Publications by authors named "Konstantinova M"

Glycerol-(9,10-trioxolane) trioleate (OTOA) is a promising material that combines good plasticizing properties for PLA with profound antimicrobial activity, which makes it suitable for application in state-of-the-art biomedical and packaging materials with added functionality. On the other hand, application of OTOA in PLA-based antibacterial materials is hindered by a lack of knowledge on kinetics of the OTOA release. In this work, the release of glycero-(9,10-trioxolane) trioleate (OTOA) from PLA films with 50% OTOA content was studied during incubation in normal saline solution, and for the first time, the kinetics of OTOA release from PLA film was evaluated.

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The product of ozonolysis, glycero-(9,10-trioxolane)-trioleate (ozonide of oleic acid triglyceride, [OTOA]), was incorporated into polylactic acid/polycaprolactone (PLA/PCL) blend films in the amount of 1, 5, 10, 20, 30 and 40% /. The morphological, mechanical, thermal and antibacterial properties of the biodegradable PLA/PCL films after the OTOA addition were studied. According to DSC and XRD data, the degree of crystallinity of the PLA/PCL + OTOA films showed a general decreasing trend with an increase in OTOA content.

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The shapes of the deep slope (below the maximum values) of the vertical profiles of radiocesium activity concentrations in the sediment samples taken in 2003-2012 in the Lakes Juodis, Tapeliai and Red lake were studied. The Gaussian shape of the deep slope indicates the migration of radiocesium into the depths of the sediments, and this process is significantly enhanced in some places due to bioturbation caused by tench preparing for hibernation. The exponential shape of the deep slope is typical for sediments in which in winter, in the presence of an ice cover on the lake, thermodynamic mixing occurs in the surface layer caused by the effects of pore water buoyancy.

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Glycero-(9,10-trioxolane)-trioleate (ozonide of oleic acid triglyceride, OTOA) was introduced into polylactic acid (PLA) films in amounts of 5, 10, 30, 50, and 70% /. The morphological, mechanical, thermal, and water absorption properties of PLA films after the OTOA addition were studied. The morphological analysis of the films showed that the addition of OTOA increased the diameter of PLA spherulites and, as a consequence, increased the proportion of amorphous regions in PLA films.

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Childhood obesity is assuredly one of the most important health challenges of the 21st century, particularly regarding long-term metabolic complications. In the last four decades, there has been a tenfold increase in childhood and adolescence obesity. This cross-sectional study aimed to show the prevalence of overweight and obesity compared by age, sex, and ethnicity in n=1034 healthy male and female children, aged 6-13 years in North Macedonia.

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In this study, two types of biosorbents were used to remove Cs and plutonium isotopes from aqueous solutions - moss (Ptilium crista - castrensis) and oak sawdust (Quercus robur), both in the form of natural and modified state. Sorbent modification significantly increases the sorbent surface area (for moss sorbents - from 4.0 to 47.

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Biocompatible glycero (9,10-trioxolane) trioleate (ozonide of oleic acid triglyceride, OTOA) was incorporated into polylactic acid (PLA) fibers by electrospinning and nonwoven PLA mats with 1%, 3% and 5% OTOA content. The morphological, mechanical, thermal and water sorption properties of electrospun PLA mats after the addition of OTOA were studied. A morphological analysis showed that the addition of OTOA increased the average fiber diameter and induced the formation of pores on the fiber surface, leading to an increase in the specific surface area for OTOA-modified PLA fibrous mats.

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The therapeutic landscape of human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (mBC) has evolved considerably with the introduction of newer targeted agents such as poly-ADP ribose polymerase inhibitors (PARPi), novel chemotherapeutic agents, immunotherapy, and endocrine therapies. In this scenario, optimizing the appropriate treatment sequence is a daunting task for clinicians. To develop evidence-based answers to key clinical questions on treatment selection and appropriate treatment sequence for the management of patients with HER2- mBC in the era of PARPi, a breast cancer expert group meeting was convened.

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The synthesis of oxygenate products, including cyclic ketones and phenol, from carbon dioxide and water in the absence of gas-phase hydrogen has been demonstrated. The reaction takes place in subcritical conditions at 300 °C and pressure at room temperature of 25 barg. This is the first observation of the production of cyclic ketones by this route and represents a step towards the synthesis of valuable intermediates and products, including methanol, without relying on fossil sources or hydrogen, which carries a high carbon footprint in its production by conventional methods.

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Background: There is a need for a non-invasive, affordable, and reliable method for bone health screening in pediatric patients at risk.

Objective: To assess Bone Health Index (BHI) in pediatric patients with type 1 diabetes (T1D) and its relation to bone metabolism, age at onset, duration, control, and insulin dose.

Subjects And Methods: Left-hand radiographs were obtained from 65 patients with T1D, mean age 11.

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Objective: To assess the prevalence of underweight (UW), overweight (OW), and obesity in children and adolescents with type 1 diabetes (T1D).

Methods: An international cross-sectional study including 23 026 T1D children (2-18 years, duration of diabetes ≥1 year) participating in the SWEET prospective, multicenter diabetes registry. Body mass index SD score (BMI-SDS) was calculated using the World Health Organization BMI charts.

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For the first time, with the aid of differential scanning calorimetry, the thermal denaturation of fibrinogen under induced oxidation was studied. All fibrinogen structural elements detected by DSC (D region, αC-domain, and E region) are subjected to oxidation. Structural changes in fibrinogen molecule were characterized by the denaturation temperature, denaturation enthalpy, and van't Hoff enthalpy.

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Natural complex mixtures such as oil and dissolved organic matter play an important role in the economy and in the global carbon cycle. One of the most promising approaches for the investigation of the chemical structure of such substances is the combination of the high-resolution mass spectrometry and selective chemical reactions. Here, we report the investigation of the ozonation products of natural complex mixtures using Fourier transform ion cyclotron resonance mass spectrometry.

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For the first time, by using the complex of physicochemical methods (mass-spectrometry, differential scanning calorimetry, spectrofluorimetry, method of spectral and fluorescent probes, dynamic light scattering, and UV spectrophotometry), the oxidation-mediated modification of chemical and spatial structure of albumin has been studied. All albumin structural regions are subjected to oxidation, methionine and aromatic amino acids primarily involved in oxidation. The albumin melting shows a decrease in thermal stabilization of the structure and changing of aggregation upon oxidation.

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By using the mass-spectrometry method, the oxidative modifications of the fibrinogen Aα, Bβ, and γ polypeptide chains induced by its oxidation have been studied. The αC-region has been proven to be the most vulnerable target for the oxidizer (ozone) as compared with the other structural elements of the Aα chain. The Bβ chain mapping shows that the oxidative sites are localized within all the structural elements of the chain in which the β-nodule exhibits high susceptibility to oxidation.

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For the first time, by using mass-spectrometry method, the oxidation-mediated modification of the catalytic FXIII-A subunit of plasma fibrin-stabilizing factor, pFXIII, has been studied. The oxidative sites were identified to belong to all structural elements of the catalytic subunit: the β-sandwich (Tyr104, Tyr117, and Cys153), the catalytic core domain (Met160, Trp165, Met266, Cys328, Asp352, Pro387, Arg409, Cys410, Tyr442, Met475, Met476, Tyr482, and Met500), the β-barrel 1 (Met596), and the β-barrel 2 (Met647, Pro676, Trp692, Cys696, and Met710), which correspond to 3.9%, 1.

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Ten girls with sporadic central precocious puberty were screened for mutations in the maternally imprinted gene MKRN3. We detected 1 novel frameshift mutation (p.Arg351Serfs*44) and a previously described mutation (p.

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Topicality: The fast track technology means a complex of targeted measures involving rational preoperative preparation, minimally invasive surgery, regional anesthesia and short-acting anesthetics, and early postoperative rehabilitation. Elucidating the possibility of applying the fast track technology in neurosurgery, in particular in spinal surgery, is extremely topical. This is associated with the epidemiological data and the fact that minimally invasive techniques used in neurosurgery are highly expensive.

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LHX4 mutations are rare in combined pituitary hormone deficiency, and even rarer in isolated GHD. We describe a 14 years old boy who was referred for investigation of short stature. Convergent strabismus, nystagmus was present.

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Background: Intensified insulin delivery using multiple daily injections (MDI) or continuous subcutaneous insulin infusion (CSII) is recommended in children with type 1 diabetes (T1D) to achieve good metabolic control.

Objective: To examine the frequency of pump usage in T1D children treated in SWEET (Better control in Paediatric and Adolescent diabeteS: Working to crEate CEnTers of Reference) centers and to compare metabolic control between patients treated with CSII vs MDI.

Methods: This study included 16 570 T1D children participating in the SWEET prospective, multicenter, standardized diabetes patient registry.

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For the first time, the induced oxidative modification of cellular fibrin-stabilizing factor (cFXIII) has been studied. According to the electrophoresis analysis, the conversion of oxidized cFXIII into FXIIIa resulted in producing the enzyme that significantly lost the initial enzymatic activity. At the same time, FXIIIa subjected to induced oxidation was completely devoid of enzymatic activity.

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The effect on ozone-induced oxidation on the self-assembly of fibrin in the presence of fibrin-stabilizing factor FXIIIa of soluble cross-linked fibrin oligomers was studied in a medium containing moderate urea concentrations. It is established that fibrin oligomers were formed by the protofibrils cross-linked through γ-γ dimers and the fibrils additionally cross-linked by through α-polymers. The oxidation promoted both the accumulation of greater amounts of γ-γ dimers and the formation of protofibrils, fibrils, and their dissociation products emerging with increasing urea concentrations, which have a high molecular weight.

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Fibrinogen is extremely susceptible to attack by reactive oxygen species (ROS). Having been suffered an oxidative modification, the fibrinogen molecules, now with altered spatial structure and function of fibrin network, affect hemostasis differently. However, the potential effects of the oxidative stress on the early stages of the fibrin self-assembly process remain unexplored.

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Unlabelled: The use of computer information and Internet technologies to solve clinical problems becomes trivial but is still a topical and promising direction closely related to the «Healthcare 2.0» concept. The methodology for developing virtual patient consultation systems is associated with the capabilities to process obtained data and optimize the choice of optimal tactics for further treatment, taking opportunities of the Internet.

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