DNA Oxidation Photoinduced by Norharmane Rhenium(I) Polypyridyl Complexes: Effect of the Bidentate N,N′-Ligands on the Damage Profile

ReI-polypyridyl complexes have interesting and distinctive photochemical and photosensitizing properties. This work describes the capability to induce (or photoinduce) DNA damage of three ReI-complexes with a naturally occurring alkaloid called norharmane (nHo) as ligand: [Re(CO)3(nHo)(L)]CF3SO3 where L=2,2′-bipyridine (ReBpy), phenanthroline (RePhen) or dipyrido[3,2-a:2′,3′-c]phenazine (ReDppz). The interaction of the complexes with DNA was investigated by steady-state and time-resolved spectroscopy. Data show that the mode and strength of interaction depend on the chemical structure of the bidentate ligand. The complexes show a major static contribution to the overall interaction, giving rise to the formation of noncovalent adducts with DNA, and the particular trend observed was RePhen>ReDppz>ReBpy. Photo-oxidation at the purine bases represents the major DNA damaging mechanism. RePhen also induces single-strand breaks in a yield similar to that of base damage, suggesting an additional photosensitizing pathway. We also performed the Ames test to evaluate the cytotoxic and mutagenic properties of both non-irradiated and photoexcited complexes. RePhen, but not the other complexes, turned out to be both toxic and phototoxic for the bacteria.Fil: Maisuls, Iván. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); ArgentinaFil: Cabrerizo, Franco Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); ArgentinaFil: David Gara, Pedro Maximiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Ópticas. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones Ópticas. Universidad Nacional de La Plata. Centro de Investigaciones Ópticas; ArgentinaFil: Epe, Bernd. Johannes Gutenberg Universitat Mainz; AlemaniaFil: Ruiz, Gustavo Teodosio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentin

Cymantrene, Cyrhetrene and Ferrocene Nucleobase Conjugates: Synthesis, Structure, Computational Study, Electrochemistry and Antitrypanosomal Activity

A series of cymantrene- and cyrhetrene-nucleobase derivatives together with the ferrocene-adenine conjugates have been prepared and characterized. The key step in synthesis of all compounds involved an N1-regioselective Michael addition of the respective nucleobase nucleophile to an in situ generated organometallic acryloyl electrophile reagent. The mechanism of this reaction was examined by DFT calculations. A single crystal X-ray diffraction study of cymantrene-adenine (5) were carried out and revealed that the plane of the adenine and the cyclopentadienyl group are almost perpendicular to each other. The cyclic voltammetry measurements on the cymantrenyl-nucleobases showed irreversible behavior for all compounds which can be explain by a ligand exchange of carbonyls with the donor functionality of the nucleobases. Cymantrene and cyrhetrene ketone nucleobases displayed significant in vitro activity against Trypanosoma brucei a causative parasite of sleeping sickness. They showed no cytotoxicity against human HL-60 cancer cells

CT Assessment of Diagnostic Findings in Patients with Hepatocellular Carcinoma (HCC)

This article evaluates the role of radiofrequency ablation (RFA) in the management of hepatocellular carcinoma (HCC) in patients with hepatitis B-associated cirrhosis. RFA has emerged as a favored therapeutic approach due to its low recurrence rates and applicability in patients unfit for surgical resection. The case report details a patient with a 30 mm lesion, which was effectively treated with RFA under ultrasound guidance, resulting in a significant reduction in size and absence of complications at six-month follow-up. The findings highlight the importance of individualized treatment approaches, interdisciplinary collaboration, and the use of advanced imaging techniques in monitoring therapeutic outcomes

Evaluación del impacto de Covid-19 en el sector turístico ruso y sus escenarios de desarrollo en el contexto de la transformación de las cadenas de valor

This study is devoted to assessing the pandemic’s impact on the Russian tourism sector functioning. The authors determine that the spread of coronavirus in the world significantly affected the state of tourism in Russia, greatly reducing the volume of outbound and inbound tourism and depriving tourist companies of the source of income. All representatives of the tourism industry, such as travel agencies and operators, accommodation facilities, as well as transport companies specializing in tourist transportation, face negative effects of COVID-19. The article calculates the effects for the Russian economy caused by decreased tourist demand in 2020 in the context of indicators, such as gross output, employee number and wage fund for all types of economic activity. In conclusion, the work proposes scenarios for boosting the Russian tourism sector in the near future with regard to current conditions, and for each scenario identifies measures for their implementation.Este estudio está dedicado a evaluar el impacto de la pandemia en el funcionamiento del sector turístico ruso. Los autores determinan que la propagación del coronavirus en el mundo afectó significativamente el estado del turismo en Rusia, reduciendo en gran medida el volumen del turismo emisor y receptor y privando a las empresas turísticas de la fuente de ingresos. Todos los representantes de la industria turística, como agencias y operadores de viajes, facilidades de alojamiento, así como empresas de transporte especializadas en transporte turístico, enfrentan los efectos negativos del COVID-19. El artículo calcula los efectos para la economía rusa causados por la disminución de la demanda turística en 2020 en el contexto de indicadores, como la producción bruta, el número de empleados y el fondo de salarios para todo tipo de actividad económica. En conclusión, el trabajo propone escenarios para dinamizar el sector turístico ruso en un futuro próximo con respecto a las condiciones actuales, y para cada escenario se identifican medidas para su implementación. Palabras clave: COVID-19, Rusia, turismo interno, modelo Input-Output.  Key words: COVID-19, Russia, domestic tourism, Input-Output model

Nucleophilic additions to coordinated 1,10-phenanthroline: intramolecular, intermolecular, reversible, and irreversible

KN(SiMe3)2 reacts with [Re(CO)3(phen)(PMe3)]OTf via reversible addition to the phen ligand and irreversible deprotonation of the PMe3 ligand followed by intramolecular attack to phen by the deprotonated phosphane, whereas MeLi irreversibly adds to phen. The addition of MeLi has been shown to be intermolecular, unlike previously known nucleophilic additions to pyridines.The authors thank MINECO and FEDER (grant CTQ2015-70231-P) and Principado de Asturias (grantFC-15-GRUPIN14-103) forfunding, and Ministerio de Educación for an FPU predoctoral fellowship (to R.A.).Peer reviewe

Problems of tourism as a factor of regional development in the context of COVID-19 pandemic

Objective: to identify the problems of tourism functioning that limit its contribution to the socio-economic development of a region.Methods: the research uses a set of scientific methods: monographic (when studying tourism as a factor determining regional development); economic-statistical and comparative analysis (when studying the trends and patterns and determining the key limitations of the tourism industry development in the region), as well as the general scientific research methods such as synthesis, analysis, induction, deduction, etc.Results: tourism is one of the most important catalysts for the development of the Russian economy. This paper examines the development of tourism in the Russian Federation, and identifies the main factors and constraints for the internal tourism development, including the impact of the 2020 pandemic. Based on the analysis of tourism development in Vologda region, the main tendencies and problems of its functioning are defined. The conclusion is made about the insufficient development of transport infrastructure, a shortage of rooms for collective accommodation of high level, the reduction in the number of tour operators that hampers the industry’s contribution to the regional economy.Scientific novelty: it is found that the solution of infrastructure problems, as well as the diversification of the tourist supply, promoting the tourist demand, will help to increase the impact of tourism on the development of the region in the nearest future. Practical significance: the main provisions and conclusions of the article can be used for the study of regional tourism problems, as well as by the regional authorities when elaborating the programs for the domestic tourism development

Strategic-Based Approach in Developing of Tourism in the Context of Modeling Structural Changes in the Regional Economy

The goal of this study is a need for scientific substantiation of the use of a strategic approach to the development of the tourism sector in the region, considered as the direction of structural changes in the economy. For achieving this goal it is necessary to explore the existing approaches to strategizing, analyze the experience of strategic management of tourism in the regions, determine ways to developing this sphere. The novelty of this study consists in the formation of strategic areas of develo