MORPHOFUNCTIONAL CHANGES IN RAT LUNGS UNDER THE INFLUENCE OF AFLATOXIN B1

Morphofunctional changes in the lungs of rats under the influence of aflatoxin B1 were studied. The data obtained indicate that aflatoxicosis causes marked regressive changes due to pulmonary insufficiency, which are accompanied by massive destruction of lung cells, the presence of altered fields of view of emphysema, diffuse inflammatory foci, as well as an increase in the number of mast cells.

Assessment of the Reproductive Health Status of Clarias Gariepinus (Burchell, 1822) in a River Impacted by Mercury from Clandestine Gold Mining: A Case Study of Bagoue River, Côte d’Ivoire

Pollution of aquatic ecosystems often results in adverse environmental disturbances, including individual and/or sub-individual changes in fish. The aim of the present study was to examine possible reproductive health effects in male and female, based on a histological assessment of Clarias gariepinus sampled in Bagoue River impacted by mercury from the artisanal gold mining. Fish were collected between August 2018 and April 2019 during two seasons from four stations differently impacted. A histological assessment was done on three target fish organs (liver, ovary and testis). Water and sediment samples were analysed for total mercury (T-Hg) concentration. Histological alterations were semi-quantitatively assessed, and the results were classified according to the severity of the histological response identified. Microscopic assessment revealed alterations of the gonads and liver tissues. A higher incidence of reaction pattern (Regressive changes, Inflammation and Circulatory disturbance) was found in liver tissues than in gonads tissues (Regressive changes). T-Hg levels were higher upstream than downstream in ovaries and testis tissues. Paradoxically, the lesions observed in these organs were more pronounced downstream than those found in fish from upstream during rainy season. According to total index, the organs examined downstream suffered severe damage unlike upstream sites. Also, comparison of degree of alteration between testes and ovaries indicates a greater impact of ovarian structures especially on downstream sites. The effect of anthropogenic impact appears to be visible downstream as the concentration of chemical pollutants and exposure time determine the severity of the damage. Alterations in ovarian follicles, spermatogenic cells and liver tissues may reflect damage to the process of gametogenesis, which may reduce the reproductive capacity of individuals over the long term.

Genesis and dynamics of the range of Daphne cneorum (Thymelaceae) within Ukraine

A detailed study of the geographical distribution and populations status in historical aspects of Daphne cneorum (Thymelaceae), a rare species in Europe, was conducted to establish the dynamics of its range in Ukraine. Analysis of phytogeographic and paleological data showed that this is a migratory relict species (sensu Szafer, 1975). As a tertiary relic, D. cneorum survived in the Volhynian-Podolian Upland. From this refugium, it migrated to the Polissya and Dnipro lowlands as well as the Dnipro and Lublin uplands in the interglacial and postglacial periods. The range of D. cneorum in Ukraine currently consists of two separate areas, Volhynian-Podolian and Dnipro fragments. The disjunction apparently arose as a result of inconsistency of the ecological conditions (acid soils on crystalline rocks) of the Ukrainian shield and physiological needs of the calcephilous species D. cneorum. In our opinion, the disjunctions between the Volhynian-Podolian, Belarus and Lublin parts of the range are of anthropogenic origin. Over the last century, an intensive degradation of populations and fragmentation of the range of D. cneorum took place in Ukraine. Anthropogenic pressure has led to regressive changes in the species range in the country. Due to low seed productivity, plant death is not compensated by replenishment and therefore in disturbed habitats populations of D. cneorum are completely eliminated. The species has apparently disappeared from the flora of Roztocze, Volhynian Upland and the Kremenets Mountains. Since the absolute protection regime is ineffective for D. cneorum populations, the need to develop conservation management for this species in natural habitats is emphasized.

What determines the number of auditory sensilla in the tympanal hearing organs of Tettigoniidae? Perspectives from comparative neuroanatomy and evolutionary forces

Insects have evolved complex receptor organs for the major sensory modalities. For the sense of hearing, the tympanal organ of Tettigoniidae (bush crickets or katydids) shows remarkable convergence to vertebrate hearing by impedance conversion and tonotopic frequency analysis. The main auditory receptors are scolopidial sensilla in the crista acustica. Morphological studies established that the numbers of auditory sensilla are species-specific. However, the factors determining the specific number of auditory sensilla are not well understood. This review provides an overview of the functional organization of the auditory organ in Tettigoniidae, including the diversification of the crista acustica sensilla, a list of species with the numbers of auditory sensilla, and a discussion of evolutionary forces affecting the number of sensilla in the crista acustica and their sensitivity. While all species of Tettigoniidae studied so far have a crista acustica, the number of sensilla varies on average from 15–116. While the relative differences or divergence in sensillum numbers may be explained by adaptive or regressive changes, it is more difficult to explain a specific number of sensilla in the crista acustica of a specific species (like for the model species Ancistrura nigrovittata, Copiphora gorgonensis, Gampsocleis gratiosa, Mecopoda elongata, Requena verticalis, or Tettigonia viridissima): sexual and natural selection as well as allometric relationships have been identified as key factors influencing the number of sensilla. Sexual selection affects the number of auditory sensilla in the crista acustica by the communication system and call patterns. Further, positive allometric relationships indicate positive selection for certain traits. Loss of selection leads to evolutionary regression of the auditory system and reduced number of auditory sensilla. This diversity in the auditory sensilla can be best addressed by comparative studies reconstructing adaptive or regressive changes in the crista acustica.

The impact of the economic crisis on labor rights in Brazil

This article carries out bibliographical research and analyzes the situation of the Brazilian workers in the context of the current national economic crisis, demonstrating an increase in unemployment rates after the approval of the 2017 labor reform by the National Congress. The economic analysis shows that the reform (considered here a counter-reform) was a measure of counter-trend planned by the capitalists to cope with the fall in profit rates. The trade unions’ struggle was not able to avoid the regressive changes in the Brazilian labor legislation, which deteriorate the labor contracts and the living conditions of the working class.

The methodology for endoluminal irreversible electroporation in porcine models

The aim of this study was to describe the methodology of the surgical technique for endoluminal irreversible electroporation in the biliary tract performed within the perihilar region in porcine models. Endoluminal irreversible electroporation of the common bile duct was performed on eight porcine models using an endoluminal device inserted during laparotomy. The endoluminal device consisted of three electrodes 1 cm in length, attached at 120 degrees around the balloon catheter. The procedure was conducted with the following parameters: number of pulses 90, voltage of 1500 V between each couple of electrodes. Cross sectional imaging and histopathological assessment were employed for evaluations of the ablation zone. Models were sacrificed 24 h and 96 h after ablation. The treatment was successful in all porcine models. All animals survived the defined study period. Peri-ablation oedema within the hepatoduodenal ligament and adjacent liver tissue could be measured on post-procedural MRI or CT. Perforation in the site of ablation developed in one model. Histopathological examination showed heavy regressive changes of the ablated tissue. The elastic membranes of the adjacent portal vein were preserved in all models. In our experience, this novel endoluminal modality used within the perihilar region in porcine models is a feasible and well predictable procedure. Further studies should explore the optimal protocol of catheter-based ablation to limit complications.