Complications of reversible cerebral vasoconstriction syndrome in relation to age

INTRODUCTION

Reversible cerebral vasoconstriction syndrome (RCVS) has a heterogenous clinical and radiological presentation. We investigated whether RCVS complications vary according to age.

PATIENTS AND METHODS

In a pooled French cohort of 345 patients with RCVS, we assessed (1) rates of clinical and radiological complications, and (2) the functional outcome at 3 months according to age as a continuous variable, and in young patients aged ≤ 49 years versus those aged ≥ 50 years. The Commission Nationale Informatique et Liberté and the local ethics committee approved this study (registration number: 202100733).

RESULTS

The risk for any focal deficit and for any brain lesion were independently associated with increasing age (OR 1.4, 95% CI 1.1-1.8; p = 0.014, and OR 1.6, 95% CI 1.2-2.1; p < 0.001, respectively). Subtypes of brain lesions independently associated with increasing age were subarachnoid haemorrhage (OR 1.7, 95% CI 1.3-2.3; p < 0.001) and intracerebral haemorrhage (OR 1.5, 95% CI 1.1-2.2; p = 0.023). Frequency of cervical artery dissections peaked at age 30-39, and young age was independently associated with cervical artery dissections (OR 13.6, 95% CI 2.4-76.6; p = 0.003). Age had no impact on the functional outcome, with a modified Rankin scale score of 0-1 in > 96% of patients.

CONCLUSION

Age seems to influence rates and types of complications of RCVS, with young age being associated with cervical artery dissections, and increasing age with haemorrhagic complications. If confirmed in larger prospective studies, recognition of age-specific patterns might help to guide clinical management and to identify complications in cases of RCVS and vice versa.

Long-term treatment with lasmiditan in patients with migraine: Results from the open-label extension of the CENTURION randomized trial

BACKGROUND

Following the CENTURION phase 3 randomized controlled trial's four-month double-blind phase, this 12-month open-label extension collected data for up to one year about dose optimization, patterns of use, migraine-related disability, and quality of life during lasmiditan treatment.

METHODS

Migraine patients ≥18 years completing the double-blind phase and treating ≥3 migraine attacks could continue into the 12-month open-label extension. The initial oral lasmiditan dose was 100 mg; the dose could subsequently be adjusted to 50 mg or 200 mg at the investigator's discretion.

RESULTS

477 patients entered and 321 (72.1%) completed the extension; 445 (93.3%) treated ≥1 attack with lasmiditan. Of 11,327 attacks, 8654 (76.4%) were lasmiditan-treated (84.9% of these involved moderate or severe pain). By study end, 17.8%, 58.7%, and 23.4% of patients were taking lasmiditan 50, 100, and 200 mg, respectively. Mean improvements were observed in disability and quality of life. The most common treatment-emergent adverse event was dizziness (35.7% of patients, 9.5% of attacks).

CONCLUSIONS

During this 12-month extension, lasmiditan was associated with a high rate of study completion, most attacks were treated with lasmiditan, and patients reported improvements in migraine-related disability and quality of life. No new safety findings were observed with longer exposure.Trial registration: ClinicalTrials.gov (NCT03670810); European Union Drug Regulating Authorities Clinical Trials Database (EUDRA CT: 2018-001661-17).

Impairment of central retinal artery hemodynamics in affected and fellow eyes in giant cell arteritis patients with unilateral vision loss

OBJECTIVES

Permanent visual impairment is a major complication of giant cell arteritis (GCA). We investigated the added value of color Doppler imaging (CDI) of the central retinal artery (CRA) in patients with suspected GCA for early risk evaluation before temporal artery biopsy (TAB) results become available.

METHODS

We conducted a non-interventional observational study of 30 consecutive patients hospitalized for suspected GCA, including a comprehensive analysis of clinical, laboratory, imaging, CDI and pathology data. GCA was diagnosed or excluded (GCA+, GCA-, respectively) according to American College of Rheumatology (ACR) criteria and TAB findings. Three patients not meeting ACR criteria were excluded secondarily. The GCA- group contained ten patients, and the GCA+ group contained 17 patients, including eight with unilateral, transient or permanent clinical visual impairment (CVI).

RESULTS

Mean blood flow velocity (mBFV) in the CRA was impaired in the affected eyes of GCA + CVI+ patients (1.9 ± 0.9 cm.s^-1, p < 0.001) relative to controls (4.1 ± 1.0 cm.s^-1), GCA- patients (3.6 ± 0.7 cm.s^-1) and GCA + CVI- patients (3.8 ± 0.8 cm.s^-1). The mBFVs of the CRA was similar for affected and fellow eyes (right or left). CRA mBFV measurements effectively differentiated between patients with and without CVI (ROC-curve analysis, AUC = 0.925 [95%CI: 0.700 to 0.996], p < 0.0001, 88% sensitivity, 89% specificity, and cutoff of ≤2.7 cm.s^-1 for affected eyes; 75% sensitivity, 100% specificity and cutoff of ≤2.2 cm.s^-1 for fellow eyes).

CONCLUSION

CDI facilities the early detection of visual ischemia risk in GCA+ patients, justifying urgent high-dose corticosteroid administration to save at least the fellow eye before pathology results become available.

A unique service: how an embedded psychology team can help patients and genetics clinicians within a clinical genetics service

The Genetics service at Guy's hospital has dedicated in-house psychology provision aimed at supporting patients embarking on genetic testing through to coping with the aftermath of genetic diagnoses. This provision offers assessment and intervention within a brief 6-session therapy model and provides a range of therapeutic approaches. Patient satisfaction with the service is high and referral rates have greatly increased over the recent years. The Psychology Team also provides indirect support for patients as well as support for the Genetics Team such as contributing to MDT and informal case discussions, as well as teaching and training clinicians about psychological concepts. There are many advantages to having an embedded psychology service both for patients and genetics clinicians, such as good opportunities for liaising around referrals and conducting joint clinical sessions, as well as being easily able to identify psychological training needs. The service plans to further develop by offering group interventions and training opportunities to doctoral psychology trainees. We conclude that clinical psychologists can play a highly integral and essential role in the provision of psychosocial support for clinical genetics teams and provide an overview of the first such integrated clinical psychology service within clinical genetics in the United Kingdom.

Hemiplegic Migraine Associated With PRRT2 Mutations: A Clinical and Genetic Study

BACKGROUND AND OBJECTIVE

PRRT2 variants have been reported in a few cases of patients with hemiplegic migraine. To clarify the role of PRRT2 in familial hemiplegic migraine, we studied this gene in a large cohort of affected probands.

METHODS

PRRT2 was analyzed in 860 probands with hemiplegic migraine and PRRT2 mutations were identified in 30 probands. Genotyping of relatives identified a total of 49 persons with mutations whose clinical manifestations were detailed.

RESULTS

PRRT2 mutations were found in 12 of 163 probands previously tested negative for CACNA1A, ATP1A2 and SCN1A mutations, and in 18 of 697 consecutive probands screened simultaneously on the four genes. In this second group, pathogenic variants were found in 105 subjects, mostly in ATP1A2 (42%), followed by CACNA1A (26%), PRRT2 (17%) and SCN1A (15%). The PRRT2 mutations included seven distinct variants, five of which already described in persons with paroxysmal kinesigenic dyskinesia, and two new variants. Eight probands had a deletion of the whole PRRT2 gene.Among the 49 PRRT2 mutated patients, 26 had pure hemiplegic migraine, 16 had hemiplegic migraine associated with another manifestation: epilepsy (8), learning disabilities (5), hypersomnia (4) or abnormal movement (3). Three patients had epilepsy without migraine, two had paroxysmal kinesigenic dyskinesia without migraine, and one was asymptomatic.

CONCLUSION

PRRT2 should be regarded as the fourth autosomal dominant gene for hemiplegic migraine, and screened in any affected patient, together with the three other main genes. Further studies are needed to understand how the same loss of function PRRT2 mutations can lead to a wide range of neurologic phenotypes including paroxysmal movement disorder, epilepsy, learning disabilities, sleep disorder and hemiplegic migraine.

Type of headache at onset and risk for complications in reversible cerebral vasoconstriction syndrome

BACKGROUND

In a recent Italian study, 30% of patients with reversible cerebral vasoconstriction syndrome (RCVS) presented without thunderclap headache (TCH), and tended to present more severe forms of RCVS than patients with TCH. We aimed to analyze the risk for complications of RCVS in patients with and without TCH at onset.

METHODS

In a pooled cohort of 345 French patients with RCVS, we compared patients with and without TCH at onset regarding rates of neurological complications, and the functional outcome at 3 months.

RESULTS

As compared to the 281 patients with TCH at onset, the 64 patients without TCH had a higher risk for any neurological complication (61% vs. 24%, OR 4.9, 95% CI 2.8-8.7, p < 0.001). The association was strongest for cervical artery dissections (28% vs. 5%, OR 8.1, 95% CI 3.7-17.6, p < 0.001), followed by posterior reversible encephalopathy syndrome (17% vs. 3%, OR 7.1, 95% CI 2.7-18.4, p < 0.001), seizures (9% vs. 2.5%, OR 4.1, 95% CI 1.3-12.5, p = 0.019), and subarachnoid hemorrhage (41% vs. 16%, OR 3.5, 95% CI 1.9-6.3, p < 0.001). In multivariable analysis, the risk for any neurological complication remained significantly elevated in the absence of TCH (OR 3.5, 95% CI 1.8-6.8, p < 0.001). The functional outcome was equal in both groups, with a modified Rankin scale score of 0-1 in ≥90% of patients.

CONCLUSIONS

Absence of TCH at onset might predict a higher risk of complications in RCVS. Our results warrant further multicentric studies to prove this finding.

Revised guidelines of the French Headache Society for the diagnosis and management of migraine in adults. Part 1: Diagnosis and assessment

The French Headache Society proposes updated French guidelines for the management of migraine. The first part of these recommendations is focused on the diagnosis and assessment of migraine. First, migraine needs to be precisely diagnosed according to the currently validated criteria of the International Classification of Headache Disorders, 3d version (ICHD-3). Migraine-related disability has to be assessed and we suggest to use the 6 questions of the headache impact test (HIT-6). Then, it is important to check for risk factors and comorbidities increasing the risk to develop chronic migraine, especially frequency of headaches, acute medication overuse and presence of depression. We suggest to use a migraine calendar and the Hospital Anxiety and Depression scale (HAD). It is also necessary to evaluate the efficacy and tolerability of current migraine treatments and we suggest to systematically use the self-administered Migraine Treatment Optimization Questionnaire (M-TOQ) for acute migraine treatment. Finally, a treatment strategy and a follow-up plan have to be proposed. Guidelines for pharmacological and non-pharmacological treatments are presented in the second and third part of the recommendations.

Revised guidelines of the French headache society for the diagnosis and management of migraine in adults. Part 3: Non-pharmacological treatment

The French Headache Society proposes updated French guidelines for the management of migraine. This article presents the third part of the guidelines, which is focused on the non-pharmacological treatment of migraine, including physical exercise, dietary supplements and plants, diets, neuromodulation therapies, acupuncture, behavioral interventions and mindfulness therapy, patent foramen ovale closure and surgical nerve decompression.

Revised guidelines of the French headache society for the diagnosis and management of migraine in adults. Part 2: Pharmacological treatment

The French Headache Society proposes updated French guidelines for the management of migraine. This article presents the second part of the guidelines, which is focused on the pharmacological treatment of migraine, including both the acute treatment of attacks and the prophylaxis of episodic migraine as well as chronic migraine with and without medication overuse. The specific situations that can be encountered in women with migraine are also discussed, including pregnancy, menstrual migraine, contraception and hormonal replacement therapy.

Preventing Post-Lumbar Puncture Headache

Post-lumbar puncture headache is the main adverse event from lumbar puncture and occurs in 3.5% to 33% of patients, causing functional and socio-professional disability. We searched the post-lumbar puncture headache literature and, based on this review and personal expertise, identified and addressed 19 frequently asked questions regarding post-lumbar puncture headache risk factors and prevention. Among the nonmodifiable factors, older age is associated with a lower incidence of post-lumbar puncture headache, while female sex, lower body mass index, and history of headache might be associated with increased risk. The use of atraumatic, noncutting needles is the most effective intervention for post-lumbar puncture headache prevention. These needles are not more difficult to use than cutting needles. Other commonly recommended measures (eg, fluid supplementation, caffeine) appear unhelpful, and some (eg, bed rest) may worsen post-lumbar puncture headache.

Occipital Nerve Stimulation for Refractory Chronic Cluster Headache: A Cost-Effectiveness Study

INTRODUCTION

Occipital nerve stimulation (ONS) is proposed to treat refractory chronic cluster headache (rCCH), but its cost-effectiveness has not been evaluated, limiting its diffusion and reimbursement.

MATERIALS AND METHODS

We performed a before-and-after economic study, from data collected prospectively in a nation-wide registry. We compared the cost-effectiveness of ONS associated with conventional treatment (intervention and postintervention period) to conventional treatment alone (preintervention period) in the same patients. The analysis was conducted on 76 rCCH patients from the French healthcare perspective at three months, then one year by extrapolation. Because of the impact of the disease on patient activity, indirect cost, such as sick leave and disability leave, was assessed second.

RESULTS

The average total cost for three months was €7602 higher for the ONS strategy compared to conventional strategy with a gain of 0.07 quality-adjusted life-years (QALY), the incremental cost-effectiveness ratio (ICER) was then €109,676/QALY gained. The average extrapolated total cost for one year was €1344 lower for the ONS strategy (p = 0.5444) with a gain of 0.28 QALY (p < 0.0001), the ICER was then €-4846/QALY gained. The scatter plot of the probabilistic bootstrapping had 80% of the replications in the bottom right-hand quadrant, indicating that the ONS strategy is dominant. The average indirect cost for three months was €377 lower for the ONS strategy (p = 0.1261).

DISCUSSION

This ONS cost-effectiveness study highlighted the limitations of a short-time horizon in an economic study that may lead the healthcare authorities to reject an innovative strategy, which is actually cost-effective. One-year extrapolation was the proposed solution to obtain results on which healthcare authorities can base their decisions.

CONCLUSION

Considering the burden of rCCH and the efficacy and safety of ONS, the demonstration that ONS is dominant should help its diffusion, validation, and reimbursement by health authorities in this severely disabled population.

Long-Term Efficacy of Occipital Nerve Stimulation for Medically Intractable Cluster Headache

BACKGROUND

Occipital nerve stimulation (ONS) has been proposed to treat refractory chronic cluster headache (rCCH) but its efficacy has only been showed in small short-term series.

OBJECTIVE

To evaluate ONS long-term efficacy in rCCH.

METHODS

We studied 105 patients with rCCH, treated by ONS within a multicenter ONS prospective registry. Efficacy was evaluated by frequency, intensity of pain attacks, quality of life (QoL) EuroQol 5 dimensions (EQ5D), functional (Headache Impact Test-6, Migraine Disability Assessment) and emotional (Hospital Anxiety Depression Scale [HAD]) impacts, and medication consumption.

RESULTS

At last follow-up (mean 43.8 mo), attack frequency was reduced >50% in 69% of the patients. Mean weekly attack frequency decreased from 22.5 at baseline to 9.9 (P < .001) after ONS. Preventive and abortive medications were significantly decreased. Functional impact, anxiety, and QoL significantly improved after ONS. In excellent responders (59% of the patients), attack frequency decreased by 80% and QoL (EQ5D visual analog scale) dramatically improved from 37.8/100 to 73.2/100. When comparing baseline and 1-yr and last follow-up outcomes, efficacy was sustained over time. In multivariable analysis, low preoperative HAD-depression score was correlated to a higher risk of ONS failure. During the follow-up, 67 patients experienced at least one complication, 29 requiring an additional surgery: infection (6%), lead migration (12%) or fracture (4.5%), hardware dysfunction (8.2%), and local pain (20%).

CONCLUSION

Our results showed that long-term efficacy of ONS in CCH was maintained over time. In responders, ONS induced a major reduction of functional and emotional headache-related impacts and a dramatic improvement of QoL. These results obtained in real-life conditions support its use and dissemination in rCCH patients.

Positive effects of lumbar puncture simulation training for medical students in clinical practice

BACKGROUND

Lumbar puncture (LP) is an invasive medical procedure that can be done by any doctor. Several simulation-based trainings have been built however the evaluations of the theoretical knowledge and the impact of the simulation-based training have never been performed in real life. The objective was to evaluate the impact of a LP training on the theoretical knowledge improvement and the performance of a LP in clinical practice.

METHODS

Before and after medical students' training, theoretical knowledge and confidence level were assessed. Over a 6 months period, the impact of simulation training was evaluated by the success rate of students' first LP carried out in hospitalized patients and compared to the results of a no-training control.

RESULTS

Students' theoretical knowledge and confidence level showed significant improvement after simulation training on 115 students (p < 0.0001). The evaluation in real life based on 41 students showed that the success rate of the first LP in patients was higher in the LP simulation group compared to the control group (67% vs 14%, p = 0.0025). The technical assistance was also less frequently needed in the LP simulation group (19% vs 57%, respectively, p = 0.017). The rate of students who participated in this educational study was low.

DISCUSSION

Simulation-based teaching was an effective way to improve students' theoretical and practical knowledge. Whether this approach translates to other procedural skills in real clinical settings merits further study. The low participation rate in the study is due to the fact that students are not used to be included in educational studies and to the complexity of evaluation in routine clinical practice.

Tocolysis compared with no tocolysis in women with threatened preterm birth and ruptured membranes: A propensity score analysis

INTRODUCTION

In women with preterm ruptured membranes and contractions, the administration of tocolysis is controversial. This study compares tocolysis with no tocolysis in women with threatened preterm birth and ruptured membranes.

OBJECTIVE

To compare tocolysis with no tocolysis in women with threatened preterm birth and ruptured membranes.

STUDY DESIGN

Data from the APOSTEL III RCT was combined with data from the National Maternity Hospital, Dublin. In the APOSTEL III trial, women with threatened preterm birth were randomized to atosiban or nifedipine. Patient data from Ireland were obtained from a cohort of women with threatened preterm birth with ruptured membranes. The Irish women received no tocolytic treatment. Only women with ruptured membranes and contractions were selected. We studied women with singleton or twin pregnancies and a gestational age between 25⁺⁰ and 33⁺⁶ weeks. Propensity score matching was performed to create comparable groups. Primary outcome was a composite adverse neonatal outcome. Secondary outcomes were individual components of the primary outcome, as well as neonatal intensive care unit (NICU) admission, gestational age at delivery, prolongation of pregnancy and mode of delivery.

RESULTS

153 women from the Apostel III trial were compared with 51 eligible women of the Irish cohort. We could match 46 women who received tocolysis and 46 women who received no tocolysis. All women had ruptured membranes. Maternal age, BMI, parity and gestational age at study entry were comparable between the groups after matching. There were no statistically significant differences in neonatal composite outcome (9.6 % in the tocolysis group versus 18 % in the control group, OR 0.46, 95 % CI 0.13-1.63). We found a lower incidence of NICU admission in the tocolysis group (63 %) than in the control group (94 %; OR 0.11, 95 % CI 0.03-0.41), which could be explained by differences in national admission policies. There were no statistically significant differences between tocolysis and no tocolysis in any of the other outcomes including sepsis, gestational age at delivery and time to delivery.

CONCLUSION

In this propensity score analysis of women with threatened preterm birth and ruptured membranes, tocolytic therapy did not alter composite adverse neonatal outcome or time to delivery.

Effects of tocolysis with nifedipine or atosiban on child outcome: follow-up of the APOSTEL III trial

OBJECTIVE

To compare the long-term effects of tocolysis with nifedipine or atosiban on child outcome at age 2.5-5.5 years.

DESIGN

The APOSTEL III trial was a multicentre randomised controlled trial that compared tocolysis with nifedipine or atosiban in 503 women with threatened preterm birth. Neonatal outcomes did not differ between both treatment arms, except for a higher incidence of intubation in the atosiban group.

METHODS

Parents were asked to complete four questionnaires regarding neurodevelopment, executive function, behaviour problems and general health.

MAIN OUTCOME MEASURES

The main long-term outcome measure was a composite of abnormal development at the age of 2.5-5.5 years.

RESULTS

Of the 426 women eligible for follow-up, 196 (46%) parents returned the questionnaires for 115 children in the nifedipine group and 110 children in the atosiban group. Abnormal development occurred in 32 children (30%) in the nifedipine group and in 38 children (38%) in the atosiban group (OR 0.74, 95% CI 0.41-1.34). The separate outcomes for neurodevelopment, executive function, behaviour, and general health showed no significant differences between the groups. Sensitivity analysis for all children of the APOSTEL III trial, including a comparison of deceased children, resulted in a higher rate of healthy survival in the nifedipine group (64 versus 54%), but there was no significant difference in the overall mortality rate (5.4 versus 2.7%). There were no significant subgroup effects.

CONCLUSION

Outcomes on broad child neurodevelopment, executive function, behaviour and general health were comparable in both groups. Neither nifedipine nor atosiban can be considered as the preferred treatment for women with threatened preterm birth.

TWEETABLE ABSTRACT

Nifedipine- and atosiban-exposed children had comparable long-term outcomes, including neurodevelopment, executive function and behaviour.

Long-Term Outcomes After Reversible Cerebral Vasoconstriction Syndrome

Background and Purpose—

We aimed to further investigate the long-term outcomes after reversible cerebral vasoconstriction syndrome (RCVS).

Methods—

A longitudinal follow-up study was conducted in 173 RCVS patients.

Results—

Of the 172 patients who completed a mean follow-up of 9.2±3.3 years, 10 had a recurrent RCVS that was benign in all. Independent predictors of relapse were having a history of migraine and having exercise as a trigger for thunderclap headache during initial RCVS. After new delivery, the rate of postpartum RCVS was 9%.

Conclusions—

Overall, long-term outcome after RCVS is excellent.

Concomitant reversible cerebral vasoconstriction syndrome and transient global amnesia

BACKGROUND

Reversible cerebral vasoconstriction syndrome (RCVS) is a common cause of thunderclap headache (TCH), mainly recurrent, sometimes associated with seizures and/or neurological deficit. Association with amnesia is exceptional. We report a case series of RCVS concomitant with transient global amnesia (TGA) and propose pathophysiologic hypotheses.

METHODS

We retrospectively reviewed clinical and radiological features of patients diagnosed with confirmed concomitant RCVS and TGA between 2012 and 2018 in two specialized institutions.

RESULTS

Two women aged 67 and 53, and a 64-year-old man had a first thunderclap headache triggered by an acute emotional stress, rapidly followed by TGA. Amnesia resolved within a few hours and RCVS was proven for all, with complete resolution of vasospasms within 3 months. All three patients had excellent outcome.

CONCLUSIONS

RCVS and TGA can occur simultaneously, which suggests common mechanisms such as aberrant responses to physical or emotional stress and cerebral vasoconstriction.

[Migraine epidemiological, clinical and therapeutic data]

Burden of disease study ranks headache disorders as the second leading cause of years lived with disability worldwide. Migraine has an estimated prevalence of 10 to 14% and is therefore the most common neurological pathology. It concerns young populations, with a female/male ratio of 3/1, and its impact in economic terms is mainly related to indirect costs. Migraine can be episodic or chronic depending on the frequency of headache days (≥ 15 days per month). The diagnosis of migraine is made according to international criteria, which are easy to use, with essential questions to be asked to patients in a logical order and structure. The migraine is explained by an activation of the so-called trigeminocervical system, with release of neuromediators participating in neurogenic inflammation and activation of second-order neurons. Migraine with aura is manifested by neurological symptoms, lasting less than 60 minutes, explained by the phenomenon of cortical spreading depression. Visual symptoms are the most commonly described aura event of migraine, other auras include sensory and speech disturbance. Cortical spreading depression is a slowly propagating wave of near-complete depolarization of neurons and glial cells spreading over the cortex at a speed of ∼3-5 mm/min. First-line acute treatment for migraine consists of nonsteroidal anti-inflammatory drugs (NSAID), triptans and antiemetics. Patients with frequent or chronic headaches warrant prophylactic therapy. Various classes of preventives can be used (β-blockers, tricyclics, antiepileptics), with the choice of therapy tailored to the patient's risk factors and symptoms. In practice, treatment has two axes: NSAID or triptans for crisis treatment and for background treatment prescribed case by case, the first-intention molecules according to the French recommendations are beta-blockers, then, in case of failure, topiramate, oxetorone or amitriptyline.

Evaluation of drug permeability calculation based on luminal disappearance and plasma appearance in the rat single-pass intestinal perfusion model

The rat single-pass intestinal perfusion (SPIP) model is commonly used to investigate gastrointestinal physiology and membrane drug transport. The SPIP model can be used with the intestinal segment inside or outside the abdomen. The rats can also be treated with parecoxib, a selective cycloxygenase-2 inhibitor that has been shown to affect some intestinal functions following abdominal surgery, such as motility, epithelial permeability, fluid flux and ion transport. However, the impact of extra-abdominal placement of the intestinal segment in combination with parecoxib on intestinal drug transport has not been investigated. There is also uncertainty how well intestinal permeability determinations based on luminal drug disappearance and plasma appearance correlate in the rat SPIP model. The main objective of this rat in vivo study was to investigate the effect of intra- vs. extra-abdominal SPIP, with and without, pretreatment with parecoxib. The effect was evaluated by determining the difference in blood-to-lumen ⁵¹Cr-EDTA clearance, lumen-to-blood permeability of a cassette-dose of four model compounds (atenolol, enalaprilat, ketoprofen, and metoprolol), and water flux. The second objective was to compare the jejunal permeability values of the model drugs when determined based on luminal disappearance or plasma appearance. The study showed that the placement of the perfused jejunal segment, or the treatment with parecoxib, had minimal effects on membrane permeability and water flux. It was also shown that intestinal permeability of low permeability compounds should be determined on the basis of data from plasma appearance rather than luminal disappearance. If permeability is calculated on the basis of luminal disappearance, it should preferably include negative values to increase the accuracy in the determinations.

[Post-lumbar puncture syndrome]

This article presents a clinical case which describes some clinical aspects, risk factors, management and the prophylactic methods to prevent the post-lumbar puncture syndrome.

Non-invasive genotyping with a massively parallel sequencing panel for the detection of SNPs in HPA-axis genes

We designed a genotyping panel for the investigation of the genetic underpinnings of inter-individual differences in aggression and the physiological stress response. The panel builds on single nucleotide polymorphisms (SNPs) in genes involved in the three subsystems of the hypothalamic-pituitary-adrenal (HPA)-axis: the catecholamine, serotonin and corticoid metabolism. To promote the pipeline for use with wild animal populations, we used non-invasively collected faecal samples from a wild population of Assamese macaques (Macaca assamensis). We targeted loci of 46 previously reported SNPs in 21 candidate genes coding for elements of the HPA-axis and amplified and sequenced them using next-generation Illumina sequencing technology. We compared multiple bioinformatics pipelines for variant calling and variant effect prediction. Based on this strategy and the application of different quality thresholds, we identified up to 159 SNPs with different types of predicted functional effects among our natural study population. This study provides a massively parallel sequencing panel that will facilitate integrating large-scale SNP data into behavioural and physiological studies. Such a multi-faceted approach will promote understanding of flexibility and constraints of animal behaviour and hormone physiology.

Time-dependent effects on small intestinal transport by absorption-modifying excipients

The relevance of the rat single-pass intestinal perfusion model for investigating in vivo time-dependent effects of absorption-modifying excipients (AMEs) is not fully established. Therefore, the dynamic effect and recovery of the intestinal mucosa was evaluated based on the lumen-to-blood flux (J_abs) of six model compounds, and the blood-to-lumen clearance of ⁵¹Cr-EDTA (CL_Cr), during and after 15- and 60-min mucosal exposure of the AMEs, sodium dodecyl sulfate (SDS) and chitosan, in separate experiments. The contribution of enteric neurons on the effect of SDS and chitosan was also evaluated by luminal coadministration of the nicotinic receptor antagonist, mecamylamine. The increases in J_abs and CL_Cr (maximum and total) during the perfusion experiments were dependent on exposure time (15 and 60 min), and the concentration of SDS, but not chitosan. The increases in J_abs and CL_Cr following the 15-min intestinal exposure of both SDS and chitosan were greater than those reported from an in vivo rat intraintestinal bolus model. However, the effect in the bolus model could be predicted from the increase of J_abs at the end of the 15-min exposure period, where a six-fold increase in J_abs was required for a corresponding effect in the in vivo bolus model. This illustrates that a rapid and robust effect of the AME is crucial to increase the in vivo intestinal absorption rate before the yet unabsorbed drug in lumen has been transported distally in the intestine. Further, the recovery of the intestinal mucosa was complete following 15-min exposures of SDS and chitosan, but it only recovered 50% after the 60-min intestinal exposures. Our study also showed that the luminal exposure of AMEs affected the absorptive model drug transport more than the excretion of ⁵¹Cr-EDTA, as J_abs for the drugs was more sensitive than CL_Cr at detecting dynamic mucosal AME effects, such as response rate and recovery. Finally, there appears to be no nicotinergic neural contribution to the absorption-enhancing effect of SDS and chitosan, as luminal administration of 0.1 mM mecamylamine had no effect.

The effects of three absorption-modifying critical excipients on the in vivo intestinal absorption of six model compounds in rats and dogs

Pharmaceutical excipients that may affect gastrointestinal (GI) drug absorption are called critical pharmaceutical excipients, or absorption-modifying excipients (AMEs) if they act by altering the integrity of the intestinal epithelial cell membrane. Some of these excipients increase intestinal permeability, and subsequently the absorption and bioavailability of the drug. This could have implications for both the assessment of bioequivalence and the efficacy of the absorption-enhancing drug delivery system. The absorption-enhancing effects of AMEs with different mechanisms (chitosan, sodium caprate, sodium dodecyl sulfate (SDS)) have previously been evaluated in the rat single-pass intestinal perfusion (SPIP) model. However, it remains unclear whether these SPIP data are predictive in a more in vivo like model. The same excipients were in this study evaluated in rat and dog intraintestinal bolus models. SDS and chitosan did exert an absorption-enhancing effect in both bolus models, but the effect was substantially lower than those observed in the rat SPIP model. This illustrates the complexity of the AME effects, and indicates that additional GI physiological factors need to be considered in their evaluation. We therefore recommend that AME evaluations obtained in transit-independent, preclinical permeability models (e.g. Ussing, SPIP) should be verified in animal models better able to predict in vivo relevant GI effects, at multiple excipient concentrations.

Oxygen delivered by a high flow concentrator for the treatment of medication-overuse headache

Treatment of medication-overuse headache (MOH) relies on detoxification, during which patients face rebound headache without alternative to painkiller. As oxygen has been proven effective for cluster and other headache subtypes, we sought to evaluate use of normobaric oxygen delivered by a high flow concentrator (HFC) in patients suffering MOH. For this purpose, twenty patients with MOH were included in this prospective monocentric open-labeled feasibility study. All patients received standard care with detoxification in addition to HFC delivering normobaric oxygen at 9 l/min, used to their discretion to treat rebound headache. Primary endpoint was acceptance of HFC and secondary endpoints evaluated its efficacy. Four patients were lost of follow-up after inclusion, one was excluded. HFC was accepted by 14/15 (93.3%). At M6 of follow-up, 15/15 (100%) reverted to episodic headache. In conclusion, normobaric oxygen delivered by HFC appears to be safe, feasible, and probably efficient to help patient with MOH who undergo withdrawal therapy. A larger double-blind, sham-controlled prospective study is needed.

Trial registration: Clinical trials: NCT02302027.

COMT Val158 Met moderates the link between rank and aggression in a non-human primate

The COMT Val¹⁵⁸ Met polymorphism is one of the most widely studied genetic polymorphisms in humans implicated in aggression and the moderation of stressful life event effects. We screened a wild primate population for polymorphisms at the COMT Val¹⁵⁸ Met site and phenotyped them for aggression to test whether the human polymorphism exists and is associated with variation in aggressive behavior. Subjects were all adults from 4 study groups (37 males, 40 females) of Assamese macaques (Macaca assamensis) in their natural habitat (Phu Khieo Wildlife Sanctuary, Thailand). We collected focal animal behavioral data (27 males, 36 females, 5964 focal hours) and fecal samples for non-invasive DNA analysis. We identified the human COMT Val¹⁵⁸ Met polymorphism (14 Met/Met, 41 Val/Met and 22 Val/Val). Preliminary results suggest that COMT genotype and dominance rank interact to influence aggression rates. Aggression rates increased with rank in Val/Val, but decreased in Met/Met and Val/Met individuals, with no significant main effect of COMT genotype on aggression. Further support for the interaction effect comes from time series analyses revealing that when changing from lower to higher rank position Val/Val individuals decreased, whereas Met/Met individuals increased their aggression rate. Contradicting the interpretation of earlier studies, we show that the widely studied Val¹⁵⁸ Met polymorphism in COMT is not unique to humans and yields similar behavioral phenotypes in a non-human primate. This study represents an important step towards understanding individual variation in aggression in a wild primate population and may inform human behavioral geneticists about the evolutionary roots of inter-individual variation in aggression.

Occipital nerve stimulation improves the quality of life in medically-intractable chronic cluster headache: Results of an observational prospective study

Background Occipital nerve stimulation (ONS) has been proposed to treat chronic medically-intractable cluster headache (iCCH) in small series of cases without evaluation of its functional and emotional impacts. Methods We report the multidimensional outcome of a large observational study of iCCH patients, treated by ONS within a nationwide multidisciplinary network ( https://clinicaltrials.gov NCT01842763), with a one-year follow-up. Prospective evaluation was performed before surgery, then three and 12 months after. Results One year after ONS, the attack frequency per week was decreased >30% in 64% and >50% in 59% of the 44 patients. Mean (Standard Deviation) weekly attack frequency decreased from 21.5 (16.3) to 10.7 (13.8) ( p = 0.0002). About 70% of the patients responded to ONS, 47.8% being excellent responders. Prophylactic treatments could be decreased in 40% of patients. Functional (HIT-6 and MIDAS scales) and emotional (HAD scale) impacts were significantly improved, as well as the health-related quality of life (EQ-5D). The mean (SD) EQ-5D visual analogic scale score increased from 35.2 (23.6) to 51.9 (25.7) ( p = 0.0037). Surgical minor complications were observed in 33% of the patients. Conclusion ONS significantly reduced the attack frequency per week, as well as the functional and emotional headache impacts in iCCH patients, and dramatically improved the health-related quality of life of responders.

On the chaotic behavior of the primal-dual affine-scaling algorithm for linear optimization

We study a one-parameter family of quadratic maps, which serves as a template for interior point methods. It is known that such methods can exhibit chaotic behavior, but this has been verified only for particular linear optimization problems. Our results indicate that this chaotic behavior is generic.

Genotyping of non-human primate models: perspectives and challenges for the implementation of the &quot;three R's&quot;

Abstract. Although non-human primates (NHPs) represent only a minor fraction of all animals used in biomedical research, there is a continuous effort to further reduce, refine and replace research with NHPs in accordance with the principles of the three R's. Most of the NHP model species are genetically highly diverse, and significant variation occurs among populations of different geographic origins, particularly in macaques. Since such differences can considerably affect the outcome of biomedical experiments, genotyping represents a promising tool to refine research approaches and to reduce the number of NHPs in biomedical research. Accordingly, the European Primate Network (EUPRIM-Net) developed an anonymous online survey to evaluate possibilities and potential hindrances for the application of genotyping in NHP research. On the one hand, our results point to the importance of genetic variation in NHPs and the need to consider the genetic background for future research approaches. On the other hand, our survey identified several hindrances and limiting factors for the application of genotyping and its incorporation in research, primate husbandry and breeding. We provide some fundamental recommendations on how to meet these challenges and how genotyping can be efficiently used to refine NHP research and to reduce the number of NHPs in biomedical research in the long term.

Levels of PCBs in wild bird eggs: considering toxicity through enzyme induction potential and molecular structure

Polychlorinated biphenyls (PCBs) were analysed in wild bird eggs from industrialised areas in South Africa. The concentration, congener profile, feeding guild, potential associated risk and biology were investigated. PCBs were detected in all eggs with 30 congeners present in more than 80% of the samples. Σ(34)PCB concentrations ranged between 0.9 and 296 ng g(-1) wet weight (ww). The metabolic potential of the PCB metabolic groups showed good agreement with the biodegradability of the individual congeners. Phenobarbital-type (PB-type) inducer PCBs were prevalent, indicating the predominance of less toxic PCB congeners. However, non-ortho PCBs which were not included in the current analyses, could affect the toxic potential of the PCBs in the eggs requiring more investigation. Although the current levels of PCBs measured do not indicate a health risk to the birds assessed, the presence of mono-ortho PCBs at appreciable levels motivates for the assessment of dioxin-like chemicals in wild bird eggs.