BACKGROUND: Alcohol dependence and associated cognitive impairments apparently result from neuroadaptations to chronic alcohol consumption involving changes in expression of multiple genes. Here we investigated whether transcription factors of Nuclear Factor-kappaB (NF-kappaB) family, controlling neuronal plasticity and neurodegeneration, are involved in these adaptations in human chronic alcoholics. METHODS AND FINDINGS: Analysis of DNA-binding of NF-kappaB (p65/p50 heterodimer) and the p50 homodimer as well as NF-kappaB proteins and mRNAs was performed in postmortem human brain samples from 15 chronic alcoholics and 15 control subjects. The prefrontal cortex involved in alcohol dependence and cognition was analyzed and the motor cortex was studied for comparison. The p50 homodimer was identified as dominant kappaB binding factor in analyzed tissues. NF-kappaB and p50 homodimer DNA-binding was downregulated, levels of p65 (RELA) mRNA were attenuated, and the stoichiometry of p65/p50 proteins and respective mRNAs was altered in the prefrontal cortex of alcoholics. Comparison of a number of p50 homodimer/NF-kappaB target DNA sites, kappaB elements in 479 genes, down- or upregulated in alcoholics demonstrated that genes with kappaB elements were generally upregulated in alcoholics. No significant differences between alcoholics and controls were observed in the motor cortex. CONCLUSIONS: We suggest that cycles of alcohol intoxication/withdrawal, which may initially activate NF-kappaB, when repeated over years downregulate RELA expression and NF-kappaB and p50 homodimer DNA-binding. Downregulation of the dominant p50 homodimer, a potent inhibitor of gene transcription apparently resulted in derepression of kappaB regulated genes. Alterations in expression of p50 homodimer/NF-kappaB regulated genes may contribute to neuroplastic adaptation underlying alcoholism.

To reach the bloodstream, an orally administered drug must be absorbed through the small intestine and avoid extensive clearance in the liver. Estimating these parameters in vitro is therefore important in drug discovery and development. This can be achieved with cellular models that simulate human organ function, such as Caco-2 cells and primary hepatocytes. No model fits every scenario, however, and this thesis aimed at using proteomic and functional analysis to better understand and increase the applicability of in vitro models based on Caco-2 cells and human hepatocytes.

First, the proteome of filter-grown Caco-2 cells was analyzed. This included near-complete coverage of enterocyte-related proteins, and over 300 ADME proteins. Further, by scaling uptake transport kinetics from Caco-2 cells to human jejunum, the importance of considering in vitro­-in vivo expression differences to correctly interpret in vitro transport studies was demonstrated.

Focus was then turned to hepatocytes, where proteomics was used as a basis for the successful development of an apoptosis inhibition protocol for restoration of attachment properties and functionality in suboptimal batches of cryopreserved human hepatocytes. As a spin-off project, image-based quantification of cell debris was developed into a novel apoptosis detection method.

Next, the in vivo heterogeneity of human hepatocytes was explored in an in vitro setting, where it was observed that human hepatocyte batches contain a wide range of cell sizes. By separating the cells into different size fractions, it was found that hepatocyte size corresponds to the microarchitectural zone of origin in the liver. Size separation can thus be used to study zonated liver functions in vitro.

Finally, the proteomes of the major types of non-parenchymal liver cells were analyzed, i.e. liver sinusoidal endothelial cells, Kupffer cells, and hepatic stellate cells. The different cell types all had distinctly different proteomes, and the expression of certain important ADME proteins indicated that non-parenchymal cells participate in drug disposition.

In conclusion, this thesis has improved the phenotypic understanding and extended the applicability of Caco-2 cells and primary human hepatocytes, two of the most important in vitro models for studies of small intestinal and hepatic drug disposition.

Apoptosis is a controlled form of cell death that can be induced by various diseases and exogenous toxicants. Common apoptosis detection methods rely on fluorescent markers, which necessitates the use of costly reagents and time-consuming labeling procedures. Label-free methods avoid these problems, but often require specialized instruments instead. Here, we utilize apoptotic cell disintegration to develop a novel label-free detection method based on the quantification of subcellular debris particles in bright-field microscopy images. Debris counts show strong correlations with fluorescence-based annexin V staining, and can be used to study concentration-dependent and temporal apoptosis activation. The method is rapid, low-cost, and easy to apply, as the only experimental step comprises bright-field imaging of culture media samples, followed by automated image processing. The late-stage nature of the debris measurement means that the method can complement other, established apoptosis assays, and its accessibility will allow a wider community of researchers to study apoptotic cell death.

Human hepatocytes show marked differences in cell size, gene expression, and function throughout the liver lobules, an arrangement termed liver zonation. However, it is not clear if these zonal size differences, and the associated phenotypic differences, are retained in isolated human hepatocytes, the “gold standard” for in vitro studies of human liver function. Here, we therefore explored size differences among isolated human hepatocytes and investigated whether separation by size can be used to study liver zonation in vitro. We used counterflow centrifugal elutriation to separate cells into different size fractions and analyzed them with label-free quantitative proteomics, which revealed an enrichment of 151 and 758 proteins (out of 5163) in small and large hepatocytes, respectively. Further analysis showed that protein abundances in different hepatocyte size fractions recapitulated the in vivo expression patterns of previously described zonal markers and biological processes. We also found that the expression of zone-specific cytochrome P450 enzymes correlated with their metabolic activity in the different fractions. In summary, our results show that differences in hepatocyte size matches zonal expression patterns, and that our size fractionation approach can be used to study zone-specific liver functions in vitro.

Background & Aims The human liver functions through a complex interplay between parenchymal and non-parenchymal cells. Mass spectrometry-based proteomic analysis of intact tissue has provided an in-depth view of the human liver proteome. However, the predominance of parenchymal cells (hepatocytes) means that the total tissue proteome mainly reflects hepatocyte expression. Here we therefore set out to analyse the proteomes of the major parenchymal and non-parenchymal cell types in the human liver.

Methods We applied quantitative label-free proteomic analysis on the major cell types of the human liver: hepatocytes, liver endothelial cells, Kupffer cells and hepatic stellate cells.

Results We identified 9791 proteins, revealing distinct protein expression profiles across cell types, whose in vivo relevance was shown by the presence of cell-type-specific proteins. Analysis of proteins related to the immune system indicated that mechanisms of immune-mediated liver injury include the involvement of several cell types. Furthermore, in-depth investigation of proteins related to the absorption, distribution, metabolism, excretion and toxicity (ADMET) of xenobiotics showed that ADMET-related tasks are not exclusively confined to hepatocytes, and that non-parenchymal cells may contribute to drug transport and metabolism.

Conclusions Overall, the data we provide constitute a unique resource for exploring the proteomes of the major types of human liver cells, which will facilitate an improved understanding of the human liver in health and disease.

Primary human hepatocytes are used in all facets of liver research, from in vitro studies of xenobiotic disposition and toxicity to the clinical management of liver failure. Unfortunately, cellular stress during isolation and cryopreservation causes a highly unpredictable loss of the ability to attach and form cell-matrix and cell-cell interactions. Reasoning that this problem could be mitigated at the post-thawing stage, we applied label-free quantitative global proteomics to analyze differences between attached and non-attached fractions of cryopreserved human hepatocyte batches. Hepatocytes that were unable to attach to a collagen matrix showed many signs of cellular stress, including a glycolytic phenotype and activation of the heat shock response, ultimately leading to apoptosis activation. Further analysis of the activated stress pathways revealed an increase in early apoptosis immediately post-thawing, which suggested the possibility of stress reversal. Therefore, we transiently treated the cells with compounds aimed at decreasing cellular stress via different mechanisms. Brief exposure to the pan-caspase apoptosis inhibitor Z-VAD-FMK restored attachment ability and promoted a differentiated morphology, as well as formation of 3D spheroids. Further, Z-VAD-FMK treatment restored metabolic and transport functions, with maintained sensitivity to hepatotoxic insults. Altogether, this study shows that differentiation and function of suboptimal human hepatocytes can be restored after cryopreservation, thus markedly increasing the availability of these precious cells.

Caco-2 cells are widely used in studies of intestinal cell physiology and drug transport. Here, the global proteome of filter-grown Caco-2 cells was quantified using the total protein approach and compared with the human colon and jejunum proteomes. In total, 8096 proteins were identified. In-depth analysis of proteins defining enterocyte differentiation—including brush-border hydrolases, integrins, and adherens and tight junctions—gave near-complete coverage of the expected proteins. Three hundred twenty-seven absorption, distribution, metabolism and excretion proteins were identified, including 112 solute carriers and 20 ATP-binding cassette transporters. OATP2B1 levels were 16-fold higher in Caco-2 cells than in jejunum. To investigate the impact of this difference on in vitro-in vivo extrapolations, we studied the uptake kinetics of the OATP2B1 substrate pitavastatin in Caco-2 monolayers, and found that the contribution of OATP2B1 was 60%-70% at clinically relevant intestinal concentrations. Pitavastatin kinetics was combined with transporter concentrations to model the contribution of active transport and membrane permeation in the jejunum. The lower OATP2B1 expression in jejunum led to a considerably lower transporter contribution (<5%), suggesting that transmembrane diffusion dominates pitavastatin absorption in vivo. In conclusion, we present the first in-depth quantification of the filter-grown Caco-2 proteome. We also demonstrate the crucial importance of considering transporter expression levels for correct interpretation of drug transport routes across the human intestine.

Background

ACD856 is a positive allosteric modulator of tropomyosin receptor kinase (Trk) receptors which has shown to have pro-cognitive and anti-depressant-like effects in various animal models. It is currently in clinical development for the treatment of Alzheimer’s disease and other disorders where cognition is impaired and is also considered for indications such as depression or other neuropsychiatric diseases. ACD856 has a novel mechanism of action modulating the activity of the Trk-receptors, resulting in increased stimulation of the neurotrophin signaling pathways. Previous studies applying single intravenous and oral doses of ACD856 indicate that ACD856 is safe and well-tolerated by healthy volunteer subjects, and that it has suitable safety and pharmacokinetic properties for further clinical development.

Objectives

To investigate the safety and tolerability of 7 days of treatment with multiple ascending oral doses of ACD856 in healthy subjects, and to characterize its pharmacokinetic (PK) properties. In addition, pharmacodynamic effects of ACD856 using quantitative electroencephalography (qEEG) as an indicator for central target engagement were assessed.

Design

This was a prospective, phase I, double-blind, parallel-group, placebo-controlled, randomized study of the safety, tolerability, PK and pharmacodynamics of multiple ascending oral doses of ACD856 in healthy subjects. ACD856 or placebo were administered in 3 ascending dose cohorts of 8 subjects. Within each cohort, subjects were randomized to receive either ACD856 (n=6) or placebo (n=2).

Setting

The study was conducted at a First-in-Human unit in Sweden.

Participants

Twenty-four healthy male and female subjects.

Intervention

The study medication was administered as an oral solution, with ACD856 or the same contents without the active ingredient (placebo). The dose levels ranged from 10 mg to 90 mg. ACD856 was administered once daily for 7 days, targeting steady state.

Measurements

Safety and tolerability assessments included adverse events, laboratory, vital signs, 12-lead electrocardiogram (ECG), physical examination, assessment of stool frequency and questionnaires to assess symptoms of anxiety, depression, as well as suicidal ideation and behavior. In addition, cardiodynamic ECGs were extracted to evaluate cardiac safety. PK parameters were calculated based on measured concentrations of ACD856 in plasma, urine, and cerebrospinal fluid (CSF) samples. Metabolite profiling, characterization and analysis was performed based on and urine samples. qEEG was recorded for patients in the two highest dose cohorts (30 and 90 mg/day) as a pharmacodynamic assessment to explore central target engagement.

Results

Treatment with ACD856 was well tolerated with no serious adverse events. No treatment emergent or dose related trends were observed for any of the safety assessments. ACD856 was rapidly absorbed and reached maximum plasma exposure at 30 to 45 minutes after administration. Steady state was reached before Day 6, with an elimination half-life at steady state of approximately 20 hours. At steady state, ACD856 exhibited accumulation ratios for Cmax and AUC of approximately 1.6 and 1.9 respectively. The exposure, Cmax and AUC0-24, increased proportionally with the dose. There was no unchanged ACD856 detected in urine. The metabolic pattern in urine and plasma was similar, and in alignment with the metabolites observed in preclinical toxicology studies. The level of ACD856 measured in CSF at steady state increased with dose, indicating Central Nervous System (CNS) exposure at relevant levels for pharmacodynamic effects. ACD856 demonstrated significant dose-dependent treatment-associated changes on qEEG parameters. Specifically, increase of the relative theta power and decrease of the fast alpha and beta power was observed, leading to an acceleration of the delta+theta centroid and an increase in the theta/beta ratio.

Conclusions

ACD856 was well tolerated at the tested dose levels (10–90 mg/daily for 7 days) in healthy subjects. The compound has a robust pharmacokinetic profile, with rapid absorption and dose-dependent exposure. ACD856 was shown to pass the blood-brain-barrier, reach relevant exposure in the CNS and to induce dose-dependent treatment-related changes on qEEG parameters, indicating central target engagement.

Följsamhet till nyinsatt behandling med ACE-hämmare/angiotensin II-antagonister och kalciumantagonister

Erik Örberg

Handledare Anders Ekedahl och Carola Bardage, Institutionen för farmaceutisk biovetenskap,avdelningen  för farmakoterapi och läkemedelsterapi 15hp. Examinator Margareta Hammarlund-Udenaes.

Introduktion: Bristande följsamhet leder till ökad mortalitet och morbiditet. Detta innebär stora kostnader för samhället. Följsamheten till långtidsbehandlingar antas vara omkring 50 % i Sverige.

Syfte: Att undersöka följsamheten till nyinsatt behandling med läkemedel inom ATC-grupperna C08 (kalciumantagonister) och C09 (ACE-hämmare och angiotensin II-antagonister)? Hur stor andel av läkemedelsanvändarna gör ett uttag respektive ≤4 uttag? Är det någon skillnad i följsamhet mellan användarna av läkemedel från ATC-grupp C08 och C09? Är det någon skillnad i följsamhet med avseende på kön och ålder?

Material: Deltagarna var de som gjorde minst ett uttag av läkemedel inom ATC-grupperna C08 och C09 under perioden 2011-01-01 till 2011-02-28. Dessa personers ytterligare uttag inom respektive ATC-grupp registrerades under två år. Deltagarna sorterades med avseende på kön och ålder (≤44, 45-64, 65-74, ≥75). Uppgifterna hämtades från Socialstyrelsens läkemedelsregister. För att beräkna statistiska skillnader användes Pearsons chi-II-test. 

Resultat: Ur ATC-grupp C08 var det 35,1 % av totalt 15584 personer som gjorde ≤4 uttag och 16,2 % gjorde endast ett uttag. Motsvarande resultat för ATC-grupp C09 var 23,7 % och 10,2 % av totalt 21484 personer. Kvinnor hade en signifikant högre andel som avslutade behandlingen än män. De yngsta och de äldsta hade en signifikant högre andel som avslutade behandlingen än de i åldrarna 45-64 och 65-74. Läkemedelsanvändarna i ATC-grupp C08 hade en signifikant högre andel som avslutade behandlingen än läkemedelsanvändarna i ATC-grupp C09.                      

Konklusion: Ytterligare studier behövs som kan förklara varför följsamheten skiljer sig mellan olika åldrar och mellan användarna av läkemedel inom de båda ATC-grupperna. Nästan hälften av alla som avslutade en behandling i förtid gjorde det inom tre månader, d.v.s. efter endast ett uttag.

Introduktion: Fibromyalgi är en sjukdom som är vanligare hos kvinnor än män. Cirka 2–4 % av Sveriges befolkning lider av sjukdomen och det är liknande siffror i andra delar av världen. För att få diagnosen fibromyalgi måste vissa kriterier uppfyllas, bland annat ska man ha en långvarig smärta i över tre månader. Även sömnbesvär och trötthet är vanliga besvär vid sjukdomen. I dagsläget finns det inga godkända läkemedel med indikationen fibromyalgi. Men vissa läkemedelsgrupper t.ex. tricykliska antidepressiva, antikonvulsiva och serotonin-noradrenalin återupptagshämmare har i kliniska studier visat god effekt hos patienter med fibromyalgi.

Syfte: Det är många som har fibromyalgi i Sverige men inget läkemedel med den indikationen finns. Därav syftet med studien, att jämföra behandling av fibromyalgi hos vuxna kvinnor med duloxetin, amitriptylin och/eller pregabalin.

Metod: En systematisk litteratursökning efter placebokontrollerade randomiserade studier och systematiska översikter gjordes i databaserna PubMed och Cochran samt via Läkemedelsverkets hemsida. De identifierade artiklarna kvalitetsgranskades enligt SBUs mallar för randomiserade studier respektive systematiska översikter.

Resultat: Totalt identifierades 4 artiklar som uppfyllde inklusionskriterierna. Av dessa dömdes 3 vara av medelhög kvalitet och 1 av låg kvalitet. I studierna visades att pregabalin och duloxetin hade, både i monoterapi och i kombination, en symtomlindrande effekt på smärtan hos patienter med fibromyalgi. Detta definierades som en sänkning med minst 40 mm på VAS-skalan. Ingen av de randomiserade kontrollerade studierna hade studerat amitriptylins effekter men den används idag framförallt mot sömnbesvär och tas i låg dos innan sänggående.

Konklusion: Det vetenskapliga underlaget är svagt och behöver stärkas, framförallt på symtomen sömn och trötthet hos fibromyalgipatienter.

Molecular modeling and inhibitory potencies of tetrapeptide protease inhibitors of HCV NS3 proposed phenylglycine as a new promising P2 residue. The results suggest that phenylglycine might be capable of interacting with the NS3 (protease-helicase/NTPase) in ways not possible for the common P2 proline-based inhibitors. Thus, a series of tripeptides, both linear and macrocyclic, based on p-hydroxy-phenylglycine in the P2 position were prepared and their inhibitory effect determined. When the p-hydroxy group was replaced by methoxy, isoquinolin-, or quinolinyloxy functions, inhibitors with improved potencies were obtained. The P2 phenylglycine-based inhibitors were further optimized by C-terminal extension to acyl sulfonamides and by P1–P3 cyclization, which gave products with inhibition constants in the nanomolar range (75 nM).

BACKGROUND: HCV infections are a serious threat to public health. An important drug target is the NS3 protease, for which several inhibitors are in clinical trials. Because of the high mutation rate of the virus, resistance against any HCV-specific drug is likely to become a substantial problem. Structure-activity data for the major resistant variants are therefore needed to guide future designs of protease inhibitors. METHODS: The inhibitory potency of tripeptide NS3 protease inhibitors, with either a P2 proline or phenylglycine, in combination with different P3 and P1-P1' groups, was assessed in enzyme activity assays using the full-length NS3 protein with known resistance-conferring substitutions A156T or D168V. The results obtained from these variants were compared with the inhibition of the wild-type enzyme. Molecular modelling was used to rationalize the biochemical results. RESULTS: Inhibitors combining the P2 proline and P1 (1R,2S)-1-amino-2-vinylcyclopropyl-carboxylic acid (vinylACCA) lost much of their potency on the resistant variants. Exchange of the P2 proline for phenylglycine yielded inhibitors that were equipotent on the wild-type and on the A156T and D168V variants. The same result was obtained from the combination of either the P2 residue with a norvaline or an aromatic scaffold in the P1 position. CONCLUSIONS: The combination of a substituted P2 proline and P1 vinylACCA appears to be the main problem behind the observed resistance. Molecular modelling suggests an enforced change in binding conformation for the P2 proline-based inhibitors, whereas the phenylglycine-based inhibitors retained their wild-type binding conformation in the substituted forms of the enzyme.

Less than 2% of the lead compounds generated by the pharmaceutical industry enter the exploratory drug-development phase, from which point they stand only a 10% chance of becoming a commercial medicine. A large proportion of the compounds fail due to poor biopharmaceutical properties, such as permeability and solubility. The main theme of this thesis is, therefore, the development of better experimental and computational methods for modelling and predicting the biopharmaceutical properties of drug candidates. Immobilised liposome chromatography (ILC) was used for studying drug-membrane interactions and for the prediction of passive drug transport. For the drugs studied in this thesis, ILC and octanol/water partitioning showed a similar performance with regard to the prediction of passive drug transport.

The theoretical work was directed at the modelling and prediction of drag transport processes using calculated molecular properties and PLS analysis. In the initial studies, the molecular properties were calculated with an advanced computational tool (MolSurf) that takes the three-dimensional structural information and electronic properties of the compound into consideration. Statistical models well suited to the prediction of drug transport processes such as Caco-2 cell permeability, intestinal absorption and CNS penetration were derived.

This approach was also successfully applied to the modelling of the interaction of drugs with P-glycoprotein. Subsequently, rapidly calculated descriptors based on two-dimensional structural information and PLS analysis were also found to give good predictive models of drug transport properties. The preferred use of the latter models is for screening compound collections and virtual libraries. It can be concluded that calculated molecular properties in conjunction with PLS analysis are well suited to the modelling and prediction of drug transport processes and to identifying compounds with potential biopharmaceutical problems at an early stage of the drug-development process.

beta-Carbolines show structural resemblance to the neurotoxic N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and are metabolized to mitochondrial toxicants. Humans are continuously exposed to low levels of beta-carbolines through cooked food, coffee, alcoholic beverages and tobacco smoke. beta-Carbolines have previously been detected in higher levels in the pigmented substantia nigra than in the cortex of humans. The distribution of 3H-labelled harman and norharman in the brain of pigmented and albino mice and in frogs (a species having neuromelanin) was studied by tape-section and light-microscopic autoradiography. Furthermore, the binding of these beta-carbolines to dopamine-melanin and melanin granules from Sepia officinalis was examined. The results revealed a high affinity binding to melanin and a long-term retention (up to 30 days) in pigmented tissues, including neuromelanin-containing neurons of frogs after a single injection. The role of long-term exposure to food-related beta-carbolines and a retention of these compounds in pigment-containing neurons in the induction of idiopathic Parkinson's disease should be further considered.

Cytogenetic lesions often alter kinase signaling in acute myeloid leukemia (AML) and the addition of kinase inhibitors to the treatment arsenal is of interest. We have screened a kinase inhibitor library and performed combination testing to find promising drug-combinations for synergistic killing of AML cells. Cytotoxicity of 160 compounds in the library InhibitorSelect (TM) 384-Well Protein Kinase Inhibitor I was measured using the fluorometric microculture cytotoxicity assay (FMCA) in three AML cell lines. The 15 most potent substances were evaluated for dose-response. The 6 most cytotoxic compounds underwent combination synergy analysis based on the FMCA readouts after either simultaneous or sequential drug addition in AML cell lines. The 4 combinations showing the highest level of synergy were evaluated in 5 primary AML samples. Synergistic calculations were performed using the combination interaction analysis package COMBIA, written in R, using the Bliss independence model. Based on obtained results, an iterative combination search was performed using the therapeutic algorithmic combinatorial screen (TACS) algorithm. Of 160 substances, cell survival was <= 50% at <0.5 mu M for Cdk/Crk inhibitor, KP372-1, synthetic fascaplysin, herbimycin A, PDGF receptor tyrosine kinase inhibitor IV and reference-drug cytarabine. KP372-1, synthetic fascaplysin or herbimycin A obtained synergy when combined with cytarabine in AML cell lines MV4-11 and HL-60. KP372-1 added 24 h before cytarabine gave similar results in patient cells. The iterative search gave further improved synergy between cytarabine and KP372-1. In conclusion, our in vitro studies suggest that combining KP372-1 and cytarabine is a potent and synergistic drug combination in AML.

The results from this thesis leads to the following conclusions; HUM is a useful tool that fills a gap in the in vitro methods previously available to study nasal drug delivery. Using HUM, the pig respiratory nasal mucosa can obtain acceptable viability and retain it longer than the period of time needed for a transport experiment. HUM has proven to be an appropriate tool for the study of liquids in low volume, gels, both unmodified and with controlled release properties, and particle suspensions. The potential local toxicity of formulations such as controlled release gels and surfactants could be evaluated and graded using HUM. The estimation of the apparent permeability can be corrected on a mathematical basis, for substances that bind to the chamber material. As seen using HUM, unmodified gels from Carbopol 934 (C934) are well tolerated by the nasal mucosa and may consequently be suitable for nasal administration. The release rate of testostenone, dihydroalprenolol and hydrocortisone from C934 gels can be successfully sustained. Protein-conjugated starch microparticles, intended to function as a vaccine carrier system, were taken up by non-ciliated epithelial cells of the pig respiratory nasal mucosa after incubation using HUM. The concentration-dependent effects on permeability and transepithelial electrical resistance on Caco-2 cells, of a series of nonionic polyoxyethylene surfactants, correlated with surfactant structure. Similar effects were seen on pig nasal mucosa using HUM, but the nasal mucosa appeared to be more tolerant to the surfactants than the intestinal cell model.

The nasal route has advantages for several classes of drugs e.g. involved in migrain treatment, nicotine substitution therapy and mucosal vaccination. The increased development of a variety of substances, in a variety of formulation types, has increased the demand for suitable investigational tools. It is in this context that the horizontal Ussing chamber method (HUM) was developed. Using HUM, the studied formulation can be applied on the mucosa without additional buffer, giving an in vivo-like situation and the possibility to study solid and semi-solid formulations. Furthermore, the influence of gravity will not result in uneven distribution of the formulation.

Background and objective: According to the Swedish board of health and welfare a patient should receive a discharge letter containing a medication report including information about all medication changes during the admission, and the reason behind them, at discharge. Hospital readmissions have been shown to correlate to poor compliance and mistakes following a lack of information regarding medication changes. This study aimed to improve a recently developed checklist (KU1) and use the new version (KU2) to measure the completeness of discharge documentation. This study was part of ongoing quality improvement projects at the geriatric- and internal medicine clinics. 

Study design and setting: This was a retrospective cross-sectional study where data from electronic medical records was reviewed. Patients admitted to two wards at Uppsala University hospital, 30A and 30E, in October 2021 aged 50 years or older and with at least one lasting medication change during the stay were eligible for inclusion. 

Method: The already existing checklist KU1 was updated along with an updated standard operating procedure (SOP). The new checklist, KU2, was used in the data collection to review and assess the completeness of patient journals with a score of 7 considered to be a complete discharge.

Results: A total of 80 patient journals (40 from each ward) were reviewed and assessed using the updated checklist, KU2. Across both wards, a total of 19 (23,8%) patient journals scored a perfect 7. This corresponded to 12 (30%) and 7 (17,5%) for 30A and 30E respectively. The most common criteria not being fulfilled in the checklist, was for both wards to miss mentioning at least one relevant change in the discharge summary. 

Conclusion: Most discharge documents reviewed in this study did not meet the requirements stated by Swedish law. There is a need for internal quality improvement initiatives as well as further studies in the field. 

The population pharmacokinetics of desmopressin in children with nocturnal enuresis and in healthy adults were compared using a 1-compartment model with first-order absorption and first-order elimination. In addition, the model consisted of a number of transit compartments before absorption to describe a lag-time. The model gave an adequate description of adult as well as children data and provided a statistically significant better fit to data than a standard lag-time model. The main difference in the pharmacokinetics between children and adults was the absorption delay. The pharmacokinetic difference was minor and presumably of no clinical relevance.