[Comparison of foetal and neonatal mortality of monochorionic monoamniotic and monochorionic biamniotic twin pregnancies]. / Comparaison de la mortalité fœtale et néonatale des grossesses gémellaires monochoriales monoamniotiques et monochoriales biamniotiques.

OBJECTIVES: To compare the mortality of monochorionic-monoamniotic (MCMA) and monochorionic-biamniotic (MCBA) twin pregnancies, from 14weeks of gestation to 28th day of life, before and after exclusion of major congenital malformations. METHODS: We conducted a retrospective cohort study in two level 3 maternity units of the Hospices civils de Lyon (France) including all patients with a monochorionic twin pregnancy between January 2013 and December 2020. We excluded TRAP sequences and conjoined twins. RESULTS: A total of 38 MCMA and 658 MCBA pregnancies were included. We showed an increase in overall mortality in the MCMA group compared to the MCBA group (31.6% versus 16.4%, P=0.03) even after exclusion of major congenital malformations (20.3% versus 9.5%, P=0.01). The main cause of mortality found in the MCMA group was the occurrence of unexpected IUGR. CONCLUSIONS: MCMA pregnancies have a higher foetal and neonatal mortality rate than MCBA pregnancies even after exclusion of congenital malformations related to the occurrence of unexpected MFIU.

Identification of a novel type of glucose dehydrogenase involved in the mineral weathering ability of Collimonas pratensis strain PMB3(1).

The exact molecular mechanisms as well as the genes involved in the mineral weathering (MW) process by bacteria remain poorly characterized. To date, a single type of glucose dehydrogenase (GDH) depending on a particular co-factor named pyrroloquinoline quinone (PQQ) is known. These enzymes allow the production of gluconic acid through the oxidation of glucose. However, it remains to be determined how bacteria missing PQQ-dependent GDH and/or the related pqq biogenesis genes weather minerals. In this study, we considered the very effective mineral weathering bacterial strain PMB3(1) of Collimonas pratensis. Genome analysis revealed that it does not possess the PQQ-based system. The use of random mutagenesis, gene complementation and functional assays allowed us to identify mutants impacted in their ability to weather mineral. Among them, three mutants were strongly altered on their acidification and biotite weathering abilities (58% to 75% of reduction compared to WT) and did not produce gluconic acid. The characterization of the genomic regions allowed noticeably to the identification of a Glucose/Methanol/Choline oxidoreductase. This region appeared very conserved among collimonads and related genera. This study represents the first demonstration of the implication of a PQQ-independent GDH in the mineral weathering process and explains how Collimonas weather minerals.

Pediatric neurolisteriosis: A diagnosis to consider even in the absence of immunodeficiency.

Neurolisteriosis is known to affect vulnerable groups, for example neonates or children with immunodeficiency. This is a key point of the current clinical guidelines regarding pediatric meningitis. We report a rare case of neurolisteriosis in an immunocompetent infant, without the typical signs of listeriosis, which led to a delay in administering the appropriate antibiotherapy. This case illustrates the clinical heterogeneity of neurolisteriosis and the relevance of appropriate polymerase chain reaction (PCR) tests when the clinical presentation differs from the current guidelines. This case also reminds us that raw or unpasteurized milk-based food products pose a risk even in immunocompetent infants or children.

Mechanisms of remembering the past and imagining the future--new data from autobiographical memory tasks in a lifespan approach.

We investigated the episodic/semantic distinction in remembering the past and imagining the future and explored cognitive mechanisms predicting events' specificity throughout the lifespan. Eighty-three 6- to 81-year-old participants, divided into 5 age groups, underwent past, present and future episodic (events' evocation) and semantic (self-descriptions) autobiographical tasks and a complementary cognitive test battery (executive functions, working and episodic memory). The main results showed age effects on episodic events' evocation indicating an inverted U function (i.e., developmental progression from 6 to 21years and aging decline). By contrast, age effects were slighter on self-descriptions while self-defining events' evocation increased with age. Furthermore, age effects on episodic events' evocation were mainly mediated by age effects on cognitive functions and personal semantics. These new findings indicate a developmental and aging episodic/semantic distinction for both remembering the past and imagining the future, and suggest that above similarities, these abilities could have a fundamentally different basis.

Endovascular treatment of ACom intracranial aneurysms. Report on series of 280 patients.

The immediate and long-term outcomes, complications, recurrences and the need for retreatment were analyzed in a series of 280 consecutive patients with anterior communicating artery aneurysms treated with the endovascular technique. From October 1992 to October 2001 280 patients with 282 anterior communicating artery aneurysms were addressed to our center. For the analysis, the population was divided into two major groups: group 1, comprising 239 (85%) patients with ruptured aneurysms and group 2 comprising of 42 (15%) patients with unruptured aneurysms. In group 1, 185 (77.4%) patients had a good initial pre-treatment Hunt and Hess grade of I-III. Aneurysm size was divided into three categories according to the larger diameter: less than 4 mm, between 4 and 10 mm and larger than 10 mm. The sizes of aneurysms in groups 1 and 2 were identical but a less favorable neck to depth ratio of 0.5 was more frequent in group 2. Endovascular treatment was finally performed in 234 patients in group 1 and 34 patients in group 2. Complete obliteration was more frequently obtained in group 2 unlike a residual neck or opacification of the sac that were more frequently seen in group 1. No peri-treatment complications were recorded in group 2. In group 1 the peri-treatment mortality and overall peri-treatment morbidity were 5.1% and 8.1% respectively. Eight patients (3.4%) in group 1 presented early post treatment rebleeding with a mortality of 88%. The mean time to follow-up was 3.09 years. In group 1, 51 (21.7%) recurrences occurred of which 14 were minor and 37 major. In group 2, eight (23.5%) recurrences occurred, five minor and three major. Two patients (0.8%) presented late rebleeding in group 1. Twenty-seven second endovascular retreatments were performed, 24 (10.2%) in group 1 and three (8.8%) in group 2, seven third endovascular retreatments and two surgical clippings in group 1 only. There was no additional morbidity related to retreatments. Endovascular treatment is an effective method for the treatment of anterior communicating artery aneurysms allowing late rebleeding prevention. Peri-treatment rebleeding warrants caution in anticoagulation management. This is a single center experience and the follow-up period is limited. Patients should be followed-up in the long-term as recurrences may occur and warrant additional treatment.

[Radiosurgery of cerebral arteriovenous malformations: a prescription algorithm]. / Radiochirurgie des malformations artérioveineuses cérébrales : élaboration d'un algorithme de prescription.

PURPOSE: To study prognostic factors of obliteration and risk factors of brain radiation necrosis in order to propose an algorithm for radiosurgery prescription for cerebral arteriovenous malformations (cAVM). MATERIAL AND METHODS: One hundred and seventy-nine patients were analysed. Radiosurgery delivered 6 or 10 MV X-rays by arc therapy in 84% of cases, or by fixed field in 16% of cases using two different micro-multileaf collimators (micro-MLC). Follow-up consisted of screening radiation necrosis by MRI every 6 months, and assessing local control by arteriography every 2 years. Obliteration was defined as at least 95% reduction of cAVM volume. Cox proportional hazard model was used to evaluate the local control and the appearance of radiation necrosis over time. RESULTS: Local control rate was 82.7% with the mean follow-up of 3.1 years (0.5-11). Significant prognostic factors were: simple nidus (RR=2.8, p<0.0001), number of embolizations before radiosurgery below 4 (RR=2.9, p<0.0001), prescribed dose to the periphery of at least 18 Gy (RR=2, p=0.0002), nidus volume below8cm(3) (RR=1.9, p=0.0002), and number of table positions below six (RR=1.4, p=0.05). Radiation necrosis rate was 11.2% with a mean time to onset of 18 months. Significant predictive factors were: fixed field versus arc therapy (according to MLC RR=9.1, p<0.0001, and RR=15.1, p=0.01), age below 30 years (RR=2.5, p=0.04), depth of cAVM greater than or equal to 7 cm (RR=7.6, p=0.008), and volume of brain tissue covered by the 12 Gy isodose (V12 Gy) of at least 11 cm(3) (RR=7.8, p=0.05). CONCLUSION: A radiosurgery prescription algorithm taking into account the prescribed dose to the periphery (> or = 18 Gy) and reduction of V12 Gy was elaborated from these data.

[A survey of the management of unruptured intracranial aneurysms as practised by French neuroradiological and neurosurgical teams]. / Prise en charge des anévrismes intracrâniens non rompus. Enquête de pratique des équipes neurochirurgicales et neuroradiologiques françaises.

BACKGROUND: The lack of consensus in the management of unruptured intracranial aneurysms (UIA) has resulted in a variety of different clinical practices. The aim of this study is to analyze these different practices. METHODS: A questionnaire concerning the management of UIA was mailed out to French neurosurgeons (NS) and neuroradiologists (NR). Eighteen responses from 17 teams of NS and 23 responses from 19 teams of NR were included in our analysis. RESULTS: In making a therapeutic decision, about three-quarters of both NR and NS take into account the age of the patient and all of our responders except one consider the aneurysm's morphology, especially its size and neck structure. Pinpointing the location of the aneurysm is an important factor for 61% of NR and 40% of NS. Information concerning the risk of aneurysm rupture and the risks of treatment is routinely given to the patient orally and, sometimes, in writing. The follow-up of UIA treated by NR usually consists of one X-ray angiography and several MR angiographic (MRA) films taken over a period of at least five years and, sometimes, for the rest of the patient's life (22%). The follow-up after surgical treatment mainly comprises X-ray angiography for a limited period of time-usually from five to ten years. The follow-up of untreated aneurysms is usually by either MRA or angioCT. For most NR, the duration of follow-up is long and, sometimes, unlimited. For NS, the duration is more difficult to pinpoint: the response was indeterminate in 28 and 33% gave no response at all. If the first screening tests negative, 44% of NS and 61% of NR propose a repeat screening. CONCLUSION: Given the differences in the management of UIA as revealed by this survey, a multidisciplinary approach that combines the various clinical practices may be the best way forward.

[Mild head trauma: complications and acousticovestibular sequelae]. / Traumatismes crâniens légers: complications et séquelles audio-vestibulaires.

Head injury with fracture of the petrous bone is frequent and directly related to the development of human activity. Head trauma is associated with nearly 75% of traffic accidents; 5% of them with petrous bone fracture. Based on a clinical case, the acute injuries and secondary acoustic or vestibular sequelae after low-energy cranio-cerebral trauma are discussed here. The subject was a victim of a low-energy head trauma with brief loss of consciousness and translabyrinthine fracture of the petrous bone. This fracture caused invalidating equilibrium disorders related to a perilymphatic fistula. These disorders persisted for 3.5 years and required several hospitalizations and three surgical procedures. The acoustic problems progressed towards cophosis and persistent and invalidating tintinus. We discuss the pathogenesis and treatment of these different sequelae of the middle ear as well as the external lesions. Among labyrinthine involvement, especially unilateral destruction, fistulization, concussion, and post concussion syndrome are especially descripted. Bony dislocations dominate middle ear sequelae. We also discuss the medicolegal problems associated with this type of pathology.

[MRI findings in a case of prolonged status epilepticus]. / Suivi iconographique d'un etat de mal epileptique prolonge.

We report the MR imaging findings in a 20 year old woman with status epilepticus of more than 3 months duration following an episode of lymphocytic meningitis. Repeated MR examinations showed progressive symmetrical cortical lesions, followed by subcortical and basal ganglia lesions which evolved to cortical laminar necrosis and hemorrhagic necrosis with eventual subcortical cerebral atrophy. This case has similarities with animal status epilepticus models. Biological investigations were all negative. This suggests that the brain lesions may be related to the prolonged status epilepticus.

Standards of Practice in Interventional Neuroradiology or Endovascular Neurosurgery. WFITN Site Conditions and Technical Operational Guidelines.

with the working group composed of: S. Bracard, J. Byrne, L. Feng, O. Flodmark, A. Goulao, M. Leonardi, M. Mawad, J. Mishra, J. Moret, M. Negoro, R. Piske, B. Richling, G. Rodesch, J. Ruscalleda, K. terBrugge, A.Valavanis.

[Neuroimaging of hereditary hemorrhagic telangiectasia]. / Neuroradiologie de la maladie de Rendu Osler.

Hereditary Hemorrhagic telangiectasia is an autosomal dominant vascular disorder with high penetrance and variable expressivity. Most cases are caused by mutations in the endoglin gene on chromosome 9 (HHT type 1) or the activin receptor-like kinase 1 gene on chromosome 12 (HHT type 2). HHT is characterized by mucocutaneous telangiectases and visceral arteriovenous malformations (AVMs). Neurological complications occur in 8 to 10% of the patients. Brain ischemia or abscess are often associated with pulmonary arteriovenous fistula. Cerebral or spinal arteriovenous malformations are frequent but have a lower risk of haemorrhage than sporadic AVMs and routine screening should not be practiced in adult patients. Routine screening should be discussed for children with a familial history of cerebral haemorrhage and/or HHT type 1.

[Risks and responsibilities in diagnostic and interventional radiology. Ethical and medicolegal considerations]. / Risques et responsabilités en radiologie diagnostique et interventionnelle. Aspects éthiques et médico-légaux.

Medical risk management has one main purpose: to ensure the safety of care. The law of March 2002 has generated a true cultural revolution. The radiologist is involved with new and difficult areas of medical liability due to technical advances, the increasing number of imaging techniques, the increasing complexity of imaging techniques, their efficiency and the need for multidisciplinary approach. Imaging recommendations requiring increasing levels of technical and clinical skills. The radiologist is liable with regards to the indications of imaging studies, and also with regards to informed consent. The prevention of medicolegal problems is achieved by competency, which must be combined to good liability insurance and ongoing vigilance supported by appropriate continuous medical education.