Experiences and Translatability of In Vitro and In Vivo Models to Evaluate Caprate as a Permeation Enhancer

Transient permeation enhancers (PEs) have been widely used to improve the oral absorption of macromolecules. During pharmaceutical development, the correct selection of the macromolecule, PE, and the combination needs to be made to maximize oral bioavailability and ensure successful clinical development. Various in vitro and in vivo methods have been investigated to optimize this selection. In vitro methods are generally preferred by the pharmaceutical industry to reduce the use of animals according to the "replacement, reduction, and refinement" principle commonly termed "3Rs," and in vitro methods typically have a higher throughput. This paper compares two in vitro methods that are commonly used within the pharmaceutical industry, being Caco-2 and an Ussing chamber, to two in vivo models, being in situ intestinal instillation to rats and in vivo administration via an endoscope to pigs. All studies use solution formulation of sodium caprate, which has been widely used as a PE, and two macromolecules, being FITC-dextran 4000 Da and MEDI7219, a GLP-1 receptor agonist peptide. The paper shares our experiences of using these models and the challenges with the in vitro models in mimicking the processes occurring in vivo. The paper highlights the need to consider these differences when translating data generated using these in vitro models for evaluating macromolecules, PE, and combinations thereof for enabling oral delivery.

Evaluation in pig of an intestinal administration device for oral peptide delivery

The bioavailability of peptides co-delivered with permeation enhancers following oral administration remains low and highly variable. Two factors that may contribute to this are the dilution of the permeation enhancer in the intestinal fluid, as well as spreading of the released permeation enhancer and peptide in the lumen by intestinal motility. In this work we evaluated an Intestinal Administration Device (IAD) designed to reduce the luminal dilution of drug and permeation enhancer, and to minimize movement of the dosage form in the intestinal lumen. To achieve this, the IAD utilizes an expanding design that holds immediate release mini tablets and places these in contact with the intestinal epithelium, where unidirectional drug release can occur. The expanding conformation limits movement of the IAD in the intestinal tract, thereby enabling drug release at a single focal point in the intestine. A pig model was selected to study the ability of the IAD to promote intestinal absorption of the peptide MEDI7219 formulated together with the permeation enhancer sodium caprate. We compared the IAD to intestinally administered enteric coated capsules and an intestinally administered solution. The IAD restricted movement of the immediate release tablets in the small intestine and histological evaluation of the mucosa indicated that high concentrations of sodium caprate were achieved. Despite significant effect of the permeation enhancer on the integrity of the intestinal epithelium, the bioavailability of MEDI7219 was of the same order of magnitude as that achieved with the solution and enteric coated capsule formulations (2.5-3.8%). The variability in plasma concentrations of MEDI7219 were however lower when delivered using the IAD as compared to the solution and enteric coated capsule formulations. This suggests that dosage forms that can limit intestinal dilution and control the position of drug release can be a way to reduce the absorptive variability of peptides delivered with permeation enhancers but do not offer significant benefits in terms of increasing bioavailability.

Intestinal Absorption of FITC-Dextrans and Macromolecular Model Drugs in the Rat Intestinal Instillation Model

In this work, we studied the intestinal absorption of a peptide with a molecular weight of 4353 Da (MEDI7219) and a protein having a molecular weight of 11 740 Da (PEP12210) in the rat intestinal instillation model and compared their absorption to fluorescein isothiocyanate (FITC)-labeled dextrans of similar molecular weights (4 and 10 kDa). To increase the absorption of the compounds, the permeation enhancer sodium caprate (C10) was included in the liquid formulations at concentrations of 50 and 300 mM. All studied compounds displayed an increased absorption rate and extent when delivered together with 50 mM C10 as compared to control formulations not containing C10. The time period during which the macromolecules maintained an increased permeability through the intestinal epithelium was approximately 20 min for all studied compounds at 50 mM C10. For the formulations containing 300 mM C10, it was noted that the dextrans displayed an increased absorption rate (compared to 50 mM C10), and their absorption continued for at least 60 min. The absorption rate of MEDI7219, on the other hand, was similar at both studied C10 concentrations, but the duration of absorption was extended at the higher enhancer concentration, leading to an increase in the overall extent of absorption. The absorption of PEP12210 was similar in terms of the rate and duration at both studied C10 concentrations. This is likely caused by the instability of this molecule in the intestinal lumen. The degradation decreases the luminal concentrations over time, which in turn limits absorption at time points beyond 20 min. The results from this study show that permeation enhancement effects cannot be extrapolated between different types of macromolecules. Furthermore, to maximize the absorption of a macromolecule delivered together with C10, prolonging the duration of absorption appears to be important. In addition, the macromolecule needs to be stable enough in the intestinal lumen to take advantage of the prolonged absorption time window enabled by the permeation enhancer.

A37 EFFICACY AND SAFETY OF RISANKIZUMAB AS MAINTENANCE THERAPY IN PATIENTS WITH CROHN’S DISEASE: 52 WEEK RESULTS FROM THE PHASE 3 FORTIFY STUDY

Background

Risankizumab (RZB), an anti-IL-23 p19 inhibitor, was well-tolerated and superior to placebo (PBO) in inducing clinical remission and endoscopic response in patients (pts) with moderate-to-severe Crohn’s disease (CD) in two phase 3 studies at 12 weeks.

Aims

FORTIFY (NCT03105102), was a 52-week (wk) phase 3 double-blind, re-randomized responder withdrawal study that evaluated the efficacy and safety of continuing RZB as subcutaneous (SC) maintenance therapy versus withdrawal to placebo in pts achieving induction response to RZB

Methods

Week 12 IV RZB responders were re-randomized 1:1:1 to: RZB SC 360mg (N=141), RZB 180mg (N=157), or PBO (withdrawal from IV RZB; N=164) every 8wks for 52wks. Co-primary endpoints were clinical remission (per CD Activity Index [CDAI] (US); or stool frequency/abdominal pain score [SF/APS] (OUS) and endoscopic response at wk52. Other clinical and endoscopic endpoints, inflammatory biomarkers, RZB serum levels, and safety were assessed over time.

Results

Rates of clinical remission (CDAI, SF/APS) and clinical response were similar for RZB and PBO groups through wk24, with rates lower for PBO thereafter. At wk52, clinical remission (CDAI, SF/APS) and endoscopic response rates were significantly higher with RZB 360mg than PBO ( P<0.01); RZB 180mg was superior to PBO for clinical remission per CDAI and endoscopic response ( P<0.01). Endoscopic remission and deep remission rates increased over time with 360mg, remained steady with 180mg, and decreased with PBO. Mean fecal calprotectin (FCP) and C-reactive protein (CRP) levels decreased with SC RZB, but increased with PBO, over 52wks. Exposure-adjusted event rates (per 100 pts-years) of serious adverse event (AE) were generally similar among groups (360mg, 21.0 E/100PY and 180mg, 19.5 E/100PY vs PBO, 19.3 E/100PY), as were AEs leading to drug discontinuation (4.8 E/100PY and 2.4 E/100PY vs 3.7 E/100PY), and serious infections (6.0 E/100PY and 3.0 E/100PY vs 5.0 E/100PY).

Conclusions

In pts with moderate-to-severe CD, a robust pharmacodynamic effect on the IL-23 pathway after 12wks RZB IV induction was maintained with RZB SC maintenance therapy. The durability of RZB was demonstrated with high rates of efficacy over the 52-wk study. RZB was superior to PBO for achieving clinical remission and endoscopic response at wk52. Results for the more stringent endpoints (endoscopic remission\deep remission) and persistent improvements in inflammatory biomarkers are consistent with a dose response relationship. Continued RZB SC maintenance treatment was generally safe and well-tolerated.

Funding Agencies

AbbVie

Severe multisystem inflammatory syndrome (MIS-C/A) after confirmed SARS-CoV-2 infection: a report of four adult cases

BACKGROUND

Multisystem inflammatory syndrome (MIS) triggered by a recent SARS-Cov-2 infection has been recognised worldwide. Although predominantly affecting children (MIS-C), similar presentations have been reported among adults (MIS-A).

METHOD

A retrospective case series describing four critically ill patients with MIS-C/A diagnosed between January and April 2021 at Sahlgrenska University Hospital, Gothenburg, Sweden. Clinical presentation, laboratory and radiological findings, treatment and outcome are reported.

RESULTS

Cases occurred in previously healthy patients with a history of laboratory-confirmed mild SARS-CoV-2 infection four to seven weeks earlier. The median age was 24 years (range 19-43) and 3/4 were male. All fulfilled suggested MIS-C/A criteria according to the US Centre for Disease Control and all required care at an intensive care unit. Treatment was initiated with intravenous immunoglobulin, interleukin-1-receptor antagonists, and pulse steroids in 3/4 cases which resulted in rapid clinical improvement. No severe complications were noticed in any case during a three-month follow-up period.

CONCLUSION

MIS-C/A should be considered, irrespective of age, in patients with fever, hyperinflammation and multiple organ system involvements emerging weeks after COVID-19. Previously suggested treatment regimens for MIS-C seem to be applicable also for MIS-A.

Impact of Intestinal Concentration and Colloidal Structure on the Permeation-Enhancing Efficiency of Sodium Caprate in the Rat

In this work, we set out to better understand how the permeation enhancer sodium caprate (C10) influences the intestinal absorption of macromolecules. FITC-dextran 4000 (FD4) was selected as a model compound and formulated with 50–300 mM C10. Absorption was studied after bolus instillation of liquid formulation to the duodenum of anesthetized rats and intravenously as a reference, whereafter plasma samples were taken and analyzed for FD4 content. It was found that the AUC and C_max of FD4 increased with increasing C10 concentration. Higher C10 concentrations were associated with an increased and extended absorption but also increased epithelial damage. Depending on the C10 concentration, the intestinal epithelium showed significant recovery already at 60–120 min after administration. At the highest studied C10 concentrations (100 and 300 mM), the absorption of FD4 was not affected by the colloidal structures of C10, with similar absorption obtained when C10 was administered as micelles (pH 8.5) and as vesicles (pH 6.5). In contrast, the FD4 absorption was lower when C10 was administered at 50 mM formulated as micelles as compared to vesicles. Intestinal dilution of C10 and FD4 revealed a trend of decreasing FD4 absorption with increasing intestinal dilution. However, the effect was smaller than that of altering the total administered C10 dose. Absorption was similar when the formulations were prepared in simulated intestinal fluids containing mixed micelles of bile salts and phospholipids and in simple buffer solution. The findings in this study suggest that in order to optimally enhance the absorption of macromolecules, high (≥100 mM) initial intestinal C10 concentrations are likely needed and that both the concentration and total dose of C10 are important parameters.

Discriminatory accuracy of the SOFA score for determining clinical decompensation in patients presenting with COVID-19

Introduction

While the global dissemination of vaccines targeting the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in a decline in the incidence of infections, the case fatality rates have remained relative stable. A major objective of managing hospitalized patients with documented or suspected COVID-19 infection is the rapid identification of features associated with severe illness using readily available laboratory tests and clinical tools. The sequential organ failure assessment (SOFA) score is a validated tool to facilitate the identification of patients at risk of dying from sepsis.

Purpose

The aim of this study was to assess the discriminatory accuracy of the SOFA score in predicting clinical decompensation in patients hospitalized with COVID-19 infection.

Methods

We conducted a retrospective analysis at a three-hospital health system, comprised of one tertiary and two community hospitals, located in the Chicago metropolitan area. All patients had positive SARS-CoV-2 testing and were hospitalized for COVID-19 infection. The primary outcome was clinical decompensation, defined as the composite endpoint of death, ICU admission, or need for intubation. We utilized the most abnormal laboratory values observed during the admission to calculate the SOFA score. Receiver Operating Curves (ROC) were then constructed to determine the sensitivity and specificity of SOFA scores.

Results

Between March 1st and May 31st 2020, 1029 patients were included in our analysis with 367 patients meeting the study endpoint. The median SOFA score was 2.0 IQR (Q1, Q3 1,4) for the entire cohort. Patients who had in-hospital mortality had a median SOFA score of 4.0 (Q1,Q3 3,7). In patients that met the primary composite endpoint, the median SOFA score was 3.0, IQR (Q1, Q3 2,6). The ROC was 0.776 (95% CI 0.746–0.806, p<0.01).

Conclusion

The SOFA score demonstrates strong discriminatory accuracy for prediction of clinical decompensation in patients presenting with COVID-19 at our urban hospital system.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): Loyola University Medical Center

Predictors of clinical decompensation in patients presenting with COVID-19 in an urban hospital health system

Introduction

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in a pandemic which has infected more than 128 million people and led to over 2.8 million deaths worldwide. Although the introduction of efficacious vaccines has led to overall declines in the incidence of SARS-CoV-2 infection, there has been a recent increase in infections once more due to the appearance of mutant strains with higher virulence. It therefore remains vital to identify predictors of poor outcomes in this patient population.

Purpose

The objective of our study was to identify predictors of prolonged hospitalization, intensive care unit (ICU) admission, intubation, and death in patients infected with SARS-CoV-2.

Methods

We conducted a retrospective analysis of all patients hospitalized with SARS-CoV-2 at our health system that includes one tertiary care center and two community hospitals located in the Chicago metropolitan area. The main outcome was a composite endpoint of hospitalization >28 days, ICU admission, intubation, and death.

Explanatory variables associated with the primary outcome in the bivariate analysis (p<0.05) were included in the multivariable logistic regression model. Statistical analysis was performed using IBM SPSS 25.0.

Results

Between March 1, 2020 and May 31, 2020, 1029 patients hospitalized with SARS-CoV-2 were included in our analysis. Of these patients, 379 met the composite endpoint. Baseline demographics are described in Table 1. Of note, our cohort consisted of a predominantly minority patient population including 47% Hispanic, 17% African American, 16% Caucasian, and 16% other.

In bivariate analysis, age, hypertension, tobacco and alcohol abuse, obesity, coronary artery disease, arrhythmias, valvular heart disease, dyslipidemia, hypertension, stroke, diabetes, documented thrombosis, troponin, CRP, ESR, ferritin, LDH, BNP, D-dimer >5x the upper limit of normal, lactate, and right ventricular outflow tract velocity time integral <9.5 were significant.

After multivariable adjustment, explanatory variables associated with the composite endpoint included troponin (OR 2.36; 95% CI 1.08–5.17, p 0.03), D-dimer (OR 1.5; 95% CI 1.23–1.98, p<0.01, lactate (OR 1.58; 95% CI 1.28–1.95, p<0.01), and documented thrombosis (OR 3.56; 95% CI 1.30–8.70, p<.05). Race was not a predictor of poor outcomes in the bivariate or multivariate analysis (Table 2).

Conclusions

In a large urban cohort with a predominantly minority population, we identified several clinical predictors of poor outcomes. Of note, race was not a predictor of the primary endpoint in this study. While recent literature has demonstrated worse outcomes among racial minorities infected with SARS-CoV-2, our data suggests these variations are related to social determinants of health rather than biologic causes.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): Loyola University Medical Center

Microbiological colonization of peripheral venous catheters: a prospective observational study in a Swedish county hospital

Background

Most peripheral venous catheters (PVCs) used in Scandinavia are fitted with an injection port, creating an open PVC system. This port is difficult to disinfect, which may lead to the introduction of micro-organisms upon use.

Aim

To investigate the prevalence of microbiological colonization of the injection port and internal lumen of ported PVCs with a minimum dwell time of 48 h at sample collection.

Methods

Adult patients admitted to different medical and surgical departments and the intensive care unit were invited to participate in this prospective observational study. With the PVC in situ, the injection port and internal lumen were swabbed and cultured separately. Demographic and clinical data were collected to compare patients with colonized and non-colonized PVCs.

Findings

In total, 300 PVCs from 300 patients were analysed. Of these, 33 patients (11.0%) had at least one positive culture. The colonization locations were as follows: port only, 26 (8.7%); internal lumen only, 5 (1.7%); and port and internal lumen, 2 (0.7%). The colonization rate was significantly higher in the injection port than in the internal lumen (P<0.0001). A ported PVC inserted in the hand incurred a significant risk of colonization (P=0.03). The odds ratio for colonization among patients in the infectious diseases department was 0.1 (95% confidence interval 0.1–1; P<0.06) compared with patients in the medical department.

Conclusion

This study showed that 11% of ported PVCs were colonized by micro-organisms, with the vast majority (8.7%) of colonization occurring in the injection port.

Clinical trial registration

ClinicalTrials.gov; ID NCT03351725.

Association of clinical factors and recent anticancer therapy with COVID-19 severity among patients with cancer: a report from the COVID-19 and Cancer Consortium

BACKGROUND

Patients with cancer may be at high risk of adverse outcomes from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We analyzed a cohort of patients with cancer and coronavirus 2019 (COVID-19) reported to the COVID-19 and Cancer Consortium (CCC19) to identify prognostic clinical factors, including laboratory measurements and anticancer therapies.

PATIENTS AND METHODS

Patients with active or historical cancer and a laboratory-confirmed SARS-CoV-2 diagnosis recorded between 17 March and 18 November 2020 were included. The primary outcome was COVID-19 severity measured on an ordinal scale (uncomplicated, hospitalized, admitted to intensive care unit, mechanically ventilated, died within 30 days). Multivariable regression models included demographics, cancer status, anticancer therapy and timing, COVID-19-directed therapies, and laboratory measurements (among hospitalized patients).

RESULTS

A total of 4966 patients were included (median age 66 years, 51% female, 50% non-Hispanic white); 2872 (58%) were hospitalized and 695 (14%) died; 61% had cancer that was present, diagnosed, or treated within the year prior to COVID-19 diagnosis. Older age, male sex, obesity, cardiovascular and pulmonary comorbidities, renal disease, diabetes mellitus, non-Hispanic black race, Hispanic ethnicity, worse Eastern Cooperative Oncology Group performance status, recent cytotoxic chemotherapy, and hematologic malignancy were associated with higher COVID-19 severity. Among hospitalized patients, low or high absolute lymphocyte count; high absolute neutrophil count; low platelet count; abnormal creatinine; troponin; lactate dehydrogenase; and C-reactive protein were associated with higher COVID-19 severity. Patients diagnosed early in the COVID-19 pandemic (January-April 2020) had worse outcomes than those diagnosed later. Specific anticancer therapies (e.g. R-CHOP, platinum combined with etoposide, and DNA methyltransferase inhibitors) were associated with high 30-day all-cause mortality.

CONCLUSIONS

Clinical factors (e.g. older age, hematological malignancy, recent chemotherapy) and laboratory measurements were associated with poor outcomes among patients with cancer and COVID-19. Although further studies are needed, caution may be required in utilizing particular anticancer therapies.

CLINICAL TRIAL IDENTIFIER

NCT04354701.

Transthyretin amyloid deposits in lumbar spinal stenosis and assessment of signs of systemic amyloidosis

BACKGROUND

Wild-type transthyretin (ATTRwt) amyloidosis is the most common systemic amyloidosis in Western countries and manifests mainly as progressive restrictive cardiomyopathy.

OBJECTIVE

To study the prevalence of ATTR deposits in ligament tissue in patients undergoing surgery for lumbar spinal stenosis and to assess whether these deposits are associated with cardiac amyloidosis.

MATERIALS AND METHODS

A total of 250 patients, aged 50-89 (57% women), none with known cardiovascular disease, were included. Ligaments were investigated microscopically for amyloid. ATTR type was determined by immunohistochemistry and fibril type by Western blot. The amount of amyloid was graded 0-4. All patients with grade 3-4 ATTR deposits were offered cardiac investigation including ECG, cardiac ultrasound, plasma NT-proBNP and cardiac magnetic resonance (CMR), including modern tissue characterization.

RESULTS

Amyloid was identified in 221 of the samples (88.4%). ATTR appeared in 93 samples (37%) of whom 42 (17 women and 25 men) were graded 3-4; all had fibril type A (mixture of full-length TTR and fragmented TTR). Twenty-nine of 42 patients with grade 3-4 ATTR deposits accepted cardiovascular investigations; none of them had definite signs of cardiac amyloidosis, but five men had a history of carpal tunnel syndrome.

CONCLUSIONS

The prevalence of ATTR deposits in ligamentum flavum in patients with lumbar spinal stenosis was high but not associated with manifest ATTR cardiac amyloidosis. However, the findings of fibril type A, the prevalence of previous carpal tunnel syndrome and ATTR amyloid in surrounding adipose and vascular tissue indicate that amyloid deposits in ligamentum flavum may be an early manifestation of systemic ATTR disease.

In Vitro and In Vivo Evaluation of 3D Printed Capsules with Pressure Triggered Release Mechanism for Oral Peptide Delivery

In this study a 3D printed capsule designed to break from the physiological pressures in the antropyloric region was evaluated for its ability to deliver the synthetic octapeptide octreotide in beagle dogs when co-formulated with the permeation enhancer sodium caprate. The pressure sensitive capsules were compared to traditional enteric coated hard gelatin capsules and enteric coated tablets. Paracetamol, which is completely absorbed in dogs, was included in the formulations and used as an absorption marker to give information about the in vivo performance of the dosage forms. The pressure sensitive capsules released drug in 50% of the dogs. In the cases where drug was released, there was no difference in octreotide bioavailability or C_max compared to the enteric coated dosage forms. When comparing all dosage forms, a correlation was seen between paracetamol C_max and octreotide bioavailability, suggesting that a high drug release rate may be beneficial for peptide absorption when delivered together with sodium caprate.

Correction to: Development of a new reproductive tissue cryopreservation clinical service for children: the Oxford programme

In the published version, the Acknowledgements section was missing a funding note of co-author Dr C Verrill. The corrected version should read as follows.

Liquid Chromatographic Determination of Ochratoxin A in Barley, Wheat Bran, and Rye by the AOAC/IUPAC/NMKL Method: NMKL Collaborative Study1

In an inter laboratory study of the AOAC/lnternational Union of Pure and Applied Chemistry (IUPAC)/ Nordic Committee on Food Analysis (NMKL) liquid chromatographic method for ochratoxin A (OTA), 3 spiked samples each of wheat bran and rye and 3 naturally contaminated barley samples with expected OTA contents between 2 and 9 μg/kg were analyzed by 12 European laboratories. Mean recoveries ranged from 64 to 72%. Within-laboratory standard deviations were 21,17, and 12% for wheat bran, rye, and barley, respectively. Corresponding between-laboratory standard deviations were 23-28,20-28, and 18-31%. Horwitz ratio values ranged from 0.50 to 0.77. The method was accepted as an official NMKL method for determining OTA at ≥2 μg/kg in cereals and cereal products.

Penile Paget's Disease: A Case Report and Review of the Literature

Extramammary Paget's Disease (EMPD) is a rare cutaneous, slow growing, intraepithelial adenocarcinoma that can be either primary (intraepithelial arising within the epidermis) or secondary (intraepithelial spread of a visceral carcinoma). Here we present the case of a 63-year-old male with EMPD of the glans penis stemming from underlying urothelial carcinoma. Our treatment decision elected for management with chemotherapy and local treatment with radiation therapy. Subsequent, review of the literature demonstrated a rare disease with a variety of underlying malignancies causing this secondary pathology. Caregivers should be aware of the association of Paget's disease and urothelial cancer and should have a high index of suspicion that erythematous penile lesions may represent Paget's disease and that penile biopsies should be performed early in this setting.

Development of a new reproductive tissue cryopreservation clinical service for children: the Oxford programme

PURPOSE

This article describes the development of a new reproductive tissue cryopreservation clinical service for children at high risk of infertility in the NHS during times of severe financial constraints in the health service.

METHOD

A development plan with two phases was drawn up. Phase 1 restricted the service to childhood cancer patients referred to the Oxford Paediatric Oncology and Haematology Principle Treatment Centre. It was estimated that there would be 10 patients/year and used existing staff and facilities from paediatric oncology, surgery, anaesthetics radiology, pathology, psychology, teenage-young adult gynaecology, and an existing Human Tissue Authority tissue bank with a licence for storage of tissue under a Human Sector Licence. Phase 2 extended the service to include children and young adults across England, Wales and Ireland-patients from Scotland having access to a research programme in Edinburgh. The main challenge in phase 2 being resources and the need for patients to be able to be treated as close to home as safely as possible.

RESULTS

The Oxford team developed information resources and eligibility criteria based on published best practice, referral and treatment pathways, multidisciplinary team meetings, a network of third party sites, and a dedicated case management and database. As the programme expanded, the Oxford team was able to justify to management the need for a dedicated theatre list. Patient feedback through questionnaires, qualitative work conducted as part of a Ph.D. thesis as well as direct patient stories and interviews in TV, and radio features underpins the positive impact the programme has on patients and their families.

CONCLUSION

The Oxford Reproductive Cryopreservation programme delivers fertility preservation treatment to children and young adults at high risk of infertility safely, effectively and as close to home as possible. The onward view is to apply for national funding for this programme for recognition and sustainability.

Activated platelet aggregation is transiently impaired also by a reduced dose of protamine

Objectives: Protamine reduces platelet aggregation after cardiopulmonary bypass (CPB). We studied the inhibitory effect of a reduced protamine dose, the duration of impaired platelet function and the possible correlation to postoperative bleeding. Design: Platelet function was assessed by impedance aggregometry in 30 patients undergoing cardiac surgery with CPB at baseline, before protamine administration, after 70% and 100% of the calculated protamine dose, after 20 minutes and at arrival to the intensive care unit. Adenosine diphosphate (ADP), thrombin receptor activating peptide-6 (TRAP), arachidonic acid (AA) and collagen (COL) were used as activators. Blood loss was measured during operation and three hours after surgery. Results are presented as median (25th-75th percentile). Results: Platelet aggregation decreased markedly after the initial dose of protamine (70%) with all activators; ADP 89 (71-110) to 54 (35-78), TRAP 143 (116-167) to 109 (77-136), both p < .01; AA 25 (16-49) to 17 (12-24) and COL 92 (47-103) to 60 (38-81) U, both p < .05. No further decrease was seen after 100% protamine. The effect was transient and after twenty minutes platelet aggregation had started to recover; ADP 76 (54-106), TRAP 138 (95-158), AA 20 (10-35), COL 70 (51-93) U. Blood loss during operation correlated to aggregometry measured at baseline and after protaminization. Conclusions: Protamine after CPB induces a marked decrease in platelet aggregation already at a protamine-heparin ratio of 0.7:1. The impairment seems to be transient and recovery had started after 20 minutes.

From uncertainty to gradually managing and awaiting recovery of a periodic condition- a qualitative study of parents´ experiences of PFAPA syndrome

BACKGROUND

The prevalence of periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis (PFAPA) syndrome is unknown. Although an uncommon condition, it is considered to be the most common autoinflammatory disease among children in many parts of the world. The knowledge of the consequences of the recurrent fever episodes for the child and its family are limited. This study explores the experiences of parents regarding the impact of the disease on the child's general well-being, the family's situation and how the family handles the associated challenges.

METHODS

A qualitative approach was used, applying a modified version of Grounded theory for design, data collection and analysis. Data was collected from two different sources: communication between parents of children with PFAPA in a closed Facebook group and face-to face interviews with one of the parents of children diagnosed with PFAPA (6 mothers and 2 fathers).

RESULTS

Parents described a lengthy process of how everyday life becomes affected by their child's recurrent fever episodes. This process is depicted in the following Grounded Theory core category: From uncertainty to gradually managing and awaiting recovery. The categories Uncertainty, Assurance, Gradually managing and Recovery describe the experienced illness trajectory. The illness representation illustrates the experiences/impacts of the periodic condition in the subcategories: Harmlessness-Severity, Disclosure of diagnosis, Impact on daily life and Regularity-Unpredictability. The children's well-being was highly affected by the symptoms during episodes. Parents experienced increased stress with constant fatigue, social constraints of family life and restricted career opportunities. Nevertheless, hope of recovery was constantly present.

CONCLUSIONS

PFAPA is associated with a considerable burden on the child and the parents in daily life. Obtaining a diagnosis enables parents to move from a state of uncertainty towards a sense of coherence while awaiting recovery. Because of limited general knowledge of the condition and its impact on daily life, health care professionals need to become aware of the parents' efforts to mitigate the consequences of the recurrent episodes for the child and for the family as a whole.

Aggregation Behavior of Medium Chain Fatty Acids Studied by Coarse-Grained Molecular Dynamics Simulation

Medium chain fatty acids (MCFA) are digestion products of lipid-rich food and lipid-based formulations, and they are used as transient permeability enhancers in formulation of poorly permeable compounds. These molecules may promote drug absorption by several different processes, including solubilization, increased membrane fluidity, and increased paracellular transport through opening of the tight junctions. Therefore, understanding the aggregation behavior of MCFAs is important. A number of studies have measured the critical micelle concentration (CMC) of MCFAs experimentally. However, CMC is highly dependent on system conditions like pH, temperature, and the ionic strength of the buffer used in different experimental techniques. In this study, we investigated the aggregation behavior of four different MCFAs using the coarse-grained molecular dynamics (CG-MD) simulations with the purpose to explore if CG-MD can be used to study MCFA interactions occurring in water. The ratio of deprotonated and non-charged MCFA molecules were manipulated to assess aggregation behavior under different pH conditions and within the box sizes of 22 × 22 × 44 nm³ and 44 nm³ for 1 μs. CMCs were calculated by performing CG-MD simulations with an increasing number of MCFAs. The resulting aggregate size distribution and number of free MCFA molecules were used to determine the CMC. The CMCs from simulations for C₈, C₁₀, and C₁₂ were 1.8–3.5-fold lower than the respective CMCs determined experimentally by the Wilhelmy method. However, the variation of MCFA aggregate sizes and morphologies at different pH conditions is consistent with previous experimental observation. Overall, this study suggests that CG-MD is suitable for studying colloidal systems including various MCFAs.

Patient-Centered Interventions to Improve Adherence to Statins: A Narrative Synthesis of Systematically Identified Studies

Poor adherence to statins increases cardiovascular disease risk. We systematically identified 32 controlled studies that assessed patient-centered interventions designed to improve statin adherence. The limited number of studies and variation in study characteristics precluded strict quality criteria or meta-analysis. Cognitive education or behavioural counselling delivered face-to-face multiple times consistently improved statin adherence compared with control groups (7/8 and 3/3 studies, respectively). None of four studies using medication reminders and/or adherence feedback alone reported significantly improved statin adherence. Single interventions that improved statin adherence but were not conducted face-to-face included cognitive education in the form of genetic test results (two studies) and cognitive education via a website (one study). Similar mean adherence measures were reported for 17 intervention arms and were thus compared in a sub-analysis: 8 showed significantly improved statin adherence, but effect sizes were modest (+7 to +22 % points). In three of these studies, statin adherence improved despite already being high in the control group (82-89 vs. 57-69 % in the other studies). These three studies were the only studies in this sub-analysis to include cognitive education delivered face-to-face multiple times (plus other interventions). In summary, the most consistently effective interventions for improving adherence to statins have modest effects and are resource-intensive. Research is needed to determine whether modern communications, particularly mobile health platforms (recently shown to improve medication adherence in other chronic diseases), can replicate or even enhance the successful elements of these interventions while using less time and fewer resources.

Mechanisms of vortices termination in the cardiac muscle

We propose a solution to a long-standing problem: how to terminate multiple vortices in the heart, when the locations of their cores and their critical time windows are unknown. We scan the phases of all pinned vortices in parallel with electric field pulses (E-pulses). We specify a condition on pacing parameters that guarantees termination of one vortex. For more than one vortex with significantly different frequencies, the success of scanning depends on chance, and all vortices are terminated with a success rate of less than one. We found that a similar mechanism terminates also a free (not pinned) vortex. A series of about 500 experiments with termination of ventricular fibrillation by E-pulses in pig isolated hearts is evidence that pinned vortices, hidden from direct observation, are significant in fibrillation. These results form a physical basis needed for the creation of new effective low energy defibrillation methods based on the termination of vortices underlying fibrillation.

Vaccination of calves with Mycobacterium bovis Bacillus Calmette-Guerin reduces the frequency and severity of lesions of bovine tuberculosis under a natural transmission setting in Ethiopia

Bovine tuberculosis (bTB) is highly prevalent in intensive dairy farms of the urban "milk-sheds" in Ethiopia, and vaccination could be a cost-effective disease control strategy. In the present study, the efficacy of Bacillus Calmette-Guerin (BCG) to protect against bTB was assessed in Holstein-Friesian calves in a natural transmission setting. Twenty-three 2-week-old calves were subcutaneously vaccinated with BCG Danish SSI strain 1331, and matched 26 calves were injected with placebo. Six weeks later, calves were introduced into a herd of M. bovis-infected animals (reactors) and kept in contact with them for 1 year. In vitro and in vivo immunological tests were performed to assess immune responses post-vaccination and during exposure. Successful vaccine uptake was confirmed by tuberculin skin test and IFN-γ responses in vaccinated calves. The kinetics of IFN-γ responses to early secretory antigen target 6 and culture filtrate protein 10 (ESAT6 and CFP10, respectively) and tuberculin skin test responses post-exposure suggested that the animals were infected early after being placed in contact with the infected herd as immunological signs of infection were measurable between 2 and 4 months post-initial exposure. Protection was determined by comparing gross and microscopic pathology and bacteriological burden between vaccinated and control calves. BCG vaccination reduced the proportions of tissues with visible pathology in vaccinates compared to control calves by 49% (p < .001) with 56%, 43%, 72%, and 38% reductions in the proportion of lesioned tisues in head, thoracic, abdominal lymph nodes, and lungs, respectively (p-values .029-.0001). In addition, the lesions were less severe grossly and microscopically in vaccinated calves than in non-vaccinated calves (p < .05). The reduction in the overall incidence rates of bTB was 23%, 28%, and 33% on the basis of the absence of gross pathology, M. bovis culture positivity, and histopathology, respectively, in vaccinated animals. In conclusion, BCG vaccination reduced the frequency and severity of the pathology of bTB significantly, which is likely to reduce onwards transmission of the disease.

Primary Porcine Brain Endothelial Cells as In Vitro Model to Study Effects of Ultrasound and Microbubbles on Blood-Brain Barrier Function

Focused ultrasound (FUS) in the presence of microbubbles transiently and reversibly opens the blood-brain barrier (BBB) in rodents and humans, thereby providing a time window for increased drug delivery into brain tissue. To get insight into the underlying mechanisms that govern ultrasound (US)-mediated opening of the BBB, in vitro models are a useful alternative. In this paper, we have utilized an in vitro BBB model that consists of primary porcine brain endothelial cells (PBECs). PBEC monolayers are grown on permeable membranes, which allow assessment of key features of BBB function as well as US treatment. This experimental model is characterized by low permeability for both small molecules and proteins, has a high transendothelial electrical resistance, and expresses tight junctions and efflux pumps. Here, we compare the effects of inertial and stable cavitation in the presence of SonoVue microbubbles on PBEC monolayers' electrical resistance and permeability properties. Our results point out the fragility of PBEC monolayers, which enhances results variability. In particular, we show that handling of the inserts, such as medium change and transfer to the US setup, modifies the cellular response, and immunostaining of the monolayers introduces damage and cell detachment within the US-exposed monolayers. Our results indicate that stable cavitation might have a more pronounced impact on cell permeability as compared with inertial cavitation in vitro. This paper might contribute to further development of experimental setups that are suitable to characterize the impact of FUS and microbubbles on BBB properties in vitro.

Probing adsorption of DSPE-PEG2000 and DSPE-PEG5000 to the surface of felodipine and griseofulvin nanocrystals

Nanosized formulations of poorly water-soluble drugs show great potential due to improved bioavailability. In order to retain colloidal stability, the nanocrystals need to be stabilized. Here we explore the use of the poly(ethylene glycol) (PEG) conjugated phospholipids DSPE-PEG2000 and DSPE-PEG5000 as stabilizers of felodipine and griseofulvin nanocrystals. Nanocrystal stability and physicochemical properties were examined and the interaction between the PEGylated lipids and the nanocrystal surface as well as a macroscopic model surface was investigated. Using quartz crystal microbalance with dissipation monitoring both mass adsorption and the thickness of the adsorbed layer were estimated. The results indicate that the PEGylated lipids are adsorbed as flat layers of around 1-3nm, and that DSPE-PEG5000 forms a thicker layer compared with DSPE-PEG2000. In addition, the mass adsorption to the drug crystals and the model surface are seemingly comparable. Furthermore, both DSPE-PEG2000 and DSPE-PEG5000 rendered stable drug nanocrystals, with a somewhat higher surface binding and stability seen for DSPE-PEG2000. These results suggest DSPE-PEG2000 and DSPE-PEG5000 as efficient nanocrystal stabilizers, with DSPE-PEG2000 giving a somewhat higher surface coverage and superior colloidal stability, whereas DSPE-PEG5000 shows a more extended structure that may have advantages for prolongation of circulation time in vivo and facilitation for targeting modifications.

Capillary saturation and desaturation

Capillary desaturation experiments produce disconnected (trapped) ganglia of mesoscopic sizes intermediate between pore size and system size. Experimental evidence for interactions between these mesoscale clusters during desaturation is analyzed and discussed within the established microscopic and macroscopic laws of Newton, Young-Laplace, and Darcy. A theoretical expression for capillary number correlations is introduced that seems to have remained unnoticed. It expresses capillary desaturation curves in terms of stationary capillary pressures and relative permeabilities. The theoretical expression shows that the plateau saturation in capillary desaturation curves may in general differ from the residual nonwetting saturation defined through the saturation limit of the main hysteresis loop. Hysteresis effects as well as the difference between wetting and nonwetting fluids are introduced into the analysis of capillary desaturation experiments. The article examines experiments with different desaturation protocols and discusses the existence of a mesoscopic length scale intermediate between pore scale and sample scale. The theoretical expression is derived entirely within the existing traditional theory of two-phase flow in porous media and compared to a recent experiment.

Flexible thin-film battery based on graphene-oxide embedded in solid polymer electrolyte

Enhanced safety of flexible batteries is an imperative objective due to the intimate interaction of such devices with human organs such as flexible batteries that are integrated with touch-screens or embedded in clothing or space suits. In this study, the fabrication and testing of a high performance thin-film Li-ion battery (LIB) is reported that is both flexible and relatively safer compared to the conventional electrolyte based batteries. The concept is facilitated by the use of solid polymer nanocomposite electrolyte, specifically, composed of polyethylene oxide (PEO) matrix and 1 wt% graphene oxide (GO) nanosheets. The flexible LIB exhibits a high maximum operating voltage of 4.9 V, high capacity of 0.13 mA h cm(-2) and an energy density of 4.8 mW h cm(-3). The battery is encapsulated using a simple lamination method that is economical and scalable. The laminated battery shows robust mechanical flexibility over 6000 bending cycles and excellent electrochemical performance in both flat and bent configurations. Finite element analysis (FEA) of the LIB provides critical insights into the evolution of mechanical stresses during lamination and bending.

A new model for the estimation of time of death from vitreous potassium levels corrected for age and temperature

Analysis of potassium concentration in the vitreous fluid of the eye is frequently used by forensic pathologists to estimate the postmortem interval (PMI), particularly when other methods commonly used in the early phase of an investigation can no longer be applied. The postmortem rise in vitreous potassium has been recognized for several decades and is readily explained by a diffusion of potassium from surrounding cells into the vitreous fluid. However, there is no consensus regarding the mathematical equation that best describes this increase. The existing models assume a linear increase, but different slopes and starting points have been proposed. In this study, vitreous potassium levels, and a number of factors that may influence these levels, were examined in 462 cases with known postmortem intervals that ranged from 2h to 17 days. We found that the postmortem rise in potassium followed a non-linear curve and that decedent age and ambient temperature influenced the variability by 16% and 5%, respectively. A long duration of agony and a high alcohol level at the time of death contributed less than 1% variability, and evaluation of additional possible factors revealed no detectable impact on the rise of vitreous potassium. Two equations were subsequently generated, one that represents the best fit of the potassium concentrations alone, and a second that represents potassium concentrations with correction for decedent age and/or ambient temperature. The former was associated with narrow confidence intervals in the early postmortem phase, but the intervals gradually increased with longer PMIs. For the latter equation, the confidence intervals were reduced at all PMIs. Therefore, the model that best describes the observed postmortem rise in vitreous potassium levels includes potassium concentration, decedent age, and ambient temperature. Furthermore, the precision of these equations, particularly for long PMIs, is expected to gradually improve by adjusting the constants as more reference data are added over time. A web application that facilitates this calculation process and allows for such future modifications has been developed.

Behavioural strategy of large perch Perca fluviatilis varies between a mesotrophic and a hypereutrophic lake

Behaviour of large perch Perca fluviatilis was studied in two lakes differing in environmental state i.e. mesotrophic v. hypereutrophic. A total of 20 adult perch P. fluviatilis (29-42 cm total length) in each lake were tagged with radio-transmitters, tracked and located eight times a day during six 24 h tracking periods over a year, enabling detection of differences in diel activity patterns and habitat use during summer and winter under two different environmental regimes. During summer, P. fluviatilis in the mesotrophic lake showed a distinct crepuscular activity pattern and a change from pelagic residency during daytime towards the littoral zone at night. In contrast, P. fluviatilis in the hypereutrophic lake were active during the entire diel cycle and were spread throughout the lake also during dark. During winter, crepuscular patterns of activity were seen in both lakes. Condition factor of large P. fluviatilis did not differ between the two lakes. Thus, it is suggested that P. fluviatilis in the hypereutrophic turbid lake adopted an alternative behaviour for successful foraging, being uniformly active throughout the diel cycle.

Effect of boat noise and angling on lake fish behaviour

The effects of disturbances from recreational activities on the swimming speed and habitat use of roach Rutilus rutilus, perch Perca fluviatilis and pike Esox lucius were explored. Disturbances were applied for 4 h as (1) boating in short intervals with a small outboard internal combustion engine or (2) boating in short intervals combined with angling with artificial lures between engine runs. The response of the fish species was evaluated by high-resolution tracking using an automatic acoustic telemetry system and transmitters with sub-minute burst rates. Rutilus rutilus swimming speed was significantly higher during disturbances [both (1) and (2)] with an immediate reaction shortly after the engine started. Perca fluviatilis displayed increased swimming activity during the first hour of disturbance but not during the following hours. Swimming activity of E. lucius was not significantly different between disturbance periods and the same periods on days without disturbance (control). Rutilus rutilus increased their use of the central part of the lake during disturbances, whereas no habitat change was observed in P. fluviatilis and E. lucius. No difference in fish response was detected between the two types of disturbances (boating with and without angling), indicating that boating was the primary source of disturbance. This study highlights species-specific responses to recreational boating and may have implications for management of human recreational activities in lakes.

Pore-scale micro-computed-tomography imaging: nonwetting-phase cluster-size distribution during drainage and imbibition

We investigated the cluster-size distribution of the residual nonwetting phase in a sintered glass-bead porous medium at two-phase flow conditions, by means of micro-computed-tomography (μCT) imaging with pore-scale resolution. Cluster-size distribution functions and cluster volumes were obtained by image analysis for a range of injected pore volumes under both imbibition and drainage conditions; the field of view was larger than the porosity-based representative elementary volume (REV). We did not attempt to make a definition for a two-phase REV but used the nonwetting-phase cluster-size distribution as an indicator. Most of the nonwetting-phase total volume was found to be contained in clusters that were one to two orders of magnitude larger than the porosity-based REV. The largest observed clusters in fact ranged in volume from 65% to 99% of the entire nonwetting phase in the field of view. As a consequence, the largest clusters observed were statistically not represented and were found to be smaller than the estimated maximum cluster length. The results indicate that the two-phase REV is larger than the field of view attainable by μCT scanning, at a resolution which allows for the accurate determination of cluster connectivity.

Possible transmission of Candida albicans on an intensive care unit: genotype and temporal cluster analyses

BACKGROUND

Nosocomial transmission of Candida spp. has not been fully explored and previous studies have shown conflicting results.

AIM

To evaluate the possible nosocomial transmission of Candida spp. on an intensive care unit (ICU).

METHODS

A prospective study was conducted for a period of 19 months, including all patients on our ICU with growth of Candida spp. from surveillance and directed cultures. Molecular typing with repetitive sequence-based polymerase chain reaction was used to define genotype relationships between the Candida albicans and Candida glabrata isolates. Candida isolates obtained from blood cultures taken from patients in our county outside the ICU were used as a reference. Temporal cluster analysis was performed to evaluate genotype distribution over time.

FINDINGS

Seventy-seven patients with 78 ICU stays, representing 12% of all ICU stays, were found to harbour 180 isolates of Candida spp. Molecular typing revealed 27 C. albicans genotypes and 10 of C. glabrata. Possible clustering, indicated by overlapping stays of patients with indistinguishable candida genotypes, was observed on seven occasions with C. albicans and on two occasions with C. glabrata. Two C. albicans genotypes were found significantly more often in the ICU group compared with the reference group. Moreover, C. albicans genotypes isolated from more than one patient were significantly more often found in the ICU group. Temporal cluster analysis revealed a significantly increased number of pairs with indistinguishable genotypes at a 21-day interval, indicating clustering.

CONCLUSION

This study indicates possible transmission of C. albicans between ICU patients based on genotyping and temporal cluster analysis.