Abnormal brain function in photophobic patients with dry eye disease: An fMRI study.

BACKGROUND AND OBJECTIVES: Photophobia, a frequent and disabling symptom observed in various neurological conditions and eye diseases, is thought to involve maladaptive brain functioning. We assessed this hypothesis, using functional magnetic resonance imaging (fMRI) in photophobic patients with minimal-to-severe dry eye disease (DED), as compared to healthy controls. METHODS: This prospective, monocentric, comparative, cohort study included eleven photophobic DED patients compared to eight controls. Photophobic patients had a complete evaluation of DED to exclude any other cause of photophobia. All participants were scanned with fMRI under intermittent light stimulation with a LED lamp (27s. ON, 27 s. OFF), and cerebral activations were studied with univariate contrasts between the ON and OFF conditions, and with functional connectivity methods. RESULTS: Firstly, stimulation activated the occipital cortex more strongly in patients than in controls. Moreover, stimulation deactivated the superior temporal cortex in patients less than in controls. Secondly, functional connectivity analysis showed that light stimulation induced lesser decoupling between the occipital cortex and the salience and visual networks in patients than in controls. DISCUSSION: The current data shows that DED patients with photophobia have maladaptive brain anomalies. There is hyperactivity in the cortical visual system, associated with abnormal functional interactions, both within the visual cortex, and between visual areas and salience control mechanisms. Such anomalies show similarities with other conditions such as tinnitus, hyperacusis, and neuropathic pain. Those findings support novel neurally oriented methods for the care of patients with photophobia.

Financial fallout from the COVID-19 pandemic:Report from a high-volume academic neurosurgery.

BACKGROUND: The global healthcare system has been overwhelmed by the Coronavirus disease-2019 (COVID-19). In order to mitigate the risk of spread of the virus, most elective surgical procedures have been cancelled especially during the lockdown periods. The purpose of this study was to assess the financial impact of the COVID outbreak due to the supposed reduced workload from our neurosurgery department in 2020. METHODS: Number of neurosurgical procedures (NSP) within the Department of Neurosurgery and their associated estimated income were retrospectively reviewed globally and month wise from administrative records of billing in 2020 and 2019 based on the Diagnosis related group (DRG) and severity of illness (4 levels). RESULTS: Overall, 824 and 818 inpatient surgical procedures were performed in 2019 and 2020 respectively. The total estimate revenue generated from inpatient surgeries was moderately decreased (3%): 9 498 226.41 euros in 2020 versus 9 817 361.65 euros in 2019 without significant difference across DRG (P=0.96) and severity of illness. CONCLUSIONS: Our data suggests a moderate negative impact of the COVID-19 pandemic had on neurosurgical and financial activity. However, a more in-depth medico-economic analysis need to be performed to assess the real financial impact.

Epidemiological profile of eumycetomas in Rabat, Morocco, over 40 years.

Eumycetomas are chronic subcutaneous pseudo-tumoral infections, endemic in arid tropical areas, which are caused by exogenous fungi that produce grains in vivo. The objective of our work is to establish their epidemiological, clinical and mycological profile in our Moroccan context. Therefore, we conducted a retrospective study, extending from 1975 to 2019, compiling all cases of eumycetomas that were diagnosed in the parasitology-mycology laboratory of the Ibn Sina University Hospital of Rabat. The diagnosis, based on the swabbing of exudates and eventual grains or the study of biopsies, included the direct examination of 30% KOH mounts, the realization of appositions colored by May-Grünwald-Giemsa and the incubation on 3 Sabouraud media at 27° and 37°C. In 44 years, 12 cases of eumycetoma have been diagnosed, with a male to female ratio of 5:1 and a mean age of 44.8 years. The lesions, evolving from 1 to 30 years, were podal in 10 cases, popliteal and gluteal in one case each, with osteolysis in 3 patients. The collected grains were black in 9 cases, white in 2 others. Direct examination was unanimously positive, revealing entangled hyphae, whilst culture isolated Madurella sp. in 9 cases, Trichophyton rubrum, Acremonium sp. in one case each and remained sterile in the last case. The treatment was medical in 8 cases, medico-surgical in 3 others, with loss of sight of most patients.

Autoactivation of human blood coagulation factor XII on dextran derivatives of different molecular weight.

We prepared a derivative of dextran T40 (average M(r) 43,000) from which fractions of different M(r) but with equal charge density were obtained and tested for their ability to promote autoactivation of human blood coagulation factor XII. The mechanism of autoactivation appeared dependent upon the M(r) of the polymer used. Thus, with polymers of 38,000 M(r) or higher only alpha-factor XIIa was formed and the reaction could be completely described in terms of a simple second-order mechanism of autoactivation. With smaller polymer molecules beta-factor XIIa became a major reaction product and as a result of this the autoactivation kinetics did not adhere to the second-order mechanisms thus far described.

[Paraganglioma and pregnancy]. / Paragangliome et grossesse.

A paraganglioma is an extra-adrenal pheochromocytoma, rarely observed during pregnancy. Maternal prognosis depends on early diagnosis and multidisciplinary management prior to tumor resection. The tumor is localized by ultrasonography or MRI. During the post-partum, and if MRI is not available, CT is often sufficient. We report a paragangliona in a patient with intrauterine fetal demise at 27 weeks gestation diagnosed by ultrasonography and computed tomography, who underwent surgical resection.

Ion adsorption at a metallic electrode: an ab initio based simulation study.

A method for parametrizing, from first principles density functional theory calculations, a model of the interactions between the ions in an ionic liquid and a metallic (electrode) surface is described. The interaction model includes the induction of dipoles on the ions of the liquid by their mutual interaction and the interaction with the electrode surface as well as the polarization of the metal by the ionic charges and dipoles ('image' interactions). The method is used to obtain a suitable interaction model for a system consisting of a LiCl liquid electrolyte and a solid aluminium electrode. The model is then used in simulations of this system for various values of the electrical potential applied to the electrode. The evolution of the liquid structure at the electrochemical interface with applied potential is followed and the capacitance of the electrochemical interface is measured. The electrolyte is found to exhibit a potential-driven phase transition which involves the commensurate ordering of the electrolyte ions with the electrode surface; this leads to a maximum in the differential capacitance as a function of applied potential. Away from the phase transition the capacitance was found to be independent of the applied potential.