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Photodynamic action of Pd(II)/porphyrin complexes against melanoma cells
(Universidade Federal de São Carlos, 2026-05-05) Moraes, Edynara Cruz de; Mello, Marcos Vinícius Palmeira de; Silva, Lívia do Carmo; Curcio, Juliana Santana De; Graça, Alex Marchezini; Dutra, Jocely de Lucena; Alonso, Antonio; Souza, Guilherme Rocha Lino de; Batista, Alzir Azevedo; Silveira-Lacerda, Elisângela de Paula; Gonçalves, Pablo José; https://lattes.cnpq.br/6784675018819363; https://lattes.cnpq.br/8894654634441028; https://lattes.cnpq.br/7092484043564604; https://lattes.cnpq.br/9577753232871923; https://lattes.cnpq.br/1230958955676787; https://lattes.cnpq.br/7966283355473231; https://lattes.cnpq.br/5013069863616789; https://lattes.cnpq.br/1127532567066692; https://lattes.cnpq.br/6469642481998660; https://lattes.cnpq.br/9390789693192751; https://lattes.cnpq.br/0515343409614452; https://orcid.org/0000-0003-2550-5315
Photodynamic therapy (PDT) is an emerging strategy for cancer treatment and represents a promising approach for melanoma, one of the most aggressive and therapy-resistant forms of skin cancer. In this study, meso-tetra(4-pyridyl)porphyrin complexes coordinated with palladium(II)/diphosphine ligands (Porf@dppe, Porf@dppp, Porf@dppb, and Porf@dppf; dppe = 1,2-bis(diphenylphosphino)ethane, dppp = 1,3-bis(diphenylphosphino) propane, dppb = 1,4-bis(diphenylphosphino)butane, and dppf = 1,1′-bis(diphenylphosphino)ferrocene), previously shown to display favorable lipophilicity and efficient singlet oxygen production, were evaluated againsthuman (A375) and murine (B16–F10) melanoma cells, as well as non-cancerous keratinocytes (HaCaT). Cytotoxicity measured after a 90 min incubation period yielded dark IC50 values between 0.6 and 8.6 μM, whereas light irradiation (λ = 415 nm, 1.8 J cm􀀀 2, 36 mW cm􀀀 2) resulted in markedly lower IC50 values in the nanomolar range (2–27 nM). Irradiation increased intracellular ROS levels, induced morphological alterations in A375 cells, inhibited long-term proliferation, and reduced cell migration, particularly for Porf@dppb and Porf@dppf. The highest cytotoxicity was observed for Porf@dppf, likely due to the redox-active ferrocene unit promoting Fentontype reactions and enhanced hydroxyl radical formation. Electron paramagnetic resonance (EPR) spin-trapping experiments confirmed light-induced generation of hydroxyl radicals and superoxide anion, with significantly higher hydroxyl radical production observed for Porf@dppf. The photodynamic activity of these complexes is attributed to efficient ROS production involving simultaneous contributions from both Type I and Type II mechanisms. Moderate binding to bovine serum albumin suggests possible albumin-mediated plasma transport. Overall, palladium(II)/diphosphine porphyrin complexes emerge as promising photosensitizers for melanoma photodynamic therapy.
Estrutura da metacomunidade de peixes em riachos urbanizados na Bacia do Rio Sorocaba
(Universidade Federal de São Carlos, 2026-05-05) Silva, Guilherme Raphael Camargo Arcanjo; Cetra, Maurício; https://lattes.cnpq.br/6775493342513120; https://lattes.cnpq.br/5205087039793385; https://orcid.org/0000-0003-0540-1228; Piratelli, Augusto João; Peressin, Alexandre; Smith, Werlber Senteio; Almeida, Rodrigo da Silva; https://lattes.cnpq.br/4747322084219058; https://lattes.cnpq.br/8678022880791435; https://lattes.cnpq.br/9695011413985414; https://lattes.cnpq.br/4423449163037358
Urbanization acts as a restrictive environmental filter that disrupts aquatic biodiversity through the "Urban Stream Syndrome." This study investigated the fish metacommunity structure in 18 urban streams in Sorocaba, SE Brazil, to determine whether community assembly is driven by environmental selection (species sorting) or spatial processes. We applied the Elements of Metacommunity Structure (EEM) framework, beta diversity decomposition (Baselga and Podani methods), and Asymmetric Eigenvector Maps (AEM) to model directional dispersal. A total of 2,246 individuals from 18 species were collected. EEM analysis revealed a Quasi-Clementsian pattern, characterized by significant positive coherence and high boundary clumping, indicating that species groups replace one another along a latent gradient of Physical Habitat Index (PHI). Beta diversity decomposition via the Podani method showed that richness difference (59.2%) outweighed replacement (40.7%), signaling a severe nestedness-like faunal impoverishment. Partial Redundancy Analysis (pRDA) confirmed that the environmental fraction (PHI) significantly explained community variation, while the pure spatial component (AEM) was non-significant. These results demonstrate that local habitat degradation specifically loss of canopy cover and substrate homogenization overrides regional dispersal in shaping urban fish assemblages. Sensitive species are eliminated without replacement by specialists, leaving "niche vacancies" occupied by tolerant generalists like Phalloceros harpagos. Conservation efforts must prioritize the restoration of riparian zones and instream morphological complexity over simple hydrological connectivity to mitigate biotic homogenization in tropical urban landscapes.
Avaliação Node-Place do sistema de transporte público metroviário da cidade de São Paulo
(Universidade Federal de São Carlos, 2026-05-05) Rodrigues, Thiago Teiji Sato Velasco; Guerreiro, Thais de Cassia Martinelli; http://lattes.cnpq.br/2650555786682535; https://orcid.org/0000-0001-5795-8875; http://lattes.cnpq.br/2984130547680148; https://orcid.org/0009-0007-2973-7910; Monari, Marcelo; Fonseca, Flávia; http://lattes.cnpq.br/5944412594047895; http://lattes.cnpq.br/5350911984549256; https://orcid.org/0000-0002-5562-3235; https://orcid.org/0000-0001-7744-5225
The metro system of São Paulo city is considered essential for urban mobility in the São Paulo metropolitan area and, given the daily volume of riders, the relationship between the system's access points and the urban space where it is inserted becomes an important element for urban planning and a driver of public policies. This study applies the Node-Place methodology, with adaptations, to evaluate the metro stations of São Paulo's urban rail system according to their connectivity with the public transport network, their functionality within the urban space, and their accessibility via different active transport modes. The results were also analyzed in relation to the sociodemographic profile of the population surrounding the areas of each station. The research is structured based on a bibliographic and bibliometric review that identifies the main indicators used in similar studies, which are organized into three categories: Node (connectivity), Place (land use), and Active Mobility (accessibility via active modes). An adaptation of the Analytic Hierarchy Process (AHP) was applied to weight the indicators based on their frequency in the literature and to calculate final scores for each category. Data were collected from official sources and analyzed using geoprocessing techniques, allowing for the analysis of all stations in the city’s metro network. Preliminary results reveal spatial inequalities among the stations, with higher performance in those located in central areas of the city, such as Sé, República, and Anhangabaú stations, which showed a high level of connectivity, diverse land use, and favorable conditions for active mobility, alongside a concentration of high-income and working age population. On the other hand, stations located at the edges of the network, such as Capão Redondo, Vila Sônia, and Campo Limpo, performed lower and presented a surrounding population more dependent on the quality of public transport infrastructure, including children, elderly and women, highlighting challenges in urban integration and the redevelopment potential of these areas. The methodology applied to the São Paulo context enables the identification of opportunities for intervention and territorial improvement, contributing to the strengthening of the public transport system and to more equitable, efficient urban planning aligned with the principles of Transit-Oriented Development (TOD).