Thermodynamic modelling as applied to the development of TRIP-Matrix-Composite materials: The Fe–Mg–Mn–Ti–Zr–O system

This thesis performed within the Collaborative Research Center 799 describes a development of the metal-ceramic thermodynamic databases as applied to the design of the TRIP-Matrix-Composite materials. A wide range of theoretical and experimental investigations have been carried out in the relevant systems of Fe–Mg–Zr–O, Mg–Ti–Zr–O and Mg–Mn–Zr–O. Thermodynamic data were obtained using experimental methods of calorimetry and ab-initio calculations. Phase relations in the constituent binary and ternary systems have been studied using different types of static and dynamic methods. The obtained results allowed an assessment of thermodynamic parameters of the aforementioned systems using CALPHAD approach. The thermodynamic calculations have been performed to predict interfacial reactions within the composite material as well as to made recommendations for the design and further development of production processes for TRIP-Matrix-Composite materials

Mudanças nas tendências turísticas decorrentes das restrições causadas pela pandemia de COVID-19

As the novel coronavirus infection (COVID-19) continues to spread throughout the world, the tourism industry operates under numerous social distancing constraints, which has a negative impact on demand, the economic performance of tourism businesses, and also leads to staff layoffs and numerous bankruptcies in the industry. The purpose of the article is to investigate changes in the established global trends in tourism under the influence of restrictions caused by the COVID-19 pandemic. The study presents an analysis of the impact of the COVID-19 pandemic on the tourism industry. The macrotrends in tourism before the introduction of restrictions due to the COVID-19 pandemic and the trends that emerged in tourism in the course of the pandemic are identified. The study suggests that the trends that made their appearance in tourism during the pandemic can contribute to the industry’s recovery from the crisis in the post-pandemic period. At the same time, the prospects for the tourism sector remain extremely unclear. The changes brought about by the pandemic force the authorities of virtually all countries of the world, especially those in which tourism is quite a significant sphere of development, to take a different approach to the formation of strategies and programs for the development of the tourism industry.A medida que la nueva infección por coronavirus (COVID-19) continúa propagándose por todo el mundo, la industria del turismo opera bajo numerosas restricciones de distanciamiento social, lo que tiene un impacto negativo en la demanda, el desempeño económico de las empresas turísticas y también conduce a despidos de personal y numerosos quiebras en la industria. El propósito del artículo es investigar los cambios en las tendencias globales establecidas en el turismo bajo la influencia de las restricciones causadas por la pandemia de COVID-19. El estudio presenta un análisis del impacto de la pandemia de COVID-19 en la industria del turismo. Se identifican las macrotendencias en el turismo antes de la introducción de restricciones por la pandemia del COVID-19 y las tendencias que surgieron en el turismo en el transcurso de la pandemia. El estudio demuestra que las tendencias que hicieron su aparición en el turismo durante la pandemia pueden contribuir a la recuperación de la industria de la crisis en el período pospandemia. Al mismo tiempo, las perspectivas para el sector del turismo siguen siendo muy poco claras. Los cambios provocados por la pandemia obligan a las autoridades de prácticamente todos los países del mundo, especialmente aquellos en los que el turismo es una esfera de desarrollo bastante significativa, a adoptar un enfoque diferente para la formación de estrategias y programas para el desarrollo de la industria turística.À medida que a nova infecção por coronavírus (COVID-19) continua a se espalhar pelo mundo, a indústria do turismo opera sob inúmeras restrições de distanciamento social, o que tem um impacto negativo na demanda, no desempenho econômico das empresas de turismo e também leva a demissões de funcionários e inúmeras falências no setor. O objetivo do artigo é investigar as mudanças nas tendências globais estabelecidas no turismo sob a influência das restrições causadas pela pandemia do COVID-19. O estudo apresenta uma análise do impacto da pandemia de COVID-19 na indústria do turismo. São identificadas as macrotendências do turismo antes da introdução das restrições devido à pandemia de COVID-19 e as tendências que surgiram no turismo no decurso da pandemia. O estudo sugere que as tendências que surgiram no turismo durante a pandemia podem contribuir para a recuperação do setor da crise no pós-pandemia. Ao mesmo tempo, as perspectivas para o setor de turismo permanecem extremamente incertas. As mudanças provocadas pela pandemia forçam as autoridades de praticamente todos os países do mundo, especialmente aqueles em que o turismo é uma esfera de desenvolvimento bastante significativa, a adotar uma abordagem diferente para a formação de estratégias e programas para o desenvolvimento da indústria do turismo

Intraductal papilloma of ectopic breast tissue in axillary lymph node of a patient with a previous intraductal papilloma of ipsilateral breast: a case report and review of the literature

The presence of ectopic breast tissue in axillary lymph nodes (ALN) is a benign condition that must be differentiated from primary or metastatic carcinoma. Here we report a patient who underwent excision of enlarged ALN 10 years after she had received surgical treatment of ipsilateral breast for an intracystic intraductal papilloma (IDP). Histological examination of the removed ALN revealed that the proliferative lesion consisted of papillary and tubular structures lined by luminal cuboidal cells and a distinct outer layer of myoepithelial cells resembling IDP of the breast. Immunostaining with a set of immunohistochemical markers including AE/AE3, alpha-smooth muscle actin and p63 in combination with estrogen and progesterone receptors confirmed the diagnosis of ectopic IDP

Low VHL mRNA Expression is Associated with More Aggressive Tumor Features of Papillary Thyroid Carcinoma

Alterations of the von Hippel-Lindau (VHL) tumor suppressor gene can cause different hereditary tumors associated with VHL syndrome, but the potential role of the VHL gene in papillary thyroid carcinoma (PTC) has not been characterized. This study set out to investigate the relationship of VHL expression level with clinicopathological features of PTC in an ethnically and geographically homogenous group of 264 patients from Serbia, for the first time. Multivariate logistic regression analysis showed a strong correlation between low level of VHL expression and advanced clinical stage (OR55.78, 95% CI 3.17-10.53, P<0.0001), classical papillary morphology of the tumor (OR52.92, 95% CI 1.33-6.44, P=50.008) and multifocality (OR51.96, 95% CI 1.06-3.62, P=50.031). In disease-free survival analysis, low VHL expression had marginal significance (P=50.0502 by the log-rank test) but did not appear to be an independent predictor of the risk for chance of faster recurrence in a proportion hazards model. No somatic mutations or evidence of VHL downregulation via promoter hypermethylation in PTC were found. The results indicate that the decrease of VHL expression associates with tumor progression but the mechanism of downregulation remains to be elucidated

Thermodynamic modelling as applied to the development of TRIP-Matrix-Composite materials: The Fe–Mg–Mn–Ti–Zr–O system

This thesis performed within the Collaborative Research Center 799 describes a development of the metal-ceramic thermodynamic databases as applied to the design of the TRIP-Matrix-Composite materials. A wide range of theoretical and experimental investigations have been carried out in the relevant systems of Fe–Mg–Zr–O, Mg–Ti–Zr–O and Mg–Mn–Zr–O. Thermodynamic data were obtained using experimental methods of calorimetry and ab-initio calculations. Phase relations in the constituent binary and ternary systems have been studied using different types of static and dynamic methods. The obtained results allowed an assessment of thermodynamic parameters of the aforementioned systems using CALPHAD approach. The thermodynamic calculations have been performed to predict interfacial reactions within the composite material as well as to made recommendations for the design and further development of production processes for TRIP-Matrix-Composite materials

Effective Approaches to Study the Genetic Variability of SARS-CoV-2

Significant efforts are being made in many countries around the world to respond to the COVID-19 pandemic by developing diagnostic reagent kits, identifying infected people, determining treatment methods, and finally producing effective vaccines. However, novel coronavirus variants may potentially reduce the effectiveness of all these efforts, demonstrating increased transmissibility and abated response to therapy or vaccines, as well as the possibility of false negative results in diagnostic procedures based on nucleic acid amplification methods. Since the end of 2020, several variants of concern have been discovered around the world. When information about a new, potentially more dangerous strain of pathogen appears, it is crucial to determine the moment of its emergence in a region. Eventually, that permits taking timely measures and minimizing new risks associated with the spreading of the virus. Therefore, numerous nations have made tremendous efforts to identify and trace these virus variants, which necessitates serious technological processes to sequence a large number of viral genomes. Here, we report on our experience as one of the primary laboratories involved in monitoring SARS-CoV-2 variants in Russia. We discuss the various approaches used, describe effective protocols, and outline a potential technique combining several methods to increase the ability to trace genetic variants while minimizing financial and labor costs

Expression of VHL tumor suppressor mRNA and miR-92a in papillary thyroid carcinoma and their correlation with clinical and pathological parameters

A growing body of evidence suggests a role of the von Hippel-Lindau (VHL) tumor suppressor gene in the progression of papillary thyroid carcinoma (PTC). Our previous study of VHL in PTCs showed that lower VHL expression was associated with aggressive tumor features, but we found no evidence for VHL downregulation through common genetic or epigenetic modifications. Several studies pointed to a role of microRNA-92a (miR-92a) in the regulation of VHL expression in different cancers. In the present study, we examined the expression levels of VHL mRNA and miR-92a in 42 pairs of PTCs and matched non-tumor thyroid tissues by means of quantitative RT-PCR. We explored the correlation between them and their association with clinicopathological parameters. The results revealed that both VHL and miR-92a were either up-or downregulated in PTCs compared to corresponding non-tumor tissues. On univariate analysis, lower VHL levels were significantly associated with extrathyroid spread (P = 0.022) and capsular invasion (P = 0.032). Multivariate analysis confirmed the association of low VHL with extrathyroid spread (OR 0.246, 95% CI 0.069-0.872, P = 0.038). Higher miR-92a among PTC tissues associated with the presence of nodal metastases (univariate analysis: P = 0.012; multivariate: OR 4.703, 95% CI 1.109-19.938, P = 0.036). A negative correlation between VHL and miR-92a was observed in a subgroup of PTCs having vascular invasion (P = 0.033, r = -0.673). The data here reported demonstrate that the expression of both VHL and miR-92a is deregulated in PTC tissues and that in some PTCs they may have opposite roles. These roles, as well as their diagnostic and/or prognostic utility, remain to be clarified

Protective Effect of Peptide Calcium Channel Blocker Omega-Hexatoxin-Hv1a on Epithelial Cell during Ischemia–Reperfusion Injury

Ischemia–reperfusion injury (IRI) is a common phenomenon that develops both from natural causes and during major operations. Many intracellular processes mediated by calcium ions are involved in the development of IRI. Currently, chemical calcium channel blockers are used but they have a number of limitations. In this article, we study the effect of the omega-hexatoxin-Hv1a peptide toxin, an alternative to chemical calcium channel blockers, on the mechanisms of IRI development in epithelial cell culture. The toxin was produced using solid phase peptide synthesis. IRI was caused by deprivation of glucose, serum and oxygen. The data obtained demonstrate that the omega-hexatoxin-Hv1a toxin in nanomolar concentrations is able to prevent the development of apoptosis and necrosis in epithelial cells by reducing the concentration of calcium, sodium and potassium ions, as well as by delaying rapid normalization of the pH level, affecting the mitochondrial potential and oxidative stress. This toxin can be used as an alternative to chemical calcium channel blockers for preventing tissue and organ IRI due to its low-dose requirement and high bioavailability

Intraductal papilloma of ectopic breast tissue in axillary lymph node of a patient with a previous intraductal papilloma of ipsilateral breast: a case report and review of the literature

Abstract The presence of ectopic breast tissue in axillary lymph nodes (ALN) is a benign condition that must be differentiated from primary or metastatic carcinoma. Here we report a patient who underwent excision of enlarged ALN 10 years after she had received surgical treatment of ipsilateral breast for an intracystic intraductal papilloma (IDP). Histological examination of the removed ALN revealed that the proliferative lesion consisted of papillary and tubular structures lined by luminal cuboidal cells and a distinct outer layer of myoepithelial cells resembling IDP of the breast. Immunostaining with a set of immunohistochemical markers including AE/AE3, alpha-smooth muscle actin and p63 in combination with estrogen and progesterone receptors confirmed the diagnosis of ectopic IDP. This case shows that even though benign proliferative change in ectopic breast tissue is an extremely rare phenomenon, this possibility should be taken into account for correct diagnosis.</p

Surgical management of primary thyroid carcinoma arising in thyroglossal duct cyst: An experience of a single institution in Serbia

Thyroglossal duct cyst (TDC) carcinoma is a comparable rare entity and treatment strategies have not been standardized. Here, we report a favorable outcome of TDC carcinoma patients based on our therapeutic strategy. Twelve patients with TDC carcinoma treated in our department from 1986 to 2012 were enrolled. Ten patients underwent Sistrunks procedure in other institutions and referred to our institution for re-operation after the diagnosis of TDC carcinoma and the remaining two underwent initial surgery in our institution. Eleven patients were diagnosed as papillary and one as follicular carcinoma originating from TDC. We performed total thyroidectomy for 11, and limited thyroidectomy for one patient. Three patients (25%) had carcinoma lesions in the thyroid. We routinely dissected level I bilaterally and 6 of 11 patients (55%) with papillary carcinoma-type TDC carcinoma had metastasis. Level II/III nodes were biopsied and if positive, we performed level II-IV dissection. Of the 5 patients positive for level II/III, 2 were also positive for level IV. For the 3 patients with synchronous carcinoma in the thyroid, we performed level VI dissection and two had metastasis in this level. To date, 1 patient showed a recurrence to the lung, but none of the patients in our series died of carcinoma. For surgery of TDC carcinoma, Sistrunks procedure, total thyroidectomy with level I dissection is mandatory. Whether level II-IV dissection is performed depends on pathology of biopsied level II/III nodes. Level VI dissection is also recommended especially when carcinoma lesions are pre/intra operatively detected in the thyroid