Characterization of Polyphosphoesters by Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

FT-ICR mass spectrometry, together with collision-induced dissociation and electron capture dissociation, has been used to characterize the polyphosphoester poly[1,4-bis(hydroxyethyl)terephthalate-alt-ethyloxyphosphate] and its degradation products. Three degradation pathways were elucidated: hydrolysis of the phosphate–[1,4-bis(hydroxyethyl)terephthalate]bonds; hydrolysis of the phosphate–ethoxy bonds; and hydrolysis of the ethyl–terephthalate bonds. The dominant degradation reactions were those that involved the phosphate groups. This work constitutes the first application of mass spectrometry to the characterization of polyphosphoesters and demonstrates the suitability of high mass accuracy FT-ICR mass spectrometry, with CID and ECD, for the structural analysis of polyphosphoesters and their degradation products

Genotypic and phenotypic spectrum of pyridoxine-dependent epilepsy (ALDH7A1 deficiency)

Pyridoxine-dependent epilepsy was recently shown to be due to mutations in the ALDH7A1 gene, which encodes antiquitin, an enzyme that catalyses the nicotinamide adenine dinucleotide-dependent dehydrogenation of L-{alpha}-aminoadipic semialdehyde/L-{Delta}1-piperideine 6-carboxylate. However, whilst this is a highly treatable disorder, there is general uncertainty about when to consider this diagnosis and how to test for it. This study aimed to evaluate the use of measurement of urine L-{alpha}-aminoadipic semialdehyde/creatinine ratio and mutation analysis of ALDH7A1 (antiquitin) in investigation of patients with suspected or clinically proven pyridoxine-dependent epilepsy and to characterize further the phenotypic spectrum of antiquitin deficiency. Urinary L-{alpha}-aminoadipic semialdehyde concentration was determined by liquid chromatography tandem mass spectrometry. When this was above the normal range, DNA sequencing of the ALDH7A1 gene was performed. Clinicians were asked to complete questionnaires on clinical, biochemical, magnetic resonance imaging and electroencephalography features of patients. The clinical spectrum of antiquitin deficiency extended from ventriculomegaly detected on foetal ultrasound, through abnormal foetal movements and a multisystem neonatal disorder, to the onset of seizures and autistic features after the first year of life. Our relatively large series suggested that clinical diagnosis of pyridoxine dependent epilepsy can be challenging because: (i) there may be some response to antiepileptic drugs; (ii) in infants with multisystem pathology, the response to pyridoxine may not be instant and obvious; and (iii) structural brain abnormalities may co-exist and be considered sufficient cause of epilepsy, whereas the fits may be a consequence of antiquitin deficiency and are then responsive to pyridoxine. These findings support the use of biochemical and DNA tests for antiquitin deficiency and a clinical trial of pyridoxine in infants and children with epilepsy across a broad range of clinical scenarios

Corrigendum to "European Society for Vascular Surgery (ESVS) 2022 Clinical Practice Guidelines on the Management of Chronic Venous Disease of the Lower Limbs. [Eur J Vasc Endovasc Surg (2022) 63, 184-267]"

proofepub_ahead_of_prin

The Skeletal Organic Matrix from Mediterranean Coral Balanophyllia europaea Influences Calcium Carbonate Precipitation

Scleractinian coral skeletons are made mainly of calcium carbonate in the form of aragonite. The mineral deposition occurs in a biological confined environment, but it is still a theme of discussion to what extent the calcification occurs under biological or environmental control. Hence, the shape, size and organization of skeletal crystals from the cellular level through the colony architecture, were attributed to factors as diverse as mineral supersaturation levels and organic mediation of crystal growth. The skeleton contains an intra-skeletal organic matrix (OM) of which only the water soluble component was chemically and physically characterized. In this work that OM from the skeleton of the Balanophyllia europaea, a solitary scleractinian coral endemic to the Mediterranean Sea, is studied in vitro with the aim of understanding its role in the mineralization of calcium carbonate. Mineralization of calcium carbonate was conducted by overgrowth experiments on coral skeleton and in calcium chloride solutions containing different ratios of water soluble and/or insoluble OM and of magnesium ions. The precipitates were characterized by diffractometric, spectroscopic and microscopic techniques. The results showed that both soluble and insoluble OM components influence calcium carbonate precipitation and that the effect is enhanced by their co-presence. The role of magnesium ions is also affected by the presence of the OM components. Thus, in vitro, OM influences calcium carbonate crystal morphology, aggregation and polymorphism as a function of its composition and of the content of magnesium ions in the precipitation media. This research, although does not resolve the controversy between environmental or biological control on the deposition of calcium carbonate in corals, sheds a light on the role of OM, which appears mediated by the presence of magnesium ions

Editor's Choice – European Society for Vascular Surgery (ESVS) 2022 Clinical Practice Guidelines on the Management of Chronic Venous Disease of the Lower Limbs

Corrigendum: Volume 64, Issues 2–3, 2022, 284-285Peer reviewe

Methodology for generating stable concentrations of nano-objects

With an increasing number of companies using and producing nanomaterials, also the number of workers who are exposed to nano-objects is increasing. Nano-objects, because of their very small size, can very easily overcome the human systemic barrier and rapidly penetrate into the body, settling mainly in the lungs. It is important to establish standards for nanomaterials, because of the health and safety of workers who are exposed to nanomaterials in their workplace. During the exposure evaluation, it is important to determine the parameters of nano-objects in real-time and thus it is necessary to validate the measuring apparatus used during researches. The purpose of the project is to provide the possibility of obtaining stable concentrations of the nano-objects to validate the measuring apparatus for real-time testing of parameters of the nano-objects. The literature review [1-4] on methodology for generating nano-objects using techniques of nucleation and spark discharge was made. After analyzing different models, which were found in the literature [1-4], an experimental set-up was created. The experimental set-up is composed of: an aerosol generator, an aerosol neutralizer, a high-temperature furnace, a heat exchanger, a dilution system and a sampling chamber. Our set-up has many advantages: –– it can generate different types of nano-objects (carbon, cooper and silver nano-objects) with stable concentration; –– it can generate nano-objects with different concentration; –– it allows to take four samples at the same time and measure their parameters by using various measurement apparatus. Thanks to the built set-up, it will be possible to validate measuring apparatus for testing parameters of nano-objects in real-time using an ELPI+ (Dekati) as a reference apparatus

Methods of generating nano-objects with stable concentration : literature review

Nanotechnologia jest nowoczesną dziedziną nauki, łączącą dotychczasowe osiągnięcia także innych nauk: chemii, mechaniki, biologii, fizyki oraz informatyki. Nanoobiekty, w związku z bardzo małymi wymiarami, w dosyć łatwy sposób pokonują barierę ustrojową człowieka i niestety, szybko przenikają do organizmu, osiadając przede wszystkim w płucach. W artykule dokonano przeglądu piśmiennictwa w zakresie metod generowania nanoobiektów o stabilnych stężeniach do potrzeb walidacji przyrządów pomiarowych, wykorzystywanych do badania w czasie rzeczywistym parametrów nanoobiektów. Omówiono w artykule metody generowania nanoobiektów z zastosowaniem technik nukleacji oraz wyładowania iskrowego. Wiedza na temat generowania takich cząstek może być wykorzystywana przy prognozowaniu narażenia na nanoobiekty w miejscu pracy, jak również przy projektowaniu procesów technologicznych w taki sposób, aby ograniczyć zagrożenia związane z uwalnianiem się nanoobiektów.Nanotechnology is a modern, wide field of science, which combines the achievements of chemistry, engineering, biology, physics and computer science. Unfortunately, nanoparticles, because of their small sizes in a relatively way overcame the barrier of the human systematic compartment and rapidly penetrate the body and settle mainly in lungs. This paper presents a literature review on methods of generating nano-objects with stable concentrations used for the validation of measuring devices for testing parameters of nano-objects in real-time. Methods of generating nano-objects using the techniques of nucleation and spark discharge were analyzed during the literature review. Knowledge of how to generate such particles can be used in predicting exposure to nano-objects in a workplace as well as in designing technological processes in such a way to reduce the risks connected with releasing nanoparticles