[Bilateral central serous chorioretinopathy post-COVID-19]. / Choriorétinopathie séreuse centrale bilatérale post-COVID-19.

Coronavirus disease (COVID-19) can result in many ocular manifestations. We report a rare case of bilateral central serous chorioretinopathy post-infection with COVID-19 in a 38-year-old woman who presented with bilateral blurred vision 1 month after infection with COVID-19. She reported fever, cough, and shortness of breath and was COVID-PCR positive. During her 10-day hospital stay, she received oxygen, antibiotics, heparin and corticosteroids intravenously and then orally. After her recovery from COVID-19, the patient developed progressive visual loss in both eyes: her corrected visual acuity was 3/10 in both eyes, the anterior segment was normal, and the vitreous was clear. Fundus examination, optical coherence tomography and fluorescein angiography showed bilateral serous retinal detachments. Her course was characterized by improvement in visual acuity and regression of the retinal detachments. Central serous chorioretinopathy can occur after COVID-19 infection due to the administration of corticosteroids; thus, ophthalmologic examination is essential to detect ocular involvement as early as possible.

Ultrasonic assisted cross-flow ultrafiltration of starch and cellulose nanocrystals suspensions: characterization at multi-scales.

This study investigates for the first time the behaviors of starch and cellulose nanocrystals (SNC and CNC) suspensions which are simultaneously subjected to pressure, shear flow and ultrasound (US) during cross-flow ultrafiltration. This multi-forces process was characterized from macro-scales to nano-scales, with a custom designed "SAXS Cross-Flow US-coupled Filtration Cell". In addition, rheological behaviors of SNC samples at different concentrations/temperatures have been investigated. In both cases (ultrafiltration of SNC and CNC suspensions), better performances were observed with US. The in-situ SAXS measurements revealed that for SNC suspensions, no structure change occurred at the length scales range from 10 to 60nm in this multi-forces process, while CNC particles exhibited an ordered arrangement within the concentrated layer during the same process. SNC particles accumulated on the membrane surface forming a "fragile" concentrated layer which was removed very quickly by subsequent applied US. In contrary, the CNC particles accumulation was very severe, the additional ultrasonic force led to a disruption but not a totally removal of the CNC concentrated layer.

A polymorphism in FAS gene promoter correlated with circulating soluble FAS levels.

The -670FAS (A/G) polymorphism and elevated concentrations of the soluble form of FAS (sFAS) have been associated with neoplasic and autoimmune diseases. This polymorphism in the Fas promoter gene could modulate the transcription of Fas expression and therefore, contribute to these pathologies. The in vivo functional significance of the FAS polymorphism was investigated by assessing the correlation between FAS genotypes and the serum-circulating FAS (sFAS) levels. We determined the FAS polymorphism distributions by restriction fragment-length polymorphism-polymerase chain reaction in 170 normal subjects. We used enzyme-linked immunosorbent assay to evaluate the sFAS levels in 44 of these individuals. Assessment of the concentration of sFAS indicated that the level of sFAS in subjects carrying the FAS-A/A genotype was significantly higher than that of those carrying the G/G genotype (3.90 ng mL(-1) vs. 3.12 ng mL(-1), P = 0.035). Our results demonstrated that FAS promoter polymorphism was significantly associated with the level of soluble FAS production in normal subjects.

[Anatomic characteristics of the mastoid in children. Pneumatization of the subfacial region]. / Particularités anatomiques de la mastoïde de l'enfant. Pneumatisation de la région sous-faciale.

Three specific features of the mastoid in the pediatric population appeared to us to be important in view of our per-operative findings on mastoidectomy for chronic suppurative otitis, cholesteatoma or middle ear effusion with chronic persistent mastoiditis in the older child. These included the position of the facial nerve, the superficial nature of its third part being well known, but also the existence of the Körner septum and especially the pneumatization of the sub-facial region which explains the similarity between certain infectious lesions of the retro-tympanic structures and infectious lesions of the anterior portion of the mastoid process. An experimental study of staining of preserved petrous bones in the adult enabled the sub-facial permeability of the mastoid to be demonstrated in certain cases. Awareness of these small details should help to avoid per or post-operative complications in surgery for chronic otitis media in children.