16 research outputs found
Quality standards in upper gastrointestinal endoscopy: a position statement of the British Society of Gastroenterology (BSG) and Association of Upper Gastrointestinal Surgeons of Great Britain and Ireland (AUGIS)
The clinical and genetic spectrum of autosomal-recessive TOR1A-related disorders.
In the field of rare diseases, progress in molecular diagnostics led to the recognition that variants linked to autosomal-dominant neurodegenerative diseases of later onset can, in the context of biallelic inheritance, cause devastating neurodevelopmental disorders and infantile or childhood-onset neurodegeneration. TOR1A-associated arthrogryposis multiplex congenita 5 (AMC5) is a rare neurodevelopmental disorder arising from biallelic variants in TOR1A, a gene that in the heterozygous state is associated to torsion dystonia-1 (DYT1 or DYT-TOR1A), an early-onset dystonia with reduced penetrance. While 15 individuals with TOR1A-AMC5 have been reported (less than 10 in detail), a systematic investigation of the full disease-associated spectrum has not been conducted. Here, we assess the clinical, radiological and molecular characteristics of 57 individuals from 40 families with biallelic variants in TOR1A. Median age at last follow-up was 3 years (0-24 years). Most individuals presented with severe congenital flexion contractures (95%) and variable developmental delay (79%). Motor symptoms were reported in 79% and included lower limb spasticity and pyramidal signs, as well as gait disturbances. Facial dysmorphism was an integral part of the phenotype, with key features being a broad/full nasal tip, narrowing of the forehead and full cheeks. Analysis of disease-associated manifestations delineated a phenotypic spectrum ranging from normal cognition and mild gait disturbance to congenital arthrogryposis, global developmental delay, intellectual disability, absent speech and inability to walk. In a subset, the presentation was consistent with fetal akinesia deformation sequence with severe intrauterine abnormalities. Survival was 71% with higher mortality in males. Death occurred at a median age of 1.2 months (1 week - 9 years) due to respiratory failure, cardiac arrest, or sepsis. Analysis of brain MRI studies identified non-specific neuroimaging features, including a hypoplastic corpus callosum (72%), foci of signal abnormality in the subcortical and periventricular white matter (55%), diffuse white matter volume loss (45%), mega cisterna magna (36%) and arachnoid cysts (27%). The molecular spectrum included 22 distinct variants, defining a mutational hotspot in the C-terminal domain of the Torsin-1A protein. Genotype-phenotype analysis revealed an association of missense variants in the 3-helix bundle domain to an attenuated phenotype, while missense variants near the Walker A/B motif as well as biallelic truncating variants were linked to early death. In summary, this systematic cross-sectional analysis of a large cohort of individuals with biallelic TOR1A variants across a wide age-range delineates the clinical and genetic spectrum of TOR1A-related autosomal-recessive disease and highlights potential predictors for disease severity and survival
A methodology for identifying critical links and estimating macroscopic fundamental diagram in large-scale urban networks
The Macroscopic Fundamental Diagram (MFD), which exhibits the relationship between average flow and average density of an urban network, is a promising framework for monitoring and controlling urban traffic networks. Given that monitoring resources (e.g. loop detectors, probe vehicle data, etc.) are limited in real-world networks, acquiring adequate data to estimate an MFD is of crucial importance. This study presents a novel, network-wide approach to identifying critical links and estimating average traffic flow and density. The proposed model estimates the MFD using flow and density measurements from those critical links, which constitute only a small subset of all the links in the network. To find the critical links, we rely on historical probe vehicle data, and propose a model that builds on Principal Component Analysis (PCA), a dimensionality reduction and a feature selection method. Essentially, using PCA, a large number of possibly interrelated variables in a dataset can be reduced to a set of smaller uncorrelated variables, while maintaining as much information as possible in the dataset. The resulting uncorrelated variables, or the principal components, indicate the major patterns or the dominating features of the original dataset. Additionally, PCA enables the (approximate) reconstruction of the full-scale dataset from the selected features (or principal components). In this work, we apply PCA in order to identify the main traffic features from a probe vehicle dataset; then, we find the links that are associated with these features (i.e., critical links); then, we locate loop detectors on those links to collect flow and density data; and finally, we reconstruct the full-scale data, building on the PCA mechanism. This gives us the flow and density of all links, from which we can effectively estimate the MFD
Factors Associated With Lack of Vision Improvement in Children With Cortical Visual Impairment
Improvement in vision has been noted in children with cortical visual impairment (CVI), resulting from disparate types of brain injury. The purpose of our study was to determine the risk factors associated with poor recovery of vision in this group of patients. Case records of children who were born before 2010 with at least 4 follow-up visits for CVI were reviewed for underlying etiologies of CVI, visual acuity (VA), and associated neurological and ophthalmological disorders. VA was assessed in 6 qualitative grades. Changes in VA were recorded as the difference between the grades of VA at presentation and the last follow-up visit. The outcome was calculated as a ratio of actual improvement to potential improvement in grades of qualitative VA. Multiple linear regression determined factors associated with lack of vision improvement in all children and based on etiology. Fifty-three children with CVI were identified. The median age at presentation was 13.6 months (range: 2.9-76.4 months) and the median follow-up was 5.8 years (1.1-16.3 years). CVI resulted from central nervous system (CNS) malformation (9.4%), hypoxic/inflammatory injury (15.1%), seizures (24.5%), and combined causes (51.0%). Vision improvement was noted in 83% of children. Lack of VA improvement was associated with older age at presentation in all children with CVI and within each etiological group except CNS malformation. None of the other investigated variables were associated with poor recovery of VA. Most of the children with CVI showed improvement in vision. Older age at presentation, but not etiology of CVI, was associated with poor improvement in VA
The Fear of COVID-19 Scale: Development and Initial Validation
Background The emergence of the COVID-19 and its consequences has led to fears, worries, and anxiety among individuals worldwide.The present study developed the Fear of COVID-19 Scale (FCV-19S) to complement the clinical efforts in preventing the spread and treating of COVID-19 cases. Methods The sample comprised 717 Iranian participants. The items of the FCV-19S were constructed based on extensive review of existing scales on fears, expert evaluations, and participant interviews. Several psychometric tests were conducted to ascertain its reliability and validity properties. Results After panel review and corrected item-total correlation testing, seven items with acceptable corrected item-total correlation (0.47 to 0.56) were retained and further confirmed by significant and strong factor loadings (0.66 to 0.74). Also, other properties evaluatedusingbothclassicaltesttheoryandRaschmodelweresatisfactoryonthesevenitem scale. More specifically, reliability values such as internal consistency (α = .82) and test–retest reliability (ICC = .72) were acceptable. Concurrent validity was supported by the Hospital Anxiety and Depression Scale (with depression, r = 0.425 and anxiety, r = 0.511) and the Perceived Vulnerability to Disease Scale (with perceived infectability, r = 0.483 and germ aversion, r = 0.459). Conclusion The Fear of COVID-19 Scale, a seven-item scale, has robust psychometric properties. It is reliable and valid in assessing fear of COVID-19 among the general population and will also be useful in allaying COVID-19 fears among individuals
The Fear of COVID-19 Scale: Development and Initial Validation
Background The emergence of the COVID-19 and its consequences has led to fears, worries, and anxiety among individuals worldwide.The present study developed the Fear of COVID-19 Scale (FCV-19S) to complement the clinical efforts in preventing the spread and treating of COVID-19 cases. Methods The sample comprised 717 Iranian participants. The items of the FCV-19S were constructed based on extensive review of existing scales on fears, expert evaluations, and participant interviews. Several psychometric tests were conducted to ascertain its reliability and validity properties. Results After panel review and corrected item-total correlation testing, seven items with acceptable corrected item-total correlation (0.47 to 0.56) were retained and further confirmed by significant and strong factor loadings (0.66 to 0.74). Also, other properties evaluatedusingbothclassicaltesttheoryandRaschmodelweresatisfactoryonthesevenitem scale. More specifically, reliability values such as internal consistency (α = .82) and test–retest reliability (ICC = .72) were acceptable. Concurrent validity was supported by the Hospital Anxiety and Depression Scale (with depression, r = 0.425 and anxiety, r = 0.511) and the Perceived Vulnerability to Disease Scale (with perceived infectability, r = 0.483 and germ aversion, r = 0.459). Conclusion The Fear of COVID-19 Scale, a seven-item scale, has robust psychometric properties. It is reliable and valid in assessing fear of COVID-19 among the general population and will also be useful in allaying COVID-19 fears among individuals
Assessing bias in total mercury results after removing a subsample from the bottle
<p>U.S. EPA Method 1631 for total mercury (THg) analysis in water recommends that bromine monochloride (BrCl) be added to the original bottle in which the sample was collected, to draw into solution any Hg that may have adsorbed to the bottle walls. The method also allows for the removal of a subsample of water from the sample bottle for methylmercury (MeHg) analysis prior to adding BrCl. We have demonstrated that the removal of a subsample from the sample bottle prior to THg analysis can result in a positive concentration bias. The proposed mechanism for the bias is that ‘excess’ inorganic Hg, derived from the subsample that was removed from the bottle, adsorbs to the bottle walls and is then drawn into solution when BrCl is added. To test for this bias, we conducted an interlaboratory comparison study in which nine laboratories analysed water samples in fluorinated polyethylene (FLPE) bottles for THg after removing a subsample from the sample bottle, and analysed a replicate sample bottle from which no subsample was removed. We received seven complete data sets, or 63 unique sample pairs. The positive concentration bias between the bottles was significant when comparing all samples in aggregate (1.76 ± 0.53 ng/L after subsample removal, 1.57 ± 0.58 ng/L with no subsample removal, <i>P</i> < 0.05), however when comparing each of the three samples individually, the only significant bias was in the saline sample (Site UJ; 1.51 ± 0.31 ng/L after subsample removal, 1.32 ± 0.47 ng/L with no subsample removal, <i>P</i> < 0.05). Based on the findings presented here, we conclude that water chemistry, volume of water poured off, and the sample storage temperature explain some but not all of the observed bias, and we recommend collecting THg and MeHg samples in separate bottles whenever possible.</p
Coinfection modulates inflammatory responses and clinical outcome of Helicobacter felis and Toxoplasma gondii infections
The host immune response plays a critical role in determining disease manifestations of chronic infections. Inadequate immune response may fail to control infection, although in other cases the specific immune response may be the cause of tissue damage and disease. The majority of patients with chronic infections are infected by more than one organism yet the interaction between multiple active infections is not known, nor is the impact on disease outcome clear. Using the BALB/c strain of mice, we show that Toxoplasma gondii infection in a host infected with Helicobacter felis alters the natural outcome of T. gondii infection, allowing uncontrolled tachyzoite replication and severe organ damage. Survival rates decrease from 95% in T. gondii infection alone to 50% in dual-infected mice. In addition, infection with T. gondii alters the specific H. felis immune response, converting a previously resistant host to a susceptible phenotype. Gastric mucosal IFN-gamma and IL-12 were significantly elevated and IL-10 substantially reduced in dual-infected mice. These changes were associated with severe gastric mucosal inflammation, parietal cell loss, atrophy, and metaplastic cell changes. These data demonstrate the profound interactions between the immune response to unrelated organisms, and suggest these types of interactions my impact clinical disease