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A constituição das psicoses na teoria freudiana
(Universidade Federal de São Carlos, 2023-09-13) Souza, Josiane Rodrigues; Namba, Janaina; https://lattes.cnpq.br/5016873975206205; https://orcid.org/0000-0002-0878-5282; https://lattes.cnpq.br/0470839034527673; https://orcid.org/0000-0002-2221-7804
This study aims to investigate the formation of the theory of psychoses in Freud. Thus, in the first part of our research, we present aspects that demonstrate that the question of the genesis of psychoses is embedded in Freud's early investigations, starting from the phenomena of paranoia and hallucinatory confusion. Consequently, we highlight how the association between the origin of paranoia, the development of libido, and the concept of narcissism based on the Schreber Case assumes an important role within the theory of psychoses. Moving forward, our focus revolves around the analysis of the specificities that comprise the defense mechanism of psychoses and its conceptual reverberations concerning the rupture of the ego with objective reality, in light of the theorization of the second topic. Finally, we then propose a reflection on the relationship between psychoses and psychoanalytic treatment, drawing from certain concepts elements addressed throughout our research, which include the libidinal economy, the interplay between the death drive and psychoses, as well as the weakening of Ego (Ich) functions, with the aim of supporting the hypothesis that the economic expenditure of psychoses is an important key to understanding some of the impasses related to the psychoanalytic treatment of these cases.
Complexo de Ru(II)-perileno diimida para ativação do oxigênio singleto: agente teranóstico em melanoma
(Universidade Federal de São Carlos, 2023-09-13) Campos, Isabele Aparecida Soares de; Carlos, Rose Maria; https://lattes.cnpq.br/1589143355309943; https://orcid.org/0000-0002-0277-9789; https://lattes.cnpq.br/1562327061267725; https://orcid.org/0000-0003-1949-4445
In this study, a new perylene diimide ligand functionalized at the 1,7-bay positions with two pyrrolidine molecules and at the imide positions with 5,10-amino-phenanthroline (PDI-Py) and a new electron donor-acceptor dyad [Ru(phen)2(PDI-Py)]2+ (RuPDI-Py), where phen = 1,10-phenanthroline, was developed for potential applications in photomedicine by combining absorption and emission in the near-infrared region with the ability to generate singlet oxygen (1O2). The electrochemical, photophysical, and photochemical properties of the PDI-Py ligand and the RuPDI-Py dyad were investigated using steady-state and time-resolved spectroscopic techniques in organic solvents and water. The pyrrolidine substituent induced a shift in the absorption (720 nm) and fluorescence (767 nm, EM = 1.75 ns) to the near-infrared region of the PDI-Py ligand. In DMSO, the RuPDI-Py dyad preserved the absorption and fluorescence of the PDI-Py chromophore in the near-infrared region, whereas in the region between 350-550 nm there was an overlap of the absorption bands related to the 1*MLCT and S0→S2 electronic transitions of the chromophores [Ru(phen)3]2+ and PDI-Py, respectively, and the phosphorescence 3*MLCT was completely quenched. Transient absorption studies demonstrated that the excitation of the {Ru(phen)3} moiety in the dyad resulted in rapid photoinduced electron transfer (60 ps) between the constituent chromophores, generating the charge-separated intermediate {Ru3+-(PDI-Py●-) (4 μs) that decays to generate the long-lived triplet state 3*PDI-Py (36 μs), which can sensitize the formation of 1O2 (Δ = 0.40). In water, the RuPDI-Py dyad self-assembled into J-type molecular aggregates, which exhibited 1*PDI-Py fluorescence at 840 nm (τEM = 1.55 ns) and 3*MLCT phosphorescence at 620 nm (τEM = 1.3 μs). Furthermore, excitation of the {Ru(phen)3} moiety resulted in the formation of 3*PDI-Py (15 μs) and the generation of 1O2. The dependence of the photophysical properties of the RuPDI-Py dyad on the wavelength of the excitation light allowed modulation of its biological applications. Using 450 nm visible light, the dyad generated the cytotoxic species 1O2, which induced 100% inhibition of E. Coli colony growth at dyad concentrations above 2.5 μM after light treatment. In vitro studies with human melanoma cells of the MDA-MB-435 cell line demonstrated the photocytotoxicity of the dyad with an IC50 of 2.30 μM (PI > 108), indicating its potential application as a photosensitizer for antimicrobial and antitumor photodynamic therapy. In contrast, using light above 650 nm, only the fluorescence of the dyad in the near-infrared region was observed, which allowed monitoring of its cellular location preferentially in the cytoplasm of MDA-MB-435 cells, as well as monitoring the photoinduced damage by treatment with 450 nm light in cells and in mimetic models of phospholipid membranes, demonstrating the potential application of the dyad as a luminescent biomarker. Finally, polymeric polyacrylonitrile (PAN) nanofibers functionalized with the RuPDI-Py dyad were prepared using the electrospinning method and presented ideal characteristics to act as promising photoactive materials capable of generating 1O2 under irradiation with visible light for future applications in wound healing in the topical treatment of melanoma skin cancer.