedeni pacijenti kandidati su za depreskripciju prema kriteriju A i prema kriteriju C (postoji
opravdana indikacija za korištenje lijeka ali je doza lijeka previsoka, pa je moguće provesti depreskripciju smanjenjem doze).
Zaključak: Rezultati ovog istraživanja pokazali su da postoji potreba za racionalnijim korištenjem antiagregacijskih i antikoagulacijskih lijekova u bolesnika starije životne dobi, te da bi
neki od bolesnika mogli imati koristi od njihove depreskripcije. Ukidanjem lijekova za koje je
procijenjen viši rizik od korist, smanjila bi se mogućnost nuspojava i mogućih interakcija s drugim lijekovima u terapiji, a zdravstveni sustav i pacijent ostvarili bi financijsku uštedu.Aim of the study: The aim of the study is to assess the appropriateness of therapy with oral
anticoagulants or platelet aggregation inhibitors in elderly patients using criteria for deprescription, and to determine the proportion of patients who would benefit from potential
deprescription.
Subjects and methods: Data were collected from public pharmacies in the Republic of Croatia,
in the areas of Zagreb, Istria and Slavonia, between March 2019 to March 2020. The study was
conducted as part of the Euro-Ageism Horizon 2020 project, using a questionnaire developed
for this research. Data were gathered for 391 elderly patients (>65 years), of which 124 patients using deprescription-related drugs in therapy were identified for further analyzes. This
was an observational, non-interventional study. The inclusion criteria were: age 65 years or
older and stable health status (i.e. patients not in intensive care, without acute health deterioration requiring hospitalization, without recent visits to the emergency department in the
last three days, and not requiring palliative care ). All patients voluntarily signed informed
consent form. The research was approved by the Committee for the Ethics of Experimental
Work of the Faculty of Pharmacy and Biochemistry of the University of Zagreb.
The need for potential deprescription of anticoagulants and platelet aggregation inhibitors
was determined using the guidelines for antithrombotic deprescription (PrescoIPP Community
interest company: IMPACT - Improving Medicines and Polypharmacy Appropriateness Clinical
Tool) and deprescription guidelines for the elderly (Better medicine). Descriptive statistical
methods were used for data analysis.
Results: A total of 124 patients (64 women and 60 men) participated in the study. The average
age of the subjects was 75,01 (SD=6,8) years, and they were taking an average of eight medications. Acetylsalicylic acid was used by 73 patients (18.67%), clopidogrel by 10 patients
(2.56%), and ticagrelor by 1 patient (0.26%). Apixaban was used by 1 patient (0.26%),
dabigatranetexilat by 6 patients (1.53%), rivaroxaban by 8 patients (2.05%) and warfarin by 25
patients (6.39%).
Based on deprescription criteria, it was found that 54 patients (43.55%) could benefit from
deprescription of platelet aggregation inhibitors. Most respondents are candidates for deprescription under criterion A (no clear indication for the drug’s use), followed by criterion B (indication exists, but the duration of therapy is too long). Additionally, three patients (2.42%)
could benefit from deprescription of oral anticoagulants, based on criteria A and C (a justified
indication exists, but the drug dosage is too highallowing for deprescription by dose reduction).
Conclusion: The results of this study suggest a need for more rational use of antiplatelet and
anticoagulation drugs in elderly patients. Some patients could benefit from deprescription,
which could ultimately reduce the risk of side effects and potential drug interactions. This
would also result in financial savings for both the healthcare system and the patients
Biljne droge za ublažavanje nesanice
No full textCilj istraživanja
Cilj ovog specijalističkog rada je sveobuhvatan pregled dostupne znanstvene i stručne literature
o biljnim drogama koje se primjenjuju za ublažavanje nesanice. Svrha je stjecanje znanja o
njihovim učincima i mehanizmima djelovanja kod osoba s nesanicom.
Materijali i metode
Istraživanje u okviru ovog rada je teorijskog karaktera i uključuje pregled dostupne znanstvene i
stručne literature o kliničkim kao i nekliničkim istraživanjima vezanim uz predloženu temu. U
pretraživanju su korištene dostupne bibliografske baze podataka Web of Science, PubMed
(Medline), Scopus, Science Direct i Cochrane Library.
Rezultati
Biljni pripravci imaju značajnu ulogu u ublažavanju nesanice. Znanstvena literatura potvrđuje da
biljne vrste poput odoljena (Valeriana officinalis L.), matičnjaka (Melissa officinalis L.), šafrana
(Crocus sativus L.) i ašvagande (Withania somnifera (L.) Dunal) imaju značajan pozitivan učinak
u ublažavanju simptoma nesanice. Kliničke studije rađene na odoljenu pokazuju poboljšanje
kvalitete sna, posebno kod osoba s anksioznošću i nesanicom. Kliničke studije pripravaka
matičnjaka potvrđuju njegovu učinkovitost u smanjenju anksioznosti i poboljšanju kvalitete sna.
Klinička ispitivanja pripravaka koje sadrže ašvagandu ili šafran pokazuju obećavajuće rezultate,
ali su potrebna daljnja ispitivanja za potvrdu optimalnih doza i potencijalnih nuspojava.
Zaključak
Ovi rezultati ukazuju da biljni pripravci mogu poboljšati kvalitetu sna i pomoći osobama s
nesanicom. No, potrebno je više istraživanja kako bi se potvrdila njihova sigurnost i učinkovitost.
Dostatni klinički dokazi omogućili bi opsežnije uvođenje biljnih pripravaka u terapiju nesanice,
čime bi se posljedično smanjila upotreba sintetskih lijekova koji dugoročnim uzimanjem pokazuju
negativne učinke na zdravlje i kvalitetu života.Objectives
This research aims to provide a comprehensive review of the available scientific and professional
literature on herbal drugs most used to alleviate insomnia. The purpose is to learn about their
effects and mechanisms of action in individuals with insomnia.
Materials and methods
The research in this paper is theoretical and includes a review of the available scientific and
professional literature on both clinical and non-clinical studies related to the proposed topic. The
search utilized available bibliographic databases such as Web of Science, PubMed (Medline),
Scopus, Science Direct, and Cochrane Library.
Results
Herbal preparations play a significant role in alleviating insomnia. Scientific literature confirms that
plant species such as valerian (Valeriana officinalis L.), lemon balm (Melissa officinalis L.), saffron
(Crocus sativus L.), and ashwagandha (Withania somnifera (L.) Dunal) have a notable positive
effect on reducing insomnia symptoms. Clinical studies on valerian show an improvement in sleep
quality, especially in individuals with anxiety and insomnia. Clinical studies of lemon balm
preparations confirm its effectiveness in reducing anxiety and improving sleep quality. Clinical
trials of preparations containing ashwagandha or saffron show promising results, but further
research is needed to confirm optimal doses and potential side effects.
Conclusion
These results suggest that herbal drugs can be beneficial for improving sleep quality and
supporting individuals with insomnia. However, more research is needed to confirm their safety
and efficacy. This could contribute to directing insomnia therapy towards herbal preparations,
thereby reducing the use of synthetic drugs, which have shown negative effects on health and
quality of life when used long-term
Challenges of parabens use as preservatives in pharmaceutical dosage forms and cosmetics
No full textCilj ovog diplomskog rad je opisati djelovanje estera p-hidroksibenzoatne kiseline kao pomoćnih tvari koje dodaju različitim farmaceutskim oblicima te kozmetičkim proizvodima. Njihovom upotrebom postiže se odgovarajući rok trajnosti jer suzbijaju rast štetnih mikroorganizama. Osim kemijske stabilnosti i dobrog antimikrobnog učinka, parabeni pokazuju minimalni učinak na mikrobiom kože. Najzastupljeniji su u farmaceutskim oblicima i kozmetičkim pripravcima koji se primjenjuju na kožu. Prosječan dnevni unos parabena u odraslih osoba varira između 1 μg/kg iz hrane i 0.833 mg/kg preko kozmetičkih pripravaka za njegu, zaštitu, čišćenje te parfimiranje kože. S obzirom da se brzo metaboliziraju u netoksične metabolite, njihova primjena se smatra sigurnom. Međutim, kronična primjena proizvoda konzerviranih parabenima može dovesti do njihovog nakupljanja u tkivima, no zdravstveni rizik koji može proizaći iz toga još nije poznat. U in vitro uvjetima pokazana je estrogena aktivnost parabena, pa se sumnja da mogu doprinijeti rastu o estrogenu ovisnih tumora. No ovdje se mora istaknuti kako je estrogenska aktivnost parabena od 2,5 milijuna do 10 000 puta manja u odnosu na fiziološki prisutan estrogen. Nadalje, izloženost parabenima u kombinaciji s ultravioletnim zračenjem može potaknuti nastanak reaktivnih kisikovih vrsta u staničnim kulturama keratinocita, no in vivo je taj učinak upitan. Kombinacijom parabena s drugim tvarima može se smanjiti njihova količina u pripravku, što što vodi smanjenoj izloženosti parabenima. Danas raste svijest o potrebi razvoja učinkovitijih metoda za uklanjanje parabena iz otpadnih voda, kako bi se isključio njihov potencijalno nepovoljan utjecaj na vodene organizme i ekosustav općenito.This thesis aims to describe the action of p-hydroxybenzoic acid esters as preservatives added to various pharmaceutical forms and cosmetic products. Their use enables them to achieve an appropriate shelf life by suppressing the growth of harmful microorganisms. In addition to chemical stability and a good antimicrobial effect, parabens show a minimal effect on the skin microbiome. They are most represented in pharmaceutical dosage forms and cosmetic preparations that are applied to the skin. The average daily intake of parabens in adults varies between 1 μg/kg from food and 0.833 mg/kg via cosmetic preparations for skin care, protection, cleansing and perfuming. As they are quickly metabolized into non-toxic metabolites, their use is considered safe. However, chronic use of paraben-preserved products can lead to their accumulation in tissues, however, the health risk arising from that is yet unknown. The estrogenic activity of parabens has been demonstrated in vitro, so it is suspected that they may contribute to the growth of oestrogen-dependent tumours. However, it must be noted that the estrogenic activity of parabens is 2.5 million to 10,000 times lower than that of physiologically present oestrogen. Furthermore, exposure to parabens in combination with ultraviolet radiation can induce the formation of reactive oxygen species in keratinocyte cell cultures, but in vivo this effect is questionable. By combining parabens with other substances, their amount in the preparation can be reduced, which leads to reduced exposure to parabens. Today, there is a growing awareness of the need to develop more effective methods for removing parabens from wastewater, to exclude their potentially unfavourable impact on the aquatic organism and the ecosystem in general
In situ gelling ophthalmic nanoemulsions for the treatment of dry eye disease
No full textBolest suhog oka je kompleksna, multifaktorijalna bolest površine oka karakterizirana gubitkom homeostaze suznog filma. Nanoemulzije predstavljaju inovativne terapijske sustave za oftalmičku primjenu koji omogućuju zadovoljavajuću bioraspoloživot, produljeno vrijeme zadržavanja na površini oka te nadoknadu i stabilizaciju suznog filma. In situ gelirajući oftalmički sustavi omogućuju produljeno vrijeme zadržavanja pripravka na mjestu primjene zahvaljujući karakterističnom faznom prijelazu iz tekućine u gel te predstavljaju jednu od inovativnih tehnoloških platformi za dostavu djelatnih tvari na površinu oka. Cilj ovog diplomskog rada bio je razviti in situ gelirajuće oftalmičke nanoemulzije s rastućom koncentracijom gelan gume (0,05-0,4%) kao gelirajućeg polimera čiji je fazni prijelaz potaknut fiziološki prisutnim kationima suzne tekućine te ispitati fizikalno-kemijska i reološka svojstva. Nanoemulzijama su izmjerene prosječne veličine kapljica, PDI, zeta potencijal i pH-vrijednost. Rezultati fizikalno-kemijskih mjerenja pokazali su da je prosječna veličina kapljica (141,1-172,9 nm), PDI je u rasponu prihvatljivih vrijednosti (0,108-0,222), vrijednosti zeta-potencijala su negativne vrijednosti (-33,0 do -44,9 mV) koje upućuju na zadovoljavajuću stabilnost formulacija, pH-vrijednost svih formulacija je prikladna za oftalmičku primjenu (6,06-6,18). Reološke karakteristike su ispitane krivuljom viskoznosti prije i nakon miješanja s ATS-om, te testom promjene amplitude nakon miješanja s ATS-om. Rezultati krivulje viskoznosti pokazali su da je jedino formulacija s najvećim udjelom gelan gume (0,4%) pseudoplastični sustav, dok su ostale formulacije Newtonovi sustavi. Na temelju testa promjene amplitude zaključeno je da kod formulacija s nižim udjelima gelan gume (0,05-0,1%) ne dolazi do geliranja nanoemulzija, dok kod formulacija s većim udjelima gelan gume (0,2 i 0,4%) dolazi do stvaranja gela na temelju interakcije kationa prisutnih u ATS-u i dostatne koncentracije gelan gume. S obzirom na dobivene rezultate formulacije s 0,2 i 0,4% gelan gume ističu se kao vodeće formulacije za daljnja ispitivanja u unaprjeđenju liječenja bolesti suhog oka.Dry eye disease is a complex, multifactorial condition of the ocular surface characterized by the loss of tear film homeostasis. Nanoemulsions represent innovative therapeutic systems for ophthalmic application that enable adequate bioavailability, prolonged retention time on the ocular surface, and replenishment and stabilization of the tear film. In situ gelling ophthalmic systems allow prolonged retention time of the formulation at the site of application due to the characteristic phase transition from liquid to gel, representing one of the innovative technological platforms for delivering active substances to the ocular surface. The aim of this thesis was to develop in situ gelling ophthalmic nanoemulsions with increasing concentrations of gellan gum (0.05-0.4%) as the gelling polymer, whose phase transition is induced by physiologically present cations in the tear fluid, and to investigate their physicochemical and rheological properties. The nanoemulsions were characterized for average droplet sizes, polydispersity index (PDI), zeta potential, and pH value. The results of physicochemical measurements showed that the average droplet size ranged from 141.1 to 172.9 nm, PDI fell within acceptable values (0.108-0.222), zeta potential values were negative (-33.0 to -44.9 mV), indicating satisfactory formulation stability, and the pH values of all formulations were suitable for ophthalmic application (6,06-6,18). Rheological characteristics were examined by viscosity curve analysis before and after mixing with ATS and by amplitude sweep test after mixing with ATS. The viscosity curve results showed that only the formulation with the highest concentration of gellan gum (0.4%) exhibited pseudoplastic behavior, while the other formulations were Newtonian systems. Based on the amplitude sweep test, it is concluded that in formulations with lower concentrations of gellan gum (0.05-0.1%), no gel formation occurred, whereas in formulations with higher concentrations of gellan gum (0.2 and 0.4%), gel formation occurred due to interaction between cations present in ATS and sufficient concentration of gellan gum. Considering the obtained results, formulations with 0.2 and 0.4% gellan gum stand out as leading formulations for further investigation in the improvement of dry eye disease treatment
Plan upravljanja istraživačkim podatcima-IP-2019-04-4624, Gensko, proteinsko i RNA profiliranje kolorektalnog karcinoma primjenom tekuće biopsije
No full textComplete blood count parameters and calculated haematological inflammation-related biomarkers in colorectal carcinoma
No full textPrema podatcima Svjetske zdravstvene organizacije i Hrvatskog zavoda za javno zdravstvo, CRC je treći po redu najučestaliji karcinom u svijetu te prvi u Hrvatskoj. Po smrtnosti, nalazi se na drugome mjestu, odmah nakon raka pluća, a bilježi oko 900 000 smrtnih slučajeva u 2020. godini. U posljednjem desetljeću zamijećen je porast broja oboljelih. Uz stariju životnu dob, čimbenici rizika za razvoj bolesti jesu i obiteljska povijest bolesti, upalne bolesti crijeva, pretilost, pušenje, prehrana bogata crvenim mesom, odnosno stil života. Cilj provedenog istraživanja bio je ispitati parametre KKS-a i biomarkere povezane s upalom, MPV/PC-a, PLR-a, NLR-a, LWR-a, LMR-a, NMR-a i LCR-a u pacijenata s CRC-om te onih s adenomom. Istraživanje je obuhvatilo 155 pacijenata podijeljenih u dvije grupe, 81 s CRC-om i 74 s adenomom, s obzirom na nalaz patohistološke analize. Parametri KKS-a određeni su na hematološkom analizatoru Symsex-XN (Sysmex Inc, Kobe, Japan), koncentracija CRP-a izmjerena je na analizatoru Alinity ci-series (Abbot Diagnostics, Abbot Park, IL, USA), a statistička analiza i analiza ROC krivulja napravljena je korištenjem MedCalc® statističkog softwarea verzije 22.014 (MedCalc Software Ltd, Ostend, Belgium). Koncentracija hemoglobina, hematokrit, MCV, MCH i MCHC bili su niži, a RDW viši u skupini pacijenata s CRC-om. Apsolutni broj leukocita, neutrofila i monocita niži je u pacijenata s CRC-om, dok je apsolutni i relativan broj eozinofila kao i relativni broj bazofila u istoj grupi bio viši negoli u skupini pacijenata s adenomom. Broj trombocita bio je značajno viši, a MPV značajno niži u skupini pacijenata s CRC-om. Od svih ispitanih biomarkera povezanih s upalom, jedino su MPV/PC i PLR pokazali statistički značajnu razliku između dviju skupina, uz niže vrijednosti MPV/PC-a i više vrijednosti PLR-a u skupini pacijenata s CRC-om. Unatoč postojanju razlike, analizom ROC krivulja niti jedan ispitani parametar nije pokazao zadovoljavajuću dijagnostičku točnost za razlikovanje dviju skupina.According to the World Health Organization’s and the Croatian Institute of Public Health’s data, CRC is the third most common cancer in the world and first in Croatia. In terms of mortality, it is in second place, right after lung cancer, with around 900,000 deaths in 2020. An increase in the number of patients has been observed in the last decade. In addition to older age, risk factors for the development of the disease also include a family history of diseases, inflammatory bowel diseases, obesity, smoking, a diet rich in red meat, or in other words, lifestyle. The aim of the research was to examine parameters of CBC and biomarkers related to inflammation, MPV/PC, PLR, NLR, LWR, LMR, NMR and LCR in CRC patients and those with adenoma. The research included 155 patients divided into two groups, 81 with CRC and 74 with adenoma, based on the pathohistological analysis. CBC parameters were determined on a Symsex-XN hematology analyzer (Sysmex Inc, Kobe, Japan), CRP concentration was measured on an Alinity ci-series analyzer (Abbot Diagnostics, Abbot Park, IL, USA), statistical and the ROC curve analysis was made using MedCalc® statistical software version 22.014 (MedCalc Software Ltd, Ostend, Belgium). Hemoglobin concentration, hematocrit, MCV, MCH and MCHC were lower, and RDW higher in the group of patients with CRC. The absolute number of leukocytes, neutrophils and monocytes was lower in patients with CRC, while the absolute and relative number of eosinophils as well as the relative number of basophils in the same group was higher than in the group of patients with adenoma. Platelet count was significantly higher and MPV significantly lower in the group of patients with CRC. Of all the investigated biomarkers related to the inflammation, only MPV/PC and PLR showed a statistically significant difference between the two groups, with lower values of MPV/PC and higher values of PLR in the group of patients with CRC. Despite the existence of the difference, after ROC curve analysis, none of the examined parameters showed satisfactory diagnostic accuracy for distinguishing the two groups
Examination of the possibility of thiopurine S-methyltransferase inhibition by preparations of selected plant species
No full textUpalne bolesti crijeva bolesti su koje predstavljaju globalni zdravstveni problem, a u zadnjih nekoliko desetljeća bilježi se porast njihove incidencije. Kao dva najznačajnija predstavnika ističu se Crohnova bolest i ulcerozni kolitis koje karakterizira kronična recidivirajuća upala. Tiopurin S-metiltransferaza (TPMT, E.C. 2.1.1.67) citosolni je enzim koji metabolizira reakcije S-metilacije aromatskih i heterocikličnih sulfhidrilnih skupina kao što su tiopurinski i tiopirimidinski lijekovi. Među ksenobiotike koje TPMT metabolizira spadaju i azatioprin i 6-merkaptopurin koji se u reakciji posredovanom ovim enzimom inaktiviraju. Pored konvencionalne farmakoterapije, sve više pacijenata rješenje svojih zdravstvenih problema pokušava pronaći u komplementarnoj i alternativnoj medicini. Neki od biljnih pripravaka za koje postoje znanstvene informacije o protuupalnom i imunomodulatornom učinku koji bi pozitivno utjecao na ishode liječenja ovog tipa bolesti uključuju kurkumu (Curcuma longa), crni papar (Piper nigrum), indijski tamjanovac (Boswellia serrata) i kineski androfagis (Andrographis paniculata). Cilj ovog istraživanja bio je utvrditi dovode li navedeni biljni pripravci do inhibicije tiopurin S-metiltransferaze, enzima koji je ključan u metabolizmu azatioprina i merkaptopurina, ili istodobna primjena biljnih pripravaka i navedenih lijekova ne uzrokuje takvu vrstu interakcije.
Istraživanje je uključivalo razvoj i validaciju analitičke metode koja bi učinkovito pratila enzimsku rekaciju metilacije 6-MP i nastanak 6-MMP, ispitivanje enzimske kinetike TPMT i, u konačnici, ispitivanje njegove potencijalne inhibicije ekstraktima odabranih biljnih droga. Razvijena je HPLC metoda u trajanju od 22 min. Kao nepokretna faza korištena je Cortecs Phenyl kolona (150 × 4,6 mm, veličina čestica 2,7 um). Provedena je gradijentna eluacija s dvije sastavnice mobilne faze (0,1 % mravlje kiseline u vodi, odnosno metanolu). Metoda je zadovoljila sve ispitane parametre validacije. Ispitivanje enzimske kinetike dovelo je do zaključka da TPMT dobrovoljca pokazuje visoku enzimsku aktivnost te da se dobiveni rezultati mogu translatirati na najveći udio populacije. Na kraju, određeni su i inhibicijski potencijali ekstrakata biljnih droga te su dobivene vrijednosti za ekstrakt podanka kurkume (IC50 = 275 μg/mL), ekstrakt ploda crnog papra (IC50 = 490 μg/mL), ekstrakt lista kinsekog androfagisa (IC50 = 2300 μg/mL) i smole indijskog tamjanovca (IC50 = 1900 μg/mL). No, niti jedan od ovih biljnih ekstrakata nije inhibirao TMPT učinkovito kao furosemid (IC50 = 15 μg/mL) koji je poznati inhibitor ovog enzima.
Dobiveni podaci doveli do zaključka da se koncentracije koje su u ovom istraživanju dobivene kao inhibicijske ne mogu ostvariti pri koncentracijama u kojima se odrabrani pripravci nalaze na tržištu i pokazuju svoje farmakološke učinke. Sve navedeno ukazuje da istodobna primjena ovih pripravaka i liječenja azatioprinom i 6-merkaptopurinom ne dovodi do značajnijih farmakokinetičkih interakcija zbog kojih bi istodobna primjena ovih tvari bila kontraindicirana te da, barem prema ispitivanim parametrima, ne postoji ograničenje u njihovom zajedničkom korištenju.Inflammatory bowel disease is disease that represents a global health problem, and an increase in their incidence has been recorded in the last few decades. The two most significant representatives are Crohn’s disease and ulcerative colitis, which are characterized by relapsing chronic inflammation. Thiopurine S-methyltransferase (TPMT, E.C. 2.1.1.67) is a cytosolic enzyme that metabolizes S-methylation reactions of aromatic and heterocyclic sulfhydryl groups such as thiopurine and thiopyrimidine drugs. The xenobiotics metabolized by TPMT include azathioprine and 6-mercaptopurine, which are inactivated in a reaction mediated by this enzyme. In addition to conventional pharmacotherapy, more and more patients are trying to find a solution to their health problems in complementary and alternative medicine. Some of the herbal preparations for which there is scientific information on the anti-inflammatory and immunomodulatory effect that would positively influence the treatment outcomes of this type of disease include turmeric (Curcuma longa), black pepper (Piper nigrum), Indian frankincense (Boswellia serrata) and Chinese Andrographis (Andrographis paniculata). The aim of this research was to determine whether the mentioned herbal preparations lead to the inhibition of thiopurine S-methyltransferase, an enzyme that is key in the azathioprine and mercaptopurine metabolism, or whether the simultaneous use of herbal preparations and the mentioned drugs does not cause this type of interaction.
The research included the development and validation of an analytical method that would effectively monitor the enzymatic reaction of methylation of 6MP and the formation of 6MMP, the investigation of the enzymatic kinetics of TPMT and, finally, the investigation of its potential inhibition by extracts of selected herbal drugs. An HPLC method lasting 22 min was developed. A Cortecs Phenyl column (150 × 4.6 mm, particle size 2.7 μm) was used as the stationary phase. A gradient elution with two components of the mobile phase (0.1% formic acid in water or methanol) was performed. The method met all the tested validation parameters. Examination of enzyme kinetics led to the conclusion that the volunteer’s TPMT shows high enzyme activity and that the obtained results can be translated to the largest part of the population. Finally, the inhibitory potentials of herbal drug extracts were determined, and values were obtained for turmeric root extract (IC50 = 275 μg/mL), black pepper fruit extract (IC50 = 490 μg/mL), Chinese Andrographis leaf extract (IC50 = 2300 μg /mL) and Indian frankincense resin (IC50 = 1900 μg/mL). However, none of these plant extracts inhibited TMPT as efficiently as furosemide (IC50 = 15 μg/mL), which is a known inhibitor of this enzyme.
The obtained data led to the conclusion that the concentrations obtained in this research as inhibitory cannot be achieved at the concentrations in which the selected preparations are on the market and show their pharmacological effects. All of the above indicates that the simultaneous use of these preparations and treatment with azathioprine and 6-mercaptopurine does not lead to significant pharmacokinetic interactions due to which the simultaneous use of these substances would be contraindicated and that, at least according to the tested parameters, there is no limitation in their joint use