Mechanistic Framework to Predict Maternal-Placental-Fetal Pharmacokinetics of Nifedipine Employing Physiologically Based Pharmacokinetic Modeling Approach

Nifedipine is used for treating mild to severe hypertension and preventing preterm labor in pregnant women. Nevertheless, concerns about nifedipine fetal exposure and safety are always raised. The aim of this study was to develop and validate a maternal-placental-fetal nifedipine physiologically based pharmacokinetic (PBPK) model and apply the model to predict maternal, placental, and fetal exposure to nifedipine at different pregnancy stages. A nifedipine PBPK model was verified with nonpregnant data and extended to the pregnant population after the inclusion of the fetoplacental multicompartment model that accounts for the placental tissue and different fetal organs within the Simcyp Simulator version 22. Model parametrization involved scaling nifedipine transplacental clearance based on Caco-2 permeability, and fetal hepatic clearance was obtained from in vitro to in vivo extrapolation encompassing cytochrome P450 3A7 and 3A4 activities. Predicted concentration profiles were compared with in vivo observations and the transplacental transfer results were evaluated using 2-fold criteria. The PBPK model predicted a mean cord-to-maternal plasma ratio of 0.98 (range, 0.86-1.06) at term, which agrees with experimental observations of 0.78 (range, 0.59-0.93). Predicted nifedipine exposure was 1.4-, 2.0-, and 3.0-fold lower at 15, 27, and 39 weeks of gestation when compared with nonpregnant exposure, respectively. This innovative PBPK model can be applied to support maternal and fetal safety assessment for nifedipine at various stages of pregnancy.

Cannabinoid type 2 receptor inhibition enhances the antidepressant and proneurogenic effects of physical exercise after chronic stress

Chronic stress is a major risk factor for neuropsychiatric conditions such as depression. Adult hippocampal neurogenesis (AHN) has emerged as a promising target to counteract stress-related disorders given the ability of newborn neurons to facilitate endogenous plasticity. Recent data sheds light on the interaction between cannabinoids and neurotrophic factors underlying the regulation of AHN, with important effects on cognitive plasticity and emotional flexibility. Since physical exercise (PE) is known to enhance neurotrophic factor levels, we hypothesised that PE could engage with cannabinoids to influence AHN and that this would result in beneficial effects under stressful conditions. We therefore investigated the actions of modulating cannabinoid type 2 receptors (CB2R), which are devoid of psychotropic effects, in combination with PE in chronically stressed animals. We found that CB2R inhibition, but not CB2R activation, in combination with PE significantly ameliorated stress-evoked emotional changes and cognitive deficits. Importantly, this combined strategy critically shaped stress-induced changes in AHN dynamics, leading to a significant increase in the rates of cell proliferation and differentiation of newborn neurons, overall reduction in neuroinflammation, and increased hippocampal levels of BDNF. Together, these results show that CB2Rs are crucial regulators of the beneficial effects of PE in countering the effects of chronic stress. Our work emphasises the importance of understanding the mechanisms behind the actions of cannabinoids and PE and provides a framework for future therapeutic strategies to treat stress-related disorders that capitalise on lifestyle interventions complemented with endocannabinoid pharmacomodulation.

Dupilumab-associated ocular adverse events are predicted by low tear break-up time and correlate with high IL-33 tear concentrations in patients with atopic dermatitis

Dupilumab, blocking IL-4 and IL-13 signals, improves atopic dermatitis and Quality of Life but might be also associated with the occurrence of ocular adverse events (OAEs). The main objective of our prospective study was to characterize the cytokine and chemokine profile in the tear fluid of dupilumab-treated patients with moderate-to- severe atopic dermatitis and to identify biomarkers predicting the occurrence of ocular adverse events. Patients with moderate-to-severe AD underwent dermatological and ophthalmological evaluation at the baseline (T0) and week 16 or at the time of an eventual ocular adverse events (T1). A multiplex immunoassay measuring multiple cytokines and chemokines in the tear fluid extracted during ocular examination at both T0 and T1 was performed. Thirty-nine patients with moderate-to-severe AD and treated with dupilumab were included in the study. Baseline tear fluid levels revealed a significantly higher concentration of type 2 cytokines and chemokines in AD patients than healthy controls. The occurrence of ocular adverse events during dupilumab therapy was associated with a significant increase of IL-33 tear fluid levels and a significantly lower tear break-up time, this latter also identified as predictive factor. Our findings suggest that the ophthalmological examination should be considered a valid support to identify patients at risk of developing OAEs and to provide their appropriate management.

Failure to predict amikacin elimination in critically ill patients with cancer based on the estimated glomerular filtration rate: applying PBPK approach in a therapeutic drug monitoring study

PURPOSE

The aim of this work was to integrate the Therapeutic Drug Monitoring (TDM) with the model-informed precision dosing (MIPD) approach, using Physiologically-based Pharmacokinetic/Pharmacodynamic (PBPK/PD) modelling and simulation, to explore the relationship between amikacin exposure and estimated glomerular filtration rate (GFR) in critically ill patients with cancer.

METHODS

In the TDM study, samples from 51 critically-ill patients with cancer treated with amikacin were analysed. Patients were stratified according to renal function based on GFR status. A full-body PBPK model with 12 organs model was developed using Simcyp V. 21, including steady-state volume of distribution of 0.21 L/kg and renal clearance of 6.9 L/h in healthy adults. PK parameters evaluated were within the 2-fold error range.

RESULTS

During the validation step, predicted vs observed amikacin clearance values after single infusion dose in patients with normal renal function, mild and moderate renal impairment were 7.6 vs 8.1 L/h (7.5 mg/kg dose); 3.8 vs 4.5 L/h (1500 mg dose) and 2.2 vs 3.1 L/h (25 mg/kg dose), respectively. However, predicted vs observed amikacin clearance after a single dose infusion of 1400 mg in critically-ill patients with cancer were 1.46 vs 1.63 (P = 0.6406) L/h (severe), 2.83 vs 1.08 (P < 0.05) L/h (moderate), 4.23 vs 2.49 (P = 0.0625) L/h (mild) and 7.41 vs 3.36 (P < 0.05) L/h (normal renal function).

CONCLUSION

This study demonstrated that estimated GFR did not predict amikacin elimination in critically-ill patients with cancer. Further studies are necessary to find amikacin PK covariates to optimize the pharmacotherapy in this population. Therefore, TDM of amikacin is imperative in cancer patients.

Optimizing Therapeutic Drug Monitoring in Pregnant Women: A Critical Literature Review

BACKGROUND

More than 90% of pregnant women take at least one drug during pregnancy. Drug dose adjustments during pregnancy are sometimes necessary due to various pregnancy-induced physiological alterations frequently associated with lower plasma concentrations. However, the clinical relevance or benefits of therapeutic drug monitoring (TDM) in pregnant women have not been specifically studied. Clinical pharmacokinetic studies in pregnant women are incredibly challenging for many reasons. Despite this, regulatory agencies have made efforts to encourage the inclusion of this population in clinical trials to achieve more information on the pharmacotherapy of pregnant women. This review aims to provide support for TDM recommendations and dose adjustments in pregnant women.

METHODS

The search was conducted after a predetermined strategy on PubMed and Scopus databases using the MeSH term "pregnancy" alongside other terms such as "Pregnancy and dose adjustment," "Pregnancy and therapeutic drug monitoring," "Pregnancy and PBPK," "Pregnancy and pharmacokinetics," and "Pregnancy and physiological changes."

RESULTS

The main information on TDM in pregnant women is available for antiepileptics, antipsychotics, antidepressants, antibiotics, antimalarials, and oncologic and immunosuppressive drugs.

CONCLUSIONS

More data are needed to support informed benefit-risk decision making for the administration of drugs to pregnant women. TDM and/or pharmacokinetic studies could ensure that pregnant women receive an adequate dosage of an active drug. Mechanistic modeling approaches potentially could increase our knowledge about the pharmacotherapy of this special population, and they could be used to better design dosage regimens.

Pharmacometrics: The Already-Present Future of Precision Pharmacology

The use of mathematical modeling to represent, analyze, make predictions or providing information on data obtained in drug research and development has made pharmacometrics an area of great prominence and importance. The main purpose of pharmacometrics is to provide information relevant to the search for efficacy and safety improvements in pharmacotherapy. Regulatory agencies have adopted pharmacometrics analysis to justify their regulatory decisions, making those decisions more efficient. Demand for specialists trained in the field is therefore growing. In this review, we describe the meaning, history, and development of pharmacometrics, analyzing the challenges faced in the training of professionals. Examples of applications in current use, perspectives for the future, and the importance of pharmacometrics for the development and growth of precision pharmacology are also presented.

Quantitative imaging of magnetic nanoparticles in an unshielded environment using a large AC susceptibility array

Background

Non-invasive magnetic imaging techniques are necessary to assist magnetic nanoparticles in biomedical applications, mainly detecting their distribution inside the body. In Alternating Current Biosusceptometry (ACB), the magnetic nanoparticle's magnetization response under an oscillating magnetic field, which is applied through an excitation coil, is detected with a balanced detection coil system.

Results

We built a Multi-Channel ACB system (MC-ACB) containing nineteen pick-up coils and obtained 2D quantitative images of magnetic nanoparticle distributions by solving an inverse problem. We reconstructed the magnetic nanoparticles spatial distributions in a field of view of 14 × 14 cm² with a spatial resolution of 2.0 cm and sensitivity in the milligram scale. A correlation coefficient between quantitative reconstructed and nominal magnetic nanoparticle distributions above 0.6 was found for all measurements.

Conclusion

Besides other interesting features such as sufficient large field of view dimension for mice and rat studies, portability, and the ability to assess the quantitative magnetic nanoparticles distributions in real-time, the MC-ACB system is a promising tool for quantitative imaging of magnetic nanoparticles distributions in real-time, offering an affordable setup for easy access in clinical or laboratory environments.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

POS0151 PREGNANCIES IN PATIENTS WITH SPONDYLOARTHRITIS: DATA FROM 2 EUROPEAN CENTERS

Background

There is growing interest in reproductive issues in patients with Spondyloarthritis (SpA) and Psoriatic arthritis (PsA).

Objectives

To describe a real-life cohort of prospectively-followed pregnancies in SpA and PsA patients, focusing on obstetric outcome and on flare during pregnancies and post-partum.

Methods

Data on SpA and PsA pregnancies prospectively-followed in 2 European pregnancy clinics from 2010 to 2021 were retrospectively analysed.

Disease activity was assessed using ASDAS-CRP or DAS28-CRP according to the main involvement (peripheral or axial). Disease flare was defined as the need to treatment modification (introduction or increase ≥5mg/day of prednisone, introduction of cDMARD or bDMARD). Miscarriages were excluded from the analysis of flares.

Results

Data on 122 pregnancies (53 PsA and 69 ‘other SpA’: 39 axialSpA, 20 undifferentiated SpA, 6 IBD-related SpA, 4 reactive arthritis) in 102 patients (median age at conception: 34 [IQR: 31-36] years; median disease duration: 72 [24-132] months) were collected.

We recorded 98 (86%) live births and 16 (14%) miscarriages (8 missing data).

Cesarean section was performed in 15/98 (15%) cases. Median week of gestation at delivery was 39 [38-40]; 8 preterm births (<37 week of gestation) and 2 severe preterm births (<34 week of gestation) occurred. There was no difference between PsA or ‘other-SpA’ concerning pregnancy outcome and route of delivery.

Fourty-two pregnancies (40%) had at least 1 flare during pregnancy; 7 pregnancies had more than 1 flare. Overall, there were 13, 24 and 12 flares in the 1st, 2nd and 3rd trimester, respectively.

A higher frequency of patients with axial involvement was observed in the ‘flare’ group as compared to pregnancies without flare (83% vs 59%, p=0.02) (Table 1).

Table 1.

Comparison between ‘flare’ and ‘without flare’ groups.

FLARE (42)WITHOUT FLARE (64)pAge at conception (years)33 (31-37)33 (31-35)0.88Disease duration at conception (months)71 (24-120)60 (24-137)0.74PsA13 (31%)31 (48%)0.11‘Other SpA’29 (69%)33 (52%)0.11Axial involvement35 (83%)38 (59%)0.02Peripheral involvement30 (%)54 (%)0.17bDMARD useAny time before pregnancy16 (38%)19 (30%)0.49Stop at + pregnancy test/1st trimester8 (19%)4 (6%)0.09Start/continue 1st trimester7 (17%)10 (16%)0.89Start in 2ndtrimester5 (12%)00.02Start in 3rd trimester2 (5%)00.30Post-partum flare11/34 (32%)22/49 (45%)0.36

Continuous variables were compared using Mann-Whitney test; categorical variables were compared using Chi-square with Yates’ correction or Fisher’s exact test.

Medications resumed to treat flare were steroids (29 pregnancies), csDMARDs (14 pregnancies) and TNF-inhibitors (7 pregnancies: 5 during the 2nd and 2 during the 3rd trimester).

A post-partum flare was registered in 33/83 (40%) of cases, without difference between ‘flare’ group vs ‘without flare’ group (Table 1), as well as between PsA vs ‘other SpA’ pregnancies (47% vs 33%, p=0.2).

Conclusion

In this cohort of SpA pregnancies, 40% experienced a flare during pregnancy and 40% during post-partum. Flares occurred more frequently in the 2nd trimester and especially in patients with axial involvement, requiring the start of a TNF-inhibitor during the 2nd or the 3rd trimester in 7 pregnancies. Having a flare during pregnancy was not associated with a post-partum flare.

Disclosure of Interests

None declared

Validation of an analytical method based on QuEChERS and LC-MS/MS to quantify nine mycotoxins in plant-based milk

Plant-based beverages (popularly known as vegetable milk) have become increasingly important in recent years. However, the nonexistence of information on mycotoxin contamination is noticeable. We herein describe the development and validation of an analytical methodology that employs QuEChERS and LC-MS/MS for the simultaneous determination of nine mycotoxins (aflatoxins B1, B2, G1, and G2, fumonisins B1 and B2, ochratoxin A, zearalenone, and citreoviridin) in seven types of vegetable milk (peanut, oat, rice, cashew, maize, soybean, and coconut). The method provided the following quantification limits, recoveries at the lowest validated concentration and relative standard deviations under repeatability conditions at the lowest validated concentration, respectively: aflatoxin B1 (0.023 μg/l, 84.98 and 9.23%); aflatoxin B2 (0.024 μg/, 93.00 and 4.85%); aflatoxin G1 (0.057 μg/l, 98.85 and 5.53%); aflatoxin G2 (0.031 μg/l, 96.64 and 4.08%); fumonisin B1 (2.166 μg/l, 75.55 and 16.78%); fumonisin B2 (1.105 μg/l, 70.47 and 11.89%); ochratoxin A (0.104 μg/l, 72.05 and 5.12%); zearalenone (8.093 μg/l, 107.10 and 6.37%); citreoviridin (1.305 μg/l, 97.25 and 7.28%). The method uses small amounts of samples, solvents, and other inexpensive reagents with no need for laborious clean-up and pre-concentration steps. Its attractive characteristics (simplicity, low cost compared to procedures that use immunoaffinity columns, and full compatibility with routine analyses) make it potentially valuable. As a proof-of-principle, the validated methodology was applied to seven commercial samples of different compositions showing that some were contaminated with aflatoxins and ochratoxin A.

An easy and low-cost biomagnetic methodology to study regional gastrointestinal transit in rats

The identification of gastrointestinal (GI) motility disorders requires the evaluation of regional GI transit, and the development of alternative methodologies in animals has a significant impact on translational approaches. Therefore, the purpose of this study was to validate an easy and low-cost methodology (alternate current biosusceptometry - ACB) for the assessment of regional GI transit in rats through images. Rats were fed a test meal containing magnetic tracer and phenol red, and GI segments (stomach, proximal, medial and distal small intestine, and cecum) were collected to assess tracer's retention at distinct times after ingestion (0, 60, 120, 240, and 360 min). Images were obtained by scanning the segments, and phenol red concentration was determined by the sample's absorbance. The temporal retention profile, geometric center, gastric emptying, and cecum arrival were evaluated. The correlation coefficient between methods was 0.802, and the temporal retention of each segment was successfully assessed. GI parameters yielded comparable results between methods, and ACB images presented advantages as the possibility to visualize intrasegmental tracer distribution and the automated scan of the segments. The imaging approach provided a reliable assessment of several parameters simultaneously and may serve as an accurate and sensitive approach for regional GI research in rats.

Population pharmacokinetics and biodistribution of benznidazole in mice

OBJECTIVES

To evaluate the population pharmacokinetics of different benznidazole treatment regimens and the drug's biodistribution in mice.

METHODS

Two hundred mice were divided into five groups according to benznidazole dosing regimens: (1) 100 mg/kg/day for 20 days; (2) 100 mg/kg/day for 40 days; (3) 200 mg/kg/day for 20 days; (4) 40 mg/kg/day for 20 days; or (5) 40 mg/kg/day for 40 days. The mice were euthanized and blood, heart, liver, colon and brain were collected. Samples were prepared by liquid-liquid extraction and analysed by HPLC-diode-array detection. The pharmacokinetic analysis of benznidazole was evaluated via non-linear mixed-effects modelling using the NONMEN program.

RESULTS

Our results demonstrate that mouse weight allometrically influences benznidazole clearance; the AUC curve and the highest plasma concentration are dose proportional; benznidazole does not influence its own metabolism; its tissue distribution is limited; and the standard treatment regimen for Chagas' disease in mice (100 mg/kg/day for 20 days) is inadequate from a pharmacokinetic standpoint, as are the other regimens tested in this study (100 mg/kg/day for 40 days, 200 mg/kg/day for 20 days and 40 mg/kg/day for 20 or 40 days).

CONCLUSIONS

Benznidazole reformulations that allow better tissue penetration and plasma and tissue exposure should be evaluated to enable higher cure rates in both animals and patients. The population pharmacokinetic model developed here can allow optimization of the dosing regimen of benznidazole to treat experimental Chagas' disease. Determining appropriate treatment regimens in animals allows translation of these to clinical studies.

Chiral Transplacental Pharmacokinetics of Fexofenadine: Impact of P-Glycoprotein Inhibitor Fluoxetine Using the Human Placental Perfusion Model

PURPOSE

Fexofenadine is a well-identified in vivo probe substrate of P-glycoprotein (P-gp) and/or organic anion transporting polypeptide (OATP). This work aimed to investigate the transplacental pharmacokinetics of fexofenadine enantiomers with and without the selective P-gp inhibitor fluoxetine.

METHODS

The chiral transplacental pharmacokinetics of fexofenadine-fluoxetine interaction was determined using the ex vivo human placenta perfusion model (n = 4). In the Control period, racemic fexofenadine (75 ng of each enantiomer/ml) was added in the maternal circuit. In the Interaction period, racemic fluoxetine (50 ng of each enantiomer/mL) and racemic fexofenadine (75 ng of each enantiomer/mL) were added to the maternal circulation. In both periods, maternal and fetal perfusate samples were taken over 90 min.

RESULTS

The (S)-(-)- and (R)-(+)-fexofenadine fetal-to-maternal ratio values in Control and Interaction periods were similar (~0.18). The placental transfer rates were similar between (S)-(-)- and (R)-(+)-fexofenadine in both Control (0.0024 vs 0.0019 min^-1) and Interaction (0.0019 vs 0.0021 min^-1) periods. In both Control and Interaction periods, the enantiomeric fexofenadine ratios [R-(+)/S-(-)] were approximately 1.

CONCLUSIONS

Our study showed a low extent, slow rate of non-enantioselective placental transfer of fexofenadine enantiomers, indicating a limited fetal fexofenadine exposure mediated by placental P-gp and/or OATP2B1. The fluoxetine interaction did not affect the non-enantioselective transplacental transfer of fexofenadine. The ex vivo placental perfusion model accurately predicts in vivo placental transfer of fexofenadine enantiomers with remarkably similar values (~0.17), and thus estimates the limited fetal exposure.

Effect of red thyme oil (Thymus vulgaris L.) vapours on fungal decay, quality parameters and shelf-life of oranges during cold storage

This work has been aimed at studying the effect of red thyme oil (RTO, Thymus vulgaris L.) on the shelf-life and Penicillium decay of oranges during cold storage. RTO vapours significantly reduced (P ≤ 0.05) the percentage of infected wounds, the external growth area and the production of spores in inoculated orange fruit stored for 12 days at 7 °C in a polypropylene film selected for its appropriate permeability. Among the RTO compounds, p-cymene and thymol were the most abundant in packed boxes at the end of cold storage. The RTO vapours did not affect the main quality parameters of the oranges, or the taste and odour of the juice. The results have shown that an active packaging, using RTO vapours, could be employed, by the citrus industry, to extend the shelf-life of oranges for fresh market use and juice processing.

FRI0515 MATERNAL AND PERINATAL OUTCOMES IN WOMEN WITH RHEUMATIC DISEASES – A 10-YEAR EXPERIENCE FROM A PORTUGUESE TERTIARY CENTRE

Background:

Pregnant women with rheumatic diseases (RD) represent a population at a higher risk for adverse pregnancy outcomes (APO). At our unit, these patients (pts) are surveilled at a high-risk pregnancy clinic, by both rheumatologists and obstetricians.

Objectives:

To assess pregnancy outcomes in pts with RD surveilled at our unit over the last decade.

Methods:

Single-centre observational retrospective study of pregnant women with RD followed at a portuguese tertiary centre between 2009 to 2019.

Results:

Overall, 353 pregnancies (preg) in 295 pts with RD were managed at our unit. Table 1 summarizes clinical data and the main APO recorded. Systemic lupus erythematous (SLE) was the leading diagnosis followed by spondyloarthritis (SpA) and rheumatoid arthritis (RA). Antiphospholipid syndrome (APS) was diagnosed in 49 (13.9%) preg. We documented 284 (78%) live births (9 twin preg), 32 (10%) miscarriages, 7 (2%) elective abortions, 2 stillbirths (0.6%) and 2 ectopic preg; 35 (10%) of the overall preg were lost to follow up before delivery. Miscarriages occurred predominantly in pts with APS (34%). Fetal growth restriction (FGR) was recorded in 6% of preg, more than 1/3 of those in pts with APS. Preeclampsia (PE) complicated a total of 10 (4%) preg, 3 of those with superimposed HELLP syndrome, with SLE and APS accounting for 60% of the cases. Preterm births (15.5%) occurred mainly in APS, SLE and juvenile idiopathic arthritis (JIA) pts. Neonatal lupus ensued in 3 (3.8%) preg positive for anti-Ro/La antibodies. No neonatal deaths were recorded. SpA and RA represented the diseases which flared the most considering both pregnancy and the postpartum period.

Table 1.

Pregnancy outcomes by disease

Main diagnosisN, %Gest age at delivery(weeks)MiscarrFGRPEPreterm birthsFlares in pregFlares in PPSLE116,32.938±2.313/110,11.86/82,7.35/78,6.415/76,21.116/92,17.45/79,6.3SpA60,1739±2.62/55,3.65/44,11.41/45,2.25/40,12.518/40,455/23,21.7RA51,14.439±1.26/49,12.21/35,2.91/33,31/29,3.410/37,277/30,23.3Vasculitis25,7.138±1.81/24,4.21/21,4.80/19,04/21,197/23,30.42/17,11.8Primary APS22,6.238±1.63/22,13.61/17,5.91/16,6.32/16,12.5NANAJIA17,4.838±2.51/17,5.90/12,00/11,04/12,33.32/13,15.41/8,12.5UCTD15,4.239±1.52/15,13.30/11,01/10,101/11,9.10/15,00/15,0Primary Sjögren Syndrome12,3.439±1.40/11,00/9,00/10,01/9,11.11/8,12.50/6,0Others35,9.938±2.34/31,12.92/20,101/18,5.63/18,16.74/27,14.81/22,4.5Total353,10038±2.232/334,9.616/251,6.410/240,4.236/232,15.558/255,22.721/200,10.5Secondary diagnosisAPS2737±2.78/26,30.85/16,31.32/12,16.75/15,33.3NANASjögren Syndrome937±2.51/9,11.11/7,14.30/7,03/6,50NANA

Legend - gest: gestational; miscarr: miscarriages; NA – not applicable; PP: postpartum; preg: pregnancy; UCTD - Undifferentiated connective tissue disease. Continuous variables are presented as mean±SD. Categorical variables as n/mN, % - modified(m)N stands for total N – (not applicable+missing data); “Others” accounts for diagnosis with N≤6, such as APS non criteria, mixed connective tissue disease, myositis, overlap syndromes, Still’s disease and systemic sclerosis.

Conclusion:

In pregnant women with RD, it is of vital importance to be aware of the increased risk for APO. In our cohort, APS and SLE were the conditions most associated with APO, while SpA and RA were responsible for most maternal flares. Nevertheless, the majority of these pts, surveilled by a multidisciplinary team, had successful gestations.

Disclosure of Interests:

None declared

Growth and metabolite production of a grape sour rot yeast-bacterium consortium on different carbon sources

The present study was designed to evaluate possible sugar-based trophic interactions between acetic acid bacteria (AAB) and non-Saccharomyces yeasts (NSY) involved in table grape sour rot, a disease in which berries spoilage is caused by the accumulation of several microbial metabolites. Acetobacter syzygii LMG 21419 (As) and Candida zemplinina CBS 9494 (Cz), a simplified AAB-NSY association responsible for table grape sour rot, grew differently in a minimal medium (YP) supplemented with glucose, ethanol, acetic and gluconic acid under monoculture conditions. In As -Cz co-culture media, after 24 h of incubation, As showed high relative abundance in YP-ethanol, whereas Cz was the dominant strain in YP-glucose medium. Co-culture in YP-glucose showed that glucose was converted into ethanol by Cz that, in turn, promoted the growth of As population. Gluconic acid was the main bacterial metabolite from glucose in monoculture, whereas acetic acid putatively derived from ethanol oxidation was found only in co-culture. However, gluconic acid showed inhibitory effect against As whereas acetic acid mainly inhibited Cz. Negative effects of both metabolites were mitigated in the glucose-supplemented medium. The results suggest a possible metabolic- based temporal succession between AAB and NSY during grape sour rot development. At the begin of sour rot, low glucose concentration promotes NSY producing ethanol, then, the AAB could take advantage from the oxidation of ethanol into acetic acid, becoming the dominant microbial sour rot population during the late stages of the process.

Medication persistence and risk of fracture among female Medicare beneficiaries diagnosed with osteoporosis

We examined the relationship between persistent osteoporosis medication use and fracture risk among female Medicare beneficiaries diagnosed with osteoporosis using Medicare claims, 2009-2012. Persistent use was associated with reduced risk of fracture and significantly lower total health care costs in the follow-up period. Results were consistent using different analytical methods.

INTRODUCTION

This study aimed to examine the relationship between medication persistence and fracture risk among female Medicare beneficiaries diagnosed with osteoporosis.

METHODS

Elderly female Medicare beneficiaries diagnosed with osteoporosis and initiated on osteoporosis medication January 1, 2009-June 30, 2011, were included. Persistent medication use was defined as continuous use (no gap ≥ 60 days) for 1 year or longer. The key outcome was fragility fracture. A difference-in-difference analysis was performed at the log scale of fracture rate using a Poisson regression model with months 1-6 before medication initiation as the pre-initiation period and up to 18 months after as the post-initiation period. Total health care costs were compared using a similar approach. Sensitivity analyses were conducted using different pre- and post-initiation periods.

RESULTS

The study included 294,369 patients; 32.9% were persistent osteoporosis medication users and 67.1% non-persistent (< 12 months continuous use). Fracture incidence rates were 16.2 per 100 patient-years pre-initiation and 4.1 post-initiation for persistent users; corresponding rates for non-persistent users were 19.0 and 7.3 per 100 patient-years. The adjusted post-/pre-initiation fracture rate ratios were 0.284 for persistent and 0.411 for non-persistent users. The ratio of the two rate ratios was 0.692 (persistent vs. non-persistent, p < 0.0001), suggesting a significantly greater fracture rate reduction for persistent users. Adjusted cost ratios were significantly lower for persistent users. Sensitivity analyses results were similar.

CONCLUSIONS

Persistent use of osteoporosis medications was associated with reduced risk of fracture and significantly lower total health care costs. Payers and patients would benefit from interventions aimed at improving medication persistence.

Rudiment resorption as a response to starvation during larval development in the sea urchin Strongylocentrotus droebachiensis

Phenotypic flexibility (reversible phenotypic change) enables organisms to couple internal, ontogenetic responses with external, environmental cues. Phenotypic flexibility also provides organisms with the capacity to buffer stereotypical internal, developmental processes from unpredictable external, ecological events. Echinoids exhibit dramatic phenotypic flexibility in response to variation in exogenous nutrient supplies. The extent to which echinoids display this flexibility has been explored incompletely and research hitherto has been conducted predominantly on larval structures and morphologies. We investigated experimentally the extent to which the primordial juvenile, the developing rudiment, can exhibit the first phase in phenotypic flexibility among individuals. We report for the first time on rudiment regression and complete resorption as a response to starvation during larval development in the sea urchin Strongylocentrotus droebachiensis (O.F. Müller, 1776) and identify a developmental “window of opportunity” within which this can occur. Based on our observations and previous suggestions, we speculate that sea urchin rudiments might provide means of buffering development during unfavorable conditions.

Reducing marine eutrophication may require a paradigmatic change

Marine eutrophication in the North-East Atlantic (NEA) strongly relies on nutrient enrichment at the river outlets, which is linked to human activities and land use in the watersheds. The question is whether human society can reduce its nutrient emissions by changing land use without compromising food security. A new version of Riverstrahler model (pyNuts-Riverstrahler) was designed to estimate the point and diffuse nutrient emissions (N, P, Si) to the rivers depending on land use in the watersheds across a large domain (Western Europe agro-food systems, waste water treatment). The loads from the river model have been used as inputs to three marine ecological models (PCOMS, ECO-MARS3D, MIRO&CO) covering together a large part of the NEA from the Iberian shelf to the Southern North Sea. The modelling of the land-ocean continuum allowed quantifying the impact of changes in land use on marine eutrophication. Pristine conditions were tested to scale the current eutrophication with respect to a "natural background" (sensu WFD), i.e. forested watersheds without any anthropogenic impact. Three scenarios representing potential management options were also tested to propose future perspectives in mitigating eutrophication. This study shows that a significant decrease in nitrogen fluxes from land to sea is possible by adapting human activities in the watersheds, preventing part of the eutrophication symptoms in the NEA rivers and adjacent coastal zones. It is also shown that any significant achievement in that direction would very likely require paradigmatic changes at social, economic and agricultural levels. This requires reshaping the connections between crop production and livestock farming, and between agriculture and local human food consumption. It also involves cultural changes such as less waste production and a shift towards lower-impact and healthier diets where half of the animal products consumption is replaced by vegetal proteins consumption, known as a demitarian diet (http://www.nine-esf.org/node/281/index.html).

Estimating the long-term functional burden of osteoporosis-related fractures

Although fractures are associated with short-term reductions in functional status, there is limited information on longer-term burden of fracture. This study documents evidence of an association between fractures and significant declines and functional health and activities that persist but attenuate beyond two years.

INTRODUCTION

Although fractures are associated with short-term reductions in functional status and may have other short-term effects on healthcare utilization (hospitalization and follow-up care), there is limited information on long-term burden of fracture beyond 12 to 24 months post-fracture. Analysis of the long-term health burden can inform policymakers, health care practitioners, and payers.

METHODS

We acquired a data set containing the 1992-2012 Health and Retirement Survey data linked to the same individuals' Medicare claims. Fracture cases (n = 745) were matched to non-fracture controls using propensity scores matching. A regression-adjusted difference-in-difference (DD) approach was used to compare the change in functional status measures from baseline to two post-fracture periods for fracture cases relative to the change over the same time periods for matched controls. Self-reported measures of functional status were examined: limitations to activities of daily living (ADLs), limitations to instrumental activities of daily living (IADLs), a mobility index, a gross motor skills index, a fine motor skills index, and self-reported general health status.

RESULTS

Fracture cases reported increases in limitations to ADLs, difficulties with mobility, difficulties with gross motor skills, and difficulties with fine motor skills in each HRS collection period (the survey is administered every 2 years) following the fracture or index date (thus up to two years later) than matched controls (all p values < 0.05). The magnitude of these effects diminished in the second post-fracture wave (two to four years after fracture/index date), but they were still statistically significant.

CONCLUSIONS

Results suggest that fractures are associated with significant declines in some measures of functional activities up to two years following the fracture. The effects persist beyond two years but are smaller in magnitude.

Tau-dependent suppression of adult neurogenesis in the stressed hippocampus

Stress, a well-known sculptor of brain plasticity, is shown to suppress hippocampal neurogenesis in the adult brain; yet, the underlying cellular mechanisms are poorly investigated. Previous studies have shown that chronic stress triggers hyperphosphorylation and accumulation of the cytoskeletal protein Tau, a process that may impair the cytoskeleton-regulating role(s) of this protein with impact on neuronal function. Here, we analyzed the role of Tau on stress-driven suppression of neurogenesis in the adult dentate gyrus (DG) using animals lacking Tau (Tau-knockout; Tau-KO) and wild-type (WT) littermates. Unlike WTs, Tau-KO animals exposed to chronic stress did not exhibit reduction in DG proliferating cells, neuroblasts and newborn neurons; however, newborn astrocytes were similarly decreased in both Tau-KO and WT mice. In addition, chronic stress reduced phosphoinositide 3-kinase (PI3K)/mammalian target of rapamycin (mTOR)/glycogen synthase kinase-3β (GSK3β)/β-catenin signaling, known to regulate cell survival and proliferation, in the DG of WT, but not Tau-KO, animals. These data establish Tau as a critical regulator of the cellular cascades underlying stress deficits on hippocampal neurogenesis in the adult brain.

Adenosine A2A receptor regulation of microglia morphological remodeling-gender bias in physiology and in a model of chronic anxiety

Developmental risk factors, such as the exposure to stress or high levels of glucocorticoids (GCs), may contribute to the pathogenesis of anxiety disorders. The immunomodulatory role of GCs and the immunological fingerprint found in animals prenatally exposed to GCs point towards an interplay between the immune and the nervous systems in the etiology of these disorders. Microglia are immune cells of the brain, responsive to GCs and morphologically altered in stress-related disorders. These cells are regulated by adenosine A_2A receptors, which are also involved in the pathophysiology of anxiety. We now compare animal behavior and microglia morphology in males and females prenatally exposed to the GC dexamethasone. We report that prenatal exposure to dexamethasone is associated with a gender-specific remodeling of microglial cell processes in the prefrontal cortex: males show a hyper-ramification and increased length whereas females exhibit a decrease in the number and in the length of microglia processes. Microglial cells re-organization responded in a gender-specific manner to the chronic treatment with a selective adenosine A_2A receptor antagonist, which was able to ameliorate microglial processes alterations and anxiety behavior in males, but not in females.

The modulation of adult neuroplasticity is involved in the mood-improving actions of atypical antipsychotics in an animal model of depression

Depression is a prevalent psychiatric disorder with an increasing impact in global public health. However, a large proportion of patients treated with currently available antidepressant drugs fail to achieve remission. Recently, antipsychotic drugs have received approval for the treatment of antidepressant-resistant forms of major depression. The modulation of adult neuroplasticity, namely hippocampal neurogenesis and neuronal remodeling, has been considered to have a key role in the therapeutic effects of antidepressants. However, the impact of antipsychotic drugs on these neuroplastic mechanisms remains largely unexplored. In this study, an unpredictable chronic mild stress protocol was used to induce a depressive-like phenotype in rats. In the last 3 weeks of stress exposure, animals were treated with two different antipsychotics: haloperidol (a classical antipsychotic) and clozapine (an atypical antipsychotic). We demonstrated that clozapine improved both measures of depressive-like behavior (behavior despair and anhedonia), whereas haloperidol aggravated learned helplessness in the forced-swimming test and behavior flexibility in a cognitive task. Importantly, an upregulation of adult neurogenesis and neuronal survival was observed in animals treated with clozapine, whereas haloperidol promoted a downregulation of these processes. Furthermore, clozapine was able to re-establish the stress-induced impairments in neuronal structure and gene expression in the hippocampus and prefrontal cortex. These results demonstrate the modulation of adult neuroplasticity by antipsychotics in an animal model of depression, revealing that the atypical antipsychotic drug clozapine reverts the behavioral effects of chronic stress by improving adult neurogenesis, cell survival and neuronal reorganization.

Efficacy of gaseous ozone to counteract postharvest table grape sour rot

This work aims at studying the efficacy of low doses of gaseous ozone in postharvest control of the table grape sour rot, a disease generally attributed to a consortium of non-Saccharomyces yeasts (NSY) and acetic acid bacteria (AAB). Sour rot incidence of wounded berries, inoculated with 8 NSYstrains, or 7 AAB, or 56 yeast-bacterium associations, was monitored at 25 °C up to six days. Sour rot incidence in wounded berries inoculated with yeast-bacterium associations resulted higher than in berries inoculated with one single NSY or AAB strain. Among all NSY-AAB associations, the yeast-bacterium association composed of Candida zemplinina CBS 9494 (Cz) and Acetobacter syzygii LMG 21419 (As) showed the highest prevalence of sour rot; thus, after preliminary in vitro assays, this simplified As-Cz microbial consortium was inoculated in wounded berries that were stored at 4 °C for ten days under ozone (2.14 mg m^-3) or in air. At the end of cold storage, no berries showed sour-rot symptoms although ozonation mainly affected As viable cell count. After additional 12 days at 25 °C, the sour rot index of inoculated As-Cz berries previously cold-stored under ozone or in air accounted for 22.6 ± 3.7% and 66.7 ± 4.5%, respectively. Molecular analyses of dominant AAB and NSY populations of both sound and rotten berries during post-refrigeration period revealed the appearance of new strains mainly belonging to Gluconobacter albidus and Hanseniaspora uvarum species, respectively. Cold ozonation resulted an effective approach to extend the shelf-life of table grapes also after cold storage.

Adult hippocampal neuroplasticity triggers susceptibility to recurrent depression

Depression is a highly prevalent and recurrent neuropsychiatric disorder associated with alterations in emotional and cognitive domains. Neuroplastic phenomena are increasingly considered central to the etiopathogenesis of and recovery from depression. Nevertheless, a high number of remitted patients experience recurrent episodes of depression, remaining unclear how previous episodes impact on behavior and neuroplasticity and/or whether modulation of neuroplasticity is important to prevent recurrent depression. Through re-exposure to an unpredictable chronic mild stress protocol in rats, we observed the re-appearance of emotional and cognitive deficits. Furthermore, treatment with the antidepressants fluoxetine and imipramine was effective to promote sustained reversion of a depressive-like phenotype; however, their differential impact on adult hippocampal neuroplasticity triggered a distinct response to stress re-exposure: while imipramine re-established hippocampal neurogenesis and neuronal dendritic arborization contributing to resilience to recurrent depressive-like behavior, stress re-exposure in fluoxetine-treated animals resulted in an overproduction of adult-born neurons along with neuronal atrophy of granule neurons, accounting for an increased susceptibility to recurrent behavioral changes typical of depression. Strikingly, cell proliferation arrest compromised the behavior resilience induced by imipramine and buffered the susceptibility to recurrent behavioral changes promoted by fluoxetine. This study shows that previous exposure to a depressive-like episode impacts on the behavioral and neuroanatomical changes triggered by subsequent re-exposure to similar experimental conditions and reveals that the proper control of adult hippocampal neuroplasticity triggered by antidepressants is essential to counteract recurrent depressive-like episodes.

Linking canonical microcircuits and neuronal activity: Dynamic causal modelling of laminar recordings

Neural models describe brain activity at different scales, ranging from single cells to whole brain networks. Here, we attempt to reconcile models operating at the microscopic (compartmental) and mesoscopic (neural mass) scales to analyse data from microelectrode recordings of intralaminar neural activity. Although these two classes of models operate at different scales, it is relatively straightforward to create neural mass models of ensemble activity that are equipped with priors obtained after fitting data generated by detailed microscopic models. This provides generative (forward) models of measured neuronal responses that retain construct validity in relation to compartmental models. We illustrate our approach using cross spectral responses obtained from V1 during a visual perception paradigm that involved optogenetic manipulation of the basal forebrain. We find that the resulting neural mass model can distinguish between activity in distinct cortical layers - both with and without optogenetic activation - and that cholinergic input appears to enhance (disinhibit) superficial layer activity relative to deep layers. This is particularly interesting from the perspective of predictive coding, where neuromodulators are thought to boost prediction errors that ascend the cortical hierarchy.

Modeling the transport pathways of harmful algal blooms in the Iberian coast

The prediction of the path of harmful algal blooms (HABs) along the coast can be achieved using numerical models of ocean circulation in order to reproduce the hydrodynamics of the study area. With this setting, our work aimed at the (1) study of key past events to evaluate the model ability to reproduce the transport pathways of blooms along the Iberian coast, and (2) to assess the relevance of such strictly physical approach. The simulations described here rely on the advection of lagrangian elements after a point release in a hypothetical location for bloom initiation, and the subsequent assessment of the influence of the surface currents transport on the extent of the bloom. Five events were simulated, accounting for blooms of Gymnodinium catenatum, Dinophysis acuminata and Pseudo-nitzschia spp. Model results were compared with field data from the National HAB monitoring program, and were used to evaluate some hypothesis in their interpretation. The effort compiled in this paper, though focused on the transport and dispersion of HAB (after bloom detection), was a critical step toward an integrative forecasting system to determine potential HAB impacted areas, also addressed in this Special Issue.

A HAB warning system for shellfish harvesting in Portugal

The development of sustainable shellfish aquaculture is highly dependent on the provision of reliable monitoring and predictive information on the occurrence of harmful algal blooms (HABs). The Portuguese HAB early warning system and shellfish closures presented here is a prototype, developed in the ASIMUTH project. It relies on weekly monitoring data composed of observations of HAB species and toxin concentrations within shellfish, and ocean circulation forecasts generated by an operational oceanographic model. The shellfish harvesting areas comprise coastal areas, estuaries+rías and coastal lagoons. The weekly bulletin characterizes the current shellfish closure situation and next week's forecasts for potentially impacted areas. The period analyzed ranged from 27 July 2013 to 17 March 2014, and describes the first skill assessment of the warning system. The forecast accuracy was evaluated, considering the number of forecasts that were verified to be correct the following week (85%) as well as the number of events not forecasted (false negatives, 12%) and those expected but did not occur (false positives, 3%). Variations were most visible in the first weeks of bulletin implementation and during autumn-winter months. The complementary use of field data, remote sensing and operational models led to more accurate predictions of blooms and range of the event.

Evaluation of Cognitive Functions through the Systemic Lisbon Battery: Normative Data

INTRODUCTION

This article is part of the Focus Theme of Methods of Information in Medicine on "Methodologies, Models and Algorithms for Patients Rehabilitation".

BACKGROUND

ICT is an emerging alternative to paper-and-pencil tests for the assessment of cognitive functions, allowing for the monitoring of participants' behavior while they perform simulations of instrumental activities of daily life (IADLs) in a virtual reality (VR) scenario. This requires normative values for each VR task, so that deviations to normality can be identified as indicators of cognitive impairment.

OBJECTIVES

To identify normative data for several IADL tasks that are available on the Systemic Lisbon Battery (SLB).

METHODS

Fifty-nine participants performed a series of VR tasks that require the use of the memory and executive function dimensions of cognitive functionality.

RESULTS

Normative data for the different subsets and total score of the SLB, based on proportion of correct hits per execution time, were identified. Age and experience with video games affect (respectively, negatively and positively) performance on the SLB and should be taken into account in assessment; on the other hand, gender and education do not.

CONCLUSIONS

Overall results suggest that the SLB may be useful to assess cognitive functioning during the execution of activities of daily living, but larger studies and with clinical samples are needed.