Session THREE

Ismaray Govea, Florida International University.  Co-authors: Brandon Fernandez, Joseph Souchak, and Charles J. Dimitroff. Analysis of pro-melanoma metastasis factor, galectin-8, as a promoter of melanoma cell adhesion to vascular endothelium.  Melanoma is a deadly skin cancer responsible for most skin cancer-related deaths, with over 300,000 new cases diagnosed annually worldwide. The prognosis for advanced melanoma (Stage 4) remains poor, with a 5-year survival rate of about 30%, highlighting the need to better understand melanoma metastasis and find curative treatments. Our laboratory focuses on uncovering the molecular mechanisms of melanoma metastasis and has identified that metastatic melanoma cells lack pro-metastatic endothelial (E)-selectin-binding glycans, sialyl Lewis X and A (sLeX/A), commonly found on circulating tumor cells. Instead, melanoma cells exhibit elevated levels of linear poly-N-acetyllactosaminyl glycans that bind with galectin-8 (Gal-8), a glycan-binding protein elevated in metastatic melanoma patients. To explore Gal-8’s role in melanoma cell attachment, we performed parallel-plate flow chamber assays under physiologic shear stress conditions. Human A375 melanoma cells were exposed to recombinant Gal-8, control buffer, or Gal-8 inhibitor lactose, then tested for adhesion to vascular endothelial cells (ECs) under shear stress conditions simulating post-capillary venules. The results showed significantly increased melanoma cell adhesion in the presence of Gal-8 compared to controls or Gal-8 inhibition (p<0.001), indicating Gal-8 enhances adhesion and shear resistance of melanoma cells to ECs. Our findings suggest Gal-8 acts as an adhesion molecule promoting melanoma cell retention in blood vessels, identifying Gal-8 as a potential anti-metastatic therapeutic target. 

Nicole M. Mendoza Hung,  Florida International University.  Co-author: Katherine Kaiser. Quantifying Properties of Calcific Extracellular Vesicles from Osteoblasts and Vascular Smooth Muscle Cells.  Patients with osteoporosis frequently exhibit signs of vascular calcification, which is termed the “calcification paradox.” These conditions traditionally have been considered independent processes related to aging, although recent studies revealed a close relationship between the loss of bone mass and vascular calcification. Despite widespread acceptance of the calcification paradox, the specific mechanisms underlying the divergence in vascular smooth muscle cell (VSMC) and osteoblast (HOB) calcification remain unknown.

This project addresses this gap by analyzing calcifying extracellular vesicles (EVs) isolated from cultured HOBs and VSMCs using Tunable Resistive Pulse Sensing (TRPS) to accurately measure EV size, concentration, and charge. TRPS uses the Coulter Principle, where disruption of electric current due to EV movement across a nanopore provides physicochemical information.

Osteoblast-derived EVs that mediate bone mineralization, have previously been reported to be within the ectosome size range (10-400 nm). We hypothesize that VSMCs produce smaller, exosome-like EVs (40-160 nm) as a result of their unique mechanism of formation. We expect to observe increased calcifying EVs in cultures exposed to osteogenic stimuli. Analyses of EV duration within the TRPS pore provides insight on EV charge, a critical property associated with mineral formation. Negatively charged phospholipids help immobilize calcium ions to begin the mineral nucleation process.

This research aims to further clarify the mechanisms behind the calcification paradox and contribute to the broader understanding of the similarities and differences in the mineralization processes of bone and vascular cells. The findings could have significant implications for developing therapeutic strategies against vascular calcification and bone-related diseases.

Amanda Adams, University of Arizona.  Effects of Wood Fire Smoke on Ovarian Reserve.  According to the US EPA, chemicals released during wildfires are hazardous to those who are exposed. This includes millions of people across the US, but especially firefighters. This high exposure is proven to take a toll on their health, specifically their reproductive health. To study these effects more closely, mice were exposed to wood fire smoke for varying durations. After exposure, their ovaries were histologically processed. Then follicle enumeration techniques were used to determine these effects of the exposure on ovarian reserve. 

Taylor Brown, The University of Arizona. Spectral Analysis of Personal Care Products. My research utilized Infrared (IR) and Nuclear Magnetic Resonance (NMR) spectroscopy to analyze a range of personal care products, including shampoo, body wash, perfume, and cosmetics. The resulting spectral data were compared against reference spectra associated with known toxic chemicals. Upon analysis of the comparative spectra, we identified which products contained harsh or potentially toxic chemicals. 

Gabriel Agustín Rodríguez Carrillo, Universidad Nacional de Córdoba (UNC). El concepto de Democracia en la Jurisprudencia de la Corte  Interamericana de Derechos Humanos.  El objetivo de este trabajo es indagar en la concepción de democracia subyacente en los fallos de la Corte Interamericana de Derechos Humanos, buscando comprender su significado y alcance. Para lograr este propósito, se examina primero el estado actual de la Teoría de la Democracia y luego se analizan los pronunciamientos de la Corte durante las dos últimas décadas (2001-2022). Esta segunda parte también aborda la cuestión del derecho a la democracia y sus implicaciones.

Las conclusiones revelan que la Corte adopta un concepto de democracia representativa, constitucional y pluralista, destacando la protección de la libertad de expresión y las opiniones disidentes. Respecto al derecho a la democracia, se establece que existe en el sistema interamericano, aunque su desarrollo completo en términos técnicos y jurídicos, como su titularidad y exigibilidad, aún no ha sido abordado por la Corte.

Emilia Josela Romero, Universidad Nacional de Córdoba (UNC). Paradigma Etiologico y sus manifestaciones a lo largo de la historia Argentina: vinculación con practicas policiales abusivas.  El trabajo tiene por finalidad demostrar la influencia de las ideas fundantes del

paradigma etiológico en la historia argentina y como se refleja, tanto en la represión policial como en el creciente y constante estigma que impregna a toda la sociedad, y que actualmente tiene como blanco a la denominada “identidad villera''. A fines de poder desarrollar tales ideas, elegí tres hitos históricos argentinos: La esclavitud, la "Conquista del Desierto" y la última dictadura militar. Y vinculé tales momentos con el paradigma etiológico y la consecuente persecución focalizada en determinados grupos sociales vulnerables. Finalmente, concluí el trabajo explicando la situación actual, y la denominada ''criminalización de la pobreza".

Valentina Guzmán Arce, Universidad Nacional de Cuyo (UNCuyo). Co-autores: María Victoria Berberián, Nora Claudia Tomes. Morphological analysis of post-fusion events during the acrosomal reaction of human sperm: Protein machinery involved. The acrosomal reaction (AR) or acrosomal exocytosis is a membrane fusion process where the release of the spermatozoon's acrosomal contents occurs, and it is an essential requirement for fertilization to take place. We are interested in characterizing the morphological changes that occur during AR in human sperm and identifying the proteins involved in this process.

Although the structural rearrangements that occur in the sperm head during acrosomal exocytosis have been investigated, they remain a subject of debate. For instance, the details of the opening and expansion of the fusion pores, and the mechanism by which acrosomal expansion leads to the formation of hybrid vesicles, are still unknown. Therefore, the general aim of this project is to detect the morphological changes that occur post-fusion during AR and to determine the proteins involved in this process in human sperm. To achieve this, we will use a combination of cell and molecular biology techniques, biochemical approaches, and fluorescence and electron microscopy.

Maia Balod, Universidad Nacional de Cuyo (UNCuyo). Co-autores: Irina Ortiz, María Belén Hapon. Determination of Iodide in Urine Samples Using Silver Nanoparticles.  Iodine is an essential nutrient to ensure a healthy endocrine system and normal cognitive development. Some geographical regions present a natural deficiency of iodine, and their populations must be assessed to ensure that healthy levels of this element are being consumed. However, the traditional methods nowadays make iodine determination damaging for the environment or prohibitively expensive.

An attractive alternative is a simple colorimetric technique that exploits how iodide can change the morphology of silver nanoparticles, which in turn affects how light interacts with them. In addition to this, the stable complex formed between iodide and cyclodextrin is another useful interaction. The goal of this research work is to synthesize silver nanoparticles modified with cyclodextrin to determine the concentration of iodide in urine.

Silver nanoparticles were synthesized by reducing silver nitrate with sodium borohydride as a strong reducing agent, using sodium citrate, hydrogen peroxide and α-cyclodextrin as stabilizers and shaping regents. When potassium iodide solution was added, the change in color of the dispersion could be observed with the naked eye and using UV-Vis spectrometry. To determine iodide in urine samples, a pretreatment protocol to eliminate the interference of chloride was developed.

The use of the synthesized silver nanoparticles allowed to determine successfully whether the pre-treated urines were below or above the minimum iodide concentration recommended by the World Health Organization. This development could be utilized to easily carry out demographic studies on iodide intake.

Rodrigo Bautista, Universidad Nacional de Cuyo (UNCuyo). Optimization of 3D Printing Materials: Voronoi vs. Delaunay / Optimización de Material en Impresión 3D: Voronoi vs. Delaunay. Additive manufacturing is an essential production process in the Fourth Industrial Revolution. This process uses digital data to create three-dimensional objects by successively depositing layers of material. This technology allows for the creation of complex geometries that are unfeasible with traditional methods, and promotes more sustainable production by using reusable materials.

The objective is to analyze the efficiency of material usage in the manufacturing of parts, considering mechanical load demands and structural responses. In this research, two common tessellations are modeled: Delaunay triangulation and its dual, the Voronoi diagram. Mathematical duality relations are maintained to create two 3D models with the same volume and dimensions. Starting from a geometry obtained with CAD, a mesh of irregular triangles is generated using mesh manipulation software, and tessellation patterns are applied to generate the final models. These models are tested and compared with each other in order to achieve the proposed objective.

/

La manufactura aditiva es un proceso de fabricación esencial en la cuarta revolución industrial. Este proceso emplea datos digitales para crear objetos tridimensionales mediante la deposición sucesiva de capas de material. Esta tecnología permite la creación de geometrías complejas, inviables con métodos tradicionales, y favorece una producción más sostenible utilizando materiales reutilizables.

El objetivo es analizar la eficiencia del uso de materiales en la fabricación de piezas, considerando las solicitaciones de cargas mecánicas y las respuestas estructurales. En esta investigación, se modelan dos teselaciones comunes: la triangulación de Delaunay y su dual, el diagrama de Voronoi. Se mantienen relaciones matemáticas de dualidad para crear dos modelos 3D con el mismo volumen y dimensiones. Partiendo de una geometría obtenida con CAD, se obtiene una malla de triángulos irregulares, mediante software de manipulación de mallas, y se aplican patrones de teselación para generar los modelos finales. Estos modelos se ensayan y se comparan entre sí, a fin de alcanzar el objetivo propuesto.

Luciano Gomez Gomez, Universidad Nacional de Cuyo (UNCuyo). Co-Autores: Maia Balod, Gisel Ortiz, Irina Ortiz, María Belén Hapon. Quantification of Iodine in Salt and Historical Analysis of Goitre in Mendoza, Argentina. This research project focused on the quantification of iodine (I₂) concentration in table salt samples, as well as the historical analysis of goitre prevalence in the province of Mendoza, Argentina. Iodine deficiency has long been recognized as a major cause of thyroid disorders, particularly goitre, which has affected numerous regions in Argentina. By analysing different salt samples consumed in Mendoza, we aimed to evaluate iodine levels and their compliance with national public health regulations designed to prevent iodine deficiency disorders. The quantification of iodine was conducted using a redox titration method, which allowed for precise measurement of iodine content in the samples.

In addition to the chemical analysis, this study also explored the biogeochemical cycle of iodine, emphasizing the critical role microorganisms play in the mobilization and transformation of this element within various ecosystems. Microbial activity is a key factor in the release of iodine from both marine and terrestrial environments, influencing its availability in the food chain.

The historical prevalence of goitre in Mendoza was examined in conjunction with an analysis of public health interventions aimed at reducing iodine deficiency in the population. Through a review of policy measures implemented over the decades, we identified both successes and areas for improvement in iodine supplementation programs.

The results of this study offer a comprehensive assessment of the current availability of iodine in table salt in the region and its impact on public health, providing valuable insights for future iodine fortification policies in Mendoza.