Iodide ion-imprinted chitosan beads for highly selective adsorption for nuclear wastewater treatment applications.

Iodide ions from radioactive iodine isotopes are common contaminants present in nuclear wastewater from nuclear power plants which are considered hazardous contaminants to be released in water sources even at low concentrations due to their association with metabolic disorders, therefore its removal from the nuclear wastewater effluents is necessary. Chitosan beads are natural and cost-efficient adsorbents that have been used for ion removal from wastewater. However, issues of poor selectivity persist in achieving high-efficiency iodide ion removal. In this study, ion-imprinted chitosan beads (IIC) have been synthesized using the phase-inversion method, IIC beads were modified by cross-linking with epichlorohydrin (IIC-EPI) and modified by cross-linking with epichlorohydrin and silicon dioxide nanoparticles (IIC-SiO2-EPI). Through 4 h of batch adsorption experiments, IIC beads achieved a maximum adsorption capacity (Qe) of 0.65 mmol g-1 and showed more preference for the iodide ions compared to the non-imprinted chitosan beads which achieved a maximum adsorption capacity of 0.27 mmol g-1 at pH 7. While the modified beads IIC-EPI and IIC-SiO2-EPI beads have boosted the adsorption capacities to 0.72 mmol g-1 and 0.91 mmol g-1. Scanning electron microscopic cross-sectional images have shown more pores and cavities than the surface images which agrees with the multilayer heterogeneous diffusion suggested by the Freundlich adsorption isotherm, that the experimental data has fitted. Adsorption kinetic data have fitted the Pseudo-second-order model as well as the Weber and Morris intraparticle model, which suggest an intraparticle pore diffusion adsorption mechanism, with the involvement of the physical electrostatic interactions with the cationic chitosan surface.

Further delineation of Wiedemann-Rautenstrauch syndrome linked with POLR3A.

Wiedemann-Rautenstrauch Syndrome (WRS; MIM 264090) is an extremely rare and highly heterogeneous syndrome that is inherited in a recessive fashion. The patients have hallmark features such as prenatal and postnatal growth retardation, short stature, a progeroid appearance, hypotonia, facial dysmorphology, hypomyelination leukodystrophy, and mental impairment. Biallelic disease-causing variants in the RNA polymerase III subunit A (POLR3A) have been associated with WRS. Here, we report the first identified cases of WRS syndrome with novel phenotypes in three consanguineous families (two Omani and one Saudi) characterized by biallelic variants in POLR3A. Using whole-exome sequencing, we identified one novel homozygous missense variant (NM_007055: c.2456C>T; p. Pro819Leu) in two Omani families and one novel homozygous variant (c.1895G>T; p Cys632Phe) in Saudi family that segregates with the disease in the POLR3A gene. In silico homology modeling of wild-type and mutated proteins revealed a substantial change in the structure and stability of both proteins, demonstrating a possible effect on function. By identifying the homozygous variants in the exon 14 and 18 of the POLR3A gene, our findings will contribute to a better understanding of the phenotype-genotype relationship and molecular etiology of WRS syndrome.

Upwelling and nutrient dynamics in the Arabian Gulf and sea of Oman.

This study demonstrates the vertical and horizontal distribution of nutrients and the seasonal response of nutrients to upwelling in the Arabian Gulf and the Sea of Oman. Thus, monthly data on nitrate, phosphate, and silicate are obtained from the World Ocean Atlas 2018 (WOA), as well as estimates of coastal and curl driven upwelling in both regions. The results of the study indicate that the Sea of Oman's surface and deep waters contained higher concentrations of nutrients than the Arabian Gulf by 80%. In addition, both regions have exhibited a general increase in the vertical distribution of nutrients as the depth increases. Among the aforementioned nutrients, nitrate is found to be a more limiting nutrient for phytoplankton growth than phosphate as the nitrate-to-phosphate ratios (N:P) in surface waters are lower (≤ 4.6:1) than the Redfield ratio (16:1). As for the upwelling, curl-driven upwelling accounts for more than half of the total upwelling in both regions, and both play an important role in nutrient transport. Thus, nutrients are upwelled from the subsurface to the mixed layer at a rate of 50% in the Oman Sea from 140 m to 20 m during the summer and to 40 m during the winter. Similarly, the Arabian Gulf shows 50% transport for nitrates, but 32% for phosphates, from 20 m to 5-10 m. However, due to the abundance of diatoms at the surface of the Arabian Gulf, the surface silicate content is 30% higher than that of the deeper waters.

Uptake of prenatal genetic diagnosis and termination of pregnancy by Omani Muslim families at risk of genetic disorders: experience over a 9-year period.

Studies on the acceptance of prenatal diagnosis and termination of pregnancy for single gene disorders within Islamic societies in the Middle East are limited. A few have examined the attitudes toward pregnancy termination for fetal indications, but a dearth of published data exists on actual behavior and uptake. This study reports on all prenatal diagnosis requests for single gene disorders, from the Sultanate of Oman, over 9 years. A retrospective study was conducted during which the medical records of all women who performed prenatal diagnoses for single gene disorders were reviewed. A total of 148 invasive procedures were performed for 114 families. The total number of yearly requests for prenatal diagnosis increased exponentially from three in 2012 to 21 in 2020. Sixty-four different diagnoses were tested for with the majority being autosomal recessive in nature. Seventy-one percent (28/39) of cases where an affected pregnancy was identified were terminated. Fifty-two of the 114 women (45.6%) repeated prenatal diagnosis in a future pregnancy. Seventy-two couples (63%) were consanguineous parents related as second cousins or closer. The majority of tests performed were for couples from Muscat (27%), Albatinah (27%), and Alsharqiya (20.3%) governorates in Oman. The findings of this study provide evidence that prenatal diagnosis is an acceptable reproductive option to prevent the occurrence of genetic disorders that meet termination eligibility criteria as outlined by the Islamic Jurisprudence (Fiqh) Council Fatwa, among Omani Muslim couples.

A disorder clinically resembling cystic fibrosis caused by biallelic variants in the AGR2 gene.

PURPOSE: We sought to describe a disorder clinically mimicking cystic fibrosis (CF) and to elucidate its genetic cause. METHODS: Exome/genome sequencing and human phenotype ontology data of nearly 40 000 patients from our Bio/Databank were analysed. RNA sequencing of samples from the nasal mucosa from patients, carriers and controls followed by transcriptome analysis was performed. RESULTS: We identified 13 patients from 9 families with a CF-like phenotype consisting of recurrent lower respiratory infections (13/13), failure to thrive (13/13) and chronic diarrhoea (8/13), with high morbidity and mortality. All patients had biallelic variants in AGR2, (1) two splice-site variants, (2) gene deletion and (3) three missense variants. We confirmed aberrant AGR2 transcripts caused by an intronic variant and complete absence of AGR2 transcripts caused by the large gene deletion, resulting in loss of function (LoF). Furthermore, transcriptome analysis identified significant downregulation of components of the mucociliary machinery (intraciliary transport, cilium organisation), as well as upregulation of immune processes. CONCLUSION: We describe a previously unrecognised autosomal recessive disorder caused by AGR2 variants. AGR2-related disease should be considered as a differential diagnosis in patients presenting a CF-like phenotype. This has implications for the molecular diagnosis and management of these patients. AGR2 LoF is likely the disease mechanism, with consequent impairment of the mucociliary defence machinery. Future studies should aim to establish a better understanding of the disease pathophysiology and to identify potential drug targets.

A novel POC1A variant in an alternatively spliced exon causes classic SOFT syndrome: clinical presentation of seven patients.

Biallelic pathogenic variants in POC1A are ultra rare. They have been reported in 13 families as causing either Short stature, Onychodysplasia, Facial dysmorphism, and hypoTrichosis (SOFT) syndrome, or a milder partially overlapping phenotype, variant POC1A-related syndrome. This pleiotropic effect is likely precipitated by the variant's location and respective affected protein domain. Here, we describe seven patients from two consanguineous Omani families with classic SOFT syndrome and a novel homozygous POC1A variant (c.64G>T; p.(Val22Phe)), which is the first one described for the alternative exon 2. This result refines the POC1A mutational spectrum relevant for exertion of the described pleiotropic effect. Furthermore, six of our patients experienced recurrent mild to severe respiratory difficulties that have not been previously reported for SOFT syndrome and may be an underdiagnosed or a genotype-specific complication that warrants attention in future studies. Thus, our study unravels new aspects of the genotype-phenotype correlation suggested by previous reports.

Myocarditis as a lupus challenge: two case reports.

BACKGROUND: Myocarditis is an uncommon manifestation of systemic lupus erythematosus in which the clinical presentation can range from subclinical to life-threatening. We report cases of two patients who presented to our hospital with myocarditis as an initial manifestation of systemic lupus erythematosus despite negative results of extensive workup that excluded other diagnoses. The mainstays of treatment are corticosteroids, immunosuppressive agents, and anti-heart failure medications, with use of the latter being case-specific. Mycophenolate mofetil was the cornerstone of the proposed treatment for induction of remission, although it is well known to be used as a maintenance therapy in lupus myocarditis. CASE PRESENTATION: Both Emirati patients described satisfied the diagnostic criteria for mixed connective tissue disease (systemic lupus predominant) and systemic lupus erythematous. Other differential diagnoses of myocarditis were excluded. The patients were started on pulsed steroid followed by oral steroid, with hydroxychloroquine, mycophenolate mofetil, and anti-heart failure medications used as needed. Dramatic responses were noted in the first few weeks in terms of symptoms. CONCLUSION: Early recognition and treatment of lupus myocarditis is needed to avoid fatal consequences.

Pallister-Killian Mosaic Syndrome in an Omani Newborn: A Case Report and Literature Review.

Pallister-Killian mosaic syndrome (PKS) is a rare sporadic condition with multiple congenital anomalies and intellectual deficits caused by mosaic tissue-limited tetrasomy of the short arm of chromosome 12 (12p). The clinical features are highly variable, ranging from mild to severe. Diagnosis is usually missed because of the low level of mosaicism in peripheral lymphocytes. We present a case of an Omani newborn with PKS with severe clinical presentation and multisystem involvement that lead to postnatal death. Karyotype and fluorescent in situ hybridization studies confirmed the presence of chromosome 12p duplication. This is the first case of PKS reported in the literature from Oman and the Arab world.

Towards establishing consistency in triage in a tertiary specialty.

Clinical Genetics services provide a diagnostic, counselling and genetic testing service for children and adults affected by, or at risk of, a genetic condition, most of which are rare, and/or genetically heterogeneous. Appropriate triage of referrals is crucial to ensure that the most urgent referrals are seen as quickly as possible, without negatively impacting the waiting times of less urgent cases. We aimed to examine triage practice in six Clinical Genetic centres across the United Kingdom and Ireland. Thirteen simulated referrals were drafted based on common referrals to Clinical Genetics. Copies of each referral were forwarded to each centre, where 10 nominated clinicians were asked to triage each referral. Triaged referrals were returned to the coordinating author for analysis. An electronic questionnaire was contemporaneously completed by clinical leads in each unit to gather local demographic details and local operating procedures relevant to triage. Widespread inconsistencies were noted both within and between units, with respect to the acceptance of referrals to the services, prioritisation and designated clinic type. Referral rates, staffing levels and waiting lists varied widely between units. Inconsistencies observed between units are likely influenced by a number of factors, including staffing levels, referral rates and average family size. Inconsistency within units likely reflects the complex nature of many Clinical Genetic referrals, and triage guidelines should help improve decision-making in this setting.

NRXN1 deletion syndrome; phenotypic and penetrance data from 34 families.

The spectrum of phenotypes associated with heterozygous deletions of neurexin-1 (NRXN1) is diverse and includes: autism spectrum disorder, attention deficit hyperactivity disorder, intellectual disability, seizures, schizophrenia, mood disorders and congenital malformations. Reduced penetrance and variable expressivity of deletions in this gene remain a challenge for genetic counselling. We clinically reviewed 67 NRXN1 deletions from 34 families to document the phenotype and determine odds ratio. Thirty-four probands (5 adults, 29 children (<16 years)) were initially identified from a cohort clinically referred for arrayCGH. A further 33 NRXN1 deletions (16 with established phenotype) from the families were identified following cascade screening. Speech and language delay was a consistent clinical presentation. Pedigree analysis of the inherited group revealed numerous untested relatives with a history of mental health and developmental issues, most notably in the NRXN1ß isoform patients. Our study highlights the complex nature of the NRXN1 phenotype in this population.

In situ spectral response of the Arabian Gulf and Sea of Oman coastal waters to bio-optical properties.

Mapping of Chlorophyll-a (Chl-a) over the coastal waters of the Arabian Gulf and the Sea of Oman using the satellite-based observations, such as MODIS (Moderate Resolution Imaging Spectro-radiometer), has shown inferior performance (Chl-a overestimation) than that of deep waters. Studies in the region have shown that this poor performance is due to three reasons: (i) water turbidity (sediments re-suspension), and the presence of colored dissolved organic matter (CDOM), (ii) bottom reflectance and (iii) incapability of the existing atmospheric correction models to reduce the effect of the aerosols from the water leaving radiance. Therefore, this work focuses on investigating the sensitivity of the in situ spectral signatures of these coastal waters to the algal (chlorophyll: Chl-a), non-algal (sediments and CDOM) and the bottom reflectance properties, in absence of contributions from the atmosphere. Consequently, the collected in situ spectral signatures will improve our understanding of Arabian Gulf and Sea of Oman water properties. For this purpose, comprehensive field measurements were carried out between 2013 and 2016, over Abu-Dhabi (Arabian Gulf) and Fujairah (Sea of Oman) where unique water quality data were collected. Based on the in situ water spectral analysis, the bottom reflectance (water depth<20m) are found to degrade the performance of the conventional ocean color algorithms more than the sediment-laden waters where these waters increase the Rrsat the blue and red ranges. The increasing presence of CDOM markedly decreases the Rrsin the blue range, which is conflicting with the effect of Chl-a. Given the inadequate performance of the widely used ocean-color algorithms (OC3: ocean color 3, OC2: ocean color 2) in retrieving Chl-a in these very shallow coastal waters, therefore, a new algorithm is proposed here based on a 3-bands ratio approach using [Rrs (656) -1-Rrs (506) -1]×Rrs (661). The selected optimum bands (656nm, 506nm, and 661nm) from this approach can be used to retrieve the Chl-a more accurately in these coastal Case II (turbid) waters which are close to the bands of the current missions such as Sentinel-3 OLCI (Ocean and Land Colour Instrument), MODIS, VIIRS (Visible Infrared Imaging Radiometer Suite) and LandSat 8. However, more uniformly distributed data over the Arabian Gulf is required to have a highly accurate regional model for Chl-a retrieval.

Rubinstein-Taybi syndrome type 2: report of nine new cases that extend the phenotypic and genotypic spectrum.

Rubinstein-Taybi syndrome (RTS) is an autosomal dominant neurodevelopmental disorder characterized by growth deficiency, broad thumbs and great toes, intellectual disability and characteristic craniofacial appearance. Mutations in CREBBP account for around 55% of cases, with a further 8% attributed to the paralogous gene EP300. Comparatively few reports exist describing the phenotype of Rubinstein-Taybi because of EP300 mutations. Clinical and genetic data were obtained from nine patients from the UK and Ireland with pathogenic EP300 mutations, identified either by targeted testing or by exome sequencing. All patients had mild or moderate intellectual impairment. Behavioural or social difficulties were noted in eight patients, including three with autistic spectrum disorders. Typical dysmorphic features of Rubinstein-Taybi were only variably present. Additional observations include maternal pre-eclampsia (2/9), syndactyly (3/9), feeding or swallowing issues (3/9), delayed bone age (2/9) and scoliosis (2/9). Six patients had truncating mutations in EP300, with pathogenic missense mutations identified in the remaining three. The findings support previous observations that microcephaly, maternal pre-eclampsia, mild growth restriction and a mild to moderate intellectual disability are key pointers to the diagnosis of EP300-related RTS. Variability in the presence of typical facial features of Rubinstein-Taybi further highlights clinical heterogeneity, particularly among patients identified by exome sequencing. Features that overlap with Floating-Harbor syndrome, including craniofacial dysmorphism and delayed osseous maturation, were observed in three patients. Previous reports have only described mutations predicted to cause haploinsufficiency of EP300, whereas this cohort includes the first described pathogenic missense mutations in EP300.

Analysis of the spatio-temporal variability of seawater quality in the southeastern Arabian Gulf.

In this study, seawater quality measurements, including salinity, sea surface temperature (SST), chlorophyll-a (Chl-a), Secchi disk depth (SDD), pH, and dissolved oxygen (DO), were made from June 2013 to November 2014 at 52 stations in the southeastern Arabian Gulf. Significant variability was noticed for all collected parameters. Salinity showed a decreasing trend, and Chl-a, DO, pH, and SDD demonstrated increasing trends from shallow onshore stations to deep offshore ones, which could be attributed to variations of ocean circulation and meteorological conditions from onshore to offshore waters, and the likely effects of desalination plants along the coast. Salinity and temperature were high in summer and low in winter while Chl-a, SDD, pH, and DO indicated an opposite trend. The CTD profiles showed vertically well-mixed structures. Qualitative analysis of phytoplankton showed a high diversity of species without anomalous species found except in Ras Al Khaimah stations where diatoms were the dominating ones.

An overview of historical harmful algae blooms outbreaks in the Arabian Seas.

Harmful algae blooms (HABs), often composed of oceanic plants called phytoplankton, are potentially harmful to the marine life, water quality, human health, and desalination plants, a chief source of potable water in the Arabian Gulf. The last decade has seen a noticeable increase in the frequency of HAB outbreaks in the Arabian Seas. This increase is mainly caused by the unprecedented economic growth in the region. The increased human activities in the region have added more stress to the marine environment and contributed to the changes observed in the properties of the marine ecosystem: high temperature and salinity, high evaporation rates, limited freshwater inflow, shallow nature, pollution. However, very few studies that cover the HAB outbreaks, causes, impacts and biological characteristics over the region have been published. This work presents a comprehensive overview of historical HAB outbreaks recorded in the region, and investigate their causes and impact, and seasonal variability.