The compound 3-quinuclidinyl benzylate (agent BZ) belongs to the group of incapacitating warfare agents with anticholinergic activity. Today, for its ability to induce functional cognitive impairment (i.e. coordination and memory disorders), the agent BZ is used mainly for scientific purposes in the study of Alzheimer's disease. Despite this fact, its pharmacokinetics has not been fully examined yet. In order to determine the agent BZ in biological material, LC-MS / MS method and sample preparation procedure for body fluids (plasma, bile) and tissues (brain, liver, kidneys) were developed, optimized and validated. The sample preparation procedure for body fluid employed solid phase extraction using a C18 column eluted with methanol and for body tissues it was precipitation with acetonitrile. The chromatographic separation was performed on Gemini NX-C18 reverse phase column (150 × 4.6 mm, 5 μm). The mobile phase consisted of a 10mM solution of ammonium acetate at pH 11 and methanol in a ratio of 30 : 70. Elution of the analytes was performed under isocratic elution. The total analysis time was 5 minutes. Mass spectrometric detection was performed by a linear ion trap using electrospray ionization. Sample preparation procedure and chromatographic analysis methods were successfully applied to real...

Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Candidate Mgr. Dimitrios Vagiannis Supervisor RNDr. Jakub Hofman, Ph.D. Title of Doctoral Thesis Study on the role of pharmacokinetic mechanisms of drug resistance in new anticancer drugs with focus on solid tumors Cancer chemotherapy is an important tool for the cure of cancer. Although the development of new anticancer drugs has been rapidly progressing, the phenomenon of multidrug resistance (MDR) continues to be a key issue leading to therapy failure in oncological patients. MDR is based on pharmacodynamic as well as pharmacokinetic mechanisms. Pharmacokinetic MDR includes drug efflux transporters and biotransformation enzymes that decrease the amount of (active form of) a drug in tumors. While the MDR role of transporters has been well understood, the participation of drug metabolizing enzymes is still unclear. This thesis investigates the role of cytochromes P450 (CYPs) in cytostatic resistance. Furthermore, it focuses on the modulation of pharmacokinetic MDR using pharmacokinetic drug-drug interactions of new targeted antitumor drugs. Finally, it aims to confirm the in vitro findings in ex vivo patient-derived tumor explants. In our latest publication, we demonstrate the significant role of...

<p>Metotreksat kao antagonista folne kiseline ima &scaron;iroku upotrebu za lečenje brojnih maligniteta, primenjen u visokim dozama i u&nbsp; kombinciji&nbsp; sa leukovorinom. Iako&nbsp; je&nbsp; terapija&nbsp; visokim&nbsp; dozama&nbsp; metotreksata drastično pobolj&scaron;ala&nbsp; prognozu pacijenata sa malignitetom, te&scaron;ki neželjeni efekti terapije predstavljaju stalan klinički problem. Ciljevi istraživanja bili su određivanje serumske koncentracije metotreksata i izračunavanje farmakokinetičkih&nbsp; parametara&nbsp; metotreksata kod dece obolele od malignih&nbsp; bolesti&nbsp; koja su na terapiji visokim dozama metotreksata (2&nbsp; g/m² i&nbsp; 5&nbsp; g/m² ); ispitivanje postojanja uticaja primenjene doze metotreksata, demografskih i kliničkih karakteristika ispitanika&nbsp; na koncentracije i farmakokinetičke parametare. Ispitivano je prisustvo i stepen kliničkih i laboratorijskih znakova toksičnosti metotreksata, kao i uticaj primenjene&nbsp; doze&nbsp; metotreksata&nbsp; i demografskih karakteristika ispitanika&nbsp; na pojavu i stepen toksičnosti . U okviru retrospektivno - prospektivne&nbsp; studije&nbsp; ukjučeno&nbsp; je&nbsp; četrdeset&nbsp; i dva pedijatrijska&nbsp; pacijenta&nbsp; uzrasta od&nbsp; 0,75 do 17,75 godina (medijana 5,75&nbsp; godina). Svi pacijenti&nbsp; su lečeni&nbsp; u&nbsp; Službi&nbsp; za&nbsp; hematologiju i&nbsp; onkologiju&nbsp; Instituta&nbsp; za&nbsp; zdravstvenu za&scaron;titu dece i omladine Vojvodine (Novi Sad, Srbija) u periodu od juna 2004. godine do juna 2012. godine. Trideset i osam ispitanika&nbsp; je lečeno pod dijagnozom akutne limfoblastne leukemije&nbsp; prema dva&nbsp; uzastopna&nbsp; protokola ALL IC - BFM 2002 i ALL IC - BFM 2009 Internacionalne&nbsp; BFM studijske&nbsp; grupe &bdquo;I - BFM - SG&ldquo;&nbsp; (International Berlin -Frankfurt - M&uuml;nster Study Group) za proučavanje i lečenje dečje non-B akutne limfoblastne leukemije. Četvoro je&nbsp; imalo&nbsp; dijagnozu non - Hodgkin limfoma&nbsp; i bili su uključen i u&nbsp; protokol NHL - BFM&nbsp; 95. Istraživanje je obuhvatilo 113 ciklusa terapije metotreksatom (1&ndash; 4 ciklusa po pacijentu) sa 386 izmerenih serumskih koncentracija metotreksata. Raspon primenjenih doza metotreksata kretao se od 800 do 10.000 mg. Koncentracije metotreksata su merene 24, 36 i 42 sata nakon započinjanja infuzije metotreksata, a po potrebi i u dužim vremenskim intervalima. Za izračunavanje farmakokinetičkih parametara kori&scaron;ćen je dvokompartmanskih farmakokinetički&nbsp; model posle obustavljanja&nbsp; intravenske&nbsp; infuzije,&nbsp; gde&nbsp; postoje relacije&nbsp; za&nbsp; farmakokinetičke&nbsp; tačke. Podaci o kliničkim i laboratorijskim znacima toksičnosti metotreksata prikupljani su iz medicinske dokumentacije, a za stepenovanje toksičnosti kori&scaron;ćen je skor sistem - Common Terminology Criteria for&nbsp; Adverse&nbsp; Events (CTCAE), Version 4.0, U.S. Department&nbsp; of&nbsp; health&nbsp; and&nbsp; human services, National Institute of Health, National Cancer Institute. U cilju utvrđivanju uticaja karakteristika ispitanika, primenjene doze i prisustva produžene eliminacije na posmatrane parametre, vr&scaron;eno je poređenje tri grupe&nbsp; pacijenata (doza 2 g/m² bez produžene eliminacije, 5 g/m² bez produžene liminacije i 5 g/m² sa produženom eliminacijom metotreksata). Za celokupnu grupu ispitanika,&nbsp; medijane&nbsp; koncentracije metotreksta&nbsp; bile&nbsp; su 25,82 &mu;mol/l u 24. satu, 0,68 &mu;mol/l u 36. satu i 0,24 &mu;mol/l u 42. satu merenja. Najizraženija interindividualna varijabilnost u koncentracijama metotreksata bila je u 42. satu merenja, dok je&nbsp; intraindividualna varijabilnost bila najizraženija u 36. satu merenja. Medijana&nbsp; klirensa&nbsp;&nbsp; metotreksata&nbsp;&nbsp; bila&nbsp; je 8,32&nbsp;&nbsp; l/h. Farmakokinetički parametri&nbsp; redom bili su:&nbsp; medijana&nbsp; volumena&nbsp; centralnog&nbsp; kompartmana V₁ 28,47&nbsp; l, medijane konstanti k₁₀ 0,206, k₁₂ 0,0245, k₂₁ 0,1114. Najizraženiji uticaj primenjene doze na koncentracije metotreksata pokazan je u 24.&nbsp; satu&nbsp; merenja, dok uticaj doze na klirens&nbsp; metotreksata nije&nbsp; pokazan. Prisustvo produžene eliminacije metotreksata dovodi do smanjenih vrednosti konstanta k₁₀ i k₂₁. Nije pokazana statistički značajna&nbsp; interakcija ispitivanih demografskih karakteristika (uzrast, telesna povr&scaron;ina i pol)&nbsp; i koncentracija metotreksata, kao ni klirensa metotreksata. Pokazana je značajna interakcija između koncentracija metotreksata i nivoa laktat dehidrogenaze, kao i klirensa metotreksata i nivoa kreatinina i laktat dehidrogenaze. Većina ispoljenih&nbsp; toksičnosti bila je umerenog stepena (&lt;3 stepena). Najzastupljeniji klinički znak toksičnosti bio je oralni mukozitis, koji je bio većeg stepena u grupi sa većom primenjenom dozom metotreksata&nbsp; (5g/m²). Najzastupljeniji&nbsp; laboratorijski toksični efekti&nbsp; metotreksata bili su leukopenija i anemija. Najteži stepeni laboratorijskih znakova toksičnosti (leukopenija, anemija, porast&nbsp; AST,&nbsp; ALT i GGT) nalazili su se u grupi sa većom dozom&nbsp; (5 g/m²) i&nbsp; sa produženom eliminacijom metotreksata. Osnov&nbsp; za&nbsp; kliničko&nbsp; vođenje&nbsp; pacijenata&nbsp; na&nbsp; terapiji visokim dozama metotreksata je terapijsko praćenje leka (therapeutic drug monitoring &ndash; TDM) zbog velikih&nbsp; interindividualnih i intraindividualnih&nbsp; varijabilnosti&nbsp; u&nbsp; farmakokinetici&nbsp; leka. Rutinsko praćenje koncentracija metotreksata važno je za identifikaciju pacijenata sa povećanim rizikom od razvoja toksičnosti ,&nbsp; te&nbsp; je TDM&nbsp; standardna&nbsp; praksa&nbsp; za smernice spasavanja leukovorinom, naročito za pacijente za koje se zna da imaju smanjen&nbsp;&nbsp; klirens metotreksata ili druge rizike povezane sa prolongiranim citotoksičnim koncentracijama (bubrežna ili jetrena o&scaron;tećenja, kolekcije tečnosti u &ldquo;trećem prostoru&rdquo;, gastrointestinalna opstrukcija). Veliki&nbsp; broj&nbsp; istraživanja&nbsp; kod pedijatrijskih pacijenata pokazao je vezu između sistemskog izlaganja metotreksatu i&nbsp; efikasnosti&nbsp; i&nbsp; toksiĉnosti&nbsp; metotreksata. Ipak, ne postoji dovoljno&nbsp; informacija o farmakokinetici metotreksata kod dece obolele od akutne limfoblastne leukemije. Takođe, ova istraživanja nisu do sada sprovođena kod dece koja su lečena u na&scaron;oj sredini.</p> / <p>Methotrexate&nbsp; is&nbsp; an&nbsp; antifolate&nbsp; drug&nbsp; widely&nbsp; used&nbsp; for&nbsp; treatment&nbsp; of&nbsp; various malignant&nbsp; tumours.&nbsp; It&nbsp; is&nbsp; used&nbsp; at&nbsp; high&nbsp; doses&nbsp; and&nbsp; in&nbsp; combination&nbsp; with leucovorin rescue.&nbsp; Although&nbsp; high - dose&nbsp; MTX&nbsp; therapy&nbsp; dramatically&nbsp; improves&nbsp; the&nbsp; prognosis&nbsp; of patients with malignancies, severe adverse events are constant clinical concern. The&nbsp; aims&nbsp; of&nbsp; this&nbsp; stydy&nbsp; were&nbsp; to&nbsp; determine&nbsp; the&nbsp; serum&nbsp; concentration&nbsp; of&nbsp; methotrexate&nbsp; and&nbsp; to&nbsp; calculate&nbsp; the&nbsp; pharmacokinetic&nbsp; parameters&nbsp; of&nbsp; methotrexate&nbsp; in children&nbsp; suffering&nbsp; from&nbsp; malignant&nbsp; deseases&nbsp; who&nbsp; are&nbsp; treated&nbsp; with&nbsp; high&nbsp; doses&nbsp; of metotrexate&nbsp; (2&nbsp; g/m² i&nbsp; 5&nbsp; g/m² );&nbsp; furthermore,&nbsp; to&nbsp; investigate&nbsp; the&nbsp; effects&nbsp; of&nbsp; the&nbsp; applied doses of methotrexate, and demographic and clinical characteristics of the examinees on&nbsp;&nbsp; the&nbsp;&nbsp; concentration&nbsp;&nbsp; and&nbsp;&nbsp; pharmacokinetic&nbsp;&nbsp; parameters&nbsp;&nbsp; of&nbsp;&nbsp; the&nbsp;&nbsp; drug.&nbsp;&nbsp; The&nbsp;&nbsp; study investigated the&nbsp;&nbsp; presence&nbsp;&nbsp; and&nbsp;&nbsp; the&nbsp;&nbsp; degree&nbsp;&nbsp; of&nbsp;&nbsp; clinical&nbsp;&nbsp; and&nbsp;&nbsp; laboratory&nbsp;&nbsp; signs&nbsp;&nbsp; of metotrexate&nbsp; toxicity,&nbsp; as&nbsp; well&nbsp; as&nbsp; the&nbsp; effect&nbsp; of&nbsp; the&nbsp; applied&nbsp; doses,&nbsp; and&nbsp; demographic characteristics of the examinees on the appearance and the degree of toxicity. The retrospective - prospective study included 42&nbsp; pediatric patients aged from 0.75&nbsp; to&nbsp; 17.75&nbsp; years&nbsp; (median&nbsp; 5.75&nbsp; years).&nbsp; All&nbsp; patients&nbsp; were&nbsp; threated&nbsp; at&nbsp; the&nbsp; Children and Youth Health Care Institute of Vojvodina (Novi Sad, Serbia), Hemathology and Oncology&nbsp; Section,&nbsp; in&nbsp; the&nbsp; period&nbsp; from&nbsp; June&nbsp; 20 04&nbsp; to&nbsp; June&nbsp; 2012.&nbsp; 38&nbsp; examinees diagnosed as acute lymphoblastic leukemia were treated according to two subsequent protocols,&nbsp; ALL&nbsp; IC - BFM&nbsp; 2002&nbsp; and&nbsp; ALL&nbsp; IC - BFM&nbsp; 2009&nbsp; of&nbsp; the&nbsp; International&nbsp; BFM study&nbsp; group &bdquo;I - BFM - SG&ldquo; (International Berlin - Frankfurt - M&uuml;nster&nbsp; Study&nbsp; Group)&nbsp; for management&nbsp;&nbsp; of&nbsp;&nbsp; childhood&nbsp;&nbsp; non - B&nbsp;&nbsp; acute&nbsp;&nbsp; lymphoblastic&nbsp;&nbsp; leukemia.&nbsp;&nbsp; 4&nbsp;&nbsp; examinees diagnosed&nbsp; as&nbsp; non - Hodgkin&nbsp; lymphoma&nbsp; were&nbsp; treated&nbsp; according&nbsp; to&nbsp; the&nbsp; NHL - BFM&nbsp; 95 protocol. The study included 113 cycles of therapy with methotrexate (1-4 cycles per patient)&nbsp; with&nbsp; 3 86&nbsp; measured&nbsp; serum&nbsp; concentrations&nbsp; of&nbsp; methotrexate.&nbsp; The&nbsp; range&nbsp; of&nbsp; the applied doses was between 800 and 10,000 mg. The&nbsp; concentration&nbsp; of&nbsp; methotrexate&nbsp; was&nbsp; measured&nbsp; 24,&nbsp; 36&nbsp; and&nbsp; 42&nbsp; hours&nbsp; after the initiation of the methotrexate infusion, as well as in longer time intervals when needed.&nbsp; To&nbsp; calculate&nbsp; the&nbsp; pharmacokinetic&nbsp; parameters,&nbsp; the&nbsp; study&nbsp; applied&nbsp; the&nbsp; two - compartment&nbsp; pharmacokinetic&nbsp; model&nbsp; after&nbsp; the&nbsp; termination&nbsp; of&nbsp; intravenous&nbsp; infusion, when&nbsp; relations&nbsp; for&nbsp; pharmacokinetic&nbsp; points&nbsp; existed.&nbsp; Data&nbsp; on&nbsp; clinical&nbsp; and&nbsp; laboratory signs of methotrexate toxicity were collected&nbsp; from medical documentation, and the Common&nbsp; Terminology&nbsp; Criteria&nbsp; for&nbsp; Adverse&nbsp; Events&nbsp; (CTCAE),&nbsp; Version&nbsp; 4.0,&nbsp; U.S. Department&nbsp; of&nbsp; health&nbsp; and&nbsp; human&nbsp; services,&nbsp; National&nbsp; Institute&nbsp; of&nbsp; Health,&nbsp; National Cancer&nbsp; Institute, was&nbsp; used&nbsp; as&nbsp; the&nbsp; score&nbsp; system&nbsp; for&nbsp; toxicity&nbsp; ranking.&nbsp; In&nbsp; order&nbsp; to determine&nbsp; the&nbsp; effects&nbsp; of&nbsp; the examinees&rsquo;&nbsp; characteristics, applied&nbsp; doses&nbsp; and&nbsp; the presence&nbsp; of&nbsp; prolonged&nbsp; elimination on&nbsp; the&nbsp; parameters&nbsp; of&nbsp; interest,&nbsp; three&nbsp; groups&nbsp; of patients were&nbsp; compared (2 g/m² dose without prolonged elimination, 5 g/m² without prolonged elimination and 5 g/m² with prolonged elimination of methotrexate). In the&nbsp; entire&nbsp; group of&nbsp; examinees, the median&nbsp; concentration of methotrexate was&nbsp; 25.82 &mu;mol/l in the 24th hour, 0.68 &mu;mol/l in the 36th&nbsp; hour&nbsp; and 0.24 &mu;mol/l in the 42nd hour of&nbsp; observation. The largest inter - individual variability of methotrexate concentration&nbsp; was&nbsp; observed&nbsp; in&nbsp; the&nbsp; 24th&nbsp; hour&nbsp; while&nbsp; the&nbsp; largest&nbsp; intra - individual variability&nbsp; was&nbsp; recorded&nbsp; in&nbsp; the&nbsp; 36th&nbsp; hour&nbsp; of&nbsp; observation.&nbsp; The&nbsp; median&nbsp; clearance&nbsp; of methotrexate&nbsp; was&nbsp; 8.32l/h.&nbsp; Pharmacokinetic&nbsp; parameters&nbsp; were&nbsp; the&nbsp; following:&nbsp; median volume&nbsp; of&nbsp; the&nbsp; central&nbsp; compartment V₁ 28.47&nbsp; l,&nbsp; median&nbsp; constants k₁₀ 0,206, k₁₂ 0,0245, k₂₁ 0,1114, respectively. The&nbsp;&nbsp; strongest&nbsp;&nbsp; influence&nbsp;&nbsp; of&nbsp;&nbsp; the&nbsp;&nbsp; applied&nbsp;&nbsp; dose&nbsp;&nbsp; on&nbsp;&nbsp; the&nbsp;&nbsp; methotrexate concentration was recorded in the 24th hour of observation while no influence on the methotrexate&nbsp; clearance&nbsp; was&nbsp; found.&nbsp; The&nbsp; presence&nbsp; of&nbsp; prolonged&nbsp; elimination&nbsp; of methotrexate&nbsp;&nbsp; causes&nbsp;&nbsp; lower&nbsp; constants k₁₀ and&nbsp;&nbsp; k₂₁. There&nbsp;&nbsp; was&nbsp;&nbsp; no&nbsp;&nbsp; statistically significant&nbsp; interaction&nbsp; between&nbsp; the&nbsp; investigated&nbsp; demographic&nbsp; characteristics&nbsp; (age, body&nbsp; surface&nbsp; and&nbsp; gender)&nbsp; and&nbsp; the&nbsp; methotrexate&nbsp; concentration,&nbsp; nor&nbsp; between&nbsp; the demographic&nbsp;&nbsp; characteristics&nbsp;&nbsp; and&nbsp;&nbsp; the&nbsp;&nbsp; methotrexate&nbsp;&nbsp; clearance.&nbsp;&nbsp; A&nbsp;&nbsp; significant interaction was found between methotrexate concentration and lactat dehydrogenase level, as&nbsp;&nbsp; well&nbsp;&nbsp; as&nbsp;&nbsp; between&nbsp;&nbsp; methotrexate&nbsp;&nbsp; clearance&nbsp;&nbsp; and&nbsp;&nbsp; creatinine&nbsp;&nbsp; and&nbsp;&nbsp; lactate dehydrogenase level, respectively. Most of the observed toxicities were of moderate degree (&lt; 3 degrees). Oral mucositis&nbsp; was&nbsp; the&nbsp; most&nbsp; represented&nbsp; clinical&nbsp; sign&nbsp; of&nbsp; toxicity,&nbsp; and&nbsp; it&nbsp; was&nbsp; of&nbsp; higher degree&nbsp; in&nbsp; the&nbsp; group&nbsp; where&nbsp; the&nbsp; applied&nbsp; dose&nbsp; of&nbsp; methotrexate&nbsp; was&nbsp; higher&nbsp; (5&nbsp; g/m² ). Leucopenia&nbsp; and&nbsp; anemia&nbsp; were&nbsp; the&nbsp; most&nbsp; represented&nbsp; laboratory&nbsp; toxic&nbsp; effects.&nbsp; The most severe laboratory signs of toxicity&nbsp; (leucopenia, anemia, increase in AST, ALT and&nbsp; GGT&nbsp; activity)&nbsp; were&nbsp; observed&nbsp; in&nbsp; the&nbsp; group&nbsp; with&nbsp; the&nbsp; higher&nbsp; dose&nbsp; (5&nbsp; g/m² )&nbsp; and prolonged methotrexate elimination. Due to high inter- and&nbsp;&nbsp; intra-individual&nbsp;&nbsp;&nbsp; variability&nbsp; of&nbsp; the drug pharmacokinetics,&nbsp; the&nbsp; basis&nbsp; for&nbsp; the&nbsp; clinical&nbsp; care&nbsp; of&nbsp; patients&nbsp; on&nbsp; high&nbsp; methotrexate dosage&nbsp; therapy&nbsp; is&nbsp; therapeutic&nbsp; drug&nbsp; monitoring &ndash; TDM.&nbsp; Routine&nbsp; monitoring&nbsp; of methotrexate serum concentration is important for the identification of patients with a high&nbsp; risk&nbsp; of&nbsp; toxicity,&nbsp; and&nbsp; thus&nbsp; TDM&nbsp; is&nbsp; used&nbsp; as&nbsp; a&nbsp; standard&nbsp; procedure&nbsp; which&nbsp; provides guidelines&nbsp; for&nbsp; leucovorin&nbsp; rescue,&nbsp; particularly&nbsp; for&nbsp; patients&nbsp; with&nbsp; a&nbsp; lower&nbsp; methotrexate clearance or other risks associated with prolonged cytotoxic concent rations (kidney or liver&nbsp; damage,&nbsp; body&nbsp; fluid&nbsp; accumulation&nbsp; in&nbsp; the&nbsp; &ldquo;third&nbsp; space&rdquo;,&nbsp; gastrointestinal obstruction). Numerous studies involving pediatric patients have documented the link between&nbsp; a&nbsp; systemic&nbsp; methotrexate&nbsp; exposure&nbsp; on&nbsp; one&nbsp; hand,&nbsp; and&nbsp; the&nbsp; efficiency&nbsp; and toxicity of&nbsp; ethotrexate on the other hand. However, there is no sufficient data on the methotrexate&nbsp;&nbsp;&nbsp; pharmacokinetics&nbsp;&nbsp; in&nbsp;&nbsp; children&nbsp;&nbsp; suffering&nbsp;&nbsp; from&nbsp;&nbsp; acute&nbsp;&nbsp; lymphoblastic leukemia.&nbsp;&nbsp; Moreover,&nbsp;&nbsp; this&nbsp;&nbsp; type&nbsp;&nbsp; of&nbsp;&nbsp; research,&nbsp;&nbsp; involving&nbsp;&nbsp; children&nbsp;&nbsp; treated&nbsp;&nbsp; in&nbsp;&nbsp; the geographical region of this study, have not been conducted.</p>

6 Pharmacokinetics of Intramuscularly Administered Thermoresponsive Polyacrylamides Author: Ondřej Groborz Supervisor: doc. Mgr. Martin Hrubý, Ph.D., DSc. Institute of Macromolecular Chemistry, Czech Academy of Sciences Advisers: Ing. Pavel Švec RNDr. Lenka Loukotová, PhD. Abstract Polymer solutions with lower critical solution temperature (LCST) undergo a phase separation when heated above their cloud point temperature (TCP). These thermoresponsive polymers have numerous promising medicinal applications, such as in situ depot-forming radiotherapy (brachytherapy), controlled drug-release, immuno-radiotherapy, injectable thermogelling for tissue engineering and cell culture and magnetic resonance imaging (MRI), among others. Yet, despite extensive research on medicinal applications of thermoresponsive polymers, their fate after their administration remains largely unknown. Thus, in our study, we synthesized and thoroughly characterized four different thermoresponsive polyacrylamides, namely poly(N-(2,2-difluoroethyl)acrylamide), poly(N- isopropylacrylamide), poly(N,N-diethylacrylamide) and poly(N-acryloylpyrrolidine) under physiologically relevant conditions. Subsequently, we determined their biodistribution kinetics in mice and proposed a data-based pharmacological model to describe their in vivo behaviour,...

5-nitrofuraldehido darinių antimikrobinio aktyvumo tyrimas, toksiškumo, farmakokinetinių savybių ir struktūros aktyvumo ryšio įvertinimas. K. Gaivelytės magistro baigiamasis darbas. Moksliniai vadovai: dr. V. Petrikaitė, dr. J. Šarlauskas, prof. habil. dr. A. Pavilonis; Kauno medicinos universiteto, Farmacijos fakulteto, Vaistų chemijos katedra. Kaunas, 2010. Darbo tikslas – įvertinti 5-nitrofuraldehido darinių struktūros įtaką jų antimikrobiniam aktyvumui ir parinkti perspektyviausius antimikrobinius junginius tolimesniems tyrimams. Tyrimo metodai. Junginių antimikrobinio aktyvumo prognozė atlikta panaudojant PASS programą. Antimikrobinis aktyvumas ištirtas in vitro serijinio skiedimo standžioje terpėje metodu. Junginių farmakokinetinių savybių ir toksiškumo prognozė atlikta, panaudojant ADME/Tox Boxes programą. Tyrimo rezultatai. PASS programa antibakterinį ir priešgrybelinį aktyvumą prognozavo visiems tiriamiems junginiams. Atlikus tyrimus in vitro, nustatyta, kad junginių aktyvumas prieš įvairius mikroorganizmus skyrėsi, nitrofurano fragmento neturintys junginiai buvo visai neaktyvūs. Nitrofurano bisdariniai yra gana aktyvūs prieš visas bakterijas (MSK = 0,5 100 μg/ml), išskyrus P. aeruginosa, K. pneumoniae ir P. mirabilis. Bisjunginys BIC-34, turintis butilo fragmentą, buvo aktyviausias prieš S. aureus, E. faecalis ir B. subtilis, o piridino liekaną turintis bisjunginys BIC 67 – prieš K. pneumoniae, P. aeruginosa, P. mirabilis (MSK = 50 μg/ml). Gali būti, kad šio... [toliau žr. visą tekstą] / Analysis of 5-nitrofuraldehyde derivatives antimicrobial activity, evaluation of toxicity, pharmacokinetic properties and structure – activity relationship. K. Gaivelytė Master Thesis. Scientific supervisors: Dr. V. Petrikaitė, Dr. J. Šarlauskas, Prof. Habil. Dr. A. Pavilonis; Kaunas University of Medicine, Faculty of Pharmacy, Department of Medicinal Chemistry. Kaunas, 2010. The Aim of the Research – to evaluate the influence of the structure of 5-nitrofuraldehyde derivatives and identify the most promising compounds for the further research. Methods. Prognosis of antimicrobial activity of all compounds was carried out by using PASS software. Antimicrobial activity was tested in vitro by using a serial dilution in agar technique. Pharmacokinetic properties and toxicity were predicted by using ADME/Tox Boxes program. Results. PASS program predicted antibacterial and antifungal activity for all tested compounds. The results of experiments in vitro showed that activity against various microorganisms was different; compounds without nitrofuran fragment were not active. Biscompouds were active enough against all bacteria (MIC = 0,5-100 μg/ml), except P. aeruginosa, K. pneumoniae and P. mirabilis. Biscompoud possessing butyl fragment in its structure was the most active against S. aureus, E. faecalis and B. subtilis and biscompound BIC-67 with the moiety of pyridine was the most active against K. pneumoniae, P. aeruginosa, P. mirabilis (MIC = 50 μg/ml). It could be that the... [to full text]

Objective of the work: The purpose of this quantitative retrospective comparative study was to register possible cases of augmentedted renal clearance (ARC) in patients of Hospital of Lithuanian University of Health Sciences and analyse the differences in assessments of cases of Augmented Renal Clearance and the drug therapy problems related to ARC. Tasks: To achieve the objective, several tasks were performed: 1) to register possible ARC patients cases as assessed by Cocroft-Gault and their possible associated reasons; 2) to analyse differences in three equations used for GFR estimation: Cocroft-Gault, MDRD simplified, and CKD-EPI. 3) compare the therapies of the patients and determine the drugs that are in risk of being underdosed when ARC is present. Methodology: An ARC survey (appendix 1) was filled about patients from various departments of Clinics during the period of 2013 03 04 – 2014 08 15. All patients were selected according serum creatinine values that were 50 µmol/l. or less. Two goups of patients were assigned for analysis: patients were grouped according Cocroft - Gault creatinine clearance values: (1) ARC group A CrCl >130 ml./min and (2) comparative Non-ARC group B CrCl 90-130 ml./min. Data were analyzed by using descriptive and comparative statistical analysis, considering statistically significant difference between the groups if p value was <0.05. Results and conclusions: 1. In the research group and comparative groups were 31 patients selected... [to full text] / Darbo tikslas: Šio kiekybinio retrospektyvaus palyginamojo darbo tikslas buvo surinkti duomenis apie padidinto inkstų klirenso PIK atvejus Lietuvos sveikatos mokslų universiteto ligonines Kauno klinikose. Buvo siekiama išanalizuoti sirtumus tarp skirtingų PIK įvertinimo būdų ir įvertinti galimas su PIK susijusias terapijos problemas. Uždaviniai: norint pasiekti užsibrėžtus tikslus šie uždaviniai buvo iškelti: 1) užregistruoti PIK atvejus ir nustatyti jų galimas priežastis. 2) apskaičiuoti GFG trimis skirtingomis formulėmis (Cocroft-Gault, MDRD, CKD-EPI) ir išanalizuoti skirtumus. 3) palyginti pacientų terapijas ir nustatyti, kurie vaistai galimai yra subterapinio dozavimo rizikoje Metodika: PIK anketa ( 1 priedas) buvo pildoma apie pacientus iš skirtingų Kauno klinikų skyrių, laikotarpiu nuo 2013 03 04 iki 2014 08 15. Visi pacientai buvo parinkti pagal kreatinino kiekį serume – 50 μmol/l.. ir mažiau. Dvi pacientų grupės buvo parinktos analizei: pacientai buvo sugrupuoti pagal kreatinino klirensą į (1) PIK A grupę – CrCl > 130 ml./min. ir (2) palyginamąją B grupę – CrCl 90-130 ml./min. Duomenys buvo analizuojami naudojant palyginamąją ir aprašomąją statistiką. Skirtumai tarp grupių buvo laikomi statistiškai reikšmingi, kai p reikšmė buvo <0.05. Rezultatai ir išvados: 1. Abiejose grupėse buvo surinkta po 31 pacientą (iš viso 62 pacientai). Remiantis darbo rezultatais, galima daryti išvadą, kad PIK (kai GFG yra 130ml/min. ir daugiau) nustatymui naudojant Cocroft-Gault formulę... [toliau žr. visą tekstą]

In recent years, the focus on augmented renal clearance increased as it was found by other researchers to result in subtherapeutic drug dosing concentrations. Accurate assessment of renal function is important for prescribing optimal dosis of pharmaceuticals for ARC patients. Objective of the work: The purpose of this quantitative retrospective comparative study was to register possible cases of Accelerated renal clearance in patients of Hospital of Lithuanian University of Health Sciences Kaunas Clinics and analyse the differences in assessments of cases of Augmented Renal Clearance and the possible risks of ARC for therapy. Tasks: To achieve the objective several tasks were raised: 1) to register possible ARC patients cases as assessed by Cocroft-Gault and their possible associated reasons; 2) to analyse differences in three for GFR estimation used equations (Cocroft-Gault, MDRD simplified, and CKD-EPI). 3) determine the risk drugs for changed renal elimination. Methodology: ARC survey (appendix 1) was filled about patients from various departments of Clinics during the period of 2013 03-04 – 2013 12-20. All patients were selected according serum creatinine values that were 50 µmol/l. or less. Two goups of patients were assigned for analysis: patients were grouped according Cocroft - Gault creatinine clearance values: (1) ARC group A CrCl >130 ml./min and (2) comparative Non-ARC group B CrCl 90-130 ml./min. In the group A were 31 and in the group B - 5 patients... [to full text] / Pastaraisiais metais labai išaugo tyrimų apie padidintą inkstų klirensą (PIK), nes pagal keleto tyrejų duomenis šios būklės pasekmė yra subterapinės vaistų koncentracijos. Tikslus inkstų funkcijos nustatymas yra labai svarbus norint parinkti optimalias terapines vaistų dozes padidinto inkstų klirenso pacientams. Darbo tikslas: Šio kiekybinio retrospektyvaus palyginamojo darbo tikslas buvo surinkti duomenis apie padidinto inkstų klirenso PIK atvejus Lietuvos sveikatos mokslų universiteto ligonines Kauno klinikose. Buvo siekiama išanalizuoti sirtumus tarp skirtingų PIK įvertinimo būdų ir įvertinti galimas PIK rizikas terapijai Uždaviniai: norint pasiekti užsibrėžtus tikslus šie uždaviniai buvo iškelti: 1) užregistruoti PIK atvejus ir nustatyti jų galimas priežastis. 2) apskaičiuoti GFG trimis skirtingomis formulėmis (Cocroft-Gault, MDRD, CKD-EPI) ir išanalizuoti skirtumus. 3) nustatyti vaistus, kurie gali būti pakitusios inksų eliminacijos rizikoje. Metodika: PIK anketa ( 1 priedas) buvo pildoma apie pacientus iš skirtingų Kauno klinikų skyrių, laikotarpiu nuo 2013 04 03 iki 2013 12 20. Visi pacientai buvo parinkti pagal kreatinino kiekį serume – 50 µmol/l.. ir mažiau. Dvi pacientų grupės buvo parinktos analizei: pacientai buvo sugrupuoti pagal kreatinino klirensą į (1) PIK A grupę – CrCl > 130 ml./min. ir (2) palyginamąją B grupę – CrCl 90-130 ml./min. A grupėje buvo parinktas 31 pacientas ir B grupėje 5 pacientai. Rezultatai: Vidutinės GFG reikšmės tiriamojoje... [toliau žr. visą tekstą]

This thesis describes in the form of a commentary on own original publications research on the problems of cannabinoids, ie. phytocannabinoids and some synthetic cannabinoids, their pharmacokinetics and effects. The work consists of four thematic areas: the pharmacokinetics of delta-9- tetrahydrocannabinol (THC) and cannabidiol (CBD) in rats, depending on the route of administration; THC concentration time profile in humans (after inhalation) and implications for transport safety; the pharmacokinetic profile of synthetic cannabinoids in rats; extraction and determination of phytocannabinoids in plant material. The first part of the thesis was to determine pharmacokinetic profiles of THC, CBD and combination thereof (1:1 weight ratio) in rats with respect to administration common in humans, i.e. inhalation, oral and subcutaneous administration. THC, its metabolites (11-hydroxy-tetrahydrocannabinol, 11-OH-THC; 11-nor-delta-9- carboxytetrahydrocannabinol, THCOOH) and CBD concentrations in serum and brains of animals were monitored at the 24 hours experimental interval during the study. Except for inhalation administration, co-administration of CBD inhibited THC metabolism (after both oral and subcutaneous), resulting in an increase in THC concentrations in both serum and brain of the rats relative to...

<p>Interindividualne razlike u sastavu i aktivnosti crevne mikroflore mogu uticati na metabolizam lekova kao i na njihov konačan terapijski odgovor. Simvastatin je lek iz grupe statina i karakteri&scaron;e ga izuzetno mala rastvorljivost u vodi, mala bioraspoloživost (&lt;5%) i velike interindividualne razlike u terapijskom odgovoru čiji uzroci nisu u potpunosti obja&scaron;njeni. Poslednjih godina velika pažnja se posvećuje ispitivanjima žučnih kiselina u razvoju novih farmaceutskih formulacija zbog svoje uloge u solubilizaciji i modifikaciji prodora lekova kroz biolo&scaron;ke membrane. Zbog svega navedenog, u fokusu na&scaron;eg istraživanja su bile potencijalne interakcije između simvastatina, probiotskih bakterija i žučnih kiselina o kojima se vrlo malo zna, a od izuzetne su važnosti, zbog mogućeg uticaja na farmakokinetske i farmakodinamske osobine simvastatina, pa samim tim i na konačan terapijski odgovor kod pacijenta.Cilj istraživanja je bio da se ispita prodor i metabolizam simvastatina u probiotskim bakterijama kao i uticaj različitih žučnih kiselina na transport ovog leka u bakterijske ćelije. Takođe, cilj je bio da se ispita uticaj soli žučnih kiselina na distribucioni koeficijent simvastatina, kao i interakcije žučnih kiselina sa simvastatinom na nivou transportnih proteina probiotskih bakterija kako bi se objasnila priroda očekivanih interakcija.Identifikacija i kvantifikacija uzoraka vr&scaron;ena je metodom tečne hromatografije sa masenom spektrometrijom (LC-MS/MS). Kori&scaron;ćenjem programskih paketa VolSurf+ i Molinspiration, za identifikovane metabolite su izračunati molekulski deskriptori koji opisuju fizičko-hemijske i farmakokinetske osobine molekula. Određivanje distribucionog koeficijenta vr&scaron;eno je Shake-flask metodom. Interakcije žučnih kiselina sa simvastatinom na nivou transportnih proteina probiotskih bakterija ispitane su doking studijama pomoću SwissDock programa. Prilikom dvadesetčetvoročasovne inkubacije sa probiotskim bakterijama uočen je statistički značajan pad koncentracije simvastatina u ekstracelularnom sadržaju. Ukupan sadržaj simvastatina, kao zbir ekstracelulamog i intracelularnog sadržaja, je tokom čitavog ispitivanog perioda bio statistički značajno niži u odnosu na kontrolnu grupu bez probiotika navodeći na zaključak da se deo simvastatina tokom vremena metabolisao pod dejstvom enzima ispitivanih bakterija. Detektovano je i identifikovano 8 metaboličkih produkata simvastatina. Na osnovu izračunatih vrednosti molekulskih deskriptora, očekuje se da će metabolit M-452, koji predstavlja hidroksilovani produkt simvastatinske kiseline, pokazati najbolje rezultate u pogledu fizičko-hemijskih osobina i bioraspoloživosti u biolo&scaron;kom sistemu. Žučne kiseline nisu dovele do statistički značajne modifikacije transporta simvastatina u/iz probiotskih bakterija. Ipak, u nekim vremenskim tačkama primećena je ne&scaron;to veća koncentracija leka u ekstracelulamom prostoru u grupama sa žučnim kiselinama. Ove razlike se mogu delimično objasniti rezultatima određivanja distribucionog koeficijenta koji su pokazali da ispitivane žučne kiseline dovode do statistički značajnog smanjenja distribucionog koeficijenta simvastatina usled povećanja rastvorljivosti u vodenoj fazi. Rezultatima doking studija procenjeno je da ispitivane žučne kiseline imaju veći afinitet prema čak 80% multidrug transportera ispitivanih bakterija u odnosu na simvastatin &scaron;to govori o mogućnosti ostvarivanja interakcija žučnih kiselina sa ovim lekom na nivou transportnih proteina probiotskih bakterija. Na osnovu dobijenih rezultata možemo zaključiti da probiotske bakterije imaju ogroman uticaj na sudbinu simvastatina u biolo&scaron;kom sistemu. Uzimajući u obzir činjenicu da probiotske bakterije ulaze u sastav normalne crevne flore i da svaki organizam poseduje specifičan bakterijski sastav, trebalo bi posvetiti vi&scaron;e pažnje ispitivanju njegovog uticaja na farmakokinetiku lekova. Neophodna su dalja in vivo ispitivanja kako bi se utvrdila potencijalna farmakolo&scaron;ka aktivnost identifikovanih metabolita simvastatina nastalih pod dejstvom enzimske aktivnosti probiotskih bakterija. Povećanje rastvorljivosti simvastatina pomoću žučnih kiselina otvara mogućnost za dalja istraživanja u cilju razvoja novih farmaceutskih formulacija sa pobolj&scaron;anom bioraspoloživosti i farmakokinetskim osobinama.</p> / <p>Interindividual differences in the composition and activity of the gut microflora may affect the metabolism of drugs as well as their final therapeutic response. Simvastatin is drug from the group of statins and has extremely low water solubility, low bioavailability (&lt;5%) and high interindividual differences in therapeutic response whose causes are not fully understood. In recent years, great attention has been paid to studies of bile acids in the development of new pharmaceutical formulations because of their role in the drug solubilization and modification of drug transport through biological membranes. Accordingly, interactions between simvastatin, probiotic bacteria and bile acids were the focus of our research due to great importance and potential influence on the pharmacokinetic and pharmacodynamic properties of simvastatin, and therefore the final therapeutic response in the patients. The aim of the study was to investigate the simvastatin transport and metabolism in probiotic bacteria as well as the effect of various bile acids on drug transport into the bacterial cell. Additonally, the aim was to investigate the influence of bile salts on the distribution coefficient of simvastatin, and the interactions of bile acids with simvastatin at the level of probiotic transport proteins in order to elucidate the nature of expected interactions. Identification and quantification of samples were performed with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Molecular descriptors that describe the physico-chemical and pharmacokinetic properties of identified metabolites were calculated using the software packages VolSurf+ and Molinspiration. Determination of the distribution coefficient was performed using Shake-flask method. Interaction of bile acids with simvastatin at the level of bacterial transport proteins were studied using docking studies with SwissDock program. During the twenty-four hours of incubation with probiotic bacteria, simvastatin concentrations in the extracellular contet showed a statistically significant decrease. The total amount of simvastatin, as the sum of the extracellular and intracellular amount, during the whole study period, was significantly lower in comparison with control group without probiotics, suggesting that the part of simvastatin was metabolized by the enzymatic activity of studied bacteria. Accordingly, eight metabolic products of simvastatin were detected and identified. Based on the calculated values of molecular descriptors, it is expected that the metabolite M-452, which is the hydroxylated product of simvastatin acid, will show the best results in terms of physico-chemical properties and bioavailability in biological system. Bile acids did not show a significant influence on simvastatin transport into probiotic bacteria. However, in some time points, slightly higher drug concentrations in the extracellular medium in groups with bile acids were observed. These differences can be partly explained by the results of the determination of the distribution coefficients which showed that investigated bile acids lead to a statistically significant decrease in simvastatin distribution coefficient due to increased solubility in the aqueous phase. The results of docking studies estimated that studied bile acids have stronger affinities for the 80% of bacterial multidrug transporters compared to simvastatin indicating the possibility of achieving the interactions of bile acids with simvastatin at the level of transport proteins of probiotic bacteria. Based on the obtained results it could be concluded that probiotic bacteria have great influence on the fate of simvastatin in a biological system. Taking into account the fact that probiotic bacteria are the normal part of gut microflora and that each individual has specific bacterial fingerprint, more attention should be paid on studying its influence on drug pharmakocinetics. Further in vivo studies are required in order to determine potential pharmacological activity of identified simvastatin metabolites. Increased water solubility of simvastatin with bile acids may open the possibility for further investigations with the aim of development of new pharmaceutical formulation with improved bioavailability and pharmacokinetic properties.</p>

<p style="text-align: justify;">Reverzno-faznom tečnom hromatografijom pod visokim pritiskom primenom dva sistema<br />rastvarača ispitano je pona&scaron;anje i hromatografska lipofilnost prirodnih stiril laktona 7-(+)-<br />goniofufurona, 7-epi-(+)-goniofufurona, krasalaktona B i C i dvadeset njihovih<br />novosintetizovanih derivata i analoga. U ranijim ispitivanjima pokazalo se da ova jedinjenja<br />imaju veliki biolo&scaron;ki potencijal jer pokazuju zapaženu citotoksičnost prema vi&scaron;e humanih<br />tumorskih ćelijskih linija. Hromatografsko pona&scaron;anje jedinjenja uglavnom je u skladu sa<br />njihovom strukturom. Ustanovljene su linearne veze između hromatografskih retencionih<br />konstanti i većine in silico parametara lipofilnosti. Primenom hemometrijske QSRR analize<br />utvrđeni su veoma dobri multi linearni regresioni prediktivni modeli kvantitativne zavisnosti<br />između eksperimentalno dobijene hromatografske retencione konstante, koja defini&scaron;e<br />retenciju jedinjenja u čistoj vodi i in silico molekulskih deskriptora odnosno strukture<br />jedinjenja. Lipofilnost jedinjenja ima najveći uticaj na njihove farmakokinetičke, tj. ADME<br />(apsorpcija, distribucija, metabolizam, eliminacija) osobine. Definisani su i statistički<br />potvrđeni najbolji multi linearni regresioni modeli zavisnosti farmakokinetičkih parametara<br />stiril laktona i od drugih molekulskih deskriptora. In vitro citotoksična aktivnost jedinjenja<br />evaluirana je prema četiri nove humane maligne ćelijske linije: kancer prostate (PC3), kancer debelog creva (HT-29), melanom (Hs294T), adenokancer pluća (A549). Najaktivnije<br />novosintetizovano jedinjenje je triciklični 4-fluorocinamatni analog, koji ispoljava<br />nanomolarnu aktivnost (IC₅₀ 2,1 nM) prema ćelijama melanoma i aktivniji je preko 2250 puta od komercijalnog antitumorskog agensa doksorubicina (DOX). SAR analizom utvrđena je zavisnost između strukture i biolo&scaron;ke aktivnosti jedinjenja. Molekulskim dokingom ispitana je veza stiril laktona i ciljanog proteina značajnog za kancer prostate. Jedinjenja sa visokom inhibitornom aktivno&scaron;ću prema ćelijama kancera prostate imaju visok doking skor i mogu graditi koordinativno-kovalentnu vezu sa Fe²+jonom prisutnim u aktivnom centru enzima. 3D-QSAR analizom, koja je izvedena metodama komparativnih polja CoMFA i CoMSIA, formiran je značajan prediktivni model između hemijske strukture i biolo&scaron;ke aktivnosti stiril laktona.</p> / <p>The behavior and the chromatographic lipophilicity natural styryl lactone 7-(+)-<br />goniofufurone, 7-epi-(+)-goniofufurone, crassalactones B and C and twenty of their newly<br />synthesized derivatives and analogs were examined using reverse-phase high performance liquid chromatography in the two solvent systems. In previous studies it has been shown that these compounds have great biological potential toward several human tumor cell lines. Chromatographic behavior of the compounds is generally in accordance with their structure. The relationships between the chromatographic retention constants and the majority of their in silico lipophilicity parameters are linear. The application of chemometric QSRR analysis determined very good multiple linear regression predictive models of quantitative correlation between experimentally obtained chromatographic retention constant, which determines the retention of the compound in pure water and in silico molecular descriptors, i.e. the structure of the compound. The lipophilicity of the compounds has a major influence on their pharmacokinetics, i.e. ADME (absorption, distribution, metabolism, elimination) properties. The best multi-linear regression models depending on the pharmacokinetic parameters of styryl lactone and other molecular descriptors have been defined and statistically validated. In vitro cytotoxic activity of the compounds was evaluated according to four novel human malignant cell lines: prostate cancer (PC3), colon cancer (HT-29), melanoma (Hs294T), lung adenocarcinom (A549). The most active compound was tricyclic 4-fluorocinnamic analog, which exhibits a nanomolar activity (IC50 2,1 nM) toward melanoma cells. This compound is over 2250 times more active than commercial antitumor agent doxorubicin (DOX). SAR analysis has revealed a correlation between the structure and the biological activity of the compounds. Using the molecular docking the relationship of the styryl lactone and the target protein important for prostate cancer was examined. The compounds with high inhibitory activity against prostate cancer cells have a high docking score and are capable to form a coordinative-covalent bond with a Fe2+ ion present in the active centre of the enzyme. 3DQSAR analysis, which was performed by methods of comparative CoMFA and CoMSIA fields, has formed a good predictive model between chemical structure and biological activity of the styryl lactone.</p>