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    Performance of Multiplex Detection Method of IgM Class Antibodies against Toxoplasma gondii, Rubella and Human Cytomegalovirus
    (JSciMed Central) Almeida, Rainara Moreno Sanches de; Ogawa, Guilherme Maerschner; Custódio, Paulo Rogério Siqueira; Sampaio, Maria Alcantara Socorro; Silva, Newton Soares da; Soares, Cristina Pacheco
    Serological diagnosis during neonatal screening is crucial in disease prevention. Among the infectious diseases, the most common are toxoplasmosis, rubella, and cytomegalovirus. Traditional diagnostic methods are used to detect a single infectious agent per test. The use of multiplex detection methods increases productivity and reduces the amount of material used, resulting in a more efficient test from a technical, environmental, and economic point of view. The study’s objective was to evaluate the performance of a new diagnostic method aimed at neonatal screening using the multiplex platform of magnetic microspheres from the company Luminex Corporation. For this, tests were carried out for analytical validation of the diagnostic product developed following the rules of the National Health Surveillance Agency (ANVISA) of Brazil. The parameters evaluated were repeatability, reproducibility, linearity, robustness, high dose, minimum detection limit, and analytical specificity. All data obtained met the acceptance criteria of RDC 166/17 of 2017 for the use of the diagnostic product in the national territory. Repeatability and reproducibility tests showed a CV of less than 15% between replicates of the same operator and different operators. The kit showed linearity throughout the operating range with R2 above 0.990, and no effect of high-efficiency dose was observed in the chosen working dilution. In addition, the kit did not show interference from the matrix with the results, and it was observed that small and deliberate changes in the incubation time of each reagent did not have a significant effect on the data obtained.
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    Influence of Hydrocortisone in Chemotherapy and Photodynamic Therapy in HEp-2 Cells
    (Clinics in Oncology) Moraes, Carlos Dailton Guedes de Oliveira; Godoi, Bruno Henrique; Silva, Newton Soares da; Soares, Cristina Pacheco
    Aim: Cancer cells exhibit resistance to the immune response by regulating and altering the expression of mediators responsible for immune cell recruitment and disease progression. Cortisol is a natural hormone that may be associated with diseases such as cancer by stimulating stress and altering the cellular environment, favoring uncontrolled division and contributing to the inhibition of the immune response. In contrast, current therapeutic strategies do not present significant concerns about stress as a variable in cancer diagnosis and prognosis. The response of HEp-2 cells to stress induced by hydrocortisone and to treatment with Cyclophosphamide (CP) and Photodynamic Therapy (PDT) was analyzed. Methods: One mM of hydrocortisone induced stress in the cells. Cells were treated with 200 μg/ mL of cyclophosphamide or Aluminum Phthalocyanine Tetrasulfonate (AlPcS4) photosensitizer, LED irradiation (660 nm wavelength), intensity of 25 mW/cm2, power of 70 mW, fluence of 5 J/ cm2, characterizing the PDT. All groups were evaluated after 24 h and 48 h. Results: Assessment of stress-inducing mitochondrial activity and cell viability were performed, and the results demonstrated that hydrocortisone significantly altered the rate of cell death, compromising the effects of CP. Conclusion: However, hydrocortisone did not change the cell death rates caused by PDT, indicating the possibility of this hormone as an alternative therapy.
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    Estimation of the DNA damage in Girardia tigrina (Girard, 1850) after exposure to radiation under extreme conditions
    (Brazilian Journals Publicações de Periódicos) Benitz, Tabatha; Oliveira, Matheus Salgado de; Lopes, Karla Andressa Ruiz; Soares, Cristina Pacheco; Morais, Flavia Villaça; Velho, Nádia Maria Rodrigues de Campos
    The use of planarians as experimental models has been increased worldwide especially due to their high capacity of tissue regeneration and ease of laboratory maintenance. The current study aims to assess the genetic damage of Girardia tigrina after exposure of stressors in conditions such as: critical temperature, critical pH, hypergravity (4.4G) and low power laser (685nm). 18 specimens of G. tigrina were used, the extreme conditions mentioned were experimental group with 3 specimens each, and 3 for the control group, all specimens were submitted to the Comet Assay after exposure of stressors, and control group with no extreme condition exposure. The extreme stimuli of critical temperature and pH, hypergravity and low power laser irradiation, caused genetic damages to the G. tigrina, for hypergravity and low-power laser stressors the damage was higher in the pharyngeal and post-pharyngeal regions of the animal with a greatest area of comet tail dragging for the post-pharyngeal region. The extreme stimuli of critical temperature and pH, hypergravity and low power laser irradiation caused genetic damages in planarians Brazilian Journal of Development ISSN: 2525-8761 12160 Brazilian Journal of Development, Curitiba, v.8, n.2, p.12159-12177 feb. 2022. G. tigrina, especially in samples from the pharyngeal and post-pharyngeal regions of the flatworms body assessed by the Comet Assay.
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    Biomodulatory effect of low intensity laser (830 nm.) in neural model 9L/lacZ
    (CDRR Editor) Zabeu, Antonieta Marques Caldeira; Carvalho, Isabel Chaves Silva; Soares, Cristina Pacheco; Silva, Newton Soares da
    Currently, research is advancing with low-intensity laser (LIL) in cells of the central nervous system, with the aim of evaluating the benefits of this therapy in neurological disorders such as Alzheimer's, stroke, ischemia, epilepsy, among others. The aim of this study was to verify the biomodulatory and biostimulatory effects of LIL in neural cell culture. Diode laser at wavelength λ = 830 nm, power 40 mW, in continuous mode, was applied on the 9L/lacZ cell line with energy densities of 0.5 to 3 J/cm . The analysis was performed 24 hours after irradiation, the results of cell viability showed a difference between the control and irradiated groups. As for the occurrence of apoptosis, no significant manifestation was observed between the control group compared to the irradiated group (P = 0.9956); there was a significant difference between apoptosis and death by necrosis between the control and treated groups (P<0.001). In the comet assay no statistically significant differences were observed. Regarding the objective of evaluating whether LIL promotes early activation of apoptosis or proliferation of 9L/lacZ cells at different energy densities of the infrared diode laser, we observed an increase in the number of neural cells, highlighting the action of biomodulation. Furthermore, LIL did not promote the activation of programmed cell death - apoptosis and did not show any indication of DNA damage by the comet assay. The results of this study are indicative that the laser in the near infrared has a positive interaction with neuronal cells.
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    Neuroprotective effects of taurine on SH-SY5Y cells under hydrocortisone induced stress
    (CDRR Editors) Rossato, Rafaella Carvalho; Granato, Alessandro Eustaquio Campos; Moraes, Carlos Dailton Guedes de Oliveira; Salles, Geisa Nogueira; Soares, Cristina Pacheco
    Alzheimer's disease (AD) is the most common, progressive and irreversible neurodegenerative disorder, characterized by memory loss, cognitive impairment and behavioral abnormalities. Although there is no cure, several study strategies seek to elucidate mechanisms of the disease. Recent studies address the benefits of taurine. Thus, the present study aims to analyze neuroprotective effects of taurine in human neuroblastoma (SH-SY5Y), using an in vitro experimental model of oxidative stress induced by hydrocortisone. This work showed for the first time that taurine can promote neuroprotection in SH-SY5Y under oxidative stress caused by hydrocortisone. Cell viability was evaluated using crystal violet and the evaluation of cell morphology was performed by scanning electron microscopy (SEM). The viability of SH-SY5Y pre-treated with taurine and stressed with hydrocortisone was preserved, compared to the stressed only group, which was also morphologically observed. Therefore, taurine can represent a considerable therapeutic candidate in the prevention of neurodegenerative diseases, such as AD.
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    Photobiomodulation by LED 660 nm and Taurine against H2O2 oxidative stress in SH-SY5Y cells
    (Springer Nature Link) Rossato, Rafaella Carvalho; Salles, Geisa Rodrigues; Albuquerque, Amanda Lira; Porcionatto, Marimélia Aparecida; Granato, Alessandro Eustáquio Campos; Ulrich, Henning; Santos, Mariela Inês Batista dos; Soares, Cristina Pacheco
    Alzheimer's Disease (AD) is a progressive uncurable neurodegenerative pathology affecting millions worldwide. Photo- biomodulation and Taurine are promising alternatives for preventing and reducing the rapid progression of neurodegenera- tion, stimulating the reconstructing of neural tissue structures, especially improving mitochondrial activity, which is highly impaired in AD. In this study, the mitochondrial effects of Taurine combined with light emitting diode (LED) irradiation were evaluated on human neuroblastoma cells (SH-SY5Y), under oxidative stress condition by hydrogen peroxide (H2O2) exposure, a considerable modulator in AD. We evaluated LED irradiation at the wavelength of 660 nm and Taurine under different concentrations before and together with exposing SH-SY5Y cells to different concentrations of H2O2, assessing mitochondrial activity by the MTT colorimetric test and labeling live cells mitochondria by the fluorescent probe MitoTracker. Cell viability was also evaluated by the trypan blue exclusion assay, and cellular morphological structures were imaged by scanning electron microscopy (SEM). Neuroprotective effects were achieved by both LED irradiation and LED irradia- tion + Taurine when cells were exposed to them before H2O2-induced stress. Comparing both agents, LED irradiation at 660 nm is sufficient to improve mitochondrial activity, however, healthy mitochondrial morphology was only observed when cells were treated with Taurine together with LED irradiation, representing affordable candidates that act in synergy against oxidative stress, one of the main contributors to neurodegeneration.
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    Self-assembly and 3D Bioprinting of Neurospheres and Evaluation of Caffeine and Photobiomodulation Effects in an Alzheimer's Disease In Vitro Model
    (Springer Nature Link) Salles, Geisa Rodrigues; Granato, Alessandro Eustáquio Campos; Viero, Fernanda Tibolla; Soares, Cristina Pacheco; Ferreira, Sergio Teixeira; Porcionatto, Marimélia Aparecida; Ulrich, Henning
    Several in vitro models of Alzheimer’s disease (AD) rely on 2D cell culture, and, more recently, 3D cultures represented by free-floating neurospheres have been used as models for the disease. The advantage of 3D over 2D cell culture is that cell-extracellular matrix and cell-cell interactions can be assessed, better representing the molecular and cellular hallmarks of the disease. In the current study, we developed two complementary 3D neurosphere models using SH-SY5Y human neuroblastoma cells to investigate AD pathology and evaluate potential therapies. First, self-assembled neurospheres were exposed to hydrogen peroxide (H2O2) and amyloid-beta oligomers (AβOs), inducing AD-like features such as increased production of reactive oxygen species (ROS), amyloid aggregation, and apoptosis. Treatment with caffeine or photo- biomodulation (PBM) using LED irradiation significantly reduced Aβ1−42 accumulation, ROS generation, and decreased apoptosis markers. Second, 3D bioprinting of SH-SY5Y cells resulted in neurospheres with enhanced cellular organization and differentiation. These findings emphasize the advantages of 3D models for studying neurodegeneration and evaluating therapeutic strategies, bridging the gap between traditional 2D cultures and complex in vitro systems.
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    Evaluation of Photodynamic Therapy Using AuNPs@Ce6 in 3D Cultures of Triple-Negative Breast Cancer
    (MDPI) Ventura, Aveline; Gonçalves, Giulia Capizzani; Soares, Cristina Pacheco; Sant’anna, Luciana Barros; Marmo, Vitor Luca Moura; Sibelino, Sônia Khouri; Raniero, Leandro José
    Conventional cancer treatments have limited efficacy for aggressive subtypes such as triple-negative breast cancer (TNBC), which points to the importance of new therapeu- tic strategies. Functionalized nanoparticles in conjunction with photodynamic therapy (PDT) represent a promising alternative. Additionally, 3D cell culture emerges as a more effective model, as it better replicates the structural and functional characteristics of the tumor microenvironment. In this study, 3D microtumors of TNBC were cultivated and treated with PDT using gold nanoparticles functionalized with Chlorin e6 (AuNPs@Ce6). Cell viability was assessed using the MTT colorimetric assay, combined with histological analysis using hematoxylin-eosin staining. The MTT assay and histological evaluation of the 3D spheroids demonstrated that PDT with AuNPs@Ce6 effectively reduced cell viability and induced necrotic morphological changes, while maintaining biocompatibility with the non-irradiated control group. These findings reinforce the potential of this ap- proach for further investigation in TNBC models and underscore the value of 3D cultures as physiologically relevant and ethical alternatives to animal testing.
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    Ketoprofen Associated with Hyaluronic Acid Hydrogel for Temporomandibular Disorder Treatment: An In Vitro Study
    (MDPI) Miranda, Diego Garcia; Ramos, Lucas de Paula; Lopes, Nicole Fernanda dos Santos; Silva, Nicole Van Der Heijde Fernandes; Soares, Cristina Pacheco; Rodrigues, Flavia Pires; Morais, Vinicius de Paula; Sani-Taiariol, Thalita; Baldan, Mauricio Ribeiro; Vasconcellos, Luana Marotta Reis de; Borges, Alexandre Luiz Souto; Grosgogeat, Brigitte; Gritsch, Kerstin
    Temporomandibular disorders (TMD) are a public health problem that affects around 12% of the global population. The treatment is based on analgesics, non-steroidal anti-inflammatory, corticosteroids, anticonvulsants, or arthrocentesis associated with hyaluronic acid-based viscosup- plementation. However, the use of hyaluronic acid alone in viscosupplementation does not seem to be enough to regulate the intra-articular inflammatory process. So, we propose to develop and evaluate the physicochemical and biological properties in vitro of hyaluronic acid hydrogels (HA) associated with ketoprofen (KET) as a new therapeutic treatment for TMD. The hydrogels were synthesized with 3% HA and 0.125, 0.250, 0.500, or 1% KET. Physicochemical analyses of Attenu- ated Total reflectance-Fourier transform infrared spectroscopy (FTIR), Thermogravimetry (TGA), Rheology by Frequency, Amplitude sweeps, temperature ramp, and scanning electron microscopy (SEM) were performed with or without sterilization and cycled. Cytocompatibility and genotoxicity (micronucleus assay) were performed in mouse macrophages (RAW 264-7) for 24 h. Results: FTIR spectrum showed characteristic absorptions of HA and KET. In the TGA, two mass loss peaks were observed, the first representing the water evaporation at 30 and 100 ◦C, and the second peaks be- tween 200 and 300 ◦C, indicating the degradation of HA and KET. Rheology tests in the oscillatory regime classified the hydrogels as non-Newtonian fluids, time-dependent, and thixotropic. Mouse macrophages (RAW 264-7) presented viability of 83.6% for HA, 50.7% for KET, and 92.4%, 66.1%, 65.3%, and 87.7% for hydrogels, in addition to the absence of genotoxicity. Conclusions: Hyaluronic acid associated with ketoprofen shows satisfactory physicochemical and biological properties for use as viscosupplementation. As a limiting point of this study, further research is needed to evaluate the pharmacodynamic, toxicological, and pharmacokinetic characteristics of a complete organism.
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    Fluorescent Spider Silk: a Natural Phenomenon with Potential Applications
    (Springer Nature) Aranha, Guilherme Dias; Soares, Cristina Pacheco
    Spider silk is a well-known biomaterial that has been utilized throughout human history, primarily for medical pur- poses. It possesses a unique combination of capabilities not found in other materials, making it the subject of extensive research, which ranges from utilizing its mechanical properties to leveraging its biocompatibility within living organisms for medical treatments. Spiders also possess a unique combination of characteristics that help them survive, including the fluorescence of their hemolymph, carapace, and setae, which are suggested to aid in catching prey, communication, and camouflage. During tests of the spider silk’s capabilities and structure, fluorescence was discovered in the silk of one spe- cies and subsequently tested in other species. The discovery of this property led to the association of the spider’s natural fluorescence with its silk, suggesting that its role is linked to interactions between prey and predators. The spider attracts prey through its acute eyesight by mimicking the fluorescent patterns of flowers, making it difficult for prey to pinpoint the spider’s position on the web. This property could be utilized to develop new types of cell markers for medical applica- tions, incorporating the silk’s fluorescent components into cells, or to create novel textiles that exploit this characteristic, which lasts for long periods without losing its potency.