ABSTRACT
【Objective】 To analyze the changes of activation, function and metabolism of apheresis platelets during storage. 【Methods】 Five groups of apheresis platelets(n=10per group), stored up to 5 days at 20~24℃ with agitation, were sampledat day0(4 hours within collection), 1, 2, 3 and 4, respectively to assess the activation indexes as PAC-1 and CD62P and platelet function was evaluated by thromboelastogram.The platelet counts and related parameters were determined, and the biochemical indexes such as pH, glucose, lactic acid and lactate dehydrogenase reflecting metabolism were measured and statistically analyzed. 【Results】 The CD62P (%) and PAC-1 (%) of apheresis platelets with different storage duration showed significant differences(P0.05). Significant differences were notable in platelet biochemical indexesby groups using variance analysis(P<0.05). The pH value and glucose were the lowest in platelets with 4-day storage, while lactic acid and lactate dehydrogenase were the highest. 【Conclusion】 The storagelesion of apheresis platelets occurs as the activation, function and metabolism of platelets developed as the storage prolonged.
ABSTRACT
Objective:To compare MRI findings of uveal melanomas and other intraocular masses in adults and to evaluate the optimal MRI features for the differential diagnosis.Methods:The MRI data of 254 patients with intraocular masses confirmed by histopathologic or clinical follow-up results from March 2005 to December 2015 in Beijing Tongren Hospital, Capital Medical University was analyzed retrospectively. A total of 128 patients with uveal melanoma and 126 patients with other intraocular masses were enrolled. MRI findings of the masses including the location, shape, margin, signal intensity on T 1WI and T 2WI compared to the gray matter and vitreous body, homogeneity and degree of enhancement of the mass, secondary retinal detachment, height, and ratio of basal diameter to height were compared between uveal melanoma and other intraocular masses by χ 2 test or independent t test. The logistic regression analysis was performed to identify the most discriminating MRI features. The diagnostic performance of different predictive models was analyzed by receiver operating characteristic (ROC) curve. The model of multiple parameters was established by logistic analysis, and the diagnostic efficacy was evaluated. Results:The location, shape, margin, signal intensity on T 1WI and T 2WI compared to the gray matter and vitreous body, homogeneity and degree of enhancement of the mass, secondary retinal detachment, height and ratio of basal diameter to height were significantly different between the uveal melanoma and other intraocular masses (all P<0.05). The results of logistic regression analysis showed that the signal intensity on T 1WI and T 2WI compared to the gray matter, height, shape, location, degree of enhancement of the mass, and secondary retinal detachment were associated with higher likelihood of uveal melanoma. The mass with hypointense on T 2WI (compared with gray matter) was the best MRI feature in the differential diagnosis of uveal melanoma and other intraocular masses (odds ratio 12.237), with the accuracy of 86.2%. The diagnostic accuracy of low signal on T 2WI and high signal on T 1WI (compared with gray matter) was significantly higher than those of vitreous (Delong test, P<0.001). The sensitivity, specificity and accuracy of the combination of height, degree of enhancement, T 1WI and T 2WI signal compared to the gray matter were 90.6%, 92.1% and 96.1%, respectively. The diagnostic performance of combination features was higher than that of each single sign ( P<0.001). Conclusion:MRI features including the signal intensity on T 1WI and T 2WI compared to the gray matter, height, shape, degree of enhancement of the mass, and secondary retinal detachment are helpful in the differential diagnosis between uveal melanoma and other intraocular masses. In addition, the gray matter as the reference is superior to the vitreous body in the evaluation of the signal intensity of intraocular masses.
ABSTRACT
Objective To investigate the clinical and radiologic features of posterior reversible encephalopathy syndrome (PRES) associated with preeclampsia-eclampsia.Methods Twenty-one cases of PRES associated with preeclampsia-eclampsia were retrospectively studied on some aspects of clinical and radiologic features.Results The most common clinical presentations were seizures( 18 cases ),headache (16 cases),altered mentation (15 cases) and vision change (12 cases). Vasogenic edema lesions distributed in the parietal or occipital lobe (20 cases),the frontal lobes (14 cases),temporal lobes ( 11 cases), and basal ganglia (11 cases). The splenium involvement occurred in 4 cases,cerebellar hemispheres and brain stem involvement was prcscnted in 3 cases and 1 case separately. Three major patterns of PRES included dominant parietal-occipital (7 cases),the holohemispheric watershed (7 cases),and superior frontal sulcal (6 cases).Partial and asymmetric expression of PRES only occurred in 1 case.Conclusions The clinical features of PRES associated with preeclampsia-eclampsia are typical.Except the parietal or occipital lobe,involvement of the frontal lobe,temporal lobe and basal ganglia is common,followed by the occasional presence of the splenium,cerebellar hemispheres and brain stem.Three primary PRES patterns are noted,occasional with partial and asymmetric expression of PRES. Awareness of these typical and variable characteristics is important to recognize the PRES ncurotoxicity morc accurately when PRES present.