Cyclin D1 overexpression supports stable EBV infection in nasopharyngeal epithelial cells

Undifferentiated nasopharyngeal carcinomas (NPCs) are commonly present with latent EBV infection. However, events regulating EBV infection at early stages of the disease and the role of EBV in disease pathogenesis are largely undefined. Genetic alterations leading to activation of cyclin D1 signaling in premalignant nasopharyngeal epithelial (NPE) cells have been postulated to predispose cells to EBV infection. We previously reported that loss of p16, a negative regulator of cyclin D1 signaling, is a frequent feature of NPC tumors. Here, we report that early premalignant lesions of nasopharyngeal epithelium overexpress cyclin D1. Furthermore, overexpression of cyclin D1 is closely associated with EBV infection. Therefore we investigated the potential role of cyclin D1 overexpression in dysplastic NPE cells in vitro. In human telomerase reverse transcriptase-immortalized NPE cells, overexpression of cyclin D1 or a p16-resistant form of CDK4 (CDK4(R24C)) suppressed differentiation. This suppression may have implications for the close association of EBV infection with undifferentiated NPC. In these in vitro models, we found that cellular growth arrest and senescence occurred in EBV-infected cell populations immediately after infection. Nevertheless, overexpression of cyclin D1 or a p16-resistant form of CDK4 or knockdown of p16 in the human telomerase reverse transcriptase-immortalized NPE cell lines could counteract the EBV-induced growth arrest and senescence. We conclude that dysregulated expression of cyclin D1 in NPE cells may contribute to NPC pathogenesis by enabling persistent infection of EBV.published_or_final_versio

Cerebrospinal fluid neurogranin concentration in neurodegeneration: relation to clinical phenotypes and neuropathology

Neurogranin (Ng) is a post-synaptic protein that previously has been shown to be a biomarker for synaptic function when measured in cerebrospinal fluid (CSF). The CSF concentration of Ng is increased in Alzheimer's disease dementia (ADD), and even in the pre-dementia stage. In this prospective study, we used an enzyme-linked immunosorbent assay that quantifies Ng in CSF to test the performance of Ng as a marker of synaptic function. In 915 patients, CSF Ng was evaluated across several different neurodegenerative diseases. Of these 915 patients, 116 had a neuropathologically confirmed definitive diagnosis and the relation between CSF Ng and topographical distribution of different pathologies in the brain was evaluated. CSF Ng was specifically increased in ADD compared to eight other neurodegenerative diseases, including Parkinson's disease (p < 0.0001), frontotemporal dementia (p < 0.0001), and amyotrophic lateral sclerosis (p = 0.0002). Similar results were obtained in neuropathologically confirmed cases. Using a biomarker index to evaluate whether CSF Ng contributed diagnostic information to the core AD CSF biomarkers (amyloid β (Aβ), t-tau, and p-tau), we show that Ng significantly increased the discrimination between AD and several other disorders. Higher CSF Ng levels were positively associated with greater Aβ neuritic plaque (Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuritic plaque score, p = 0.0002) and tau tangle pathology (Braak neurofibrillary tangles staging, p = 0.0007) scores. In the hippocampus and amygdala, two brain regions heavily affected in ADD with high expression of Ng, CSF Ng was associated with plaque (p = 0.0006 and p < 0.0001), but not with tangle, α-synuclein, or TAR DNA-binding protein 43 loads. These data support that CSF Ng is increased specifically in ADD, that high CSF Ng concentrations likely reflect synaptic dysfunction and that CSF Ng is associated with β-amyloid plaque pathology

Elevated CSF GAP-43 is Alzheimer's disease specific and associated with tau and amyloid pathology

Introduction: The level of the presynaptic protein growth-associated protein 43 (GAP-43) in cerebrospinal fluid (CSF) has previously been shown to be increased in Alzheimer's disease (AD) and thus may serve as an outcome measure in clinical trials and facilitate earlier disease detection. / Methods: We developed an enzyme-linked immunosorbent assay for CSF GAP-43 and measured healthy controls (n = 43), patients with AD (n = 275), or patients with other neurodegenerative diseases (n = 344). In a subpopulation (n = 93), CSF GAP-43 concentrations from neuropathologically confirmed cases were related to Aβ plaques, tau, α-synuclein, and TDP-43 pathologies. / Results: GAP-43 was significantly increased in AD compared to controls and most neurodegenerative diseases and correlated with the magnitude of neurofibrillary tangles and Aβ plaques in the hippocampus, amygdala, and cortex. GAP-43 was not associated to α-synuclein or TDP-43 pathology. / Discussion: The presynaptic marker GAP-43 is associated with both diagnosis and neuropathology of AD and thus may be useful as a sensitive and specific biomarker for clinical research

Diagnosis and management of dementia with Lewy bodies: Fourth consensus report of the DLB Consortium

The Dementia with Lewy Bodies (DLB) Consortium has refined its recommendations about the clinical and pathologic diagnosis of DLB, updating the previous report, which has been in widespread use for the last decade. The revised DLB consensus criteria now distinguish clearly between clinical features and diagnostic biomarkers, and give guidance about optimal methods to establish and interpret these. Substantial new information has been incorporated about previously reported aspects of DLB, with increased diagnostic weighting given to REM sleep behavior disorder and $^{123}$iodine-metaiodobenzylguanidine (MIBG) myocardial scintigraphy. The diagnostic role of other neuroimaging, electrophysiologic, and laboratory investigations is also described. Minor modifications to pathologic methods and criteria are recommended to take account of Alzheimer disease neuropathologic change, to add previously omitted Lewy-related pathology categories, and to include assessments for substantia nigra neuronal loss. Recommendations about clinical management are largely based upon expert opinion since randomized controlled trials in DLB are few. Substantial progress has been made since the previous report in the detection and recognition of DLB as a common and important clinical disorder. During that period it has been incorporated into DSM-5, as major neurocognitive disorder with Lewy bodies. There remains a pressing need to understand the underlying neurobiology and pathophysiology of DLB, to develop and deliver clinical trials with both symptomatic and disease-modifying agents, and to help patients and carers worldwide to inform themselves about the disease, its prognosis, best available treatments, ongoing research, and how to get adequate support.The DLB Consortium meeting was organized by the Mayo School of Continuous Professional Development (MSCPD) and supported by Acadia Pharmaceuticals, Alzheimer’s Association, Axovant Sciences, Banner Health, GE Healthcare, the Lewy Body Dementia Association, the Lewy Body Society, Lundbeck, the National Institute on Aging, the National Institute on Neurologic Disease and Stroke, and an NIH grant (R13 NS095618). Kathy Fuqua, Julie Reed, and colleagues at the MSCPD provided administrative support to the consortium meeting in Fort Lauderdale. I.G.M., D.B., J.-P.T., J.A., and A.T. receive support from the UK NIHR Biomedical Research Centre awarded to the Newcastle upon Tyne Hospitals NHS Foundation Trust and Newcastle University. Travel grant support was provided by the Alzheimer’s Research UK ARUK NE Network Centre. B.F.B., D.W.D., K.K., and T.J.F. are supported by the NIH (P50-AG016574) and the Mangurian Foundation for Lewy Body Research. G.H. is a senior principal research fellowship holder from the National Health and Medical Research Council of Australia (1079679). D.A. is a Royal Society Wolfson Research Merit Award Holder and thanks the Wolfson Foundation and the Royal Society for their support. C.G.B. thanks the Maudsley BRC for Mental Health and BRU dementia for supporting his involvement in the work. A.C.-P. receives research support from the NIH (RO1 NS082265, UO1 NS082134, P50 NS053488), the Burroughs Wellcome Fund, the Alzheimer’s Association/Michael J. Fox Foundation/Weston Biomarkers Across Neurodegenerative Disease initiative, and the Pechenik Montague Award Fund. D.f. acknowledges support from NIHR Programme Grants for Applied Research (RP-PG-0610-10100 SHAPED). O.E.-A. acknowledges support for OE laboratory from the Michael J. Fox Foundation for Parkinson’s Research (New York). S.N.G. receives support from R21 NS 090243 and the National Parkinson’s Foundation. O.A.R. is supported through the Mayo Clinic: A Morris K. Udall Parkinson’s Disease Research Center of Excellence (NINDS P50 NS072187), NINDS R01 NS078086, the Michael J. Fox Foundation for Parkinson’s Research, the Mayo Clinic AD and Related Dementias Genetics Program, and The Little Family Foundation. A.S.’s work is supported by the Intramural Research Program of the National Institute on Aging, Department of Health and Human Services. D.T. acknowledges the work of Cyrus Zabetian, MD, and Ignacio Mata, PhD, from VA Puget Sound Health Care System. J.Q.T. and V.M.Y.L.’s contributions were supported in part by a P50 NS053488 Morris K. Udall Parkinson’s Disease Research Center of Excellence grant from NINDS. P.T. acknowledges support from the Italian Ministry of Health “Ricerca Corrente.” M.Y. acknowledges support from the Japan Foundation for Neuroscience and Mental Health

Procoagulant platelets and the pathways leading to cell death

Platelets are critical mediators of thrombosis and hemostasis. In response to agonist, platelets aggregate to form a thrombus via ligand binding of the glycoprotein IIb/IIIa receptor. However, activated platelets are heterogeneous in nature and a subset of platelets stimulated by strong agonists support the assembly of the coagulation complexes. It is proposed that these procoagulant platelets have a unique role in hemostasis and thrombosis as the link between primary and secondary hemostasis, localizing the thrombin burst required for fibrin formation to micro-domains within the platelet thrombus. Loss of procoagulant potential leads to bleeding while an increase is linked with propensity to thrombosis. While many features of the procoagulant platelet are known, the exact nature of the procoagulant platelet remains controversial. It is noted that many of the morphological and biochemical features of procoagulant platelets are also features of the cyclophilin D necrosis pathway. This review will focus on the distinct roles of platelet subpopulations, the identity of the procoagulant platelet, and the potential role of the cell death pathways in regulating platelet procoagulant response

Enumeration of extracellular vesicles by a new improved flow cytometric method is comparable to fluorescence mode nanoparticle tracking analysis

Extracellular vesicles (EVs) play a role in a variety of physiological and pathological processes. However, use of EVs as biomarkers has been hampered by limitations of current detection and enumeration methods. We compared fluorescence-threshold flow cytometry (FT-FC) to nanoparticle tracking analysis (NTA) for enumeration of cell culture-derived EVs. FT-FC and NTA utilising fluorescence mode (F-NTA) enumerated similar numbers of EVs stained with a membrane dye PKH67. Both methods were sufficiently sensitive to detect cell-derived EVs above the background of culture medium. Light scatter NTA (LS-NTA) detected 10-100. × more particles than either fluorescence-based method but demonstrated poor specificity. F-NTA appeared to have better sensitivity for 100 nm range. Due to wider availability and higher degree of automation and standardisation, FT-FC is a reasonable surrogate to F-NTA for quantification of EVs

Necrotic platelets provide a procoagulant surface during thrombosis

A subpopulation of platelets fulfills a procoagulant role in hemostasis and thrombosis by enabling the thrombin burst required for fibrin formation and clot stability at the site of vascular injury. Excess procoagulant activity is linked with pathological thrombosis. The identity of the procoagulant platelet has been elusive. The cell death marker 4-[N-(S-glutathionylacetyl)amino]phenylarsonous acid (GSAO) rapidly enters a subpopulation of agonist-stimulated platelets via an organic anion-transporting polypeptide and is retained in the cytosol through covalent reaction with protein dithiols. Labeling with GSAO, together with exposure of P-selectin, distinguishes necrotic from apoptotic platelets and correlates with procoagulant potential. GSAO+ platelets form in occluding murine thrombi after ferric chloride injury and are attenuated withmegakaryocyte-directed deletionof the cyclophilin D gene. These platelets forma procoagulant surface, supporting fibrin formation, and reduction in GSAO+ platelets is associated with reduction in platelet thrombus size and fibrin formation. Analysis of platelets from human subjects receiving aspirin therapy indicates that these procoagulant platelets form despite aspirin therapy, but are attenuated by inhibition of the necrosis pathway. These findings indicate that the major subpopulation of platelets involved in fibrin formation are formed via regulated necrosis involving cyclophilin D, and that they may be targeted independent of platelet activation

Pediatric Sedation: The Asian Approach - Current State of Sedation in China

In China, the need for sedation and analgesia for both diagnostic and therapeutic procedures performed outside the operating room has increased dramatically in recent years. In China there are currently no national guidelines on providing sedation to either children or adults. Hong Kong, although a Special Administrative Region of the Peoples Republic of China (PRC), has its own independent Academy of Medicine, which does issue guidelines. For the purpose of this chapter, the authors will consider Hong Kong as separate from China, since currently the two regions approach sedation in a vastly different manner. In order to understand the current state of pediatric sedation, a survey was sent to 41 hospitals, all members of the Pediatric Anesthesia Association in China. The size of hospitals ranged from 500 to 4,200 beds and the number of pediatric operations performed in these hospitals ranged from 3,000 to 60,000 in 2012. The response rate was 53.6 %. Of the 22 completed surveys, five hospitals responded that they had no sedation service (their surveys were not returned) and two indicated that anesthesiologists are not involved in their sedation services