Репозиторий Университета

© 2020 The Authors Purpose: To present the problems and possibilities of diagnostic and treatment in a patient with resistant exudative-constrictive pericarditis. Methods: The male patient 31 y. was admitted to the clinic due to exudative pericarditis and arthritis of the left knee joint. His medical history periodic febrile fever with a cough, episodes of syncope and atrial fibrillation, treatment with antibiotics and corticosteroids with a temporary effect. Results: No data were received for systemic disease, hypothyroidism, tumors. With CT in both lungs, small areas of fibrosis and lymphadenopathy were identified. Pericardial sheets diffusely thickened. EchoCG shows one liter of pericardial fluid with fibrin. All tests for viruses and tuberculosis are negative. Thoracoscopy was performed. Morphological examination showed tuberculosis granulomas with caseous necrosis. The growth of mycobacteria of tuberculosis from sputum was obtained. Therapy included pyrazinamide, ethambutol, levofloxacin, prednisolone 20 mg / day. Ponce's disease regressed. Due to the increase of constriction, subtotal pericardectomy was performed. Conclusion: Tuberculosis is one of the real causes of pericarditis with massive effusion and an outcome in constriction. The negative results of all laboratory tests for tuberculosis do not exclude the diagnosis. It is necessary to use invasive morphological diagnosis, including thoracoscopic biopsy.

© 2020 The Authors Purpose: To present the problems and possibilities of diagnostic and treatment in a patient with resistant exudative-constrictive pericarditis. Methods: The male patient 31 y. was admitted to the clinic due to exudative pericarditis and arthritis of the left knee joint. His medical history periodic febrile fever with a cough, episodes of syncope and atrial fibrillation, treatment with antibiotics and corticosteroids with a temporary effect. Results: No data were received for systemic disease, hypothyroidism, tumors. With CT in both lungs, small areas of fibrosis and lymphadenopathy were identified. Pericardial sheets diffusely thickened. EchoCG shows one liter of pericardial fluid with fibrin. All tests for viruses and tuberculosis are negative. Thoracoscopy was performed. Morphological examination showed tuberculosis granulomas with caseous necrosis. The growth of mycobacteria of tuberculosis from sputum was obtained. Therapy included pyrazinamide, ethambutol, levofloxacin, prednisolone 20 mg / day. Ponce's disease regressed. Due to the increase of constriction, subtotal pericardectomy was performed. Conclusion: Tuberculosis is one of the real causes of pericarditis with massive effusion and an outcome in constriction. The negative results of all laboratory tests for tuberculosis do not exclude the diagnosis. It is necessary to use invasive morphological diagnosis, including thoracoscopic biopsy.

© 2019 Recent observations of unusual ferroelectricity in thin films of HfO2 and related materials has attracted broad interest to the materials and led to the emergence of a number of competing models for observed behaviors. Here we develop the analytical description for a possible electrochemical mechanism of observed ferroelectric-like behaviors, namely the collective phenomena of elastic and electric dipoles originated from oxygen vacancies. The vacancies are formed initially in the vicinity of film surfaces, grain boundaries, and other types of inhomogeneities inside the film including those induced by the film treatment. Electric cycling makes the distribution of electric dipoles more homogeneous than it was initially, providing at the same time the significant decrease in depolarization field. The ferroelectric phase is induced by the “electrochemical” coupling, that is the joint action of the omnipresent electrostriction and “chemical” pressure, which lead to the sign change of the positive coefficient α at P2 in the order-disorder type thermodynamic functional. Negative coefficient α becomes the driving force of the transition to the long-range ordered ferroelectric phase with the spontaneous polarization P in the direction normal to the film surface. Using the above ideas, we estimated that the reversible ferroelectric polarization, as high as (5–20) μC/cm2, can be induced by oxygen vacancies in HfO2 films of thickness less than (20–30) nm. Semi-quantitative agreement with available experimental data is demonstrated.

© 2019 Recent observations of unusual ferroelectricity in thin films of HfO2 and related materials has attracted broad interest to the materials and led to the emergence of a number of competing models for observed behaviors. Here we develop the analytical description for a possible electrochemical mechanism of observed ferroelectric-like behaviors, namely the collective phenomena of elastic and electric dipoles originated from oxygen vacancies. The vacancies are formed initially in the vicinity of film surfaces, grain boundaries, and other types of inhomogeneities inside the film including those induced by the film treatment. Electric cycling makes the distribution of electric dipoles more homogeneous than it was initially, providing at the same time the significant decrease in depolarization field. The ferroelectric phase is induced by the “electrochemical” coupling, that is the joint action of the omnipresent electrostriction and “chemical” pressure, which lead to the sign change of the positive coefficient α at P2 in the order-disorder type thermodynamic functional. Negative coefficient α becomes the driving force of the transition to the long-range ordered ferroelectric phase with the spontaneous polarization P in the direction normal to the film surface. Using the above ideas, we estimated that the reversible ferroelectric polarization, as high as (5–20) μC/cm2, can be induced by oxygen vacancies in HfO2 films of thickness less than (20–30) nm. Semi-quantitative agreement with available experimental data is demonstrated.

© 2019 Recent observations of unusual ferroelectricity in thin films of HfO2 and related materials has attracted broad interest to the materials and led to the emergence of a number of competing models for observed behaviors. Here we develop the analytical description for a possible electrochemical mechanism of observed ferroelectric-like behaviors, namely the collective phenomena of elastic and electric dipoles originated from oxygen vacancies. The vacancies are formed initially in the vicinity of film surfaces, grain boundaries, and other types of inhomogeneities inside the film including those induced by the film treatment. Electric cycling makes the distribution of electric dipoles more homogeneous than it was initially, providing at the same time the significant decrease in depolarization field. The ferroelectric phase is induced by the “electrochemical” coupling, that is the joint action of the omnipresent electrostriction and “chemical” pressure, which lead to the sign change of the positive coefficient α at P2 in the order-disorder type thermodynamic functional. Negative coefficient α becomes the driving force of the transition to the long-range ordered ferroelectric phase with the spontaneous polarization P in the direction normal to the film surface. Using the above ideas, we estimated that the reversible ferroelectric polarization, as high as (5–20) μC/cm2, can be induced by oxygen vacancies in HfO2 films of thickness less than (20–30) nm. Semi-quantitative agreement with available experimental data is demonstrated.

© 2020 Elsevier B.V. Single phase barium titanate–bismuth ferrite ((1-x)BaTiO3-(x)BiFeO3, BTO-BFO) solid solutions were prepared using citric acid and ethylene glycol assisted sol-gel synthesis method. Depending on the dopant content the samples are characterized by tetragonal, tetragonal-pseudocubic, pseudocubic and rhombohedral structure as confirmed by Raman spectroscopy and XRD measurements. An increase of the BFO content leads to a reduction in the cell parameters accompanied by a decrease in polar distortion of the unit cell wherein an average particle size increases from 60 up to 350 nm. Non zero piezoresponse was observed in the compounds with pseudocubic structure while no polar distortion was detected in their crystal structure using X-ray diffraction method. The origin of the observed non-negligible piezoresponse was discussed assuming a coexistence of nanoscale polar and non-polar phases attributed to the solid solutions with high BFO content. A coexistence of the nanoscale regions having polar and non-polar character is considered as a key factor to increase macroscopic piezoresponse in the related compounds due to increased mobility of the domain walls and phase boundaries.

© 2020 Elsevier B.V. In this work, we study the effect of RF magnetron oblique angle deposition (OAD) on morphology, structure, and elemental composition of as-deposited and heat-treated Cu containing calcium phosphates. The control over the surface morphology and nano roughness provided by OAD is of great interest as both Mesenchymal Stem Cells and various types of bacteria respond strongly to nanoscale topography. A Cu substituted hydroxyapatite target was used to deposit coatings on the surface of titanium (Ti) and silicon (Si) substrates. The samples were placed at an oblique angle of 80° relative to the surface of the sample holder and in a normal configuration with respect to the flux direction and, therefore, parallel to the target. The dense homogeneous coatings with globular surface features deposited at normal flux incidence (NFI) configuration changed to elliptical, highly oriented structures with the direction dictated by the atomic shadowing effect when the substrate was deposited at an oblique angle. As-deposited thin films were subjected to post-deposition-heat-treatment at 700 °C in an Ar atmosphere. This led to a drastic change in the surface morphology and, namely, lost the directionality of the nanostructures. According to the X-ray diffraction data, the samples deposited obliquely showed preferential growth in the (002) plane and lower internal stress, than samples coated at NFI for both the Si and Ti substrates. The RMS roughness of the films deposited obliquely on Si was twice that of the films deposited at NFI (860 ± 80 pm and 408 ± 60 pm, respectively). However, it was not the case for the Ti substrate, the RMS roughness decreased from 42 ± 4 nm for coatings deposited at normal flux geometry to 33 ± 2 nm for coatings deposited obliquely. The heat-treatment of the samples deposited at 80° resulted in a significant increase in the surface roughness: 8 ± 0.7 nm for Si and 71 ± 4 nm for Ti substrates. The obtained results demonstrate that the oblique angle deposition can be used to fabricate nano-rough surface morphologies.

© 2020 Elsevier B.V. In this work, we study the effect of RF magnetron oblique angle deposition (OAD) on morphology, structure, and elemental composition of as-deposited and heat-treated Cu containing calcium phosphates. The control over the surface morphology and nano roughness provided by OAD is of great interest as both Mesenchymal Stem Cells and various types of bacteria respond strongly to nanoscale topography. A Cu substituted hydroxyapatite target was used to deposit coatings on the surface of titanium (Ti) and silicon (Si) substrates. The samples were placed at an oblique angle of 80° relative to the surface of the sample holder and in a normal configuration with respect to the flux direction and, therefore, parallel to the target. The dense homogeneous coatings with globular surface features deposited at normal flux incidence (NFI) configuration changed to elliptical, highly oriented structures with the direction dictated by the atomic shadowing effect when the substrate was deposited at an oblique angle. As-deposited thin films were subjected to post-deposition-heat-treatment at 700 °C in an Ar atmosphere. This led to a drastic change in the surface morphology and, namely, lost the directionality of the nanostructures. According to the X-ray diffraction data, the samples deposited obliquely showed preferential growth in the (002) plane and lower internal stress, than samples coated at NFI for both the Si and Ti substrates. The RMS roughness of the films deposited obliquely on Si was twice that of the films deposited at NFI (860 ± 80 pm and 408 ± 60 pm, respectively). However, it was not the case for the Ti substrate, the RMS roughness decreased from 42 ± 4 nm for coatings deposited at normal flux geometry to 33 ± 2 nm for coatings deposited obliquely. The heat-treatment of the samples deposited at 80° resulted in a significant increase in the surface roughness: 8 ± 0.7 nm for Si and 71 ± 4 nm for Ti substrates. The obtained results demonstrate that the oblique angle deposition can be used to fabricate nano-rough surface morphologies.

© 2020 Elsevier B.V. Pesticides can potentially contribute to the development of numerous neurodegenerative diseases. This study evaluates the effects of a six-pesticide mixture at doses around the no-observed-adverse-effectlevels (0 × NOAEL, control) and 0.25, 1 and 5 × NOAEL on behavior of Wistar rats. After 3, 6 and 12 months, rats were observed for neurobehavioral changes using the techniques of elevated plus maze and universal problemchamber, and the experiment was conducted thrice. The 3-month exposure revealed a decrease in the cognitive ability at the dose of 5 × NOAEL, and a dose-dependent research activity and anxiety. The 6-month exposurerevealed non-monotonic effects on the cognitive ability, with a decrease by 0.25 and 5 × NOAEL, as well as non-monotonic effects on anxiety, withan increase by 0.25 and 1 × NOAEL. A decrease was also observed in research activity at 5 × NOAEL. However, the 12-month exposure resulted to an increase in cognitive ability by 0.25 × NOAEL and in anxiety by 1 × NOAEL, as well as to a dose-dependent research activity. Repeating the trial showed that the cognitive ability increased from one trial to another, while the researching activity decreased and the anxiety increased by 0× NOAEL. In the groups exposed to pesticides mixture, the trends were different, showing that the exposure to pesticides combined with repeated trials, also influence the response of the animals. The resultsdemonstrate the occurrence of several dose-dependent behavioral responses, with negative effects occurring at doses that are considered safe. This study provides novel insights about time-dependent mixtures biology, and an important perspective to consider when conducting risk assessments.

© 2020 Cellulose nanocrystals (CNC), also known as nanowhiskers, have recently gained much attention due to their biodegradable nature, advantageous chemical and mechanical properties, economic value and renewability thus making them attractive for a wide range of applications. However, before these materials can be considered for potential uses, investigation of their toxicity is prudent. Although CNC exposures are associated with pulmonary inflammation and damage as well as oxidative stress responses and genotoxicity in vivo, studies evaluating cell transformation or tumorigenic potential of CNC's were not previously conducted. In this study, we aimed to assess the neoplastic-like transformation potential of two forms of CNC derived from wood (powder and gel) in human pulmonary epithelial cells (BEAS-2B) in comparison to fibrous tremolite (TF), known to induce lung cancer. Short-term exposure to CNC or TF induced intracellular ROS increase and DNA damage while long-term exposure resulted in neoplastic-like transformation demonstrated by increased cell proliferation, anchorage-independent growth, migration and invasion. The increased proliferative responses were also in-agreement with observed levels of pro-inflammatory cytokines. Based on the hierarchical clustering analysis (HCA) of the inflammatory cytokine responses, CNC powder was segregated from the control and CNC-gel samples. This suggests that CNC may have the ability to influence neoplastic-like transformation events in pulmonary epithelial cells and that such effects are dependent on the type/form of CNC. Further studies focusing on determining and understanding molecular mechanisms underlying potential CNC cell transformation events and their likelihood to induce tumorigenic effects in vivo are highly warranted.

© 2020 Cellulose nanocrystals (CNC), also known as nanowhiskers, have recently gained much attention due to their biodegradable nature, advantageous chemical and mechanical properties, economic value and renewability thus making them attractive for a wide range of applications. However, before these materials can be considered for potential uses, investigation of their toxicity is prudent. Although CNC exposures are associated with pulmonary inflammation and damage as well as oxidative stress responses and genotoxicity in vivo, studies evaluating cell transformation or tumorigenic potential of CNC's were not previously conducted. In this study, we aimed to assess the neoplastic-like transformation potential of two forms of CNC derived from wood (powder and gel) in human pulmonary epithelial cells (BEAS-2B) in comparison to fibrous tremolite (TF), known to induce lung cancer. Short-term exposure to CNC or TF induced intracellular ROS increase and DNA damage while long-term exposure resulted in neoplastic-like transformation demonstrated by increased cell proliferation, anchorage-independent growth, migration and invasion. The increased proliferative responses were also in-agreement with observed levels of pro-inflammatory cytokines. Based on the hierarchical clustering analysis (HCA) of the inflammatory cytokine responses, CNC powder was segregated from the control and CNC-gel samples. This suggests that CNC may have the ability to influence neoplastic-like transformation events in pulmonary epithelial cells and that such effects are dependent on the type/form of CNC. Further studies focusing on determining and understanding molecular mechanisms underlying potential CNC cell transformation events and their likelihood to induce tumorigenic effects in vivo are highly warranted.

© 2020 Elsevier Ltd A clear understanding of the normal anatomy of the glanular urethra is essential for anatomical reconstruction of the male urethra. In hypospadias surgery, tubularization of the neourethra over a catheter or stent has been the standard method for decades. However, the male urethra is not a tubular structure with uniform configuration and diameter by forming a fossa (navicularis) in the glans penis. We recently investigated the structural anatomy of the glanular urethra using magnetic resonance imaging (MRI). We have shown that the male urethra does not have a uniform tubular structure and not covered by the corpus spongiosum to the end. The glanular urethra that forms the “fossa navicularis” has a wider caliber than the proximal urethra. Its vertical elliptical shape resembles a laterally compressed slit-like passage. The fossa navicularis is covered by a thin layer of fibrous tissue (“septum glandis”) which is an extension of tunica albuginea of the corpus cavernosum and the corpus spongiosum. Our hypothesis is based on the results of MRI of the glanular urethra and the basic principles of fluid dynamics. We analyzed the flow dynamics of urine on this particular component of the urethra in terms of shape and structural properties. Because of its wider caliber than the proximal urethra, the glanular urethra (fossa navicularis) should cause an increase in pressure and a decrease in velocity of the urine flow. The navicular shape of the fossa and its elliptical external opening (the meatus) should allow urine to be expelled at higher flow rates and at opposite angles at the upper and lower corners which make the wave-like shape of the urine. It can be said that the changes in the volumetric form, pressure and velocity, as well as the wave-like shape of the urine flow are caused by the “fossa navicularis” covered by the “septum glandis”. We propose that the “fossa navicularis” and “septum glandis” play a role as ‘flow control chamber” in controlling the flow of the urine exiting the urethra, which must be taken into account for successful functional reconstruction of hypospadias.

© 2020 Elsevier GmbH Purpose: The plantaris muscle is a morphologically variable structure with regard to both its origin and insertion, and the course of the tendon. We here determined the pattern of branching and distribution of intramuscular nerves of the plantaris muscle to determine its usability for autologous transplantation. No information exists on the innervation of the plantaris muscle using Sihler's staining technique, and hence its intramuscular nerves. The main purpose of the work is to determine the pattern of branching and distribution of the intramuscular nerves of the plantaris muscle. Is the plantaris muscle a good transplant candidate? Materials and methods: Eighty lower limbs from cadavers (40 left, 40 right, 40 male, 40 female, age range 41–94 years) were fixed in 10% formalin solution and examined macroscopically as well as morphometrically with regard to the innervation pattern of the respective plantaris muscle. Afterwards Sihler's staining was used in all 80 plantaris muscles to identify the exact distribution of the muscular branch originating from the main nerve trunk in the muscle belly. Results: Two patterns of branching and nerve distribution could be intensified in the plantaris muscle: Type I, with a single pattern entire up to the muscle and then divided into superior and inferior intramuscular branches.; type II with a double innervation pattern (superior and inferior). The superior and inferior pattern were not connected to each other. Conclusion: The plantaris muscle reveals variability with two different innervation patterns. Type II is ideally suited for autologous transplantation. New classifications of innervation are desirable for individual muscles rather than a generalized approach.

© 2020 Elsevier B.V. Brain metastases manifest the advanced stage of breast cancer disease with poor prognosis for patient survival. Recent reports demonstrate that some therapeutic agents can activate the expression of several breast cancer-associated genes, whose products are involved in the onset and development of brain metastases. In this study, we discovered a functional link between KISS1 and E-cadherin that could be observed in both primary brain metastatic lesions and paired cell lines, such as parental CN34TGL and MDA-MB-231 and their respective brain metastatic subclones CN34Brm2Ctgl and MDA-MB-231Br. Remarkably, expression of KISS1 and E-cadherin genes consistently showed an inverse correlation in all of the above cell/tissue types. While E-cadherin expression was strongly upregulated in metastatic clones isolated from blood and brain, the levels of this protein in parental MDA-MB-231 cell line was low. Furthermore, E-cadherin upregulation can be artificially induced in MDA-MB-231Br and CN34Brm2Ctgl cell populations by knocking down KISS1 expression directly or through overexpressing the miR345 mimic. In the aggregate, our data suggest that the tumor microenvironment, which controls breast cancer spreading via miR345-regulated KISS1 expression, might modulate metastatic spreading by a mechanism(s) involving upregulation of E-cadherin production.

© 2020 Elsevier Inc. Mitochondria are essential for neuronal function because they serve not only to sustain energy and redox homeostasis but also are harbingers of death. A dysregulated mitochondrial network can cascade until function is irreparably lost, dooming cells. TBI is most prevalent in the young and comes at significant personal and societal costs. Traumatic brain injury (TBI) triggers a biphasic and mechanistically heterogenous response and this mechanistic heterogeneity has made the development of standardized treatments challenging. The secondary phase of TBI injury evolves over hours and days after the initial insult, providing a window of opportunity for intervention. However, no FDA approved treatment for neuroprotection after TBI currently exists. With recent advances in detection techniques, there has been increasing recognition of the significance and roles of mitochondrial redox lipid signaling in both acute and chronic central nervous system (CNS) pathologies. Oxidized lipids and their downstream products result from and contribute to TBI pathogenesis. Therapies targeting the mitochondrial lipid composition and redox state show promise in experimental TBI and warrant further exploration. In this review, we provide 1) an overview for mitochondrial redox homeostasis with emphasis on glutathione metabolism, 2) the key mechanisms of TBI mitochondrial injury, 3) the pathways of mitochondria specific phospholipid cardiolipin oxidation, and 4) review the mechanisms of mitochondria quality control in TBI with consideration of the roles lipids play in this process.

© 2020 A series of novel metal complexes of Cu(II), Ni(II), Zn(II), Cd(II), and Mg(II) with four N-heterocyclic derivatives of 2-arylhydrazono-1,3-dicarbonyl compounds were isolated and identified by FT IR, 1H NMR, EPR, and UV–Vis spectroscopy. The crystallographic data for two organic ligands as well as Mg(II) and Ni(II) complexes were obtained. It was indicated that the organic species exist in the form of hydrazo-tautomers. The Ni complex is monomeric and is characterized by the tridentate coordination of the ligand through a deprotonated N-atom of the hydrazo-fragment and two neighboring O-atoms of the carbonyl and deprotonated hydroxy-groups. In the case of the Mg complex the polymeric structure is observed with the additional coordination through the sulfamide group of the organic specie. Formation constants of the complexes in ethanol aqueous solutions were calculated and correlated with some physical characteristics of the metal cations. Structures of yet unstudied metal complexes were proposed based on quantum-chemical modeling at the DFT/B3LYP level.

© 2020 Elsevier Inc. This study reports the differences in toxic action between cadmium sulfide (CdS) and zinc sulfide (ZnS) nanoparticles (NPs) prepared by recently developed xanthate-mediated method. The aquatic toxicity of the synthesized NPs on four marine microalgae species was explored. Growth rate, esterase activity, membrane potential, and morphological changes of microalgae cells were evaluated using flow cytometry and optical microscopy. CdS and ZnS NPs demonstrated similar level of general toxicity and growth-rate inhibition to all used microalgae species, except the red algae P. purpureum. More specifically, CdS NPs caused higher inhibition of growth rate for C. muelleri and P. purpureum, while ZnS NPs were more toxic for A. ussuriensis and H. akashiwo species. Our findings suggest that the sensitivity of different microalgae species to CdS and ZnS NPs depends on the chemical composition of NPs and their ability to interact with the components of microalgal cell-wall. The red microalga was highly resistant to ZnS NPs most likely due to the presence of phycoerythrin proteins in the outer membrane bound Zn2+ cations defending their cells from further toxic influence. The treatment with CdS NPs caused morphological changes and biochemical disorder in all tested microalgae species. The toxicity of CdS NPs is based on their higher photoactivity under visible light irradiation and lower dissociation in water, which allows them to generate more reactive oxygen species and create a higher risk of oxidative stress to aquatic organisms. The results of this study contribute to our understanding of the parameters affecting the aquatic toxicity of semiconductor NPs and provide a basis for further investigations.

© 2020 Elsevier Inc. Mitochondria are essential for neuronal function because they serve not only to sustain energy and redox homeostasis but also are harbingers of death. A dysregulated mitochondrial network can cascade until function is irreparably lost, dooming cells. TBI is most prevalent in the young and comes at significant personal and societal costs. Traumatic brain injury (TBI) triggers a biphasic and mechanistically heterogenous response and this mechanistic heterogeneity has made the development of standardized treatments challenging. The secondary phase of TBI injury evolves over hours and days after the initial insult, providing a window of opportunity for intervention. However, no FDA approved treatment for neuroprotection after TBI currently exists. With recent advances in detection techniques, there has been increasing recognition of the significance and roles of mitochondrial redox lipid signaling in both acute and chronic central nervous system (CNS) pathologies. Oxidized lipids and their downstream products result from and contribute to TBI pathogenesis. Therapies targeting the mitochondrial lipid composition and redox state show promise in experimental TBI and warrant further exploration. In this review, we provide 1) an overview for mitochondrial redox homeostasis with emphasis on glutathione metabolism, 2) the key mechanisms of TBI mitochondrial injury, 3) the pathways of mitochondria specific phospholipid cardiolipin oxidation, and 4) review the mechanisms of mitochondria quality control in TBI with consideration of the roles lipids play in this process.

© 2020 A series of novel metal complexes of Cu(II), Ni(II), Zn(II), Cd(II), and Mg(II) with four N-heterocyclic derivatives of 2-arylhydrazono-1,3-dicarbonyl compounds were isolated and identified by FT IR, 1H NMR, EPR, and UV–Vis spectroscopy. The crystallographic data for two organic ligands as well as Mg(II) and Ni(II) complexes were obtained. It was indicated that the organic species exist in the form of hydrazo-tautomers. The Ni complex is monomeric and is characterized by the tridentate coordination of the ligand through a deprotonated N-atom of the hydrazo-fragment and two neighboring O-atoms of the carbonyl and deprotonated hydroxy-groups. In the case of the Mg complex the polymeric structure is observed with the additional coordination through the sulfamide group of the organic specie. Formation constants of the complexes in ethanol aqueous solutions were calculated and correlated with some physical characteristics of the metal cations. Structures of yet unstudied metal complexes were proposed based on quantum-chemical modeling at the DFT/B3LYP level.

© 2020 Elsevier Inc. This study reports the differences in toxic action between cadmium sulfide (CdS) and zinc sulfide (ZnS) nanoparticles (NPs) prepared by recently developed xanthate-mediated method. The aquatic toxicity of the synthesized NPs on four marine microalgae species was explored. Growth rate, esterase activity, membrane potential, and morphological changes of microalgae cells were evaluated using flow cytometry and optical microscopy. CdS and ZnS NPs demonstrated similar level of general toxicity and growth-rate inhibition to all used microalgae species, except the red algae P. purpureum. More specifically, CdS NPs caused higher inhibition of growth rate for C. muelleri and P. purpureum, while ZnS NPs were more toxic for A. ussuriensis and H. akashiwo species. Our findings suggest that the sensitivity of different microalgae species to CdS and ZnS NPs depends on the chemical composition of NPs and their ability to interact with the components of microalgal cell-wall. The red microalga was highly resistant to ZnS NPs most likely due to the presence of phycoerythrin proteins in the outer membrane bound Zn2+ cations defending their cells from further toxic influence. The treatment with CdS NPs caused morphological changes and biochemical disorder in all tested microalgae species. The toxicity of CdS NPs is based on their higher photoactivity under visible light irradiation and lower dissociation in water, which allows them to generate more reactive oxygen species and create a higher risk of oxidative stress to aquatic organisms. The results of this study contribute to our understanding of the parameters affecting the aquatic toxicity of semiconductor NPs and provide a basis for further investigations.