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1.
Chemosphere ; 223: 391-398, 2019 May.
Article in English | MEDLINE | ID: mdl-30797162

ABSTRACT

In this work, potassium permanganate particles (KMnO4) were modified with a manganese oxide (MnOx) shell comprising passages for the slow release of permanganate ions (MnO4-) in aquatic systems. The bare particle (KMnO4) and KMnO4 core-MnOx shell particles (CP-60) were characterized by attenuated total reflectance (ATR)-Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS). The CP-60 were evaluated as a slow source of MnO4- for the oxidative treatment of pure and lake water containing dimethyl trisulfide (DMTS), a water odorant produced by cyanobacteria in many eutrophic waters. XPS and ATR-FTIR results confirmed the presence of MnOx surface shell (diameter ∼ 1 µm) on CP-60. SEM images revealed cracks on CP-60, which serve as outlets for MnO4-. Approximately 0.76 ±â€¯0.07 g KMnO4/g of CP-60 was released from the core of CP-60 after 120 min. The CP-60 degraded 88.9 ±â€¯2.5% and 70.8 ±â€¯6.3% of DMTS in pure water and lake water matrix within 120 min, respectively. The degradation was slightly more effective than the degradation using aqueous KMnO4 (74.2%) reported in literature. The release kinetics of the particles is consistent with a pseudo-first order equation with correlation coefficients of 0.99 and 0.97 in pure water and lake water matrix, respectively. The CP could serve as low cost slow-release particles for the degradation of micropollutants, even in cyanobacteria laden water. Notably, the in situ MnOx formed during the KMnO4 oxidation reaction can facilitate adsorption of organics and metal ions, improving water quality.


Subject(s)
Manganese Compounds/pharmacology , Odorants/prevention & control , Oxides/pharmacology , Cyanobacteria , Kinetics , Lakes/chemistry , Oxidation-Reduction , Potassium Permanganate/pharmacology , Water/chemistry
2.
Clin Genet ; 87(2): 141-7, 2015 Feb.
Article in English | MEDLINE | ID: mdl-24597975

ABSTRACT

The BCAP31 gene is located between SLC6A8, associated with X-linked creatine transporter deficiency, and ABCD1, associated with X-linked adrenoleukodystrophy. Recently, loss-of-function mutations in BCAP31 were reported in association with severe developmental delay, deafness and dystonia. We characterized the break points in eight patients with deletions of SLC6A8, BCAP31 and/or ABCD1 and studied the genotype-phenotype correlations. The phenotype in patients with contiguous gene deletions involving BCAP31 overlaps with the phenotype of isolated BCAP31 deficiency. Only deletions involving both BCAP31 and ABCD1 were associated with hepatic cholestasis and death before 1 year, which might be explained by a synergistic effect. Remarkably, a patient with an isolated deletion at the 3'-end of SLC6A8 had a similar severe phenotype as seen in BCAP31 deficiency but without deafness. This might be caused by the disturbance of a regulatory element between SLC6A8 and BCAP31.


Subject(s)
ATP-Binding Cassette Transporters/genetics , Cholestasis, Intrahepatic/genetics , Intellectual Disability/genetics , Membrane Proteins/genetics , Nerve Tissue Proteins/genetics , Plasma Membrane Neurotransmitter Transport Proteins/genetics , ATP Binding Cassette Transporter, Subfamily D, Member 1 , Adrenoleukodystrophy/genetics , Adrenoleukodystrophy/mortality , Adrenoleukodystrophy/pathology , Adult , Brain Diseases, Metabolic, Inborn/genetics , Brain Diseases, Metabolic, Inborn/mortality , Brain Diseases, Metabolic, Inborn/pathology , Child , Child, Preschool , Cholestasis, Intrahepatic/mortality , Cholestasis, Intrahepatic/pathology , Creatine/deficiency , Creatine/genetics , Gene Deletion , Genetic Association Studies , Humans , Infant , Infant, Newborn , Intellectual Disability/mortality , Intellectual Disability/pathology , Male , Mental Retardation, X-Linked/genetics , Mental Retardation, X-Linked/mortality , Mental Retardation, X-Linked/pathology , Phenotype , Plasma Membrane Neurotransmitter Transport Proteins/deficiency
3.
J Med Genet ; 50(7): 463-72, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23644449

ABSTRACT

BACKGROUND: Creatine transporter deficiency is a monogenic cause of X-linked intellectual disability. Since its first description in 2001 several case reports have been published but an overview of phenotype, genotype and phenotype--genotype correlation has been lacking. METHODS: We performed a retrospective study of clinical, biochemical and molecular genetic data of 101 males with X-linked creatine transporter deficiency from 85 families with a pathogenic mutation in the creatine transporter gene (SLC6A8). RESULTS AND CONCLUSIONS: Most patients developed moderate to severe intellectual disability; mild intellectual disability was rare in adult patients. Speech language development was especially delayed but almost a third of the patients were able to speak in sentences. Besides behavioural problems and seizures, mild to moderate motor dysfunction, including extrapyramidal movement abnormalities, and gastrointestinal problems were frequent clinical features. Urinary creatine to creatinine ratio proved to be a reliable screening method besides MR spectroscopy, molecular genetic testing and creatine uptake studies, allowing definition of diagnostic guidelines. A third of patients had a de novo mutation in the SLC6A8 gene. Mothers with an affected son with a de novo mutation should be counselled about a recurrence risk in further pregnancies due to the possibility of low level somatic or germline mosaicism. Missense mutations with residual activity might be associated with a milder phenotype and large deletions extending beyond the 3' end of the SLC6A8 gene with a more severe phenotype. Evaluation of the biochemical phenotype revealed unexpected high creatine levels in cerebrospinal fluid suggesting that the brain is able to synthesise creatine and that the cerebral creatine deficiency is caused by a defect in the reuptake of creatine within the neurones.


Subject(s)
Brain Diseases, Metabolic, Inborn/genetics , Creatine/deficiency , Creatine/metabolism , Mental Retardation, X-Linked/genetics , Nerve Tissue Proteins/genetics , Plasma Membrane Neurotransmitter Transport Proteins/deficiency , Adult , Child , Creatine/genetics , Genes, X-Linked , Genetic Testing , Genotype , Humans , Male , Phenotype , Plasma Membrane Neurotransmitter Transport Proteins/genetics , Retrospective Studies
5.
J Med Genet ; 46(4): 242-8, 2009 Apr.
Article in English | MEDLINE | ID: mdl-18805830

ABSTRACT

BACKGROUND: Segmental duplications at breakpoints (BP4-BP5) of chromosome 15q13.2q13.3 mediate a recurrent genomic imbalance syndrome associated with mental retardation, epilepsy, and/or electroencephalogram (EEG) abnormalities. PATIENTS: DNA samples from 1445 unrelated patients submitted consecutively for clinical array comparative genomic hybridisation (CGH) testing at Children's Hospital Boston and DNA samples from 1441 individuals with autism from 751 families in the Autism Genetic Resource Exchange (AGRE) repository. RESULTS: We report the clinical features of five patients with a BP4-BP5 deletion, three with a BP4-BP5 duplication, and two with an overlapping but smaller duplication identified by whole genome high resolution oligonucleotide array CGH. These BP4-BP5 deletion cases exhibit minor dysmorphic features, significant expressive language deficits, and a spectrum of neuropsychiatric impairments that include autism spectrum disorder, attention deficit hyperactivity disorder, anxiety disorder, and mood disorder. Cognitive impairment varied from moderate mental retardation to normal IQ with learning disability. BP4-BP5 covers approximately 1.5 Mb (chr15:28.719-30.298 Mb) and includes six reference genes and 1 miRNA gene, while the smaller duplications cover approximately 500 kb (chr15:28.902-29.404 Mb) and contain three reference genes and one miRNA gene. The BP4-BP5 deletion and duplication events span CHRNA7, a candidate gene for seizures. However, none of these individuals reported here have epilepsy, although two have an abnormal EEG. CONCLUSIONS: The phenotype of chromosome 15q13.2q13.3 BP4-BP5 microdeletion/duplication syndrome may include features of autism spectrum disorder, a variety of neuropsychiatric disorders, and cognitive impairment. Recognition of this broader phenotype has implications for clinical diagnostic testing and efforts to understand the underlying aetiology of this syndrome.


Subject(s)
Autistic Disorder/genetics , Chromosome Aberrations , Chromosomes, Human, Pair 15/genetics , Intellectual Disability/genetics , Adolescent , Autistic Disorder/pathology , Child , Child, Preschool , Chromosome Deletion , Comparative Genomic Hybridization , Female , Gene Duplication , Humans , Infant , Intellectual Disability/pathology , Male , Phenotype , Young Adult
6.
J Inherit Metab Dis ; 29(1): 214-9, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16601897

ABSTRACT

We report two unrelated boys with the X-linked creatine transporter defect (CRTR) and clinical features more severe than those previously described with this disorder. These two boys presented at ages 12 and 30 months with severe mental retardation, absent speech development, hypotonia, myopathy and extra-pyramidal movement disorder. One boy has seizures and some dysmorphic features; he also has evidence of an oxidative phosphorylation defect. They both had classical absence of creatine peak on brain magnetic resonance spectroscopy (MRS). In one, however, this critical finding was overlooked in the initial interpretation and was discovered upon subsequent review of the MRS. Molecular studies showed large genomic deletions of a large part of the 3' end of the complete open reading frame of the SLC6A8 gene. This report emphasizes the importance of MRS in evaluating neurological symptoms, broadens the phenotypic spectrum of CRTR and adds knowledge about the pathogenesis of creatine depletion in the brain and retina.


Subject(s)
Chromosomes, Human, X , Membrane Transport Proteins/deficiency , Membrane Transport Proteins/genetics , Metabolism, Inborn Errors/genetics , Child, Preschool , Eye/pathology , Gene Deletion , Humans , Infant , Intellectual Disability/diagnosis , Intellectual Disability/genetics , Magnetic Resonance Spectroscopy , Male , Metabolism, Inborn Errors/diagnosis , Nerve Tissue Proteins/genetics , Oxygen/metabolism , Phenotype , Phosphorylation , Plasma Membrane Neurotransmitter Transport Proteins/genetics
7.
J Child Neurol ; 16(3): 212-5, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11305689

ABSTRACT

Progeria, a rare genetic disorder, is characterized by severe growth failure, premature aging, and very early atherosclerosis with coronary artery and cerebrovascular disease. There has been no detailed description of progressive cerebrovascular changes in progeria or any attempted neurologic correlation of those changes. A 5-year-old boy developed signs of progeria at 4 months and hypertension at 4 years, treated with atenolol and dipyridamole. Left-sided seizures with a left hemiparesis occurred at 5 years. Magnetic resonance imaging (MRI) showed bilateral acute, subacute, and chronic cerebral infarctions. Magnetic resonance angiography disclosed severe stenosis of the left internal carotid artery. The child was also found to have an aortic valve vegetation and was anticoagulated. He subsequently developed right-sided seizures, and treatment with gabapentin was started. Later, severe stenosis also of the right internal carotid artery was found. MRI showed new left cerebral infarction. The child's neurologic symptoms almost certainly were caused by cerebral infarctions from progressive atherosclerosis of major intracranial vessels, but clinical-neuroradiologic correlations were imprecise. There were multiple cerebral infarctions of different ages, some asymptomatic, others ipsilateral to the child's neurologic findings. No therapy has halted progression of the child's cerebrovascular disease.


Subject(s)
Carotid Stenosis/diagnosis , Cerebral Infarction/diagnosis , Epilepsies, Partial/diagnosis , Progeria/diagnosis , Brain/pathology , Carotid Artery, Internal/pathology , Carotid Stenosis/genetics , Cerebral Infarction/genetics , Epilepsies, Partial/genetics , Humans , Intracranial Arteriosclerosis/diagnosis , Intracranial Arteriosclerosis/genetics , Magnetic Resonance Angiography , Magnetic Resonance Imaging , Male , Progeria/genetics
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