Browsing by Subject "PHARMACOKINETICS"

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  • Hirschfield, Gideon M.; Beuers, Ulrich; Kupcinskas, Limas; Ott, Peter; Bergquist, Annika; Färkkilä, Martti; Manns, Michael P.; Pares, Albert; Spengler, Ulrich; Stiess, Michael; Greinwald, Roland; Prols, Markus; Wendum, Dominique; Drebber, Uta; Poupon, Raoul (2021)
    Background & Aims: In patients with primary biliary cholangitis (PBC), the efficacy of budesonide, a synthetic corticosteroid displaying high first-pass metabolism, is unresolved. In a placebo-controlled, double-blind trial, we evaluated the added-value of budesonide in those with PBC and ongoing risk of progressive disease despite ursodeoxycholic acid (UDCA) treatment. Methods: We evaluated 62 patients with PBC who had histologically confirmed hepatic inflammatory activity, according to the Ishak score, and an alkaline phosphatase (ALP) >1.5x upper limit of normal (ULN), after at least 6 months of UDCA therapy. Participants were randomly assigned 2:1 to receive budesonide (9 mg/day) or placebo once daily, for 36 months, with UDCA treatment (12-16 mg/kg body weight/day) maintained. Primary efficacy was defined as improvement of liver histology with respect to inflammation and no progression of fibrosis. Secondary outcomes included changes in biochemical markers of liver injury. Results: Recruitment challenges resulted in a study that was underpowered for the primary efficacy analysis. Comparing patients with paired biopsies only (n = 43), the primary histologic endpoint was not met (p>0.05). The proportion of patients with ALP = 15% decrease in ALP and normal bilirubin was higher in the budesonide group than in the placebo group at 12, 24, and 36 months (p Conclusion: Budesonide add-on therapy was not associated with improved liver histology in patients with PBC and insufficient response to UDCA; however, improvements in biochemical markers of disease activity were demonstrated in secondary analyses. Lay summary: Around one-third of patients with primary biliary cholangitis (PBC) needs additional medical therapy alongside ursodeoxycholic acid (UDCA) treatment. In this clinical trial, the addition of the corticosteroid budesonide did not improve liver histology; there were however relevant improvements in liver blood tests. (C) 2020 European Association for the Study of the Liver. Published by Elsevier B.V.
  • Tammela, Teuvo L.; Häggman, Michael; Ladjevardi, Sam; Taari, Kimmo; Isotalo, Taina; Lennernäs, Hans; Weis, Jan; von Below, Catrin; Wassberg, Cecilia; Lennernäs, Bo; Tolf, Anna; Axén, Niklas; Gölander, Carl-Gustaf; Ahlström, Håkan (2017)
    Purpose: We investigated the tolerability, safety and antitumor effects of a novel intraprostatic depot formulation of antiandrogen 2-hydroxyflutamide (in Nano-Zolid (R)) in men with localized prostate cancer. Materials and Methods: Two clinical trials, LPC-002 and LPC-003, were performed in a total of 47 men. The formulation was injected transrectally into the prostate under ultrasound guidance. In LPC-002 the effects on prostate specific antigen and prostate volume were measured for 6 months in 24 patients. In LPC-003 antitumor effects were evaluated by histopathology and magnetic resonance imaging including spectroscopy during 6 or 8 weeks in 23 patients. In each study testosterone and 2-hydroxyflutamide in plasma were measured as well as quality of life parameters. Results: In LPC-002 (mean dose 690 mg) a reduction was observed in prostate specific antigen and prostate volume. Average nadir prostate specific antigen and prostate volume were 24.9% and 14.0% below baseline, respectively. When increasing the dose in LPC-003 to 920 and 1,740 mg, average prostate specific antigen decreased 16% and 23% after 6 and 8 weeks, respectively. Magnetic resonance imaging and magnetic resonance spectroscopy showed morphological changes and a global reduction in metabolite concentrations following treatment, indicating an antitumor response. Injections did not result in hormone related side effects. Three serious adverse events were reported and all resolved with oral antibiotic treatment. Conclusions: Intraprostatic injections of 2-hydroxyflutamide depot formulations showed antitumor effects, and proved to be safe and tolerable. However, for better anticancer effects higher doses and better dose distribution are suggested.
  • Cajanus, Kristiina; Neuvonen, Mikko; Koskela, Outi; Kaunisto, Mari A.; Neuvonen, Pertti J.; Niemi, Mikko; Kalso, Eija (2018)
    We investigated factors affecting analgesic oxycodone concentrations after breast cancer surgery in 1,000 women. Preoperatively, we studied heat and cold pain sensitivities and anxiety scores. Postoperatively, rest and motion pain intensities were measured and intravenous oxycodone was administered until satisfactory analgesia. At this point, the mean oxycodone concentration (variation coefficient) was 33.3 ng/mL (66%) and it was 21.7 ng/mL (69%) when the patient requested oxycodone again. At both time points, the concentrations varied >100-fold between individuals. The analgesic oxycodone concentration was increased by 21.3% per motion pain intensity score on a 0-10 scale and by 22.3% if axillary clearance was performed instead of sentinel node biopsy (P <0.001). Forty-seven women who were older and less anxious than others (P <0.01) required no oxycodone. Anxiety, age, chronic pain, or preoperative pain sensitivity were not independently associated with the analgesic oxycodone concentration. CYP2D6 and CYP3A genotypes did not affect analgesic concentration or duration of analgesia.
  • Kolehmainen, Sara; Ylisaukko-Oja, Tero; Jokelainen, Jari; Koivusalo, Mirkka; Jokiranta, T. Sakari; Sipponen, Taina (2021)
    Objectives We set out to determine the reasons for serum vedolizumab (VDZ) trough concentration (TC) measurements in inflammatory bowel disease (IBD) patients and to evaluate treatment modifications after therapeutic drug measurement (TDM). We also evaluated the effect of increased dosing on patients' response to VDZ therapy. Methods We performed a retrospective cohort study of IBD patients who received VDZ therapy at Helsinki University Hospital and whose VDZ levels were measured between June 2014 and December 2018. Results Altogether, 90 patients (32 Crohn's disease and 58 ulcerative colitis) and 141 VDZ TC measurements were included. 24.1% of measurements took place during induction and 75.9% during the maintenance phase. During induction, 64.7% reached the target TC >20 mu g/ml. During maintenance therapy, 82.2% of VDZ TCs were within or exceeded the suggested target range of 5-15 mu g/ml. Reasons for TDM were: secondary nonresponse (44.0%), assessment of adequate VDZ TC (25.5%), primary nonresponse (12.8%), adverse events (6.4%), and other (11.3%). No treatment changes occurred after 60.3% of VDZ measurements. Increased dose frequency was used after 25.5% of VDZ measurements and 33.3% of these patients experienced improvement. Altogether, 31 (34.4%) patients discontinued the therapy due to inadequate treatment response. No anti-vedolizumab antibodies were detected. Conclusions During the maintenance of VDZ therapy, the majority of VDZ TCs were within the suggested range. Measurement of VDZ TC did not lead to any treatment changes in two-thirds of patients. Dose optimization occurred in a quarter of patients and a third of them benefited from it.
  • Itkonen, Matti K.; Tornio, Aleksi; Neuvonen, Mikko; Neuvonen, Pertti J.; Niemi, Mikko; Backman, Janne T. (2019)
    A recent in vitro study suggested that CYP2C8 is essential in the metabolism of desloratadine, an H1 receptor antagonist. If the proposed biotransformation mechanism takes place in vivo in humans, desloratadine could serve as a selective CYP2C8 probe substrate in drug-drug interaction studies. Glucuronide metabo-lites of clopidogrel and gemfibrozil act as time-dependent inhibitors of CYP2C8, but they have not been compared clinically. We conducted a randomized crossover study in 11 healthy subjects to characterize the involvement of CYP2C8 in desloratadine metabolism and to compare the CYP2C8 inhibitory strength of clopidogrel (300 and 75 mg on two following days) with that of gemfibrozil (600 mg BID for 5 days). Compared with placebo (control), clopidogrel increased the area under the plasma concentration-time curve (AUC(0-infinity)) and peak plasma concentration (C-max) of desloratadine to 280% (P = 3 x 10(-7)) and 165% (P = 0.0006), respectively. The corresponding increases by gemfibrozil were to 462% (P = 4 x 10(-7)) and 174% (P = 0.0006). Compared with placebo, clopidogrel and gemfibrozil decreased 3-hydroxyloratadine AUC(0-71h) to 52% (P = 5 x 10(-5)) and 6%(P = 2 X 10(-8)), respectively. Moreover, the 3-hydroxydesloratadine: desloratadine AUC(0-71h) ratios were 21% (P = 7 x 10(-10)) and 1.7% (P = 8 x 10(-11)) of control during the clopidogrel and gemfibrozil phases. Our results confirm that CYP2C8 plays a critical role in the formation of 3-hydroxydesloratadine in humans, making desloratadine a potential CYP2C8 probe substrate. Furthermore, the findings corroborate the previous estimates that clinically relevant doses of clopidogrel cause strong CYP2C8 inhibition, whereas those of gemfibrozil almost completely inactivate the enzyme in humans.
  • Itkonen, Matti K.; Tornio, Aleksi; Filppula, Anne M.; Neuvonen, Mikko; Neuvonen, Pertti J.; Niemi, Mikko; Backman, Janne T. (2018)
    The oxidation of montelukast is mainly mediated by cytochrome P450 (CYP) 2C8, but other mechanisms may contribute to its disposition. In healthy volunteers, we investigated the effects of two widely used P2Y(12) inhibitors on montelukast pharmacokinetics. Clopidogrel (300mg on day 1 and 75mg on day 2) increased the area under the plasma concentration-time curve (AUC) of montelukast 2.0-fold (90% confidence interval (CI) 1.72-2.28, P <0.001) and decreased the M6:montelukast AUC(0-7h) ratio to 45% of control (90% CI 40-50%, P <0.001). Prasugrel (60mg on day 1 and 10mg on day 2) had no clinically meaningful effect on montelukast pharmacokinetics. Our results imply that clopidogrel is at least a moderate inhibitor of CYP2C8, but prasugrel is not a clinically relevant CYP2C8 inhibitor. The different interaction potentials of clopidogrel and prasugrel are important to consider when antiplatelet therapy is planned for patients at risk for polypharmacy with CYP2C8 substrates.
  • Itkonen, Matti K.; Tornio, Aleksi; Lapatto-Reiniluoto, Outi; Neuvonen, Mikko; Neuvonen, Pertti J.; Niemi, Mikko; Backman, Janne T. (2019)
    Dasabuvir is mainly metabolized by cytochrome P450 (CYP) 2C8 and is predominantly used in a regimen containing ritonavir. Ritonavir and clopidogrel are inhibitors of CYP3A4 and CYP2C8, respectively. In a randomized, crossover study in 12 healthy subjects, we examined the impact of clinical doses of ritonavir (for 5 days), clopidogrel (for 3 days), and their combination on dasabuvir pharmacokinetics, and the effect of ritonavir on clopidogrel. Clopidogrel, but not ritonavir, increased the geometric mean AUC(0-infinity) of dasabuvir 4.7-fold; range 2.0-10.1-fold (P = 8 center dot 10(-7)), compared with placebo. Clopidogrel and ritonavir combination increased dasabuvir AUC(0-infinity) 3.9-fold; range 2.1-7.9-fold (P = 2 center dot 10(-6)), compared with ritonavir alone. Ritonavir decreased the AUC(0-4h) of clopidogrel active metabolite by 51% (P = 0.0001), and average platelet inhibition from 51% without ritonavir to 31% with ritonavir (P = 0.0007). In conclusion, clopidogrel markedly elevates dasabuvir concentrations, and patients receiving ritonavir are at risk for diminished clopidogrel response.
  • Salminen, Jarno; van Gils, Mark; Paloheimo, Markku; Yli-Hankala, Arvi (2016)
    Neuromuscular blockade is usually monitored using train-of-four (TOF) stimulation pattern. A TOF ratio of higher than 90 % is recommended to reduce the risk of adverse effects after anaesthesia. TOF ratio 90 % is used in clinical practice with all different neuromuscular monitors. Kinemyography (KMG) is one commercialized method to obtain numerical TOF values. We compared the KMG data obtained with Datex M-NMT MechanoSensor (TM) module, to the EMG data collected with Datex ElectroSensor (TM), during clinical anaesthesia. Ipsilateral comparisons of the sensors were performed in 20 female patients during clinical procedures in propofol-remifentanil anaesthesia. After initial bolus dose of rocuronium (0.6 mg/kg), the spontaneous recovery of TOF ratio and T1 % were monitored. KMG gave higher TOF values than EMG. The difference was significant at KMG TOF values of 40 % or higher. After anaesthetic induction, but before administration of rocuronium, both TOF sensor values drifted from the TOF value of 1.0, showing either significant spontaneous fade (T1 > T4) or tendency of reverse fade (T1 <T4). KMG overestimates the recovery from neuromuscular blockade when compared with EMG. KMG and EMG cannot be used interchangeably, and TOF ratio 90 % cannot be considered as adequate level of recovery with all monitoring devices.
  • Honkavaara, Juhana M.; Raekallio, Marja R.; Syrja, Pernilla M.; Pypendop, Bruno H.; Knych, Heather K.; Kallio-Kujala, Ira J.; Vainio, Outi M. (2020)
    Objective To quantify the peripheral selectivity of vatinoxan (L-659,066, MK-467) in dogs by comparing the concentrations of vatinoxan, dexmedetomidine and levo-medetomidine in plasma and central nervous system (CNS) tissue after intravenous (IV) coadministration of vatinoxan and medetomidine. Study design Experimental, observational study. Animals A group of six healthy, purpose-bred Beagle dogs (four females and two males) aged 6.5 +/- 0.1 years (mean +/- standard deviation). Methods All dogs were administered a combination of medetomidine (40 mu g kg(-1)) and vatinoxan (800 mu g kg(-1)) as IV bolus. After 20 minutes, the dogs were euthanized with an IV overdose of pentobarbital (140 mg kg(-1)) and both venous plasma and CNS tissues (brain, cervical and lumbar spinal cord) were harvested. Concentrations of dexmedetomidine, levomedetomidine and vatinoxan in all samples were quantified by liquid chromatography-tandem mass spectrometry and data were analyzed with nonparametric tests with post hoc corrections where appropriate. Results All dogs became deeply sedated after the treatment. The CNS-to-plasma ratio of vatinoxan concentration was approximately 1:50, whereas the concentrations of dexmedetomidine and levomedetomidine in the CNS were three- to seven-fold of those in plasma. Conclusions and clinical relevance With the doses studied, these results confirm the peripheral selectivity of vatinoxan in dogs, when coadministered IV with medetomidine. Thus, it is likely that vatinoxan preferentially antagonizes alpha(2)-adrenoceptors outside the CNS.
  • Kasparyan, Gari; Poojari, Chetan; Rog, Tomasz; Hub, Jochen S. (2020)
    Itraconazole is a triazole drug widely used in the treatment of fungal infections, and it is in clinical trials for treatment of several cancers. However, the drug suffers from poor solubility, while experiments have shown that itraconazole delivery in liposome nanocarriers improves both circulation half-life and tissue distribution. The drug release mechanism from the nanocarrier is still unknown, and it depends on several factors including membrane stability against defect formation. In this work, we used molecular dynamics simulations and potential of mean force (PMF) calculations to quantify the influence of itraconazole on pore formation over lipid membranes, and we compared the effect by itraconazole with a pore-stabilizing effect by the organic solvent dimethyl sulfoxide (DMSO). According to the PMFs, both itraconazole and DMSO greatly reduce the free energy of pore formation, by up to similar to 20 kJ mol(-1). However, whereas large concentrations of itraconazole of 8 mol % (relative to lipid) were required, only small concentrations of a few mole % DMSO (relative to water) were sufficient to stabilize pores. In addition, itraconazole and DMSO facilitate pore formation by different mechanisms. Whereas itraconazole predominantly aids the formation of a partial defect with a locally thinned membrane, DMSO mainly stabilizes a transmembrane water needle by shielding it from the hydrophobic core. Notably, the two distinct mechanisms act cooperatively upon adding both itraconazole and DMSO to the membrane, as revealed by an additional reduction of the pore free energy. Overall, our simulations reveal molecular mechanisms and free energies of membrane pore formation by small molecules. We suggest that the stabilization of a locally thinned membrane as well as the shielding of a transmembrane water needle from the hydrophobic membrane core may be a general mechanism by which amphiphilic molecules facilitate pore formation over lipid membranes at sufficient concentrations.
  • Hälli, Outi; Haimi, Minna; Laurila, Tapio; Oliviero, Claudio; Viitasaari, Elina Anna Maria; Orro, Toomas; Peltoniemi, Olli Aarno Tapio; Scheinin, Mika; Siren, Saija; Valros, Anna Elisabet; Heinonen, Mari Leena (2018)
    Background: Infection with respiratory pathogens can influence production as well as animal welfare. There is an economical and ethical need to treat pigs that suffer from respiratory diseases. Our aim was the evaluation of the possible effects of oral NSAID medication given in feed in acute outbreaks of respiratory disease in finishing pigs. The short-and long-term impact of NSAID dosing on clinical signs, daily weight gain, blood parameters and behaviour of growing pigs in herds with acute respiratory infections were evaluated. Four finishing pig farms suffering from acute outbreaks of respiratory disease were visited thrice after outbreak onset (DAY 0, DAY 3 and DAY 30). Pigs with the most severe clinical signs (N = 160) were selected as representative pigs for the herd condition. These pigs were blood sampled, weighed, evaluated clinically and their behaviour was observed. After the first visit, half of the pens (five pigs per pen in four pens totalling 20 representative pigs per herd, altogether 80 pigs in four herds) were treated with oral ketoprofen (target dose 3 mg/kg) mixed in feed for three days and the other half (80 pigs) with a placebo. In three of the herds, some pigs were treated also with antimicrobials, and in one herd the only pharmaceutical treatment was ketoprofen or placebo. Results: Compared to the placebo treatment, dosing of ketoprofen reduced sickness behaviour and lowered the rectal temperature of the pigs. Clinical signs, feed intake or blood parameters were not different between the treatment groups. Ketoprofen treatment was associated with somewhat reduced weight gain over the 30-day follow-up period. Concentration analysis of the S-and R-enantiomers of ketoprofen in serum samples collected on DAY 3 indicated successful oral drug administration. Conclusions: Ketoprofen mainly influenced the behaviour of the pigs, while it had no effect on recovery from respiratory clinical signs. However, the medication may have been started after the most severe clinical phase of the respiratory disease was over, and this delay might complicate the evaluation of treatment effects. Possible negative impact of ketoprofen on production parameters requires further evaluation.
  • Kallio-Kujala, I. J.; Bennett, R. C.; Raekallio, M. R.; Yatkin, E.; Meierjohann, A.; Savontaus, E.; Scheinin, M.; Spillmann, T.; Vainio, O. M. (2018)
    The commonly used sedative alpha(2)-adrenoceptor agonist dexmedetomidine has adverse cardiovascular effects in dogs that can be prevented by concomitant administration of the peripherally acting alpha(2)-adrenoceptor antagonist MK-467. An ancillary effect of dexmedetomidine is to decrease insulin release from the pancreas, whereas MK-467 stimulates insulin release. This study assessed the effects of co-administered dexmedetomidine and MK-467 in a canine glibenclamide-induced hypoglycaemia model. In a randomised, cross-over experiment, eight beagle dogs received five intravenous treatments, comprising two administrations of saline, with dexmedetomidine or dexmedetomidine and MK-467, and three administrations of glibenclamide, with saline, dexmedetomidine or dexmedetomidine and MK-467. Plasma concentrations of glucose, lactate, insulin, glucagon and the test drugs were monitored. Administration of glibenclamide significantly increased insulin secretion and decreased blood glucose concentrations. Dexmedetomidine counteracted glibenclamide-evoked hypoglycaemia. This was opposed by the alpha(2)-adrenoceptor antagonist MK-467, but the glibenclamide-evoked hypoglycaemia was not potentiated by co-administration of dexmedetomidine and MK-467. None of the dogs developed uncontrolled hypoglycaemia. Thus, the combination of dexmedetomidine and MK-467 appeared to be safe in this canine hypoglycaemia model. Nevertheless, when MK-467 is used to alleviate the undesired cardiovascular effects of alpha(2)-adrenoceptor agonists in dogs, it should be used with caution in animals at risk for hypoglycaemia because of its insulin-releasing and hypoglycaemic effects. (C) 2018 The Author(s). Published by Elsevier Ltd.
  • Alanne, Leena; Bhide, Amarnath; Hoffren, Jonna; Lantto, Juulia; Huhta, Heikki; Kokki, Merja; Haapsamo, Mervi; Acharya, Ganesh; Räsänen, Juha (2020)
    Introduction We hypothesized that nifedipine and sildenafil would have no detrimental effects on placental hemodynamics and gas exchange under fetal hypoxemia. Methods In 33 chronically instrumented fetal sheep, placental volume blood flow (QPlac) and umbilical artery (UA) vascular impedance were measured by Doppler ultrasonography. Fetal carotid artery blood pressure and blood gas values were monitored. After baseline data collection, maternal and fetal hypoxemia were induced. Following hypoxemia phase data collection, 12 fetuses received sildenafil and 9 fetuses nifedipine infusion, and 12 fetuses served as controls receiving saline infusion. Data were collected 30 and 120 min after infusion was started. Then maternal oxygenation was normalized and normoxemia phase data were collected, while infusion was continued. Results Hypoxemia significantly decreased fetal pO2 and blood pressure. In the sildenafil group at 30- and 120-min hypoxemia + infusion phases, fetal blood pressure and QPlac were significantly lower and pCO2 higher than at baseline without returning to baseline level at normoxemia + infusion phase. In hypoxemia, nifedipine did not affect fetal blood pressure or placental hemodynamics. Both in the sildenafil and nifedipine groups, fetal pO2 remained significantly lower at normoxemia + infusion phase than in the control group. Umbilical artery vascular impedance did not change during the experiment. Discussion In fetal hypoxemia, sildenafil had detrimental effects on placental hemodynamics that disturbed placental gas exchange. Nifedipine did not alter placental hemodynamics in hypoxemia but disturbed placental gas exchange upon returning to normoxemia. Umbilical artery vascular impedance did not reflect alterations in placental hemodynamics.
  • Tapio, H.; Raekallio, M. R.; Mykkänen, A.; Männikkö, S.; Scheinin, M.; Bennett, R. C.; Vainio, O. (2019)
    Background Medetomidine suppresses cardiovascular function and reduces gastrointestinal motility in horses mainly through peripheral alpha(2)-adrenoceptors. Vatinoxan, a peripheral alpha(2)-antagonist, has been shown experimentally to alleviate the adverse effects of some alpha(2)-agonists in horses. However, vatinoxan has not been investigated during constant-rate infusion (CRI) of medetomidine in standing horses. Objectives To evaluate effects of vatinoxan on cardiovascular function, gastrointestinal motility and on sedation level during CRI of medetomidine. Study design Experimental, randomised, blinded, cross-over study. Methods Six healthy horses were given medetomidine hydrochloride, 7 mu g/kg i.v., without (MED) and with (MED+V) vatinoxan hydrochloride, 140 mu g/kg i.v., followed by CRI of medetomidine at 3.5 mu g/kg/h for 60 min. Cardiorespiratory variables were recorded and borborygmi and sedation levels were scored for 120 min. Plasma drug concentrations were measured. The data were analysed using repeated measures ANCOVA and paired t-tests as appropriate. Results Initially heart rate (HR) was significantly lower and mean arterial blood pressure (MAP) significantly higher with MED compared with MED+V. For example at 10 min HR (mean +/- s.d.) was 26 +/- 2 and 31 +/- 5 beats/minute (P = 0.04) and MAP 129 +/- 15 and 103 +/- 13 mmHg (P
  • Pitkänen, Hanna; Jouppila, Annukka; Lemponen, Marja; Ilmakunnas, Minna; Ahonen, Jouni; Lassila, Riitta (2017)
    Introduction: Factor XIII (FXIII) cross-links fibrin, completing blood coagulation. Congenital FXIII deficiency is managed with plasma-derived FXIII (pdFXIII) or recombinant FXIII (rFXIII) concentrates. Aim: As the mechanisms protecting patients with low FXIII levels ( Methods: Patients received initially rFXIII (35 IU/kg, A-subunit) following with pdFXIII at 1250 IU or 2500 IU (1230 IU/kg) monthly. TG (CAT), thromboelastometry (ROTEM), prothrombin fragments F1 + 2, fibrinogen and FXIII activity (FXIII:C) were measured at baseline and one-hour recovery. Results: FXIII was at the target level of 20 +/- 6 IU/dL at the 4-week trough. rFXIII corrected FXIII to 98 +/- 15 and high-dose pdFXIII to a level of 90 +/- 6, whereas low-dose/half dose pdFXIII reached 45 +/- 4 IU/dL. Although fibrinogen (Clauss Method) was normal, coagulation in FIBTEM was impaired, which FXIII administration tended to correct. CAT implied 1.6- to 1.9-fold enhanced TG, which FXIII administration normalized. Inhibition of fibrin polymerization by Gly-Pro-Arg-Pro peptide mimicked FXIII deficiency in CAT by enhancing TG both in control and FXIII recovery plasma. Antithrombin, alpha 2-macroblobulin-thrombin complex and prothrombin were normal, whereas F1 + 2 were elevated compatible with in vivo TG. Discussion: FXIII deficiency impairs fibrinogen function and fibrin formation simultaneously enhancing TG on the poorly polymerizing fibrin strands, when fibrin's antithrombin I -like function is absent. Our study suggests an inverse link between low FXIII levels and enhanced TG modifying structure-function relationship of fibrin to support hemostasis. (C) 2016 Elsevier Ltd. All rights reserved.
  • Fihlman, Mari; Karru, E.; Varpe, P.; Huhtinen, H.; Hagelberg, N.; Saari, T.; Olkkola, K. T. (2020)
    Since patients often experience pain and unpleasantness during a colonoscopy, the present study aimed to evaluate the efficacy and safety of sublingually administered fentanyl tablets for pain treatment. Furthermore, since the use of intravenous drugs significantly increases colonoscopy costs, sublingual tablets could be a cost-effective alternative to intravenous sedation. We conducted a prospective placebo-controlled randomized study of 158 patients to evaluate the analgesic effect of a 100 mu g dose of sublingual fentanyl administered before a colonoscopy. Pain, sedation, nausea, and satisfaction were assessed during the colonoscopy by the patients as well as the endoscopists and nurses. Respiratory rate and peripheral arteriolar oxygen saturation were monitored throughout the procedure. There were no differences between the fentanyl and placebo groups in any of the measured variables. The median pain intensity values, as measured using a numerical rating scale, were 4.5 in the fentanyl group and 5 in the placebo group. The sedation and oxygen saturation levels and the respiratory rate did not differ between the groups. The majority of the colonoscopies were completed.Our results indicate that a 100 mu g dose of sublingual fentanyl is not beneficial compared to the placebo in the treatment of procedural pain during a colonoscopy.
  • Lehtisalo, Minna; Keskitalo, Jenni E.; Tornio, Aleksi; Lapatto-Reiniluoto, Outi; Deng, Feng; Jaatinen, Taina; Viinamäki, Jenni; Neuvonen, Mikko; Backman, Janne T.; Niemi, Mikko (2020)
    Xanthine oxidase inhibitors febuxostat and allopurinol are commonly used in the treatment of gout. Febuxostat inhibits the breast cancer resistance protein (BCRP) in vitro. Rosuvastatin is a BCRP substrate and genetic variability in BCRP markedly affects rosuvastatin pharmacokinetics. In this study, we investigated possible effects of febuxostat and allopurinol on rosuvastatin pharmacokinetics. In a randomized crossover study with 3 phases, 10 healthy volunteers ingested once daily placebo for 7 days, 300 mg allopurinol for 7 days, or placebo for 3 days, followed by 120 mg febuxostat for 4 days, and a single 10 mg dose of rosuvastatin on day 6. Febuxostat increased the peak plasma concentration and area under the plasma concentration-time curve of rosuvastatin 2.1-fold (90% confidence interval 1.8-2.6; P = 5 x 10(-5)) and 1.9-fold (1.5-2.5; P = 0.001), but had no effect on rosuvastatin half-life or renal clearance. Allopurinol, on the other hand, did not affect rosuvastatin pharmacokinetics. In vitro, febuxostat inhibited the ATP-dependent uptake of rosuvastatin into BCRP-overexpressing membrane vesicles with a half-maximal inhibitory concentration of 0.35 mu M, whereas allopurinol showed no inhibition with concentrations up to 200 mu M. Taken together, the results suggest that febuxostat increases rosuvastatin exposure by inhibiting its BCRP-mediated efflux in the small intestine. Febuxostat may, therefore, serve as a useful index inhibitor of BCRP in drug-drug interaction studies in humans. Moreover, concomitant use of febuxostat may increase the exposure to BCRP substrate drugs and, thus, the risk of dose-dependent adverse effects.
  • Ahlström, Sirkku; Bergman, Paula; Jokela, Ritva; Ottensmann, Linda; Ahola-Olli, Ari; Pirinen, Matti; Olkkola, Klaus T.; Kaunisto, Mari A.; Kalso, Eija (2021)
    Background: Rocuronium, a common neuromuscular blocking agent, is mainly excreted unchanged in urine (10-25%) and bile ( 70%). Age, sex, liver blood flow, smoking, medical conditions, and ethnic background can affect its pharmacological actions. However, reasons for the wide variation in rocuronium requirements are mostly unknown. We hypothesised that pharmacogenetic factors might explain part of the variation. Methods: One thousand women undergoing surgery for breast cancer were studied. Anaesthesia was maintained with propofol (50-100 mg kg(-1) min(-1)) and remifentanil (0.05-0.25 mg kg(-1) min(-1)). Neuromuscular block was maintained with rocuronium to keep the train-of-four ratio at 0-10%. DNA was extracted from peripheral blood and genotyped with a next-generation genotyping array. The genome-wide association study (GWAS) was conducted using an additive linear regression model with PLINK software. The FINEMAP tool and data from the Genotype-Tissue Expression project v8 were utilised to study the locus further. Results: The final patient population comprised 918 individuals. Of the clinical variables tested, age, BMI, ASA physical status, and total dose of propofol correlated significantly (all P Conclusions: Genetic variation in the gene SLCO1A2, encoding OATP1A2, an uptake transporter, accounted for 4% of the variability in rocuronium consumption. The underlying mechanism remains unknown.
  • Karhu, S. Tuuli; Kinnunen, Sini M.; Tölli, Marja; Välimäki, Mika J.; Szabo, Zoltan; Talman, Virpi; Ruskoaho, Heikki (2020)
    Doxorubicin is a widely used anticancer drug that causes dose-related cardiotoxicity. The exact mechanisms of doxorubicin toxicity are still unclear, partly because most in vitro studies have evaluated the effects of short-term high-dose doxorubicin treatments. Here, we developed an in vitro model of long-term low-dose administration of doxorubicin utilizing human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). Moreover, given that current strategies for prevention and management of doxorubicin-induced cardiotoxicity fail to prevent cancer patients developing heart failure, we also investigated whether the GATA4-targeted compound 3i-1000 has cardioprotective potential against doxorubicin toxicity both in vitro and in vivo. The final doxorubicin concentration used in the chronic toxicity model in vitro was chosen based on cell viability data evaluation. Exposure to doxorubicin at the concentrations of 1-3 mu M markedly reduced (60%) hiPSC-CM viability already within 48 h, while a 14-day treatment with 100 nM doxorubicin concentration induced only a modest 26% reduction in hiPCS-CM viability. Doxorubicin treatment also decreased DNA content in hiPSC-CMs. Interestingly, the compound 3i-1000 attenuated doxorubicin-induced increase in pro-B-type natriuretic peptide (proBNP) expression and caspase-3/7 activation in hiPSC-CMs. Moreover, treatment with 3i-1000 for 2 weeks (30 mg/kg/day, i.p.) inhibited doxorubicin cardiotoxicity by restoring left ventricular ejection fraction and fractional shortening in chronic in vivo rat model. In conclusion, the results demonstrate that long-term exposure of hiPSC-CMs can be utilized as an in vitro model of delayed doxorubicin-induced toxicity and provide in vitro and in vivo evidence that targeting GATA4 may be an effective strategy to counteract doxorubicin-induced cardiotoxicity.
  • Palada, Vinko; Kaunisto, Mari A.; Kalso, Eija (2018)
    Purpose of reviewThe review describes recent advances in genetics and genomics of postoperative pain, the association between genetic variants and the efficacy of analgesics, and the role of pharmacogenomics in the selection of appropriate analgesic treatments for postoperative pain.Recent findingsRecent genetic studies have reported associations of genetic variants in catechol-O-methyltransferase (COMT), brain-derived neurotrophic factor (BDNF), voltage-gated channel alpha subunit 11 (SCN11A) and -opioid receptor (OPRM1) genes with postoperative pain. The recent pharmacogenetics studies revealed an association of the organic cation transporter 1 (OCT1) and ATP-binding cassette C3 (ABCC3) polymorphisms with morphine-related adverse effects, an effect of polymorphisms in cytochrome P450 gene CYP2D6 on the analgesic efficacy of tramadol and no effect of CYP2C8 and CYP2C9 variants on efficacy of piroxicam.SummaryGenetic variants associate with inter-individual variability in drug responses and they can affect pain sensitivity and intensity of postoperative pain. Despite the recent progress in genetics and genomics of postoperative pain, it is still not possible to precisely predict the patients who are genetically predisposed to have severe postoperative pain or who develop chronic postoperative pain.