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Cureus Apr 202390% of visually impaired people live in developing countries. There are various types of vision impairment, but the focus of the current study is retinitis pigmentosa...
INTRODUCTION
90% of visually impaired people live in developing countries. There are various types of vision impairment, but the focus of the current study is retinitis pigmentosa (RP). Up to now, 150 mutations have been reported that are linked with RP.
METHODOLOGY
Healthy and affected members from two Pakistani families (RP01 and RP02) segregating autosomal recessive RP were selected for DNA extraction. PCR was conducted, and the amplified PCR products were analyzed using Polyacrylamide Gel Electrophoresis (PAGE) and visualized in the Gel Doc system for linkage analysis. The Gene Hunter 2.1r5 tool in the Simple Linkage v5.052 beta software suite was used to conduct multipoint parametric linkage analysis on the two consanguineous families examined on the 6K Illumina array. Exons and intron-exon borders of all known arRP genes found in homozygous areas were sequenced in the matching probands using a 3130 automated sequencer and the Big Dye Terminator Cycle Sequencing Kit v3.1. The mutation study was carried out using the AlaMut 1.5 program.
RESULTS
In both families, linkage analysis was performed using microsatellite marker DIS422 for gene and microsatellite marker D8S2332 for gene . Multipoint linkage analysis identifies genomic regions that could potentially contain the genetic defect. In family RP01, only a single peak with a maximal multipoint LOD score of 3.00 was identified on chromosome 1, whereas in family RP02, multiple peaks with multipoint LOD scores of 1.80 were identified on chromosome 8. Analysis of the gene revealed a homozygous substitution of glycine for valine (c.1152T>G; p.V243G), whereas the gene demonstrated that leucine was substituted for proline as a result of cytosine to thymine transfer (c.3419C>T; p. P1035L). Conclusion: Homozygosity mapping is a powerful method for finding genetic abnormalities that are both precise and comprehensive for identifying harmful variations in consanguineous families. This method is invaluable for providing accurate clinical diagnostic and genetic advice in remote regions of Pakistan while also increasing knowledge about autosomal recessive diseases and the dangers of mixing.
PubMed: 37267051
DOI: 10.7759/cureus.37933 -
Brain : a Journal of Neurology Sep 2023Moyamoya disease, a cerebrovascular disease leading to strokes in children and young adults, is characterized by progressive occlusion of the distal internal carotid...
Moyamoya disease, a cerebrovascular disease leading to strokes in children and young adults, is characterized by progressive occlusion of the distal internal carotid arteries and the formation of collateral vessels. Altered genes play a prominent role in the aetiology of moyamoya disease, but a causative gene is not identified in the majority of cases. Exome sequencing data from 151 individuals from 84 unsolved families were analysed to identify further genes for moyamoya disease, then candidate genes assessed in additional cases (150 probands). Two families had the same rare variant in ANO1, which encodes a calcium-activated chloride channel, anoctamin-1. Haplotype analyses found the families were related, and ANO1 p.Met658Val segregated with moyamoya disease in the family with an LOD score of 3.3. Six additional ANO1 rare variants were identified in moyamoya disease families. The ANO1 rare variants were assessed using patch-clamp recordings, and the majority of variants, including ANO1 p.Met658Val, displayed increased sensitivity to intracellular Ca2+. Patients harbouring these gain-of-function ANO1 variants had classic features of moyamoya disease, but also had aneurysm, stenosis and/or occlusion in the posterior circulation. Our studies support that ANO1 gain-of-function pathogenic variants predispose to moyamoya disease and are associated with unique involvement of the posterior circulation.
Topics: Child; Humans; Young Adult; Anoctamin-1; Chloride Channels; Moyamoya Disease; Neoplasm Proteins
PubMed: 37253099
DOI: 10.1093/brain/awad172 -
Analytical Sciences : the International... Sep 2023The sensitive, non-destructive constant wavelength (CW) and constant energy (CE) SFS techniques have been used for the simultaneous determination of 1-amino pyrene (AP)...
The sensitive, non-destructive constant wavelength (CW) and constant energy (CE) SFS techniques have been used for the simultaneous determination of 1-amino pyrene (AP) and 1-napthyl amine (NA) in their mixtures without prior separation via optimization of different experimental conditions (Δλ 70.0 nm, Δν 4000.0 cm, scan rate 240.0 nm/min, 25.0 °C, methanol). Amplitude-concentration plots have been linear for 1-amino pyrene, AP (0.01-0.1 mg/L) and 1-napthyl amine, NA (0.1-1.0 mg/L). In aqueous methanolic binary mixtures, the mean recoveries (RSD, LOD and LOQ) of AP were found to be 100.09% (0.053, 0.008 mg/L and 0.034 mg/L) for emission, 100.11% (0.141, 0.008 mg/L, 0.034 mg/L) for CWSFS, 100.05% (0.109, 0.007 mg/L and 0.032 mg/L) for first derivative CWSFS, 100.00% (0.148, 0.007 mg/L and 0.031 mg/L) for CESFS, 99.99% (0.109, 0.008 mg/L and 0.035 mg/L) for first derivative CESFS modes respectively. Additionally, for NA the mean recoveries (RSD, LOD and LOQ) were 100.29% (0.360, 0.046 mg/L and 0.204 mg/L) for emission, 100.06% (0.089, 0.098 mg/L, 0.436 mg/L) for CWSFS, 100.09% (0.144, 0.065 mg/L and 0.288 mg/L) for first derivative CWSFS, 100.05% (0.178, 0.077 mg/L and 0.339 mg/L) for CESFS, 100.03% (0.181, 0.082 mg/L and 0.364 mg/L) for first derivative CESFS modes respectively. Considering their safety and greenness, these methods might be considered as green tools using analytical eco-scale approaches (eco-scale score 88.0).
PubMed: 37244980
DOI: 10.1007/s44211-023-00368-8 -
Talanta Aug 2023High concentrations of inorganic arsenic in groundwater for human consumption is a worldwide common problem. Particularly, the determination of As(III) becomes...
High concentrations of inorganic arsenic in groundwater for human consumption is a worldwide common problem. Particularly, the determination of As(III) becomes important, since this species is more toxic than organic, pentavalent and elemental arsenic forms. In this work, a 3D-printed device that included a 24-well microplate was developed to perform the colourimetric kinetic determination of arsenic (III) by digital movie analysis. A smartphone camera attached to the device was used to take the movie during the process where As(III) inhibited the decolourization of methyl orange. The movie images were subsequently transformed from RGB to YIQ space to obtain a new analytical parameter called "d", which was related to the chrominance of the image. Then, this parameter allowed the determination of the inhibition time of reaction (t), which was linearly correlated with the concentration of As(III). A linear calibration curve (R = 0.9995) in the range from 5 μg L to 200 μg L was obtained. The method was precise (RSD = 1.2%), and the limits of detection (LOD) and quantification (LOQ) were 1.47 μg L and 4.44 μg L, respectively. These values were lower than the limit established by the World Health Organization for total arsenic in drinking water (10 μg L). The accuracy of the method was assessed by a recovery study with optimal results (94.3%-104.0%). Additionally, the Analytical GREEnness metric approach was applied, obtaining a score 1.7 times higher than previously published works. The method is simple, portable and low-cost, being in compliance with various principles of green analytical chemistry.
PubMed: 37201338
DOI: 10.1016/j.talanta.2023.124625 -
Frontiers in Veterinary Science 2023Near-infrared (NIR) fluorescence-guided surgery is increasingly utilized in humans and pets. As clinical imaging systems are optimized for Indocyanine green (ICG)...
INTRODUCTION
Near-infrared (NIR) fluorescence-guided surgery is increasingly utilized in humans and pets. As clinical imaging systems are optimized for Indocyanine green (ICG) detection, the usage of targeted dyes necessitates the validation of these systems for each dye. We investigated the impact of skin pigmentation and tissue overlay on the sensitivity of two NIR cameras (IC-Flow, Visionsense VS3 Iridum) for the detection of non-targeted (ICG, IRDye800) and targeted (Angiostamp, FAP-Cyan) NIR fluorophores in an big animal model.
METHODS
We quantitatively measured the limit of detection (LOD) and signal-to-background ratio (SBR) and implemented a semi-quantitative visual score to account for subjective interpretation of images by the surgeon.
RESULTS
Visionsense VS3 Iridum outperformed IC-Flow in terms of LOD and SBR for the detection of all dyes except FAP-Cyan. Median SBR was negatively affected by skin pigmentation and tissue overlay with both camera systems. Level of agreement between quantitative and semi-quantitative visual score and interobserver agreement were better with Visionsense VS3 Iridum.
CONCLUSION
The overlay of different tissue types and skin pigmentation may negatively affect the ability of the two tested camera systems to identify nanomolar concentrations of targeted-fluorescent dyes and should be considered when planning surgical applications.
PubMed: 37138917
DOI: 10.3389/fvets.2023.1091842 -
Ear and HearingA multisite clinical trial was conducted to obtain cochlear implant (CI) efficacy data in adults with asymmetric hearing loss (AHL) and establish an evidence-based...
OBJECTIVE
A multisite clinical trial was conducted to obtain cochlear implant (CI) efficacy data in adults with asymmetric hearing loss (AHL) and establish an evidence-based framework for clinical decision-making regarding CI candidacy, counseling, and assessment tools. Study hypotheses were threefold: (1) 6-month postimplant performance in the poor ear (PE) with a CI will be significantly better than preimplant performance with a hearing aid (HA), (2) 6-month postimplant performance with a CI and HA (bimodal) will be significantly better than preimplant performance with bilateral HAs (Bil HAs), and (3) 6-month postimplant bimodal performance will be significantly better than aided, better ear (BE) performance.
DESIGN
Forty adults with AHL from four, metropolitan CI centers participated. Hearing criteria for the ear to be implanted included (1) pure-tone average (PTA, 0.5, 1, 2 kHz) of >70 dB HL, (2) aided, monosyllabic word score of ≤30%, (3) duration of severe-to-profound hearing loss of ≥6 months, and (4) onset of hearing loss ≥6 years of age. Hearing criteria for the BE included (1) PTA (0.5, 1, 2, 4 kHz) of 40 to 70 dB HL, (2) currently using a HA, (3) aided, word score of >40%, and (4) stable hearing for the previous 1-year period. Speech perception and localization measures, in quiet and in noise, were administered preimplant and at 3-, 6-, 9-, and 12-months postimplant. Preimplant testing was performed in three listening conditions, PE HA, BE HA, and Bil HAs. Postimplant testing was performed in three conditions, CI, BE HA, and bimodal. Outcome factors included age at implantation and length of deafness (LOD) in the PE.
RESULTS
A hierarchical nonlinear analysis predicted significant improvement in the PE by 3 months postimplant versus preimplant for audibility and speech perception with a plateau in performance at approximately 6 months. The model predicted significant improvement in postimplant, bimodal outcomes versus preimplant outcomes (Bil HAs) for all speech perception measures by 3 months. Both age and LOD were predicted to moderate some CI and bimodal outcomes. In contrast with speech perception, localization in quiet and noise was not predicted to improve by 6 months when comparing Bil HAs (preimplant) to bimodal (postimplant) outcomes. However, when participants' preimplant everyday listening condition (BE HA or Bil HAs) was compared with bimodal performance, the model predicted significant improvement by 3 months for localization in quiet and noise. Lastly, BE HA results were stable over time; a generalized linear model analysis revealed bimodal performance was significantly better than performance with a BE HA at all postimplant intervals for most speech perception measures and localization.
CONCLUSIONS
Results revealed significant CI and bimodal benefit for AHL participants by 3-months postimplant, with a plateau in CI and bimodal performance at approximately 6-months postimplant. Results can be used to inform AHL CI candidates and to monitor postimplant performance. On the basis of this and other AHL research, clinicians should consider a CI for individuals with AHL if the PE has a PTA (0.5, 1, 2 kHz) >70 dB HL and a Consonant-Vowel Nucleus-Consonant word score ≤40%. LOD >10 years should not be a contraindication.
Topics: Adult; Humans; Cochlear Implants; Prospective Studies; Cochlear Implantation; Hearing Loss; Hearing Aids; Speech Perception; Treatment Outcome
PubMed: 37018114
DOI: 10.1097/AUD.0000000000001354 -
Experimental Eye Research May 2023Nystagmus is an ocular condition characterized by bilateral involuntary ocular oscillation which can severely affect vision. When not associated with other ocular or...
Nystagmus is an ocular condition characterized by bilateral involuntary ocular oscillation which can severely affect vision. When not associated with other ocular or systemic diseases, it is referred to as idiopathic or congenital motor nystagmus (CMN). Genome-wide linkage studies have previously identified several loci associated with CMN, however the genes responsible for some of these loci have yet to be identified. We have examined a large, five-generation family with autosomal dominant CMN. Our purpose was to characterize the clinical manifestations and reveal the molecular basis of the disease in this family. In addition to full ophthalmic examination and imaging, molecular analysis included copy number variation analysis, linkage studies, and Sanger sequencing. Expression analyses of candidate genes was done by real-time PCR. Of the 68 family members, 27 subjects in five-generations had CMN, in line with an autosomal dominant inheritance pattern. Molecular analysis was performed on 27 members, 15 of them affected by CMN. Copy number variation analysis using array comparative genomic hybridization (aCGH) revealed a novel deletion located on 1q32 (NYS7) among affected individuals. Linkage analysis using polymorphic markers demonstrated full segregation with a heterozygous haplotype in all affected patients, with a LOD score of >5. Sanger sequencing of affected subjects revealed a novel deletion of 732,526 bp in the linkage interval. No protein-coding genes exist within the deleted region; however, the deletion disrupts topologically associated domains encompassing the gene NR5A2 and the non-protein coding MIR181A. Both are strongly associated with other genes expressed in the retina such as PROX1, which in turn is also associated with genes related to nystagmus such as PAX6. We therefore hypothesized that the deletion might affect NR5A2 and MIR181A expression, causing CMN. Expression analysis by real-time PCR showed significantly lower expression of NR5A2, and significantly higher expression of PROX1 among patients compared with controls. To conclude, among a large five-generation family with autosomal dominant CMN, a large deletion in the interval of NYS7 was linked with the disease. No protein-coding genes exist inside the deleted region, and so the exact mechanism in which CMN is caused is uncertain. Based on topological association and expression analyses we suggest a possible mechanism for the pathogenesis.
Topics: Humans; Comparative Genomic Hybridization; DNA Copy Number Variations; Genetic Linkage; Inheritance Patterns; Nystagmus, Congenital; Pedigree; Chromosome Deletion
PubMed: 37001852
DOI: 10.1016/j.exer.2023.109459 -
Acta Neuropathologica Jun 2023Neuronal TDP-43-positive inclusions are neuropathological hallmark lesions in frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). Pathogenic missense...
Neuronal TDP-43-positive inclusions are neuropathological hallmark lesions in frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). Pathogenic missense variants in TARDBP, the gene encoding TDP-43, can cause ALS and cluster in the C-terminal prion-like domain (PrLD), where they modulate the liquid condensation and aggregation properties of the protein. TDP-43-positive inclusions are also found in rimmed vacuole myopathies, including sporadic inclusion body myositis, but myopathy-causing TDP-43 variants have not been reported. Using genome-wide linkage analysis and whole exome sequencing in an extended five-generation family with an autosomal dominant rimmed vacuole myopathy, we identified a conclusively linked frameshift mutation in TDP-43 producing a C-terminally altered PrLD (TDP-43) (maximum multipoint LOD-score 3.61). Patient-derived muscle biopsies showed TDP-43-positive sarcoplasmic inclusions, accumulation of autophagosomes and transcriptomes with abnormally spliced sarcomeric genes (including TTN and NEB) and increased expression of muscle regeneration genes. In vitro phase separation assays demonstrated that TDP-43 does not form liquid-like condensates and readily forms solid-like fibrils indicating increased aggregation propensity compared to wild-type TDP-43. In Drosophila TDP-43 behaved as a partial loss-of-function allele as it was able to rescue the TBPH (fly ortholog of TARDBP) neurodevelopmental lethal null phenotype while showing strongly reduced toxic gain-of-function properties upon overexpression. Accordingly, TDP-43 showed reduced toxicity in a primary rat neuron disease model. Together, these genetic, pathological, in vitro and in vivo results demonstrate that TDP-43 is an aggregation-prone partial loss-of-function variant that causes autosomal dominant vacuolar myopathy but not ALS/FTD. Our study genetically links TDP-43 proteinopathy to myodegeneration, and reveals a tissue-specific role of the PrLD in directing pathology.
Topics: Animals; Rats; Amyotrophic Lateral Sclerosis; DNA-Binding Proteins; Frameshift Mutation; Frontotemporal Dementia; Mutation; Pick Disease of the Brain; Humans
PubMed: 37000196
DOI: 10.1007/s00401-023-02565-1 -
Clinical Genetics Jun 2023Exome sequencing of genes associated with heritable thoracic aortic disease (HTAD) failed to identify a pathogenic variant in a large family with Marfan syndrome (MFS)....
Exome sequencing of genes associated with heritable thoracic aortic disease (HTAD) failed to identify a pathogenic variant in a large family with Marfan syndrome (MFS). A genome-wide linkage analysis for thoracic aortic disease identified a peak at 15q21.1, and genome sequencing identified a novel deep intronic FBN1 variant that segregated with thoracic aortic disease in the family (LOD score 2.7) and was predicted to alter splicing. RT-PCR and bulk RNA sequencing of RNA harvested from fibroblasts explanted from the affected proband revealed an insertion of a pseudoexon between exons 13 and 14 of the FBN1 transcript, predicted to lead to nonsense mediated decay (NMD). Treating the fibroblasts with an NMD inhibitor, cycloheximide, greatly improved the detection of the pseudoexon-containing transcript. Family members with the FBN1 variant had later onset aortic events and fewer MFS systemic features than typical for individuals with haploinsufficiency of FBN1. Variable penetrance of the phenotype and negative genetic testing in MFS families should raise the possibility of deep intronic FBN1 variants and the need for additional molecular studies.
Topics: Humans; Marfan Syndrome; Fibrillin-1; Mutation; Phenotype; Aortic Diseases
PubMed: 36861389
DOI: 10.1111/cge.14322