Reactive oxygen species in male reproduction: A boon or a bane?

Reactive oxygen species (ROS) are free radicals derived from oxygen during normal cellular metabolism. ROS play a crucial role in the physiological processes and signalling pathways associated with male fertility. At physiological concentrations, ROS act as molecular mediators of signal transduction pathways involved in the regulation of the hypothalamic–pituitary–gonadal axis, spermatogenesis and steroidogenesis. They also trigger the morphological changes required for sperm maturation, such as DNA compaction and flagellar modification. Furthermore, ROS modulate crucial processes involved in the attainment of sperm fertilising ability such as capacitation, hyperactivation, acrosome reaction and sperm–oocyte fusion. Conversely, oxidative stress prevails when the concentration of ROS overwhelms the body's antioxidant defence. Various endogenous and exogenous factors enhance the synthesis of ROS resulting in the disruption of structural and functional integrity of spermatozoa through the induction of apoptotic pathway and oxidation of molecules, such as lipids, proteins and DNA. Therefore, maintenance of a balanced redox state is critical for normal male reproductive functions. This article discusses the dual role of ROS in male reproduction, highlighting the physiological role as well as their pathological implications on male fertility

Photographic Education. Analysis of a didactic sequence designed from the “workshop tools”

El objetivo del trabajo es reflexionar sobre la educación fotográfca, teniendo en cuenta el rol central que ocupa la fotografía en la cultura actual. El trabajo analiza la propuesta pedagógica de la Cátedra de Fotografía de la Universidad Nacional de Córdoba y examina la puesta en práctica de una secuencia didáctica diseñada a partir de las Herramientas de Taller de Bibi Anguio. Los resultados obtenidos muestran algunas ventajas de su aplicación y otras difcultades que no pudieron resolverse, concluyendo en la necesidad de una revisión de la propuesta pedagógica de la Cátedra. Finalmente, se propone la formulación de una estrategia educativa que fomente tanto la aprehensión de las herramientas técnicas fotográfcas como la alfabetización visual y a la utilización de sus recursos discursives.The objective of this work is to reflect about photographic education, considering the central role occupied by photography in today’s culture. The paper analyzes the pedagogical proposal of the Cathedra of Photography of the National University of Córdoba and examines the implementation of the didactic sequence designed in Bibi Anguio´s Workshop Tools. The results present some advantages of this application and some others difculties that could not be resolved, concluding in the need of a revision of the pedagogical proposal of the Cathedra. Finally, it is proposed the formulation of an educational strategy that promotes both the apprehension of photographic technical tools as visual literacy and the use of their discursive means

LA FOTOGRAFÍA COMO EL NUEVO LENGUAJE VISUAL DE LA RUSIA REVOLUCIONARIA. EL CASO DEL GRUPO LEF (1923-1928)

The article has as an object of study the conception of photography developed by the LEF Group. The study shows that its members, despite their theoretical differences, advocated for a notion of photographic image as visual text. They follow the theoretical guidelines of Constructivism not only as a formal artistic style but also as a constructor of the Russian Revolution. The first part of the text describes the conformation of the group and its principals theoretical foundations. The second part specifically recovers the notion of photography developed by the group and analyzes, through documents, the broad vision of the photography that the group created as a semiotic process. The purpose of this article is to promote a research field that has not yet been fully explored, the photographic aesthetics.Este artículo tiene como objeto de estudio la concepción sobre fotografía que desarrolló el grupo LEF. El estudio muestra que sus miembros, pese a sus diferencias teóricas, abogaron por una noción de la imagen fotográfica como texto visual siguiendo con los lineamientos teóricos del constructivismo como estilo artístico formal pero, también, formador de la Revolución Rusa. La primera parte desarrolla la conformación del grupo y sus principales fundamentos teóricos. La segunda parte recupera específicamente la noción de fotografía del grupo y analiza, a través de los documentos e imágenes fuentes, la visión amplia que de la fotografía tuvo el grupo como proceso semiótico. La tarea realizada tiene como fin impulsar un campo de investigación aún poco explorado, el de la estética fotográfica

Alexander Ródchenko in LEF (1923-1928). The use of the unconventional as a revolutionary language

El presente artículo rescata el estilo fotográfico de Alexander Ródchenko y sus seguidores en la revista rusa LEF (1923-1925) y Novyy LEF (1927-1928). Para estos artistas avanzados, la fotografía fue la herramienta artística por excelencia no sólo por sus cualidades técnicas de rapidez y facilidad de traslación en el espacio sino también, por su lenguaje artístico. La investigación muestra cómo estos fotógrafos dentro de un ambiente revolucionario incorporaron lo no convencional al lenguaje fotográfico ampliando significativamente las posibilidades discursivas de la fotografía.The present article rescues the photographic style of Alexander Ródchenko and his followers in the Russian magazine LEF (1923-1925) and Novyy LEF (1927-1928). For these advanced artists, the photography was the artistic tool by excellence not only for its technical qualities of speed and translation in the space but also, for the possibilities of its artistic language. The research shows how these photographers within a revolutionary environment incorporated the unconventional into the photographic language expanding significantly the discursive possibilities of photography

Photography in Russian symbolism and constructivism. Reflections on his ontology

El presente trabajo examina las imágenes fotográficas publicadas en la revista prerrevolucionaria Mir iskusstva, entendida como uno de los íconos del simbolismo ruso de fin de siglo, y las compara con las fotografías de las revistas constructivistas LEF y Novyy LEF, revistas emblemáticas de la vanguardia soviética de principios de siglo XX. La investigación sostiene como hipótesis principal que cada revista definió a la fotografía según las creencias y convicciones de cada contexto artístico. Como hipótesis secundaria, se afirma que la fotografía se encuentra íntimamente ligada a su tiempo y que fueron los discursos de cada contexto histórico los que determinaron su ontología.The present work examines the photographic images published in the pre-revolutionary magazine Mir iskusstva, understood as one of the Russian symbolism icons of the end of century, and compare them with the photos of the constructivist magazines LEF and Novyy LEF, flagship journals of the Soviet avant-garde of the beginning of the twentieth century. The main hypothesis argues that each magazine defined photography according to the beliefs and convictions of each artistic context. As a secondary hypothesis, affirm that photography is intimately linked to its time and that it was the discourses of each historical context that determined its ontology.Instituto de Investigaciones en Humanidades y Ciencias Sociale

The Mechanisms and Management of Age-Related Oxidative Stress in Male Hypogonadism Associated with Non-communicable Chronic Disease

Androgens have diverse functions in muscle physiology, lean body mass, the regulation of adipose tissue, bone density, neurocognitive regulation, and spermatogenesis, the male repro- ductive and sexual function. Male hypogonadism, characterized by reduced testosterone, is com- monly seen in ageing males, and has a complex relationship as a risk factor and a comorbidity in age-related noncommunicable chronic diseases (NCDs), such as obesity, metabolic syndrome, type 2 diabetes, and malignancy. Oxidative stress, as a significant contributor to the ageing process, is a common feature between ageing and NCDs, and the related comorbidities, including hypertension, dyslipidemia, hyperglycemia, hyperinsulinemia, and chronic inflammation. Oxidative stress may also be a mediator of hypogonadism in males. Consequently, the management of oxidative stress may represent a novel therapeutic approach in this context. Therefore, this narrative review aims to discuss the mechanisms of age-related oxidative stress in male hypogonadism associated with NCDs and discusses current and potential approaches for the clinical management of these patients, which may include conventional hormone replacement therapy, nutrition and lifestyle changes, ad-herence to the optimal body mass index, and dietary antioxidant supplementation and/or phyto-medicines.O

Hybrid α\alpha-attractors, primordial black holes and gravitational wave backgrounds

We investigate the two-stage inflation regime in the theory of hybrid cosmological $\alpha$-attractors. The spectrum of inflationary perturbations is compatible with the latest Planck/BICEP/Keck results, thanks to the attractor properties of the model. However, at smaller scales, it may have a very high peak of controllable width and position, leading to a copious production of primordial black holes (PBH) and generation of a stochastic background of gravitational waves (SGWB).Comment: 39 pages, 12 figure

Cytoprotective and Antigenotoxic Properties of Organic vs. Conventional Tomato Puree: Evidence in Zebrafish Model

In this in vivo study, we investigated cytoprotective and antigenotoxic effects of commercial tomato puree obtained from conventional vs. organic farming systems (pesticides vs. pesticide-free agriculture, respectively). This is relevant as pesticides are widely used in agriculture to prevent pests, weeds, and the spread of plant pathogens. By exposing zebrafish to tomato puree alone and in combination with H2O2 (a well-known genotoxic agent), we analyzed the percentage of fish survival, cell viability, intracellular concentration of reactive oxygen species (ROS), DNA fragmentation index (DFI%), and genomic template stability (GTS%). Fish exposed to organic puree showed higher fish survival and cellular viability, lower DFI% and ROS, and improved GTS%. Our results suggest a higher cytoprotective and antigenotoxic effect of organic pesticide-free tomatoes, probably because the activity of natural phytochemicals is not affected by the presence of toxic residues, which are otherwise produced by pesticides used in conventional farming systems. Our study points out the importance of considering alternative strategies in agriculture to minimize the genotoxic impact of chemical pesticides

The impact of Covid-19 vaccines on male semen parameters: A retrospective cohort study

The emergence of SARS-CoV-2 and the subsequent COVID-19 pandemic necessitated the development of adequate vaccines. Despite vaccines being demonstrated to be safe and effective for preventing severe disease and death, vaccine hesitancy remains. Reasons include concerns over adverse effects on male fertility, which have not been widely investigated. Therefore, this study is aimed at determining the impact of COVID-19 vaccination on semen parameters in a retrospective cohort study of South African males undergoing fertility assessment. The patients for this study were adult men who have previously undergone routine semen analysis for fertility assessment at Androcryos Andrology Laboratory (Johannesburg, South Africa) between March 2021 and March 2022. They also received vaccination within 3 months following a semen analysis and underwent a second semen analysis any time post-COVID-19 vaccination. From 277 records analysed, 46 patients met the inclusion criteria, receiving the Pfizer-BioNTech (BNT162b1) (63%), Johnson and Johnson (JNJ-78436735/Ad26.COV2S) (34.8%), and the AstraZeneca (AZD1222) (2.2%) vaccines. Sperm concentration significantly increased postvaccination (P = 0:0001), with no significant changes in semen pH, volume, total sperm count, progressive motility, normal sperm morphology, or chromatin condensation. Results were not influenced by age, type of vaccine received, and the number of days following vaccination, as depicted by multiple regression analysis. In conclusion, there is no evidence of a negative impact of COVID-19 vaccination on male semen parameters, which is consistent with the emerging literature on COVID-19 vaccination and male fertility. COVID-19 vaccinations should not be dismissed based on fear of adverse effects on male fertility parameters

Total antioxidant capacity—Relevance, methods and clinical implications

Oxidative stress is pre‐empted by an adequate level of antioxidants, which scavenge oxidants when they are produced in excess by different sources, including leukocytes and immature spermatozoa. Enzymatic antioxidants, such as superoxide dismutase, catalase and glutathione peroxidase, and several non‐enzymatic antioxidants (proteins, vitamins and minerals), working as oxidant scavengers and cofactors of enzymatic antioxidants have been identified in seminal plasma. The total antioxidant capacity (TAC) is a diagnostic test that can be utilised in the male infertility workup. TAC measures the amount of total antioxidants in seminal plasma. Therefore, it provides an assessment of the reductive potential in seminal plasma. Several studies have investigated the diagnostic application of TAC in various andrology conditions. There is substantial evidence in the literature to show that infertile patients have lower seminal TAC in comparison with fertile men. Moreover, there is a positive correlation between TAC and seminal parameters, such as sperm concentration, motility and morphology. Evaluation of TAC together with reactive oxygen species (ROS) and sperm DNA fragmentation index (DFI) may be beneficial in the diagnosis of male infertility.https://doi.org/10.1111/and.1374