The PFA‐100® does not predict delta‐granule platelet storage pool deficiencies

Summary.  There are no published reports investigating the ability of the platelet function analyzer (PFA‐100^®) to detect the presence of delta‐granule platelet storage pool deficiencies (δ‐PSPD), a common mild bleeding disorder. Prior studies of the PFA‐100^® and congenital platelet disorders have been limited by small numbers of patients with a variety of disorders. We examined PFA‐100^® results in a large paediatric patient population diagnosed specifically with δ‐PSPD, and determined the relationship between PFA‐100^® and platelet electron microscopy (the gold standard for diagnosis). This study is a retrospective review of patients <19 years of age diagnosed with δ‐PSPD at Nationwide Children’s Hospital from 2008 to 2010. To examine the correlation between PFA‐100^® and average number of granules per platelet we used Spearman’s Rho as a non‐parametric measure of dependence. A total of 105 patients diagnosed with δ‐PSPD were included, of which 99 patients underwent PFA‐100^® testing. Of those tested 46% had at least one abnormal closure time, whereas 16% had abnormal results for both cartridges. We found no statistical correlation between C‐EPI closure time and average number of granules per platelet (ρ= ?0.0095, P‐value = 0.9328), nor between C‐ADP closure time and the average number of granules (ρ = 0.0315, P‐value = 0.7798). The PFA‐100^®, a widely used screening test for suspected bleeding disorders, did not correlate with presence or severity of δ‐PSPD as determined by platelet electron microscopy. When evaluating patients with suspected bleeding disorders, PFA‐100^® alone cannot be used to rule out the presence of a δ‐PSPD.     

Mitochondrial function in human brains is affected by pre‐ and post mortem factors

G. Harish, C. Venkateshappa, A. Mahadevan, N. Pruthi, M. M. S. Bharath and S. K. Shankar (2013) Neuropathology and Applied Neurobiology 39, 298–315 Mitochondrial function in human brains is affected by pre‐ and post mortem factors Aim: Mitochondrial function and the ensuing ATP synthesis are central to the functioning of the brain and contribute to neuronal physiology. Most studies on neurodegenerative diseases have highlighted that mitochondrial dysfunction is an important event contributing to pathology. However, studies on the human brain mitochondria in various neurodegenerative disorders heavily rely on post mortem samples. As post mortem tissues are influenced by pre‐ and post mortem factors, we investigated the effect of these variables on mitochondrial function. Methods: We examined whether the mitochondrial function (represented by mitochondrial enzymes and antioxidant activities) in post mortem human brains (n = 45) was affected by increased storage time (11.8–104.1 months), age of the donor (2 days to 80 years), post mortem interval (2.5–26 h), gender difference and agonal state [based on Glasgow Coma Scale: range = 3–15] in the frontal cortex, as a prototype. Results: We observed that the activities of citrate synthase, succinate dehydrogenase and mitochondrial reductase (MTT) were significantly affected only by gender difference (citrate synthase: P = 0.005; succinate dehydrogenase: P = 0.01; mitochondrial reductase: P = 0.006), being higher in females, but not by any other factor. Mitochondrial complex I activity was significantly inhibited by increasing age (r = ?0.40; P = 0.05). On the other hand, the mitochondrial antioxidant enzyme glutathione reductase decreased with severe agonal state (P = 0.003), while the activity of glutathione‐S‐transferase declined with increased storage time (P = 0.005) and severe agonal state (P = 0.02). Conclusion: Our data highlight the influence of pre‐ and post mortem factors on preservation of mitochondrial function with implications for studies on brain pathology employing stored human samples.     

The conjunctive trace

Memories serve to establish some permanence to our inner lives despite the fleeting nature of subjective experience. Most neurobiological theories of memory assume that this mental permanence reflects an underlying cellular permanence. Namely, it is assumed that the cellular changes which first occur to store a memory are perpetuated for as long as the memory is stored. But is that really the case? In an opinion piece in this issue of Hippocampus, Aryeh Routtenberg raises the provocative idea that the subjective sense of memory persistence is not in fact a result of persistence at the cellular level, rather, that “supple synapses” and multiple “evanescent networks” that are forever changing are responsible for our memories. On one level, his proposal could be construed as a radical challenge to some of our most fundamental theories of the neurobiology of memory, including Donald Hebb's proposal that memories are stored by networks that strengthen their connections to increase the likelihood of the same activity patterns being recreated at a later date. However, it could also be seen as a moderating call, a call for a greater acknowledgement of the dynamic, stochastic, and distributed nature of neural networks. In this response to Routtenberg's article, we attempt to provide a clarification of the dividing line between these two interpretations of his argument, and in doing so, we provide some overview of the empirical evidence that bears on this subject. We argue that the data that exists to date favors the more moderate interpretation: that memory storage involves a process in which activity patterns are made more likely to reoccur, but that an under‐appreciated reality is that mnemonic traces may continue to change and evolve over time. © 2013 Wiley Periodicals, Inc.     

Lysosomal storage disorders: A review of the musculoskeletal features

The lysosomal storage disorders are a collection of progressive, multisystem disorders that frequently present in childhood. Their timely diagnosis is paramount as they are becoming increasingly treatable. Musculoskeletal manifestations often occur early in the disease course, hence are useful as diagnostics clues. Non‐inflammatory joint stiffness or pain, carpal tunnel syndrome, trigger fingers, unexplained pain crises and short stature should all prompt consideration of a lysosomal storage disorder. Recurrent ENT infections, hepatosplenomegaly, recurrent hernias and visual/hearing impairment – especially when clustered together – are important extra‐skeletal features. As diagnostic and therapeutic options continue to evolve, children with lysosomal storage disorders and their families are facing more sophisticated options for screening and treatment. The aim of this article is to highlight the paediatric presentations of lysosomal storage disorders, with an emphasis on the musculoskeletal features.     

Prenatal diagnosis of Gaucher disease using next‐generation sequencing

In the prenatal diagnosis of Gaucher disease (GD), glucocerebrosidase (GBA) activity is measured with fetal cells, and gene analysis is performed when pathogenic mutations in GBA are identified in advance. Herein is described prenatal diagnosis in a family in which two children had GD. Although prior genetic information for this GD family was not obtained, next‐generation sequencing (NGS) was carried out for this family because immediate prenatal diagnosis was necessary. Three mutations were identified in this GD family. The father had one mutation in intron 3 (IVS2 + 1), the mother had two mutations in exons 3 (I[‐20]V) and 5 (M85T), and child 1 had all three of these mutations; child 3 had none of these mutations. On NGS the present fetus (child 3) was not a carrier of GD‐related mutations. NGS may facilitate early detection and treatment before disease onset.     

海藻糖低温保存血小板miRNA差异表达分析

目的 探讨海藻糖低温保存血小板过程中miRNA的变化.方法 收集3份来自相同血型无偿献血员的单采血小板,少量混匀后,平均分为2组.对照组:新鲜血小板组(22℃,100％血浆储存的新鲜血小板2h);实验组:海藻糖低温保存血小板组(10℃,70％海藻糖保存液储存5d);采用高通量测序方法对两组样品进行了Small RNA测序,进行生物信息分析,主要包括已知miRNA鉴定、miRNA差异表达分析及富集分析.结果 2组样品经Small RNA高通量测序,平均每个样品获得了11兆净读值(Clean reads),经过生物信息分析,分别获得了821个已知miRNA.通过差异表达分析,在已知的miRNA中共有460个差异表达miRNA,其中194个miRNA表达上调,266个miRNA表达下调,其中显著差异表达已知miRNA共44个,分别在钙离子通路、MAPK通路、凋亡路径、轴突导向等储存损伤相关路径中富集程度较高.相对于对照组,实验组中hsa-miR-4449、hsa-miR-1296表达显著上调(P ＜0.01,且差异倍数＞2),hsa-miR-665表达被抑制.结论 血小板经过海藻糖低温保存后的miRNA呈现出特征性表达变化,提示miRNA活动参与了低温时海藻糖对血小板储存损伤的保护作用.     

Electron microscopic findings in skin biopsies from patients with infantile osteopetrosis and neuronal storage disease

Infantile osteopetrosis with neuronal storage disease is a rare lysosomal storage disorder. It is an autosomal recessive disease that is associated with mutations in the OSTM1 and chloride channel ClCN-7genes. So far mutations in the OSTM1 gene have been identified in only 8 patients. To date, the clinical and morphological features of nine patients with infantile osteopetrosis with neuronal storage have been reported, but no ultrastructural findings of skin have been described in these patients. Skin biopsy is a cost-effective tool for the diagnosis of lysosomal storage disease. The purpose of this report is to define the ultrastructure of affected cells seen in skin biopsies of 2 boys whose mutation of OSTM1 has been characterized. The children presented in infancy with severe osteopetrosis and neurological deficiencies whose predominant symptoms were marked cerebral atrophy, decreased myelinization, and severe central nervous system involvement. Because of the difficulties in distinguishing this disorder from some lysosomal storage diseases such as mucopolysaccharidosis that have both neurological and skeletal abnormalities, the authors elected to examine skin biopsies from these children. Ultrastructural examination revealed the presence of swollen unmyelinated axons containing spheroids, reduced numbers of myelinated axons, and the presence of secondary lysosomes in Schwann cells containing lipofuscin. This study demonstrates that electron microscopy of skin biopsy is a useful diagnostic method to identify patients with clinical features of osteopetrosis with neuronal storage disease.     

Mixed Beverage of Fruits and Vegetables: Effect of Refrigerated Storage on Antioxidant Capacity and Acceptance

The aim of this work was to prepare a mixed beverage containing kale, ginger, coconut water, and orange, which is similar to the recipes found in the informal media, and to determine the effect of refrigerated storage on antioxidant, physical and chemical properties, ascorbic acid content, and sensory acceptance. The refrigeration of the mixed beverage for up to seven hours preserved the antioxidant properties, phenolic compounds, soluble solids, and titratable acidity but led to reduction of green color, pH, and ascorbic acid content. However, in the refrigeration for up to 25 hours, it was observed that antioxidant activity, color, pH, and ascorbic acid were not preserved. The beverage was considered appropriate by mean the sensory acceptance test, after microbiological analysis. The beverages refrigerated for 0, 13, and 25 hours were accepted, with maximum scores of 7 (10 cm scale), besides purchase intention above 3 on a 5-point scale.