Ankle: surface coil MR imaging at 1.5 T

High-field surface coil magnetic resonance (MR) images were obtained of 12 ankles: two from healthy volunteers, seven from patients, and three from fresh cadavers. The cadaver ankles were sectioned in the coronal, sagittal, and axial planes for direct comparison with the MR images. Plain film confirmation of pathologic conditions was obtained in all patients, and five underwent arthroscopy or surgery, or both. MR imaging provided excellent delineation of ligaments and cartilaginous structures in all cases.     

Platelet transfusion from donors mismatched for crossreactive HLA antigens

Increments in platelet counts following the transfusion of platelets mismatched for crossreactive antigens were evaluated in 67 patients with broad alloimmunization to HLA antigens. The corrected increments following 100 HLA, A-matched and B1U- or B2U-matched transfusions were compared with the increments following 307 B1X- or B2X-matched transfusions. HLA-A3 platelets were tolerated poorly by A1 and A11 recipients, as were A1 and A11 by A3 recipients, B17 and BW21 by recipients in the B7 crossreactive group, B5 by B15 and B17 recipients, and B27 by recipients in the B5 crossreactive group. B12 and BW21, and B8 and B14 platelets were not tolerated bidirectionally. Antigens associated with good increments included A28 in A2 recipients, B18 and BW16 (C match) in recipients in the B5 crossreactive group, B5 in B18 recipients, BW22 and B7 in recipients in the B7 crossreactive group. A1 and A11 were transfused successfully bidirectionally. These observations suggest that some private antigens within crossreactive groups are more immunogenic than others and support the observation of others than B17 and BW21 are not in the B5 crossreactive group.     

Microcytosis, iron deficiency and thalassaemia in a multi-ethnic community: a pilot study

The high prevalence of microcytosis (defined here as mean cell haemoglobin<27 pg) with no other abnormality is a principal cause of confusion in screening for haemoglobin disorders. Here we report the results of a small pilot study aiming to resolve this confusion by routinely proceeding to plasma ferritin and HPLC assay, using the original sequestrene blood sample, when microcytosis is detected. Participants comprised a random sample of 1,302 people referred for a full blood count by their General Practitioner (GP) to the laboratory of a North London district general hospital serving a multi-ethnic inner-city population. Ethnicity was established by questionnaire. In North Europeans, microcytosis was present in 3% of males (half were iron-deficient) and 11% of females (most were iron-deficient). Among ethnic minorities, microcytosis was present in 35% of males (one tenth were iron-deficient), and 45% of females (less than half were iron-deficient): an exclusion diagnosis of "probable alpha thalassaemia" could be made in the remainder. We conclude that when microcytosis is present, routine further analysis of the original sequestrene sample by plasma ferritin assay and haemoglobinopathy screening could lead to a more efficient and cost-effective laboratory service for primary care and maternity services.     

Hypergammaglobulinemia can be associated with a positive direct antiglobulin test, a nonreactive eluate, and no evidence of hemolysis

To determine the cause of a positive direct antiglobulin test (DAT), blood banks routinely perform serologic tests on eluates prepared from DAT-positive red cells. Negative eluates traditionally have been suspected to be associated with drug reactions. This report confirms that the most frequent cause of a positive DAT and a nonreactive eluate is hypergammaglobulinemia. The results of 74 patient samples with positive DATs were analyzed retrospectively. Eluates prepared from the red cells of 54 patients (72.9%) reacted; eluates from 20 patients (27.1%) did not react. This latter group had identical serologic and clinical findings, suggesting that they made up a homogeneous group. In particular, the patients had a positive DAT, a negative indirect antiglobulin test, and a negative eluate; an increased serum concentration of IgG; and no evidence of hemolysis. In a subsequent study, DATs were performed prospectively on red cells from 44 consecutive patients with elevated serum IgG levels. The serum IgG concentration was highest in the three patients whose red cells had a positive DAT. The DAT also became positive in two patients treated with high-dose intravenous gammaglobulin (IV IgG). These studies indicate that a negative eluate from red cells with a positive DAT, a common serologic finding, is often caused by hypergammaglobulinemia. The authors postulate that IgG binds nonspecifically to the red cells because of the hypergammaglobulinemia.     

Longitudinal development in the preterm thalamus and posterior white matter: MRI correlations between diffusion weighted imaging and T2 relaxometry

Infants born prematurely are at increased risk of adverse neurodevelopmental outcome. The measurement of white matter tissue composition and structure can help predict functional performance. Specifically, measurements of myelination and indicators of myelination status in the preterm brain could be predictive of later neurological outcome. Quantitative imaging of myelin could thus serve to develop biomarkers for prognosis or therapeutic intervention; however, accurate estimation of myelin content is difficult. This work combines diffusion MRI and multi‐component T2 relaxation measurements in a group of 37 infants born very preterm and scanned between 27 and 58 weeks equivalent gestational age. Seven infants have longitudinal data at two time points that we analyze in detail. Our aim is to show that measurement of the myelin water fraction is achievable using widely available pulse sequences and state‐of‐the‐art algorithmic modeling of the MR imaging procedure and that a multi‐component fitting routine to multi‐shell diffusion weighted data can show differences in neurite density and local spatial arrangement in grey and white matter. Inference on the myelin water fraction allows us to demonstrate that the change in diffusion properties of the preterm thalamus is not solely due to myelination (that increase in myelin content accounts for about a third of the observed changes) whilst the decrease in the posterior white matter T2 has no significant component that is due to myelin water content. This work applies multi‐modal advanced quantitative neuroimaging to investigate changing tissue properties in the longitudinal setting. Hum Brain Mapp 37:2479–2492, 2016. © The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. .     

聚乙二醇在猪组织工程瓣膜制备中的应用

目的:观察聚乙二醇法在组织工程瓣膜准备中的应用价值,比较聚乙二醇去细胞前后组织工程瓣膜的物理特性。方法:实验于2005-10/2006-03在华中科技大学同济医学院基础医学院生物化学系实验室完成。①实验分组:取猪10只,由于猪主动脉瓣为三叶瓣结构,共取得瓣叶组织30个,麻醉后宰杀取其心脏动脉瓣膜,分为去细胞组和对照组,每组各15个。②实验方法:去细胞组用聚乙二醇和DNase I处理;瓣叶组织放入1kg/L聚乙二醇,室温下浸泡30～45min,振荡器加以振荡;含抗生素磷酸盐缓冲液浸泡24h,反复3次洗脱;以5×104U/L DNase I液浸泡处理1h;对照组仅以含抗生素磷酸盐缓冲液浸泡24h,反复3次洗脱。③实验评估:苏木精-伊红染色、扫描电镜观察去细胞情况,吸光度(A)值,计算去细胞率(%)=(对照组A值-去细胞组A值)/对照组A值×100%。猪去细胞瓣膜条置于力学测试仪测定最大负荷、最大应力、最大应变和弹性模量。结果:纳入猪10只,均进入结果分析。①去细胞组织形态学观察:去细胞组猪瓣膜组织中看不到细胞成分,且细胞外基质结构保存完整,胶原纤维排列整齐,无明显断裂,仍呈波浪状平行排列,结构紧凑,弹性纤维结构清晰,组织无明显水肿。②DNA含量分析:聚乙二醇处理后去细胞百分率为95.32%。③生物力学检测:与对照组比较,去细胞组瓣膜组织最大负荷[(12.586±1.693),(10.242±1.435)N,P>0.05]、最大应力[(2.346±0.342),(1.877±0.572)N/mm,P>0.05]、弹性模量(15.152±1.579,14.549±0.678,P>0.05)、最大应变[(31.685±7.533),(28.118±6.045)mm/N,>0.05]等均无显著差异。P结论:聚乙二醇法去除细胞完全,细胞外基质保存完整,对组织机械性能无明显影响,适于构建组织工程瓣膜。     

A guide to managing the pain of treatment-related oral mucositis

Oral mucositis is a common complication of chemotherapy and/or radiotherapy and can be a significant problem for patients undergoing cancer treatment or bone marrow transplantation. Frequently, there is a major adverse impact on quality of life, particularly with pain and interference with oral function. In patients who are immunocompromised or debilitated, this complication can become life threatening. Currently, there is no single intervention that completely prevents or treats oral mucositis. The object of this article is to provide an overview for the nurse of the evidence for several options that may be of value in managing the pain which is often associated with this condition.