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951.
Michal Krawczyk Lillian J. Barra Luciano A. Sposato Jennifer L. Mandzia 《Autoimmunity reviews》2021,20(1):102714
BackgroundPrimary Central Nervous System Vasculitis (PCNSV) remains a diagnostic challenge due to its variable and non-specific clinical manifestations. In part, the clinical heterogeneity of PCNSV may be a consequence of the modalities used for diagnosis; accordingly, there may be different subtypes of PCNSV based on whether the diagnosis was attained by biopsy or cerebral angiography.ObjectiveTo examine the frequency of symptoms, laboratory, and radiological features associated with PCNSV, and to identify distinct clinical features between biopsy and angiography defined PCNSV.MethodsWe conducted a systematic review of articles published in the English language from 1991 to 2019 that met all diagnostic criteria of PCNSV.ResultsWe identified 55 studies, reporting on 907 PCNSV cases. Median age was 45 (IQR 50–36), and 53% were women. Biopsy compared to angiography defined PCNSV had a higher percentage of cognitive impairment, and seizures on initial presentation, and were more likely to have a subacute or progressive onset, abnormal CSF profile, small vessel involvement on angiography, and tumor-like lesions and gadolinium enhancement on MRI. Angiography defined PCNSV were more likely to have an acute onset, focal weakness and visual impairment on initial presentation, medium vessel involvement on angiography, and infarcts on MRI. Brain biopsy was diagnostic of PCNSV in 71% of cases, and demonstrated an alternative diagnosis in 37% of cases, the most common being infection (19%) and lymphoproliferative disease (18%).ConclusionsThis study provides further evidence that there are distinct clinical features between biopsy and angiography defined PCNSV, which may aid in selecting patients for appropriate invasive tests. 相似文献
952.
Sandra C. Becerra Barbara A. Christy Maryanne C. Herzig James A. Bynum Daniel N. Darlington 《Transfusion》2023,63(Z3):S138-S145
Background
Exposure to radiation through battlefield use of nuclear weapons, terrorist attacks or accidents at nuclear power plants is a current concern for the military. Beyond the risk of exposure to personnel is the intentional or accidental irradiation of our blood banking supply system. It is unknown how large doses of ionizing radiation affect storage of blood and blood products, including platelets. The major function of platelets is clot formation which includes aggregation, shape change, vesicle release, and fibrinogen attachment; these tasks require a significant amount of energy. Here, we determine whether the ionizing radiation effects the energy metabolome of platelets in storage.Study Design and Methods
Fresh whole blood from healthy volunteers was subjected to 0, 25, or 75Gy of X-irradiation, and stored at 4°C. Platelets were isolated from stored WB at 0, 1, 7, 14, and 21 days of storage. Krebs cycle intermediates, nicotinamide adenine dinucleotides, and the tri-, di, and mono- phosphorylated versions of adenosine and guanosine were extracted and measured by tandem mass spectroscopy.Results
Irradiation at either 25Gy or 75Gy had no significant effect on the amount of any metabolite measured compared to control (0Gy). However, there was a significant fall over time in storage for most of the metabolites measured.Discussion
These data show that irradiation at high doses has no effect on the concentration of the energy metabolome of platelets derived from whole blood stored in 4°C for up to 21 days and suggests that platelets can maintain their metabolome even after radiation exposure. 相似文献953.