BENCHOP–SLV: the BENCHmarking project in Option Pricing–Stochastic and Local Volatility problems

In the recent project BENCHOP–the BENCHmarking project in Option Pricing we found that Stochastic and Local Volatility problems were particularly challenging. Here we continue the effort by introducing a set of benchmark problems for this type of problems. Eight different methods targeted for the Stochastic Differential Equation (SDE) formulation and the Partial Differential Equation (PDE) formulation of the problem, as well as Fourier methods making use of the characteristic function, were implemented to solve these problems. Comparisons are made with respect to time to reach a certain error level in the computed solution for the different methods. The implemented Fourier method was superior to all others for the two problems where it was implemented. Generally, methods targeting the PDE formulation of the problem outperformed the methods for the SDE formulation. Among the methods for the PDE formulation the ADI method stood out as the best performing one

Impact of a nutritional supplement (Impryl) on male fertility: study protocol of a multicentre, randomised, double-blind, placebo-controlled clinical trial (SUppleMent Male fERtility, SUMMER trial)

INTRODUCTION: Infertility is a worldwide problem and about 10%-15% of all couples will be affected by the inability to have children. In approximately 50% of infertile couples, a male factor is involved. Most of the male infertile cases are characterised as 'idiopathic', except for a small percentage of cases which are causative by a genetic aetiology. In the past decade, the role of oxidative stress related to sperm quality has been researched thoroughly and estimated to be the problem in 25%-87% of male infertility cases. Impryl is a nutritional supplement which works on the metabolic system and the regulation of oxidative stress by activating the 1-carbon cycle and therefore recycling of homocysteine. We hypothesise that the nutritional supplement Impryl in men of infertile couples might improve the ongoing pregnancy rate. METHODS AND ANALYSIS: We designed a multicentre, randomised, double-blind, placebo-controlled clinical trial. We aimed to include 1200 male adults aged 18-50 years, part of a couple that is diagnosed with infertility. The couple will either start or has already been started with fertility treatment, that is, expectative management (duration of 6 months), intrauterine insemination (IUI) with or without mild ovarian stimulation or ovulation induction, either in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI) treatment. Male participants will be randomised in either the Impryl or the placebo group, with identical appearance of the tablets to be distributed (doses: one tablet each day), for a total duration of maximal 6 months. Patients can start directly with fertility treatment and/or natural conception. The primary outcome is the number of ongoing pregnancies confirmed by ultrasound at ≥10 to 12 weeks, and conceived in the time window between randomisation up to and including month 6 of intervention use. Secondary outcomes are change in semen parameters between baseline and after 3 months of intervention in the IUI/IVF/ICSI group, based on (prewash) total motile sperm count. Furthermore the number of pregnancies conceived in the optimal intervention time window (after full spermatogenesis of 72 days), overall number of pregnancies, time to pregnancy, embryo fertilisation rate in IVF/ICSI, embryo-utilisation rate in IVF/ICSI, number of miscarriages, live birth rate and adverse events are documented within the study period of 15 months. ETHICS AND DISSEMINATION: The protocol is approved by the local medical ethical review committee at the Radboud University Medical Centre and by the national Central Committee on Research Involving Human Subjects. Findings will be shared with the academic and medical community, funding and patient organisations in order to contribute to optimisation of medical care and quality of life for patients with infertility. TRIAL REGISTRATION NUMBERS: NCT03337360 and NTR6551

A Network Meta-Analysis of Clinical Management Strategies for Treatment-Resistant Hypertension: Making Optimal Use of the Evidence

BACKGROUND: With the addition of surgical interventions to current medicinal treatments, it is increasingly challenging for clinicians to rationally choose among the various options for treating patients with apparent treatment-resistant hypertension (ATRHTN). This study aims to establish the comparative effectiveness of mineralocorticoid receptor antagonists (MRA), renal denervation (RDN), darusentan and central arteriovenous anastomosis (CAA) for patients with ATRHTN by performing a network meta-analysis. METHODS: Data Sources: Studies from recent meta-analyses for RDN and placebo effect were supplemented with a systematic search for MRAs in ATRHTN in the Pubmed, EMBASE, CINAHL and Cochrane databases through November 2016. STUDY SELECTION: Randomized controlled trials comparing treatment options for patients with ATRHTN. DATA EXTRACTION AND SYNTHESIS: Data were extracted using predefined data extraction forms, including the Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria. A Bayesian random effects model was used to conduct a network meta-analysis. Spironolactone was used as the main comparator. Main Outcomes and Measures: Reduction in 24-h ambulatory blood pressure measurement (ABPM). RESULTS: Twenty articles met our inclusion criteria, and seven treatment alternatives were compared. Compared to MRA, CAA had the highest probability of being more effective, further reducing 24-h SBP (-4.8 mmHg [-13.0, 3.7]) and 24-h DBP (-9.7 mmHg [-18, -0.63]). This difference is likely to be clinically meaningful, with a probability of 78 and 96% at a threshold of a 2-mmHg reduction in blood pressure. CONCLUSIONS: When compared to MRA as anchor, darusentan, CAA and RDN are not more effective in achieving a clinically significant reduction in ambulatory blood pressure in individuals with apparent treatment-resistant hypertension

Effect of maternal and treatment-related factors on the prevalence of birth defects after PESA-ICSI and TESE-ICSI: a retrospective cohort study.

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Correlating signs and symptoms with pubovisceral muscle avulsions on magnetic resonance imaging

Item does not contain fulltextOBJECTIVE: We sought to correlate signs and symptoms of pelvic organ prolapse (POP) with pubovisceral muscle avulsions on magnetic resonance imaging (MRI). STUDY DESIGN: In this retrospective cohort study of 189 women with recurrent POP or unexplained symptoms of pelvic floor dysfunction, we reviewed T2-weighted pelvic floor MRI and categorized defects as minor or major avulsion, or as no defect present. Outcomes were correlated to quality-of-life questionnaire scores and data on obstetric and surgical history, together with POP-Quantification (POP-Q) measurements. Multivariable ordinal logistic regression analysis with manual backward elimination was applied to calculate odds ratios (ORs). RESULTS: Major pubovisceral avulsions were diagnosed in 83 (44%) women, minor avulsions in 49 (26%) women, while no defects were seen in 57 (30%) women. Women with a history of episiotomy or anterior vaginal wall reconstructive surgery had a higher OR for more severe pubovisceral muscle avulsions (adjusted OR, 3.77 and 3.29, respectively), as did women with symptoms of POP (OR, 1.01, per unit increase) or higher stage POP of the central vaginal compartment based on POP-Q measurement "C" (OR, 1.18). Women with symptoms of obstructive defecation were more likely to have no defect of the pubovisceral muscle on MRI (OR, 0.97, per unit increase). CONCLUSION: The variables episiotomy, previous anterior vaginal wall reconstructive surgery, POP-Q measurement "C," and symptoms scored with the Urogenital Distress Inventory "genital prolapse" and Defecatory Distress Inventory "obstructive defecation" subscales are correlated with pubovisceral muscle avulsions on pelvic floor MRI

Impact of body mass index and fat distribution on sex steroid levels in endometrial carcinoma: a retrospective study

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