450 research outputs found
Application of multiple-wireless to a visual localisation system for emergency services
AbstractâIn this paper we discuss the application of multiplewireless technology to a practical context-enhanced service system called ViewNet. ViewNet develops technologies to support enhanced coordination and cooperation between operation teams in the emergency services and the police. Distributed localisation of users and mapping of environments implemented over a secure wireless network enables teams of operatives to search and map an incident area rapidly and in full coordination with each other and with a control centre. Sensing is based on fusing absolute positioning systems (UWB and GPS) with relative localisation and mapping from on-body or handheld vision and inertial sensors. This paper focuses on the case for multiple-wireless capabilities in such a system and the benefits it can provide. We describe our work of developing a software API to support both WLAN and TETRA in ViewNet. It also provides a basis for incorporating future wireless technologies into ViewNet. I
The genetics of intellectual disability: advancing technology and gene editing [version 1; peer review: 2 approved]
Intellectual disability (ID) is a neurodevelopmental condition affecting 1â3% of the worldâs population. Genetic factors play a key role causing the congenital limitations in intellectual functioning and adaptive behavior. The heterogeneity of ID makes it more challenging for genetic and clinical diagnosis, but the advent of large-scale genome sequencing projects in a trio approach has proven very effective. However, many variants are still difficult to interpret. A combined approach of next-generation sequencing and functional, electrophysiological, and bioinformatics analysis has identified new ways to understand the causes of ID and help to interpret novel ID-causing genes. This approach offers new targets for ID therapy and increases the efficiency of ID diagnosis. The most recent functional advancements and new gene editing techniques involving the use of CRISPRâCas9 allow for targeted editing of DNA in in vitro and more effective mammalian and human tissue-derived disease models. The expansion of genomic analysis of ID patients in diverse and ancient populations can reveal rare novel disease-causing genes
A Review of Copy Number Variants in Inherited Neuropathies
The rapid development in the last 10-15 years of microarray technologies, such as oligonucleotide
array Comparative Genomic Hybridization (CGH) and Single Nucleotide Polymorphisms
(SNP) genotyping array, has improved the identification of fine chromosomal structural variants, ranging
in length from kilobases (kb) to megabases (Mb), as an important cause of genetic differences
among healthy individuals and also as disease-susceptibility and/or disease-causing factors. Structural
genomic variations due to unbalanced chromosomal rearrangements are known as Copy-Number
Variants (CNVs) and these include variably sized deletions, duplications, triplications and translocations.
CNVs can significantly contribute to human diseases and rearrangements in several dosagesensitive
genes have been identified as an important causative mechanism in the molecular aetiology
of Charcot-Marie-Tooth (CMT) disease and of several CMT-related disorders, a group of inherited
neuropathies with a broad range of clinical phenotypes, inheritance patterns and causative genes. Duplications
or deletions of the dosage-sensitive gene PMP22 mapped to chromosome 17p12 represent
the most frequent causes of CMT type 1A and Hereditary Neuropathy with liability to Pressure Palsies
(HNPP), respectively. Additionally, CNVs have been identified in patients with other CMT types
(e.g., CMT1X, CMT1B, CMT4D) and different hereditary poly- (e.g., giant axonal neuropathy) and
focal- (e.g., hereditary neuralgic amyotrophy) neuropathies, supporting the notion of hereditary peripheral
nerve diseases as possible genomic disorders and making crucial the identification of fine
chromosomal rearrangements in the molecular assessment of such patients. Notably, the application of
advanced computational tools in the analysis of Next-Generation Sequencing (NGS) data has emerged
in recent years as a powerful technique for identifying a genome-wide scale complex structural variants
(e.g., as the ones resulted from balanced rearrangements) and also smaller pathogenic (intragenic)
CNVs that often remain beyond the detection limit of most conventional genomic microarray analyses;
in the context of inherited neuropathies where more than 70 disease-causing genes have been
identified to date, NGS and particularly Whole-Genome Sequencing (WGS) hold the potential to reduce
the number of genomic assays required per patient to reach a diagnosis, analyzing with a single
test all the Single Nucleotide Variants (SNVs) and CNVs in the genes possibly implicated in this
heterogeneous group of disorders
Determination of APTT factor sensitivity - the misguiding guideline.
INTRODUCTION: The Clinical and Laboratory Standards Institute (CLSI) has produced a guideline detailing how to determine the activated partial thromboplastin time's (APTT) sensitivity to clotting factor deficiencies, by mixing normal and deficient plasmas. Using the guideline, we determined the factor sensitivity of two APTT reagents. METHODS: APTTs were performed using Actin FS and Actin FSL on a Sysmex CS-5100 analyser. The quality of factor-deficient and reference plasmas from three commercial sources was assessed by assaying each of the clotting factors within the plasmas and by performing thrombin generation tests (TGT). RESULTS: Testing samples from 50 normal healthy subjects gave a two-standard deviation range of 21.8-29.2Â s for Actin FS and 23.5-29.3Â s for Actin FSL. The upper limits of these ranges were subsequently used to determine APTT factor sensitivity. Assay of factor levels within the deficient plasmas demonstrated that they were specifically deficient in a single factor, with most other factors in the range 50-150Â iu/dL (Technoclone factor VII-deficient plasma has 26Â iu/dL factor IX). APTTs performed on mixtures of normal and deficient plasmas gave diverse sensitivity to factor deficiencies dependent on the sources of deficient plasma. TGT studies on the deficient plasmas revealed that the potential to generate thrombin was not solely associated with the levels of their component clotting factors. CONCLUSION: Determination of APTT factor sensitivity in accordance with the CLSI guideline can give inconsistent and misleading results
Coexistent antiphospholipid syndrome and myeloproliferative neoplasm
Antiphospholipid syndrome (APS) and myeloproliferative neoplasms (MPN) are associated with an increased risk of thrombosis. The optimal management of patients with coexistent APS and MPN has not been defined. A single centre and systematic literature review of patients with coexistent APS and MPN was performed. Cases were divided into two groups based on whether they met international consensus criteria for APS. Of the 12 studies identified, eight were excluded (leaving five of a total 54 patients), as although antiphospholipid antibodies (aPL) were documented, the diagnosis of APS was not conclusively demonstrated. Another ten patients with definite APS were identified at our centre. Fifteen patients (ten females, five males) were therefore included in this analysis (eleven definite APS and four highly likely), median age 44 (range: 13â71) years. Nine had polycythaemia vera and six, essential thrombocythaemia. Thirteen of the 15 patients (86.7%) had thrombotic APS (seven with initial venous events and six arterial) and two (13.3%) had obstetric APS. Nine patients were single-positive, and six double-positive for aPL. None were triple aPL-positive. Four patients at our centre had recurrent thrombotic/obstetric events, including while on anticoagulation/antiplatelet treatment
Novel variants underlying autosomal recessive intellectual disability in Pakistani consanguineous families
Background: Intellectual disability (ID) is both a clinically diverse and genetically heterogeneous group of disorder,
with an onset of cognitive impairment before the age of 18 years. ID is characterized by significant limitations in
intellectual functioning and adaptive behaviour. The identification of genetic variants causing ID and neurodevelopmental
disorders using whole-exome sequencing (WES) has proven to be successful. So far more than 1222 primary and 1127
candidate genes are associated with ID.
Methods: To determine pathogenic variants causative of ID in three unrelated consanguineous Pakistani families, we used a
combination of WES, homozygosity-by-descent mapping, de-deoxy sequencing and bioinformatics analysis.
Results: Rare pathogenic single nucleotide variants identified by WES which passed our filtering strategy were confirmed by
traditional Sanger sequencing and segregation analysis. Novel and deleterious variants in VPS53, GLB1, and MLC1, genes
previously associated with variable neurodevelopmental anomalies, were found to segregate with the disease in the three
families.
Conclusions: This study expands our knowledge on the molecular basis of ID as well as the clinical heterogeneity associated
to different rare genetic causes of neurodevelopmental disorders. This genetic study could also provide
additional knowledge to help genetic assessment as well as clinical and social management of ID in Pakistani
familie
Comparison of the gene expression profiles of human fetal cortical astrocytes with pluripotent stem cell derived neural stem cells identifies human astrocyte markers and signaling pathways and transcription factors active in human astrocytes
Astrocytes are the most abundant cell type in the central nervous system (CNS) and have a multitude of functions that include maintenance of CNS homeostasis, trophic support of neurons, detoxification, and immune surveillance. It has only recently been appreciated that astrocyte dysfunction is a primary cause of many neurological disorders. Despite their importance in disease very little is known about global gene expression for human astrocytes. We have performed a microarray expression analysis of human fetal astrocytes to identify genes and signaling pathways that are important for astrocyte development and maintenance. Our analysis confirmed that the fetal astrocytes express high levels of the core astrocyte marker GFAP and the transcription factors from the NFI family which have been shown to play important roles in astrocyte development. A group of novel markers were identified that distinguish fetal astrocytes from pluripotent stem cell-derived neural stem cells (NSCs) and NSC-derived neurons. As in murine astrocytes, the Notch signaling pathway appears to be particularly important for cell fate decisions between the astrocyte and neuronal lineages in human astrocytes. These findings unveil the repertoire of genes expressed in human astrocytes and serve as a basis for further studies to better understand astrocyte biology, especially as it relates to disease.published_or_final_versio
BrownâVialettoâVan Laere and FazioâLonde syndromes: SLC52A3 mutations with puzzling phenotypes and inheritance
BACKGROUND: Brown-Vialetto-Van Laere Syndrome (BVVLS) and Fazio-Londe Disease (FLD) are rare neurological disorders presenting with pontobulbar palsy, muscle weakness, and respiratory insufficiency. Mutations in SLC52A2 (hRFVT-2) or SLC52A3 (hRFVT-3) genes can be responsible for these disorders with an autosomal recessive pattern of inheritance. The aim of this study is to screen for mutations in SLC52A2 and SLC52A3 among Indian families diagnosed with BVVLS and FLD. METHODS: SLC52A2 and SLC52A3 were screened in one FLD and three BVVLS patients by exon-specific amplification using PCR and sequencing. In silico predictions using bioinformatics tools and confocal imaging using HEK-293 cells were performed to determine the functional impact of identified mutations. RESULTS: Genetic analysis of a mother and son with BVVLS was identified with a novel homozygous mutation c.710C>T (p.Ala237Val) in SLC52A3. This variant was found to have autosomal pseudo-dominant pattern of inheritance, which was neither listed in the Exome variant server or in 1000 genomes database. In silico analysis and confocal imaging of the p.Ala237Val variant showed higher degree of disorderness in hRFVT3 that could affect riboflavin transport. Furthermore, a common homozygous mutation c.62A>G (p.Asn21Ser) was identified in other BVVLS and FLD patients. Despite having different clinical phenotypes, both BVVLS and FLD disorder can be attributed to this mutation. CONCLUSION: A rare and peculiar pattern of autosomal pseudo-dominant inheritance is observed for the first time in two genetically related BVVLS cases with Indian origin and a common mutation c.62A>G (p.Asn21Ser) in SLC52A3 can be responsible for both BVVLS and FLD with variable phenotypes
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Minimally invasive colorectal cancer procedures in patients with obesity: an interdisciplinary approach.
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