Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
Sickle cell anemia (SS) is characterized by a reduced cerebral microvascular oxygen saturation (cerebral TOI), which is not associated with hemoglobin concentration. Cerebral TOI has never been studied in sickle cell-hemoglobin C disease (SC). We focused on the relationships between hemorheological alterations and cerebral TOI in sickle cell patients with no cerebral vasculopathy and on the usefulness of TOI variability to assess the cerebral vasomotion activity. The blood rheological profile, the level of cerebral TOI (spatial resolved spectroscopy) and the cerebral TOI variability, which reflects vasomotion activity, were compared between 20 healthy subjects (AA), 21 SC patients, and 21 SS patients. Cerebral TOI exhibited the following order: AA > SC > SS. The low cerebral TOI in SS patients was related to red blood cell aggregation and deformability properties. The cerebral TOI variability of SS and SC patients was increased above healthy values and vasomotion activity was negatively associated with the reduced cerebral TOI in SS patients. We demonstrated that (1) blood rheology could be involved in the reduced cerebral TOI in SS patients but not in SC patients; (2) vasomotion activity is increased in SS and SC patients to compensate for the reduced cerebral TOI.
ISSN: 0361-8609

inserm-00838966
http://www.hal.inserm.fr/inserm-00838966
http://www.hal.inserm.fr/inserm-00838966/document
http://www.hal.inserm.fr/inserm-00838966/file/2013_Waltz_American_Journalsur Hematology.pdf
DOI : 10.1002/ajh.23318

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
Varicella zoster virus (VZV) is a leading cause of acute viral encephalitis but little is known about its clinical, biological and imaging features. Furthermore, the most favourable treatment regimen has not been determined. We studied a prospective cohort of 20 HIV-negative patients presenting with acute VZV encephalitis caused by primary infection or reactivation. VZV was identified in 16 of 20 cases by PCR detection of the DNA in the cerebrospinal fluid. The four remaining cases occurred during or soon after a VZV rash. The median age of the 17 adults was 76 (19-86) years; the three other patients were children (0.5-5 years). Three patients were immunocompromised. Nine adult patients presented with a rash. Eighteen patients presented with fever and an acute encephalitic syndrome: diffuse brain dysfunction, focal neurological signs, seizures and cranial nerve palsies. Three patients presented with either ventricular or subdural haemorrhage, one with myelitis, and one with asymptomatic stenosis of the middle cerebral artery. The imaging was either normal or revealed non-specific abnormalities such as cortical atrophy but no evidence of stroke. All patients were given acyclovir at various dosages and durations but the case fatality rate remained high (15%) and sequelae were frequently observed either at discharge or at follow-up 3 years later.
ISSN: 1198-743X

hal-00875232
https://hal.archives-ouvertes.fr/hal-00875232
PUBMED : 22085160
DOI : 10.1111/j.1469-0691.2011.03705.x

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
Oxidative stress and haemolysis-associated nitric oxide (NO) depletion plays a crucial role in the development of vasculopathy in sickle cell anaemia (SS). However it remains unknown whether oxidative stress and haemolysis levels influence vascular function in patients with sickle haemoglobin C disease (SC). Microvascular response to heat (using Laser Doppler flowmetry on finger), oxidative stress biomarkers, NO metabolites, endothelin-1 and haematological parameters were compared between patients with SS and SC. Vascular function, oxidative and nitrosative markers were also measured in healthy (AA) children. SS and SC had increased plasma advanced oxidation protein products (AOPP), malondialdehyde, plasma antioxidant activities and NO end products, compared to AA. SC had lower catalase activity compared to AA and SS. Haemolytic rate, glutathione peroxidase and nitrotyrosine concentrations were significantly increased in children with SS compared to SC and AA. SS and SC had impaired microvascular reactivity compared to AA. In SS, the plateau phase of the response to local thermal heating was negatively associated with nitrotyrosine and AOPP. No association between vascular function parameters and oxidative stress markers was observed in SC. Mild haemolysis in SC, compared to SS, may limit oxidative and nitrosative stress and could explain the better preserved microvascular function in this group.
ISSN: 0007-1048

hal-01668314
https://hal.univ-antilles.fr/hal-01668314
DOI : 10.1111/bjh.14693