The misdiagnosis of epilepsy in people with intellectual disabilities: A systematic review

AbstractPurposeEpilepsy is common in people with intellectual disabilities. Epilepsy can be difficult to diagnose and may be misdiagnosed in around 25% of cases. A systematic review was conducted to explore:(i)How common the misdiagnosis of epilepsy is amongst people with intellectual disabilities.(ii)Reasons for misdiagnosis of epilepsy.(iii)Implications of misdiagnosis.(iv)Improving diagnosis.MethodsPrimary studies and systematic reviews published in the English language between 1998 and 2008 were identified from electronic databases, experts, the Internet, grey literature, and citation tracking. Included studies were critically appraised by team members using the appraisal tools produced by the Critical Appraisal Skills Programme (CASP) at the Public Health Resource Unit, Oxford.ResultsEight studies were included in the review and critically appraised: six cohort studies and two case studies. Where data was provided in the cohort studies between 32% and 38% of people with intellectual disabilities were diagnosed as not having epilepsy or as having nonepileptic events. The main reason for misdiagnosis was the misinterpretation of behavioural, physiological, syndrome related, medication related or psychological events by parents, paid carers and health professionals.ConclusionsThose working in epilepsy and intellectual disability services and families must be made more aware of the possibility of misdiagnosis. Future research is needed about the misdiagnosis of epilepsy amongst people with intellectual disabilities and carer knowledge

Predators catalyze an increase in chloroviruses by foraging on the symbiotic hosts of zoochlorellae

Virus population growth depends on contacts between viruses and their hosts. It is often unclear how sufficient contacts are made between viruses and their specific hosts to generate spikes in viral abundance. Here, we show that copepods, acting as predators, can bring aquatic viruses and their algal hosts into contact. Specifically, predation of the protist Paramecium bursaria by copepods resulted in a \u3e100-fold increase in the number of chloroviruses in 1 d. Copepod predation can be seen as an ecological “catalyst” by increasing contacts between chloroviruses and their hosts, zoochlorellae (endosymbiotic algae that live within paramecia), thereby facilitating viral population growth. When feeding, copepods passed P. bursaria through their digestive tract only partially digested, releasing endosymbiotic algae that still supported viral reproduction and resulting in a virus population spike. A simple predator–prey model parameterized for copepods consuming protists generates cycle periods for viruses consistent with those observed in natural ponds. Food webs are replete with similar symbiotic organisms, and we suspect the predator catalyst mechanism is capable of generating blooms for other endosymbiont-targeting viruses. Movie file (.mp4) attached below

Predators catalyze an increase in chloroviruses by foraging on the symbiotic hosts of zoochlorellae

Virus population growth depends on contacts between viruses and their hosts. It is often unclear how sufficient contacts are made between viruses and their specific hosts to generate spikes in viral abundance. Here, we show that copepods, acting as predators, can bring aquatic viruses and their algal hosts into contact. Specifically, predation of the protist Paramecium bursaria by copepods resulted in a \u3e100-fold increase in the number of chloroviruses in 1 d. Copepod predation can be seen as an ecological “catalyst” by increasing contacts between chloroviruses and their hosts, zoochlorellae (endosymbiotic algae that live within paramecia), thereby facilitating viral population growth. When feeding, copepods passed P. bursaria through their digestive tract only partially digested, releasing endosymbiotic algae that still supported viral reproduction and resulting in a virus population spike. A simple predator–prey model parameterized for copepods consuming protists generates cycle periods for viruses consistent with those observed in natural ponds. Food webs are replete with similar symbiotic organisms, and we suspect the predator catalyst mechanism is capable of generating blooms for other endosymbiont-targeting viruses. Movie file (.mp4) attached below

Chloroviruses have a sweet tooth

Chloroviruses are large double-stranded DNA (dsDNA) viruses that infect certain isolates of chlorella-like green algae. They contain up to approximately 400 protein-encoding genes and 16 transfer RNA (tRNA) genes. This review summarizes the unexpected finding that many of the chlorovirus genes encode proteins involved in manipulating carbohydrates. These include enzymes involved in making extracellular polysaccharides, such as hyaluronan and chitin, enzymes that make nucleotide sugars, such as GDP-L-fucose and GDP-D-rhamnose and enzymes involved in the synthesis of glycans attached to the virus major capsid proteins. This latter process differs from that of all other glycoprotein containing viruses that traditionally use the host endoplasmic reticulum and Golgi machinery to synthesize and transfer the glycans

Lifelongα-tocopherol supplementation increases the median life span of C57BL/6 mice in the cold but has only minor effects on oxidative damage

The effects of dietary antioxidant supplementation on oxidative stress and life span are confused. We maintained C57BL/6 mice at 7 ± 2°C and supplemented their diet with α-tocopherol from 4 months of age. Supplementation significantly increased (p = 0.042) median life span by 15% (785 days, n = 44) relative to unsupplemented controls (682 days, n = 43) and also increased maximum life span (oldest 10%, p = 0.028). No sex or sex by treatment interaction effects were observed on life span, with treatment having no effect on resting or daily metabolic rate. Lymphocyte and hepatocyte oxidative DNA damage and hepatic lipid peroxidation were unaffected by supplementation, but hepatic oxidative DNA damage increased with age. Using a cDNA macroarray, genes associated with xenobiotic metabolism were significantly upregulated in the livers of female mice at 6 months of age (2 months supplementation). At 22 months of age (18 months supplementation) this response had largely abated, but various genes linked to the p21 signaling pathway were upregulated at this time. We suggest that α-tocopherol may initially be metabolized as a xenobiotic, potentially explaining why previous studies observe a life span extension generally when lifelong supplementation is initiated early in life. The absence of any significant effect on oxidative damage suggests that the life span extension observed was not mediated via any antioxidant properties of α-tocopherol. We propose that the life span extension observed following α-tocopherol supplementation may be mediated via upregulation of cytochrome p450 genes after 2 months of supplementation and/or upregulation of p21 signaling genes after 18 months of supplementation. However, these signaling pathways now require further investigation to establish their exact role in life span extension following α-tocopherol supplementation

Measurement of person-centred consultation skills among healthcare practitioners: a systematic review of reviews of validation studies

Background: Person-centred care is integral to high-quality health service provision, though concepts vary and the literature is complex. Validated instruments that measure person-centred practitioner skills, and behaviours within consultations, are needed for many reasons, including in training programmes. We aimed to provide a high-level synthesis of what was expected to be a large and diverse literature through a systematic review of existing reviews of validation studies a of instruments that measure person-centred practitioner skills and behaviours in consultations. The objectives were to undertake a critical appraisal of these reviews, and to summarise the available validated instruments and the evidence underpinning them. Methods: A systematic search of Medline, EMBASE, PsycINFO and CINAHL was conducted in September 2020. Systematic reviews of validation studies of instruments measuring individual practitioner person-centred consultation skills or behaviours which report measurement properties were included. Review quality was assessed with the Joanna Briggs Institute Critical Appraisal Checklist for Systematic Reviews and Research Syntheses. Details of the reviews, the included validation studies, and the instruments themselves are tabulated, including psychometric data, and a narrative overview of the reviews is provided. Results: Four reviews were eligible for inclusion. These used different conceptualisations of person-centredness and targeted distinct, sometimes mutually exclusive, practitioners and settings. The four reviews included 68 unique validation studies examining 42 instruments, but with very few overlaps. The critical appraisal shows there is a need for improvements in the design of reviews in this area. The instruments included within these reviews have not been subject to extensive validation study. Discussion: There are many instruments available which measure person-centred skills in healthcare practitioners and this study offers a guide to what is available to researchers and research users. The most relevant and promising instruments that have already been developed, or items within them, should be further studied rigorously. Validation study of existing material is needed, not the development of new measures

A novel class of CoA-transferase involved in short-chain fatty acid metabolism in butyrate-producing human colonic bacteria

Peer reviewedPublisher PD

Identification of an L-Rhamnose Synthetic Pathway in Two Nucleocytoplasmic Large DNA Viruses

Nucleocytoplasmic large DNA viruses (NCLDVs) are characterized by large genomes that often encode proteins not commonly found in viruses. Two species in this group are Acanthocystis turfacea chlorella virus 1 (ATCV-1) (family Phycodnaviridae, genus Chlorovirus) and Acanthamoeba polyphaga mimivirus (family Mimiviridae), commonly known as mimivirus. ATCV-1 and other chlorovirus members encode enzymes involved in the synthesis and glycosylation of their structural proteins. In this study, we identified and characterized three enzymes responsible for the synthesis of the sugar L-rhamnose: two UDP-D-glucose 4,6-dehydratases (UGDs) encoded by ATCV-1 and mimivirus and a bifunctional UDP-4-keto-6-deoxy-D-glucose epimerase/reductase (UGER) from mimivirus. Phylogenetic analysis indicated that ATCV-1 probably acquired its UGD gene via a recent horizontal gene transfer (HGT) from a green algal host, while an earlier HGT event involving the complete pathway (UGD and UGER) probably occurred between a protozoan ancestor and mimivirus. While ATCV-1 lacks an epimerase/reductase gene, its Chlorella host may encode this enzyme. Both UGDs and UGER are expressed as late genes, which is consistent with their role in posttranslational modification of capsid proteins. The data in this study provide additional support for the hypothesis that chloroviruses, and maybe mimivirus, encode most, if not all, of the glycosylation machinery involved in the synthesis of specific glycan structures essential for virus replication and infection

Chloroviruses \u3ci\u3eN\u3c/i\u3e-linked glycans share a new type of conserved core architecture unprecedented in any form of life / [Published as] N-Linked Glycans of Chloroviruses Sharing a Core Architecture without Precedent

N-glycosylation is a fundamental modification of proteins that exists in the three domains of life and in some viruses, including the chloroviruses, for which a new type of core N-glycan is described. This N-glycan core structure common to all chloroviruses is a pentasaccharide with a β-glucose linked to an asparagine residue that is not located in the typical sequon N-X-T/S. The glucose is linked to a terminal xylose unit and a hyperbranched fucose, in turn substituted with a terminal galactose and a second xylose residue. The third position of the fucose unit is always linked to a rhamnose, which is a semi-conserved element because its absolute configuration is virus-dependent. Additional decorations occur on this core N-glycan and represent a molecular signature for each chlorovirus. Includes supplemental materials

Identification of a Chlorovirus PBCV-1 Protein Involved in Degrading the Host Cell Wall during Virus Infection

Chloroviruses are unusual among viruses infecting eukaryotic organisms in that they must, like bacteriophages, penetrate a rigid cell wall to initiate infection. Chlorovirus PBCV-1 infects its host, Chlorella variabilis NC64A by specifically binding to and degrading the cell wall of the host at the point of contact by a virus-packaged enzyme(s). However, PBCV-1 does not use any of the five previously characterized virus-encoded polysaccharide degrading enzymes to digest the Chlorella host cell wall during virus entry because none of the enzymes are packaged in the virion. A search for another PBCV-1-encoded and virion-associated protein identified protein A561L. The fourth domain of A561L is a 242 amino acid C-terminal domain, named A561LD4, with cell wall degrading activity. An A561LD4 homolog was present in all 52 genomically sequenced chloroviruses, infecting four different algal hosts. A561LD4 degraded the cell walls of all four chlorovirus hosts, as well as several non-host Chlorella spp. Thus, A561LD4 was not cell-type specific. Finally, we discovered that exposure of highly purified PBCV-1 virions to A561LD4 increased the specific infectivity of PBCV-1 from about 25–30% of the particles forming plaques to almost 50%. We attribute this increase to removal of residual host receptor that attached to newly replicated viruses in the cell lysates