21 research outputs found

    Palynological investigation of a Late Quaternary calcareous tufa and travertine deposit: the case study of Bagnoli in the Valdelsa Basin (Tuscany, central Italy)

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    A Late Quaternary continental succession in central Italy (Bagnoli, Valdelsa Basin)which includes terrigenous and carbonate (calcareous tufa and travertine) sedimentswas investigated with palynology, 14C dating and stable isotopic techniques. Pollen analyses of 43 samples, including quantification by the Climate Amplitude Method, allowed the documentation of the main palaeoenvironmental, vegetational and climatic changes. Taphonomic biases related to the depositional settings are expressed by i) the significant occurrence of Pinus related to the increase of riverine input/waterborne pollen components in the basal terrigenous strata and by ii) the generally significant presence of herbs, testimony to the local pollen input and dominance of the airborne pollen component in calcareous tufa and travertine. 14C dating on organic samples confirms the Late Quaternary age of the section and the pollen record supports evidence for the onset of carbonate deposition during the Late Glacial Interstadial (LGI), coincident with expansion of thermophilous tree taxa, especially deciduous oaks. Successive cool and dry climate events are attested by the contemporaneous decrease of broad leaved deciduous forest taxa and a rise in herbs. Major unconformities aswell as erosional, non-depositional or dissolution events,which interrupt the carbonate deposition at different times in the sequence, are interpreted as a direct response to global climate change and associated to cooler events (i.e. GS-2, GS-1, colder episodes during the LGI). As awhole ÎŽ13C andÎŽ18O records do not show any clear relationship to the pollen-derived climatic data or to the carbonate units; rather they reflect a mixing of superficial CO2 and a deeper source, underlining the complex origin of the Bagnoli carbonates

    Abatement of 2,4-D by H2O2 solar photolysis and solar photo-Fenton-like process with minute Fe(III) concentrations

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    The Photo-Fenton-like (PF-like) process with minute Fe(III) concentrations and the Hydrogen Peroxide Photolysis (HPP), using Xe-lamp or solar light as sources of irradiation, were efficiently applied to eliminate the herbicide 2,4-D from water. PF-like experiments concerning ferric and H2O2 concentrations of 0.6 mg L−1 and 20 mg L−1 respectively, using Xenon lamps (Xe-lamps) as a source of irradiation and 2,4-D concentrations of 10 mg L−1 at pH 3.6, exhibited complete 2,4-D degradation and 77% dissolved organic carbon (DOC) removal after 30 min and 6 h of irradiation respectively whereas HPP (in absence of ferric ions) experiments showed a 2,4-D reduction and DOC removal of 90% and 7% respectively after 6 h of irradiation. At pH 7.0, HPP process achieved a 2,4-D abatement of approximately 75% and a DOC removal of 4% after 6 h. PF-like exhibited slightly improved 2,4-D and DOC removals (80% and 12% respectively) after the same irradiation time probably due to the low pH reduction (from 7.0 to 5.6). Several chlorinated-aromatic intermediates were identified by HPLC-MS. These by-products were efficiently removed by PF at pH 3.6, whereas at neutral PF-like and acid or neutral HPP, they were not efficiently degraded. With natural solar light irradiation, 10 and 1 mg L−1 of 2,4-D were abated using minor H2O2 concentrations (3, 6, 10 and 20 mg L−1) and iron at 0.6 mg L−1 in Milli-Q water. Similar results to Xe-lamp experiments were obtained, where solar UV-B + A light H2O2 photolysis (HPSP) and solar photo-Fenton-like (SPF-like) played an important role and even at low H2O2 and ferric concentrations of 3 and 0.6 mg L−1 respectively, 2,4-D was efficiently removed at pH 3.6. Simulated surface water at pH 3.6 containing 1 mg L−1 2,4-D, 20 mg L−1 H2O2 and 0.6 mg L−1 Fe(III) under natural sunlight irradiation efficiently removed the herbicide and its main metabolite 2,4-DCP after 30 min of treatment while at neutral pH, 40% of herbicide degradation was achieved. In the case of very low iron concentrations (0.05 mg L−1) at acid pH, 150 min of solar treatment was required to remove 2,4-D.Fil: Serra Clusellas, Anna. Instituto TecnolĂłgico de Buenos Aires. Departamento de IngenierĂ­a QuĂ­mica; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; ArgentinaFil: De Angelis, Laura. Instituto TecnolĂłgico de Buenos Aires. Departamento de IngenierĂ­a QuĂ­mica; ArgentinaFil: Lin, Chung Ho. University of Missouri; Estados UnidosFil: Vo, Phuc. University of Missouri; Estados UnidosFil: Bayati, Mohamed. University of Missouri; Estados UnidosFil: Sumner, Lloyd. University of Missouri; Estados UnidosFil: Lei, Zhentian. University of Missouri; Estados UnidosFil: Amaral, Nathalia B.. Centro Federal de EducacĂŁo TecnolĂłgica de Minas Gerais; BrasilFil: Bertini, Liliana M.. Instituto TecnolĂłgico de Buenos Aires. Departamento de IngenierĂ­a QuĂ­mica; ArgentinaFil: Mazza, Jose. Instituto TecnolĂłgico de Buenos Aires. Departamento de IngenierĂ­a QuĂ­mica; ArgentinaFil: Pizzio, Luis Rene. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - La Plata. Centro de InvestigaciĂłn y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de InvestigaciĂłn y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Stripeikis, Jorge Daniel. Instituto TecnolĂłgico de Buenos Aires. Departamento de IngenierĂ­a QuĂ­mica; ArgentinaFil: Rengifo Herrera, Julian Andres. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - La Plata. Centro de InvestigaciĂłn y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de InvestigaciĂłn y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Fidalgo de Cortalezzi, Maria M.. Instituto TecnolĂłgico de Buenos Aires. Departamento de IngenierĂ­a QuĂ­mica; Argentin

    UFM1 founder mutation in the Roma population causes recessive variant of H-ABC

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    Objective: To identify the gene defect in patients with hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC) who are negative for TUBB4A mutations. Methods: We performed homozygosity mapping and whole exome sequencing (WES) to detect the disease-causing variant. We used a Taqman assay for population screening. We developed a luciferase reporter construct to investigate the effect of the promoter mutation on expression. Results: Sixteen patients from 14 families from different countries fulfilling the MRI criteria for H-ABC exhibited a similar, severe clinical phenotype, including lack of development and a severe epileptic encephalopathy. The majority of patients had a known Roma ethnic background. Single nucleotide polymorphism array analysis in 5 patients identified one large overlapping homozygous region on chromosome 13. WES in 2 patients revealed a homozygous deletion in the promoter region of UFM1. Sanger sequencing confirmed homozygosity for this variant in all 16 patients. All patients shared a common haplotype, indicative of a founder effect. Screening of 1,000 controls from different European Roma panels demonstrated an overall carrier rate of the mutation of 3%–25%. Transfection assays showed that the deletion significantly reduced expression in specific CNS cell lines. Conclusions: UFM1 encodes ubiquitin-fold modifier 1 (UFM1), a member of the ubiquitin-like family involved in posttranslational modification of proteins. Its exact biological role is unclear. This study associates a UFM1 gene defect with a disease and sheds new light on possible UFM1 functional networks

    Bi-allelic LETM1 variants perturb mitochondrial ion homeostasis leading to a clinical spectrum with predominant nervous system involvement

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    Leucine zipper-EF-hand containing transmembrane protein 1 (LETM1) encodes an inner mitochondrial membrane protein with an osmoregulatory function controlling mitochondrial volume and ion homeostasis. The putative association of LETM1 with a human disease was initially suggested in Wolf-Hirschhorn syndrome, a disorder that results from de novo monoallelic deletion of chromosome 4p16.3, a region encompassing LETM1. Utilizing exome sequencing and international gene-matching efforts, we have identified 18 affected individuals from 11 unrelated families harboring ultra-rare bi-allelic missense and loss-of-function LETM1 variants and clinical presentations highly suggestive of mitochondrial disease. These manifested as a spectrum of predominantly infantile-onset (14/18, 78%) and variably progressive neurological, metabolic, and dysmorphic symptoms, plus multiple organ dysfunction associated with neurodegeneration. The common features included respiratory chain complex deficiencies (100%), global developmental delay (94%), optic atrophy (83%), sensorineural hearing loss (78%), and cerebellar ataxia (78%) followed by epilepsy (67%), spasticity (53%), and myopathy (50%). Other features included bilateral cataracts (42%), cardiomyopathy (36%), and diabetes (27%). To better understand the pathogenic mechanism of the identified LETM1 variants, we performed biochemical and morphological studies on mitochondrial K+/H+ exchange activity, proteins, and shape in proband-derived fibroblasts and muscles and in Saccharomyces cerevisiae, which is an important model organism for mitochondrial osmotic regulation. Our results demonstrate that bi-allelic LETM1 variants are associated with defective mitochondrial K+ efflux, swollen mitochondrial matrix structures, and loss of important mitochondrial oxidative phosphorylation protein components, thus highlighting the implication of perturbed mitochondrial osmoregulation caused by LETM1 variants in neurological and mitochondrial pathologies.This research was supported using resources of the Core Facility Cell Imaging and Ultrastructure Research, University of Vienna, a member of the Vienna Life-Science Instruments (VLSI) and the VetCore Facility (Imaging) of the University of Veterinary Medicine Vienna. We acknowledge International Centre for Genomic Medicine in Neuromuscular Diseases. This research was funded in part, by the Wellcome Trust (WT093205MA, WT104033AIA, and the Synaptopathies Strategic Award, 165908). This study was funded by the Medical Research Council (MR/S01165X/1, MR/S005021/1, G0601943), The National Institute for Health Research University College London Hospitals Biomedical Research Centre, Rosetrees Trust, Ataxia UK, Multiple System Atrophy Trust, Brain Research United Kingdom, Sparks Great Ormond Street Hospital Charity, Muscular Dystrophy United Kingdom (MDUK), Muscular Dystrophy Association (MDA USA) and Senior Non-Clinical Fellow ship to A. Spinazzola, (MC_PC_13029). K.N. and S.E.M.M. were supported by the Austrian Science Funds FWF-P29077 and P31471. A. Spinazzola receives support also from The Lily Foun dation and Brain Research UK. R.K. was supported by European Academy of Neurology Research Training Fellowship and Rosetrees Trust PhD Plus award (PhD2022\100042).info:eu-repo/semantics/publishedVersio
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