Transcatheter pulmonary valve replacement after pulmonary homograft dysfunction

Pulmonary homograft dysfunction is challenging to treat in patients with a previous Ross procedure, and results in significant morbidity and mortality in case of reoperation. We report the case of a patient with early severe pulmonary homograft stenosis 18 months after a Ross procedure and successful management using transcatheter pulmonary valve replacement.

Segmentation of 4D Flow MRI: Comparison between 3D Deep Learning and Velocity-Based Level Sets

A thoracic aortic aneurysm is an abnormal dilatation of the aorta that can progress and lead to rupture. The decision to conduct surgery is made by considering the maximum diameter, but it is now well known that this metric alone is not completely reliable. The advent of 4D flow magnetic resonance imaging has allowed for the calculation of new biomarkers for the study of aortic diseases, such as wall shear stress. However, the calculation of these biomarkers requires the precise segmentation of the aorta during all phases of the cardiac cycle. The objective of this work was to compare two different methods for automatically segmenting the thoracic aorta in the systolic phase using 4D flow MRI. The first method is based on a level set framework and uses the velocity field in addition to 3D phase contrast magnetic resonance imaging. The second method is a U-Net-like approach that is only applied to magnitude images from 4D flow MRI. The used dataset was composed of 36 exams from different patients, with ground truth data for the systolic phase of the cardiac cycle. The comparison was performed based on selected metrics, such as the Dice similarity coefficient (DSC) and Hausdorf distance (HD), for the whole aorta and also three aortic regions. Wall shear stress was also assessed and the maximum wall shear stress values were used for comparison. The U-Net-based approach provided statistically better results for the 3D segmentation of the aorta, with a DSC of 0.92 ± 0.02 vs. 0.86 ± 0.5 and an HD of 21.49 ± 24.8 mm vs. 35.79 ± 31.33 mm for the whole aorta. The absolute difference between the wall shear stress and ground truth slightly favored the level set method, but not significantly (0.754 ± 1.07 Pa vs. 0.737 ± 0.79 Pa). The results showed that the deep learning-based method should be considered for the segmentation of all time steps in order to evaluate biomarkers based on 4D flow MRI.

Optimal Timing of Coronary Artery Bypass Grafting in Haemodynamically Stable Patients after Myocardial Infarction

During the acute phase of myocardial infarction, the culprit artery must be revascularized quickly with angioplasty. Surgery then completes the procedure in a second stage. If emergency surgery is performed, the resulting death rate is high; 15-20% of patients are operated on within the first 48 h after the myocardial infarction. The timing of surgical revascularization and the patient's preoperative state influence the mortality rate. We aimed to evaluate the impact of surgery delay on morbimortality. Between 2007 and 2017, a retrospective monocentric study was conducted including 477 haemodynamically stable patients after myocardial infarction who underwent an urgent coronary bypass. Three groups were described, depending on the timing of the surgery: during the first 4 days (Group 1, n = 111, 23%), 5 to 10 days (Group 2, n = 242, 51%) and after 11 days (Group 3, n = 124, 26%). The overall thirty-day mortality was 7.1% (n = 34). The death rate was significantly higher in Group 1 (n = 16; 14% vs. n = 10; 4.0% vs. n = 8; 6%, p < 0.01). The mortality risk factors identified were age (OR: 1.08; CI 95%: 1.04-1.12; p < 0.001), peripheral arteriopathy (OR: 3.31; CI 95%: 1.16-9.43; p = 0.024), preoperative renal failure (OR: 6.39; CI 95%: 2.49-15.6; p < 0.001) and preoperative ischemic recurrence (OR: 3.47; CI 95%: 1.59-7.48; p < 0.01). Ninety-two patients presented with preoperative ischemic recurrence (19%), with no difference between the groups. The optimal timing for the surgical revascularization of MI seems to be after Day 4 in stable patients. However, timing is not the only factor influencing the death rate: the patient's health condition and disease severity must be considered in the individual management strategy.

1186 IMPROVED PERFORMANCE AGAINST SSNAP PARAMETERS FOR THROMBOLYSED STROKE PATIENTS FOLLOWING CHANGES IN PRACTICE

Background

The CQC inspection of the Royal Lancaster Infirmary (RLI) in May 2021 rated the performance of the stroke department unsatisfactory, leading to a number of changes. A retrospective audit was performed to determine the impact of these changes for thrombolysed stroke patients.

Aim

This retrospective audit assessed the performance of the stroke department at the RLI against the parameters set by the ‘Sentinel Stroke National Audit Program’ (SSNAP), comparing 6-month periods before and after the CQC inspection in May 2021.

Method

Using electronic medical records and SSNAP data, we reviewed every thrombolysed stroke patient at the RLI between November 2020 until April 2021 and from May 2021 until November 2021, assessing 10 parameters and comparing the results with SSNAP targets. Since May 2021, changes to practice introduced included opening a new, larger stroke unit located directly opposite the Emergency Department, ring-fencing stroke beds, doubling the number of stroke specialists and stroke consultants reviewing all suspected stroke patients face-to-face within working hours.

Results

46 patients were thrombolysed with 42 confirmed as having had ischaemic strokes on subsequent MRI imaging. All patients were discussed with a stroke consultant before thrombolysis. Mean time from arrival to CT improved from 51 to 34.5 minutes, admission to stroke unit from 7hr53 to 4hr36 and to thrombolysis from 2hr18 to 1hr22. The number of thrombolysis complications decreased from 5 to 2. Since the changes, the SSNAP grade for stroke unit admission improved from C to A and specialist assessments from E to B.

Conclusion

The changes implemented following the May 2021 CQC inspection have had a positive impact on the care of thrombolysed stroke patients and overall SSNAP grades at RLI. Improvements are still required and the next steps include improving the efficiency of thrombolysis times and further improving SSNAP grades.

Dynamical interactions reconfigure the gradient of cortical timescales

The functional organization of the brain is usually presented with a back-to-front gradient of timescales, reflecting regional specialization with sensory areas (back) processing information faster than associative areas (front), which perform information integration. However, cognitive processes require not only local information processing but also coordinated activity across regions. Using magnetoencephalography recordings, we find that the functional connectivity at the edge level (between two regions) is also characterized by a back-to-front gradient of timescales following that of the regional gradient. Unexpectedly, we demonstrate a reverse front-to-back gradient when nonlocal interactions are prominent. Thus, the timescales are dynamic and can switch between back-to-front and front-to-back patterns.

Trends of Myocarditis and Endocarditis Cases before, during, and after the First Complete COVID-19-Related Lockdown in 2020 in France

Background. The impact of the COVID-19 pandemic on hospitalization for cardiac infections is not well known. We aimed to evaluate the nationwide trends in hospital stays for myocarditis and endocarditis cases before, during and after the nationwide lockdown for the COVID-19 pandemic in France. We then aimed to describe the proportion of myocarditis and endocarditis patients with and without COVID-19 and their clinical characteristics. Methods. Hospitalized cases of cardiac infection were extracted from the French National Discharge database, which collects the medical records of all patients discharged from all public and private hospitals in France. Age, sex, and available cardiovascular risk factors were compared between stays with and without COVID-19 during the lockdown. Results. The number of myocarditis cases was 11% higher in 2020, compared to the average of the three prior years. In 2020, 439 of 3727 cases of myocarditis were associated with COVID-19. For endocarditis, there was an increase in cases by 7% in 2020 versus prior years. For endocarditis, 3% (240 of 8128 cases) of patients with endocarditis had COVID-19. For myocarditis, older age, hypertension, diabetes, obesity, and atrial fibrillation were more frequent in patients with COVID-19 than in those without. For endocarditis, only hypertension was more frequent in patients with COVID-19 than in those without. Conclusion. Our study reports an increase in hospitalizations for both myocarditis and endocarditis in 2020, possibly related to the COVID-19 pandemic. Interestingly, the trends differ according to the COVID-19 status. Knowledge of the factors associating myocarditis or endocarditis and COVID-19 may improve the quality and the type of monitoring for people with COVID-19, the identification of patients at risk of cardiac infections, and the treatment of COVID-19 patients.

[Comparative analysis of the brain distribution of [18F]FDG in populations of patients with Alzheimer's disease with or without family history of dementia]

Hereditary forms of Alzheimer's disease (AD) and early-onset forms have more brain damage than sporadic or late-onset forms at the time of diagnosis (1, 2). Data in the literature are contradictory concerning familial forms without known heredity or mutation. The aim of this study was to compare the brain distribution of FDG between two populations of patients with a clinical diagnosis of sporadic AD according to the presence or not of a first degree family history of dementia. We retrospectively included 243 patients with clinical diagnosis of AD who underwent brain FDG PET imaging between 2012 and 2017. SPM12 was used to compare the FDG brain distribution in 199 patients with AD and no familial history of dementia and 43 patients with AD and first degree familial history of dementia. Compared to a database of 22 healthy control subjects, both groups of AD patients showed a significant decrease of FDG distribution in temporo-parietal, posterior cingulate and posterior left frontal cortex with respect to the controls (p inferior to 0.05 corrected for the family-wise error, pFWE-corr). There were no significant differences between the two AD groups (pFWE-corr superior to 0.05 and p superior to 0.001 uncorrected for multiple comparisons) that present the same brain metabolic pathology.

Cardiovascular Surgical Emergencies in France, before, during and after the First Lockdown for COVID-19 in 2020: A Comparative Nationwide Retrospective Cohort Study

Background: There are still gaps regarding the impact of the nationwide lockdown on non-COVID-19 emergency hospitalizations. This study aims to describe the trends in hospitalizations for cardiovascular surgical emergencies in France, before, during and after the first lockdown. Materials and Methods: All adults admitted for mechanical complications of myocardial infarction (MI), aortic dissection, aortic aneurysm rupture, acute and critical limb ischemia, circulatory assistance, heart transplantation and major amputation were included. This retrospective cohort study used the French National Hospital Discharge database. The numbers of hospitalizations per month in 2020 were compared to the previous three years. Results: From January to September 2020, 94,408 cases of the studied conditions were reported versus 103,126 in the same period in 2019 (−8.5%). There was a deep drop in most conditions during the lockdown, except for circulatory assistance, which increased. After the lockdown, mechanical complications of MI and aortic aneurysm rupture increased, and cardiac transplantations declined compared with previous years. Conclusion: We confirmed a deep drop in most cardiovascular surgical emergencies during the lockdown. The post-lockdown period was characterized by a small over-recovery for mechanical complications of MI and aortic aneurysm rupture, suggesting that many patients were able to access surgery after the lockdown.

Quality improvement Initiative to eliminate silver precipitate during Periodic Acid Silver Methenamine Stain (PAMS) automated protocol of renal biopsies at McGill University Health Centre

Introduction/Objective

Annually, about 400 renal biopsies are processed at the McGill University Health Centre (MUHC) pathology laboratory located in Montreal, Canada. One of the stains used to visualize the glomerular basement membrane is Periodic Acid Silver Methenamine Stain (PAMS). In August 2020, a strong, granular precipitate of silver was noted during PAMS automated staining resulting in uninterpretable results and delay in the diagnosis. Based on a sample analysis, this problem affected 21 % of kidney biopsies.

Methods/Case Report

A cause-and-effect workflow was developed for systematic assessment of potential causes of the granular precipitate including pre-analytical and analytical factors. Some of the pre-analytical factors included length of time spent in transport before fixation and patient factors that predisposed precipitate formation. Analytical factors were categorized as fixation problems (temperature, pH, duration), embedding problems (parafilm temperature, cooling method, type of parafilm), slide preparation (temperature, water bath pH, dehydration and further processing steps), microtone parameters (microtone calibration, thickness, laboratory technologist expertise), automatic staining parameters (cartridge age, hematoxylin counterstain duration, wash-out period etc.) and coverslip placement (adhesive type, temperature, drying).

Results (if a Case Study enter NA)

Following our systematic approach, the cause of granular precipitate was identified as the timing of hematoxylin counterstain. A portion of renal biopsy tissue was taken from parafilm blocks of previouslly reported cases of patients with membranous glomerulonephritis to further test the hypothesis by introduction of various incubation times with the hematoxylin counterstain.

Conclusion

Best PAMS staining was attained when no hematoxylin counterstain was employed (instead, neutral red counterstain for 70 seconds was used). PAMS staining with hematoxylin counter stain for no more than 60 seconds was found to be acceptable for the interpretation of glomerular pathology.

Effects of Age, Level of Education and HIV Status on Cognitive Performance in West African Older Adults: The West Africa IeDEA Cohort Collaboration

An in-depth understanding of the impact of aging, cognitive reserve, and HIV status on cognitive function is needed in older West African adults. Ninety-nine HIV-negative and 334 HIV-positive adults aged ≥ 50 years were enrolled in three clinics (Senegal and Côte d'Ivoire) participating in the IeDEA West Africa collaboration. All subjects underwent the Free and Cued Selective Reminding Test (FCSRT) and the Isaacs Set Test (IST). Age (both linear and quadratic), education level, and HIV status effects on Z-scores were assessed using multivariate linear regression models. Interactions between HIV status and age or educational level were tested. In the present cohort of older West African adults, the role of age and educational level on episodic memory and verbal fluency was observed without revealing an interaction between HIV status and age effect. As age had quadratic effects, older HIV-positive adults should not be considered as a unique group irrespective of their age. Low-educated HIV-positive patients had the lowest verbal fluency performance compared to others. Further studies are needed to duplicate these results. In clinical settings, screening and adapted programs focusing on improving cognition in those patients are needed.

Comparison of two techniques (in vivo and ex-vivo) for evaluating the elastic properties of the ascending aorta: Prospective cohort study

Introduction

Aneurysms of the ascending aorta (AA) correspond to a dilatation of the ascending aorta that progressively evolves over several years. The main complication of aneurysms of the ascending aorta is type A aortic dissection, which is associated with very high rates of morbidity and mortality. Prophylactic ascending aorta replacement guidelines are currently based on maximal AA diameter. However, this criterion is imperfect. Stretching tests on the aorta carried out ex-vivo make it possible to determine the elastic properties of healthy and aneurysmal aortic fragments (tension test, resistance before rupture). For several years now, cardiac magnetic resonance imaging (MRI) has provided another means of evaluating the elastic properties of the aorta. This imaging technique has the advantage of being non-invasive and of establishing aortic compliance (local measurement of stiffness) without using contrast material by measuring the variation of the aortic surface area during the cardiac cycle, and pulse wave velocity (overall stiffness of the aorta).

Materials and methods

Prospective single-center study including 100 patients with ascending aortic aneurysm requiring surgery. We will perform preoperative cine-MRI and biomechanical laboratory stretching tests on aortic samples collected during the cardiac procedure. Images will be acquired with a 3T MRI with only four other acquisitions in addition to the conventional protocol. These additional sequences are a Fast Low Angle Shot (FLASH)-type sequence performed during a short breath-hold in the transverse plane at the level of the bifurcation of the pulmonary artery, and phase-contrast sequences that encodes velocity at the same localization, and also in planes perpendicular to the aorta at the levels of the sino-tubular junction and the diaphragm for the descending aorta. For ex-vivo tests, the experiments will be carried out by a biaxial tensile test machine (ElectroForce®). Each specimen will be stretched with 10 times of 10% preconditioning and at a rate of 10 mm/min until rupture. During the experiment, the tissue is treated under a 37°C saline bath. The maximum elastic modulus from each sample will be calculated.

Results

The aim of this study is to obtain local patient-specific elastic modulus distribution of the ascending aorta from biaxial tensile tests and to assess elastic properties of the aorta using MRI, then to evaluate the correlation between biaxial tests and MRI measurements.

Discussion

Our research hypothesis is that there is a correlation between the evaluation of the elastic properties of the aorta from cardiac MRI and from stretching tests performed ex-vivo on aorta samples collected during ascending aorta replacement.

A tensed Tendyne

We report a case of prosthesis dislodgement after transcatheter mitral valve replacement in an 85-year-old woman with chronic ischaemic heart failure. Two weeks after an initial successful implantation, she presented with a paravalvular leak associated with left ventricular outflow tract obstruction. Tether re-tensioning was performed and resolved the situation, but resulted in a deformation of the apical attachment zone into the left ventricle. Unfortunately, the patient finally expired from severe endocarditis. Proper anchoring is the main challenge for transcatheter mitral valve replacement techniques. Dislodgement of the prosthesis after transcatheter mitral valve replacement is an infrequent complication of the Tendyne® procedure. This case emphasizes the importance of assessing the quality of the myocardium at the implantation zone of the apical pad, and of prosthesis oversizing, especially if low-profile valves are chosen. .

Diversity of cyanobacteria from thermal muds (Balaruc-Les-Bains, France) with the description of Pseudochroococcus coutei gen. nov., sp. nov

Cyanobacteria are able to synthesize a high diversity of natural compounds that account for their success in the colonization of a variety of ecological niches. Many of them have beneficial properties. The mud from the thermal baths of Balaruc-Les-Bains, one of the oldest thermal baths in France, has long been recognized as a healing treatment for arthro-rheumatic diseases. To characterize the cyanobacteria living in these muds, several strains were isolated from the water column and biofilms of the retention basin and analyzed using a polyphasic approach. Morphological, ultrastructural and molecular (16S rRNA gene and 16S-23S ITS region sequencing) methods were employed to identify nine cyanobacterial strains belonging to the orders Chroococcales, Synechococcales, Oscillatoriales and Nostocales. The combination of morphological and genetic characteristics supported the description of a new genus and species with the type species as Pseudochroococcus coutei. The taxonomic diversity in the muds from Thermes de Balaruc-Les-Bains appears higher than previously documented, providing new candidate taxa for their observed therapeutic properties.

Evaluation of neurosurgical training of French military surgeons prior to their deployment

BACKGROUND

A specific training course was formalized in 2007 in order to facilitate the management of cranio-encephalic injuries by French military general surgeons during deployment, within the Advanced Course for Deployment Surgery (ACDS). The objective is to evaluate the neurosurgical pre-deployment training course attended by the military surgeons.

METHODS

From June 2019 to September 2019, we conducted a cross-sectional survey in the form of a digital self-completed questionnaire, addressed to all graduated military surgeons working in the French Military Training Hospitals. The survey included: (1) a knowledge assessment; and (2) a self-assessment of the training course. The participating surgeons were classified into two groups according to their participation (group 1) or not (group 2) in the neurosurgical module. The main outcome was the score received on the knowledge assessment.

RESULTS

Among the 145 military surgeons currently in service, 76 participated in our study (53%), of which 49 were classified in group 1 (64%) and 27 in group 2 (36%). Group 1 surgeons had a significantly higher score than Group 2 at the knowledge assessment (mean 21.0±7.1 vs. 17.8±6.0, P=0.041). The most successful questions were related to TBI diagnosis and surgical technique, while the least successful questions dealt with "beyond emergency care" and surgical indications.

CONCLUSION

The French pre-deployment neurosurgical training course provides a strong neurosurgical background, sufficient to perform life-saving procedures in a modern conflict situation. However, neurosurgical specialized advice should be solicited whenever possible to assist the in-theatre surgeon in surgical decisions.

The infragluteal fold: An appraisal by MRI combined with an anatomic study

PURPOSE

The gluteal region is a key element of beauty balance and sexual appearance. However, there is no clear anatomical description of the infragluteal fold, nor any classification exists allowing standardizing treatment of this area in case of jeopardisation. The purpose of this study was to perform an anatomical description of the infragluteal fold (IGF) matching radiological and anatomical findings in describing specifically raise of the fibrous component at the bone level.

METHODS

Six volunteers (three males and three females) underwent an MRI scan (Siemens Aera® 1.5 T) of the pelvic region. T1 Vibe Morpho T2, Sag Space 3D, and Millimetric slices were performed in order to obtain a more detailed selection of the gluteal landmark. Trabecular connective tissue of the region was analyzed using Horos® ROI (region of interest) segmentation function. Four fresh cadavers (two males, two females, accounting for 8 hemipelvis) were dissected in order to compare the radiological findings.

RESULTS

The infragluteal fold is a connectival fibrous band extending from the ramus of the ischium (but not involving the ischial tuberosity, for a length of 21 mm ± 2 and 21 mm ± 3), the apex of the sacrum (for a length of 13 ± 2 and 11 mm ± 2), and the coccyx (for a length of 19 mm ± 2 and 20 mm ± 2, all measures referring to volunteers and cadavers, respectively) reaching superficially the dermis of the medial one-third of the cutaneous fold. No significant difference was found between volunteer and cadaver group in MRI measurement of bony origins, or between MRI and cadaveric dissection measurements.

CONCLUSION

Knowledge of this structure will define novel surgical techniques in infragluteal fold restoration.

[Normal childbirth: physiologic labor support and medical procedures. Guidelines of the French National Authority for Health (HAS) with the collaboration of the French College of Gynaecologists and Obstetricians (CNGOF) and the French College of Midwives (CNSF) -- Text of the Guidelines (short text)]

OBJECTIVE

The objective of these guidelines is to define for women at low obstetric risk modalities that respect the physiology of delivery and guarantee the quality and safety of maternal and newborn care.

METHODS

These guidelines were made by a consensus of experts based on an analysis of the scientific literature and the French and international recommendations available on the subject.

RESULTS

It is recommended to conduct a complete initial examination of the woman in labor at admission (consensus agreement). The labor will be monitored using a partogram that is a useful traceability tool (consensus agreement). A transvaginal examination may be offered every two to four hours during the first stage of labor and every hour during the second stage of labor or before if the patient requests it, or in case of a warning sign. It is recommended that if anesthesia is required, epidural or spinal anesthesia should be used to prevent bronchial inhalation (grade A). The consumption of clear fluids is permitted throughout labor in patients with a low risk of general anesthesia (grade B). It is recommended to carry out a "low dose" epidural analgesia that respects the experience of delivery (grade A). It is recommended to maintain the epidural analgesia through a woman's self-administration pump (grade A). It is recommended to give the woman the choice of continuous (by cardiotocography) or discontinuous (by cardiotocography or intermittent auscultation) monitoring if the conditions of maternity organization and the permanent availability of staff allow it and, after having informed the woman of the benefits and risks of each technique (consensus agreement). In the active phase of the first stage of labor, the dilation rate is considered abnormal if it is less than 1cm/4h between 5 and 7cm or less than 1cm/2h above 7cm (level of Evidence 2). It is then recommended to propose an amniotomy if the membranes are intact or an oxytocin administration if the membranes are already ruptured, and the uterine contractions considered insufficient (consensus agreement). It is recommended not to start expulsive efforts as soon as complete dilation is identified, but to let the presentation of the fetus drop (grade A). It is recommended to inform the gynecologist-obstetrician in case of nonprogression of the fetus after two hours of complete dilation with sufficient uterine dynamics (consensus agreement). It is recommended not to use abdominal expression (grade B). It is recommended to carry out preventive administration of oxytocin at 5 or 10 IU to prevent PPH after vaginal delivery (grade A). In the case of placental retention, it is recommended to perform a manual removal of the placenta (grade A). In the absence of bleeding, it should be performed 30minutes but not more than 60minutes after delivery (consensus agreement). It is recommended to assess at birth the breathing or screaming, and tone of the newborn to quickly determine if resuscitation is required (consensus agreement). If the parameters are satisfactory (breathing present, screaming frankly, and normal tonicity), it is recommended to propose to the mother that she immediately place the newborn skin-to-skin with her mother if she wishes, with a monitoring protocol (grade B). Delayed cord clamping is recommended beyond the first 30seconds in neonates, not requiring resuscitation (grade C). It is recommended that the first oral dose (2mg) of vitamin K (consensus agreement) be given systematically within two hours of birth.

CONCLUSION

These guidelines allow women at low obstetric risk to benefit from a better quality of care and optimal safety conditions while respecting the physiology of delivery.

Aortic root remodeling with external annuloplasty for acute type A aortic dissection: Midterm results

BACKGROUND

To evaluate the role of aortic root remodeling with external aortic annuloplasty (ARREAA) in acute type A aortic dissection (AAAD).

METHODS

From May 2011 to May 2020, 59 patients out of 240 with AAAD underwent ARREAA. Data were retrospectively collected and analyzed.

RESULTS

The mean age was 61.4 ± 8.6 years and 43 patients were males (73%). Hemiarch and total arch replacement were performed in 37 (62.7%) and 14 (23.7%) patients. An aortic valvuloplasty was performed in seven patients (11.8%). Five patients (8.5%) required coronary artery bypass graft. Re-exploration for bleeding was required in six patients (10.1%). The 30-day mortality rate was 18.6%. Preoperative hemodynamic instability (odds ratio [OR] = 8.57, 95% confidence interval [CI] = 1.57-46.71; p = 0.013), consciousness disorder (OR = 19.18, 95% CI = 3.02-121.72]; p = 0.002) or myocardial ischemia (OR = 6.28, 95% CI = 1.27-31.10; p = 0.013) were significantly associated with postoperative mortality. No patient was reoperated for aortic valve during the postoperative period. One patient suffered a stroke postoperatively with partial recovery. Kidney failure requiring temporary dialysis occurred in 12 patients (20.3%). At discharge, a transthoracic echocardiogram showed moderate aortic regurgitation (AR; grade 2) in two patients. During follow-up (mean = 58.4 ± 32.4 months), three patients died. The rate of mortality was 6.2%. Actuarial survival at 5 years was 76.3%. No patient required reoperation on the proximal aorta or aortic valve. At 4 years, freedom from any aortic valve or root reintervention and AR > 2 were both 100%.

CONCLUSION

In a center with expertise in valve-sparing procedures, ARREAA is a reasonable option in the surgical management of AAAD in selected patients. This technique stabilizes the aortic annulus and preserves root anatomy for durable outcomes.

The circadian dynamics of the hippocampal transcriptome and proteome is altered in experimental temporal lobe epilepsy

Gene and protein expressions display circadian oscillations, which can be disrupted in diseases in most body organs. Whether these oscillations occur in the healthy hippocampus and whether they are altered in epilepsy are not known. We identified more than 1200 daily oscillating transcripts in the hippocampus of control mice and 1600 in experimental epilepsy, with only one-fourth oscillating in both conditions. Comparison of gene oscillations in control and epilepsy predicted time-dependent alterations in energy metabolism, which were verified experimentally. Although aerobic glycolysis remained constant from morning to afternoon in controls, it increased in epilepsy. In contrast, oxidative phosphorylation increased in control and decreased in epilepsy. Thus, the control hippocampus shows circadian molecular remapping, which is altered in epilepsy. We suggest that the hippocampus operates in a different functioning mode in epilepsy. These alterations need to be considered when studying epilepsy mechanisms, designing drug treatments, and timing their delivery.

Crystalline defects in bulk metallic glasses: consequences on fracture toughness determination and ductility

Dating back to the late 1980s, bulk metallic glasses (BMGs) are relatively new materials that exhibit exceptional mechanical properties (strength, hardness, fracture toughness, stored elastic energy …), compared to those of most crystalline metallic alloys. Their apparent brittleness under uniaxial loading, however, is still a major obstacle to their industrialization. Moreover, BMGs often contain crystalline defects developed, intentionally or not, during their complex and delicate elaboration. These flaws are known to affect their fracture toughness and their plastic behavior. This paper reviews twenty years of works about this subject on Zr-based BMGs that may contain a low volume fraction of crystalline defects of different natures, e.g. dendrites or spherulites, depending on the synthesis method. Dedicated experimental set-ups, mainly bending tests on notched beams, were developed to create in the specimen a proper pre-crack by fatigue and then load it monotonically up to fracture. The measured fracture toughness and the fractographic observations allow to conclude that these crystalline defects facilitate pre-cracking, but result in an embrittlement that is more or less significant depending on their type. The loading mode of the crack - mode I, II or mixed - as well as the temperature were shown to play a key role in crack initiation and propagation, whether steadily or catastrophically, in the BMG. By means of finite element computations analyses, explanations on how the crystalline flaws presence can affect fracture toughness and perturbate crack growth, under mode I and mode II, were proposed. Finally, the relevance of these experimental techniques as well as the link between crystalline defects, fracture toughness and their consequences on the ductility of a structural component are discussed.

Lessons for the clinical nephrologist: a rare case of unfused renal ectopia

Right crossed inferior unfused renal ectopia is a rare developmental anomaly in which both kidneys are located on the left side of the body. It's the result of a halt in migration of kidneys to their normal location during the embryonic period and in ureteral bud faulty that migrates to the opposite side and induces the metanephric blastema on the wrong side. In this article, we aim to review embryology and complete description of renal ectopia anatomy and describe a rare case of right crossed unfused inferior renal ectopia with a left lower kidney artery originated directly from an abdominal aortic aneurism (AAA). The treatment consisted in AAA's exclusion with a custom-made endograft device shaped on purpose with a dedicated branch allowing perfusion of the ectopic lower left kidney.

Multidisciplinary advisory teams to manage multidrug-resistant tuberculosis: the example of the French Consilium

SETTING: The World Health Organization (WHO) recommends that multidrug-resistant tuberculosis (MDR-TB) treatment should be managed in collaboration with multidisciplinary advisory committees (consilia). A formal national Consilium has been established in France since 2005 to provide a centralised advisory service for clinicians managing MDR-TB and extensively drug-resistant (XDR-TB) cases.OBJECTIVE: Review the activity of the French TB Consilium since its establishment.DESIGN: Retrospective description and analysis of the activity of the French TB Consilium.RESULTS: Between 2005 and 2016, 786 TB cases or contacts of TB cases were presented at the French TB Consilium, including respectively 42% and 79% of all the MDR-TB and XDR-TB cases notified in France during this period. Treatment regimens including bedaquiline and/or delamanid were recommended for 42% of the cases presented at the French TB Consilium since 2009. Patients were more likely to be presented at the French TB Consilium if they were born in the WHO Europe Region, had XDR-TB, were diagnosed in the Paris region, or had resistance to additional drugs than those defining XDR-TB.CONCLUSION: The French TB Consilium helped supervise appropriate management of MDR/XDR-TB cases and facilitated implementation of new drugs for MDR/XDR-TB treatment.

Graphene oxide/waterborne polyurethane nanocoatings: effects of graphene oxide content on performance properties

Graphene oxide (GO) is a good nanofiller candidate for waterborne coatings because of its outstanding physical and mechanical properties, good dispersibility in water, and low cost relative to graphene. Here, we report on the performance of a one-part, waterborne polyurethane (WPU) nanocoating formulated with four different GO loadings ([0.4% to 2.0%] by mass). The degree of GO dispersion/adhesion was evaluated using scanning electron microscopy, laser scanning confocal microscopy, and Raman microscopy. Nanocoating performance was evaluated using a dynamic mechanical thermal analyzer for mechanical properties, a customized coulometric permeation apparatus for oxygen barrier properties, a combustion microcalorimeter for flammability, a hot disk analyzer for thermal conductivity, thermogravimetric analysis for thermal stability, and a moisture sorption analyzer for water uptake. The results show that GO sheets were well dispersed in, and have good adhesion to, WPU. At the higher mass loadings ([1.2% or 2%] by mass), GO increased the modulus and yield strength of WPU by 300% and 200%, respectively, increased the thermal conductivity by 38%, reduced the burning heat release rate (flammability) by 43%, and reduced the oxygen permeability by up to sevenfold. The presence of GO, however, increased water vapor uptake at high humidity; the moisture content of 2% mass loading GO/WPU nanocoatings at 90% RH was almost twice that of the moisture content for unfilled WPU. Overall, with the exception of water uptake at very high humidity (> 70% RH), the observed improvements in physical and mechanical properties combined with the ease of processing suggest that GO is a viable nanofiller for WPU coatings.

Risk factors for extensive drug resistance in multidrug-resistant tuberculosis cases: a case-case study

SETTINGS

Identification of extensively drug-resistant tuberculosis (XDR-TB) may be delayed because of the lack of availability of molecular testing for second-line drugs (SLDs). Early suspicion of XDR-TB is therefore necessary to avoid developing further drug resistance.

OBJECTIVE

To identify the characteristics associated with XDR-TB among multidrug-resistant TB (MDR-TB) cases before the availability of second-line drug susceptibility testing (DST) results.

METHODS

All MDR-TB cases with available second-line DST results recorded in France from 1998 to 2013 were classified as simple MDR-TB (no resistance to fluoroquinolones [FQs] or second-line injectable drugs [SLIDs]), pre-XDR-TB (resistance to FQs or SLIDs) and XDR-TB cases (resistance to both).

RESULTS

A total of 833 MDR-TB cases were analysed, including 168 (20%) pre-XDR and 62 (7%) XDR-TB cases. A previous history of treatment was acknowledged among 41% of the cases; 12% were human immunodeficiency virus-positive. Characteristics independently associated with XDR-TB were foreign birth (OR 9.5), previous anti-tuberculosis treatment (OR 2.6), smear positivity (OR 4.5) and ethambutol (EMB) resistance (OR 9.1). Characteristics independently associated with pre-XDR-TB compared to simple MDR-TB cases were male sex (OR 1.6), birth in Europe (OR 2.6) and EMB resistance (OR 1.9).

CONCLUSION

The presence of clinical or bacteriological characteristics associated with XDR-TB should lead to rapid molecular testing for resistance to SLDs before starting tailored treatment.

Very Low Phytoplankton Diversity in a Tropical Saline-Alkaline Lake, with Co-dominance of Arthrospira fusiformis (Cyanobacteria) and Picocystis salinarum (Chlorophyta)

Lake Dziani Dzaha (Mayotte Island, Indian Ocean) is a tropical thalassohaline lake which geochemical and biological conditions make it a unique aquatic ecosystem considered as a modern analogue of Precambrian environments. In the present study, we focused on the diversity of phytoplanktonic communities, which produce very high and stable biomass (mean_2014-2015 = 652 ± 179 μg chlorophyll a L^-1). As predicted by classical community ecology paradigms, and as observed in similar environments, a single species is expected to dominate the phytoplanktonic communities. To test this hypothesis, we sampled water column in the deepest part of the lake (18 m) during rainy and dry seasons for two consecutive years. Phytoplanktonic communities were characterized using a combination of metagenomic, microscopy-based and flow cytometry approaches, and we used statistical modeling to identify the environmental factors determining the abundance of dominant organisms. As hypothesized, the overall diversity of the phytoplanktonic communities was very low (15 OTUs), but we observed a co-dominance of two, and not only one, OTUs, viz., Arthrospira fusiformis (Cyanobacteria) and Picocystis salinarum (Chlorophyta). We observed a decrease in the abundance of these co-dominant taxa along the depth profile and identified the adverse environmental factors driving this decline. The functional traits measured on isolated strains of these two taxa (i.e., size, pigment composition, and concentration) are then compared and discussed to explain their capacity to cope with the extreme environmental conditions encountered in the aphotic, anoxic, and sulfidic layers of the water column of Lake Dziani Dzaha.

Characterization of phototrophic microorganisms and description of new cyanobacteria isolated from the saline-alkaline crater-lake Dziani Dzaha (Mayotte, Indian Ocean)

The saline-alkaline crater-lake Dziani Dzaha (Mayotte, Indian Ocean) is dominated by the bloom-forming cyanobacterium Arthrospira. However, the rest of the phototrophic community remains underexplored because of their minute dimension or lower biomass. To characterize the phototrophic microorganisms living in this ecosystem considered as a modern analog of Precambrian environments, several strains were isolated from the water column and stromatolites and analyzed using the polyphasic approach. Based on morphological, ultrastructural and molecular (16S rRNA gene, 18S rRNA gene, 16S-23S internal transcribed spacer (ITS) region and cpcBA-IGS locus) methods, seven filamentous cyanobacteria and the prasinophyte Picocystis salinarum were identified. Two new genera and four new cyanobacteria species belonging to the orders Oscillatoriales (Desertifilum dzianense sp. nov.) and Synechococcales (Sodalinema komarekii gen. nov., sp. nov., Sodaleptolyngbya stromatolitii gen. nov., sp. nov. and Haloleptolyngbya elongata sp. nov.) were described. This approach also allowed to identify Arthrospira fusiformis with exclusively straight trichomes instead of the spirally coiled form commonly observed in the genus. This study evidenced the importance of using the polyphasic approach to solve the complex taxonomy of cyanobacteria and to study algal assemblages from unexplored ecosystems.

Case of a floating right atrial thrombus successfully treated with fibrinolysis

Mobile right atrial thrombi are at high risk of causing massive pulmonary embolism and are a medical emergency. This type of thrombus is identified in about 4-18% of pulmonary embolism cases. The presence of a free-floating embolic mass in right atrial or ventricle is often mortal: the death rate can reach 27%. Although surgery is commonly indicated, fibrinolysis is a therapeutic alternative. Here, a 58-year-old man presented to the emergency department for acute dyspnea associated with a painful right leg. Initial exams showed a shunt effect on blood gases with increased brain natriuretic peptide. Transthoracic echography (TTE) found a free-floating thrombus in the right atrium with signs of pulmonary hypertension and right ventricular dysfunction. Bilateral pulmonary embolism was confirmed by computed tomography angiography. Because there were signs of acute cor pulmonale and no contraindications, treatment with systemic fibrinolysis was decided. The treatment was delivered in intensive care unit and a cardiac surgical team was available. Subsequent clinical improvement was observed. TTE follow up at 12 hours revealed complete thrombus dissolution. There were no complications, in particular no hemorrhage. The patient was discharged after eleven days. At 6 months of follow-up, outcomes with oral anticoagulation therapy were satisfactory. Scintigraphy found good symmetrical perfusion of both lungs with stackable ventilation. TTE at 1 year showed preserved left and right ventricular function with no sign of pulmonary arterial hypertension and no thrombus recurrence. Systemic fibrinolysis appears to be a good alternative to surgery in this case.

Bs → Kℓv form factors with 2+1 flavors

Using the MILC 2+1 flavor asqtad quark action ensembles, we are calculating the form factors f0 and f+ for the semileptonic Bs → Kℓv decay. A total of six ensembles with lattice spacing from ≈ 0.12 to 0.06 fm are being used. At the coarsest and finest lattice spacings, the light quark mass m’l is one-tenth the strange quark mass m’s. At the intermediate lattice spacing, the ratio m’l/m’s ranges from 0.05 to 0.2. The valence b quark is treated using the Sheikholeslami-Wohlert Wilson-clover action with the Fermilab interpretation. The other valence quarks use the asqtad action. When combined with (future) measurements from the LHCb and Belle II experiments, these calculations will provide an alternate determination of the CKM matrix element |Vub|.

Semileptonic B-meson decays to light pseudoscalar mesons on the HISQ ensembles

We report the status of an ongoing lattice-QCD calculation of form factors for exclusive semileptonic decays of B mesons with both charged currents (B → πlv, Bs → Klv) and neutral currents (B → πl+l-, B → Kl+l-). The results are important for constraining or revealing physics beyond the Standard Model. This work uses MILC’s (2+1 + 1)-flavor ensembles with the HISQ action for the sea and light valence quarks and the clover action in the Fermilab interpretation for the b quark. Simulations are carried out at three lattice spacings down to 0.088 fm, with both physical and unphysical sea-quark masses. We present preliminary results for correlation-function fits.

Function-structure connectivity in patients with severe brain injury as measured by MRI-DWI and FDG-PET

A vast body of literature exists showing functional and structural dysfunction within the brains of patients with disorders of consciousness. However, the function (fluorodeoxyglucose FDG-PET metabolism)-structure (MRI-diffusion-weighted images; DWI) relationship and how it is affected in severely brain injured patients remains ill-defined. FDG-PET and MRI-DWI in 25 severely brain injured patients (19 Disorders of Consciousness of which 7 unresponsive wakefulness syndrome, 12 minimally conscious; 6 emergence from minimally conscious state) and 25 healthy control subjects were acquired here. Default mode network (DMN) function-structure connectivity was assessed by fractional anisotropy (FA) and metabolic standardized uptake value (SUV). As expected, a profound decline in regional metabolism and white matter integrity was found in patients as compared with healthy subjects. Furthermore, a function-structure relationship was present in brain-damaged patients between functional metabolism of inferior-parietal, precuneus, and frontal regions and structural integrity of the frontal-inferiorparietal, precuneus-inferiorparietal, thalamo-inferioparietal, and thalamofrontal tracts. When focusing on patients, a stronger relationship between structural integrity of thalamo-inferiorparietal tracts and thalamic metabolism in patients who have emerged from the minimally conscious state as compared with patients with disorders of consciousness was found. The latter finding was in line with the mesocircuit hypothesis for the emergence of consciousness. The findings showed a positive function-structure relationship within most regions of the DMN. Hum Brain Mapp 37:3707-3720, 2016. © 2016 Wiley Periodicals, Inc.

Nrf2-dependent persistent oxidative stress results in stress-induced vulnerability to depression

Stressful life events produce a state of vulnerability to depression in some individuals. The mechanisms that contribute to vulnerability to depression remain poorly understood. A rat model of intense stress (social defeat (SD), first hit) produced vulnerability to depression in 40% of animals. Only vulnerable animals developed a depression-like phenotype after a second stressful hit (chronic mild stress). We found that this vulnerability to depression resulted from a persistent state of oxidative stress, which was reversed by treatment with antioxidants. This persistent state of oxidative stress was due to low brain-derived neurotrophic factor (BDNF) levels, which characterized the vulnerable animals. We found that BDNF constitutively controlled the nuclear translocation of the master redox-sensitive transcription factor Nrf2, which activates antioxidant defenses. Low BDNF levels in vulnerable animals prevented Nrf2 translocation and consequently prevented the activation of detoxifying/antioxidant enzymes, ultimately resulting in the generation of sustained oxidative stress. Activating Nrf2 translocation restored redox homeostasis and reversed vulnerability to depression. This mechanism was confirmed in Nrf2-null mice. The mice displayed high levels of oxidative stress and were inherently vulnerable to depression, but this phenotype was reversed by treatment with antioxidants. Our data reveal a novel role for BDNF in controlling redox homeostasis and provide a mechanistic explanation for post-stress vulnerability to depression while suggesting ways to reverse it. Because numerous enzymatic reactions produce reactive oxygen species that must then be cleared, the finding that BDNF controls endogenous redox homeostasis opens new avenues for investigation.

Fermi surface map of large-scale single-orientation graphene on SiO2

Large scale tetraoctylammonium-assisted electrochemical transfer of graphene grown on single-crystalline Ir(1 1 1) films by chemical vapour deposition is reported. The transferred samples are characterized in air with optical microscopy, Raman spectroscopy and four point transport measurements, providing the sheet resistance and the Hall carrier concentration. In vacuum we apply low energy electron diffraction and photoelectron spectroscopy that indicate transferred large-scale single orientation graphene. Angular resolved photoemission reveals a Fermi surface and a Dirac point energy which are consistent with charge neutral graphene.

Topological cell clustering in the ATLAS calorimeters and its performance in LHC Run 1

The reconstruction of the signal from hadrons and jets emerging from the proton-proton collisions at the Large Hadron Collider (LHC) and entering the ATLAS calorimeters is based on a three-dimensional topological clustering of individual calorimeter cell signals. The cluster formation follows cell signal-significance patterns generated by electromagnetic and hadronic showers. In this, the clustering algorithm implicitly performs a topological noise suppression by removing cells with insignificant signals which are not in close proximity to cells with significant signals. The resulting topological cell clusters have shape and location information, which is exploited to apply a local energy calibration and corrections depending on the nature of the cluster. Topological cell clustering is established as a well-performing calorimeter signal definition for jet and missing transverse momentum reconstruction in ATLAS.

West Nile virus infection in horses, Indian ocean

The circulation of West Nile virus (WNV) in horses was investigated in the Southwest Indian ocean. In 2010, blood samples were collected from a total of 303 horses originating from Madagascar, Mauritius, Reunion and the Seychelles and tested for WNV-specific antibodies. An overall seroprevalence of 27.39% was detected in the Indian Ocean with the highest WNV antibody prevalence of 46.22% (95% CI: [37.4-55.2%]) in Madagascar. The age and origin of the horses were found to be associated with the WNV infection risk. This paper presents the first seroprevalence study investigating WN fever in horses in the Southwest Indian Ocean area and indicates a potential risk of infection for humans and animals. In order to gain a better understanding of WN transmission cycles, WNV surveillance needs to be implemented in each of the countries.