SUMMARY Tomogrephic images of cerebral blood flow (CBF) and oxygen extraction fraction (OEF) using the U O continuous inhalation technique, and positron emission tomography, were obtained from a patient with cerebral ischemia distal to an occluded left internal carotid artery. There was a focal mismatch between CBF and oxygen metabolism in the brain supplied by tbe middle cerebral artery where CBF was decreased and OEF increased ("misery-perfusion syndrome" as opposed to "luxury-perfusioa syndrome"). These abnormalities were most marked in tbe parieto-ocdpital watershed area. After left superficial temporal to middle cerebral artery anastomosis, the clinical attacks ceased and a repeat study did not demonstrate tbe prerious CBF and OEF abnormalities. This suggests that this pattern of abnormalities indicates potential liable tissue. The concept of "mlsery-perfuslon" may be of some importance In tbe patbophysiological mechanisms of hemodynamic cerebral ischemia and serve as a rational basis for rerascularization procedures.
We have developed a brief screening test aimed at identifying cognitive disorders in Parkinson's disease. The Mini-Mental Parkinson derives from the Mini-Mental State Examination of Folstein. It includes seven ordered subsections, with a total score of 32. A pilot study was conducted in 50 community-dwelling parkinsonian patients, in order to establish its metrological qualities. Comparisons were made with a neuropsychological battery including several tests widely used in the assessment of specific cognitive disorders in Parkinson's disease. The correlations between the Mini-Mental Parkinson and each component of this battery were substantial, especially for the performance subtests of the WAIS-R (r = 0.62 to 0.72), the Stroop test (r = 0.65) the 15-objects test (r = 0.64), the word fluency (r = 0.63) and the Odd Man Out test (r = 0.61). The validity of each subtest of the Mini-Mental Parkinson was adequate except for one, based on a word choice, which requires a modification in French before definitive use. The test-retest reliability was high (r = 0.84). There was a significant difference in the mean scores in cases with confusional event (22.4), even without current signs of dementia, compared with patients with no such history (27.2). In conclusion, this brief test is suitable for assessment of parkinsonian patients.
Background
Titanium dioxide (TiO2) is broadly used in common consumer goods, including as a food additive (E171 in Europe) for colouring and opacifying properties. The E171 additive contains TiO2 nanoparticles (NPs), part of them being absorbed in the intestine and accumulated in several systemic organs. Exposure to TiO2-NPs in rodents during pregnancy resulted in alteration of placental functions and a materno-foetal transfer of NPs, both with toxic effects on the foetus. However, no human data are available for pregnant women exposed to food-grade TiO2-NPs and their potential transfer to the foetus. In this study, human placentae collected at term from normal pregnancies and meconium (the first stool of newborns) from unpaired mothers/children were analysed using inductively coupled plasma mass spectrometry (ICP-MS) and scanning transmission electron microscopy (STEM) coupled to energy-dispersive X-ray (EDX) spectroscopy for their titanium (Ti) contents and for analysis of TiO2 particle deposition, respectively. Using an ex vivo placenta perfusion model, we also assessed the transplacental passage of food-grade TiO2 particles.
Results
By ICP-MS analysis, we evidenced the presence of Ti in all placentae (basal level ranging from 0.01 to 0.48 mg/kg of tissue) and in 50% of the meconium samples (0.02–1.50 mg/kg), suggesting a materno-foetal passage of Ti. STEM-EDX observation of the placental tissues confirmed the presence of TiO2-NPs in addition to iron (Fe), tin (Sn), aluminium (Al) and silicon (Si) as mixed or isolated particle deposits. TiO2 particles, as well as Si, Al, Fe and zinc (Zn) particles were also recovered in the meconium. In placenta perfusion experiments, confocal imaging and SEM-EDX analysis of foetal exudate confirmed a low transfer of food-grade TiO2 particles to the foetal side, which was barely quantifiable by ICP-MS. Diameter measurements showed that 70 to 100% of the TiO2 particles recovered in the foetal exudate were nanosized.
Conclusions
Altogether, these results show a materno-foetal transfer of TiO2 particles during pregnancy, with food-grade TiO2 as a potential source for foetal exposure to NPs. These data emphasize the need for risk assessment of chronic exposure to TiO2-NPs during pregnancy.
Four subjects aged between 29 and 60 years were examined because of axial motor impairment after hypoxic brain injury. Magnetic resonance imaging revealed circumscribed lesions of the globus pallidus in every case. The association of freezing of the gait, speech disorders, axial bradykinesia, and postural disturbances, with no rigidity or tremor and little or no distal akinesia, suggests a role of the globus pallidus in controlling axial motion.
Two men, 89 and 83 years of age, presented with predominantly axial parkinsonian signs. In both cases, magnetic resonance imaging of the brain showed numerous small foci, delineating the striatum. The lesions had the same signal as cerebral spinal fluid in both T1 and T2 sequences. Postmortem examination of the brain showed numerous lacunes due to dilatation of the perivascular spaces, frequently associated with alterations of the surrounding brain parenchyma. Typical changes of Parkinson's disease were associated in one case. Such vascular changes may produce, or modify, a parkinsonian syndrome.
IntroductionDuring the 2014 Ebola Virus Disease (EVD) epidemic, the Ebola-Tx trial evaluated the use of convalescent plasma (CP) in Guinea. The effectiveness of plasmapheresis trials depends on the recruitment of plasma donors. This paper describes what motivated or deterred EVD survivors to donate CP, providing insights for future plasmapheresis trials and epidemic preparedness.MethodsThis qualitative study, part of Ebola-Tx, researched and addressed emergent trial difficulties through interviewing, participant observation and focus group discussions. Sampling was theoretical and retroductive analysis was done in NVivo 10.ResultsWillingness or hesitance to participate in plasma donation depended on factors at the interface of pre-existing social dynamics; the impact of the disease and the consequent emergency response including the trial set-up. For volunteers, motivation to donate was mainly related to the feeling of social responsibility inspired by having survived EVD and to positive perceptions of plasmapheresis technology despite still unknown trial outcomes. Conversely, confidentiality concerns when volunteering due to stigmatization of survivors and perceived decrease in vital strength and in antibodies when donating, leading to fears of loss in protection against EVD, were main deterrents. The dynamic (dis)trust in Ebola Response Actors and in other survivors further determined willingness to participate and lead to the emergence/decline of rumours related to blood stealing and treatment effectiveness. Historic inter-ethnic relations in the health care setting further defined volunteering along socio-economic and ethnic lines. Finally, lack of follow-up and of dedicated care further impacted on motivation to volunteer.ConclusionsEbola-Tx was the first trial to solicit and evaluate blood-product donation as an experimental treatment on a large scale in Sub-Saharan Africa. An effective donation system requires directly engaging with emergent social barriers and providing an effective ethical response, including improved and transparent communication, effective follow-up after donation, assuring confidentiality and determining ethical incentives.
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